Jeannine A. Ruby¹, Diego Hernando¹, Camilo A. Campo¹, Ann Shimakawa², Karl K. Vigen¹, James H. Holmes³, Kang Wang³, and Scott B. Reeder^1,4,5,6,7
1Radiology, University of Wisconsin-Madison, Madison, WI, United States, ²Global MR Applications and Workflow, GE Healthcare, Menlo Park, CA, United States, ³Global MR Applications and Workflow, GE Healthcare, Madison, WI, United States, ⁴Medicine, University of Wisconsin-Madison, Madison, WI, United States, ⁵Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, ⁶Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States, ⁷Emergency Medicine, University of Wisconsin-Madison, Madison, WI, United States

In this study, we developed and validated a “single-shot” sequential 2D-chemical shift-encoded MRI (CSE-MRI) technique for motion-insensitive quantification of liver proton density fat fraction (PDFF). A phantom of 11 vials with varying PDFF demonstrated equivalent PDFF between 2D- and 3D-CSE-MRI.  Fifteen subjects underwent five different CSE-MRI acquisitions: 3D-single-breathhold (BH), slice-interleaved 2D-single-BH and free-breathing (FB), and sequential 2D-single-BH and FB.  PDFF was measured and averaged across all nine Couinaud liver segments. Good agreement was observed in PDFF between all 2D-CSE-MRI acquisitions and 3D-CSE-MRI.  Qualitative motion artifact evaluation demonstrated significantly superior scores for free-breathing “single-shot” sequential 2D-CSE-MRI compared to free-breathing slice-interleaved 2D-CSE-MRI.

Tess Armstrong^1,2, Isabel Dregely^1,3, Alto Stemmer⁴, Yutaka Natsuaki⁵, and Holden Wu^1,2
1Radiological Sciences, University of California, Los Angeles, Los Angeles, CA, United States, ²Physics and Biology in Medicine, University of California, Los Angeles, Los Angeles, CA, United States, ³Biomedical Engineering, King's College London, London, United Kingdom, ⁴Siemens Healthcare, Erlangen, Germany, ⁵Siemens Healthcare, Los Angeles, CA, United States

Non-alcoholic fatty liver disease is the leading cause of chronic liver disease. Multi-echo Cartesian MRI methods can non-invasively quantify liver fat, but are susceptible to motion artifacts and limited by breath hold (BH) imaging. We have developed a new free-breathing (FB) liver fat quantification method using non-Cartesian 3D stack-of-radial imaging. To reduce scan time, we undersampled data up to a factor of R=3. In healthy subjects, mean fat quantification was statistically equivalent among different R. Initial comparisons with spectroscopy show good agreement. Our new technique can potentially achieve accurate whole-liver fat quantification within a fast 1-minute FB scan.

Curtis N. Wiens¹, Alan B. McMillan¹, Nathan S. Artz^1,2, Rashmi Agni³, Michael Peterson⁴, Nikolaus Szeverenyi⁵, William Haufe⁵, Catherine Hooker⁵, Luke Funk⁶, Jacob Greenberg⁶, Guilherme M. Campos⁷, Santiago Horgan⁸, Garth Jacobsen⁸, Tanya Wolfson⁹, Claude Sirlin⁵, and Scott B. Reeder^{1,10,11,12,13
1}Radiology, University of Wisconsin, Madison, WI, United States, ²Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, United States, ³Pathology, University of Wisconsin, Madison, WI, United States, ⁴Tacoma General Pathology, Tacoma, WA, United States, ⁵Radiology, University of California, San Diego, CA, United States, ⁶Surgery, University of Wisconsin, Madison, WI, United States, ⁷Virginia Commonwealth University, Surgery, VA, United States, ⁸Surgery, University of California, San Diego, CA, United States, ⁹Computational and Applied Statistics Laboratory, University of California, San Diego, CA, United States, ¹⁰Medical Physics, University of Wisconsin, Madison, WI, United States, ¹¹Biomedical Engineering, University of Wisconsin, Madison, WI, United States, ¹²Medicine, University of Wisconsin, Madison, WI, United States, ¹³Emergency Medicine, University of Wisconsin, Madison, WI, United States

This study tracked changes in liver stiffness in morbidly obese patients undergoing bariatric surgery. 22 patients undergoing bariatric surgery were recruited for MRI studies including MR elastography (MRE) at 2 time points:  1-2 days prior to and 6 months after bariatric surgery. Changes in liver stiffness as measured by MRE were compared to intraoperative biopsies which were performed to assess relevant histological features (steatosis, inflammation and fibrosis) and their relation to liver stiffness. Follow-up measurement of liver stiffness 6 months after bariatric surgery showed statistically significant reductions in liver stiffness.  Patients with biopsy confirmed liver fibrosis, inflammation and features of NASH exhibited the largest reductions in liver stiffness. 

Ferenc E Mozes¹, Elizabeth M Tunnicliffe¹, Michael Pavlides^1,2, and Matthew D Robson^1
1RDM Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom, ²Translational Gastroenterology Unit, University of Oxford, Oxford, United Kingdom

The balanced steady-state free precession (bSSFP) sequence at 3T causes water and fat signals to be out of phase when TR=2.3 ms. Since the modified Look-Locker inversion recovery (MOLLI) mapping uses bSSFP readouts, the T1 of voxels that contain both fat and water is influenced by the choice of this TR. Simulations, phantom experiments and measurements collected from patients undergoing bariatric surgery were used to assess the impact of hepatic lipid content on liver MOLLI T1 values.

Kang Wang¹, Paul Manning¹, Tanya Wolfson ², Michael S. Middleton¹, Jeffrey Schwimmer³, Kimberley Newton³, Cynthia Behling³, Janis Durelle³, Melissa Paiz³, Jorge Angeles³, Meng Yin⁴, Kevin Glaser⁴, Richard Ehman⁴, and Claude Sirlin^1
1Liver Imaging Group, Department of Radiology, University of California, San Diego, School of Medicine, San Diego, CA, United States, ²Computational and Applied Statistics Laboratory, University of California, San Diego, San Diego, CA, United States,³Department of Pediatric, University of California, San Diego, San Diego, CA, United States, ⁴Departments of Radiology, Mayo Clinic, Rochester, MN, United States

We evaluated the feasibility of utilizing heterogeneity of hepatic stiffness in 3D MR elastography to improve detection of liver fibrosis in a cohort of 70 children with NAFLD. Children were dichotomized into two classes of fibrosis. We characterized the heterogeneity of hepatic stiffness by fitting a bi-Gaussian model to the histogram of hepatic stiffness. Features from the bi-Gaussian model and the known class labels were used to develop a support vector machine (SVM) classification model to predict fibrosis. We demonstrated that the SVM model has better overall classification performance than the calculated mean hepatic stiffness as measured by AUROC.

Camilo A Campo¹, Diego Hernando¹, Tilman B Schubert¹, Utaroh Motosugi^1,2, Samir D Sharma¹, Shane A Wells¹, and Scott B Reeder^1,3,4,5,6
1Radiology, University of Wisconsin-Madison, Madison, WI, United States, ²Radiology, University of Yamanashi, Yamanashi, Japan, ³Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, ⁴Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States, ⁵Medicine, University of Wisconsin-Madison, Madison, WI, United States, ⁶Emergency Medicine, University of Wisconsin-Madison, Madison, WI, United States

This study evaluated the accuracy of liver proton-density fat-fraction (PDFF) quantification in the presence of ferumoxytol. Seven healthy subjects underwent MRI scans immediately before injection of ferumoxytol and one day after injection. Our results indicate that confounder-corrected chemical shift-encoded MRI PDFF estimates exhibit a small but significant bias in the presence of ferumoxytol. This bias could be due to differential shortening in the T2* of water and fat signals. Therefore, investigators attempting to create human models of iron and fat within the liver by administering ferumoxytol to patients with fatty liver should be aware of this potential source of bias.

Manil Chouhan¹, Alan Bainbridge², Nathan Davies³, Simon Walker-Samuel⁴, Shonit Punwani¹, Mark Lythgoe⁴, Rajeshwar Mookerjee³, and Stuart Taylor^1
1UCL Centre for Medical Imaging, University College London, London, United Kingdom, ²Department of Medical Physics, University College London Hospitals NHS Trust, London, United Kingdom, ³UCL Institute for Liver and Digestive Health, University College London, London, United Kingdom, ⁴UCL Centre for Advanced Biomedical Imaging, University College London, London, United Kingdom

Total liver blood flow (TLBF) is closely regulated in health so that reductions in portal venous (PV) flow are buffered by compensatory rises in hepatic arterial (HA) flow.  In this study we use caval subtraction phase-contrast MRI to estimate TLBF and HA flow in cirrhotic rats and demonstrate an impaired HA buffer response after administering terlipressin, a vasopressin analogue used clinically used to reduce PV flow in portal hypertension.

Kang Wang¹, William Haufe¹, Nikolaus Szeverenyi¹, Alexandra Schlein ¹, Tanya Wolfson ², Michael S. Middleton¹, Jeffrey Schwimmer³, Kimberley Newton³, Cynthia Behling³, Janis Durelle³, Melissa Paiz³, Jorge Angeles³, Len Lazaro⁴, Diana De La Pena⁴, Carolyn Hernandez⁴, Rohit Loomba ⁴, Meng Yin⁵, Kevin Glaser⁵, Richard Ehman⁵, and Claude Sirlin^1
1Liver Imaging Group, Department of Radiology, University of California, San Diego, School of Medicine, San Diego, CA, United States, ²Computational and Applied Statistics Laboratory, University of California, San Diego, San Diego, CA, United States,³Department of Pediatric, University of California, San Diego, San Diego, CA, United States, ⁴NAFLD Translational Research Unit, Division of Gastroenterology, University of California, San Diego, San Diego, CA, United States, ⁵Departments of Radiology, Mayo Clinic, Rochester, MN, United States

To investigate the effect of different echo times (TE) in 2D MR elastography (2D MRE) to estimate hepatic stiffness, two 2D MRE scans were acquired in 50 patients using a 3T GE scanner, one with a default TE value of 20.1 ms (default-TE), and with a nearest in-phase TE value of 20.6 ms (IP-TE). Wave-image quality of each scan was measured quantitatively by ROI size. We demonstrated that 2D MRE with an in-phase TE provides slightly higher wave-image quality in patients with high PDFF, and potentially may be advantageous for fibrosis assessment in NAFLD.

Antonella Meloni¹, Vincenzo Positano¹, Gianluca Valeri², Gennaro Restaino³, Chiara Tudisca⁴, Paolo Preziosi⁵, Elisabetta Chiodi⁶, Maria Giovanna Neri¹, Stefano Pulini⁷, Basilia Piraino⁸, Petra Keilberg¹, and Alessia Pepe^1
1Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy, ²Azienda Ospedaliero-Universitaria Ospedali Riuniti "Umberto I-Lancisi-Salesi", Ancona, Italy, ³Fondazione di Ricerca e Cura "Giovanni Paolo II", Campobasso, Italy, ⁴Policlinico "Paolo Giaccone", Palermo, Italy, ⁵Policlinico “Casilino", Roma, Italy, ⁶Arcispedale “S. Anna”, Ferrara, Italy, ⁷Ospedale Civile “Spirito Santo”, Pescara, Italy, ⁸Policlinico "G. Martino", Messina, Italy

The aim of this multi-centre study was to retrospectively assess in thalassemia major (TM) if deferiprone (DFP) had a dose-dependent effect on liver iron concentration (LIC) assessed by quantitative magnetic resonance imaging (MRI). We found out that the percentage of patients that worsened their status was significantly higher in patients with ≤ 75 mg/kg/d  than in patients with > 75 mg/kg/d (26.6% vs 7.7%; P=0.016). So, the worsening in MRI LIC can be prevented by increasing the dose of deferiprone above the widely used regimen of 75 mg/kg body weight.

Camilo A Campo¹, Diego Hernando¹, Candice Bookwalter^1,2, Tilman B Schubert¹, and Scott B Reeder^1,3,4,5,6
1Radiology, University of Wisconsin-Madison, Madison, WI, United States, ²Radiology, Mayo Clinic, Rochester, MN, United States, ³Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, ⁴Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States, ⁵Medicine, University of Wisconsin-Madison, Madison, WI, United States, ⁶Emergency Medicine, University of Wisconsin-Madison, Madison, WI, United States

This study evaluated the reproducibility of different region-of-interest (ROI) sampling methods for MRI-based proton-density fat-fraction (PDFF) and R2* (1/T2*) measurements in the liver. 53 patient liver MRI datasets were retrospectively analyzed using ROI sampling methods that have been previously reported. Patients were not suspected of having hepatic steatosis or liver iron overload. Our results demonstrate improved measurement repeatability when the sampling area of the liver is increased by using multiple, large ROIs. Therefore, ROI-based measurements of liver PDFF and R2* should strive to sample the largest possible area of liver by using ROIs that are large in size and number.

Gavin Hamilton¹, Alexandra N Schlein¹, Adrija Mamidipalli¹, Michael S Middleton¹, Rohit Loomba², and Claude B Sirlin^1
1Department of Radiology, University of California, San Diego, San Diego, CA, United States, ²Department of Medicine, University of California, San Diego, San Diego, CA, United States

MRI based methods of estimating hepatic proton density fat fraction (PDFF) measure only one R2* value, as the R2* of fat and water are assumed to be identical. MRS can estimate the R2* of both fat and water. Liver MRS spectra were fitted with constraints derived from those used in MRI, and water R2* and fat R2*^eff (the effective fat R2* that would be measured by MRI) were compared to PDFF. We found that water R2* was independent of PDFF, while fat R2*^eff was weakly and inversely correlated with PDFF.

Xin Chen¹, Weibo Chen^2,3, Guangbin Wang⁴, Shanshan Wang⁴, Tao Gong¹, and Sai Shao^1
1Shandong University, Jinan, China, People's Republic of, ²Shanghai Key Laboratory of Magnetic Resonance and Department of Physics, East China Normal University, Shanghai, China, Shanghai, China, People's Republic of, ³Philips Healthcare, shanghai, China, Shanghai, China, People's Republic of, ⁴Shangdong Medical Imaging Research Institute, Jinan, China, People's Republic of

Liver cirrhosis is an abnormal liver condition that the liver would repair it through the deposition of collagen, proteoglycans, and other macromolecules in the extracellular matrix [1]. The risk of liver cancer is greatly increased once cirrhosis develops. A non-invasive method that can objectively and simply assessment and grade the liver fibrosis is clinically required. T1ρ relaxation time has been proven to relevant with the macromolecular composition and proton exchange of tissues[2]. It may play as a non-invasive biomarker to investigate liver fibrosis. The first whole-liver study was carried out on 1.5T MR Scanner [3]. The purpose of our study was to implement the T1ρ method with whole-liver coverage that is breathing-hold free, and to initially apply the method to evaluate severity of whole-liver cirrhosis non-invasively at 3.0T.

Manil Chouhan¹, Rajiv Ramasawmy², Adrienne Campbell-Washburn², Alan Bainbridge³, Nathan Davies⁴, Shonit Punwani¹, Rajeshwar Mookerjee⁴, Simon Walker-Samuel², Mark Lythgoe², and Stuart Taylor^1
1UCL Centre for Medical Imaging, University College London, London, United Kingdom, ²UCL Centre for Advanced Biomedical Imaging, University College London, London, United Kingdom, ³Department of Medical Physics, University College London Hospitals NHS Trust, London, United Kingdom, ⁴UCL Institute for Liver and Digestive Health, University College London, London, United Kingdom

There is a growing interest in the use of hepatic parenchymal T1 for the assessment of hepatic fibrosis.  Using Look-Locker T1 measurements at 9.4T in a rat model of cirrhosis, we demonstrate that these measurements are repeatable and significantly different in animals with and without chronic liver disease.

Huimin Lin¹, Hongjiang Wei², Chunlei Liu², Xu Yan³, Caixia Fu⁴, and Fuhua Yan^1
1Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China, People's Republic of, ²Brain Imaging and Analysis Center,Duke University, Durham, NC, United States, ³MR Collaboration NE Asia, Siemens Healthcare, Shanghai, China, People's Republic of, ⁴Siemens Shenzhen Magnetic Resonance Ltd, Shenzhen, China, People's Republic of

The purpose of this study was to estimate the Quantitative susceptibility mapping (QSM) in hepatic iron evaluation, compared with R2 based Liver concentration estimation (Ferriscan LIC). 7 Patients were scanned on a 1.5 T MR System using a GRE sequence and a SE sequence, for QSM and Ferriscan analysis respectively. QSM algorithm provided susceptibility values estimate. Approximate slices were selected according to the corresponding cross-section on the Ferriscan LIC report. Then ROIs were drawn on QSM images according to LIC maps. Significant positive correlation was observed between QSM and Ferriscan LIC ( R² = 0.8).

Eleanor F Cox¹, Naaventhan Palaniyappan², Andrew Austin³, Richard O'Neill⁴, Greg Ramjas⁴, Simon Travis⁴, Hilary White⁴, Rajeev Singh³, Peter Thurley³, Indra Neil Guha², Guruprasad Padur Aithal², and Susan T Francis^1
1SPMIC, School of Physics & Astronomy, University of Nottingham, Nottingham, United Kingdom, ²NIHR Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, United Kingdom, ³Royal Derby Hospital, Derby, United Kingdom, ⁴Department of Radiology, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom

The hepatic venous pressure gradient (HVPG) is the only validated measure to assess portal pressure but this is invasive and not widely available. Here, we use non-invasive MR parameters as a surrogate for portal pressure. Longitudinal relaxation time (T1) measures of the liver and spleen, phase contrast measures of splanchnic and collateral flow, and ASL measures of perfusion are correlated against HVPG measures in 30 patients. Liver tissue T1 is shown to be positively correlated with HVPG (p<0.001). Combining T1 measures with splenic artery velocity using a simple linear model, it is shown that HVPG can be non-invasively assessed.

Christiane Mallett¹, Matthew Latourette¹, Anna Kopec², James Luyendyk², and Erik Shapiro^1
1Radiology, Michigan State University, East Lansing, MI, United States, ²Pathobiology & Diagnostic Investigation, Michigan State University, East Lansing, MI, United States

We are developing an MRI method to measure acetaminophen toxicity in the liver. We obtained T1 maps using the clinically approved contrast agent gadoxetate disodium (Eovist). The contrast agent was administered by infusion to maintain a steady liver concentration throughout the T1 mapping. Mice with acetaminophen toxicity had higher T1 and heterogeneous gadoxetate disodium uptake compared to healthy controls. This is a promising method for quantifying drug induced liver damage in vivo.

Gavin Hamilton¹, Alexandra N Schlein¹, Adrija Mamidipalli¹, Michael S Middleton¹, Rohit Loomba², and Claude B Sirlin^1
1Department of Radiology, University of California, San Diego, San Diego, CA, United States, ²Department of Medicine, University of California, San Diego, San Diego, CA, United States

To estimate hepatic proton density fat fraction (PDFF), MRI techniques acquire multi-echo, gradient-echo images, assuming the R2* of fat and water to be identical. Liver MRS spectra were fitted with constraints derived from those used in MRI to examine this assumption. We compared fat R2*^eff (the effective fat R2* that would be measured by MRI) with water R2* and found that water R2* and fat R2*^eff were correlated. There was no significant difference between water R2* and fat R2*^eff, supporting the assumption that when measuring PDFF using MRI, fat and water R2* can be treated as identical.

Jin Yamamura¹, Sarah Keller¹, Regine Grosse², Bjoern Schoennagel¹, Peter Nielsen³, Zhiyue Jerry Wang⁴, Joachim Graessner⁵, Hendrick Kooijman⁶, Gerhard Adam¹, and Roland Fischer^3,7
1Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany, ²Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany, ³Biochemistry, University Medical Center Hamburg-Eppendorf, Hamburg, Germany, ⁴Radiology, University of Texas Southwestern Medical Center, Dallas, TX, United States, ⁵Siemens Healthcare AG, Hamburg, Germany, ⁶Philips Medical Care, Hamburg, Germany, ⁷Radiology, Children’s Hospital & Research Center Oakland, Oakland, CA, United States

We are investigating the suitability of a 3.0 T imager for iron measurements over the whole range of possible iron concentrations in the liver and spleen iron. For liver iron measurements in severely overloaded patients with LIC > 2400 µg/gliver or > 15 mg/gdry weight, 1.5 Tesla imagers are better suited than 3.0 Tesla systems. 

Kartik Jhaveri¹, Stephan Kannengiesser², Nima Sadougi³, Marshall Sussman¹, Hooman Hosseini-Nik³, Leila Zahedi³, and Richard Ward^1
1UHN,University of Toronto, Toronto, ON, Canada, ²Siemens Germany, Erlangen, Germany, ³UHN, Toronto, ON, Canada

MRI is currently utilised as a non-invasive method for liver iron concentration (LIC) estimation and has essentially replaced liver biopsy. FerriScan derived LIC is considered the “gold standard” but has associated increased costs and delay results from required external data transmittal. There is no universal agreement or standardization of R2* derived LIC methods. We describe an optimized R2* method with noise corrected post processing of data for LIC estimation with simultaneous comparison to FerriScan derived LIC. Our results show very good correlation between R2* LIC and FerriScan LIC with potential for substitution of the latter with our R2* technique. 

Adrija Mamidipalli¹, Jonathan Hooker¹, Nikolaus Szevrenyi¹, Alexandra Schlein¹, William Hauffe¹, Tanya Wolfson², Gavin Hamilton¹, Michael Middleton¹, and Claude Sirlin^1
1Liver Imaging Group, UCSD, San Diego, CA, United States, ²Computational and Applied Statistics Laboratory, San Diego Supercomputer, UCSD, San Diego, CA, United States

In this study, agreement between MRE-estimated liver stiffness using 2D GRE and SE-EPI pulse sequences at 3T was examined in 30 adults with histology-confirmed nonalcoholic fatty liver disease (NAFLD) enrolled in a research registry. Results show that liver stiffness values obtained from both the sequences agree closely across a range of liver stiffness values for adults with NAFLD, although agreement tends to diverge at higher stiffness values. Differences at higher liver stiffness values were not explained by differences in image wave quality.

Leonie Petitclerc^1,2, Guillaume Gilbert^2,3,4, Claire Wartelle-Bladou⁵, Giada Sebastiani⁶, Bich Nguyen^7,8, and An Tang^1,2,4
1Centre de recherche du Centre hospitalier de l'Universite de Montreal, Montreal, QC, Canada, ²Department of Radiology, Radio-Oncology and Nuclear Medicine, Universite de Montreal, Montreal, QC, Canada, ³Philips Healthcare Canada, Montreal, QC, Canada, ⁴Centre hospitalier de l'Universite de Montreal, Montreal, QC, Canada, ⁵Department of Gastroenterology and Hepatology, Universite de Montreal, Montreal, QC, Canada, ⁶Department of Medicine, Division of Gastroenterology, McGill University Health Centre, Montreal, QC, Canada, ⁷Department of Pathology, Centre hospitalier de l'Universite de Montreal, Montreal, QC, Canada, ⁸Department of Pathology and Cellular Biology, Universite de Montreal, Montreal, QC, Canada

Elastography for the staging of liver fibrosis is optimized for the right liver and requires additional hardware. Using MRI tagging, the displacement and strain of liver tissue induced by cardiac motion was quantified with the Harmonic Phase (HARP) method. Of the four schemes tested for the extraction of a single measure of strain, one was especially promising, as it showed high correlation with fibrosis stages (Spearman’s ρ=-0.913), as well as a significant p-value for dichotomized diagnosis of ≥F3 fibrosis (p=0.03). These preliminary results suggest that strain measurements could be used as a diagnostic tool for the staging of liver fibrosis.

Qihua Yang¹, Taihui Yu¹, Hui Zhang², Hua Guo², Yingjie Mei³, Ziliang Cheng¹, Jingwen Huang¹, and Biling Liang^1
1Radiology Dept, Sun Yat-sen Memorial Hospital, Guangzhou, China, People's Republic of, ²Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, People's Republic of, ³Philips Healthcare, Guangzhou, China, People's Republic of

To find out the relationship among T1rho, liver fibrosis stages and liver function, MRI including T1rho sequence was performed in 32 CCl4 induced liver fibrosis SD rat models and 12 SD rats of control group. Laboratory test related to liver function were done before execution and liver was taken out for pathology evaluation. Liver fibrosis was staged according to staging systems for rodents. Results showed that T1rho could be used to diagnose early liver fibrosis (>F2) and correlation was significant between T1rho values and both liver fibrosis stage and blood serum parameters.

Hui Zhang¹, Pairash Saiviroonporn², Ed X Wu^3,4, and Hua Guo^1
1Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, People's Republic of, ²Department of Radiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, ³Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China, People's Republic of, ⁴Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China, People's Republic of

To examine whether different diffusion times would yield different sensitivities in detecting the pathological alterations in tissue microstructure during liver fibrogenesis in human livers at 3 T. MRI including single-shot SE and simulated echo acquisition mode (STEAM) DWI EPI sequences were performed on 10 healthy volunteers and 19 liver fibrotic patients. One-way ANOVA with Turkey’s multiple comparison tests were employed to compare quantitative measurements between the volunteers and patients with different diffusion times. Results showed that diffusion measurements with higher diffusion times will be more sensitive as a biomarker to detect the pathological alterations in tissue microstructure in fibrotic patients.

Eamon K Doyle, MS¹, Andrew Powell, MD^2,3, and John C Wood, MD, PhD^4,5
1Biomedical Engineering, University of Southern California, Sierra Madre, CA, United States, ²Cardiology, Boston Children's Hospital, Boston, MA, United States, ³Pediatrics, Harvard School of Medicine, Boston, MA, United States, ⁴Cardiology, Children's Hospital of Los Angeles, Los Angeles, CA, United States, ⁵Biomedical Engineering, University of Southern California, Los Angeles, CA, United States

CPMG-based R2 (1/T2) estimates are traditionally insensitive to tissue iron load.  We show that the application of a T1-corrected, skeletal muscle-based proton density constraint increases the sensitivity of R2 for iron quantitation in phantoms and human subjects.  This method leads to a fundamentally different R2-LIC (liver iron concentration) calibration curve than has previously been applied to CPMG fit data.

Pelin Aksit Ciris¹, Jr-yuan George Chiou², Andriy Fedorov², Hualei Shelley Zhang², Clare Mary Tempany-Afdhal², Bruno Madore², and Stephan Ernst Maier^2,3
1Department of Biomedical Engineering, Akdeniz University, Antalya, Turkey, ²Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States,³Department of Radiology, University of Gothenburg, Gothenburg, Sweden

An accelerated multi-shot diffusion imaging sequence and reconstruction scheme was developed for prostate imaging, allowing improvements in spatial resolution, geometric-fidelity and b-factor coverage to be achieved within a short scan time. Two-fold improvement in spatial resolution and three-fold improvement in geometric fidelity were obtained as compared to single-shot EPI, in twelve prostate cancer patients. In contrast to the standard protocol, which involves separate scans with high (b=1400 and 0 s/mm²) and intermediate (b=500 and 0 s/mm²) diffusion weighting, the proposed accelerated protocol yielded an additional 8 b-factors in half the scan time (5 min 43 s vs. 11 min 48 s).

Qingsong Yang¹, Zhen Wang¹, Luguang Chen¹, Yukun Chen¹, Chao Ma¹, Caixia fu², Xu Yan³, Hui Liu³, and Jianping Lu^1
1Radiology Department, Changhai Hospital, Shanghai, China, People's Republic of, ²Application Department, Siemens Shenzhen Magnetic Resonance Ltd., Shenzhen, China, People's Republic of, ³MR Collaboration NE Asia, Siemens Healthcare, Shanghai, China, People's Republic of

Bone metastasis is a leading cause of morbidity and mortality for patients with metastatic prostate cancer. Early detection of bone metastasis plays a key role in the assessment of treatment methods and prognosis. This study aims to evaluate the diagnostic efficiency of readout-segmented whole body diffusion weighted imaging in the detection of bone metastases for patients with newly diagnosed high-risk or biochemical recurrent prostate cancer. The result shows that RESOLVE whole-body DWI has higher sensitivity, specificity and accuracy in bone metastasis detection than bone scintigraphy using 99mTc-MDP (BS).

Kevin Charles McCammack¹, Natalie M Schenker-Ahmed¹, Nathan S White¹, Shaun R Best², Robert M Marks³, Jared Heimbigner³, Christopher J Kane⁴, J Kellogg Parsons⁴, Joshua M Kuperman¹, Hauke Bartsch¹, Rahul S Desikan¹, Rebecca A Rakow-Penner¹, Michael A Liss⁵, Daniel JA Margolis⁶, Steven S Raman⁶, Ahmed Shabaik⁷, Anders M Dale¹, and David S Karow^1
1Radiology, UCSD, San Diego, CA, United States, ²Kansas City, KS, United States, ³Radiology, Naval Medical Center San Diego, San Diego, CA, United States, ⁴Urology, UCSD, San Diego, CA, United States,⁵Urology, UT San Antonio, San Antonio, TX, United States, ⁶Radiology, UCLA, Los Angeles, CA, United States, ⁷Pathology, UCSD, San Diego, CA, United States

Restriction Spectrum Imaging is an advanced, multiple b-value, diffusion technique which allows improved reader performance in the identification of prostate cancer when combined with current standard of care imaging, or performs comparably to current imaging practice when used alone.

Jessica M Winfield^1,2, David J Collins^1,2, Matthew R Orton², Jennifer C Wakefield^1,2, Andrew N Priest³, Rebecca A Quest⁴, Susan Freeman³, Andrea G Rockall⁴, and Nandita M deSouza^1,2
1MRI, Royal Marsden Hospital, Sutton, United Kingdom, ²Division of Radiotherapy and Imaging, Cancer Research UK Cancer Imaging Centre, Institute of Cancer Research, London, United Kingdom,³Department of Radiology, Addenbrooke’s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom, ⁴Imaging Department, Imperial College Healthcare NHS Trust, London, United Kingdom

The repeatability and inter-scanner reproducibility of fitted parameters from mono-exponential and non-mono-exponential (stretched exponential, kurtosis and bi-exponential) models of diffusion-weighted MRI signal attenuation were assessed in healthy volunteers and patients with advanced ovarian cancer imaged using MRI scanners from three manufacturers.

Repeatability of ADC estimates, evaluated in abdominal organs in healthy volunteers, was good on all three scanners. Estimates of DDC and α from the stretched exponential model, D_k from the kurtosis model and D from the bi-exponential model showed comparable repeatability to ADC on all three scanners; the standard deviation of differences in k was comparable across three scanners. Repeatability of f, D* and fD* was poor on all three scanners.

ADC estimates showed no significant differences between the three scanners in data from patients or healthy volunteers. Significant differences were observed between scanners in α, k, D and f in data from healthy volunteers. In lesions, there was a significant difference in k between scanners. Differences between parameters estimated from different scanners should be considered in multi-centre studies.

Kevin Charles McCammack¹, Chris J Kane², J Kellogg Parsons², Nathan S White¹, Natalie M Schenker-Ahmed¹, Kuperman M Joshua¹, Hauke Bartsch¹, Rahul S Desikan¹, Rebecca A Rakow-Penner¹, Dennis Adams³, Michael A LIss⁴, Robert F Mattrey¹, William G Bradley¹, DJA Margolis⁵, Steven Raman⁵, Ahmed Shabaik³, Anders M Dale¹, and David S Karow^1
1Radiology, UCSD, San Diego, CA, United States, ²Urology, UCSD, San Diego, CA, United States, ³Pathology, UCSD, San Diego, CA, United States, ⁴Urology, UT San Antonio, San Antonio, TX, United States,⁵Radiology, UCLA, Los Angeles, CA, United States

Restriction Spectrum Imaging, an advanced multiple b-value diffusion technique, demonstrates greater sensitivity and specificity for discriminating between tumor and normal prostate than conventional ADC or Ktrans.

Juan C. Camacho^1,2, Nima Kokabi¹, Peter A. Harri¹, Tracy E. Powell², and Sherif G. Nour^1,2
1Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, United States, ²Interventional MRI Program, Emory University Hospital, Atlanta, GA, United States

The study objective is to investigate magnetic resonance Apparent Diffusion Coefficient Quantification (ADC) in prostate lesions and to correlate the values with the results of MRI-guided prostate targeted sampling. A prospective cohort of patients presenting with persistently elevated or rising serum prostate specific antigen (PSA) and at least one lesion suspicious for prostate cancer that underwent MRI guided targeted biopsy was evaluated. Thirty-five consecutive patients were recruited presenting with 179 suspicious lesions.  ROC curve analysis demonstrates that ADC predicts the presence of malignancy and allows grade stratification and therefore, behaves as a non-invasive imaging biomarker.

Rossella Canese¹, Davide Fierro², Francesca Romana Giura², Gianmauro Palombelli¹, Elena Lucia Indino², Vincenzo Salvo², Carlo Catalano², and Valeria Panebianco^2
1Cell Biology and Neurosciences, Istituto Superiore di Sanita', Rome, Italy, ²Radiological Sciences, Oncology and Pathology, Sapienza University of Rome, Rome, Italy

To date, most clinical DW-MRI studies have employed a monoexponential model for data analysis, which produces the ADC parameter for assessing diffusion characteristics whose value correlate with Gleason scores in prostate cancer. The intravoxel incoherent motion (IVIM) model introduce a fast diffusing component in the signal due to perfusion effects, but the application of this method is not yet widespread included in clinical practice. This study was aimed at measuring the water diffusion in tissue separating and estimating the perfusion component by adopting a simple protocol easy to be implemented in clinical practice and evaluating its diagnostic performance

Nelly Tan¹, Wei-Chen Lin¹, and Steven S Raman^1
1UCLA, Los Angeles, CA, United States

MR guided Prostate Biopsy (MRgBx) yielded a Gleason upgrading in 37.5% of the patients with prior GS6 biopsy tumors. Overall diagnostic yield of MRI guided prostate biopsy was 58.3%. Men with positive MRgBx had tumors which were larger in size, lower ADC value, and higher T2, DWI and overall score compared to men with negative MRgBx. PiRADS reporting is an accurate measure to predict positive MR guided biopsy targets.

Danyan Li¹, Qinglei Zhang¹, Harsh K Agarwal², Weibo Chen², and Bin Zhu^1
1Radiology, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, China, People's Republic of, ²Philips Research NA, Cambridge, MA, MA, United States

Quantitative T2 values has the potential to reliably and reproducibly differentiate prostate abnormalities,such as prostate cancer (PCa) , benign prostate hyperplasia(BPH)and normal prostate tissue (NPT). We used k-t-T2 technique to obtain the T2 maps and tested the diagnostic performance of T2 mapping in differentiating PCa from NPT and BPH in the peripheral zone.We found the T2 values is quite useful for cancer discrimination with, for example, a threshold T2 of 68.3 ms yielded a sensitivity of 94% and a specificity of 98% for PCa discrimination.

Juan C Camacho¹, Courtney Moreno¹, Peter Harri¹, and Pardeep Mittal^1
1Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, United States

MR plays a key role in patients with abdominal visceral malignancies, regarding management, assessing therapy response and surveillance Standardized follow-up criteria and imaging techniques should be applied to patients with abdominal malignancies, taking into account the primary neoplasm and current therapeutic strategies Adequate knowledge of response evaluation criteria for malignancies including WHO, EASL, RECIST and mRECIST criteria is crucial for adequate patient surveillance.

Dianna M. E. Bardo¹, Patricia Cornejo¹, Jeffrey Miller¹, Amber Porkorney¹, Mittun Patel¹, Craig Barnes¹, Johnathan M Chia², and Houchun Harry Hu^1
1Radiology, Phoenix Children's Hospital, Phoenix, AZ, United States, ²MRI, Philips Healthcare, Highland Heights, OH, United States

mDixon sequences allow for improved MR imaging in Pediatric MR.

William M Haufe¹, Jonathan Charles Hooker¹, Alexandra N Schlein¹, Nikolaus Szeverenyi¹, Magnus Borga², Olof Dahlqvist Leinhard², Thobias Romu², Patrik Tunon², Santiago Horgan³, Garth Jacobsen³, Jeffrey B Schwimmer⁴, Scott B Reeder⁵, and Claude B Sirlin^1
1Radiology, UCSD, San Diego, CA, United States, ²AMRA, Linkoping, Sweden, ³Surgery, UCSD, San Diego, CA, United States, ⁴UCSD, San Diego, CA, United States, ⁵University of Wisconsin, Madison, Madison, WI, United States

To address the problems inherent in manual methods, a novel, semi-automated tissue segmentation image analysis technique has been developed. The purpose of this study was to demonstrate the feasibility and describe preliminary observations of applying this technique to quantify and monitor longitudinal changes in abdominal adipose tissue and thigh muscle volume in obese adults during weight loss. Abdominal adipose tissue and thigh muscle volume decreased during weight loss. As a proportion of body weight, adipose tissue volumes decreased during weight loss. By comparison, as a proportion of body weight, thigh muscle volume increased.

Janne West^1,2, Olof Dahlqvist Leinhard^1,2, Thobias Romu^2,3, E. Louise Thomas⁴, Magnus Borga^2,3, and Jimmy D. Bell^4
1Department of Medical and Health Sciences (IMH), Linköping University, Linköping, Sweden, ²Center for Medical Image Science and Visualization (CMIV), Linköping, Sweden, ³Department of Biomedical Engineering, Linköping University, Linköping, Sweden, ⁴Department of Life Sciences Faculty of Science and Technology, University of Westminster, London, United Kingdom

Water-fat separated MRI, based on Dixon imaging techniques enables high soft-tissue contrast and the separation of fat and muscle compartments. This study investigate the feasibility and success-rate of one recently described method for MR data-acquisition and body composition analysis, in a large-scale population study. The first 1,000 subjects in the UK Biobank imaging cohort were scanned, quality assured and included for body composition analysis. Volumes of visceral adipose tissue, abdominal subcutaneous tissue, and thigh muscles were calculated. This study showed that the rapid MR-examination was sufficiently robust to achieve very high success-rate for body composition analysis.

Caecilia S Reiner^1,2, Bernd Kuehn³, Daniel Nanz², Berthold Kiefer³, and Gustav Andreisek^1,2
1Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland, ²University of Zurich, Zurich, Switzerland, ³Oncology Application Predevelopment, Siemens Healthcare, Erlangen, Germany

An increasing demand for time-efficient and standardized MRI drives the development of automated MRI-workflows. The purpose of this study was to evaluate the feasibility of such a novel automated scanner-workflow for multi-station MRI. The scanner automatically detects the body regions selected and sequences are automatically adjusted to patient’s size and breath-holding capacity to generate optimal image quality. In 20 patients scanned with a multi-station protocol (chest, abdomen, and/or pelvis), image quality was good to excellent and complete body region coverage was achieved in 95% of patients. This nearly “single-button” automated multi-station MRI could open new possibilities in the diagnostic process.

Rama Jayasundar¹, Somenath Ghatak¹, Ariachery Ammini², Ashok Mukhopadhyaya³, and Arundhati Sharma^4
1NMR, All India Institute of Medical Sciences, New Delhi, India, ²Endocrinology, All India Institute of Medical Sciences, New Delhi, India, ³Laboratory Medicine, All India Institute of Medical Sciences, New Delhi, India, ⁴Anatomy, All India Institute of Medical Sciences, New Delhi, India

The world is entering an era of personalised medicine and phenotyping individuals is gaining much attention. In this context, genetic basis of the comprehensive phenotyping in ayurveda, the indigenous medicine of Indian subcontinent has drawn much scientific interest. This study reports an innovative application of MR in providing the much needed objective parameters for some of the phenotyping indices. Interestingly, the results show that the phenotypes mentioned in ayurveda as being predisposed to diabetes are found to not only have increased localised fat deposition (abdomen and thigh) (measured by MRI) and triglyceride levels but also lower insulin sensitivity.

Bart W.J. Philips¹, Stephan Orzada², Ansje Fortuin¹, Marnix C. Maas¹, and Tom W.J. Scheenen^1,2
1Radiology and Nuclear Medicine, Radboud University Medical Centre, Nijmegen, Netherlands, ²Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen, Germany

MRI of the pelvis at a high spatial resolution has potential to assess lymph node status in oncological diseases. We propose to use spectrally selective 3D gradient echo imaging in combination with TIAMO at 7 Tesla to improve upon spatial resolution using the SNR increase that ultra high field MRI provides. The method is shown to robustly obtain homogeneous, large FOV body imaging of the pelvic lymph nodes with a spatial resolution of 0.66x0.66x0.66 mm³, both for T2* weighted as well as lipid selective imaging.

Lina Avancini Colucci¹, Matthew Li¹, Kristin Corapi², Andrew Allegretti², Rayhnuma Ahmed², Herbert Y. Lin², and Michael J. Cima^3
1Health Sciences and Technology (HST), MIT, Cambridge, MA, United States, ²Division of Nephrology, Massachusetts General Hospital, Boston, MA, United States, ³Materials Science and Enginering, MIT, Cambridge, MA, United States

Incorrect assessment of clinical volume status leads to increased mortality and healthcare costs yet there are no accurate, non-invasive, and quantitative methods to assess this health metric. We evaluated the ability of a portable NMR sensor and relaxometry techniques to detect fluid changes in hemodialysis (HD) patients during the course of HD treatment. There was a significant difference between relaxation values of HD patients compared to healthy subjects.  

Weiqiang Dou¹, Simone Mastrogiacomo², Olga Koshkina³, Andor Veltien¹, Mangala Srinivas³, X. Frank Walboomers², and Arend Heerschap^1
1Radiology, Radboud University Medical Centre, Nijmegen, Netherlands, ²Biomaterials, Radboud University Medical Centre, Nijmegen, Netherlands, ³Tumor Immunology, Radboud University Medical Centre, Nijmegen, Netherlands

To enhance the MR image contrast of calcium phosphate cement (CPC) to bone, it was tagged with a ¹⁹F loaded nanoparticle as  a contrast agent. ¹⁹F zero echo time (ZTE) MRI was applied for the first time for ¹⁹F imaging of this CPC in bone at 11.7T. The T₁ and T₂^* relaxation times of the ¹⁹F nanoparticles were measured for optimal settings of ¹⁹F ZTE MRI. We demonstrate overlaid ¹H+¹⁹F ZTE images of in vitro and ex vivo CPC/bone samples with hyperintense ¹⁹F signals allowing a qualitative and quantitative evaluation of these samples. 

Jagadish Kalasthry¹, Stuart Taylor¹, David Atkinson², Alan Bainbridge³, Shonit Punwani¹, Anna Barnes⁴, and On behalf of STREAMLINE investigators^5
1Imaging, University College Hospital, London, United Kingdom, ²Centre for Medical Imaging, University College London, London, United Kingdom, ³Medical Physics and Biomedical Engineering, University College Hospital, London, United Kingdom, ⁴Clinical Physics, Institute of Nuclear Medicine, University College Hospital, London, United Kingdom, ⁵NIHR, National Institute for Health Research, London, United Kingdom

Diffusion-Weighted (DW) MRI can be used as a quantitative tool but there is limited data documenting accuracy and reproducibility on different MRI scanners with non-identical protocols. We investigated the variation in ADC measurements in normal tissue in datasets acquired as part of a pragmatic multicentre study of whole body MRI cancer and tested the impact of normalisation methods. We found large variations in ADC within both the same platform, and between different MRI platforms. Normalisation had limited benefit and only for one platform. Fat suppression seemed to be the predominant driver of variation particular in tissues outside the brain.

Takeshi Yoshikawa¹, Katsusuke Kyotani², Yoshiharu Ohno¹, Yoshimori Kassai³, Hisanobu Koyama⁴, Kouya Nishiyama², Shinichiro Seki⁴, and Kazuro Sugimura^4
1Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Japan, ²Radiology, Kobe University Hospital, Kobe, Japan, ³Toshiba Medical Systems Co., Otawara, Japan, ⁴Radiology, Kobe University Graduate School of Medicine, Kobe, Japan

To reduce distortion on abdominal EPI-DWI, we developed Fast Advanced Spin Echo (FASE)-DWI for abdominal 3T imaging. We found FASE-DWI can provide additional diagnostic information in evaluation of various abdominal diseases and be used as an alternative to EPI-DWI.

Nelly Tan¹, Noah Stier¹, Steven Raman¹, and Fabien Scalzo^1
1UCLA, Los Angeles, CA, United States

This demonstrates the feasibility of using Deep Learning to characterize prostate cancer lesions in an automatic fashion. The translation and development of this method into a decision support tool may provide more objective criteria for clinicians during diagnosis.

Amany Aziz¹, Khalid Alsabban¹, Steven M Shea¹, Ari Goldberg¹, Gopal Gupta ¹, and Joseph H Yacoub^1
1Radiology, Loyola University Medical Center, Maywood, IL, United States

Retrospective evaluation of the impact of DWI on PI-RADS scoring of TZ lesions. A blinded radiologist evaluates lesions based on only the DWI sequence and again only on the T2 TSE sequence, in separate occurrences, in patients who underwent targeted biopsy. New PI-RADS scores are given for each of the lesions. The given scores are then correlated with their corresponding Gleason scores. Of the 55 lesions studied, the DWI score downgraded four lesions from a higher T2 score. DWI could play a role in evaluation of TZ lesions, however our data lacked statistical significance.

Khalid Alsabban¹, Steven M Shea¹, Amany Aziz¹, Bryan Bisnaz², Everardo Arias², Ari Goldberg¹, Gopal Gupta³, and Joseph H Yacoub^1
1Radiology, Loyola University Medical Center, Maywood, IL, United States, ²Stritch School of Medicine, Maywood, IL, United States, ³Urology, Loyola University Medical Center, Maywood, IL, United States

The method of using an endorectal coil in a Prostate Magnetic Resonance Imaging has been an area of debate between radiologists for some time now, with a majority of research projects done to compare this method with the use of phased array coils. In this retrospective project our main objective is to identify if the temporary deforming effects caused by the use of the endorectal coil in a Prostate Magnetic Resonance Imaging (MRI) procedure may affect biopsy targeting. We will collect the dimensions measured by the MRI and compare it to the dimensions measured using the Transrectal Ultrasound procedure (TRUS).

Stephanie T. Chang¹, Andreas M. Loening¹, and Shreyas S. Vasanawala^1
1Radiology, Stanford University, Palo Alto, CA, United States

Greater diffusion weighting is generally thought to increase performance of MRI for prostate cancer detection. We compared acquired high b-value (1200 s/mm²) diffusion-weighted MRI against b-1200 images synthesized from b ≤ 800 acquisitions for detection of peripheral zone lesions in the prostate for 50 consecutive patients undergoing prostate MRI and biopsy using two blinded independent readers. Although subjective image quality was rated slightly but significantly worse for synthesized DWI compared to acquired DWI images, no significant difference in detection of peripheral zone lesions, PI-RADS version 2 lesion categorization, or confidence scores of interpretation were observed.

Mayumi Takeuchi¹, Kenji Matsuzaki^1,2, and Masafumi Harada^1
1Department of Radiology, University of Tokushima, Tokushima, Japan, ²Department of Radiological Technology, Tokushima Bunri University, Sanuki, Japan

Susceptibility-weighted (SW) magnetic resonance (MR) sequences have exquisite sensitivity to the blood products within various gynecologic pathologies, and may provide helpful information for the differential diagnosis. In this exhibit we demonstrate the role of SW sequences in diagnosing various pathologies in the female pelvis such as hemorrhagic cysts (endometrioma vs non-endometriotic cyst), extra-ovarian endometriosis and adenomyosis, gestation-associated lesions (ectopic pregnancy and retained products of conception), red degeneration of uterine leiomyoma, high-grade malignancy such as uterine sarcomas with hemorrhagic necrosis, and ovarian torsion.

Emmeli F. R. Mikkelsen¹, Per Mose Nielsen², Haiyun Qi¹, Thomas S. Nørlinger¹, Hans Stødkilde-Jørgensen¹, Niels Uldbjerg³, Michael Pedersen¹, Puk Sandager³, and Christoffer Laustsen^1
1MRI Research Centre, Aarhus University Hospital, Aarhus N, Denmark, ²Department of Clinical Medicine, Aarhus University Hospital, Aarhus N, Denmark, ³Department of Obstetrics and Gynaecology, Aarhus University Hospital, Aarhus N, Denmark

Glucose is the main energy source for the placenta and the fetus and is essential for normal growth and development of the fetus. It has previously been shown that the placenta itself consumes about half of the glucose supplied, metabolizing a great amount to lactate. Hyperpolarized Magnetic Resonance Imaging (MRI) is a novel non-harmful method for monitoring metabolic processes in tissues in real time. We evaluate the metabolism of [1-¹³C]-pyruvate in the placenta and fetus in a novel pregnancy rodent model by the use of hyperpolarized MRI.  

Nobuyuki Kosaka¹, Yasuhiro Fujiwara², Masayuki Kanamoto³, Tsuyoshi Matsuda⁴, Tatsuya Yamamoto¹, Kazuhiro Shimizu¹, Kanako Ota⁵, Yoshio Yoshida⁵, Tetsuji Kurokawa⁵, and Hirohiko Kimura^1
1Department of Radiology, University of Fukui, Eiheiji, Japan, ²Department of Medical Imaging, Kumamoto University, Kumamoto, Japan, ³Radiological Center, University of Fukui Hospital, Eiheiji, Japan, ⁴Global MR Applications and Workflow, GE Healthcare Japan Corporation, Hino, Japan, ⁵Department of Obstetrics and Gynecology, University of Fukui, Eiheiji, Japan

In this study, arterial spin-labeling (ASL)-MRI was used to evaluate the vascularity of retained products of conception (RPOCs). In 5 of 7 cases, high signals on ASL-MRI were observed, and therapeutic response could be evaluated by ASL-MRI. However, these findings of ASL-MRI were not completely identical to those of other conventional imaging modalities, such as dynamic contrast-enhanced MRI and Doppler-US. ASL-MRI is clinically feasible and can be used to assess therapeutic response. Although its clinical advantages over conventional imaging need to be evaluated, ASL-MRI has clinical potential for non-invasive assessment of RPOCs.

yu jiao zhao¹, can cui², yu zhang³, and wen shen^4
1Department of Radiology,Tianjin First Center Clinical College, Tianjin Medical University, Tianjin, Tianjin, China, People's Republic of, ²Department of Radiology, Tianjin First Center Clinical College, Tianjin Medical University, Tianjin, Tianjin, China, People's Republic of, ³Philips Healthcare, Beijing, China, beijing, China, People's Republic of, ⁴Department of Radiology, Tianjin First Center Hospital, Tianjin, China, Tianjin, China, People's Republic of

Levator ani muscle(LAM) dysfunction may cause pelvic organ prolapse(POP). DTI and fiber tracking was used to display the general morphology and microstructure changes of LAM in POP patients. We compared the FA, ADC values of pelvic floor muscles and fiber bundles shape between normal and prolapse group in this study. The results showed that the FA values of LAM muscle in prolapse group were lower than that of control and ADC values were opposite. DTI can realize the assessment of the status of LAM in patients with POP and guide the choice of operation methods.

Maelene Lohezic^1,2, Joshua van Amerom^1,2, Kelly Pegoretti², Laura McCabe², Christina Malamateniou², Olivia Carney², Matthew Fox², Joanna Allsop², Mary Rutherford², and Joseph Hajnal^1,2
1Department of Biomedical Engineering, King's College London, London, United Kingdom, ²Centre for the Developing Brain, King's College London, London, United Kingdom

Fetal MRI is a growing field but it is still far from being a standard examination and setting up a protocol demands careful optimization. Here we explore some factors to consider when choosing an appropriate slice acquisition order pattern to mitigate the effect of crosstalk between temporally consecutive slices and the partial saturation from the excitation of the adjacent slice, while taking moderate range of fetal motion into account.

Anna Andreychenko¹, Petra S. Kroon¹, Matteo Maspero¹, Ina Jürgenliemk-Schulz¹, Astrid de Leeuw¹, Marnix Lam¹, Jan J.W. Lagendijk¹, and Cornelis A.T. van den Berg^1
1UMC Utrecht, Utrecht, Netherlands

In this study a (semi-)automatic tool for red bone marrow segmentation in the pelvis was developed. The tool is solely based on MR Dixon imaging. It is intended for the dose planning for radiotherapy with the hematologic active bone marrow sparing. The optimization and validation of the tool was performed by means of FDG-PET scans of nine cervical cancer patients.

Céline Giraudeau¹, Arthur R Wijsmuller^1,2, Carter C Lebares^1,2, Jacques Marescaux^1,2, and Didier Mutter^1,2
1IHU Strasbourg, Institute of image-guided surgery, Strasbourg, France, ²IRCAD, Research Institute Against Digestive Cancer, Strasbourg, France

The goal of this study was to investigate the value of a 3D high-resolution sequence with a particular contrast to visualize and delineate pelvic autonomic nerves in a healthy volunteer. Through segmented images and the corresponding 3D reconstruction, we show that our method offers interesting results for the delineation of the hypogastric plexus and the pudendal nerves that are frequently impacted by pelvic surgery.  These results are promising for individualized preoperative mapping of autonomic innervation and could provide a valuable support to guide surgeons during interventions when combined with augmented reality.

Stephanie Giza¹, Craig Olmstead², Kevin Sinclair¹, Charles A McKenzie^1,3, and Barbra de Vrijer^3,4
1Medical Biophysics, Western University, London, ON, Canada, ²Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, ³Division of Maternal, Fetal and Newborn Health, Children's Health Research Institute, London, ON, Canada, ⁴Obstetrics and Gynecology, Western University, London, ON, Canada

Conventional ultrasound techniques perform adequately in assessment of fetal size in obese mothers but fail to identify the fetus that is chronically stressed inside the womb. A reliable MRI measurement of fetal fat volume and distribution would therefore be a powerful tool in the assessment of fetal condition.  Using a 3D LAVA-Flex sequence during maternal breath hold, fat signal fraction images were generated to measure the fat volume of the fetus, while correcting for partial volume effects. 3D water-fat MRI was found to provide a reliable measurement of fetal fat volumes that could be used to assess size and growth.

Esra Abaci Turk^1,2, Jie Luo^1,2, Borjan Gagoski ¹, Carolina Bibbo³, Julian N. Robinson³, P. Ellen Grant¹, Elfar Adalsteinsson^2,4,5, Polina Golland^4,6, and Norberto Malpica^2,7
1Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States, ²Madrid-MIT M+Vision Consortium in RLE, Massachusetts Institute of Technology, Cambridge, MA, United States, ³Maternal and Fetal Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States, ⁴Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States, ⁵Harvard-MIT Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, United States, ⁶Computer Science and Artificial Intelligence Laboratory (CSAIL), Massachusetts Institute of Technology, Cambridge, MA, United States, ⁷Medical Image Analysis and Biometry Laboratory, Universidad Rey Juan Carlos, Madrid, Spain

Abnormal oxygen transport through the placenta is thought to be a major etiologic factor in intrauterine growth restriction (IUGR). Blood-oxygen-level-dependent (BOLD) magnetic resonance imaging (MRI) with oxygen exposure is a non-invasive technique that can estimate oxygenation changes in specific organs. However, applying this technique to placentae and fetal organs can be challenging due to non-uniform signal and unpredictable fetal and maternal motion. This study presents a preprocessing pipeline to mitigate signal non-uniformities and motion, to enable automated regional analysis of placenta and fetal body for BOLD MRI studies.

Fabian Kording¹, Hendrik Kooijman², Jin Yamamura¹, Manuela Tavares³, Mathias Kladeck¹, Kurt Hecher³, Gerhard Adam¹, and Bjoern Schoennagel^1
1Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany, ²Philips Medical Systems, Hamburg, Germany, ³Department of Obstetrics and Fetal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany

Intrauterine growth restriction is associated with a decreased oxygen availability. In clinical practice, indicators such as Doppler changes of the ductus venosus and umbilical artery are measured and a direct measurement using MR oximetry would be desirable. The relationship between T2 relaxation time and oxygen saturation (sO2) is determined in in-vitro fetal blood samples and the feasibility of a noninvasively determination of fetal sO2 is evaluated. The calculated fetal sO2 highly correlated with measured sO2 values and determined parameters were successfully evaluated in-vivo in the left fetal ventricle.

Yu Y. Li¹, Wolfgang Loew¹, Ronald Pratt¹, Randy Giaquinto¹, Stephanie Merhar¹, Jean Tkach¹, and Charles Dumoulin^1
1Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States

The presented work investigates a real-time imaging approach to chest MRI on a 21.8cm bore scanner dedicated for neonatal examination within the neonatal intensive care unit (NICU). This approach is based on the development of a 10-channel small coil array, a fast imaging pulse sequence, and an iterative image reconstruction algorithm. It is experimentally demonstrated that real-time imaging can provide high-quality cardiac and pulmonary images for improved clinical diagnosis in premature babies within the NICU.

Catalina S. Arteaga de Castro¹, Jacob P. Hoogendam², Alexander Raaijmakers¹, Irene M.L. van Kalleveen¹, Wouter B. Veldhuis³, Ronald P. Zweemer², Peter R. Luijten¹, and Dennis W.J. Klomp^1
1Imaging Division, University Medical Center Utrecht, Utrecht, Netherlands, ²Gynaecological oncology, University Medical Center Utrecht, Utrecht, Netherlands, ³Radiology, University Medical Center Utrecht, Utrecht, Netherlands

The feasibility of MRSI at 7T to image fatty acid composition in cervical cancer patients was investigated . A relatively high 2.1 ppm fatty acid signal was only observed in tumor tissue. Tumor free cervix showed predominantly the 1.3 ppm lipids signal. Metabolic maps of the 2.1 ppm fatty acid showed heterogeneity within the tumor, which coincided with a hyper-intense area within the T2-weighted image, that may indicate local necrosis.

Jamie O. Lo¹, Matthias C. Schabel¹, Victoria H.J. Roberts², Xiaojie Wang², Kathleen A. Grant², Antonio E. Frias^1,2, and Christopher D. Kroenke^1,2
1Oregon Health & Science University, Portland, OR, United States, ²Oregon National Primate Research Center, Beaverton, OR, United States

Alcohol consumption in pregnancy adversely affects fetal growth and development, likely secondary to altered placental perfusion resulting in decreased fetal oxygen availability.  We developed a novel MRI technique that allows in-vivo assessment and correlation of placental perfusion and oxygenation.  Our study demonstrated reduced placental perfusion and oxygenation with first trimester ethanol exposure in a pregnant nonhuman primate model using a novel MRI method and Doppler ultrasound. Impaired fetal growth was also observed.  These findings suggest that discontinuation of alcohol consumption after the first trimester is associated with decreased placental perfusion and oxygenation subsequently affecting fetal growth and development.

Kyoko Kameyama¹, Aki Kido¹, Yuki Himoto¹, Ko Suginami², Sachiko Minamiguchi³, Ikuo Konishi², and Kaori Togashi^1
1Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan, ²Gynecology and Obstetrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan, ³Diagnostic Pathology, Graduate School of Medicine, Kyoto University, Kyoto, Japan

Half-Fourier acquisition single-shot turbo spin-echo (HASTE) imaging is now widely used for placental and fetal imaging due to its rapidity and its low sensitivity to fetal movement. We aimed to investigate the index of placental dysfunction using HASTE imaging by comparing T2-relaxation time, which is known to be one of the noninvasive biomarkers for IUGR. The placental SIR to the maternal psoas muscle (SIR_{pl/psoas muscle}) showed significant correlation with placental T2 relaxation time. There was possibility that SIR_{pl/psoas muscle} may have relation with fetal well-beings.

Xin Chen¹, Guangbin Wang², Shanshan Wang², Tao Gong¹, Sai Shao², and Tianyi Qian^3
1Shandong University, Jinan, China, People's Republic of, ²Shangdong Medical Imaging Research Institute, Jinan, China, People's Republic of, ³MR Collaborations NE Asia, Siemens Healthcare, Beijing, China, People's Republic of

The objective of the study was to identify valuable features to distinguish placenta percreta from placenta accreta and increta by retrospectively reviewing placenta MRI together with clinical findings for 46 patients diagnosed with invasive placenta. Single-shot turbo spin echo and true fast-imaging with steady-state precession sequence were included in the MR exam protocol. Two experienced radiologists evaluated seven MRI features using surgical and histopathological correlations. The features of bulging placenta including cyrtoid outline, marked placental heterogeneity and signs of placental protrusion are useful to distinguish placenta percreta from placenta accreta and increta. The wall of urinary bladder with nodular protrusion is indicative of urinary bladder involvement.

Yang Wen¹, Yun Peng¹, Dan Dan Zheng², Zhi Chen³, Guang Heng Yin¹, Yan Qiu Lv¹, Chen Xu¹, and Yang Fan^2
1Department of Radiology, Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing, China, People's Republic of, ²GE Healthcare, MR Research China, Beijing, China, People's Republic of, ³Department of Nephrology, Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing, China, People's Republic of

To evaluate the feasibility of DKI in assessment of renal functions in children with chronic kidney disease (CKD). Materials and Methods: This study was IRB approved and informed consent was obtained. Fifteen pediatric patients with CKD and nine children without renal diseases underwent DKI of kidneys. Maps of fractional anisotropy (FA), mean diffusivity (MD), mean kurtosis (MK), radial kurtosis (K_⊥) and axial kurtosis (K_//) were produced. Results: There is a significant difference of kurtosis metrics and FA of renal medulla compared to those of renal cortex in both the control group and CKD group. FA, MD, K_⊥ and MK values of both the cortex and medulla of kidney have significant differences between patients with CKD and control group. Conclusion: DKI could be a useful tool in the evaluation of renal function in children with CKD.

Tatsuo Nagasaka¹, Hideki Ota², and Hajime Tamura^3
1Radiology, Tohoku University Hospital, Sendai, Japan, ²Diagnostic Radiology, Tohoku University Graduate School of Medicine, Sendai, Japan, ³Graduate School of Medicine, Tohoku University, Sendai, Japan

We aimed to apply IVIM imaging to estimate blood oxygen saturation in kidneys with extraction of glomerular filtrate fraction by using fluid-attenuated inversion recovery diffusion-weighted imaging (FLAIR DWI). A 3-compartment model (renal tissue, blood and water) was considered for the estimation. Combination of DWI and FLAIR DWI provided renal tissue T1. Images were acquired with two TEs to provide blood T2 which allows for estimation of blood oxygen saturation. Our model generated estimation of glomerular filtrate fraction, blood R2 and blood oxygen saturation. FLAIR DWI has a potential to estimate blood oxygen saturation with extracting glomerular filtrates fractions in kidneys.

Per Mose Nielsen¹, Esben Søvsø Szocska Hansen², Thomas Nørlinger³, Rikke Nørregaard³, Lotte Bonde Bertelsen⁴, Hans Stødkilde Jørgensen⁵, and Christoffer Laustsen^3
1Clinical medicine, Aarhus university, Aarhus C, Denmark, ²MR Research Centre, institute of clinical medicine, Aarhus C, Denmark, ³Institute of clinical medicine, Aarhus C, Denmark, ⁴institute of clinical medicine, Aarhus C, Denmark, ⁵MR Research Centre, Institute of clinical medicine, Aarhus C, Denmark

Renal homeostasis is determined by the active transport of water and waste products, and the key to this is the active intra-renal transport of ions, creating the needed osmotic gradient. The maintenance of this cortico-medullary ion gradient is believed to be a measurement of kidney function.  We investigated 3D hyperpolarized ¹³C,¹⁵N-urea for mapping of this intra-renal gradient in a unilateral ischemic reperfusion renal rat model. A 3D balanced steady state sequence with an isotropic 1.25 mm resolution was used to image renal ischemic reperfusion injury. We revealed a significant reduction in the intra-renal ion gradient in the ischemic kidney.

Per Mose Nielsen¹, Christoffer Laustsen¹, Haiyun Qi¹, Thomas Nørlinger¹, Emmeli Mikkelsen¹, Rikke Nørregaard¹, and Hans Stødkilde Jørgensen^1
1institute of clinical medicine, Aarhus C, Denmark

Renal I/R-I is a leading cause of AKI in several disease states; there is a current lack of precise methods to directly assess cortical tubular injury. In the present study, we investigated the in situ alterations of metabolic conversion of pyruvate to lactate in a unilateral I/R-I rat model using [1-13C]pyruvate magnetic resonance. A significantly reduced lactate-to-pyruvate ratio of 25% as compared to control was found in the I/R-I kidney, concomitant with a reduced LDH activity, which was specific for the I/R-I kidney. The lowered lactate-to-pyruvate ratio and LDH activity strongly correlated with general tissue damage.

Christoffer Laustsen¹, Thomas Stockholm Nørlinger¹, Haiyun Qi¹, Per Mose Nielsen¹, Jakob Appel Østergaard^2,3, Allan Flyvbjerg², Jan Henrik Ardenkjaer-Larsen⁴, Fredrik Palm⁵, and Hans Stødkilde Jørgensen^1
1Department of Clinical Medicine, MR-Research Centre, Aarhus University, Aarhus, Denmark, ²Department of Endocrinology and Internal Medicine and Department of Clinical Medicine, Aarhus University, Aarhus, Denmark, ³The Danish Diabetes Academy, Odense, Denmark, ⁴Department of Electrical Engineering, Technical University of Denmark, Kgs Lyngby, Denmark, ⁵Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden

Early diabetic nephropathy (DN) disease progression is notoriously difficult to detect and quantify before substantial histological damage has occurred. Recently, hyperpolarized [1-¹³C]pyruvate has demonstrated increased lactate production, implying increased lactate dehydrogenase activity, in the kidney early after the onset of diabetes as a consequence of increased nicotinamide adenine dinucleotide (NADH) substrate availability due to elevated flux through the polyol pathway. Here we investigated whether this deranged metabolic profile can be reversed by antioxidant treatment targeting the pseudohypoxic condition.

Jon Thacker¹, Jeff Zhang², Tammy Franklin³, and Pottumarthi Prasad^3
1Northwestern University, Evanston, IL, United States, ²University of Utah, Salt Lake City, UT, United States, ³NorthShore University HealthSystem, Evanston, IL, United States

Blood oxygen level dependent (BOLD) MRI measurements generally use the transverse relaxation rate, R2*, as an indirect measure of oxygenation. While it has been shown to be related to tissue PO2, and sensitive to changes in oxygenation induced by pharmaceutical maneuvers, R2* is sensitive to other physiological parameters (e.g. hydration, hematocrit, blood perfusion) and hence not a great measure of the physiologically parameters of interest. In this study, we apply a quantitative model to BOLD MRI measurements in rodent kidneys and derive regional values for hemoglobin saturation and blood PO2. The MRI derived blood PO2 measurements are in agreement with literature.

Per Mose Nielsen¹, Abubakr Eldirdiri², Lotte Bonde Bertelsen¹, Haiyun Qi¹, Hans Stødkilde Jørgensen¹, Jan Henrik Ardenkjaer-larsen², and Christoffer Laustsen^1
1institute of clinical medicine, Aarhus C, Denmark, ²Lyngby, Denmark

Renal I/R-I is a leading cause of AKI in several disease states; there is a current lack of precise methods to directly assess cortical tubular injury. In the present study, we investigated the in situ conversion of fumarate to malate in a unilateral Ischemia/reperfusion model, which is correlated with renal tubular necrosis. We saw a strong binary [1,4-13C2]malate signal in the I/R-I kidney and a strong binary [1,4-13C2]fumarate signal in the healthy CL kidney. This was correlated with histological examinations indication renal tubular necrosis. As well as compartmentalized fumarase activity specific for I/R-I.

Emmeli F. R. Mikkelsen¹, Thomas S. Nørlinger¹, Haiyun Qi¹, Ulrich Koellisch², Rolf F. Schulte³, Michael Pedersen¹, Hans Stødkilde-Jørgensen¹, and Christoffer Laustsen^1
1MRI Research Centre, Aarhus University Hospital, Aarhus N, Denmark, ²Institute of Medical Engineering, Technische Universität München, Munich, Germany, ³GE Global Research, Munich, Germany

Positron Emission Tomography (PET) using carbon-11 acetate has previously been used to reveal the oxidative metabolism in the kidneys. It has been found that renal carbon-11 acetate turnover measured by PET was significantly correlated with renal oxygen consumption and tubular sodium reabsorption measured by an invasive approach. Hyperpolarized MRI is an alternative method to obtain similar intracellular measures of acetate, and the aim of this study was therefore to evaluate the rate constants of hyperpolarized [1-¹³C]-acetate in rat kidneys. The intrarenal oxygen level was altered by diuretics, and measures of acetate rate constants were calculated before and after injection of furosemide.

Yue Zhang¹, Payal Kapur^2,3,4, Jin Ye⁵, Qing Yuan¹, Ananth Madhuranthakam^1,6, Ivan Dimitrov⁷, Yin Xi¹, Takeshi Yokoo^1,6, Jeffrey Cadeddu^1,3, Vitaly Margulis³, Andrea Pavía-Jiménez^4,8, James Brugarolas^4,8,9, Robert E. Lenkinski^1,6, and Ivan Pedrosa^1,4,6
1Radiology, UT Southwestern Medical Center, Dallas, TX, United States, ²Pathology, UT Southwestern Medical Center, Dallas, TX, United States, ³Urology, UT Southwestern Medical Center, Dallas, TX, United States, ⁴Kidney Cancer Program, Simmons Comprehensive Cancer Center, UT Southwestern Medical Center, Dallas, TX, United States, ⁵Molecular Genetics, UT Southwestern Medical Center, Dallas, TX, United States, ⁶Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX, United States, ⁷Philips Medical Systems, Cleveland, OH, United States, ⁸Internal Medicine, UT Southwestern Medical Center, Dallas, TX, United States, ⁹Developmental Biology, UT Southwestern Medical Center, Dallas, TX, United States

We investigated the correlation between in vivo fat fraction (FF) measurements by Dixon-based MRI in clear cell renal cell carcinoma (ccRCC) and both intracellular fat accumulation at histopathology and lipidomic profile in the same tumor by mass spectrometry. Quantitative targeted fat fraction measures were obtained from representative areas within each tumor and correlated with the percentage of cells containing fat in fresh tissue samples from the same location of the tumor. Lipidomic analysis of additional tissue samples was performed. Quantitative FF measures correlated with lipid accumulation in ccRCC and provide a tool for assessing heterogeneous metabolic pathways in these tumors.

Stephen Bawden^1,2, Carolyn Chee³, Peter Mansell³, Francis Stephens³, Sally Cordon³, Mehri Kaviani², Caroline Hoad², Luca Marciani¹, Penny Gowland², Guruprasad Aithal¹, and Ian Macdonald^3
1NIHR Nottingham Digestive Diseases Research Unit, University of Nottingham, Nottingham, United Kingdom, ²Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom, ³School of Life Sciences, University of Nottingham, Nottingham, United Kingdom

This study used ¹H MRS to investigate the effects of a two week hyper-energetic 25% excess overfeeding diet of either high carbohydrate or high fat content on liver fat in 20 healthy overweight volunteers. Significant increases were found in whole group and in the high carbohydrate group, with smaller non-significant increases observed in the high fat group. Other blood measures and body fat were investigated also.

Malte Niklas Bongers¹, Norbert Stefan², Andreas Fritsche², Claus Claussen¹, Hans-Ulrich Häring², Konstantin Nikolaou¹, Fritz Schick³, and Jürgen Machann^3,4,5
1Department of Diagnostic and Interventional Radiology, University Hospital of Tübingen, Tübingen, Germany, ²Department of Endocrinology, Metabolism, Clinical Chemistry, Nephrology and Angiology, University Hospital of Tübingen, Tübingen, Germany, ³Department of Diagnostic and Interventional Radiology, Section on Experimental Radiology, University Hospital of Tübingen, Tübingen, Germany,⁴Institute for Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University of Tübingen (Paul Langerhans Institute Tübingen), Tübingen, Germany, ⁵German Center for Diabetes Research (DZD), Tübingen, Germany

Using MRI, the quantification of liver volume and identification of several compartments of adipose tissue with varying impact on metabolism is reliably possible. 1H-MRS is established as non-invasive ‘gold standard’ to quantify the amount of ectopic lipids in the liver. Lifestyle interventions show differing effects on the compartments of physiological and ectopic lipids. Caloric restriction during lifestyle interventions leads to reduced liver volume, caused by a decrease of intrahepatic lipids (IHL). The decrease of IHL shows gender specific effects on liver enzymes, primarily resulting in lowered gamma-glutamyl transferase in females and lowered alanine transaminase in males. Only in females, the decrease of IHL seems to influence the systemic low-grade inflammation positively.

Natalie Korn¹, Susan Noworolski¹, Linda Nix², Kyle Tillinghast¹, and Phyllis Tien^3,4
1Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States, ²Northern California Institute for Research and Education, San Francisco, CA, United States,³University of California, San Francisco, San Francisco, CA, United States, ⁴Department of VA Medical Center, San Francisco, CA, United States

The purpose of this work is to compare differences in visceral fat volume (by IDEAL imaging) and hepatic fat fraction (FF) (by single-voxel MRS) between African American (AA) and Caucasian (CA) men with HIV, HCV, or co-infection (HIV/HCV) against an age-matched control population. We observe AA men to have a trend towards less MR-measured visceral fat and hepatic FF than CA men in a control population. This difference was enhanced and was significant in the HIV population, while there was no observable difference in the HCV or HIV/HCV populations, indicating a need to consider both race and disease status prior to interpretation of visceral or hepatic FF findings. 

Ana Francisca Soares¹, Hongxia Lei^2,3, and Rolf Gruetter^1,2,3,4
1Laboratory of Functional and Metabolic Imaging (LIFMET), Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland, ²Center for Biomedical Imaging (CIBM), Lausanne, Switzerland,³Department of Radiology, University of Geneva (UNIGE), Geneva, Switzerland, ⁴Department of Radiology, University of Lausanne (Unil), Lausanne, Switzerland

C57BL/6J mice widely used in preclinical research exhibit sporadic congenital portosystemic shunts that prevent normal delivery of nutrients and hormones to the liver. We used MRI to diagnose portosystemic shunts in mice, and furthermore showed that their hepatic lipid content, as determined by ¹H-MRS in vivo is abnormally high. Also, compared with healthy cage mates, mice with portosystemic shunts displayed lower fasting glucose and insulin levels, with a less efficient glucose clearance after a glucose gavage. Hence, hepatic metabolism is significantly altered in mice with portosystemic shunts with consequences to whole-body glucose homeostasis.

Kyu-Ho Song¹, Chi-Hyeon Yoo¹, Song-I Lim¹, and Bo-Young Choe^1
1Department of Biomedical Engineering, and Research Institute of Biomedical Engineering, The Catholic University of Korea College of Medicine, Seoul, Seoul, Korea, Republic of

Our results of noninvasive in vivo proton magnetic resonance spectroscopy are based on accurate monitoring of the changes in lipid content, which were verified using the data on saturated fatty acids and unsaturated fatty acids.

Christian Cordes¹, Thomas Baum¹, Julia Clavel², Stefan Ruschke¹, Michael Dieckmeyer¹, Daniela Franz¹, Hendrik Kooijman³, Ernst J. Rummeny¹, Hans Hauner², and Dimitrios Karampinos^1
1Department of Diagnostic and Interventional Radiology, Technische Universitaet Muenchen, Munich, Germany, ²Else Kroener Fresenius Center for Nutritional Medicine, Technische Universitaet Muenchen, Munich, Germany, ³Philips Healthcare, Hamburg, Germany

Obesity, metabolic syndrome and diabetes are public health problems leading to increased morbidity and mortality. The present study performed fatty acid profiling of the abdominal adipose tissue by using MRS and found inverse correlations between SAT and liver fat fraction and regional distribution of adipose tissue (i.e. SAT and VAT volumes) assessed by chemical shift encoding-based water-fat MRI. This study allowed interesting insights into the obese phenotype and the reported findings may play an important role to identify different obese phenotypes, e.g. metabolically benign and insulin-resistant obese, which has clinical implications on patient treatment.

Smaragada Lamprianou¹, Jennifer Jung^2,3, Laurent Vinet¹, Rolf Gruetter^4,5,6, Paolo Meda¹, and Hongxia Lei^3,6
1Dept of Cell Physiology and metabolism, University of Geneva, Geneva, Switzerland, ²Dept of Biomedical Engineering, Imperial College, London, United Kingdom, ³Animal Imaging and Technology CIBM-AIT, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, ⁴Laboratory of functional and metabolic imaging LIFMET, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland,⁵Radiology, University of Lausanne, Lausanne, Switzerland, ⁶Radiology, University of Geneva, Geneva, Switzerland

Magnetic Resonance Imaging (MRI) at high magnetic field, with the help of manganese, a calcium analogue and a T₁ shortening contrast agent in MRI, could be beneficial for imaging murine pancreatic function.

Elin Lundström¹, Robin Strand^1,2, Anders Forslund^3,4, Peter Bergsten⁵, Daniel Weghuber^6,7, Matthias Meissnitzer⁸, Håkan Ahlström¹, and Joel Kullberg^1
1Department of Radiology, Uppsala University, Uppsala, Sweden, ²Department of Information Technology, Uppsala University, Uppsala, Sweden, ³Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden, ⁴Children Obesity Clinic, Uppsala University Hospital, Uppsala, Sweden, ⁵Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden, ⁶Department of Paediatrics, Division of Paediatric Gastroenterology, Hepatology and Nutrition, Paracelsus Medical University, Salzburg, Austria, ⁷Obesity Research Unit, Paracelsus Medical University, Salzburg, Austria,⁸Department of Radiology, Paracelsus Medical University, Salzburg, Austria

Segmentation of brown adipose tissue (BAT) from water-fat MR images generally requires time-consuming manual delineation. In this work a fully automated method, based on multi-atlas registration, for segmentation of human cervical-supraclavicular adipose tissue (suspected BAT) was evaluated using a semi-automated reference method, based on manual delineation. The presented method shows promising results for automated segmentation that allows time-efficient and objective measurements of BAT in large cohort research studies.

Sanjay Kumar Verma¹, Bhanu Prakash KN¹, Jadegoud Yaligar¹, Julian Goggi¹, Venkatesh Gopalan¹, Swee Shean Lee¹, Tian Xianfeng¹, Shigeki Sugii², Melvin Khee Shing Leow^3,4, Kishore Bhakoo¹, and S. Sendhil Velan^1
1Laboratory of Molecular Imaging, Singapore Bioimaging Consortium, Singapore, ²Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Singapore, ³Singapore Institute for Clinical Sciences, Singapore, ⁴Department of Endocrinology, Tan Tock Seng Hospital, Singapore

There are two types of fat tissues, white adipose tissue (WAT) and brown adipose tissue (BAT), which essentially perform opposite functions in whole body energy metabolism.  Cold exposure activates adrenergic receptor in the brown adipose tissues, and improve the separation of WAT and BAT. In this study we have evaluated the longitudinal changes of fat fraction (FF), and relaxation times (T₂ and T₂*) of interscapular brown adipose tissue (BAT) of rats under thermoneutral and short term cold exposure, and validated with histology and UCP1. PET-CT was performed to visualize the activated BAT.

Michael Simca Middleton¹, William Haufe¹, Jonathan Hooker¹, Magnus Borga^2,3,4, Olaf Dahlqvist Leinhard^2,3,5, Thobias Romu^2,3,4, Patrik Tunon², Nickolas Szeverenyi⁶, Gavin Hamilton⁶, Tanya Wolfson^6,7, Anthony Gamst^6,7, Rohit Loomba⁸, and Claude B. Sirlin^1
1Department of Radiology, UCSD, San Diego, CA, United States, ²Advanced MR Analytics AB (AMRA), Linkoping, Sweden, ³Center for Medical Image Science and Visualization, Linkoping University, Linkoping, Sweden, ⁴Department of Biomedical Engineering, Linkoping University, Linkoping, Sweden, ⁵Department of Medicine and Health, Linkoping University, Linkoping, Sweden, ⁶Radiology, UCSD, San Diego, CA, United States, ⁷Computational and Applied Statistics Laboratory (CASL), UCSD, San Diego, CA, United States, ⁸Department of Medicine, UCSD, San Diego, United Kingdom

Current MRI methods to estimate body tissue compartment volumes rely on manual segmentation, which is laborious, expensive, not widely available outside specialized centers, and not standardized. To address these concerns, a novel, semi-automated image analysis method has been developed. Image acquisition takes about six minutes, and uses widely available MRI pulse sequences. We found that this method permits comprehensive body compartment analysis and provides high repeatability and accuracy. Current and future clinical and drug development studies may benefit from this methodology, as may clinical settings where monitoring change in these measures is desired.

Andrew Meeker McCallister^1,2, Le Zhang^1,3, Alex Burant^1,2, Abbie Smith-Ryan⁴, Laurence Katz⁵, and Rosa Tamara Branca^1,3
1Physics, UNC Chapel Hill, Chapel Hill, NC, United States, ²Biomedical Research Imaging Center, UNC Chapel Hill, Chapel Hill, NC, United States, ³Biomedical Research Imaging Center, Chapel Hill, NC, United States, ⁴Department of Exercise and Sports Science, UNC Chapel Hill, Chapel Hill, NC, United States, ⁵Department of Emergency Medicine, UNC Chapel Hill, Chapel Hill, NC, United States

A hybrid PET-MR scanner was used to compare proposed MR techniques to the FDG PET gold standard for brown adipose tissue detection.  The subjects were cooled inside of the magnet while PET and MR fat fraction and BOLD techniques were obtained.  It was found that MR techniques alone are not sufficient to accurately predict BAT volume but can be used to increase along side PET to increase BAT specificity.

Thobias Romu^1,2, Janne West^2,3, Anna-Clara Spetz Holm⁴, Hanna Lindblom³, Lotta Lindh-Åstrand⁴, Mats Hammar⁴, Magnus Borga^1,2, and Olof Dahlqvist Leinhard^2,3
1Department of Biomedical Engineering, Linköping University, Linköping, Sweden, ²Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden, ³Department of Medical and Health Sciences (IMH), Linköping University, Linköping, Sweden, ⁴Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden

This study tested how the flip angle affects body composition analysis by MRI, if adipose tissue is used as an internal intensity reference. Whole-body water-fat images with flip angle 5° and 10° were collected from 29 women in an ongoing study. The images were calibrated based on the adipose tissue signal and whole-body total adipose, lean and soft tissue volumes were measured. A mean difference of 0.29 L, or 0.90 % of the average volume, and a coefficient of variation of 0.40 % was observed for adipose tissue.

Navin Michael¹, Suresh Anand Sadananthan¹, Mya Thway Tint², Kuan Jin Lee³, Jay Jay Thaung Zaw², Khin Thu Zar Hlaing², Pang Wei Wei², Lynette Pei-Chi Shek⁴, Yap Kok Peng Fabian^5,6, Peter D. Gluckman^1,7, Keith M. Godfrey⁸, Yap Seng Chong^1,2, Melvin Khee-Shing Leow^9,10, Yung Seng Lee^1,4, Christiani Jeyakumar Henry⁹, Marielle Valerie Fortier¹¹, and S. Sendhil Velan^1,3
1Singapore Institute for Clinical Sciences, A*STAR, Singapore, ²Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, ³Singapore BioImaging Consortium, A*STAR, Singapore, ⁴Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, ⁵Department of Paediatric Endocrinology, KK Women’s and Children’s Hospital, Singapore, ⁶Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, ⁷Liggins Institute, University of Auckland, Auckland, New Zealand, ⁸MRC Lifecourse Epidemiology Unit & NIHR Southampton Biomedical Research Centre, University of Southampton & University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom,⁹Clinical Nutrition Research Centre, Singapore Institute for Clinical Sciences, A*STAR, Singapore, ¹⁰Department of Endocrinology, Tan Tock Seng Hospital, Singapore, ¹¹Department of Diagnostic and Interventional Imaging, KK Women’s and Children’s Hospital, Singapore

The goal of this study was to understand the contribution of ethnicity, obesity and early developmental factors on IMCL determined in Asian preschoolers. Prior works on IMCL in children have found IMCL to be positively associated with childhood obesity and maternal hyperglycemia. We show that, while children with higher BMI-for-age have higher IMCL,  children born SGA also have higher IMCL at 4.5 years, despite being less obese, and despite having lower maternal BMI and maternal fasting glucose than children born AGA. We also found higher IMCL in 4.5 year-old Indian children than in Chinese and Malay children.

Suresh Anand Sadananthan¹, Navin Michael¹, Mya Thway Tint², Kuan Jin Lee³, Jay Jay Thaung Zaw², Khin Thu Zar Hlaing², Pang Wei Wei², Lynette Pei-Chi Shek⁴, Yap Kok Peng Fabian^5,6, Peter D. Gluckman^1,7, Keith M. Godfrey⁸, Yap Seng Chong^1,2, Melvin Khee-Shing Leow^9,10, Yung Seng Lee^1,4, Christiani Jeyakumar Henry⁹, Marielle Valerie Fortier¹¹, and S. Sendhil Velan^1,3
1Singapore Institute for Clinical Sciences, A*STAR, Singapore, ²Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, ³Singapore BioImaging Consortium, A*STAR, Singapore, ⁴Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, ⁵Department of Paediatric Endocrinology, KK Women’s and Children’s Hospital, Singapore, ⁶Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, ⁷Liggins Institute, University of Auckland, Auckland, New Zealand, ⁸MRC Lifecourse Epidemiology Unit & NIHR Southampton Biomedical Research Centre, University of Southampton & University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom,⁹Clinical Nutrition Research Centre, Singapore Institute for Clinical Sciences, A*STAR, Singapore, ¹⁰Department of Endocrinology, Tan Tock Seng Hospital, Singapore, ¹¹Department of Diagnostic and Interventional Imaging, KK Women’s and Children’s Hospital, Singapore

Children born small-for-gestational age (SGA) are at an increased risk of developing diabetes and obesity. In vitro studies have shown higher lipid content in adipocytes differentiated from mesenchymal stem cells obtained from the umbilical cord of SGA neonates compared to appropriate-for-gestational age (AGA) infants. However, validating this in children is difficult as assessment of adipocyte hypertrophy has traditionally necessitated adipose tissue biopsies. In earlier studies, we have shown that hydrolipidic ratio (HLR) determined using MRS is negatively associated with adipocyte hypertrophy. In this work, we examined the size-for-gestational age specific differences in abdominal subcutaneous fat and HLR in Asian preschoolers.

Venkatesh Gopalan¹, Jadegoud Yaligar¹, Navin Michael², Lee Swee Shean¹, Suresh Anand Sadananthan², Anna Ulyanova¹, Bhanu Prakash KN¹, and S Sendhil Velan^1
1Laboratory of Molecular Imaging, Singapore Bio-Imaging Consortium, BioMedical Sciences, Singapore, Singapore, ²Singapore Instiute for Clinical Sciences, Singapore, Singapore

The goal of this study was to investigate how dietary fat intake modulates the effect of long term exercise training on body weight, intrahepatic and intramyocellular lipids (IHL & IMCL), and effect on insulin sensitivity in an animal model of long-term exercise. Long term exercise was found to result in significant elevations in IMCL and IHL under low fat background diet, and significant reductions in IMCL and IHL under a high fat background diet, compared to sedentary diet-matched controls. Dietary fat content did not modulate the effect of exercise on insulin sensitivity.  

Curtis N. Wiens¹, Alan B. McMillan¹, Nathan S. Artz^1,2, William Haufe³, Camilo A. Campo¹, Alexandria Schlein³, Luke Funk⁴, Jacob Greenberg⁴, Guilherme M. Campos⁵, Claude Sirlin³, and Scott B. Reeder^1,6,7,8,9
1Radiology, University of Wisconsin, Madison, WI, United States, ²Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, United States, ³Radiology, University of California, San Diego, CA, United States, ⁴Surgery, University of Wisconsin, Madison, WI, United States, ⁵Surgery, Virginia Commonwealth University, Richmond, VA, United States, ⁶Medical Physics, University of Wisconsin, Madison, WI, United States, ⁷Biomedical Engineering, University of Wisconsin, Madison, WI, United States, ⁸Medicine, University of Wisconsin, Madison, WI, United States, ⁹Emergency Medicine, University of Wisconsin, Madison, WI, United States

The purpose of this work was to determine the relationship between proton density fat fraction (PDFF) and metabolic syndrome (MetS) in obese patients. Patients were recruited for an MRI study 1-2 days prior to weight loss surgery (WLS). A subset of these patients with biopsy confirmed hepatic steatosis were recruited for a second MRI 6 months post WLS. A cut-off PDFF of 7.5% had a sensitivity of 77% and specificity of 80% for predicting MetS prior to undergoing WLS. At 6 months follow-up, patients with confirmed hepatic steatosis had significantly decreased prevalence of MetS (91% to 52%). Additionally, other metabolic, biometric, and imaging (PDFF) markers related to MetS were significantly reduced.

Bhanu Prakash KN¹, Venkatesh Gopalan¹, Swee Shean Lee¹, and Sendhil Velan S^1,2
1Laboratory of Metabolic Imaging, Singapore Bioimaging Consortium, Singapore, Singapore, ²Singapore Institute for Clinical Sciences, Singapore, Singapore

Quantification of adipose tissue distribution within the abdomen   is fundamental for investigations in obesity and diabetes.   Distribution of fat within the body, and its accumulation in the abdominal cavity, exert different physiologic effects based on their anatomical location. Calorie-restriction and exercise interventions improve obesity risk factors.   Fat accumulation and mobilization can vary depending on the type and quality of fat in different locations.  We have investigated the quantitative changes in fat volumes at different positions in the abdomen in diet induced obese rats.

Jadegoud Yaligar¹, Sanjay Kumar Verma¹, Bhanu Prakash KN¹, Tian Xianfeng¹, Venkatesh Gopalan¹, Swee Shean Lee¹, Suresh Anand Sadananthan², Navin Michael², Ong Wee Kiat³, Shigeki Sugii ³, and S Sendhil Velan^1
1Laboratory of Metabolic Imaging, Singapore Bioimaging Consortium, A*STAR, Singapore, ²Singapore Institute for Clinical Sciences, A*STAR, Singapore, ³Fat Metabolism and Stem Cell Group, Singapore Bioimaging Consortium, A*STAR, Singapore

Obesity and diabetes are major metabolic disorders associated with dietary intake.  Brown adipose tissue (BAT) is major site for adaptive thermogenesis involving uncoupling protein-1. We performed longitudinal imaging of fat fraction (FF) of interscapular BAT in control and high fat diet fed rats under thermoneutral and cold exposure conditions on Wistar rats of 7, 11 and 15 weeks.  High fat diet results in increased fat fraction in iBAT. Histology shows increased size of brown adipocytes which may alter BAT function and influence thermogenic potential.  UCP1 was upregulated in HFD groups. With cold exposure FF reduced significantly in control and HFD groups.

Haley R Clark¹, Ivan Pedrosa^1,2, Ildiko Lingvay^3,4, Muhammad Beg³, Ion A Bobulescu³, and Takeshi Yokoo^1,2
1Radiology, University of Texas Southwestern Medical Center, Dallas, TX, United States, ²Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States,³Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States, ⁴Clinical Science, University of Texas Southwestern Medical Center, Dallas, TX, United States

In this retrospective pilot study, proton-density fat fraction (PDFF) of kidneys was compared in 40 and 29 adult subjects without and with type 2 diabetes mellitus (DM2), respectively.  Median PDFF was significantly higher in DM2 (2.18%) than non-DM2 subjects (0.78%), with p=0.0008.  Statistically significant correlation was found between renal PDFF and body-mass-index (BMI; r=0.2661, p=0.027).  After correcting for age, sex, and BMI, PDFF difference due to DM2 remained statistically significant with p=0.0045. 

Martin Buechert¹, Frederike Wilbert², Thomas Lange³, Sara Tucci², and Ute Spiekerkoetter^2
1Magnetic Resonance Development and Application Center (MRDAC), University Medical Centre, Freiburg, Germany, ²Department of Pediatrics, Adolescent Medicine and Neonatology, University Medical Center, Freiburg, Germany, ³Medical Physics, Department of Radiology, University Medical Center, Freiburg, Germany

Deficiency of very-long-chain acyl-CoA dehydrogenase is the most common inherited disorder of mitochondrial β-oxidation of LCFAs with an incidence of about 1:50,000 to 1:100,000 newborns. The clinical phenotype is very heterogeneous, involving organs and tissues that mostly rely on fatty acid β-oxidation for energy production. In order to develop new monitoring and treatment strategies various approaches to characterize such patients are tested. Here a multimodal MR-approach already applied in a pre-clinical setting is transferred to humans within a pilot study. Cardiac MRI is combined with Dixon-fat/water MRI and liver MR-spectroscopy.

Keizo Tanitame¹, Yuji Takahashi², Yoko Kaichi³, Akira Naito¹, and Kazuo Awai^3
1Radiology, Chugoku Rosai Hospital, Kure, Japan, ²Clinical radiology, Hiroshima University Hospital, Hiroshima, Japan, ³Diagnostic Radiology, Hiroshima University Hospital, Hiroshima, Japan

We believe that the quantitative evaluation of orbital fat proliferation and edema is useful for diagnosing and monitoring Graves’ ophthalmopathy. We demonstrate the feasibility of orbital fat volumetry and fat fraction measurement using iterative decomposition of water and fat with echo asymmetry and least-squares estimation-fast spin echo (IDEAL-FSE) and analyze preliminary data from healthy adults.

Tameshwar Ganesh^1,2, Marvin Estrada³, James Duffin⁴, and Hai-Ling Margaret Cheng^1,2,5,6
1Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada, ²Physiology & Experimental Medicine, Hospital for Sick Children Research Institute, Toronto, ON, Canada, ³Lab Animal Services, Hospital for Sick Children, Toronto, ON, Canada, ⁴Anesthesia, University of Toronto, Toronto, ON, Canada, ⁵Institute of Biomaterials & Biomedical Engineering, University of Toronto, Toronto, ON, Canada, ⁶The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, University of Toronto, Toronto, ON, Canada

Inspiring gases with altered O2 and CO2 levels is an approach to assess the health of the cerebral vasculature. However, application of this technique in the body is new and less well understood compared to its application in the brain. In this study, we adopt a comprehensive approach to investigate the MR signatures of abdominal tissue response to a wide spectrum of gas challenges. Results in the liver, kidney, and muscle of healthy rats confirmed T2* as a robust marker of blood oxygen saturation but suggested that T1, other than its conventional association to tissue oxygenation, may a marker of blood volume changes.

Amanda D MacCannell¹, Kevin J Sinclair², Lanette J Friesen-Waldner², Charles A McKenzie², and James F Staples^1
1Biology, Western University, London, ON, Canada, ²Medical Biophysics, Western University, London, ON, Canada

During winter, brown adipose tissue (BAT) is the primary source of heat production in hibernating animals.  White adipose tissue volumes increase and BAT-specific genes are upregulated in autumn even when temperatures are warm, but the rhythm of changes in BAT volume is unknown.  Water-fat MRI was used to measure total BAT volume in hibernating squirrels two months after arousing from hibernation in spring and again at 18 days following the first MRI scan.  BAT volumes increased significantly in this 20 day time period.

Diego Hernando¹, Ildiko Kasza², Scott B Reeder^1,3,4,5,6, and Caroline M Alexander^2
1Radiology, University of Wisconsin-Madison, Madison, WI, United States, ²McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI, United States, ³Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, ⁴Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States, ⁵Medicine, University of Wisconsin-Madison, Madison, WI, United States, ⁶Emergency Medicine, University of Wisconsin-Madison, Madison, WI, United States

Dermal white adipose tissue (DWAT) has only recently been recognized as a distinct adipocyte depot, with the potential to influence metabolism and physiology. In this study, we introduce a fat-water MRI approach for noninvasive quantification of the DWAT layer in mice on a clinical 3T scanner, and validate this approach using histology. As shown by MRI and histology, DWAT is thinner in Sdc1-/- mice compared to wild type. Interestingly, DWAT was dramatically thicker in an obese mouse model.