Joint Annual Meeting ISMRM-ESMRMB 2014 10-16 May 2014 Milan, Italy

TRADITIONAL POSTER SESSION ○ BODY

BODY (10:00-12:00)

2114-2127 Body: GI
2128-2176 Hepatobiliary/ Abdominal Imaging Techniques
2177-2214 Body: Kidney/GU
2215-2226 Body: Pelvis/Kidney
2227-2274 Body: Diabetes/DWI/IMRS
2275-2312 Pulmonary MRI/ GI
   

TRADITIONAL POSTER SESSION ○ BODY
Body: GI

 
Wednesday 14 May 2014
Traditional Poster Hall  10:00 - 12:00

2114.   Quantitative assessment of global small bowel motility in Chronic Intestinal Pseudo-Obstruction and controls: A Preliminary Study
Alex Menys1, Shamaila Butt2, Anton Emmanuel2, Natalia Zarate2, David Atkinson3, Andrew Plumb3, and Stuart A Taylor3
1Centre for Medical Imaging, UCL, London, Select, United Kingdom, 2GI Physiology Unit, UCLH, London, United Kingdom, 3Centre for Medical Imaging, UCL, London, United Kingdom

 
Quantified small bowel (SB) motility, assessed by analysis of dynamic MRI images, is an emerging tool for the investigation of dysmotility in a range of diseases. In this study, we report the initial findings with respect to global SB motility in a group of Chronic Intestinal pseudo-obstruction patients against healthy controls. We found a significant difference in basal small bowel motility between groups and, upon challenge with a pro-kinetic drug, increases in bowel motility in both groups. This study demonstrates the first clinical application of global SB motility analysis and encouraging results for the quantitative investigation of dysmotility in disease.

 
2115.   MRI colonic stress test for differentiating different subtypes of constipation
Gemma Chaddock1, Ching Lam2, Klara Garsed2, Caroline Hoad1, Carolyn Costigan1, Susan Pritchard1, Luca Marciani2, Robin Spiller2, and Penny Gowland1
1Physics & Astronomy, The University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, 2NIHR Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals Trust, Nottingham, Nottinghamshire, United Kingdom

 
We have assessed the colonic response of patients with chronic constipation (CC) to a laxative, using novel MRI methods. 40 patients took part in this one day open label study where serial MRI was used to assess whole gut transit time, small bowel water content, colonic volumes and colonic motility following oral ingestion of 1 L of a macrogol based laxative. We found quantifiable differences between the colonic responses of patients with different types of CC following ingestion of the laxative. This presents the opportunity to differentiate between patients with different forms of CC, allowing for more personalised treatment.

 
2116.   Preliminary investigations of colonic motility from Cine MRI; use of registration techniques for quantitative analysis
Caroline L. Hoad1, Valentin Hamy2, Klara Garsed3, Luca Marciani3, Robin C. Spiller3, Stuart A. Taylor2, David Atkinson2, Penny A. Gowland1, and Alex Menys2
1Sir Peter Mansfield Magnetic Resonance Centre, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, 2Centre for Medical Imaging, Division of Medicine, UCL, London, United Kingdom, 3Nottingham Digestive Disease Centre, Biomedical Research Unit in GI and Liver Diseases, University Hospitals NHS Trust and University of Nottingham, Nottingham, Nottinghamshire, United Kingdom

 
This study describes a preliminary investigation of the use of registration techniques to assess colonic motility. Cine MRI data from 10 healthy subjects pre- and 1 hour post an oral dose of a common laxative underwent dual registration to remove breathing effects and parameterise bowel motion. Significant area changes from 3 regions of interest across the AC were converted into a motility index and compared to observer scores of bowel wall contractions. The greatest agreement between the motility index and observer scores were seen for a change in area of greater than 5% of mean area.

 
2117.   Spatio-temporal analysis of antral peristaltic contractions using MRI
Eugene G. Kholmovski1,2, Layne Norlund2, Matthew Shonnard3, Hilary Riley3, and Grant W. Hennig3
1UCAIR, Department of Radiology, University of Utah, Salt Lake City, Utah, United States, 2CARMA Center, University Of Utah, Salt Lake City, Utah, United States, 3Department of Physiology & Cell Biology, University of Nevada, Reno, Nevada, United States

 
The use of MRI to study gastric motor function is limited and has mostly concentrated on quantifying volumes during gastric emptying [1]. Other important determinates of gastric motor function such as the velocity, frequency, and direction of antral peristaltic contractions have been more difficult to measure due to temporal undersampling and diaphragmatic distortion issues. We have developed MR image acquisition and data analysis methods to better ascertain how propagating antral contractions affect gastric emptying in health and disease.

 
2118.   Cine MRI Evaluation of Intestinal Motility in Neonates: A Feasibility Study
Jean A Tkach1, Mantosh S Rattan1, Charles L Dumoulin1, and Andrew P South2
1Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States, 2Neonatology and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States

 
Preterm and term neonates are at high risk of intestinal motility disorders. In older children and adults, cine MRI has proven useful in diagnosis and management of intestinal motility disorders. However, the standard technique includes breath holding and oral bowel preparation—procedures that cannot safely or practically be applied to neonates. In this study, cine MRI was obtained to assess intestinal motility in a cohort late preterm and term neonates. The qualitative and quantitative analysis of the motility data were consistent with that reported for adults, demonstrating cine MRI as a viable method to assess intestinal function in neonates.

 
2119.   Quantitative assessment of bowel motility in healthy individuals and patients with organic small bowel disease using MR cine -Initial Experiences
Zi Wang1, Hao Tang1, Xiaoyan Meng1, Jianjun Li1, and Daoyu Hu1
1Tongji Hospital,Tongji Medical College of Huazhong University of Science and Technology,Wuhan,China, Wuhan, Hubei, China

 
Function of small bowel motility is essential to sustain life, especially for patients suffering from small bowel diseases by whom those invasive examination such as intraluminal manometry may not be tolerated. In this study, dynamic MR series was used to evaluate the small bowel motility in healthy volunteers and patients with various kinds of organic small bowel diseases. Several types of abnormal peristalsis in patients group were differentiate from those in healthy volunteers.Clinician could make a more comprehensive view on the small bowel function in patients with organic small bowel diseases with the additional information provide by cine MR.

 
2120.   MR Endoscopy vs EUS: A Comparison
Richard Syms1, Chris Wadsworth2, Ian Young1, Marc Rea2, and Simon Taylor-Robinson2
1EEE Dept., Imperial College London, London, Middlesex, United Kingdom, 2St Mary's Hospital, Imperial College London, London, Middlesex, United Kingdom

 
Endoscopic ultrasound (EUS) is a well-established, safe modality for real-time imaging of the duodenum and nearby ductal systems. However, all echo-ranging imaging suffers from artifacts, the most significant being reverberation between impedance discontinuities. As a result, concentric artifacts dominate the near field. These artifacts cannot be suppressed without eliminating the fundamental contrast mechanism, unless a nonlinear contrast agent is used. As a result, EUS images are hard to interpret, and repeated scans are required. Although slower, internal MRI may therefore offer advantages. The aim of this paper is to compare the performance of a new MR-imaging duodenoscope with EUS.

 
2121.   Accuracy of non-contrast MRI for the evaluation of appendicitis
Iva Petkovska1, Bobby Kalb1, Shannon Urbina1, Matt Covington1, Puneet Sharma1, Hina Arif1, and Diego Martin1
1Medical Imaging, The University of Arizona, Tucson, Arizona, United States

 
To evaluate the sensitivity and specificity of MRI for the detection of acute appendicitis in patients less than or equal to 40 years old presenting to the emergency department (ED) with right lower quadrant pain (RLQP), primarily using only single shot partial Fourier spin echo-train T2 weighted images with and without fat-suppression, and without the use of either intravenous (IV) or oral contrast agents. We demonstrate that MRI is a highly accurate test for the evaluation of patients less than or equal to 40 yo with acute RLQP and a differential diagnosis of acute appendicitis utilizing a rapidly acquired imaging protocol that is relatively insensitive to breathing-related motion and performed without use of IV or oral contrast.

 
2122.   High Spatiotemporal Dynamic Contrast-Enhanced MRI of the Small Bowel in Active Crohn's Terminal Ileitis using Compressed Sensing, Parallel Imaging, and Golden-Angle Radial Sampling
Justin M Ream1, Ankur M Doshi1, Kai Tobias Block1, Sungheon Kim1, Ricardo Otazo1, Li Feng1, and Hersh Chandarana1
1Radiology, NYU Langone Medical Center, New York, NY, United States

 
GRASP imaging enables excellent spatial and temporal resolution for dynamic contrast enhanced MRI imaging of the small bowel.

 
2123.   Diffusion MRI in Crohn's Disease: Comparison with Fecal Calprotectin and MR-Enterography
Douglas Andrew Pendse1, Jesica Makanyanga1, Andrew Plumb1, David Atkinson1, and Stuart Taylor1
1Centre for Medical Imaging, University College London, London, London, United Kingdom

 
Therapeutic strategies in Crohn’s disease are dependent on both the degree of disease activity and the overall burden of disease in the gut. In this study we evaluated diffusion MRI (DWI) of the bowel in 69 adult patients with Crohns disease, using validated methods of MEGS score on MR-Enterography (MRE) and fecal Calprotectin (fC) as reference standards. Patients with abnormal DWI were shown to have significantly higher levels of fC and had higher MEGS score on conventional MRE. These data suggest that diffusion MRI is a clinically useful tool in the evaluation of Crohn’s activity.

 
2124.   Quantification of gastric secretion, mixing and emptying within single breath hold
Dian Liu1, Jelena Curcic1,2, Sebastian Kozerke1, and Andreas Steingoetter1,2
1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland, 2Division of Gastroenterology and Hepatology, University of Zurich, Zurich, Switzerland

 
A combined dual-flip angle, dual repetition T1B1 mapping scheme has been previously validated for in vivo quantification of gastric secretion and mixing. Practical limitation of this approach is the need for multiple breath hold cycles and its sensitivity to motion and flow. This study evaluates the combination of the novel rapid B1 mapping technique DREAM with slice profile correction and the dual-flip angle T1 mapping scheme for robust T1 quantification of gastric content during a single breath hold with improved co-registration of T1 and B1 maps.

 
2125.   Quantification of gastrointestinal liquid volumes following a 240 mL dose of water
Kathryn Murray1, Deanna Mudie2, Susan Pritchard1, Caroline Hoad1, Martin Garnett3, Gordon Amidon2, Penny Gowland1, Robin Spiller4, Gregory Amidon2, and Luca Marciani4
1Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, Nottingham, United Kingdom, 2College of Pharmacy, University of Michigan, MI, United States, 3School of Pharmacy, University of Nottingham, Nottingham, United Kingdom, 4Nottingham Digestive Diseases Centre and Nottingham Digestive Diseases Biomedical Research Unit, University of Nottingham, Nottingham, United Kingdom

 
Drug dissolution and absorption from solid oral dosage forms is highly dependent on the presence of liquid in the gut, but little is known about liquid volumes and distribution in vivo. This study detailes the time courses of the volume and number of liquid pockets in the upper gut of 12 healthy individuals following the ingestion of the industry standard 240 mL dose of water using MRI. These novel insights will help improve physiological relevance of modeling for prediction of bioperformance of low solubility oral solid dosage forms.

 
2126.   Faster MRI imaging of perianal fistulas through a limited sequence protocol based on high-resolution free-breathing post-contrast imaging, with comparison to standard care
Andreas M. Loening1, Pejman Ghanouni1, Joseph Y. Cheng2, Marcus T. Alley1, and Shreyas S. Vasanawala1
1Dept. of Radiology, Stanford University School of Medicine, Stanford, CA, United States, 2Electrical Engineering, Stanford University, Stanford, CA, United States

 
Standard MRI imaging of perianal fistulas utilizes multiple planes of T2 weighted sequences in addition to pre and post-contrast imaging. To decrease the length of time these studies require, we demonstrated that a fast protocol utilizing a single plane of T2 in combination with a high-resolution free-breathing post-contrast 3D SPGR sequence (with appropriate reformats derived during post-processing) was equivalent to a conventional protocol in the evaluation of perianal fistulas. This greatly reduces total scan time from 30-40 minutes to less than 15, and may in fact improve diagnostic accuracy.

 
2127.   Reproducibility of Diffusional Kurtosis Imaging for rectum in vivo
Xi sheng Cao1, Xiang Zheng1, Xiang yi Liu1, Chun miao Hu2, Wei Wei2, and Yun bin Chen3
1Department of Radiology, Provincial Clinical College of Fujian Medical University, Fuzhou, Fujian, China, 2Department of Radiology, Fujian Provincial Cancer Hospital, Fuzhou, Fujian, China, 3Department of Radiology, Provincial Clinical College of Fujian Medical University,Fujian Provincial Cancer Hospital, Fuzhou, Fujian, China

 
This paper is to assess the reproducibility of diffusional kurtosis imaging(DKI) for rectum in volunteers under normal breathing with background body signal suppression.

 
 

TRADITIONAL POSTER SESSION ○ BODY
Hepatobiliary/ Abdominal Imaging Techniques

 
Wednesday 14 May 2014
Traditional Poster Hall  10:00 - 12:00

2128.   Free-breathing quantification of liver proton density fat-fraction
Utaroh Motosugi1,2, Diego Hernando1, Peter Bannas1,3, James H. Holmes4, Kang Wang4, Ann Shimakawa5, Yuji Iwadate6, Valentina Taviani7, and Scott B. Reeder1,8
1Radiology, University of Wisconsin, Madison, WI, United States, 2Radiology, University of Yamanashi, Chuo-shi, Yamanashi, Japan, 3Radiology, University Hospital Hamburg-Eppendorf, Hamburg, Germany, 4Global MR Applications and Workflow, GE Healthcare, Madison, WI, United States, 5Global MR Applications and Workflow, GE Healthcare, Menlo Park, CA, United States, 6Global MR Applications and Workflow, GE Healthcare, Hino, Tokyo, Japan, 7Radiology, Stanford University, Stanford, CA, United States, 8Medical Physics, Biomedical Engineering and Medicine, University of Wisconsin, Madison, WI, United States

 
Proton density fat fraction (PDFF) is a promising biomarker for early detection and treatment monitoring of fatty liver disease. In order to obtain whole-liver coverage, current chemical shift-encoded MRI requires breath-holding for ~20s. In this study, we established two new free-breathing chemical shift-encoded MRI methods to acquire PDFF maps, and compared these methods to breath-hold MRI and MR spectroscopy. We found that the free-breathing methods (respiratory-gating with bellows or navigator echoes) were both equivalent to the breath-hold sequence for liver fat quantification. These novel sequences may be helpful for pediatric patients or patients who are unable to perform breath-holding.

 
2129.   Total liver fat quantification using a 3D respiratory self-gating technique
Carolina Arboleda Clavijo1, Daniel Aguirre-Reyes1, Cristián Tejos1, Loreto Muñoz2, Catalina Carvajal2, Pablo Irarrazaval1, Marcelo Andia3, and Sergio Uribe3
1Department of Electrical Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile, 2Chemistry and Bioprocesses Department, Pontificia Universidad Católica de Chile, Santiago, Chile, 3Department of Radiology, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile

 
We present a 3D 3-point Dixon liver fat imaging sequence with real-time respiratory self-gating to quantify fat fraction in the liver. The respiratory self-gating method monitors the breathing motion by acquiring a center k-space profile and adjusts the acquisition scheme to reacquire motion-corrupted data. To prove the applicability and precision of the technique, we performed experiments in a phantom consisting of several water-fat emulsions and in 13 volunteers. The results obtained show that the proposed method yields more precise fat fraction maps of the entire liver in a single free breathing scan than the current gold-standard method.

 
2130.   Temperature sensitivity of the triglyceride fat spectral model for Dixon based fat fraction quantification
Silke Hey1, Elwin de Weerdt1, Adri Duijndam1, Ivan Dimitrov2, and Liz Moore1
1Clinical Excellence, Philips Healthcare, Best, Netherlands, 2Philips Healthcare, Texas, United States

 
Methods based on the Dixon technique are increasingly used to quantify the triglyceride fat content of the liver. The employed pre-defined spectral model of triglyceride fat is very sensitive to modulations in spectral peak positions and amplitudes. Temperature and local susceptibility changes are known to induce shifts of the fat spectrum with respect to the water peak. In this study, we demonstrate the impact of temperature on the accuracy of measured fat fraction values which might be of high importance for a future standardization of Dixon based fat quantification methods.

 
2131.   Clinical Evaluation of Fast T2-Corrected MR Spectroscopy Compared to Multi-Point 3D Dixon for Hepatic Lipid and Iron Quantification
Puneet Sharma1, Xiaodong Zhong2, Jean-Philippe Galons3, Bobby Kalb3, Maria Altbach3, and Diego R Martin3
1Medical Imaging, University of Arizona, Tucson, Arizona, United States, 2MR R&D Collaborations, Siemens Healthcare, Atlanta, GA, United States, 3Medical Imaging, University of Arizona, Tucson, AZ, United States

 
This paper describes the clinical implementation of a fast, single-voxel spectroscopy technique for quantifying hepatic lipid fraction and evaluating iron content. The single breath hold technique was performed in consecutive patients, and analyzed retrospectively in comparison to a multi-point 3D Dixon lipid quantification method. The two methods show excellent agreement for quantifying lipid fraction, and estimating iron content.

 
2132.   Comparison between spectroscopy based fat quantification and two imaging based water-fat separation methods for the diagnosis of diffuse liver disease
Christian Kremser1, Benjamin Henninger1, Stefan Rauch1, Heinz Zoller2, Wolfgang Vogel2, Stephan Kannengiesser3, Xiaodong Zhong4, and Werner Jaschke1
1Dept. of Radiology, Innsbruck Medical University, Innsbruck, Austria, 2Dept. of Internal Medicine, Innsbruck Medical University, Innsbruck, Austria, 3MR Applications Development, Siemens AG Healthcare, Erlangen, Germany, 4MR R&D Collaborations, Siemens Medical Solutions, Atlanta, GA, United States

 
The evaluation of hepatic fat by MR techniques is of increasing interest for clinical routine. The purpose of our study was to compare fat quantification of the liver based on 1H spectroscopy and two different imaging based water-fat separation methods. All methods included correction for T2* bias. For clinical purposes a good correlation between the different fat quantification methods was found.

 
2133.   Accuracy of liver fat quantification by CT, MRI and US: a prospective comparison with Magnetic Resonance Spectroscopy (MRS)
Harald Kramer1,2, Mark A Kliewer2, Perry J Pickhardt2, Diego Hernando2, Gunag-Hong Chen2, and Scott B Reeder2,3
1Department of Radiology, Ludwig-Maximilians-University Munich, Munich, Germany, 2Department of Radiology, University of Wisconsin - Madison, Madison, Wisconsin, United States, 3Department of Medical Physics, University of Wisconsin - Madison, Madison, Wisconsin, United States

 
Accumulation of triglycerides in hepatocytes is the hallmark feature of non-alcoholic fatty liver disease and can lead to inflammation, fibrosis and cirrhosis. Since the accepted diagnostic standard (biopsy) is invasive and suffers from poor sampling variability, there is a need for a comprehensive, accurate and non-invasive quantitative biomarker. We evaluated a proton density fat-fraction chemical-shift based MRI technique, dual-energy CT and US shear-wave velocity in comparison to MR spectroscopy. PDFF-MRI shows excellent correlation with MRS whereas CT Hounsfield-Units and CT fat decomposition showed good and moderate correlation, respectively. US SW did not demonstrate any correlation with MRS.

 
2134.   Standard compared to optimized mDIXON liver fat fraction imaging
Jurgen H. Runge1, Bram F. Coolen1, Edmond Balidemaj2, Ulrich H. Beuers3, Aart J. Nederveen1, and Jaap Stoker1
1Radiology, Academic Medical Center, Amsterdam, Netherlands, 2Radiotherapy, Academic Medical Center, Amsterdam, Netherlands, 3Gastroenterology & Hepatology, Academic Medical Center, Amsterdam, Netherlands

 
Standard mDIXON fat-water imaging can be used to reconstruct quantitative fat fraction maps. However, a non-zero intercept of circa 4% is reported upon in recent literature. We optimized the mDIXON protocol by increasing the TR to reduce T1-weighting and by choosing more echoes with asymmetric TEs for a higher NSA. We investigated in phantoms and patients whether this optimized protocol increased accuracy in comparison to 1H-MRS. In phantoms, the non-zero intercept was resolved, but not in patients. Differences in T1 values of phantoms and tissue may explain why the issue remained for in vivo measurements.

 
2135.   Evaluation of Hepatic Fat Fraction Measured by MRI and Plasma Lipoprotein Levels in High-Fat Diet Fed Non-Human Primate
Ai Leng Liang1, Catherine D. G. Hines2, Li Chun Huang1, Shian-Jiun Shih1, Donald S. Williams2, Elaine Manigbas3, Brian Henry1, Jeffrey L. Evelhoch2, and Chih-Liang Chin1
1Translational Medicine Research Centre, MSD, Singapore, Singapore, 2Imaging, Merck & Co. Inc., West Point, Pennsylvania, United States, 3Imaging, Maccine Pte Ltd, Singapore, Singapore

 
We have established non-human primate (NHP) models of dyslipidemia by chronic feeding (9 mo.) two high-fat diets to male cynomolgus monkeys. Compared to normal diet fed NHPs, on average these animals (n=28) have doubled their total cholesterol, HDL- and LDL-cholesterol, but maintained triglyceride at baseline level. Additionally, their MRI-derived hepatic fat fraction (FF) increased from 2.4plus-or-minus sign0.6% to 7.7plus-or-minus sign4.5%. However, individual FFs do not correlate well with lipoprotein levels or ratios, probably due to small sample size and narrow data range. Our findings provide insights into lipid metabolism dysfunction in the dyslipidemic model and its potential utility for translational research.

 
2136.   Quantitative comparison of hepatic fat fraction in type 2 diabetes with triple-echo gradient echo MRI and proton MRS
Sunil K. Valaparla1,2, Goldie R. E. Boone1, Feng Gao1, Timothy Q. Duong1,2, and Geoffrey D. Clarke1,2
1Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States, 2Radiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States

 
Type 2 diabetes (T2DM) has been associated with excessive fat accumulation in the liver and definitive diagnosis using non-invasive fat estimation methods is essential for early treatment. We measured the liver fat fraction in T2DM subjects using triple-echo GRE MRI and compared with current gold standard 1H-MRS. Bland–Altman plots and regression analysis between methods exhibited excellent concordance and correlation. Triple-echo GRE MRI is fast, accurate, provides excellent concordance and correlation with MRS and can be used to replace time-consuming MRS for longitudinal and large cohort studies.

 
2137.   Quantification of triglyceride fatty acid composition in the fatty liver, subcutaneous and visceral adipose tissues with 3.0T MRI.
Benjamin Leporq1, Simon Auguste Lambert1, Helene Ratiney2, Gaspard D'Assignies1,3, Maxime Ronot1,3, Valerie Vilgrain1,3, Olivier Beuf2, and Bernard Van Beers1,3
1Center for research on inflammation, Université PARIS 7 ; INSERM U1149, Paris, France, 2CREATIS CNRS UMR 5220; INSERM U1044; INSA Lyon; UCBL Lyon 1, Universite de Lyon, Villeurbanne, France, 3Beaujon hospital; Department of radiology, Assistance Publique Hopitaux de Paris, Clichy, France

 
The aim of our study was to validate a 3.0T MRI method for quantifying triglyceride fatty acid (FA) composition. A 3D spoiled gradient multiple echoes sequence was used to acquire magnitude and phase images. Native phase images were corrected for wrap, zero- and first-order phase to rebuild the real part images. A model built upon a nine component fat 1H MR spectrum was used to derive three FA composition related parameters: the number of double bonds (ndb), the chain length (CL) and the number of methylene interrupted double bond (nmidb). Linear regressions showed a strong agreement between ndb, nmidb quantified with MRI on eight vegetables oils and the theoretical values calculated using oil composition. Measurements performed in the liver, in subcutaneous and visceral adipose tissues were consistent with previously published data.

 
2138.   Quantification of abdominal subcutaneous and visceral adipose tissue using a 3D CAIPIRINHA DIXON VIBE acquisition and automated segmentation
Venkatesh Mani1, Sarayu Ramachandran1, Sylvia Biso1, Joy Cambe1, and Zahi A. Fayad1
1Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States

 
Here, we present an optimized acquisition and image analysis methodology for automated segmentation of abdominal subcutaneous and visceral fat using a 3D CAIPIRINHA and DIXON based acquisition.

 
2139.   Abdominal imaging at 3T with fat suppressed PSIF using fat water separation
Chao Zou1, Qian Wan1, Xin Liu1, and Yiu-Cho Chung1
1Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China

 
PSIF is a good alternative to T2-TSE for its speed and good T2 contrast in abdominal imaging at 3T. We propose to apply fat/water decomposition to PSIF for robust fat suppression in abdominal imaging. In consideration of short TR in PSIF for higher SNR, three images with different TEs are acquired in an interleaved way and the TE increment was chosen as 0.57 ms. The phantom and volunteer shows the fat and water images are successfully derived from the PSIF images with three different TEs. T2 weighted PSIF water images are improved in diagnostic quality with robust fat suppression.

 
2140.   Phase Sensitive Dixon Inversion Recovery Imaging
Jinnan Wang1, Holger Eggers2, Chun Yuan3, and Peter Börnert2
1Philips Research North America, Seattle, WA, United States, 2Philips Research Europe, Hamburg, Hamburg, Germany, 3University of Washington, Seattle, WA, United States

 
Phase sensitive inversion recovery (PSIR) reconstruction is a commonly used technique for myocardial infarction detection. Myocardial fat, however, is a potential source of false positive detections. Direct inclusion of fat saturation in regular PSIR is not straightforward. In this work, a phase-sensitive reconstruction technique is combined with Dixon imaging to achieve phase-sensitive Dixon IR imaging. This technique can provide phase sensitive water and fat images without compromising scan efficiency. In vivo tests demonstrated its feasibility and advantages over regular PSIR in body imaging.

 
2141.   An Extended Fast Spin-Echo Triple-Echo Dixon Technique with Flexible Echo Separations
Jong Bum Son1, Ken-Pin Hwang1,2, John Madewell3, Ersin Bayram2, John Hazle1, and Jingfei Ma1
1Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States, 2Global MR Applications and Workflow, GE Healthcare, Houston, TX, United States, 3Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States

 
Fast spin echo triple-echo Dixon (FTED) acquires one in-phase (IP) and two out-of-phase (OP) images in a single acquisition without interleave. A potential drawback is that echo separation between the three readout gradients is fixed so that the minimum echo spacing of FTED as well as some scan parameters is not flexible. In this work, we propose an extended FTED pulse sequence in which the echo separation between the three readout gradients is mostly determined by the scan parameters. The proposed approach is capable of producing uniformly separated water and fat images with minimum echo spacing and adjustable scan parameters.

 
2142.   MR-based attenuation correction utilizing multi-echo flyback UTE IDEAL.
Sudhanya Chatterjee1, Kevin M Johnson2, Walter F Block2,3, and Alan B McMillan1
1Radiology, University of Wisconsin, Madison, Wisconsin, United States, 2Medical Physics, University of Wisconsin, Madison, Wisconsin, United States, 3Biomedical Engineering, University of Wisconsin, Madison, Wisconsin, United States

 
Quantitative PET imaging in PET/MR systems requires reliable methods for MR-based attenuation correction. While robust MR methods have been described to reliably distinguish fat and water within soft tissue, current MR methods provide limited sensitivity to lung tissue and bone, both of which exhibit substantially different photon absorption. Ultra short echo time imaging, which otherwise due to a very low SNR is a limiting factor for imaging techniques, has been used in this work to provide a motion-robust MR-based attenuation correction (MRAC) technique to segment MR images into water and fat components of soft tissue, bone, and lung.

 
2143.   Quantification of total adipose tissue in fetal guinea pigs subjected to suboptimal in utero conditions using water-fat MRI
Kevin J Sinclair1, Lanette J Friesen-Waldner1, Colin M McCurdy1, Curtis N Wiens2, Trevor P Wade1,3, Barbra de Vrijer4, Timothy RH Regnault4,5, and Charles A McKenzie1,3
1Department of Medical Biophysics, University of Western Ontario, London, Ontario, Canada, 2Department of Radiology, University of Wisconsin, Madison, Wisconsin, United States, 3Robarts Research Institute, University of Western Ontario, London, Ontario, Canada, 4Department of Obstetrics and Gynaecology, University of Western Ontario, London, Ontario, Canada, 5Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada

 
The metabolic syndrome is a cluster of morbidities that lead to an increased risk of developing cardiovascular disease. Studies suggest that the propensity to develop the metabolic syndrome can be programmed during fetal development. In this study, adipose tissue distributions in guinea pig fetuses were monitored using water-fat MRI. The fetuses were subjected to 3 different in utero conditions: over-nourishment, under-nourishment, and appropriate nourishment of the fetus. T1- and T2-weighted, as well as IDEAL water-fat images were acquired. Increased total adipose tissue was seen in the over-nourished case, while under-nourished fetuses had decreased total adipose tissue compared to normal.

 
2144.   Visual identification of brown adipose tissue in adult humans using Dixon MRI
Terence Jones1, Narendra Reddy2, Sarah Wayte3, Oludolapo Adesanya4, Thomas Barber5, and Charles Hutchinson1
1Medical School, University of Warwick, Coventry, West Midlands, United Kingdom, 2Metabolic Health, University Hospitals Coventry & Warwickshire, Coventry, CV2 2DX, United Kingdom, 3Medical Physics, University Hospitals Coventry & Warwickshire, Coventry, CV2 2DX, United Kingdom, 4Radiology, University Hospitals Coventry & Warwickshire, Coventry, West Midlands, United Kingdom, 5Health Sciences, University of Warwick, Coventry, West Midlands, United Kingdom

 
Ongoing interest in brown adipose tissue (BAT) has led to research in MRI as a potential tool for identifying and quantifying BAT, which is a necessary precursor to clinical trials evaluating pharmacological agents to stimulate BAT. We conducted a study in which areas of potential BAT were identified visually on Dixon MRI and compared with metabolically BAT on PET-CT using colocalization. Visual identification of BAT underestimates BAT volume, particularly when large levels of BAT are present. Conversely the degree of colocalization increases with increasing BAT volumes. This technique may be useful is evaluating future methods of prospective BAT identification.

 
2145.   Automated Volumetric Fat Quantification of Adipose Tissue in Mice
Colin M McCurdy1, Bryan T Addeman1, Curtis N Wiens2, Lanette J Friesen-Waldner1,3, Trevor P Wade1,3, Jacqueline K Harris1, Abraam S Soliman4, Kevin J Sinclair1, and Charles A McKenzie1,4
1Medical Biophysics, The University of Western Ontario, London, Ontario, Canada, 2Radiology, The University of Wisconsin, Madison, Wisconsin, United States, 3Robarts Research Institute, London, Ontario, Canada, 4Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada

 
Excess Intra-Abdominal Adipose Tissue (IAAT) is predictive of the onset of type-2 diabetes and cardiovascular disease. Evaluating adipose tissue volume in mouse models of disease would allow non-invasive investigation of diet or treatment induced changes in fat distribution. Here we demonstrate the adaptation of an automated method for quantification of human adipose tissue for use in mouse MRI. This method was validated by comparison to manual segmentations of normal and obese mice. Bland-Altman analysis showed differences between manual and automated analysis of (6.7 ± 4.7) mm^3 for subcutaneous adipose tissue and (5.2 ± 3.6) mm^3 for IAAT.

 
2146.   T2* from fat-water MRI is sensitive to local adipose tissue inflammatory changes in a diet-induced obesity mouse model at 15T
Henry H. Ong1,2, Corey D. Webb3, Marnie L. Gruen3, Alyssa H. Hasty3, John C. Gore1,2, and E. Brian Welch1,2
1Vanderbilt University Institute of Imaging Sciences, Nashville, TN, United States, 2Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States,3Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, United States

 
In obesity, fat-water MRI (FWMRI) methods provide valuable information on adipose tissue (AT) distribution. AT is known to undergo complex metabolic and endocrine changes in association with chronic inflammation. We investigated the potential for quantitative FWMRI to be sensitive to AT inflammatory changes in an established diet-induced obesity mouse model. We examined T2* estimates from the fat-water separation algorithm and observed an increasing shift toward higher T2* values in perirenal AT with increasing obesity as compared with normal weight mice. Quantitative FWMRI T2* measurement shows potential for longitudinal non-invasive assessment of AT dysfunction in obesity.

 
2147.   Liver iron content measurement using quantitative susceptibility mapping
Alexey Dimov1,2, Pascal Spincemaille3, Carlo Salustri3, Tian Liu4, Bo Xu1,2, and Yi Wang1,2
1Biomedical Engineering, Cornell University, Ithaca, NY, United States, 2Radiology, Weill Cornell Medical College, New York, NY, United States, 3Radiology, Weill Cornell Medical College, NY, United States, 4MedimageMetric LLC, NY, United States

 
The quantification of iron content is traditionally performed by R2* mapping, which is sensitive to imaging parameters and affected by large field inhomogeneity such as near the liver-lung interface. In this abstract, we propose the use of a breath-hold 3D spiral multi-echo flow compensated sequence combined with an adaptive fat-water separation method to obtain liver iron content based on magnetic susceptibility.

 
2148.   Comparison of serum liver function tests and liver R2* measurements before and after gadoxetic acid
Diego Hernando1, Shane A. Wells2, Karl K. Vigen1, and Scott B. Reeder1,3
1Radiology, University of Wisconsin-Madison, Madison, WI, United States, 2Radiology, University of Virginia, Charlottesville, VA, United States, 3Medicine, University of Wisconsin-Madison, Madison, WI, United States

 
Previous studies have shown that R2* increases in normal liver after contrast administration. In this work, we investigated the relationship between patients’ clinical data, including body mass index (BMI) and blood analysis results, and R2* measurement, performed before and after administration of gadoxetic acid. A lack of increase of R2* after contrast administration was correlated with elevated values of both total bilirubin and MELD scores, which are measures of liver function and severity of chronic liver disease.

 
2149.   The value of severe liver iron overload to predict cardiac iron level
Xiaodong Chen1,2, Hui Zhang3, Xihai Zhao3, Huailing Zhang4, Biling Liang5, and Hua Guo3
1Sun Yat-Sen Memorial Hospital, Guangzhou, Guangdong, China, 2Guangdong Medical College, Guangdong, China, 3Biomedical Engineering&Center for Biomedical Imaging research,School of Medicine,Tsinghua University, Beijing, China, 4School of Information Engineering, Guangdong Medical College, Guangdong, China, 5Sun Yat-Sen Memorial Hospital, Guangdong, China

 
Cardiac failure is the main causes of death in patients with thalassemia major 1,2. But its diagnosis is often hysteretic in clinical practice, which probably in consequence of the unpredictability of cardiac iron deposition as well as the lag of appearance of symptoms, Thus, it is vital to monitor the cardiac iron level even in asymptomatic patients. Hepatic iron concentration has been widely used as the indicator of this disease. However, it lacks extensive investigation about the relationship between hepatic iron overload and myocardium iron overload, especially when the liver has severe deposition.

 
2150.   
MR Tagging based cardiac-induced liver deformation analysis in murine model of non-alcoholic fatty liver disease
Anna Osiak1, Krzysztof Jasinski1, Pawel T. Jochym2, Edyta Maslak3, and Tomasz Skorka1
1Department of Magnetic Resonance Imaging, Institute of Nuclear Physics Polish Academy of Sciences, Kraków, Poland, 2Department of Materials Research by Computers, Institute of Nuclear Physics Polish Academy of Sciences, Kraków, Poland, 3Department of Endothelium Experimental Pharmacology, Jagiellonian Center for Experimental Therapeutics (JCET), Kraków, Poland

 
The objective was to assess cardiac-induced liver deformation in murine model of non-alcoholic fatty liver disease (NAFLD) using MR Tagging. Control and NAFLD mice were examined and liver tissue displacements Disp, E1 and E2 principal strains were computed within 7 regions and normalized to maximum heart declination. In NAFLD the tissue compression increased, maximum Disp and E1 were preserved, but the deformation were propagated deeper in the organ compared to controls, what may reflect increased fat deposition at non-fibrotic stage of pathology. Good consistency of the results suggests the routine may be helpful for evaluation of fat deposition degree.

 
2151.   Hepatic MR Elastography by Using Optimized Flexible Drivers
Jun Chen1, Kevin Glaser1, Meng Yin1, Jayant Talwalkar1, Phillip Rossman1, Sudhakar Venkatesh1, and Richard Ehman1
1Mayo Clinic, Rochester, MN, United States

 
Hepatic MR Elastography (MRE) is an accurate noninvasive method for detecting liver fibrosis. Conventional drivers for hepatic MRE are usually rigid, but human bodies are soft and contoured. Therefore, the mechanical coupling between rigid drivers and human body is often not optimal, resulting in potential issues such as wave interferences in the liver. Previous developed hepatic flexible driver was optimized in this study for higher efficiency. Patients with a large range of liver fibrosis stage underwent MRE with both the flexible and rigid drivers. The mean difference was 0.11kPa, indicating that both drivers are equivalent for measuring liver stiffness.

 
2152.   Comparing 2D and 3D Magnetic Resonance Elastography Techniques in a Clinical Setting: Initial Experiences
Mikael F. Forsgren1,2, Bengt Norén3,4, Johan Kihlberg2,3, Olof Dahlqvist Leinhard2,3, Stergios Kechagias5, and Peter Lundberg3,6
1Wolfram MathCore AB, Linköping, Sweden, and Center for Medical Image Science and Visualization(CMIV), Linköping University, Linköping, Sweden, 2Dept. of Medical and Health Sciences, Linköping University, Dept. of Radiation Physics, UHL County Council of Östergötland, Linköping, Sweden, 3Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden, 4Dept. of Medical and Health Sciences, Linköping University, Linköping, Sweden, 5Dept. of Medical and Health Sciences, Linköping University, Dept. of Gastroenterology and Hepatology, UHL County Council of Östergötland, Linköping, Sweden, 6Dept. of Medical and Health Sciences, Linköping University, Depts. of Radiation Physics and Radiology, UHL County Council of Östergötland, Linköping, Sweden

 
Fibrosis may be reversible in humans, thus there is a great need for the introduction of noninvasive methods in order to monitor fibrosis development. MRE seems to be very promising towards this end. However, we need to verify that different techniques provide comparable results for a wide spread clinic introduction. We have compared 2D and 3D MRE techniques using two different transducer technologies. We examined 7 patients in a single day with a very short time delay (10 min). Our results show that it is possible to obtain comparable estimate of stiffness/elasticity in the liver using different techniques.

 
2153.   The repeatability of the Magnetic Resonance Elastography derived stiffness value in the liver
Alexander D Cohen1, Mark D Hohenwalter2, and Kathleen M Schmainda1,2
1Biophysics, Medical College of Wisconsin, Milwaukee, WI, United States, 2Radiology, Medical College of Wisconsin, Milwaukee, WI, United States

 
Magnetic Resonance Elastography (MRE) has gained prominence for its ability to stage liver fibrosis. MRE measures the propagation of acoustic shear waves, generated by a passive driver, through liver tissue. MRE gives estimates of liver stiffness, which have directly correlated with fibrosis grade in preliminary studies. MRE repeatability was assessed in a cohort of normal volunteers and cirrhotic patients imaged twice in one scanning session. Repeatability was excellent for both the volunteers and cirrhotic patients, and indicate changes must be larger than ~10% to be significant for longitudinal studies and ~10-30% to be significant for between group studies.

 
2154.   Accuracy of Hepatic Fibrosis Staging Using T2-WI and Texture Analysis
Karen Buch1, Baojun Li2, Hei Shun Yu2, Brian Tischler3, Naznin Daginawala3, and Stephan Anderson4
1Radiology, Boston University Medical Center, Boston, MA, United States, 2Boston University Medical Center, Boston, United States, 3Boston University Medical Center, MA, United States, 4Radiology, Boston University Medical Center, Boston, United States

 
The purpose of this study was to evaluate the accuracy of texture analysis applied to T2-weighted images to assess hepatic fibrosis using a linear discriminant analysis. A total of 27 patients with varying grades of biopsy-proven hepatic fibrosis were analyzed with a sensitivity of up to 90% and specificity of 88% for GLCM entropy versus energy texture parameters. The development of accurate, non-invasive methods for the assessment and staging of liver fibrosis is crucial given a growing global impact of chronic liver disease and fibrosis. The application of texture analysis tools using T2-weighted images, possibly as part of a multi-parametric approach, affords the possibility of developing an accurate, noninvasive assessment of hepatic fibrosis.

 
2155.   Distinction between non-advanced and advanced liver fibrosis: Comparison between MR DCE imaging and T2-corrected IVIM at 3.0T.
Benjamin LEPORQ1, Frank Pilleul2,3, Jerome Dumortier4, Olivier Guillaud4, Thibaud Lefort5, Pierre-Jean Valette5, and Olivier Beuf2
1Center for research on inflammation, Université PARIS 7 ; INSERM U1149, Paris, France, 2CREATIS CNRS UMR 5220; INSERM U1044; INSA Lyon; UCBL Lyon 1, Universite de Lyon, Villeurbanne, France, 3Centre de lutte contre le cancer, Centre Léon Berard, Lyon, France, 4CHU Edouard Herriot; Department of hepatology, Hospices Civils de Lyon, Lyon, France, 5CHU Edouard Herriot; Department of gastro-intestinal imaging, Hospices Civils de Lyon, Lyon, France

 
Our objective was to evaluate T2-corrected IVIM and perfusion imaging using a MR-DCE technique for the distinction between non-advanced and advanced fibrosis in patients with chronic liver diseases. The link between perfusion-related diffusion given by IVIM and quantitative perfusion parameters given by MR-DCE imaging was investigated. Results indicated that the combination of IVIM and MR-DCE imaging do not bring additional information for fibrosis assessment in a large spectra of etiologies. Indeed, perfusion parameters given by MR-DCE imaging alone are relevant to evaluate fibrosis severity. Strong correlation between portal perfusion and perfusion related diffusion coefficient illustrated that IVIM reflects the hemodynamic changes occurring in fibrous damage. Pure molecular diffusion coefficient was affected by the deposition of extracellular matrix components and by fat vesicle suggesting that fat overload can constitute a confounding factor in fibrosis assessment with IVIM. Nevertheless, if fat overload is addressed, IVIM could be a useful injection-free method to distinguish between non-advanced and advanced fibrosis.

 
2156.   Imaging Liver Fibrosis and Response to Rapamycin Therapy
Christian T. Farrar1, Bryan C. Fuchs2, Helen Day1, Nicholas Rotile1, Danielle DePeralta2, Arun Subramaniam3, Kenneth K. Tanabe2, and Peter Caravan1
1Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States, 2Surgical Oncology Division, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States, 3Sanofi-Aventis, Bridgewater, NJ, United States

 
There is a critical unmet medical need for non-invasive methods for quantifying liver fibrosis to facilitate early diagnosis, monitor disease progression, and assess response to therapies. Here we demonstrate the use of the collagen-targeted contrast agent EP-3533 to monitor progression of liver fibrosis in a bile duct ligation rat model of liver fibrosis and to assess response to rapamycin therapy.

 
2157.   Accuracy of Texture Analysis to Detect Hepatic Fibrosis on T1 Weighted Contrast Enhanced MR
Hei Shun Yu1, Baojun Li2, Karen Buch2, Naznin Daginawala2, Brian Tischler2, and Stephan Anderson2
1Boston University Medical Center, Boston, MA, United States, 2Boston University Medical Center, MA, United States

 
The purpose of this study was to diagnose and stage hepatic fibrosis by performing a texture analysis on post-gadolinium T1 weighted images of the liver parenchyma in the portal venous and equilibrium phases. A MATLAB-based texture analysis program was employed to extract 42 texture features for thirty patients. These texture parameters were analyzed using a linear discriminant analysis to calculate sensitivities and specificities. Findings of this study demosntrate specificities of 72% and 82% discriminating lower from higher grades of hepatic fibrosis on equilibrium and venous phases. The ability to non-invasively assess and quantify the severity of hepatic fibrosis is of diagnostic clinical importance and could potentially minimize invasive biopsy techniques to assess severity of fibrosis.

 
2158.   T1lower case Greek rho relaxation of the liver; a new biochemical marker of liver function in patients with diffuse liver disease
Yukihisa Takayama1, Akihiro Nishie2, Yoshiki Asayama2, Yasuhiro Ushijima2, Nobuhiro Fujita2, Koichiro Morita2, Takashi Yoshiura2, Tomoyuki Okuaki3, Makoto Obara3, and Hiroshi Honda2
1Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan, 2Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan, 3Philips Electronics Japan, Tokyo, Japan

 
We investigated the clinical utility of T1lower case Greek rho mapping for the assessment of liver function in patients with chronic liver diseases (CLD) by comparing T1lower case Greek rho mapping with patientsf blood serum parameters. T1lower case Greek rho value of the liver parenchyma showed significant correlations with serum albumin level, serum total and direct bilirubin levels, and ICG-R15 (the retention rate of indocyanine green 15 min after administration). Especially, T1lower case Greek rho values of the liver parenchyma were prolonged with increasing ICG-R15 which indicates a worsening of liver function. T1lower case Greek rho relaxation may server as a new biochemical marker of liver function.

 
2159.   A study on T1lower case Greek rho mapping of Healthy and Fibrotic Human Liver
Anup Singh1, Damodar Reddy1, Mohammad Haris1,2, Kejia Cai1,3, Rebecca Wells4, Emma E. Furth5, K. Rajender Reddy4, Hari Hariharan1, and Ravinder Reddy1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Research Branch, Sidra Medical and Research Center, Doha, Qatar, 3Radiology, University of Illinois at Chicago, Chicago, IL, United States, 4Department of Medicine, University of Pennsylvania, Philadelpha, PA, United States, 5Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelpha, PA, United States

 
Objective of current study was to evaluate T1ñ changes in fibrotic human liver. In the current study, T1ñ mapping and analysis of healthy (n=10) and fibrotic (n=10) livers of human subjects on 1.5T clinical scanner were carried out. T1ñ values were significantly higher in fibrotic livers compared to healthy livers. In addition, T1ñ maps of some of the fibrotic liver were more heterogeneous compared to healthy liver. Histogram analysis of T1ñ values was also performed. Results from this preliminary study show the potential of staging liver fibrosis based upon increased T1ñ values in combination with width of histogram and mode values.

 
2160.   Volumetric T1 Mapping of liver parenchyma at 3 T: Diagnosing Liver Cirrhosis
Niklas Verloh1, Claudia Fellner1, Michael Haimerl1, Mona Schlabeck1, Miriam Rabea Kukach2, Marcel D. Nickel2, Christian Stroszczynski1, and Philipp Wiggermann1
1Department of Radiology, University Hospital Regensburg, Regensburg, Germany, 2MR Applications Development, Siemens AG, Healthcare Sector, Erlangen, Germany

 
The purpose of the study was to assess the ability of volumetric T1 mapping of Gd-EOB-DTPA-enhanced MRI to detect liver cirrhosis. Mean T1 relaxation time of the whole liver parenchyma was used to calculate the reduction rate between plain and enhanced T1 relaxation time. Patients with and without liver cirrhosis were analyzed regarding their reduction rate. The reduction rate of the whole liver was significantly (p ≤ 0.001) lower in patients with liver cirrhosis (35% ± 8%) compared to patients with normal liver function (58% ± 6%). The evaluation of changes in T1 mapping of liver parenchyma in Gd-EOB-DTPA-enhanced images may serve as a useful new, non-invasive technique to quantify liver cirrhosis

 
2161.   T1 mapping on gadoxetate disodium enhanced MRI in patients with primary sclerosing cholangitis (PSC)
Kristina Imeen Ringe1, Marcel Gutberlet1, Frank Wacker1, and Hans-Jürgen Raatschen1
1Department of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany

 
In our prospective study we sought to assess the value of T1-mapping of the liver on gadoxetate-disodium enhanced MRI in patients with PSC. In 40 patients T1-mapping of the whole liver was performed using a 3D GRE-sequence with different flip angles before and after contrast injection. T1 relaxation times in all liver segments were assessed and correlated with liver function tests. T1 relaxation times after contrast injection significantly decreased and correlated with bilirubin, cholinesterase and GOT. Our findings may be useful for dynamic evaluation and follow-up of patients with PSC, as well as for guidance of biopsies.

 
2162.   Patch-Based Reconstruction Of Undersampled Images (PROUD) for Sub-second Frame Rate 4D Contrast Enhanced Liver Imaging
Mitchell Anthony Cooper1,2, Pascal Spincemaille2, Bo Xu1,2, Thanh D Nguyen2, Martin R. Prince2, Michael Elad3, and Yi Wang1,2
1Biomedical Engineering, Cornell University, Ithaca, New York, United States, 2Radiology, Weill Cornell Medical College, New York, New York, United States, 3Computer Science, Technion - Israel Institute of Technology, Haifa, Israel

 
High temporal & spatial resolution 4D imaging with large volume coverage is needed to accurately capture organ perfusion. Typically, parallel-imaging reconstruction is done to achieve high frame rate and large volume coverage and results in a loss of signal to noise ratio compared to Nyquist sampling. Furthermore, residual under-sampling artifacts are temporally varying and complicate the quantitative analysis of contrast enhancement curves needed for pharmacokinetic modeling. Here, we propose a method, Patch based Reconstruction Of Undersampled Data or PROUD, that will both improve noise characteristics as well as minimize temporally-varying residual artifacts.

 
2163.   Pharmakokinetic modeling and quantification of the liver function using DCE-MRI with contrast agent Gd-EOB-DTPA
Patrick Zylka1, Timm Denecke2, Dominik Geisel2, and Lutz Lüdemann1
1Klinik und Poliklinik für Strahlentherapie, Universitätsklinikum Essen, Essen, NRW, Germany, 2Klinik für Radiologie, Charité Universitätsmedizin Berlin, Berlin, NRW, Germany

 
We investigate the possibility to establish a mathematical model which is able to describe liver parameters noninvasive and space-resolved by magnetic resonance imaging (DCE-MRI). We use Gd-EOB-DTPA as contrast agent which is metabolized by healthy hepatocytes whereas the metabolism of damaged cells is strongly suppressed. Determing the rate of metabolism we can compare liver regions to quantify the degree of function loss. After converting voxel signal to relaxation rate (which is proportional to the contrast agent concentration), the data of a chosen liver area is handed to a computer program. The algorithm is based on a two-compartment-model and returns the parameters "overall flow", “mean transit time”, "hepatic input / extraction rate" as well as the compartment volumes.

 
2164.   Flexible Temporal Reconstruction of Continuously Acquired Dynamic Contrast Enhanced Acquisition for Simultaneous Perfusion and Morphologic Imaging of the Abdomen
Hersh Chandarana1, Benjamin Abiri1, Byron Gaing1, Justin Ream1, Andrew Rosenkrantz1, Mary Bruno1, Henry Rusinek1, and Kai Tobias Block1
1Radiology, NYU Langone Medical Center, New York, NY, United States

 
Perfusion weighted imaging (PWI) is not incorporated into routinely abdominal imaging due to the need for additional contrast injection and acquisition time. We have developed a novel acquisition and reconstruction method called GRASP (GRASP: Golden-angle RAdial Sparse Parallel) whereby data is acquired continuously in free-breathing and retrospectively reconstructed with flexible temporal resolution. In this study we have shown that high temporal GRASP reconstruction can be used for PWI to accurately measure kidney function (MR-GFR) as compared with the Cartesian scheme. Furthermore images reconstructed with different temporal resolution from a single acquisition can be used for morphologic evaluation.

 
2165.   Gadoxetate contrast kinetics are altered in rat liver by a peptide deformylase inhibitor known to induce phospholipidosis
Stephen Clark Lenhard1, Mary Rambo2, Ciara Rodgers2, Mark Burgert2, Lindsey Webster3, Richard Peterson3, Richard Miller3, and Beat Jucker2
1GlaxoSmithKline, King of Prussia, PA, United States, 2GlaxoSmithKline, PA, United States, 3GlaxoSmithKline, NC, United States

 
Phospholipidosis (PLD) is a generalized condition in humans and animals characterized by an intracellular accumulation of phospholipids. Using a clinically available liver specific MRI contrast agent (Eovist™;Gadoxetate), hepatobiliary Dynamic Contrast Enhanced MRI (DCE-MRI) was performed to determine if Gadoxetate kinetic changes could be detected with a compound known to induce PLD. Gadoxetate DCE MRI of liver function may be a useful pre-clinical technique to assess hepatic functional consequences of PLD in vivo to support drug development decisions for compounds found to induce PLD.

 
2167.   Diagnosis of Liver Hemangioma: Novel Application of Gd-EOB-DTPA-Enhanced MRI in conjunction with Flow-Sensitive Black Blood Technique
Jun Isogai1, Takashi Yamada2, Hideo Hatakeyama2, Tomoko Miyata3, Kenji Yodo3, Mitsue Miyazaki4, and Jun Kaneko2
1Asahi General Hospital, Asahi, Chiba, Japan, 2Hasuda Hospital, Saitama, Japan, 3Toshiba Medical Systems Corp., Saitama, Japan, 4Toshiba Medical Research Institute USA, Inc., IL, United States

 
Gadlinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) is an alternative hepatobiliary contrast agent that allows combination of dynamic imaging and hepatocyte-specific imaging in a single examination. Several reports have shown that liver tumors can be reliably detected at a high rate using hepatobiliary contrast agents. However, liver hemangiomas are often difficult to distinguish from malignant tumors such as liver metastases and hepatocellular carcinoma. The purpose of this study is to evaluate the usefulness of FSBB technique with Gd-EOB-DTPA in the diagnosis of liver hemangioma.

 
2168.   Quantitative perfusion of hepatocellular carcinoma before and after Y-90 radioembolization using a MR angiographic technique with multi-echo and radial k-space sampling
N. Chatterjee1,2, R. J. Lewandowski1, E. Semaan1, R. Salem1, R. Ryu1, K. Sato1, F. Miller1, J. C. Carr1, T. J. Carroll1,2, and J. D. Collins1
1Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States, 2Department of Biomedical Engineering, Northwestern University, Chicago, IL, United States

 
Assessing early HCC treatment response following Y-90 RAE is often challenging using conventional CT and MR techniques due to lesion enlargement and heterogeneous peripheral contrast enhancement. Quantitative assessment of the necrotic core (EASL criteria) has shown promise for predicting response to therapy. We present early data evaluating quantitative target lesion perfusion using a radially sampled CE-MRA sequence employing echo-sharing to achieve a 64-fold temporal acceleration and an effective temporal resolution of 45msec. Preliminary results demonstrate that hyperemic effects of regional liver radiation injury raises the absolute target lesion perfusion, requiring normalization to either remote or adjacent liver parenchymal perfusion.

 
2169.   Extracting arterial to portal hepatic flow ratio using high frame rate Gd MRI
Lorne W Hofstetter1, Mitchell A Cooper1, Silvina P Dutruel1, Mahajabin Rahman1, Shan Hu1, Nandadeepa Thimmappa1, Pascal Spincemaille1, Yi Wang1, and Martin R Prince1
1Radiology, Weill Cornell Medical College, New York, New York, United States

 
On time-resolved contrast enhanced MRI, a cirrhotic liver tends to enhance less and more slowly than the normal liver. In addition, it is well known that the ratio of arterial to portal blood supply for the liver increases in cirrhosis. In previous approaches, a separate 2D contrast enhanced exam was necessary to sample the liver enhancement curve with high temporal resolution, complicating the integration of this method into clinical practice. We hypothesize that these differences in liver perfusion between normal and cirrhotic liver can be detected using a high frame rate 3D contrast enhanced MRI of the liver obtained with the TRACER method.

 
2170.   Volume interpolated breathhold examination (VIBE) and software-assisted MR-guided RFA for the treatment of malignant liver tumors: Initial clinical results
Diethard Schmidt1,2, Andreas Weihusen3, Stephan Clasen2, Hans Jörg Rempp2, Christina Schraml2, Andreas Boss1, Fritz Schick4, Claus D Claussen2, and Philippe L Pereira5
1Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Kanton Zurich, Switzerland, 2Diagnostic and Interventional Radiology, University Hospital Tubingen, Tubingen, Baden-Württemberg, Germany, 3Computing imaging, FraunhoferMevis, Bremen, Germany, 4Section for experimental radiology, University Hospital Tubingen, Tubingen, Baden-Württemberg, Germany, 5Radiology, SLK-Kliniken, Heilbronn, Baden-Württemberg, Germany

 
Evaluation of software-assistance and VIBE to optimize MR guided RFA of malignant livertumors

 
2171.   T2-weighted 4D-MRI with combined phase and amplitude sorting
Yilin Liu1, Zheng Chang2, Brian Czito2, Mustafa Bashir2, Fang-Fang Yin2, and Jing Cai2
1Medical Physics, Duke University, Durham, NC, United States, 2Duke University, NC, United States

 
In this study, we demonstrated the feasibility of a novel retrospective T2-W 4D-MRI phase and amplitude hybrid sorting method based on HASTE/SSFSE sequence. A result-driven sorting strategy was induced in this technique. The T2-W 4D-MRI technique can be applied on liver, pancreas and many other abdominal regions to exhibit the motion of tumors or critical organs. To validate our technique, 4D-MRI acquisition and reconstruction were tested on a 4D Digital Extended Cardiac-Torso (XCAT) human phantom. 5 healthy volunteers were involved in a human study for this technique. Future evaluation on patients is desired.

 
2172.   Pulsatility artifact suppression using slice-selective motion-sensitized driven-equilibrium (MSDE): A feasibility study
Maggie M Fung1, Lloyd Estkowski2, and Ersin Bayram3
1Global MR Applications and Workflow, GE Healthcare, Jersey City, NJ, United States, 2Global MR Applications and Workflow, GE Healthcare, Menlo Park, CA, United States,3Global MR Applications and Workflow, GE Healthcare, Houston, TX, United States

 
In body & breast imaging, pulsatility artifacts are often observed due to high aortic flow or cardiac motion. We proposed a slice-selective Motion-sensitized driven-equilibrium (MSDE) technique that enables selective suppression of unwanted flow signal in user specific planes, ideally outside of the main region of interest (ROI). In this study, we have shown the feasibility that slice selective MSDE can be applied outside the main ROI to suppress upstream flow, and the SNR at the main ROI would not be affected while achieving blood suppression effect.

 
2173.   A navigated bSSFP sequence for volumetric liver respiratory motion measurement
Chuan Huang1, Yoann Petibon1, Timothy G Reese2, Jinsong Ouyang1, and Georges El Fakhri1
1Center for Advanced Medical Imaging Sciences, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States, 2Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States

 
The respiratory motion of the liver is desired in many clinical applications including respiratory motion compensated image acquisition/reconstruction and image-guided interventions in the liver. Recent advancement in simultaneous MR-PET acquisition enables the possibility to accurately perform MR-assisted liver PET respiratory motion correction using liver motion measured by MR. So far, T1-weighted MRI and tagged MRI have been investigated in the MR-assisted liver motion correction. However, neither T1w MRI nor tagged MRI is optimal for liver respiratory motion measurement in human due to lack of contrast in T1w images in the liver and fading away of tags (T1 of liver is approximately 700ms while respiration cycle is about 5s). In this work, we propose a strategy to obtain the volumetric liver motion field using a navigated slice-by-slice balanced steady-state free precession (Nav-bSSFP) sequence.

 
2174.   Flip angle modulation in single shot fast spin echo imaging greatly increases speed with little change in diagnostic image quality
Andreas M. Loening1, Manojkumar Saranathan1, Nichanan Ruangwattanapaisarn2, Daniel V. Litwiller3, Ann Shimakawa3, and Shreyas S. Vasanawala1
1Dept. of Radiology, Stanford University School of Medicine, Stanford, CA, United States, 2Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand,3GE Healthcare Global MR Applications and Workflow, Rochester, MN, Menlo Park, CA, United States

 
Single shot fast spin echo acquisition speed is limited by specific absorption rate (SAR). Instead of using a constant low flip angle to reduce SAR, we modulated the refocusing flip angle over the course of the echo train and achieved an at least doubling of imaging speed (2-fold reduction in TR) while preserving image quality. This enabled abdominal scans with fewer, shorter breath-holds and better registered images.

 
2175.   Optimized refocusing flip angles for efficient single-shot fast spin echo imaging
Manojkumar Saranathan1, Andreas M Loening1, Daniel V Litwiller2, Pauline W Worters3, and Shreyas Vasanawala1
1Department of Radiology, Stanford University, Stanford, CA, United States, 2Global MR Applications and Workflow, GE Healthcare, Rochester, MN, United States, 3Global MR Applications and Workflow, GE Healthcare, Menlo Park, CA, United States

 
Single shot T2-weighted imaging methods like SSFSE and HASTE are robust to patient motion but suffer from specific absorption rate (SAR) limitations, reducing their efficiency at 3T due to lengthened TRs. We investigated the use of a variable refocusing flip angle scheme for SSFSE, which enabled significant reduction in TR while preserving image quality. This new sequence called vrfSSFSE was optimized to reduce SAR and maximize SNR for imaging the biliary/pancreatic ducts and the female pelvis and compared to conventional SSFSE imaging.

 
2176.   Comparative Analysis of Continuous Table and Fixed Table Acquisition Methods: Effects on Fat Suppression and Time Efficiency for Single-Shot T2-weighted Imaging
Puneet Sharma1, Eugene Duke2, Tulshi Bhattacharyya2, Stephan Kannengiesser3, Bobby Kalb2, and Diego R Martin2
1Medical Imaging, University of Arizona, Tucson, Arizona, United States, 2Medical Imaging, University of Arizona, Tucson, AZ, United States, 3Siemens Healthcare, Germany

 
This investigation outlines the use of continuous table movement (CTM) during the acquisition of fat-suppressed T2-weighted single-shot fast spin echo in the abdomen and pelvis. The results show that the CTM acquisition mode allows more uniform fat suppression over large z-FOV, compared to conventional multi-slice, fixed table approach. CTM also affords reduced acquisition times when scanning large anatomic coverage.

 
 

TRADITIONAL POSTER SESSION ○ BODY
Body: Kidney/GU

 
Wednesday 14 May 2014
Traditional Poster Hall  10:00 - 12:00

2177.   Improved lesion visualization using B-value maps based on thresholded DWI images
Peter Gall1, Rakesh Kasibhatla2, and Heiko Meyer1
1Siemens AG, Healthcare Sector, Erlangen, Germany, 2Siemens Technology and Services Pvt Ltd, India

 
Diffusion weighted imaging is an increasingly popular method to detect and characterize dense tissues. The detection of such tissues is often performed based on high b-value images, as they show up as bright spots over a dark background. It has been shown that computed high b-value images as helpful as measured images. In particular it is helpful to interactively define the b-value for the computation. Here a new map is proposed that enables the interaction by simple windowing and can achieve an equivalent image impression to the high b-value images.

 
2178.   Visualization of pelvic splanchnic nerve using readout-segmented echo-planar diffusion-weighted imaging at 3T: preliminary experience in healthy male volunteers.
Rikiya Yamashita1, Hiroyoshi Isoda1, Akihiro Furuta1, Seiya Kawahara1, Hironori Shimizu1, Tsuyoshi Ohno1, Shotaro Kanao1, Katsutoshi Murata2, David A. Porter3, and Kaori Togashi1
1Diagnostic Radiology, Kyoto University, Kyoto, Kyoto, Japan, 2Siemens Japan K.K., Tokyo, Japan, 3Siemens A, Healthcare Sector, Erlangen, Germany

 
The aim of this study was to evaluate the potential ability of readout-segmented echo-planar diffusion-weighted imaging for visualizing the pelvic splanchnic nerve, an important surgical landmark in pelvic nerve-preserving surgery. Eleven healthy male volunteers were examined using this novel technique at 3T, and successful visualization of the targeted nerve was achieved at the rate of 50%. Readout-segmented echo-planar diffusion-weighted imaging may be a promising technique to visualize the pelvic splanchnic nerve preoperatively in clinical settings.

 
2179.   Zoomed EPI using parallel transmission for tractography of the prostate gland without an endorectal coil: a feasibility study.
Justin M Ream1, Christopher Glielmi2, Mariana Lazar1, Naomi Campbell1, Josef Pfeuffer3, Rainer Schneider3, and Andrew B Rosenkrantz1
1Radiology, NYU Langone Medical Center, New York, NY, United States, 2Siemens Medical Solutions MR R&D, New York, NY, United States, 3Imaging and Therapy Divison, Siemens AG Healthcare Sector, Erlangen, Germany

 
While tractography of the prostate gland has previously been done only with the use of an endorectal coil, tractography using a standard pelvic phased array coil is feasible using zoomed EPI acquisition.

 
2180.   A Dedicated 3 Tesla Prostate Coil for Magnetic Resonance Elastography, Imaging, and Tracking
Wolfgang Loew1, Pelin A. Ciris2, Wei Wang2, Ehud J. Schmidt2, Charles Dumoulin1, Randy O. Giaquinto1, Clare M. Tempany-Afdhal2, and Zion T.H. Tse3
1Imaging Research Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States, 2Radiology, Brigham and Womens Hospital, Boston, Massachusetts, United States, 3Engineering, The University of Georgia, Athens, Georgia, United States

 
In this abstract a prostate coil for Magnetic Resonance Elastography (MRE) including Magnetic Resonance Imaging (MRI) and Magnetic Resonance Tracking (MRT) at 3 Tesla is presented. Details of the coil features and their benefits are described. The setup for sheer wave generation is described and tested on a phantom.

 
2181.   What a Radiologist Needs to Know: Evaluation of Hematospermia with Magnetic Resonance Imaging
Pardeep Mittal1, Sadhna Nandwana1, Kelly Cox1, Kiran K Maddu1, Juan C Camacho1, Nima Kokabi1, Courtney C Moreno1, and Bobby Kalb2
1Radiology and Imaging Sciences, Emory Uni School of Medicine, Atlanta, Georgia, United States, 2Diagnostic Radiology, University of Arizona, Tucson, Arizona, United States

 
Hematospermia (HS) is often times an anxiety provoking idiopathic self limiting condition. Potential etiologies, diagnostic work up, imaging techniques and appearance of associated pathologies will be discussed. MRI plays an important role in diagnostic work up of men with persistent hematospermia due to its superior soft tissue contrast, multiplanar capabilities and ability to resolve small caliber structures e.g. ejaculatory ducts, vasa deferentia and internal architecture of prostate in both young and older patients. Participants will gain an appreciation for the wide variety of conditions encountered in HS on MRI imaging.

 
2182.   Age dependence of 1H MRS metabolite profiles in the prostate at 1.5T and 3T
Milan Hajek1, Zuzana Ryznarova1,2, Filip Jiru1, Viktor Vik3, Roman Zachoval3, and Monika Dezortova1
1MR-Unit, Dept. Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic, 2Dept. Radiology, Thomayer Hospital, Prague, Czech Republic, 3Dept. Urology, Thomayer Hospital, Prague, Czech Republic

 
Age dependence of citrate concentration and its ratio to creatine and cholines in the prostate was studied in healthy volunteers at 1.5T and 3T MR systems using 3D CSI sequence. Coefficient of asymmetry between left and right peripheral zones was calculated. Significant increase in the citrate concentration was found between 20 and 70 years and equation parameters for age dependence of prostate metabolites were determined.

 
2183.   Generalized Factor Analysis of Dynamic MR Urography
Xiaomeng Zhang1,2, Ruth Lim1,2, Arkadiusz Sitek1,2, Jingsong Ouyang1,2, Brian Pugmire1,2, and Georges El Fakhri1,2
1Massachusetts General Hospital, Boston, MA, United States, 2Harvard Medical School, Boston, MA, United States

 
We investigate an automatic method of analysis of dynamic MR Urography (MRU) for extraction of distinct physiological compartments.

 
2184.   Using T2/T2* - contrast to characterize kidney function during a waterload examination: Initial results at 3 Tesla
Florian Lietzmann1, Philipp Krämer1, and Lothar R. Schad1
1Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Germany

 
We present an approach to measure the transversal relaxation time T2 to characterize kidney function during a water charge examination. Two healthy volunteers were included in our pilot study. Every subject had to undergo a 10h diet without any food or drink intake prior to the examinations. Data was acquired via a ROI readout in the calculated T2 maps. In conclusion, T2-BOLD-MRI is feasible and in contrast to conventional T2* BOLD-techniques the T2 measurement produce more consistent and reliable results characterizing kidney function during a waterload experiment.

 
2185.   3D Renal BOLD Imaging with a Prospectively Navigated Free Breathing Pulse Sequence
Glen Morrell1, Jeff L Zhang1, Josh Kaggie1, and Vivian S Lee1
1Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah, United States

 
We present a prospectively navigated renal BOLD sequence for free breathing full 3D BOLD imaging of the kidney. 3D renal BOLD has several advantages over 2D single slice imaging, including improved SNR, potential correction of T2* errors caused by B0 inhomogeneity, and less subjective sampling of cortex and medulla. Our sequence obtains full 3D renal BOLD data at high spatial resolution with reasonable imaging time.

 
2186.   Feasibility of noninvasive quantitative measurements of intrarenal R(2) ' in humans using an asymmetric spin echo echo planar imaging sequence.
Wu Jingyun1 and Wang Xiaoying2
1Peking University 1st Hospital, Beijing, Beijing, China, 2Peking University 1st Hospital, Beijing, Beijing, Bahamas

 
the present study is to investigate feasibility of noninvasive quantitative measurements of intrarenal R(2) ' .

 
2187.   Relative Signal Loss from Fat Using In- and Out-of-phase Images for Indicating Renal Health
Joshua D Kaggie1, Vivian S Lee1, and Glen R Morrell1
1Utah Center for Advanced Imaging Research, Radiology, University of Utah, Salt Lake City, UT, United States

 
A recent study in diabetic mice suggests a correlation between renal cortical fat content and severity of renal disease. We retrospectively evaluated the fat content of kidneys in 14 human subjects with varying degrees of renal failure ranging from normal renal function to dialysis dependence, based on in- and out-of-phase T1-weighted axial images of the kidneys. Correlation between fat content measured with the in-phase/out-of-phase images and the body mass index (BMI) or estimated glomerular filtration rate (eGFR) was investigated. We find no significant correlation between renal fat content and severity of renal disease in humans with diabetic nephropathy.

 
2188.   Arterial Spin Labeling and Diffusion Tensor Imaging of Early Kidney Changes in Pediatric Sickle Cell Disease Patients
Shannon Donnola1, Lan Lu1,2, Jane Little3, Katherine Dell4, Connie Piccone5, and Chris Flask1,6
1Radiology, Case Western Reserve University, Cleveland, Ohio, United States, 2Urology, Case Western Reserve University, Cleveland, Ohio, United States, 3Hematology and Oncology, University Hosptials-Case Medical Center, Cleveland, Ohio, United States, 4Pediatrics, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States,5Pediatrics, University Hospitals-Case Medical Center, Cleveland, Ohio, United States, 6Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, United States

 
Chronic kidney disease (CKD) is an important complication in sickle cell disease and begins in childhood. Unfortunately, current clinical measures of kidney function are insensitive to early kidney changes, a time point when therapies could be more effective. In this initial study, we used Arterial Spin Labeling and Diffusion Tensor Imaging techniques to assess kidney changes in pediatric SCD patients in comparison to healthy control subjects. Cortical Apparent Diffusion Coefficients (ADC), medullary Fractional Anisotropy (FA), and cortical perfusion were all significantly reduced in young SCD patients. These quantitative MRI techniques could potentially compliment current clinical assessments of kidney function.

 
2189.   Assessment of Response to Anti-angiogenic Targeted Therapy in Pulmonary Metastatic Renal Cell Carcinoma R2 value as a Predictive Biomarker
Guangyu Wu1 and Jianrong Xu1
1Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, »ÆÆÖÇø, ÉϺ£ÊÐ, China

 
This study was to evaluate the usefulness of magnetic resonance(MR) R2* mapping in assessing response of treatment in patients with pulmonary metastatic renal cell carcinoma receiving anti-angiogenic targeted therapy.

 
2190.   Arterial transit time-corrected renal blood flow measurement by pulsed continuous arterial spin labeling MRI: a feasibility and validation study in healthy volunteers
Kazuhiro Shimizu1, Nobuyuki Kosaka1, Yasuhiro Fujiwara1, Tsuyoshi Matsuda2, Tatsuya Yamamoto1, Tatsuro Tsuchida1, Katsuki Tsuchiyama3, Nobuyuki Oyama3, and Hirohiko Kimura1
1Department of Radiology, University of Fukui, Eiheiji, Fukui, Japan, 2Global MR Applications and Workflow, GE Healthcare Japan, Hino, Tokyo, Japan, 3Department of Urology, University of Fukui, Eiheiji, Fukui, Japan

 
We evaluated the feasibility of pulsed continuous arterial spin labeling (pcASL) MRI with multiple post-label-delay (PLD) acquisition for measuring arterial transit time (ATT)-corrected renal blood flow (ATC-RBF) in healthy volunteers. Significant differences were seen between younger and older groups in ATC-RBF and ATT, and kidney volume-corrected ATC-RBF (ATC-cRBF) correlated significantly with effective renal plasma flow (ERPF), as measured by 99mTc-MAG3 scintigraphy. However, the only moderate correlation between ATC-cRBF and ERPF suggests that further technical development may be required for RBF quantification by pcASL MRI.

 
2191.   Improvement of Renal Diffusion-Weighted MR Imaging with readout-segmented Echo-Planar Imaging at 3T
Iris Friedli1, Lindsey A Crowe1, Magalie Viallon1, Sophie de Seigneux2, and Jean-Paul Vallée1
1Radiology, Geneva University Hospital, Geneva, Switzerland, 2Nephrology, Geneva University Hospital, Geneva, Switzerland

 
The use of diffusion-weighted imaging for renal study is challenging due to limited spatial resolution, image blurring and severe geometric distortions at tissue-air, tissue-intestine interfaces. We report on the first comparison in kidney between a ‘readout segmentation of long variable echo-trains’ (Resolve) strategy with different versions of single-shot SE-EPI. A key result is the benefit of Resolve to drastically improve both the diffusion image quality by reducing susceptibility artifacts and the measurement of the Apparent Diffusion Coefficient (ADC) of the cortex and medulla.

 
2192.   Semi-automated application for kidney motion correction and filtration analysis in MR renography
Florian Rousset1,2, Clément Vachet1, Christopher Conlin3, Marta Heilbrun3, Jeff L. Zhang3, Vivian S. Lee3, and Guido Gerig1
1Scientific Computing and Imaging Institute, Salt Lake City, Utah, United States, 2CPE Lyon, Lyon, France, 3Utah Center for Advanced Imaging Research, Salt Lake City, Utah, United States

 
The glomerular filtration rate (GFR) is a crucial measurement for tailoring drug regimens and monitoring patients with liver cirrhosis via renography. Dynamic MRI presents sought contrast changes but also breathing motion, which we correct via kidney detection. We have developed a novel software offering an integrated user-friendly tool to register dynamic kidney series, select regions of interest, visualize time-varying concentration, and calculate GFR values. With 98.69% success rate in correction for motion of image frames, our tool runs on different pltaforms and provides robust registration while significantly reducing processing time and giving accurate GFR values compared to an existing software.

 
2193.   Characterizing the microstructural and architectural organization of healthy kidney tissue using diffusion tensor imaging, fiber tractography and intra-voxel incoherent motion.
Sophie van Baalen1, Alexander Leemans2, Pieter Dik1, Bennie ten Haken3, and Martijn Froeling2
1Pediatric Urology, University Medical Centre Utrecht/ WKZ, Utrecht, Netherlands, 2Imaging science institute, University Medical Centre Utrecht, Utrecht, Netherlands,3Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, Netherlands

 
For imaging of kidney pathologies, the use of endogenous contrast is important, because contrast agents can further damage renal function. MRI-DTI and IVIM are promising imaging techniques for kidney imaging because they enable to measure the extent and direction of water diffusion and the perfusion fraction, respectively. In this study we used MRI-DTI and IVIM to visualize the microstructural properties of kidney tissues. With MRI-DTI and tractography, the radially orientation of the tubules and vascular network in the renal medulla is reflected by radially oriented tracts, originating in the cortex and convolving in multiple papillae. With IVIM, blood perfusion and urine diffusion fractions can be visualized for different kidney tissues.

 
2194.   Renal Perfusion Imaging with Pseudo-continuous Arterial-Spin Labelling (pCASL) at 3.0T: Repeatability in Healthy volunteers.
Magdalena Sokolska1, David Thomas2, Alan Bainbridge1, Xavier Golay2, Stuart Taylor3, Shonit Punwani3, and Douglas Pendse3
1UCH Medical Physics and Bioengineering, London, London, United Kingdom, 2UCL Institute of Neurology, London, London, United Kingdom, 3Centre for Medical Imaging, UCL, London, United Kingdom

 
Renal diseases are associated with abnormalities in renal perfusion. Furthermore, characterisation of focal renal lesions such as carcinomas is dependent on the assessment of renal vascularity. Traditionally renal perfusion imaging has relied on contrast agents, which are nephrotoxic. Arterial Spin Labelling (ASL) allows for the assessment renal perfusion without contrast agent injection. Furthermore ASL offers quantification of renal blood flow (RBF) which may be a useful imaging biomarker. This work aims to assess repeatability of pseudo-continuous ASL1 (pCASL) in healthy volunteers.

 
2195.   Detection of intracellular lipid in adrenal adenomas - a direct intra-individual comparison of chemical shift imaging of adrenal lesions imaged at both 1.5T and 3T.
Justin M Ream1, Byron Gaing1, Thais C Mussi2, and Andrew B Rosenkrantz1
1Radiology, NYU Langone Medical Center, New York, NY, United States, 2Hospital Israelita Albert Einstein, Sao Paolo, Brazil

 
Chemical shift MRI has an integral role in detecting intracellular lipid in adrenal adenomas, although most published data has utilized 1.5 Tesla imaging. The purpose of this study is to compare chemical shift imaging at 1.5T and 3T imaging within the same set of adrenal lesions in order to perform a direct intra-individual comparison of 1.5T and 3T imaging in diagnosing adrenal adenomas.

 
2196.   Optimal measurement of arterial input function in MR renography using saturation recovery
Christopher C. Conlin1, Jeff L. Zhang1, Marta E. Heilbrun1, Kristi Carlston1, Daniel Kim1, Kathryn A. Morton1, and Vivian S. Lee1
1Department of Radiology, University of Utah, Salt Lake City, Utah, United States

 
This study compares long and short inversion times (TIs) for measuring arterial input functions (AIFs) from saturation recovery images in the estimation of glomerular filtration rate (GFR) from low dose Gd-enhanced MR renography. Long TIs may result in saturated signal and therefore an inaccurate estimate of Gd concentration which is required for GFR calculation. Short TIs may suffer from low SNR. By comparing GFR estimates obtained at short and long TIs to reference measurements from 99mTc-DTPA clearance, it was found that relatively long TIs should be used to avoid accumulation of AIF error into the estimated GFR.

 
2197.   MRI Provides More Accurate Renal Motion Estimation than 4D-CT for Radiation Treatment Planning in Young Children
Adam M Winchell1,2, Atmaram Pai Panandiker1, Ruitian Song1, Ralf B Loeffler1, and Claudia M Hillenbrand1
1Radiological Sciences, St. Jude Children’s Research Hospital, Memphis, TN, United States, 2Biomedical Engineering, University of Memphis, Memphis, TN, United States

 
In this study, we measured respiratory induced kidney motion in young children with abdominal neuroblastoma using both 4D-CT and real-time MRI to evaluate tracking accuracy. Real-time MRI provides a more desirable tissue contrast of the kidney and had about two times higher spatial resolution in the superior/inferior direction compared to 4D-CT which enabled superior demarcation of organ boundaries, anatomical tracking, and improved accuracy.

 
2198.   Ultra Low Dose Free breathing Quantitative Renal Perfusion and Filtration using 3D Through-time Radial GRAPPA
Katherine L. Wright1, Yong Chen2, Mark A. Griswold1,2, Nicole Seiberlich1, and Vikas Gulani1,2
1Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, United States, 2Radiology, Case Western Reserve University, Cleveland, Ohio, United States

 
This work demonstrates 3D quantitative renal DCE MRI using half and quarter doses (by weight) of a gadolinium based contrast agent and no breath-holds. Data are acquired with a highly accelerated stack-of-stars acquisition, reconstructed using 3D through-time radial GRAPPA, and registered to remove respiratory motion. This exam provides 3D quantification of perfusion, filtration, and mean transit times at clinically relevant spatial resolutions using very low doses of contrast agent.

 
2199.   Evaluation of the temporal variation of diffusion and micro-perfusion in cisplatin induced rodent renal fibrosis models using multi-b diffusion weighted MR imaging
Haoran Sun1, Huanhuan Wu1, and Ziheng Zhang2
1Radiology, Tianjin Medical University Hospital, Tianjin, Tianjin, China, 2MR Research China, GE Healthcare, Shanghai, Shanghai, China

 
Intravoxel incoherent motion (IVIM) DWI has recently shown potential to assess functional changes of renal fibrosis. From the findings through multi-b DW-MRI measurements on cisplatin induced rodent renal fibrosis models, the temporal variation of ADC values behaved as a weight of the true diffusion and pseudo-diffusion. The biomarkers resulted from mono-exponential model exhibited a dual phase temporal variation, while those from bi-exponential model remained a single tendency of variation. According to the histopathological observation that the worsening of renal fibrosis with time, the bi-exponential model might be a better choice for an accurate indication of the evolution of renal fibrosis.

 
2200.   Imaging Glomeruli in a Clinical MRI System at 3 T
Jorge Chacón-Caldera1, Philipp Krämer1, Sebastian Domsch1, Stefania Geraci2, Norbert Gretz2, and Lothar R Schad1
1Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Germany, 2Medical Research Center, Heidelberg University, Mannheim, Germany

 
The number of glomeruli in kidneys is associated with kidney diseases. There is interest to discover if glomerular quantification in humans is possible. Currently, glomerular imaging with MRI is achieved using in vitro samples in preclinical systems with main magnetic fields of minimum 7T. This work presents the first ever glomerular images acquired with a clinical scanner at 3T. We used two cationazed-ferritin labeled rat kidneys and a Siemens Magnetom to demonstrate that currently available clinical scanners are capable of performing glomerular imaging. The parameters were also used to assess the current standpoint towards future human kidney measurements.

 
2201.   Quantitative Assessment of Renal T2* Heterogeneity with Minkowski Functionals for the Detection of Ischemia/Reperfusion Injury
Andreas Pohlmann1, Jan Hentschel1, Karen Arakelyan1, Mandy Fechner2, Uwe Hoff2, Gordana Bubalo2, Kathleen Cantow3, Sonia Waiczies1, Duska Dragun2, Bert Flemming3, Erdmann Seeliger3, and Thoralf Niendorf1
1Berlin Ultrahigh Field Facility, Max Delbrueck Center for Moleculare Medicine, Berlin, Germany, 2Nephrology and Intensive Care Medicine, Campus Virchow-Klinikum and Center for Cardiovascular Research, Charite-Universitaetsmedizin Berlin, Berlin, Germany, 3Institute of Physiology and Center for Cardiovascular Research, Charité Medical Faculty, Berlin, Germany

 
Imbalance between renal tissue oxygen demand and supply is a pivotal element in the pathophysiologic cascade of ischema/reperfusion injury. Parametric mapping of renal T2*, which is known to be blood oxygenation level dependent, to monitor I/R in rats if feasible, however, comparison of absolute renal T2* is barely feasible, because absolute values depend on magnetic field strength, B0 homogeneity, etc. By applying image heterogeneity analysis by 2D Minkowski functionals to renal T2* data we investigated whether renal T2* heterogeneity analysis allows a differentiation between healthy naïve kidneys, ischemic kidneys, and kidneys during subsequent reperfusion.

 
2202.   Contrast/SNR optimization for the Imaging of Cationized-Ferritin labeled Glomeruli at 9.4T
Jorge Chacón-Caldera1, Raffi Kalayciyan1, and Lothar R Schad1
1Computer Assisted Clinical Medicine, University of Heidelberg, Mannheim, Germany

 
Imaging whole kidney volumes to visualize glomeruli with MRI requires long acquisition times. Wrong parameters selection can reduce or even impede the visualization of the glomeruil. In this work we present quick measurements of effective transverse relaxation time (T2*) in the kidney cortex and cationized-ferritin labeled glomeruli at 9.4T in mouse kidneys. The contrast between them was also calculated for the whole range of measured echo times. These measurements can be easily extrapolated and/or replicated in other systems and field strengths to facilitate the glomerular imaging, reduce the scanning times and improve the accuracy and efficiency of possible glomerular quantifications.

 
2203.   Non-invasively Quantitative Measurements of Intrarenal Oxygen Extraction Fraction (OEF) in Rabbits with Unilateral Renal Artery Stenosis Using MRI
Xiaodong Zhang1, Yue Mi2, Jing Wang3, Jingyun Wu1, Kai Zhao1, Jian Luo1, Xuedong Yang1, Xiaoying Wang1,4, Jue Zhang4, and Hongyu An5
1Department of Radiology, Peking University First Hospital, Beijing, Beijing, China, 2Department of Urology, Peking University First Hospital, Beijing, Beijing, China, 3School of physics, Peking University, Beijing, Beijing, China, 4Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, Beijing, China, 5Department of Radiology and Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States

 
Quantitative measurement of renal oxygenation is of central importance in understanding and treating renal diseases and oxygen extraction fraction (OEF) can provide a valid criterion for evaluation the tissue oxygen metabolism under both normal and disease states. According to the Yablonskiy and Haacke’s biophysical analytical model, the intra-renal OEF can be estimated using a multi-echo gradient and spin echo (MEGSE) sequence. In this study, we will demonstrate the ability to obtain quantitative estimates of intra-renal OEF noninvasively in normal and unilateral renal artery stenosis rabbits of the Multi-Echo Gradient and Spin Echo (MEGSE).

 
2204.   Ferumoxytol Enhanced Steady-State MRI Reveals Renal Blood Volume Decrease During Aortic Occlusion
Andreas Pohlmann1, Jan Hentschel1, Karen Arakelyan1, Stefanie Kox1, Sonia Waiczies1, Bert Flemming2, Erdmann Seeliger2, and Thoralf Niendorf1
1Berlin Ultrahigh Field Facility, Max Delbrueck Center for Moleculare Medicine, Berlin, Germany, 2Institute of Physiology and Center for Cardiovascular Research, Charité Medical Faculty, Berlin, Germany

 
Acute kidney injuries (AKI) of various origins share one common feature: imbalance between local tissue oxygen delivery and demand. Changes in tissue pO2 and T2* may be closely related, however, their link could be influenced by variations in blood volume fraction. We hypothesized that monitoring of RBV could provide evidence for a significant RBV reduction during aortic occlusion, and hence for the relevance of RBV when interpreting renal T2*. To test our hypothesis we established RBV estimation with ferumoxytol at 9.4 Tesla in rats and compared the effects of renal arterio-venous occlusion with suprarenal aortic occlusion while monitoring renal T2*.

 
2205.   High resolution ex-vivo imaging of a rodent kidney with a portable MR-Scanner at 0.5 Tesla: Initial results in relation to state of the art techniques
Florian Lietzmann1, Christina Hopfgarten1, Jorge Chacón-Caldera1, Stefania Geraci2, and Lothar R. Schad1
1Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Germany, 2Medical Research Center, Heidelberg University, Mannheim, Germany

 
Renal imaging using MRI is crucial but not available to many institutions because until now it relied in high-end systems working at high or ultra high field strengths. As an alternative, a low-field portable MR-system which can achieve similar resolutions like a small animal system can provide images with the demanded resolution. Purpose of this work is an initial comparison of the image quality of an acquisition with the low field system to the state of the art methods. In all images a distinction between the different tissue compartments is possible. In conclusion, high resolution imaging of the kidney need not necessarily be performed on high field systems. The portable MR system reaches a sufficient resolution for the distinction of different renal compartments as well as the identification of an inner structure of the renal cortex.

 
2206.   Parametric Mapping of Renal T2* Demonstrates Beneficial Effect of Epoxyeicosatrienoic Acid for Preventing Acute Kidney Injury
Andreas Pohlmann1, Jan Hentschel1, Uwe Hoff2, Gordana Bubalo2, Mandy Fechner2, Maximilian Blum3, Ye Zhu2, Karen Arakelyan1,4, Erdmann Seeliger4, Bert Flemming4, Dennis Gurgen2, Wolfgang Schneider3, Michael Rothe5, Vijaya L Manthati6, John R Falck6, Wolf-Hagen Schunck3, Duska Dragun2, and Thoralf Niendorf1
1Berlin Ultrahigh Field Facility, Max Delbrueck Center for Moleculare Medicine, Berlin, Germany, 2Nephrology and Intensive Care Medicine, Campus Virchow-Klinikum and Center for Cardiovascular Research, Charite-Universitaetsmedizin Berlin, Berlin, Germany, 3Experimental and Clinical Research Center, Charite Medical Faculty and the Max Delbrueck Center for Molecular Medicine, Berlin, Germany, 4Institute of Physiology and Center for Cardiovascular Research, Charité Medical Faculty, Berlin, Germany,5Lipidomix GmbH, Berlin, Germany, 6Biochemistry Department, UT Southwestern, Dallas, TX, United States

 
Current therapeutic options for treating acute kidney injury (AKI) are disappointing and hence the need for establishing druggable targets. Imbalances in cytochrome P450 (CYP)-dependent eicosanoid formation may play a central role in AKI. Imbalance between renal oxygen demand and supply is considered to be the initiating step in the pathophysiologic cascade of events. In this study we investigated whether administration of an epoxyeicosatrienoic acid (EET) agonist improves renal reoxygenation during the initial 2 h reperfusion phase. Parametric mapping of renal T2* demonstrated improved renal re-oxygenation after EET treatment. EET agonists may provide novel therapeutic options for prevention of ischemic AKI.

 
2207.   Assessment of Renal Inflammatory Cell Infiltration in a Murine ANCA-Induced Glomerulonephritis Model by 19F-MRI
Andreas Pohlmann1, Adrian Schreiber2, Min-Chi Ku3, Helmar Waiczies4, Stefanie Kox1, Ralph Kettritz2, Sonia Waiczies1, and Thoralf Niendorf1,5
1Berlin Ultrahigh Field Facility, Max Delbrueck Center for Moleculare Medicine, Berlin, Germany, 2Clinic for Nephrology and Intensive Care Medicine, Campus Virchow, Charité Medical Faculty, Berlin, Germany, 3Berlin Ultrahigh Field Facility, Max Delbrueck Center for Molecular Medicine, Berlin, Germany, 4MRI.TOOLS GmbH, Berlin, Germany, 5Experimental and Clinical Research Center, Charite Medical Faculty and the Max Delbrueck Center for Molecular Medicine, Berlin, Germany

 
Anti-neutrophil cytoplasmic antibodies (ANCA) are responsible for the development of small vessel vasculitis. Currently, diagnosis of the initial inflammation and its recurrences relies on kidney biopsies, hence, the clinical need for non-invasive methods. We have employed multi-modal fluorescently (DiI) and 19F labeled nanoparticles to identify specific inflammatory cell populations tested the hypothesis that 19F MRI after in-vivo 19F-labeling of monocytes and neutrophils allows non-invasive detection of ANCA-induced renal inflammation. Our data suggest that 19F-MRI may represent a novel non-invasive method for the assessment of renal inflammation in mouse models with the potential of translation into a clinical tool for the diagnosis of glomerulonephritis in patients.

 
2208.   High Resolution Hyperpolarized 13C Urea MRI Renography
Galen D Reed1, Cornelius von Morze1, Bertram L Koelsch1, Myriam M Chaumeil1, Alan S Verkman2, Sabrina M Ronen1, Robert A Bok1, Jeff M Sands3, Peder E Larson1, Jan Henrik Ardenkjaer-Larsen4, John Kurhanewicz1, and Daniel B Vigneron1
1Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, United States, 2Nephrology, University of California San Francisco, San Francisco, California, United States, 3Department of Medicine, Renal Division, Emory University, Atlanta, Georgia, United States, 4Electrical Engineering, Technical University of Denmark, Lyngby, Denmark

 
Urea is a key osmolyte that plays a crucial role in kidney function. In this study, we present a hyperpolarized 13C MRI method for imaging urea within the renal tubules and collecting system at 1.2 mm isotropic resolution. This method utilizes the increased urea T2 from 15N labeling combined with specialized 3D SSFP acquisition and the very large 13C urea T2 contrast observed between the kidney and vasculature. Relaxometry experiments revealed this long-T2 signal reports on urea that has passed through the glomerulus, thus enabling renal urea filtration as a source of image contrast.

 
2209.   
Effect of Anesthesia on Renal R2* Measured by BOLD MRI
David J Niles1, Jeremy W Gordon1, and Sean B Fain1,2
1Medical Physics, University of Wisconsin, Madison, WI, United States, 2Radiology, University of Wisconsin, Madison, WI, United States

 
Anesthesia produces several physiologic effects in the kidney, including changes of blood flow, glomerular filtration, and sodium excretion. Because R2* is influenced by hemodynamic parameters and oxygenation, its value may differ depending on the choice and dosage of anesthetic agent used during imaging. We measured renal R2* in mice anesthetized with five common anesthetics and observed strong dependence of R2* on the choice of agent. Differences in R2* between inhaled and injected agents was not explained by differences in inspired oxygen fraction. We conclude that the effects of anesthetic agent should be considered when designing and evaluating BOLD MRI studies.

 
2210.   New Magnetic Nanoparticle for Kidney Function
Yoshichika Yoshioka1,2, Ting Chen1, Yuki Mori1,2, Zhenyu Cheng1, Yuuto Kashiwagi1, Masaki Fukunaga2,3, Ikuhiro Kida1,2, Yoshiyuki Tago4, Shinichi Yoshida4, and Kohji Ohno5
1Immunology Frontier Research Center (IFReC), Osaka University, Suita, Osaka, Japan, 2Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT) and Osaka University, Suita, Osaka, Japan, 31Immunology Frontier Research Center (IFReC), Osaka University, Suita, Osaka, Japan, 4Frontier Biochemical and Medical Research Laboratories, Kaneka Corporation, Takasago, Hyogo, Japan, 5Institute for Chemical Research, Kyoto University, Uji, Kyoto, Japan

 
The biodistribution pattern of newly synthesized magnetic nano particles was investigated in mice. The particles are taken little by Kupffer cells and peripheral macrophages and have the long half-life in mouse blood circulation. The particles showed the marked distribution pattern especially in the mouse kidney. The particles retained much in the renal cortex and in the boundaries between cortex and medulla and between outer medulla and inner medulla. The dark round spots in the renal cortex were confirmed as renal corpuscles. These distribution patterns could be used as a measure of renal functions.

 
2211.   Accurate Mouse Kidney Morphology with Glomerulus-Targeted Contrast Agents
Edwin Baldelomar1, Scott Beeman2, Luise Cullen-McEwen3, Jennifer R Charlton4, John F. Bertram3, and Kevin M. Bennett5
1Department of Physics, University of Hawai'i at Manoa, Honolulu, Hawaii, United States, 2Radiology, Washington University School of Medicine, St Louis, Missouri, United States, 3Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria, Australia, 4University of Virginia Medical Center, Charlottesville, Virginia, United States, 5Department of Biology, University of Hawai'i at Manoa, Honolulu, Hawaii, United States

 
MRI has previously been shown to be a viable tool to establish nephron endowment in intact kidneys using super paramagnetic, glomerulus specific, cationic ferritin (CF). Along with nephron number, glomerular size may also be measured be with MRI. This work takes into account susceptibility of super paramagnetic CF labeling in 3D T2* gradient echo MRI to correct volume measurements from MRI to establish accurate, non-invasive, kidney morphology measurements in mice.

 
2212.   
Multiparametric functional MRI for assessment of acute renal allograft rejection in mice – correlation with renal histology and the composition of T-cell infiltrates
Katja Hueper1,2, Song Rong3, Marcel Gutberlet1,2, Matti Peperhove1, Susanne Tewes1, Amelie Barrmeyer1, Martin Meier4, Sibylle von Vietinghoff3, Michael Mengel5, Hermann Haller3, Frank Wacker1,2, Dagmar Hartung1,2, and Faikah Gueler3
1Radiology, Hannover Medical School, Hannover, Germany, 2REBIRTH Cluster of Excellence, Hannover Medical School, Hannover, Germany, 3Nephrology, Hannover Medical School, Hannover, Germany, 4Institute of Animal Science, Hannover Medical School, Hannover, Germany, 5Alberta Transplant Applied Genomics Centre, University of Alberta, Edmonton, Alberta, Canada

 
We investigated whether multiparametric functional MRI allows evaluation of renal allograft rejection in mice. An acute rejection was induced by allogenic kidney transplantation; animals after isogenic transplantation were used as controls. Three weeks after transplantation renal perfusion (ASL), T1-/ T2-relaxation times and ADC-values were determined using a 7T-scanner. Animals after allogenic transplantation developed an acute T-cell-mediated rejection. In these animals, renal perfusion impairment was stronger, T1- and T2-values were higher and ADC was lower compared to animals after isogenic transplantation. Functional MRI-parameters significantly correlated with the extent of T-cell-infiltrates. Thus, functional MRI may improve non-invasive diagnosis of renal allograft rejection.

 
2213.   MicroMR Imaging of Renal Interstitial Fibrosis in a Unilateral Ureteric Obstruction Model
Septian Hartono1,2, Tong San Koh1, In Chin Song3, Lin Zheng3, Wing Sum Lee3, Laurent Martarello4, and Choon Hua Thng1
1National Cancer Centre Singapore, Singapore, Singapore, Singapore, 2Nanyang Technological University, Singapore, Singapore, Singapore, 3SingHealth Experimental Medicine Centre, Singapore, Singapore, 4Roche Translational Medicine Hub, Singapore, Singapore

 
We aim to determine if DCE-MRI and DWI can detect renal interstitial fibrosis in mice. Renal fibrosis is induced by unilateral ureteric obstruction (UUO) with survival surgery. Six mice were scanned before the UUO procedure dan one week after the UUO. Renal fibrosis is quantified by amount of fibrosis as measured by Sirius Red stain. There is a drop of ADC as derived from DWI and renal parenchymal mean transit time (PMTT) as derived from DCE-MRI in the cortices of the ligated kidneys. PMTT correlated significantly with % of Sirius Red, signifying potentials of using DCE-MRI as biomarker of renal fibrosis.

 
2214.   Quantification of Iron Oxide Nanoparticles in a large animal model using MRI
Oliviero L Gobbo1, Andrew J Fagan2, Colin Ryan3, Deirdre Edge4, Christine Shortt4, Marek Radomski3, Adriele Prina-Mello5, Farouk Markos4, and Yuri Volkov5
1School of Pharmacy and Pharmaceutical Sciences and TCIN, Trinity College Dublin, Dublin, Leinster, Ireland, 2Centre for Advanced Medical Imaging (CAMI), St James’s Hospital / Trinity College Dublin, Dublin, Ireland, 3School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin, Ireland, 4Physiology Department, University College Cork, Cork, Ireland, 5School of Medicine, Trinity College Dublin, Dublin, Ireland

 
MULTIFUN consortium's current goal is to develop and validate multifunctional SPION for the early detection and treatment of breast and pancreatic cancer while reducing side effects for patients compared to conventional treatment with anti-cancer drugs. This joint therapeutic and diagnostic property has been called “theranostic”. Our study establishes an MRI protocol for the quantification of SPIONs in ex-vivo pig organs (i.e. kidneys) which can potentially be used in preclinical cancer research and in translational medicine.

 
 

TRADITIONAL POSTER SESSION ○ BODY
Body: Pelvis/Kidney

 
Wednesday 14 May 2014
Traditional Poster Hall  10:00 - 12:00

2215.   A preliminary study of multi-b-value DWI in cervical cancer with different pathological features
jie zhang1, huadan xue2, zhengyu jin2, and ziheng zhang3
1PUMCH, Beijing, Beijing, China, 2PUMCH, Beijing, China, 3MR Research China, GE Healthcare, Beijing, China

 
In the study the capability of using the ADC values depicting pseudo-perfusion and diffusion respectively resulted from a bi-exponential model to discriminate cervical squamous cell cancer and cervical adenocarcinoma, which feature similar clinical symptoms, in a multi-b diffusion weighted MR imaging measurement. A smaller ADCslow value of cervical squamous cell carcinoma and larger ADCfast and Ffast values of cervical squamous cell carcinoma respectively vs. counter-part were found. To differentiation the grades of both the cervical squamous cell carcinoma and cervical squamous cell carcinoma respectively using the ADCslow, and ADCfast and Ffast values show no significant positive results in the measurements.

 
2216.   Effect of chemoradiation on cervical cancer tumor oxygenation, using Blood Oxygen Level Dependent (BOLD) MRI
James J Brittin1, Elizabeth A Sadowski1, Kristin A Bradley2, Emily F Dunn2, and Jessica B Robbins1
1Radiology, University of Wisconsin, Madison, Wisconsin, United States, 2Radiation Oncology, University of Wisconsin, Madison, Wisconsin, United States

 
BOLD MRI sequences can non-invasively measure oxygen bioavailability in different tissues throughout the body, including the uterine cervix. In our retrospective study involving 11 patients with cervical cancer, we found that treatment with chemoradiation, including high dose intracavitary brachytherapy resulted in decreased cervical tumor oxygenation (P=0.001), possibly due to reduced angiogenesis, reduced tumor volume, and/or increased fibrotic tissue formation. As tumor hypoxia has been shown to be a powerful prognostic indicator for poor outcomes in cervical cancer as well as multiple other malignancies, BOLD MRI may be useful in differentiating between tumors which will and will not be radiosensitive.

 
2217.   Toward quantitative biomarkers of cervical structural health: development of MRI tools for in-vivo mechanical property measurement.
Michael Fernandez1, Sachin Jambawalikar2, and Kristin Myers1
1Mechanical Engineering, Columbia University, New York, NY, United States, 2Radiology, Columbia University Medical Center, New York, NY, United States

 
The mechanical properties of cervical tissue and cervical geometry are crucial factors in the ability of the cervix to withstand mechanical loading from the fetus during the course of pregnancy. Transport of interstitial fluid inside hydrated tissue such as cervical stroma plays an important role in its mechanical response. Permeability is a mechanical property that characterizes bulk fluid transport within a hydrated tissue or material undergoing mechanical loading. The purpose of this study was to explore the coupled relationship between the diffusive properties of a hydrated material (via ADC) as measured by MRI and its corresponding hydraulic permeability measured in-vitro. These results for polyacrylamide hydrogels are a foundation for the characterization of similar relationships in human cervical tissue which can potentially be used as quantitative clinical biomarkers for cervical mechanical properties and preterm birth risk.

 
2218.   Texture analysis of 3T high resolution T2 weighted images in ovarian cystadenoma versus borderline tumour.
Martine Dujardin1, Peter Gibbs1, and Lindsay W Turnbull1
1Centre for MR Investigations, University of Hull in association with Hull York Medical School, Hull, United Kingdom

 
Preoperative MR differentiation of borderline ovarian tumour (BOT) from cystadenoma allowing optimal surgical management is important, however challenging. This study investigates the ability of texture analysis (16 textural descriptors) applied to 3T-based high resolution T2-weighted images to distinguish between both lesion types. f14 (maximal correlation coefficient) showed a significant difference between adenoma and BOT (p=0.02; AUC=0.7).

 
2219.   Can Magnetic Resonance Spectroscopy reflect the Aggressiveness of Endometrial cancer?
Jie Zhang1, Qingwei Liu1, Shifeng Cai1, Changzhong Li2, Xichao Sun3, and Caixia Fu4
1Radiology, Shandong Provincial Hospital, Shandong University, Jinan, Shandong, China, 2Obstetrics and Gynecology, Shandong Provincial Hospital, Shandong University, Jinan, Shandong, China, 3Pathology, Shandong Provincial Hospital, Shandong University, Jinan, Shandong, China, 4Siemens Shenzhen Magnetic Resonance Ltd., Shenzhen, Guangdong, China

 
This study was to investigate whether the choline-containing compounds (Cho) obtained from three-dimension 1H MRS with 3T system is associated with the aggressiveness of endometrial cancer (ECa). Thirty-eight patients with ECa and 19 patients with benign lesions in endometria or in submucosa (BLs-ESm) were included in this study. The ratio of sum of Cho to sum of water (Cho/water) was the statistical unit. The Cho/water can differentiate ECa from BLs-ESm and differentiate type II from type I ECa, but can¡¯t differentiate different stages ECa, as well as different grades ECa. Cho/water increased with the increase of tumor stage and size.

 
2220.   Value of Star Map for assessing cystic ovarian tumors
Michiko Kabayashi1, Yoshiko Hayashida1, Hodaka Oki1, Athushi Ogasawara1, Keita Watanabe1, Satoru Ide1, Shingo Kakeda1, Takatoshi Aoki1, and Yukunori Korogi1
1Radiology, University of Occupational and Environmental Helth School of Medicine, Kitakyushu, Fukuoka, Japan

 
The purpose of our study was to evaluate the utility of Star Map for diagnose of cystic ovarian tumors. 25 patients with pathologically proven ovarian tumors were included in this study. The regions of interest (ROIs) were manually drawn as big as it could be on Star map in areas corresponding to the non-enhancing area. The areas showed high signal intensity on T1WI of ovarian tumors also evaluated. Our results suggested that StarMap could be a helpful tool for diagnosis of ovarian tumors.

 
2221.   The usefulness of the apparent diffusion coefficient value for the differentiation between ovarian polypoid endometriosis and ovarian endometrioma with malignant tumor
Eito Kozawa1, Masahiro Takahashi2, Yusuke Watanabe2, Masanori Yasuda2, Keiichi Fujiwara2, and Fumiko Kimura2
1Saitama Medical University,International Medical Center, Hidaka-shi, Saitama, Japan, 2Saitama Medical University, International Medical Center, Saitama, Japan

 
The apparent diffusion coefficient (ADC) has been reported useful in the qualitative diagnosis of tumors and changes that occur as a result of treatment. ADC value is well accepted as a means to differentiate between malignant and benign tumor. It is difficult differentiate between ovarian polypoid endometriosis (OPE) and ovarian endometrioma with malignant tumor (OEMT) because both the tumors contained solid components. We evaluated ADC values whether we could differentiate between OPE and OEMT.

 
2222.   Texture and Regression Tree Analysis in the Characterisation of Ovarian Lesions
Peter Gibbs1, Martine Dujardin1, and Lindsay Turnbull1
1MRI Centre, HYMS at University of Hull, Hull, East Yorkshire, United Kingdom

 
MRI is the preferred technique for characterising complex adnexal masses. However, the presence of solid components in both benign and malignant lesions causes diagnostic difficulties. In this work the utility of co-occurrence matrix based textural analysis in the diagnosis of ovarian malignancy is explored. Significant differences between four groups (ovarian cancer, borderline ovarian tumour, cystadenoma and cystadenofibroma) were found for 8 of 16 calculated texture parameters. Regression tree analysis yielded a robust diagnostic model, based on 3 texture parameters, with an overall accuracy of 70%.

 
2223.   Segmentation and Visualization of Brain and Lung volumes in fetal MRI using Active Contours and Morphological Operators
shivaprasad ashok chikop1, sneha Shiradon1, Pavan Poojar1, Arush Honnedevasthana Arun1, Madhu Sudan Muguru Prabhuswamy1, Sona Pungavkar2, and Sairam Geethanath1
1Medical Imaging Research Centre, Dayananda Sagar Institutions, bangalore, Karnataka, India, 2Department of Radiology, Dr.Balabhai Nanavathi Hospital, Mumbai, Maharastra, India

 
Computation of fetal brain and lung volume significantly aid in biomarker determination to monitor fetal development for diagnosis and/or prognosis of fetal pathologies. The algorithm does not depend on priors based on intensity and can be used to perform segmentation on T1/T2 contrast. The result shows significant correlation between automated brain, semi-automated lung segmentation with corresponding manual segmentations as quantified by number of segmentation pixels and qualitatively through segmentation results visualized as 3D volumes. Current and future work includes optimization of brain and lung volume visualization for more datasets and obtaining biomarkers to distinguish normal and abnormal fetal pathology.

 
2224.   Ultrafast Fetal MR Imaging using Interpolated Compressed Sensing
Yong Pang1, Jindai Jiang2, and Xiaoliang Zhang1,3
1Radiology & Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States, 2Department of Radiology, 2nd Hospital of Guangzhou Medical University, Guangzhou, China, 3UCSF/UC Berkeley Joint Graduate Group in Bioengineering, San Francisco & Berkeley, CA, United States

 
Fetal MRI provides detailed fetal anatomy and is being increasingly used to evaluate fetal development. However, the image quality is degraded by the fetal motion and maternal respiratory and involuntary movements during long acquisition time. In this study, we applied the interpolated compressed sensing method to accelerate the acquisition and increase contrast to noise ratio (CNR) for multi-slice two-dimensional MR imaging. By combining with parallel imaging, the acquisition time can be further reduced. In-vivo MR of a pregnant woman has been used to investigate the feasibility of this method, showing obviously increased CNR compared with the conventional CS.

 
2225.   1H MRS as a Biomarker for Placental Insufficiency in the Growth Restricted Fetus
Gillian Macnaught1, Scott Semple1,2, Calum Gray1,3, Mary Simpson4, Jane Norman4, Jane Walker5, and Fiona Denison4
1Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, Scotland, United Kingdom, 2Centre for Cardiovascular Sciences, University of Edinburgh, Edinburgh, Scotland, United Kingdom, 3Wellcome Trust Clinical Research Facility, University of Edinburgh, Edinburgh, Scotland, United Kingdom, 4Tommy's Centre for Maternal and Fetal Health, University of Edinburgh MRC Centre for Reproductive Health, Edinburgh, Scotland, United Kingdom, 5Simpson Centre for Reproductive Health, Edinburgh Royal Infirmary, Edinburgh, Scotland, United Kingdom

 
Placental insufficiency commonly leads to Fetal Growth Restriction (FGR) and stillbirth. The current recommendation is to deliver the baby prematurely which is not without risk. We present proton placenta spectra acquired in-utero of 4 FGR and 4 normal pregnancies, acquired on a 3T Siemens Verio MR system using the PRESS technique. Spectra were analysed using JMRUI. The ratios of glutamine and glutamate (Glx) to choline (cho) in the placentas of 4 FGR pregnancies were lower than in their gestation-matched controls. This may provide an in vivo marker of placental function in these difficult to manage cases.

 
2226.   Evaluating placental growth in normal murine pregnancy using tissue-similarity-mapping and dynamic contrast enhanced magnetic resonance imaging
Brijesh Kumar Yadav1,2, Uday Bhaskar Krishnamurthy1,2, Yimin Shen1, Jaladhar Neelavalli1,2, Gabor Szalai3, Bing Wang3, Tinnakorn Chaiworapongsa3,4, Edgar Hernandez-Andrade3,4, Nandor Gabor Than3,4, Ewart Mark Haacke1,2, and Roberto Romero3
1Department of Radiology, Wayne State University, Detroit, Michigan, United States, 2Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, United States, 3Perinatology Research Branch, NICHD, NIH, DHHS., Wayne State University, Detroit, Michigan, United States, 4Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, United States

 
In this study, the longitudinal variations in the size of high perfusion and low perfusion zones of the normal murine placenta along different gestational ages are quantified using dynamic contrast enhancement magnetic resonance imaging(DCE-MRI) and an automatic segmentation method based on Tissue Similarity Mapping (TSM.

 
 

TRADITIONAL POSTER SESSION ○ BODY
Body: Diabetes/DWI/IMRS

 
Wednesday 14 May 2014
Traditional Poster Hall  10:00 - 12:00

2227.   Systematic study of signal models for fat quantification at 3T using chemical shift imaging
Sonia Isabel Goncalves1, Mario Ribeiro2, Filipe Caseiro-Alves3, and Miguel Castelo-Branco1
1IBILI-Faculty of Medicine, University of Coimbra, Coimbra, Coimbra, Portugal, 2Faculty of Sciences and Technology, University of Coimbra, Coimbra, Portugal, 3Faculty of Medicine, University of Coimbra, Coimbra, Portugal

 
Liver fat fraction (FF) quantification is an important tool that can help staging non-alcoholic fatty liver disease. The gold-standard procedure for FF quantification, is percutaneous biopsy, which is expensive and prone to post-surgical complications. Non-invasive alternatives include magnetic resonance spectroscopy and chemical shift imaging (CSI) using multi-echo gradient-echo (ME-GRE) pulse sequences. The latter method is very appealing because data acquisition is typically fast and well tolerated by patients.Models based on the analysis of magnitude and complex data have been used to separate water and fat components from ME-GRE images and several studies have been dedicated to advantages and disadvantages of each.Despite all the advances, the fact remains that clinical applications of FF quantification using CSI largely overlook these aspects. In this paper, we provide a systematic analysis of different signal models to quantify FF at 3T using ME-GRE pulse sequences with twelve echoes, with a view on optimizing the combination of echo times (TEs). We furthermore study the influence of magnetic field heterogeneities in the accuracy of the complex model for FF estimation.

 
2228.   High resolution MRI of the mouse mammary gland
Thomas Neuberger1,2, Sooyeon Lee3, Gangchea Lee2, and Shannon Kelleher3
1Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, United States, 2Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, United States, 3Department of Nutritional Sciences, Pennsylvania State University, University Park, PA, United States

 
Female breasts undergo massive changes to transition from a rudimentary structure into a milk secreting organ and back to the pre-pregnant state. We studied the feasibility of imaging the phenotypic changes within mouse mammary glands using high field MRI. The results will assist in developing tools to utilize mouse models in better understanding breast development and disease in women.

 
2229.   Assessment of Intrahepatic Lipid Composition during Calorie Restriction and Exercise Intervention in Diet Induced Obese Rats by MRS
Venkatesh Gopalan1, Jadegoud Yaligar1, Swee Shean Lee1, Navin Michael2, and S Sendhil Velan1,2
1Laboratory of Molecular Imaging, Singapore Bioimaging Consortium, Singapore, Singapore, 2Singapore Institute for Clinical Sciences, Singapore, Singapore

 
Hepatic fat plays a major role in metabolic diseases including obesity, diabetes, and non-alcoholic fatty liver disease (NAFLD). In vivo magnetic resonance spectroscopy (MRS) permits non-invasive longitudinal assessment of fat fraction, saturated and unsaturated lipids. Interventions including exercise and calorie restriction play a major role in anti-obesity and also for recovery from NAFLD. In the current study we have estimated the changes in intrahepatic lipid content including, fat fraction, total unsaturated lipids (TUL), fraction of unsaturated lipid (fUL) and unsaturation index (UI) in five groups of high fat diet (HFD) fed obese rat model with exercise and calorie restriction interventions. Our preliminary results suggest significant reduction and modulation of intrahepatic lipids with exercise and calorie restriction.

 
2230.   Effect of weight loss on fatty acid composition of visceral and subcutaneous (deep and superficial) adipose tissues
Suresh Anand Sadananthan1,2, Navin Michael1, Eric Yin Hao Khoo3, Melvin K-S Leow1,4, ChinMeng Khoo3, Yung Seng Lee1,5, Peter Gluckman1, EShyong Tai3, and S. Sendhil Velan1,6
1Singapore Institute for Clinical Sciences, A*STAR, Singapore, Singapore, 2Department of Obstetrics & Gynaecology, National University of Singapore, Singapore, Singapore,3Department of Medicine, National University of Singapore, Singapore, 4Department of Endocrinology, Tan Tock Seng Hospital, Singapore, 5Department of Pediatrics, National University of Singapore, Singapore, 6Clinical Imaging Research Centre, A*STAR, Singapore

 
In addition to study of fat distribution in abdominal adipose tissues (visceral, deep and superficial subcutaneous), there has been an increasing interest in the investigation of fatty acid composition in these depots because of their association with insulin sensitivity. Studies have shown that the fatty acid makeup of the different fat compartments vary between each other. Weight loss intervention is known to alter this composition in adipose tissues, with studies showing decreased levels of monounsaturated fatty acids after intervention. In this study, we investigated the potential for non-invasively monitoring the changes in the fatty acid composition of adipose tissue triglycerides due to weight loss intervention using MRS.

 
2231.   Modulation of the abdominal visceral and subcutaneous adipose tissue by fat storage-inducing transmembrane (FIT) proteins - An Imaging Study
Jadegoud Yaligar1, Diego A Miranda2, Bhanu Prakash KN1, David Lawrence Silver2, and S Sendhil Velan1
1Laboratory of Molecular Imaging, Singapore Bioimaging Consortium, Singapore, Singapore, Singapore, 2Signature Research Program in Cardiovascular & Metabolic Diseases, Duke-NUS Graduate Medical School Singapore, Singapore, Singapore

 
Fat deposition in the body can be regulated by silencing the fat storage-inducing transmembrane (FIT) protein in in vivo animal models. In our current study we have evaluated the abdominal fat in both FIT2 adipose-specific knockout (AF2KO) and their littermate (LL) control mouse model using MRI technique. Volumes of SAT and VAT fat fractions were significantly (p < 0.05) higher in LL control compared to AF2KO mice. Both SAT and VAT fat contents of AF2KO mice were significantly (p < 0.05) lower than LL mice, indicating a vital role of FIT2 in lipid accumulation. Silencing the FIT2 protein has reduced the fat accumulation even in high fat diet fed conditions. Modulation (either down regulation or silencing) of these proteins by drugs in obesity and type 2 diabetic conditions might be helpful in preventing the fat accumulation in the body.

 
2232.   Serum Metabolic Signature in an animal model of binge eating by Nuclear Magnetic Resonance Spectroscopy
Valeria Righi1, Silvia Alboni2, Luisa Schenetti2, Carlo Cifani3, Nicoletta Brunello2, and Adele Mucci4
1Department for the Quality of Life Studies, University of Bologna, Rimini, RN, Italy, 2Department of Life Sciences, University of Modena and Reggio Emilia, Modena, MO, Italy,3School of Pharmacy, Pharmacology Unit, University of Camerino, Camerino, MC, Italy, 4Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, Modena, MO, Italy

 
Binge Eating (BE) episodes are characterized by uncontrollable, distressing eating of a large amount of highly palatable food (HPF). Considerable evidence suggests that BE may be caused by a unique interaction between dieting and stress. In our model BE for HPF is evoked in rats by the combination of cyclic food restrictions and stress. In order to investigate BE behavior in female rats, for the first time, we analyzed the metabolic profile obtained from biological fluids of rats exposed or not to cycles of food restriction and a stressful challenge through the High Resolution Nuclear Magnetic Resonance Spectroscopy.

 
2233.   Effect of High Fat/High Fructose Diet on Canine Model Using Quantitative Fat Water MRI
Myriam Diaz Martinez1,2, Aliya Diaz Gifford2,3, Philip E Williams4, Alan D Diaz Cherrington4, Malcolm J Avisom5, and E Brian Welch3,6
1Department of Radiology and Radiological Sciences, Vanderbilt University, School of Medicine, Nashville, TN, United States, 2Chemical and Physical Biology Program, Vanderbilt University Medical Center, Nashville, TN, United States, 3Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States,4Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, United States, 5Department of Pharmacology, Vanderbilt University, School of Medicine, Nashville, TN, United States, 6Department of Radiology and Radiological Sciences, Vanderbilt University, School of Medicine, Nasville, TN, United States

 
The purpose of this study was to detect organ-specific changes in fat-water signal over the course of high fat/high fructose diet consumption. The effect of the diet was evaluated exposing a canine animal model to the diet and measurements were acquired using the quantitative method of fat-water MRI (FWMRI), with interleaved multiecho pulse sequence. This technique is a promising new imaging modality for the research areas of obesity and metabolic diseases. Results indicate that liver and subcutaneous tissues fat fraction increased over the course of the study, consistent with the development of obesity comorbidities such as type 2 Diabetes Mellitus.

 
2234.   USPIO enhanced MRI in NAFLD; a feasibility and proof of concept study
Loek P. Smits1, Bram Coolen2, Wouter Nijhof1, Jurgen H. Runge2, Erik S. Stroes1, and Aart J. Nederveen2
1Department of Vascular Medicine, AMC, Amsterdam, Netherlands, 2Department of Radiology, AMC, Amsterdam, Netherlands

 
Differentiation between simple steatosis and steatohepatitis (NASH) is of clinical and prognostic importance, but no non-invasive diagnostic tests currently available are capable of this. Previous studies showed the promise of iron-oxide particle enhanced MRI as a diagnostic tool to identify patients with NASH. In the present study we present a protocol for ultrasmall particles of iron-oxide (USPIO) enhanced MRI, and demonstrate that patients with NASH have a decreased hepatic uptake of USPIOs. Future studies are needed to show whether USPIO-MRI indeed is capable of differentiation NASH from simple steatosis.

 
2235.   Combined Gadoxetic Acid and Gadofosveset Enhanced Liver MRI: A Feasibility and Parameter Optimization Study
Peter Bannas1,2, Utaroh Motosugi1, Diego Hernando1, Mahdi S Rahimi3, James H Holmes4, and Scott B Reeder1,5
1Department of Radiology, University of Wisconsin, Madison, Madison, WI, United States, 2Department of Radiology, University Medical Center Hamburg-Eppendorf, Hamburg, Hamburg, Germany, 3Department of Biomedical Engineering, University of Wisconsin, Madison, Madison, WI, United States, 4Global MR Applications and Workflow, GE Healthcare, Madison, WI, United States, 5Department of Medical Physics, University of Wisconsin, Madison, Madison, WI, United States

 
Gadoxetic acid enhanced hepatobiliary phase MRI is useful for detection of hypointense liver metastases. However, vessels and benign cavernous hemangiomas also appear hypointense on gadoxetic acid enhanced MRI and may be difficult to distinguish from one another. We hypothesized that use of an intravascular contrast agent, gadofosveset trisodium, in addition to gadoxetic acid, may address this issue. The purpose of this work was to demonstrate the feasibility of combined use of these two contrast agents and to optimize MR parameters. We concluded that combination of the two contrast agents is feasible and worth testing in a clinical setting.

 
2236.   MR based evaluation of subcutaneous, visceral and intermuscular adipose tissue as markers for metabolic disorders
Rama Jayasundar1, Somenath Ghatak1, Ankur Poddar2, Ariachery C Ammini3, and Ashok K Mukhopadhyaya4
1Department of NMR, All India Institute of Medical Sciences, New Delhi, Delhi, India, 2Department of Biotechnology, All India Institute of Medical Sciences, New Delhi, Delhi, India, 3Department of Endocrinology, All India Institute of Medical Sciences, New Delhi, Delhi, India, 4Department of Laboratory Medicine, All India Institute of Medical Sciences, New Delhi, Delhi, India

 
With increasing prevalence of metabolic disorders like diabetes, the importance of predictive markers is gaining attention. In this study, MRI based visceral and subcutaneous adipose tissue (SAT), and intermuscular adipose tissue (IMAT) as an index of metabolic health have been evaluated in Asian Indian population (n = 47), known to have high predisposition to type 2 diabetes. The results were also correlated with biochemical metabolic risk indices and other body composition analysis techniques like DEXA and BIA. SAT at L3 level with maximum correlations and also IMAT at midthigh could be predictive markers in identifying risk population for metabolic disorders.

 
2237.   Evaluation of impact factors in the regeneration process of hematomas in the subcutaneous fatty tissue
Kathrin Ogris1,2, Eva Hassler3, Andreas Petrovic1, Bernhard Neumayer1, Thomas Widek1, and Eva Scheurer1,2
1Ludwig Boltzmann Institute Clinical-Forensic Imaging, Graz, Styria, Austria, 2Department of Legal Medicine, Medical University of Graz, Styria, Austria, 3Department of Radiology, Medical University of Graz, Styria, Austria

 
While the detection of hemorrhage in clinical medicine is focused on organs and body cavities forensic imaging requires reliable analysis of hematomas in subcutaneous fatty tissue for the reconstruction of events. In 20 healthy volunteers autologous blood was injected into the subcutaneous tissue of the thigh and repetitive MRI scans of the artificial hematoma were performed. When analyzing the final data, by calculating the Michelson contrast and a morphological evaluation of the hematomas and the fatty tissue, we came across three major influence factors (hematoma shape, fatty tissue structure and hematoma regeneration) for the assessment of the age of bruises.

 
2238.   Coronal whole body diffusion imaging with 2D spatially selective excitation (FOCUS)
Maggie M Fung1, Lloyd Estkowski2, Dan Xu3, Suchandrima Banerjee2, Pauline Worters2, Gaohong Wu4, John Skinner4, and Ersin Bayram5
1Global MR Applications and Workflow, GE Healthcare, Jersey City, NJ, United States, 2Global MR Applications and Workflow, GE Healthcare, Menlo Park, CA, United States,3Global MR Applications and Workflow, GE Healthcare, Waukesha, WI, United States, 4MR Engineering, GE Healthcare, Waukesha, WI, United States, 5Global MR Applications and Workflow, GE Healthcare, Houston, TX, United States

 
Diffusion weighted whole body imaging is conventionally acquired axially to reduce image distortion due to B0 inhomogeneity in the SI direction. However, axial DWI acquisition requires longer scan time, as compared to coronal acquisition, and direct coronal DWI requires high acceleration factor to reduce distortion. We propose an alternative method for coronal diffusion imaging using 2D spatially selective excitation (FOCUS) that can reduce distortion at lower acceleration factors. We have shown that FOCUS imaging suffers much less distortion compared to conventional rectangular FOV imaging at the same acceleration factor and can be clinically viable for whole body diffusion imaging.

 
2239.   Continuously moving table whole-body diffusion weighted imaging using an adaptive gradient reversal technique
Yeji Han1, Chang Heun Oh1, and HyunWook Park1
1Department of Electrical Engineering, KAIST, Daejeon, Daejeon, Korea

 
Although whole-body diffusion-weighted imaging (wbDWI) is generally performed using the multistation approach, the continuously moving table (CMT) approach can be used as an alternative to generate images with more homogeneous temporal and spatial continuities. While STIR is an appropriate choice for fat and background signal suppression in 1.5T MRI systems, a more efficient fat-suppression technique is required for the CMT-wbDWI in 3T MRI. In this abstract, an adaptive gradient reversal technique is proposed for the CMT-wbDWI method, where the opposite polarities of slice selection gradients are used for 90° and 180° RF pulses with an RF pulse adaptation.

 
2240.   Whole-body diffusion-weighted MRI with apparent diffusion coefficient mapping for monitoring multiple myeloma
Shuo Li1, Huadan Xue2, Jian Li3, Haibo Zhang4, Zhaoyong Sun2, and Zhengyu Jin2
1department of radiology, Peking Union Medical College Hospital, Beijing, Beijing, China, 2department of radiology, Peking Union Medical College Hospital, Beijing, China,3department of hematology, Peking Union Medical College Hospital, Beijing, China, 4Peking Union Medical College Hospital, Beijing, China

 
Purpose: To analyses the diagnostic potential of DWIBS in the detection and discrimination of focal bone marrow lesions from multiple myeloma (MM). Methods: A prospective analysis including 25 MM patients. 12 newly diagnosed MM patients were divided in active group. 13 MM patients after therapy were divided in stationary group. The mean ADC value was evaluated in all foci lesions > 1 cm. Five regions of bone marrow were calculated. Results: The mean ADC value of active lesions (n=114) was (880.04¡À212.31)¦Ìm2/S, which is significantly lower than that of inactive lesions (n= 80) (1784.29¡À419.17)¦Ìm2/S. The mean ADC value of diffusely infiltrated marrow is (632.91¡À43.52)¦Ìm2/S, higher than those of stationary period bone marrow(286.18¡À25.17) ¦Ìm2/S and only focal myeloma bone marrow(420.25¡À31.11) ¦Ìm2/S. Coclusion: The ADC value allows differentiation between active and stationary myeloma lesions, normal bone marrow and tumors of myeloma.

 
2241.   Comparison of GRAPPA Acquisition Methods for Whole Body Diffusion Weighted Imaging
Sarah A Mason1, Matthew D Blackledge1, David J Collins1, Thorsten Feiweier2, Yiliang Thian1, Dow-Mu Koh1, and Martin O Leach1
1CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden Hospital, Sutton, Surrey, United Kingdom, 2Healthcare Sector, Siemens AG, Erlangen, Germany

 
We investigated how the technical differences between ss-EPI(R=2), FLASH(R=2) and FLASH(R=3) ACS acquisition methods visually manifest themselves in the context of WBDWI imaging. We analyzed: geometric distortion, SNR, overall image quality, and inter-station registration. FLASH(R=3) had the highest geometric fidelity, fewer image artifacts, and good station-station alignment. These advantages are offset by a lower SNR of ~17%: this may be partially responsible for the tendency of FLASH(R=2) ACS data to be rated higher than FLASH(R = 3) ACS data in terms of overall MIP quality. There was no situation in this study in which ss-EPI outperformed FLASH.

 
2242.   Simultaneous Model Estimation and Image Reconstruction (SMEIR) to improve Multi b-Value body Diffusion-Weighted imaging
Moti Freiman1, Onur Afacan1, Robert V Mulkern1, and Simon K Warfield1
1Radiology, Boston Children's Hospital/Harvard Medical School, Boston, MA, United States

 
Diffusion-weighted MRI images acquired with multiple b-values have the potential to improve diagnostic accuracy by increasing the conspicuity of lesions and inflammatory activity with background suppression. Unfortunately, the inherently low signal-to-noise ratio (SNR) of DW-MRI reduces enthusiasm for using these images for diagnostic purposes. Moreover, lengthy acquisition times limit our ability to improve the quality of multi b-value DW-MRI images by multiple excitations acquisition and signal averaging at each b-value. To offset these limitations, we propose the Simultaneous Model Estimation and Image Reconstruction (SMEIR) for DW-MRI, which substantially improves the quality of multi b-value DW-MRI images without increasing acquisition times.

 
2243.   Assessment of reproducibility of IVIM based perfusion fraction and diffusion coefficient in the pancreas
Oliver J. Gurney-Champion1, Martijn Froeling2, Remy Klaassen1, Jaap Stoker1, Geertjan van Tienhoven1, Hanneke W.M. van Laarhoven1, Arjan Bel1, and Aart J. Nederveen1
1Academic Medical Center, Amsterdam, Netherlands, 2University Medical Center Utrecht, Netherlands

 
The perfusion fraction, f, obtained from intravoxel incoherent imaging can potentially be used as biomarker to distinguish between pancreatic carcinomas and healthy tissue. Using an optimized imaging sequence, together with an in-house post-processing toolkit in eight healthy volunteers, we show a good reproducibility for f (RI=17%) and diffusion coefficient, D, (RI=13%). Averaging over all volunteers we found D=1.40±0.07x10-3 mm3/s, f=9.4±1.8 % and pseudo-diffusion coefficient D*=0.0871 mm3/s . We showed how the RI decreases for decreasing number of averages. Finally, for one patient, we could observe a difference in f between healthy and tumorous pancreas tissue.

 
2244.   Intravoxel Incoherent Motion MRI of the pancreatic adenocarcinomas: Characterization and Histopathological Correlations
Chao Ma1, Yanjun Li1, Luguang Chen1, Yang Wang2, Yong Zhang3, He Wang3, Shiyue Chen1, and Jianping Lu1
1Radiology, Changhai Hospital of Shanghai, Shanghai, Shanghai, China, 2Pathology, Changhai Hospital of Shanghai, Shanghai, Shanghai, China, 3MR group, GE healthcare, Shanghai, Shanghai, China

 
The purpose of the study was to identify prospectively potential associations between the DWI-derived IVIM parameters such as f (perfusion fraction), ADCfast (pseudo-diffusion coefficient), ADCslow (the tissue diffusivity) and these parameters with the commonly used DWI-derived ADCs of pancreatic adenocarcinoma and the tumor grade as well as other pathological features.

 
2245.   Comparison of FOCUS and Conventional DWI for Evaluation of Intra-pelvic Tumor
Motoyuki Katayama1, Takayuki Masui1, Kimihiko Sato1, Kei Tsukamoto1, Kenichi Mizuki1, Mitsuharu Miyoshi2, and Nami Matsunaga2
1Radiology, Seirei Hamamatsu General Hospital, Hamamatsu, Shizuoka, Japan, 2GE Healthcare Japan, Hino, Tokyo, Japan

 
We compared the performance of FOCUS DWI for evaluation of intra-pelvic tumor with that of conventional DWI. 14 patients with pelvic tumor who underwent 3.0T MRI were included in this study. Correlation coefficient of ADC with FOCUS and conventional DWI was 0.79. On qualitative analysis, conspicuity and structural visualization of tumor in FOCUS DWI was superior to that of Conventional DWI. FOCUS DWI is useful for evaluation of intra-pelvic tumor.

 
2246.   Robust Diffusion-Weighted Single-Shot MRI Can Resolve Major Mice Placental Compartments
Eddy Solomon1, Reut Avni2, Peter Bendel3, Lucio Frydman1, and Michal Neeman2
1Chemical Physics, Weizmann Institute of Science, Rehovot, Israel, 2Biological Regulation, Weizmann Institute of Science, Rehovot, Israel, 3Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel

 
Novel diffusion-based MRI methodologies relying on SPatio-temporal ENcoding (SPEN) were developed, and used to uncover in-vivo aspects about the diffusion of fluids in mouse placenta. Macromolecular contrast agents were used to distinguish the ADC’s of maternal blood capillaries, fetal blood capillaries and trophblast giant cells. Significantly, different diffusion and perfusion properties were thus noticed, spanning nearly two orders of magnitude. This yields a new multiparametric view of the placenta whereby mainly free diffusion occurs in the maternal blood, a strongly forced perfusion is observed in the fetal microcapillaries, and moderate fluid exchanges characterizes the trophoblasts lining the maternal blood pool.

 
2247.   Hepatic parenchymal visibility and ADC quantification on diffusion-weighted MRI at 3T: influence of age, gender and iron content in normal subjects
Thierry Metens1, Kellen Fanstone-Ferraresi1, Alessandra Farchione1, Maria Antonietta Bali1, Julie Absil1, Christophe Moreno1, and Celso Matos1
1IRM Hôpital Erasme, Université Libre de Bruxelles, Bruxelles, Belgium

 
In diffusion-weighted images the normal liver signal intensity is associated with age and gender in healthy subjects and is correlated with T2* and serum ferritin. ADC values are influenced by T2*values

 
2248.   Intravoxel incoherent motion analysis of abdominal organs: computation of base values in a large cohort of B57Bl/10 mice
Christian Eberhardt1, Moritz Wurnig1, Andrea Vuck2, Mickael Lesurtel2, and Andreas Boss1
1Department of Diagnostic and Interventional Radiology, University Hospital Zürich, Zürich, Switzerland, 2Department of Visceral and Transplant Surgery Research, University Hospital Zürich, Zürich, Switzerland

 
Intravoxel incoherent motion MRI (IVIM-MRI) has lately been increasingly used in clinical studies on a variety of diseases. As animal models are widely used in translational research, the objective of this study was to establish tissue diffusion and perfusion parameters of murine abdominal organs serving as reference for the discrimination of tissue pathologies in animal disease models. Here, the pseudodiffusivity (Dp), tissue diffusivity (Dt) and the perfusion fraction (fp) of the liver, renal cortex, renal medulla, spleen and small bowel were characterized by IVIM- MRI on a large cohort of C57Bl/10 mice (n=50).

 
2249.   Diffusion weighted imaging of the kidneys in freely breathing infants using multidirectional scanning
Yvonne Simrén1, Eira Stokland1, Sverker Hansson2, P-A Svensson1, and Kerstin Lagerstrand3
1Department of Pediatric Radiology, Sahlgrenska University Hospital, Gothenburg, Sweden, 2Department of Pediatrics, Sahlgrenska University Hospital, Gothenburg, Sweden,3MR centre, Sahlgrenska University Hospital, Gothenburg, Sweden

 
Problem Free breathing renal diffusion weighted MR imaging (DWI) is sensitiv to motion artefacts. Methods Thirteen infants were scanned during free breathing without sedation. Signal to noise ratio (SNR) was compared between conventional DWI, tetrahedral DWI and diffusion tensor imaging (DTI). Results The decrease in SNR was significantly lower for DTI (0.36±0.11) than for cDWI (0.52± 0.08; p<0.05) and tDWI (0.54±0.1; p<0.05) indicating higher image quality. There was no significant difference in SNR for tDWI compared to cDWI (p=0.08). Conclusion The image quality in DTI appears to be superior to conventional and tetrahedral DWI in free breathing renal imaging.

 
2250.   Improved confidence in IVIM diffusion metrics from ‘post-navigator’ registration of individual coronal signal average images in abdominal DW-MRI
Neil P Jerome1, Matthew R Orton1, James d'Arcy1, Dow-Mu Koh2, David J Collins1, and Martin O Leach1
1CR-UK and EPSRC Cancer Imaging Centre, The Institute of Cancer Research, Sutton, Surrey, United Kingdom, 2Department of Radiology, Royal Marsden Hospital, Sutton, Surrey, United Kingdom

 
Blurring, commonly observed in abdominal DWI, arises from respiratory motion between successive acquisitions of signal averages and diffusion gradient directions. Storing coronal DWI images separately allows post-processing alignment by voxel-wise shifting, correcting for a large amount of (predominantly in-plane) respiratory motion. In a volunteer cohort (n=10), residual sum-of-squares as a proxy for uncertainty of IVIM model parameters decreased for renal ROIs following shifting, and further decreased with the exclusion of apparent outlier images. Voxel-wise shifting provides improved confidence in local DWI parameters along with sharper tissue boundaries within images and parameter maps, using a simple and computationally inexpensive method.

 
2251.   Study of chronological effects of iodinated contrast medium on intrarenal water molecular diffusion by diffusion-weighted MR imaging
Jia Liu1, Kai Zhao1, and Xiaoying Wang1
1Peking University First Hospital, Beijing, Beijing, China

 
Usage of iodinated contrast medium during radiological procedure may cause contrast induced nephropathy (CIN). Unfortunately the pathogenesis of CIN is currently unclear, and maybe characteristics of contrast medium affect the development of CIN. Our study demonstrated that it is feasible to monitor the time course effects on renal function after different iodinated contrast medium administration in rabbit models using diffusion-weighted MR imaging. Iopamidol-370 causes more deterioration on intrarenal water transport function than iodixanol-320. This may be helpful to understand the pathogenesis associated with CIN. We introduce a clinical clue to choose better contrast medium to prevent the incidence of CIN.

 
2252.   Free-breathing abdominal IVIM imaging
Yu-Chen TSAI1 and Teng-Yi Huang1
1Department of Electrical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan

 
This study aims to apply intravoxel incoherent motion (IVIM) method to free-breathing abdomial imaging. Previous studies acquired diffusion-weighted imaging with prospective respiratory gating multiple averages, and 10 b values. We proposed to acquire images with 91 b values and no averages, and without respiratory-gating. We used a retrospective selection algorithm based on rejecting indexes calculated from fitting residuals. The spatial variations obtained using the proposed method was comparable to that obtained using the protocol presented in the previous study. We concluded that the proposed method is a useful alternative to the respiratory-gated acquisition methods and can be a practical method for abdominal IVIM imaging.

 
2253.   The effect of ROI size and analysis technique on IVIM parameters in the liver
Alexander D Cohen1, Mark D Hohenwalter2, and Kathleen M Schmainda2
1Biophysics, Medical College of Wisconsin, Milwaukee, WI, United States, 2Radiology, Medical College of Wisconsin, Milwaukee, WI, United States

 
The intravoxel incoherent motion (IVIM) analysis technique has been used to model diffusion in the liver. Perfusion-related components can be extracted from the DWI signal through the collection of multiple b-values. Once the data is collected, there are a number of different ways to analyze that data. IVIM parameter values were compared with different ROIs and analysis techniques in order to determine which combination provided the best separation between normal and cirrhotic livers. Differences were found for different ROI sizes. Larger ROIs provided better separation between normal and cirrhotic livers, and voxelwise extraction techniques were less variable than ROI techniques.

 
2254.   The effect of very low b-values on the IVIM-derived pseudodiffusion parameter in the liver
Alexander D Cohen1, Moira C Schieke2, Mark D Hohenwalter2, and Kathleen M Schmainda2
1Biophysics, Medical College of Wisconsin, Milwaukee, WI, United States, 2Radiology, Medical College of Wisconsin, Milwaukee, WI, United States

 
The intravoxel incoherent motion (IVIM) analysis technique has been used to model diffusion in the liver. This model allows for the extraction of perfusion-related components from the DWI signal. When b<50 s/mm2 are not included in the b-value distribution, the pseudodiffusion parameter has tended to be lower than when b<50 s/mm2 are included. This study used simulations to examine the effect of very low b-values on the pseudodiffusion parameter. Pseudodiffusion tended to be underestimated when very low b-values were excluded from the distribution. It is recommended to include at least two very low b-values when performing IVIM studies in the liver.

 
2255.   Reduction of cardiac motion-related effects on liver diffusion imaging
Diego Hernando1, Utaroh Motosugi1,2, Peter Bannas1,3, Samir D. Sharma1, and Scott B. Reeder1,4
1Radiology, University of Wisconsin-Madison, Madison, WI, United States, 2Radiology, University of Yamanashi, Yamanashi, Japan, 3Radiology, University Hospital Hamburg-Eppendorf, Hamburg, Germany, 4Medicine, University of Wisconsin-Madison, Madison, WI, United States

 
Cardiac motion-related effects are severe in liver diffusion MRI, where they introduce signal voids in diffusion-weighted images (particularly in the left liver lobe) and result in errors and high variability in ADC measurements. This variability has precluded the widespread application of quantitative liver diffusion MRI. In this work, we characterize cardiac motion effects on liver diffusion imaging, and assess simple correction techniques to reduce variability in ADC maps by taking maximum intensity over multiple signal acquisitions (ADCMIP), in which we hypothesized we could exclude signals affected by cardiac motion. The ADCMIP was less affected by cardiac-motion than conventional ADC maps.

 
2256.   Postmortal DWI of the Liver in comparison with in vivo data
Jin Yamamura1, Murat Karul1, Sarah Keller1, Tony Manfred Schmidt1, Axel Heinemann2, Gerhard Adam1, and Roland Fischer3,4
1Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Hamburg, Hamburg, Germany, 2Department for Forensic Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Hamburg, Germany, 3Department for Biochemistry, University Medical Center Hamburg-Eppendorf, Hamburg, Hamburg, Germany,4Paediatric Haematology, Children's Hospital Oakland Research Institute, Oakland, CA, United States

 
So far, there are few DWI investigations of corpses. The most recent study using DWI (including ADC-Mapping) in post mortem brain seemed to be useful and especially promising in forensic medicine. The purpose of this study was to assess both the changes in water diffusion quantified by diffusion-weighted MR imaging in post mortem liver tissue and to examine the development of the apparent diffusion coefficient (ADC) in the liver after death in comparison to ADC values in vivo tissue.

 
2257.   Semi-Continuous Regularized Multi-Exponential Fitting Model for Diffusion Weighted Imaging of the Liver
Burkhard Mädler1,2 and Jürgen Gieseke2,3
1Neurosurgery, University of Freiburg, Freiburg, Germany, 2Philips Healthcare, Hamburg, Germany, 3Radiology, University of Bonn, Bonn, Germany

 
Several studies have utilized IVIM for various clinical applications in the abdomen. We tested performance and validity of a novel semi-continuous multi-exponential PFG-diffusion signal analysis for the detection and quantification of vascular perfusion in the liver with a patient friendly free-breathing approach. Classical chi-squared multi-exponential fitting algorithms are susceptible to fail without sufficient SNR. We show that regularized NNLS-techniques together with high number of b-value DWI-acqusition have better performance on the estimates of IVIM parameters and might encourage new attempts of clinical IVIM-based methods in general.

 
2258.   Differentiation of Malignant from Benign Focal Splenic Lesions: Added Value of Diffusion-Weighted MR Imaging
Jiyoung Hwang1, Kyung Mi Jang2, Seong Hyun Kim2, and Mi Hee Lee3
1Department of Radiology, Soonchunhyang University Seoul Hospital, Seoul, Seoul, Korea, 2Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Seoul, Korea, 3Radiology, Samsung Medical Center, Sungkyunkwan University, Seoul, Seoul, Korea

 
Purpose: To evaluate the added value of diffusion-weighted (DW) MR imaging for differentiating between malignant and benign focal splenic lesions. Methods: This study included 53 patients with 11 malignant and 42 benign splenic lesions and who underwent gadoxetic acid-enhanced and DW MR imaging. Qualitative and quantitative analyses were conducted for splenic lesions. Results: All malignant lesions showed a hypovascular progressive enhancement pattern, while hypervascular enhancement patterns were only demonstrated in benign lesions (20, 47.6%) (P<0.05). The mean ADC of malignant lesions was lower than that of benign lesions (P< .001). The addition of DW images to conventional MR images showed a significant improvement for predicting malignant splenic lesions (P < 0.001) Conclusion: The addition of DW imaging to conventional MR imaging improves differentiation of malignant from benign splenic lesions.

 
2259.   Interethnic differences in fatty acid composition of deep subcutaneous abdominal adipose tissue
Suresh Anand Sadananthan1,2, Navin Michael1, Melvin K-S Leow1,3, ChinMeng Khoo4, Eric Yin Hao Khoo4, Yung Seng Lee1,5, Peter Gluckman1, EShyong Tai4, and S. Sendhil Velan1,6
1Singapore Institute for Clinical Sciences, A*STAR, Singapore, Singapore, 2Department of Obstetrics & Gynaecology, National University of Singapore, Singapore, Singapore,3Department of Endocrinology, Tan Tock Seng Hospital, Singapore, 4Department of Medicine, National University of Singapore, Singapore, 5Department of Pediatrics, National University of Singapore, Singapore, 6Clinical Imaging Research Centre, A*STAR, Singapore

 
The study of fat distribution is important to understand the pathophysiology of obesity-related disorders, diabetes mellitus and cardiovascular diseases. Several studies have suggested that the fat distribution is different across different ethnic groups. In addition to the analysis of fat distribution, the investigation of the fatty acid composition is also important because of their varying metabolic properties and association with insulin sensitivity. Differences in the fatty acid composition induced by diet or ethnicity could potentially make some groups more susceptible to metabolic disorders. In this study, we investigated the fatty acid composition in the abdominal deep subcutaneous adipose tissue of three ethnicities (Chinese, Malays and Indians) non-invasively using MRS approaches.

 
2260.   Hepatic Cholesterol Ester Accumulation in Lysosomal Acid Lipase Deficiency: Non-invasive Identification and Treatment Monitoring by Magnetic Resonance
Peter E Thelwall1, Fiona E Smith1, Mark Leavitt2, David Canty2, Wei Hu2, Kieren G Hollingsworth1, Christian Thoma3, Michael Trenell3, Roy Taylor1, Joseph V Rutkowski2, Andrew M Blamire1, and Anthony G Quinn2
1Newcastle Magnetic Resonance Centre, Newcastle University, Newcastle upon Tyne, Tyne and Wear, United Kingdom, 2Synageva Biopharm Corp, Lexington, MA, United States, 3Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, Tyne and Wear, United Kingdom

 
Cholesterol Ester Storage Disease (CESD) is caused by accumulation of cholesterol esters due to mutation in the gene encoding the enzyme Lysosomal Acid Lipase. We have demonstrated that hepatic 1H spectroscopy can be used to detect and quantify elevated hepatic cholesterol ester content. We performed preclinical studies on a rat model of CESD to demonstrate the ability of 1H MRS to quantify the effects of a novel enzyme replacement therapy. Furthermore, we translated our methods to human studies and demonstrated that elevated hepatic cholesterol ester content can be observed in patients with CESD.

 
2261.   Diastolic Dysfunction Is Temporally Dissociated from Myocardial Steatosis
Michael D Nelson1, Laura Smith1, Edward W Szczepaniak1, Ruchi Mathur1, Richard N Bergman1, and Lidia S Szczepaniak1
1Cedars-Sinai Medical Center, Los Angeles, California, United States

 
The risk for heart failure in obesity and diabetes is greater than can be accounted for by traditional factors of hypertension and coronary artery disease. Altered substrate metabolism may contribute to dysfunction of diabetic heart. In obesity and diabetes contribution of glucose oxidation to cardiac energetics is sub-normal with enhanced reliance on fatty acid metabolism. Most work in cardiac metabolism has been performed in rodent models. We present results from a study in which we altered cardiac metabolism by 48 hours fasting in humans. Cardiac metabolism was assessed by myocardial triglyceride content and diastolic function assessed by myocardial tissue tagging.

 
2262.   A low carbohydrate and high fat diet causes excessive myocardial lipid content.
Åsa Carlsson1,2, Maja Sohlin1,2, Sofi Holmquist2, Eva Forsell-Aronsson2, and Maria Ljungberg1
1Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, VGR, Sweden, 2Radiation Physics, Gothenburg University, Gothenburg, VGR, Sweden

 
During last years a diet with low carbohydrate and high fat content (LCHF) has become very popular in Sweden. There is, however, very little knowledge about the internal and long term effects of this kind of diet. In this study, cardiac MR spectroscopy is used to measure the myocardial lipid content in dieting and non-dieting volunteers. For both groups the myocardial lipid content was dependent on body mass index (BMI) and waist to hip ratio (WHR) alone. The group on diet showed excessive myocardial lipid content compared to the non-dieting group.

 
2263.   Postprandial ectopic lipid storage observed after a single meal: no influence of additional protein content
Lucas Lindeboom1,2, Christine Nabuurs1,3, Matthijs Hesselink3, Joachim Wildberger1, Vera Schrauwen-Hinderling1,2, and Patrick Schrauwen2
1Dept. of Radiology, MUMC+, Maastricht, Netherlands, 2Dept. of Human Biology, MUMC+, Maastricht, Netherlands, 3Dept. of Human Movement Sciences, MUMC+, Maastricht, Netherlands

 
We demonstrate that the postprandial storage of dietary fat, after a single high fat breakfast, can be measured with 1H-MRS. Nine lean healthy subjects were included in this study and intrahepactic and intramyocellular lipids were measured 3h and 5h after a single breakfast. The addition of protein to the diet, did not change the deposition of lipids.

 
2264.   In-vivo 1H MRS Shows Increased Liver Choline Levels in Hepatitis C Viral Infection
Nigel Paul Davies1,2, Robert Flintham3, Reina Lim4, and Jeremy W Tomlinson4
1Imaging & Medical Physics, University Hospitals Birmingham NHS Foundation Trust, Birmingham, West Midlands, United Kingdom, 2School of Cancer Sciences, University of Birmingham, Birmingham, West Midlands, United Kingdom, 3Imaging & Medical Physics, University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom,4University of Birmingham, Birmingham, United Kingdom

 
Hepatitis C virus (HCV) is a RNA virus with diverse genotypes and a broad spectrum of clinical outcome. Non-invasive methods for assessing disease severity and predicting treatment response are sought. In-vivo 1H MRS at multiple TE with correction for T2 decay has been used to investigate liver fat and total choline (tCho) levels in treatment-naïve HCV patients with early-stage liver disease compared with healthy controls. No significant differences in lipid levels were found. tCho was significantly higher in the HCV group compared with the controls. Potential changes in liver choline levels in HCV after a novel drug treatment will be investigated.

 
2265.   31P MRSI of the healthy liver at 3T and 7T with AMESING-boosted SNR
Jurgen H. Runge1, Wybe J.M. van der Kemp2, Dennis W.J. Klomp2, Aart J. Nederveen1, and Jaap Stoker1
1Radiology, Academic Medical Center, Amsterdam, Netherlands, 2Radiology, University Medical Center Utrecht, Utrecht, Netherlands

 
Patients with diffuse hepatic disease (e.g. viral hepatitis and NASH) may present with liver fibrosis or inflammation. Preliminary studies indicate that 31P-MRS may play a role in the non-invasive determination of liver inflammation by mapping NADPH concentration. We compared 2D MRSI at 3T with a SNR optimized 7T set-up and implemented the adiabatic multi-echo spectroscopic imaging sequence (AMESING) of the liver at 7T for further SNR gain. SNR increased by 1.3 to 3.1 between 3T and 7T while AMESING further boosted SNR by 1.2 to 1.6, showing its potential for the quantitative mapping of metabolite concentrations throughout the liver.

 
2266.   Liver biopsy, MRS and MRI fat fraction quantification in patients presenting fat and iron overload
Elise Bannier1, Amandine Coum2,3, Anne Boulic4, Giulio Gambarota2,3, and Yves Gandon4
1Unité VISAGES U746 INSERM-INRIA, IRISA UMR CNRS 6074, University of Rennes, Rennes, France, 2INSERM, UMR 1099, Rennes, France, 3Université de Rennes 1, LTSI, Rennes, France, 4Radiology Department, University Hospital of Rennes, Rennes, France

 
The purpose of the present study was to assess the ability of MR spectroscopy to quantify hepatic liver fat overload in the presence of low to moderate iron overload and compare the results with multi gradient echo MR imaging and percutaneous liver biopsy. Multi-spectral fat composition and quantification of saturated and unsaturated fatty acid ratios were also investigated. Fat fraction measurements obtained using MR spectroscopy, imaging and biopsy were well correlated. While MRI allows imaging of the whole liver, MR spectroscopy enables quantification of saturated and unsaturated fatty acid ratios

 
2267.   Comparison of T1, T2 and PDFF measured by 1H MR spectroscopy with histologic fibrosis stage.
Gavin Hamilton1, Michael S Middleton1, Tanya Wolfson2, Anthony C Gamst2, Jonathan C Hooker1, William M Haufe1, Brandon D Ang3, Rohit Loomba3, and Claude B Sirlin1
1Department of Radiology, UC San Diego, San Diego, California, United States, 2Computational and Applied Statistics Laboratory, SDSC, UC San Diego, San Diego, California, United States, 3Department of Medicine, UC San Diego, San Diego, California, United States

 
We developed a rapid multi-TR, multi-TE 1H MRS sequence for in vivo hepatic fat quantification and characterization that acquires 32 single-average spectra in a single breath-hold. Spectra were acquired without contrast at 3 Tesla in 55 adult subjects who also were undergoing a clinical liver biopsy. T1 and T2 of liver fat and water, and liver proton density fat fraction (PDFF) were measured and compared with histologic fibrosis stage. There were significant differences in water T2 with fibrosis, with higher values being associated with advanced fibrosis.

 
2268.   Eddy current correction in diffusion-weighted STEAM MRS in the presence of water and fat peaks
Stefan Ruschke1, Thomas Baum1, Hendrik Kooijman2, Marcus Settles1, Axel Haase3, Ernst J. Rummeny1, and Dimitrios C. Karampinos1
1Department of Diagnostic and Interventional Radiology, Technische Universität München, Munich, Germany, 2Philips Healthcare, Hamburg, Germany, 3Zentralinstitut für Medizintechnik, Technische Universität München, Garching, Germany

 
Eddy current effects can distort peak line shapes in DW-MRS, inducing asymmetric peaks and causing bias in the peak area quantification. Previous approaches require a reference signal to correct for eddy current effects. However, finding a reference signal is not always feasible in the presence of water and fat peaks. In the present work, an approach acquiring spectra with opposite diffusion gradient polarities and using an appropriate signal combination routine is proposed to correct for eddy current effects. Examples from the application of the proposed approach are shown in bone marrow and skeletal muscle, where both water and fat peaks are present.

 
2269.   Multiband-accelerated diffusion-weighted MR imaging of the abdominal organs: Initial experiences
Petros Martirosian1, Michael Erb2, Susanne Will1, Fritz Schick1, Sergios Gatidis3, Holger Schmidt3,4, Nina F Schwenzer1,3, and Christina Schraml1,3
1Section on Experimental Radiology, University of Tübingen, Tübingen, Germany, 2Department of Biomedical Magnetic Resonance, University of Tübingen, Tübingen, Germany,3Department of Diagnostic and Interventional Radiology, University of Tübingen, Tübingen, Germany, 4Department of Preclinical Imaging and Radiopharmacy, University of Tübingen, Tübingen, Germany

 
Diffusion-weighted imaging (DWI) of abdominal organs can require considerable measurement time, especially if respiratory triggering is performed. Here we present an approach to reduce the scan time of abdominal DWI by multiband-accelerated technique utilizing simultaneous radiofrequency excitation and acquisition of multiple slices. Our results reveal that a reduction of measuring time at least by 50 % is achievable without substantial compromising image quality using respiratory triggering. Multiband-accelerated technique seems to be a promising approach to reduce acquisition time in abdominal DWI applications for clinical routine.

 
2270.   Evaluation of a selective homonuclear multiple quantum coherence transfer CSI (SelMQC-CSI) sequence for lactate measurement in abdominal tumours
Lisa M Harris1, Nina Tunariu1, Nandita M deSouza1, Sharon Giles1, Veronica Morgan1, Alison MacDonald1, Martin O Leach1, and Geoffrey S Payne1
1CRUK and EPSRC Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden Hospital, Sutton, Surrey, United Kingdom

 
Lactate is an important metabolite in the assessment of malignant tissue detectable by magnetic resonance spectroscopy. It is often difficult to clinically detect the lactate methyl resonance, as the peak at 1.3 ppm is frequently obscured by intense lipid resonances. In this study we have successfully evaluated a selective homonuclear multiple quantum coherence transfer CSI (SelMQC-CSI) sequence in a small test group of patients with abdominal lesions. It was possible to detect and measure lactate in three patients (mean ± sd = 16.5 ± 1.7 mM, not corrected for T1 or T2, CRLB < 1.4) with abdominal lesions at 1.5T.

 
2271.   Drug Dissolution: Investigation of Different Fluor Containing Substances using 19F-MRI
Janet Friedrich1, Julia Schröder1, Sarah Kindgen2, Stefan Fischer1, Mark Schuppert1, Karsten Gogoll2, Peter Langguth2, and Laura Maria Schreiber1
1Department of Radiology, Johannes Gutenberg University Medical Center, Mainz, Germany, 2Institute of Pharmaceutical Technology and Biopharmacy, Johannes Gutenberg University, Mainz, Germany

 
The aim of the present work was the evaluation of different fluor containing substances in reference to their MR properties (relaxation times, signal intensity, spectra) and their potential usage in further investigations of drug dissolution processes. Perfluoro-15-crown-5-ether (PFCE), toothpaste jelly and two fluorinated alkanes were investigated. From MR side PFCE and SFA2 turned out to be the most attractive substances among the investigated compounds. However, the advantageous chemical properties assigned SFA2 as the most promising compound. Thus, a first tablet loaded with SFA2 was prepared and imaged.

 
2272.   Delayed hepatic signal recovery on ferucarbotran-enhanced magnetic resonance images in a rat model with regional liver irradiation
Toshihiro Furuta1,2, Masayuki Yamaguchi1, Ryutaro Nakagami1,3, Masaaki Akahane4, Manabu Minami5, Kuni Ohtomo4, and Hirofumi Fujii1
1Division of Functional Imaging, Research Center for Innovative Oncology, National Cancer Center Hospital East, Kashiwa, Chiba, Japan, 2Department of Radiology, Research Hospital, The Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo, Japan, 3Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan, 4Department of Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan, 5Department of Radiology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan

 
To investigate whether hepatic MR signal recovery in SPIO-enhanced MR imaging could be a marker for early diagnosis of irradiated areas, we investigated hepatic MR signal changes after X-irradiation to previously SPIO-accumulated rat livers and examined the relationship between hepatic MR signal and iron deposits. Sequential T2*-weighted MR images demonstrated signal recovery delay only in irradiated liver areas within 4 days. It seems that the signal recovery delay was due to SPIO-derived iron deposition because hepatic signal intensity negatively correlated with hepatic iron deposits. Hepatic signal recovery could be a novel diagnostic marker for the delineation of irradiated areas.

 
2273.   Hyperpolarized pyruvate allows early detection of lactate in real-time metabolism of acute liver failure rats
Laia Chavarria1,2, Jordi Romero-Giménez1,2, Eva Monteagudo3, Juan Córdoba1,2, and Silvia Lope-Piedrafita3,4
1Liver Unit, Hospital Vall Hebron, Barcelona, Barcelona, Spain, 2Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Barcelona, Spain, 3Servei de RMN, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain, 4Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Barcelona, Spain

 
Intracranial hypertension is a severe complication of acute liver failure (ALF) secondary to brain edema. The pathogenesis of cerebral edema in ALF is not clear but it is known that energy metabolism alterations are involved where a genesis of lactate seems to have an important role. We have studied the dynamic synthesis of brain metabolites using hyperpolarized 1-13C pyruvate in a rat model of ALF. We have found that ALF rats have a significant increase in the lactate/pyruvate ratio as compared to Control rats. Also, the production rate of lactate and alanine was higher in ALF rats.

 
2274.   Contrast-Enhanced Magnetic Resonance Lymphangiography of the Upper Limbs in Breast Cancer Related Lymphoedema: An Exploratory Study.
Marco Borri1, Maria A. Schmidt2, Kristiana D. Gordon2,3, Julie Hughes2, Erica D. Scurr2, Dow-Mu Koh2, Peter S. Mortimer2,3, and Martin O. Leach2
1CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden, Sutton, Surrey, United Kingdom, 2CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden, Surrey, United Kingdom, 3Department of Medicine, St George's University of London, London, United Kingdom

 
Breast cancer-related lymphoedema remains one of the most common and distressing morbidities in breast cancer survivors treated with surgery. In this work we have extended the use of Contrast-Enhanced MR Lymphangiography to upper limbs and produced high resolution MR images of lymphatic vessels at 1.5T. We propose a new quantitative protocol, which employs an intradermal injection with lower concentration of contrast agent and prevents T2*-related signal loss, allowing correct modelling of contrast agent uptake and minimizing venous enhancement. This protocol appears suitable for quantitative studies, and enables both structural and functional evaluation of the lymphatic system within the same examination.

 
 

TRADITIONAL POSTER SESSION ○ BODY
Pulmonary MRI/ GI

 
Wednesday 14 May 2014
Traditional Poster Hall  10:00 - 12:00

2275.   Reproducibility and Diffusion Direction Dependence of Helium-3 Lung Morphometry
James D Quirk1, Yulin V Chang1, and Dmitriy A Yablonskiy1
1Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, United States

 
Lung morphometry with hyperpolarized helium-3 MRI is a highly sensitive technique for the non-invasive measurement of alveolar microstructural parameters. Herein, we establish the reproducibility and diffusion direction dependence of this technique in five healthy subjects. The values of all lung morphometry parameters (including acinar duct radius, alveolar depth, and mean chord length) were highly reproducible over the short and long-term and did not depend upon the direction of the applied diffusion gradient. Together, this provides confidence for the use of helium-3 lung morphometry for longitudinal studies and clinical trials.

 
2276.   Early Detection Of Smoking-Induced Pulmonary Alterations Using Hyperpolarized 3He MRI Derived Alveolar Partial Pressure of Oxygen
Hooman Hamedani1, Stephen J. Kadlecek1, Masaru Ishii2, Yi Xin1, Hoora Shaghaghi1, Biao Han1, Sarmad Siddiqui1, Sarah Zarrin3, Milton Rossman1, and Rahim R. Rizi1
1University of Pennsylvania, Philadelphia, PA, United States, 2Johns Hopkins University, Merryland, United States, 3University of Pennsylvania, PA, United States

 
While hyperpolarized (HP) gas MRI has been used to estimate alveolar oxygen tension (pAO2) [1], it has not been systematically compared to Gold standard to assess its potential for monitoring disease progression and response to new therapies. In this work, we compare imaged pAO2 to data produced via pulmonary function test, six-minute walk test, and St.-George Questionnaire.

 
2277.   In vivo MRI effectively monitors onset and progression of bleomycin-induced lung fibrosis in free-breathing mice
Greetje Vande Velde1, Tom Dresselaers2, Ellen De Langhe2,3, Jennifer Poelmans2, Rik Lories2,3, and Uwe Himmelreich2
1Imaging & Pathology, KU Leuven, Leuven, Flanders, Belgium, 2KU Leuven, Flanders, Belgium, 3UZ Leuven, Flanders, Belgium

 
Longitudinal MRI may enable sensitive assessment of lung fibrosis onset and progression in free-breathing mice, without radiotoxicity concerns or invasive endpoint measurements. We compared the potential of UTE and self-gated MRI with a conventional respiratory triggered pulse sequence to monitor lung fibrosis onset and progression in the bleomycin-induced pulmonary fibrosis mouse model. All three MRI protocols could sensitively visualize and quantify lung disease onset and progression in individual mice. In vivo MRI results correlated strongly with µCT and histological readouts for lung fibrosis. MRI is therefore a safe and non-invasive alternative to invasive methods for screening novel anti-fibrotic therapies.

 
2278.   Imaging Hyperpolarized 129Xe Uptake in Pulmonary Barrier and Red Blood Cells Using a 3D Radial 1-Point Dixon Approach: Results in Healthy Volunteers and Subjects with Pulmonary Fibrosis
Suryanarayanan S Kaushik1,2, Scott H Robertson2,3, Matthew S Freeman2,3, Craig Rackley4, Zackary I Cleveland2,5, Mu He2, Rohan S Virgincar1,2, Kevin T Kelly6, William M Foster4, Justus E Roos5, H Page McAdams5, and Bastiaan Driehuys2,5
1Biomedical Engineering, Duke University, Durham, NC, United States, 2Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States,3Graduate Program in Medical Physics, Duke University, Durham, NC, United States, 4Pulmonary, Allergy and Critical Care Medicine, Duke University Medical Center, Durham, NC, United States, 5Radiology, Duke University Medical Center, Durham, NC, United States, 6Radiation Oncology, Duke University Medical Center, Durham, NC, United States

 
MRI of dissolved-phase hyperpolarized 129Xe has emerged as a non-invasive probe of gas-exchange in the lung. Through dissolved-phase spectroscopy resolving the 197 ppm barrier tissue and 217 ppm red blood cells (RBC) resonances, we have shown that subjects with pulmonary fibrosis (PF) display a dramatically reduced RBC signal, indicative of diffusion limitation. Here, we show the initial results in creating separate images of 129Xe in the barrier tissue and the RBCs, using a 3D 1-pt Dixon approach. Preliminary application of the technique to PF now reveals diffusion impairment regionally.

 
2279.   Establishing Biomarkers of Gas-Transfer Using Hyperpolarized 129Xe Dissolved-Phase Spectroscopy in Healthy Volunteers and Subjects with Pulmonary Fibrosis
Suryanarayanan S Kaushik1,2, Matthew S Freeman2,3, Craig Rackley4, Jane Stiles4, William M Foster4, Justus E Roos5, H Page McAdams5, and Bastiaan Driehuys2,5
1Biomedical Engineering, Duke University, Durham, NC, United States, 2Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States,3Graduate Program in Medical Physics, Duke University, Durham, NC, United States, 4Pulmonary, Allergy and Critical Care Medicine, Duke University Medical Center, Durham, NC, United States, 5Radiology, Duke University Medical Center, Durham, NC, United States

 
When inhaled, the moderate solubility of hyperpolarized (HP) 129Xe gives rise to two distinct resonances, in the barrier tissue and plasma (197 ppm) and in the RBC (217 ppm). This “dissolved-phase” of HP 129Xe has emerged as a non-invasive probe of pulmonary gas-transfer. While the current gold-standard to measure gas-transfer is DLCO, it is highly variable, and requires good subject compliance. In this work, we use HP 129Xe spectroscopy as a global biomarker of pulmonary gas-transfer, establish its baseline value in healthy subjects and show that it is dramatically reduced in subjects with pulmonary fibrosis.

 
2280.   Two Dimensional Radial Pulmonary Ultra-short time 1H MRI: Reproducibility in COPD and Bronchiectasis
Khadija Sheikh1,2, Weijing Ma1,2, Fumin Guo1,3, Sarah Svenningsen1,2, Terry M Peters1,2, Harvey O Coxson4, David G McCormack5, Roya Etemad-Rezai6, and Grace Parraga1,2
1Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada, 2Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada, 3Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada, 4Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada, 5Department of Medicine, The University of Western Ontario, London, Ontario, Canada, 6Department of Medical Imaging, The University of Western Ontario, London, Ontario, Canada

 
Ultra-short echo-time 1H MRI provides pulmonary 1H signal intensity (SI) measurements of tissue density. The objective of this study was to evaluate three-week reproducibility of 1H UTE MRI SI in subjects with bronchiectasis and chronic bronchitis/chronic obstructive pulmonary disease (COPD) and compare with 3He MRI measurements of apparent diffusion coefficients (ADC). This is the first evaluation of 1H UTE SI reproducibility in bronchiectasis and COPD subjects and there were high Pearson correlation coefficients, relatively low COV and high ICC; reproducibility was high and similar to 3He ADC reproducibility in the same subjects.

 
2281.   Comparison of Pulmonary 1H non-contrast and Hyperpolarized 3He MRI Ventilation Abnormalities in Bronchiectasis and COPD
Dante P Capaldi1,2, Fumin Guo1,3, Sarah Svenningsen1,2, Weijing Ma1,2, Khadija Sheikh1,2, Roya Etemad-Rezai1, Jonathon Leipsic4, Harvey O Coxson4, David G McCormack5, and Grace Parraga1,2
1Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada, 2Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada, 3Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada, 4Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada, 5Department of Medicine, The University of Western Ontario, London, Ontario, Canada

 
Free-breathing non-contrast enhanced 1H MRI ventilation imaging using Fourier decomposition has not yet been optimized at 3T or in patients with severe chronic obstructive pulmonary disease (COPD) or bronchiectasis in whom there are both airway and parenchymal abnormalities. Our objective was to compare FDMRI with hyperpolarized 3He MRI to visualize pulmonary ventilation abnormalities in subjects with bronchiectasis and COPD. Thirty subjects were evaluated using hyperpolarized 3He MRI and FDMRI of the dynamic free tidal-breathing MRI acquired over two minutes. There was excellent spatial correlation between ventilation defects visualized using both MR methods.

 
2282.   Comparison of Hyperpolarized Xenon-129 MR and Tc-99m DTPA Aerosol Lung Ventilation Imaging in Patients with COPD and Asthma
Jennifer Benjamin1, Talissa A. Altes1, Luke Lancaster1, Eduard E. de Lange1, Frank Goerner1, F. William Hersman2,3, Iulian C. Ruset3, Jaime H. Mata1, G. Wilson Miller1, Patrice Rehm1, Jason Woods4, and John P. Mugler, III1
1Radiology, University of Virginia, Charlottesville, VA, United States, 2Physics, University of New Hamshire, Durham, NH, United States, 3Xemed, Durham, NH, United States, 4Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States

 
Hyperpolarized Xe-129 MR lung ventilation imaging provides high spatial and temporal resolution images as compared with the clinical standard for lung ventilation imaging, scintigraphy. In this study, Tc-99m DTPA aerosol SPECT scintigraphy was compared with Xe-129 MR lung ventilation imaging in 14 subjects with lung disease (7 asthma and 7 COPD). Ventilation defects were depicted in greater number and conspicuity, and image quality was better with MRI.

 
2283.   Multi-Nuclear MR Imaging of Ventilation and Perfusion Distribution Response to Bronchodilator in Asthma
Helen Marshall1, Steven Thomas2, Juan Parra-Robles1, Salman Siddiqui3, Richard Kay4, Chris E Brightling3, and Jim M Wild1
1Academic Radiology, University of Sheffield, Sheffield, United Kingdom, 2Medical Physics, British Columbia Cancer Agency, British Columbia, Canada, 3Institute for Lung Health, University of Leicester, United Kingdom, 4Novartis Pharma AG, Basel, Switzerland

 
Ventilation (V) and perfusion (Q) matching is essential for efficient gas exchange in the lung. Here ventilation and perfusion distributions were imaged at baseline and post-bronchodilator in 5 patients with asthma using 3He ventilation and 1H dynamic-contrast-enhanced perfusion MRI. Maps of ventilation, peak perfusion and time-to-peak perfusion were generated and VQ distribution histograms were plotted. Individual patient VQ response to bronchodilator differed but tended towards increased and more homogeneous ventilation and perfusion post-bronchodilator. Multi-nuclear MRI provided high resolution images of regional ventilation and perfusion distributions, and was sensitive to changes in V and Q following bronchodilator administration in asthmatic patients.

 
2284.   Longitudinal Study of Pulmonary Ventilation with 3He MRI in Asthma Patients
Robert V Cadman1, David G Mummy2, Scott K Nagle1,3, Nizar N Jarjour4, Mark L Schiebler3, Ronald L Sorkness5, and Sean B Fain1,3
1Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, 2Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States,3Radiology, University of Wisconsin-Madison, WI, United States, 4Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States, 5School of Pharmacy, University of Wisconsin-Madison, Madison, WI, United States

 
Although ventilation defects are a significant feature of 3He MRI images of asthmatic lungs, the relationship of those defects to clinical symptoms of asthma is not well understood. Using longitudinal 3He MRI data, ventilation defects were classified into categories based on their behavior over time. This approach will be useful in characterizing the emergence, reversal, and persistence of such defects in asthmatic patients. Further studies will investigate the relationship between emergent ventilation defects and sites of new airway injury.

 
2285.   Comparison of global multiple breath washout measured at the mouth to imaging multiple breath washout in healthy subjects and CF patients.
Felix Horn1, Juan Parra-Robles1, Helen Marshall1, Christopher Taylor2, Alex Horsley3, and Jim Wild1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom, 2Sheffield Children's Hospital, Sheffield, South Yorkshire, United Kingdom, 3Adult CF Centre, University of Manchester, Manchester, United Kingdom

 
Previously it was shown how gas washout measured with hyperpolarized helium-3 MRI can be used to obtain quantitative regional lung function in 3D (MBW-I). Multiple breath inert gas washout as clinically performed in the pulmonary function lab (MBW) is a technique thought to be sensitive to early signs of ventilation heterogeneity in obstructive lung diseases like CF. In this preliminary work MBW-I and MBW were performed in healthy controls and CF patients. MBW-I was found to be comparable to conventional MBW, an important pre-requisite for the subsequent regional interpretation of ventilation heterogeneity.

 
2286.   Assessment of Cystic Fibrosis in Pediatric Subjects using Hyperpolarized Xenon-129 MRI: Regional Mapping of Gas Uptake by Lung Tissue and Blood
Kun Qing1, Kai Ruppert1,2, Tally A. Altes1, G. Wilson Miller1, Yun Jiang3, Jaime F. Mata1, Yun M. Shim1, Chengbo Wang1, Steven Guan1, Iulian C. Ruset4,5, F. William Hersman4,5, and John P. Mugler1
1University of Virginia, Charlottesville, VA, United States, 2Cincinnati Children's Hospital, Cincinnati, OH, United States, 3Case Western Reserve University, Cleveland, OH, United States, 4Xemed LLC, Durham, NH, United States, 5University of New Hampshire, Durham, NH, United States

 
As a non-invasive MR imaging method, 3-D Xe129 dissolved-phase imaging is particularly suited to monitoring functional changes of the lung and evaluating treatment efficacy for CF subjects, especially those in the pediatric population. In this study, we investigated functional changes in 5 pediatric subjects with CF, as compared with young healthy subjects. All tissue-to-gas ratio maps were inhomogeneous, interestingly, for all CF subjects imaged, the average tissue-to-gas ratios were higher in the right lung than the left lung , and most showed lower tissue-to-gas ratios in the right upper lobe as compared to the other lobes in the right lung.

 
2287.   
Regional Quantification of Lung Function in Cystic Fibrosis using 3D Single-Breath CSI
Steven Guan1, Kun Qing1, Talissa Altes1, John Mugler III1, Carolina Fernandes1, Kai Ruppert1, Iulian Ruset2,3, F. William Hersman2,3, Deborah Froh1, William Teague1, Grady Miller1, James Brookeman1, and Jaime Mata1
1University of Virginia, Charlottesville, VA, United States, 2University of New Hampshire, Durham, NH, United States, 3Xemed, LLC, Durham, NH, United States

 
Cystic-fibrosis (CF) is the most common, fatal, gene defect in the Caucasian population. For diseases like CF that have both obstructive and restrictive characteristics, standard pulmonary function tests can only provide a limited global assessment of ventilation parameters. 3D-Single-Breath Chemical-Shift-Imaging (3DSB-CSI) is capable of non-invasively assessing regional ventilation and multiple compartment gas uptake/exchange, which permits a better understanding of the disease and treatment efficacy. The tissue/RBC ratio maps reveal that CF subjects had a higher average tissue/RBC ratio and standard deviation, 2.96±0.74, compared to that of healthy subjects, 2.39±0.53(p=0.029). There also appears to be a good correlation (R=0.71) between the tissue/RBC ratio with the predicted FEV1. This pilot clinical study has demonstrated that 3D-SB-CSI is capable of assessing regional ventilation and multiple compartment gas uptake/exchange.

 
2288.   Imaging of Structural and Functional Changes in Early Stage CF with 3He MRI, 1H MRI and CT
Helen Marshall1, David Hughes2, Felix Horn1, Juan Parra-Robles1, Alex Horsley3, Laurie Smith2, Leanne Armstrong1, Ina Aldag2, Chris Taylor2, and Jim M Wild1
1Academic Radiology, University of Sheffield, Sheffield, United Kingdom, 2Sheffield Children's Hospital, Sheffield, United Kingdom, 3Manchester Adult CF Centre, University of Manchester, Manchester, United Kingdom

 
Early detection of lung disease is vital for effective treatment of cystic fibrosis. This study investigated the relative sensitivity of 3He ventilation MRI, 1H anatomical MRI and CT for detection of early stage lung disease in children with mild CF. 7 CF patients with normal spirometry and 5 healthy controls were studied. Abnormalities were detected in the 3He MR and CT images of 6 patients, and the 1H MR images of 3 patients. 3He MRI and CT provide complementary information about lung structure and function, and are more sensitive to early ventilation changes than 1H MRI in mild CF.

 
2289.   Comprehensive structure/function MRI of cystic fibrosis
Scott K Nagle1,2, Laura C Bell2, Christopher J Francois1, Robert V Cadman2, Stanley J Kruger2, Andrew D Hahn2, and Sean B Fain1,2
1Radiology, University of Wisconsin, Madison, WI, United States, 2Medical Physics, University of Wisconsin, Madison, WI, United States

 
MRI has significant potential advantages over CT for longitudinal surveillance of cystic fibrosis (CF) with respect to reduced radiation dose, ability to image regional function, and the potential for earlier detection of disease progression or treatment response. In this study, the performance of several MRI methods for the detection of cystic fibrosis (CF) lung disease were evaluated in comparison to CT reference standards. MRI included both functional (3He ventilation and dynamic contrast-enhanced perfusion) and anatomic/structural methods, including a 3D radial ultrashort echo time (UTE) approach. There were strong correlations between CT air trapping and He-3 MRI, perfusion MRI, and UTE MRI.

 
2290.   Measurement of Pulmonary Perfusion and Gas Exchange using Hyperpolarized 129Xe in a Rodent Model of Radiation-Induced Lung Injury
OZKAN DOGANAY1,2, MATTHEW FOX3, and GILES SANTYR1,2
1Western University, London, Ontario, Canada, 2Robarts Research Institute, London, Ontario, Canada, 3Thunder Bay Regional Research Institute, Ontario, Canada

 
We present a finite element approach for modeling hyperpolarized Xenon-129 gas exchange mechanism in the lungs. The gas exchange model interprets the chemically shift saturation recovery (CSSR) spectrum with respect to different gas exchange times to reveal functional information regarding pulmonary perfusion and diffusing capacity. In particularly, the simulation provides information about changes in the pulmonary tissue and capillaries due to radiation induced lung injury by taking advantage of unique chemical shifts of dissolved hyperpolarized Xenon-129 in pulmonary tissue and red blood cells. The model may also useful for investigating other forms of lung injury (eg. Ventilator-induced lung injury).

 
2291.   The Impact of Lung Disease on the Compartment-specific Uptake of Hyperpolarized 129Xe
Kai Ruppert1,2, Kun Qing2, Talissa A. Altes2, Jaime F. Mata2, Iulian C. Ruset3,4, F. William Hersman3,4, and John P. Mugler III2
1Cincinnati Children's Hospital, Cincinnati, OH, United States, 2University of Virginia, Charlottesville, VA, United States, 3Xemed LLC, Durham, NH, United States, 4University of New Hampshire, Durham, NH, United States

 
"Chemical Shift Saturation Recovery" (CSSR) is a method for monitoring the uptake of hyperpolarized xenon-129 (HXe) by lung parenchyma. The purpose of our studies was to investigate differences in relative HXe uptake by red blood cells (RBCs) versus lung tissue and plasma (TP) in healthy subjects, asthmatics and COPD patients. We found that the RBC-to-TP ratio (RTR) for 92% of the healthy subjects fell into a narrow range. Two groups of asthmatics, one with high and one with low RTRs could be identified while all COPD patients exhibited abnormally low RTRs.

 
2292.   REVISITING THE 129XE RELAXATION RATE IN HUMAN BLOOD AND QUANTIFYING THE RELAXIVITY OF DEOXYHAEMOGLOBIN IN THE PRESENCE OF 129XE
Graham Norquay1, General Leung1, Neil J Stewart1, Gillian M Tozer2, Jan Wolber1,3, and Jim M Wild1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom, 2Oncology, University of Sheffield, South Yorkshire, United Kingdom, 3GE Healthcare, Amersham, Buckinghamshire, United Kingdom

 
In this study, the 129Xe relaxation rate in human blood was evaluated over a large range of blood oxygenations (sO2 = 0.02 to 1.00). The 129Xe relaxation rate (R1) in red blood cells was found to vary linearly as a function of blood oxygenation, where the mechanism believed to be responsible is Xe interactions with paramagnetic deoxyhaemoglobin. A linear fit of 129Xe R1 vs the concentration of deoxyhaemoglobin ([dHb]) yielded a dHb-129Xe relaxivity of 0.035 mM-1s-1. This linear relationship may be utilised in future studies involving Xe transport from the lungs to distal tissues, organs and tumours.

 
2293.   A Preliminary Variability Study Of Hyperpolarized 3He Specific Ventilation In Human
Hooman Hamedani1, Stephen Kadlecek1, Masaru Ishii2, Yi Xin1, Hoora Shaghaghi1, Biao Han1, Sarmad Siddiqui1, Milton Rossman1, and Rahim R. Rizi1
1University of Pennsylvania, Philadelphia, PA, United States, 2Johns Hopkins University, Merryland, United States

 
Regional analysis of lung ventilation is facilitated through multi-breath Hyperpolarized gas (HP) MRI, a technique that quantifies the Specific Ventilation (SV) in parenchyma. This work presents the first preliminary short- and long-term variability of SV-MRI, and compares the imaging variability to that of pulmonary function tests (PFT).

 
2294.   In vivo observations of radiation damping effects from tissue-dissolved hyperpolarized 129Xe
Rosa Tamara Branca1,2, Le Zhang3, and Carlos Floyd4
1Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 2Biomedical Research Imaging Center, Chapel Hill, NC, United States,3Material Science, University of North Carolina at Chapel Hill, NC, United States, 4Physics and Astronomy, University of North Carolina at Chapel Hill, NC, United States

 
The low gyromagnetic ratio of xenon, the relatively low polarizability and concentration achievable in distal organs upon HP-129Xe gas inhalation suggest that in in vivo settings the observation of radiation damping is highly unlikely. Nonetheless we report the first observation of radiation damping effects from tissue-dissolved hyperpolarized xenon and a revision of the xenon uptake model to account for the strong local xenon uptake that leads to the observation of these effects.

 
2295.   In-vivo Magnetization Transfer Imaging of Mouse Lungs using a Zero Echo Time Sequence at 4.7 T – initial Experience.
Moritz C Wurnig1, Mingming Wu2, Wolfgang Jungraithmayr3, Markus Weiger4, Klaas P Pruessmann2, and Andreas Boss1
1Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Zurich, Switzerland, 2Institute for Biomedical Engineering, University and Swiss Federal Institute of Technology Zurich, Zurich, Zurich, Switzerland, 3Division of Thoracic Surgery, University Hospital Zurich, Zurich, Zurich, Switzerland, 4Institute for Biomedical Engineering, University and Swiss Federal Institute of Technology Zurich, Zurich, Zurich, Zurich, Switzerland

 
Magnetization transfer (MT) imaging of the lung is hampered by low spin-density and fast signal decay. Here we present our initial experience with zero echo time (ZTE) imaging with a MT preparation pulse applied for pulmonary MT imaging in-vivo. Experimental MTR values of non-pulmonary tissues obtained with ZTE showed the typical characteristics known from conventional MT sequences. Lung tissue itself showed MTR values between fatty tissue and liver-tissue. We could show that measuring MT in the lung in-vivo is feasible and that MT of lung tissue remains measurable even when large off-resonance frequencies are used to avoid direct saturation effects.

 
2296.   Magnetization Transfer Effect in the Lung Parenchyma: Dependence on the Presence of the Blood Signal
Pavla Francová1,2, Flavio Carinci1,2, Simon Triphan1,3, and Peter M. Jakob1,2
1Research Center Magnetic Resonance Bavaria e. V. (MRB), Würzburg, Germany, 2Department of Experimental Physics 5, University of Würzburg, Würzburg, Germany,3Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany

 
Magnetization Transfer (MT) is a promising tool for the characterization of the lung parenchyma and thus lung diseases, where e.g. the collagen content is increased. Since the mechanisms of MT in the lungs are rather unknown we investigated the influence of blood in the lung parenchyma on the MT effect. For this MTC-measurements were performed on the bloodless pig lungs and healthy volunteers group in a 1.5T scanner. The major finding was that blood has a significant influence on the MT effect.

 
2297.   Improving Image Quality of Hyperpolarized 129Xe MRI with 3D Radial Acquisition and Accurate K-Space Trajectory Measurements
Scott H Robertson1,2, Suryanarayanan S Kaushik1,3, Zackary L Cleveland1,4, Mu He1, Matthew S Freeman1,2, Rohan S Virgincar1,3, and Bastiaan Driehuys1,4
1Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States, 2Medical Physics Graduate Program, Duke University, Durham, NC, United States, 3Department of Biomedical Engineering, Duke University, Durham, NC, United States, 4Department of Radiology, Duke University Medical Center, Durham, NC, United States

 
The 3D Radial sequence has many advantages over 2D multislice GRE, namely isotropic resolution, insensitivity to diffusion, reduced signal decay effects, and the potential for very short echo times. Despite these advantages, however, 2D multislice GRE has remained the preferred sequence for hyperpolarized lung imaging. This study applies a k-space trajectory measurement technique to a 3D radial sequence, making the 3D radial image quality comparable to that of 2D multislice GRE.

 
2298.   High-resolution MRI of hyperpolarized propane at 4.7 T and 0.0475 T
Kirill V Kovtunov1, Milton L Truong2, Aaron M Coffey2, Danila A Barskiy1, Igor V Koptyug1, Kevin W Waddell2, and Eduard Y. Chekmenev2
1International Tomography Center, Novosibirsk, Novosibirsk, Russian Federation, 2Radiology, Vanderbilt University, Nashville, TN, United States

 
Fast (TR<4 ms) hyperpolarized proton MRI is presented for non-toxic propane gas prepared by heterogeneous parahydrogen induced polarization using Rh/TiO2 solid state catalyst. 3D imaging with 0.5x0.5x0.5 mm3 is demonstrated using ~1% 1H hyperpolarized propane at 4.7 T preclinical MRI system with relatively large field of view 48x48x32 mm3. Feasibility of sub-second sub-millimeter (0.9x0.9 mm2) 2D imaging of hyperpolarized propane (polarization P=0.3%) is also demonstrated at 0.0475 T preclinical MRI using frequency optimized RF coils. Hyperpolarized propane MRI can potentially be used for economical high-throughput low-field functional MRI of human lungs.

 
2299.   Rapid Pulmonary Proton ZTE Imaging in the Mouse
Mingming Wu1,2, Markus Weiger1, Moritz Christoph Wurnig3, Wolfgang Jungraithmayr4, Andreas Boss3, and Klaas Paul Pruessmann1
1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland, 2Institute of Biomedical Engineering, Karlsruhe Institute of Technology, Karlsruhe, Germany, 3Department of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland, 4Division of Thoracic Surgery, University Hospital Zurich, Zurich, Switzerland

 
Pulmonary proton MRI is conducted in mice using zero echo time (ZTE) imaging. Scan times of only 81 s for a 3D image with matrix size of 160 and isotropic resolution of 0.31 mm are achieved, yielding an SNR of 8. Further improvement of image quality is accomplished using respiratory-triggering and/or averaging at the expense of higher scan times. Additionally, ZTE imaging is demonstrated to enable T1 mapping in short T2 tissue such as in the lung where a T1 value of 660 ms is found.

 
2300.   A Method for Visualization of Parenchyma and Airspaces from 3D Ultra-Fast Balanced SSFP Imaging of the Lung at 1.5T
Oliver Bieri1
1Department of Radiology, Division of Radiological Physics, University of Basel Hospital, Basel, Switzerland

 
Only recently, a Fourier decomposition (FD) method was suggested to extract perfusion and ventilation information (parenchyma density) from a time series of co-registered 2D images. Generally, FD requires dynamic sampling with high temporal resolution and nonrigid image registration, currently limiting this technique to 2D only. Here, we introduce a simple method to visualize regional parenchyma density (ventilation) directly and in 3D using high-resolution isotropic ultra-fast balanced steady state free precession (bSSFP) scans at 1.5T acquired within a single breath-hold.

 
2301.   Design of a spin echo sequence for Fourier decomposition pulmonary MRI at 3T
Dominique M R Corteville1, Asmund Kjorstad1, Frank G Zöllner1, and Lothar R Schad1
1Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Baden Württemberg, Germany

 
Fourier Decomposition pulmonary MRI similarly to other proton techniques suffers from a low signal to noise ratio in the lung parenchyma and would benefit from being performed at higher field strength. However the bSSFP sequence used in the standard approach is not well suited for this due to its high dependency on T2*. This submission works on improving FD MRI at higher field strength by finding a replacement for the standard sequence.

 
2302.   Quantification of CPMG relaxation rate in MRI of lung tissue
Felix Tobias Kurz1, Thomas Kampf2, Sabine Heiland1, Martin Bendszus1, Heinz-Peter Schlemmer3, and Christian Herbert Ziener3
1Division of Neuroradiology, University of Heidelberg, Heidelberg, Baden-Württemberg, Germany, 2Experimental Physics 5, University of Wuerzburg, Wuerzburg, Bavaria, Germany, 3Radiology, German Cancer Research Center, Heidelberg, Baden-Württemberg, Germany

 
Recently, it has been shown that transverse relaxation rates for Carr-Purcell-Meiboom-Gill (CPMG) sequences in MRI are dependent on interpulse delay time in lung tissue. Here, a symmetry-bound physical model to describe alveolar structure is used within a well-known weak field approximation to provide an expression for transverse relaxation rate that is dependent on interpulse delay time, diffusion, alveolar radius and volumetric ratio of pulmonal air and blood volume. Theoretical results are in good agreement with experimental data for excised rat lung tissue and may be applied to determine in-vivo lung perfusion parameters in intravoxel incoherent motion models or to quantify structural parameters in lung micropathology.

 
2303.   Highly Reseolved Imaging of Hyperpolarized Helium-3 Ventilation Dynamics using fast 3-d UTE and k-t PCA
Andrew D Hahn1, Kevin M Johnson2, Grzegorz Bauman3, Robert Cadman2, Talissa A Altes4, and Sean B Fain2
1Department of Medical Physics, University of Wisconsin, Madison, Madison, Wisconsin, United States, 2Department of Medical Physics, University of Wisconsin, Madison, Wisconsin, United States, 3Department of Radiology, University of Wisconsin, Madison, Wisconsin, United States, 4Department of Radiology and Medical Imaging, University of Virginia School of Medicine, Virginia, United States

 
Hyperpolarized helium-3 gas inhalation and exhalation dynamics were recovered with high spatiotemporal resolution in a swine model utilizing a fast 3D radial UTE MRI sequence and reconstructed using k-t PCA. This technique could provide a more robust framework for investigating functional ventilation in young children who may not be able to maintain breath hold or lay still for an extended period.

 
2304.   Gravitational Distribution Gradient of Inert Fluorinated Gases in Human Lungs Using 19F Ultra-Short Echo Time MRI
Marcus J. Couch1,2, Iain K. Ball2, Tao Li2, Matthew S. Fox2, Birubi Biman3,4, and Mitchell S. Albert1,2
1Lakehead University, Thunder Bay, Ontario, Canada, 2Thunder Bay Regional Research Institute, Thunder Bay, Ontario, Canada, 3Thunder Bay Regional Health Sciences Centre, Thunder Bay, Ontario, Canada, 4Northern Ontario School of Medicine, Thunder Bay, Ontario, Canada

 
It is well-known that pulmonary ventilation exhibits a gravitational gradient due to a gradient in regional compliance. 19F MRI, using inhaled inert fluorinated gases as a signal source, is expected to exhibit strong ventilation gradients, especially since the gas density is high. The purpose of this study was to perform 19F 3D UTE imaging in healthy volunteers, and to measure anterior/posterior ventilation gradients. This preliminary study demonstrates a clear gravitational distribution gradient of inert fluorinated gases in human lungs, and there is a potential for this technique to provide functional and regional information regarding lung physiology.

 
2305.   V/Q Imaging of the Human Lung Measured at 1.5T by a Single Acquisition Technique and Tested by the Gravitational Effect
Åsmund Kjørstad1, Dominique Corteville1, Frank G. Zöllner1, Thomas Henzler2, and Lothar R. Schad1
1Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Baden-Württemberg, Germany, 2Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Baden-Württemberg, Germany

 
The ventilation to perfusion ratio (V/Q) is an important physiological parameter in the lung. Recent advantages in lung MRI have shown that both the ventilation and perfusion can separately be quantified using non-invasive and non-contrast enhanced methods. To further assess the accuracy of these methods we investigate the gravitational effect of the ventilation, perfusion and the combined V/Q maps in eight healthy volunteers.

 
2306.   MR Gravimetry (MRG) of the Lung
Oliver Bieri1
1Department of Radiology, Division of Radiological Physics, University of Basel Hospital, Basel, Switzerland

 
Computer tomograms show vertical gradients in parenchyma density due to gravity, relating to the mechanical properties of the lung. Gravitational effects on the lung were also assessed by a few occasional MRI studies, but are generally limited by the overall poor SNR of contemporary methods. Only recently a new ultra-fast balanced SSFP imaging technique was introduced, offering exceptional SNR and CNR for in vivo lung imaging at 1.5 T. This makes the investigation of gravity-related effects in the lung tissue feasible. Here, we develop the corresponding framework for such MRI investigations, termed MR Gravimetry of the lung.

 
2307.   Gas Flow Measurement using 19F-MRI during Constant and Oscillating Flow
Janet Friedrich1, Daniel Feldmann2, Maxim Terekhov1, Claus Wagner2, and Laura Maria Schreiber1
1Department of Radiology, Johannes Gutenberg University Medical Center, Mainz, Germany, 2Institute of Aerodynamics and Flow Technology, German Aerospace Center, Göttingen, Germany

 
The aim of the current study was to develop a method that enables us to measure axial velocity profiles during high frequency oscillated ventilation using 19F-MRI. This work includes constant flow measurements at Reynolds numbers Re = {10 254, 15744, 21 306} and direct numerical simulations (DNS) solving the discrete Navier-Stokes equations using a finite-volume method. Measurement and simulation results were in good agreement. Flow measurements during HFOV of 4 Hz were successfully performed and show as well a good agreement with theoretical data.

 
2308.   Reconciling the Discrepancy Between Theory and Observed Hyperpolarized 129Xe Polarizer Performance
Matthew S Freeman1,2, Kiarash Emami3, and Bastiaan Driehuys1,2
1Medical Physics Graduate Program, Duke University, Durham, NC, United States, 2Center for In Vivo Microscopy, Duke University, Durham, NC, United States, 3Polarean, Inc., Durham, NC, United States

 
While hyperpolarized (HP) 129Xe MRI shows great promise as a functional imaging modality, it remains limited by HP 129Xe polarization and production rates. Despite notable recent successes, most polarizers greatly underperform compared to theoretical predictions of the standard model of spin-exchange optical pumping (SEOP). Here we characterize 6 combinations of optical cells and lasers, and show that by postulating the generation of recently discovered paramagnetic Rb fractal clusters within the SEOP environment, observed performance can be explained. Rb fractal clusters, if confirmed, would strongly impact future polarizer designs, and if mitigated, would restore full theoretically predicted performance.

 
2309.   Preliminary Lung Density Measurements with a Portable Low-Filed System
Mikayel Dabaghyan1, Iga Muradyan2, Angelos Kyriazis2, Alan Hrovat1, James P Butler2, Samuel Patz2, and Mirko Hrovat1
1Mirtech Inc, Brockton, MA, United States, 2Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States

 
Here we present initial in vivo lung density measurements at three different lung volumes using a portable low field NMR system built in our lab. The measurements are proportional to lung density. As one predicts, the signal decreases with increasing lung volume. The measurements were highly reproducible with std < 12%. The SNR in a single 40s breath-hold at TLC was measured to be over 110. We also report initial hyperpolarized Xe measurements in a phantom using the same system with high SNR observed in a single data acquisition.

 
2310.   Optimization of a four channel phased array coil for rat lung imaging at 7 T
Dominik Berthel1, Michael Neumaier2, Dorothee Schüler1, Thomas Kaulisch2, Titus Lanz1, and Detlef Stiller2
1Rapid Biomedical GmbH, Rimpar, Germany, 2Boehringer Ingelheim Pharma GmbH & Co. KG, In-Vivo Imaging Unit, Biberach, Germany

 
Biomedical research studies with magnetic resonance examination of small animal lungs gaining in importance. Because of physiological limits at 1H lung-MRI ultra short echo time sequences (UTE) in combination with highly sensitive MR coils promises significant improvements. To increase the SNR factor of a phased array coil well decoupling of all elements are necessary. Moreover an anatomical shape of the array coil in respect to optimize the filling factor leads to higher SNR. We present an improved four channel phased array coil for rat lung imaging at 7T with elliptical housing which verifiably increases the SNR.

 
2311.   
Oxygen-dependence of T1 in lung tissue as observed in isolated, ventilated porcine lung phantoms
Simon Triphan1,2, Bertram Jobst1,3, Paul Flechsig1,3, Felix Breuer2, Peter Jakob2, and Jürgen Biederer1,4
1Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Baden-Württemberg, Germany, 2Research Centre Magnetic Resonance Bavaria e.V., Würzburg, Bayern, Germany, 3Translational Lung Research Center Heidelberg, Member of the German Lung Research Center (DZL), Heidelberg, Baden-Württemberg, Germany, 4German Cancer Research Center (DKFZ), Heidelberg, Baden-Württemberg, Germany

 
Capital Greek DeltaT1, the T1-reduction induced by breathing pure oxygen, has been used for lung functional imaging. While this effect is primarily attributed to molecular oxygen (O2) dissolved in blood, the same also occurs in tissue. Capital Greek DeltaT1 thus provides a measure of lung function comprised of various aspects. The T1 reduction in tissue alone was examined using porcine lung explants in air and oxygen atmosphere. T1 reductions of 12%, similar to those observed in vivo were measured. T1 in the bloodless explants was found to be significantly shorter than in vivo. Additionally, a measurement of a preserved explant yielded even smaller T1 and Capital Greek DeltaT1.

 
2312.   In vivo Assessment of initial Thymus Size and Age-related Thymic Involution in a C57BL/6J Mouse Strain
Abdel Wahad Bidar1, Marie Ramnegård2, Rebecka Svärd2, Janeli Sarv3, Sofia Tapani3, Josefin Forsberg4, Amir Smailagic2, Thomas G. Hansson2, and Johan Jirholt2
1R&D Personalised Healthcare & Biomarkers - Imaging, AstraZeneca, Mölndal, Sweden, 2RIA Innovative medicine, AstraZeneca, Mölndal, Sweden, 3Discovery Sciences statistics, AstraZeneca, Mölndal, Sweden, 4DSM laboratory animal, AstraZeneca, Mölndal, Sweden

 
The C57BL/6J mouse strain can serve as a convenient model for investigations of immune-based therapeutics that can enhance thymic function. In this study we demonstrate for the first time in vivo by means of MRI the natural growth and involution pattern of the thymus in a group of C57BL/6J male and female mice. Male thymus involution started before mice reached 5 weeks of age and persisted up to 8 weeks. Female thymus volume reached its maximum when mice reached 6-7 weeks old and was followed by a rapid involution rate up to an age of 10 weeks.