Houchun Harry Hu^1,2, Yan Li³, Tim R. Nagy³, Michael I. Goran⁴, and Krishna S. Nayak^2
1Radiology, Children's Hospital of Los Angeles, Los Angeles, California, United States, ²Electrical Engineering, University of Southern California, Los Angeles, California, United States, ³Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama, United States, ⁴Preventive Medicine, University of Southern California, Los Angeles, California, United States

We validated an approach using the proton density fat fraction (PDFF) metric derived from chemical-shift water-fat MRI to compute absolute fat mass (in grams). The approach was validated in 97 freshly excised organ, muscle, and adipose tissue samples from four pigs against reference chemical analysis (CA). A strong agreement between MRI and CA-derived fat mass was obtained (slope=1.01, intercept=1.99g, r²=0.98, p<0.01). The mean difference between MRI and CA was 2.17±3.4g. The results suggest that PDFF provides an accurate means of determining absolute fat mass and can facilitate quantitative fat MRI comparisons against traditional body composition techniques in animals and humans.

A Pola¹, S Tan², T Y Keong³, Z Zhou², S A Sadananthan¹, G Venkatesh³, S Ishino⁴, Y Nakano⁴, M Watanabe⁴, T Horiguchi⁴, B Zhu², and S Sendhil Velan^3
1Singapoe Institute for Clinical Sciences, A*STAR, Singapore, ²Takeda Singapore Pte Ltd, Singapore, ³Laboratory of Molecular Inaging, Singapore Bioimaging Consortium, Singapore, ⁴Takeda Pharmaceutical Company Limited, Japan

Current measurements to evaluate the anti-obesity effects are focused on the decrease of the body weight and visceral fat which takes longer time to show the effect, therefore a biomarker to predict anti-obesity effects for short term is of interest. In this study, we investigated the variation in body weight, intra-hepatic lipid, intra-myocellular lipid and visceral fat, in a series of studies using calorie restriction and an anti-obesity drug (Sibutramine) treatment for 4 weeks in a diet induced obese rat model. Our findings demonstrate that MRI/MRS can be utilized to evaluate the therapeutic potential of novel drugs in rodent models of obesity and diabetes.

Houchun Harry Hu^1,2, Thomas G. Perkins³, Jonathan M. Chia³, and Vicente Gilsanz^1
1Radiology, Children's Hospital of Los Angeles, University of Southern California, Los Angeles, California, United States, ²Electrical Engineering, University of Southern California, Los Angeles, California, United States, ³Philips Healthcare, United States

We utilized chemical-shift water-fat MRI techniques to measure T2* relaxation times in human adipose tissue. In oncology patients and healthy volunteers, we have consistently observed in suspected sites of interscapular brown adipose tissue (BAT) an evident decrease in T2* in comparison to subcutaneous white adipose tissue (WAT). The lower T2* values in BAT can be attributed to the tissue’s greater vascularization and mitochondria (iron) content. On anatomical images, fat pads with seemingly homogeneous fat signals exhibit rather heterogenous distributions on the co-registered quantitative T2* maps, supportive of the notion that small clusters of BAT adipocytes are likely interspersed amongst WAT.

Aliya Gifford^1,2, Johan Berglund³, Joel Kullberg³, Theodore F Towse¹, Malcolm J Avison^1,4, and E. Brian Welch^1,5
1Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, ²Chemical and Physical Biology Program, Vanderbilt University, Nashville, TN, United States,³Department of Radiology, Uppsala University Hospital, Uppsala, Sweden, ⁴Department of Pharmacology, Vanderbilt University, Nashville, TN, United States, ⁵Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States

Brown adipose tissue (BAT) is a thermogenic tissue which recent 18F-FDG PET and CT studies have imaged and confirmed the presence of in adult humans. Reliable identification and spatial mapping methods that avoid radiation exposure and can distinguish BAT from white adipose tissue (WAT) would provide a powerful tool with which to study BAT’s influence on body composition. We hypothesize that BAT may be visualized and quantified in humans using fat-water MRI (FWMRI). Whole-body 3T FWMRI scans were performed on two adult male humans, which revealed tissue with characteristics (location, size and fat signal fraction) associated with BAT.

Houchun Harry Hu^1,2, Jason P. Tovar³, Zdena Pavlova³, Thomas G. Perkins⁴, and Vicente Gilsanz^1
1Radiology, Children's Hospital of Los Angeles, Los Angeles, California, United States, ²Electrical Engineering, University of Southern California, Los Angeles, California, United States, ³Pathology, Children's Hospital of Los Angeles, Los Angeles, California, United States, ⁴Philips Healthcare, Cleveland, Ohio

We report the unique depiction of brown adipose tissue (BAT) by MRI and CT in a human three month-old infant. Based on cellular differences between BAT and more lipid-rich white adipose tissue (WAT), chemical-shift MRI and CT were both capable of generating distinct and complementary signal contrasts between the two tissues and against surrounding anatomy, utilizing T1-weighted fat-signal fraction in the former and X-ray attenuation in the latter. Large bilateral supraclavicular BAT depots (17 ml in total volume) were clearly visualized by both modalities, and identified tissues were subsequently confirmed by biopsy and histological analysis.

Gregor Thörmer¹, Henriette Helene Bertram¹, Veronika Peter², Tatjana Schütz², Edward Shang², Matthias Blüher³, Thomas Kahn¹, and Harald Busse^1
1Dept. of Diagnostic and Interventional Radiology, Leipzig University Hospital, Leipzig, Saxony, Germany, ²Dept. of Visceral, Transplantation, Thoracic and Vascular Surgery, Section Bariatric Surgery, Leipzig University Hospital, Leipzig, Saxony, Germany, ³Dept. of Endocrinology and Nephrology, Leipzig University Hospital, Leipzig, Saxony, Germany

The risk of obesity-related diseases can be assessed by MRI estimates of the abdominal fat distribution. Computer-assisted techniques can be used for rapid image segmentation, but any unsupervised analysis is prone to errors caused by anatomical variations and artifacts, in particular for advanced stages of obesity. A custom-made software with a user interface for the rapid inspection of automatically segmented images was evaluated on the example of 20 extremely obese patients (mean BMI=44 kg/m2) and compared to manual processing by two observers. The presented software appears to be promising for accurate and time-effective fat quantification and larger segmentation errors can be easily corrected in the graphical user environment.

Qi Feng¹, Jiong Zhu¹, Qing Lu¹, He Wang², Jia Hua¹, and Jianrong Xu^1
1Renji Hospital affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China, China, ²Applied Science Lab, GE Healthcare, Shanghai, China

Diffusion-weighted imaging sequences at high b values could identify disease-active and disease-inactive intestinal segments clearly and a b value of 1500 offered the best balance of diagnostic sensitivity and specificity in this current study.

Moti Freiman¹, Jeannette M Perez-Rossello¹, Michael J Callahan¹, Mark Bittman¹, Robert V Mulkern¹, Athos Bousvaros², and Simon K Warfield^1
1Radiology, Children's Hospital Boston/Harvard Medical School, Boston, MA, United States, ²Inflammatory Bowel Disease Center, Children's Hospital Boston/Harvard Medical School, Boston, MA, United States

Alex Menys¹, Freddy Odille², Shonit Punwani³, Marco Novelli⁴, Manuel Rodriguez-Justo⁴, Steve Halligan³, David Atkinson³, and Stuart Taylor^3
1Centre for Medical Imaging, University College London, UCLH, London, United Kingdom, ²INSERM U947, Université de Lorraine, Nancy, France, ³Centre for Medical Imaging, University College London, ⁴Department of Gastrointestinal Pathology, University College London Hospital

Optimal medical management of Crohn’s disease (CD) relies on accurate identification of patients with acute inflammation. Currently a number of anatomical features seen on MR enterography have been shown to correlate closely with disease activity. Abnormal intestinal motility has been described in CD and may also be a marker for disease activity. We explored quantitatively the relationship between CD activity and intestinal motility assessed using MRI (n=23) against a histopathological standard of reference and validated anatomical MRI markers of activity. We found significant relationships between motility and both end points suggesting motility as a biomarker for inflammatory activity.

Caroline L Hoad¹, Klara Garsed², Luca Marciani², Eleanor F Cox¹, Carolyn Costigan¹, Robin C Spiller², and Penelope A Gowland^1
1Physics and Astronomy, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, ²Nottingham Digestive Diseases Centre, NIHR Biomedical Research Unit, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom

T₁ of the chyme in the ascending colon (AC) was measured using an inversion recovery TrueFISP sequence in healthy volunteers and patients with diarrhoea predominant irritable bowel syndrome (IBS-D). Data was fitted to both 1-compartment and 2-compartment T₁ models. IBS-D patients showed a higher mean T₁ in the chyme of their AC than the healthy volunteers for both the 1-compartment and short component of the 2-compartment model. This difference may have been due to faster small bowel transit or a reduced rate of fluid absorption in the AC.

Mahamoud Omar Hussein ¹, Luca Marciani², Caroline L. Hoad¹, Mary Stephenson¹, Eleanor F Cox¹, Elisa Placidi¹, Susan Pritchard¹, Carolyn Costigan¹, Henelyta Ribeiro³, Elisabetta Ciampi³, Pip Rayment³, Asish Nandi³, Nick Hedges³, Paul Sanderson³, Harry Peters F Peters⁴, Robin C. Spiller², and Penny A. Gowland^1
1The Sir Peter Mansfield Magnetic Resonance Centre, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, ²Nottingham Digestive Diseases Centre and NIHR Biomedical Research Unit, University of Nottingham, Nottingham, United Kingdom, ³Colworth Science Park, Unilever Discover, Sharnbrook, ⁴Unilever Discover, Vlaardingen, Netherlands

Improved knowledge of the relationship between the form of fat in a meal, the way the meal is handled by the body and the resulting sense of satiety is critical to understanding why modern processed foods are associated with increased obesity. This work aims to determine the effect of emulsion microstructure on the handling of fat by the GI tract, using model fat emulsion meals with different droplet sizes, MRI & MRS. Both stable forms of the emulsions (coarse+LBG & fine+LBG) lead to delayed gastric emptying due to increased sense of fullness and increased SBWC due to increased fat.

Tom Dresselaers¹, Christine Breynaert², Johan Cremer², Kristel Van Steen³, Clementine Perrier², Severine Vermeire⁴, Paul Rutgeerts⁴, Jan Ceuppens⁵, Gert Van Assche⁴, and Uwe Himmelreich^1
1Biomedical NMR Unit / MoSAIC, K.U.Leuven, Leuven, Leuven, Belgium, ²Division of gastroenterology, KULeuven, Leuven, Belgium, ³System and Modeling Unit, Montefiore Institute, Liege, Belgium, ⁴Department of Gastroenterology, University Hospital Gasthuisberg, ⁵Experimental immunology, K.U.Leuven

Most experimental animal models of inflammatory bowel diseases (IBD) fail to accurately reflect the chronically relapsing inflammation underlying the complications of human Crohn’s disease. This study investigated whether repeated cycles of dextran sulfate sodium salt (DSS) adequately reflect the effects of chronic transmural healing compared to the acute murine (DSS) colitis model with recovery. The in vivo T2 relaxometry showed significant differences between the first and second cycle of DSS. This difference was also evident from histology and macroscopic scoring. T2 relaxometry may therfore be a promising non-invasive assessment method in IBD. This model also opens perspectives to study the effects of healing and fibrosis in Crohn’s disease.

Johannes M Froehlich^1,2, Nicole Graf³, Constantin von Weymarn¹, Christoph A Binkert¹, Klaus Hergan⁴, and Andreas Gutzeit^1,4
1Department of Radiology, Cantonal Hospital, Winterthur, Switzerland, ²Scientific Affairs, Guerbet, Zurich, Switzerland, ³Clinical Trials Center, Center for Clinical Research, University Hospital, Zurich, Switzerland, ⁴Department of Radiology, Paracelsus Medical University, Salzburg, Austria

Spasmolysis of the small bowel is crucial for high-quality imaging of the abdomen/pelvis. The aim of this prospective investigation was to evaluate the duration and effectiveness of aperistalsis achieved by glucagon(GLU/1mg) or hyoscine-N-butylbromide(HBB/40mg) administered intravenously(i.v.), intramuscularly(i.m.), or combined i.v./i.m.. Six volunteers underwent five separate MRI-examinations covering 60-90min. Onset of aperistalsis did not differ statistically in case of i.v. administration(65/85sec) ending after 21±12.3min/23.3±14min, respectively. In contrast, spasmolysis of i.m. HBB and glucagon started significantly later(p=0.001) with 5.2±1.83min/11.6±10.2min. Aperistalsis lasted for 17.7±23.4min/28.2±26.9min with greater inter-individual differences(p=0.012). The combined scheme provides a rapid onset(65sec), prolonged effect(31±10.7min) at the highest degree of aperistalsis.

Caroline L Hoad¹, Helen Parker², Nicola Hudders², Carolyn Costigan¹, Eleanor F Cox¹, Luca Marciani², Mark R Fox², and Penelope A Gowland^1
1Physics and Astronomy, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, ²Nottingham Digestive Diseases Centre, NIHR Biomedical Research Unit, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom

This study develops a clinically applicable protocol to assess gastric function using MRI. A 400ml doped nutrient meal was ingested by ten healthy volunteers and their stomachs imaged using an optimised TrueFISP sequence. Total gastric (TGV) and liquid only volumes (LGV) were measured by 3 observers using an intensity based image segmentation algorithm. These volume data were then fitted to a complex model of gastric emptying to parameterize the secretion, relaxation and emptying of the stomach. Coefficients of variance (CV) were determined for the volumes and found to below 5% for all volumes greater than 100 ml.

Marije P. van der Paardt¹, André M.J. Sprengers¹, Rolf M. Lamerichs^1,2, Aart J. Nederveen¹, and Jaap Stoker^1
1Department of Radiology, Academic Medical Center Amsterdam, Amsterdam, Netherlands, ²Philips, Eindhoven, Netherlands

This study presents bowel motility assessment with Continuously Tagged MR imaging. This technique employs conventional MR-tagging, modified for non-periodic motion, from which spectral information was extracted when the tag pattern was deformed by tissue motion. Spectral analysis for different frequencies was performed. This non-invasive, free breathing and automated technique detected changes in bowel motility in a group of ten healthy volunteers after administration of a spasmolytic agent. Both in lower and higher frequencies significant decrease in motility was observed.

Thomas G. Perkins^1,2, Jeremy L. VanTilburg³, Gwenael Herigault⁴, Ty Bremer³, and Shahid M. Hussain^1
1University of Nebraska Medical Center, Omaha, Nebraska, United States, ²Philips Healthcare, Cleveland, Ohio, United States, ³The Nebraska Medical Center, Omaha, Nebraska, United States, ⁴Philips Healthcare, Best, Netherlands

Parallel radiofrequency transmission (MTX) was recently introduced to address the standing wave artifacts present at 3.0 T by providing independent control over the RF frequency, phase, and amplitude of the transmit RF coil elements. This study explored how patient-specific B1 shimming can eliminate the patient-to-patient variations in the image quality of abdominal MRI at 3.0 T. 99 patients were evaluated using the same abdominal imaging protocol (53 without and 46 with MTX). A significant improvement in overall image quality and decreased patient-to-patient variability were realized with MTX. MTX will likely increase the accessibility and utilization of 3.0T for abdominal MRI.

Mustafa Rifaat Bashir¹, Brian Marshall Dale², Rajan Tilak Gupta¹, Jeffrey J Horvath¹, Daniel Tobias Boll¹, and Elmar Max Merkle^1
1Radiology, Duke University Medical Center, Durham, NC, United States, ²Siemens Medical Solutions, Cary, NC, United States

In MRI of the liver, prescan adjustments are often performed prior to running each pulse sequence. However, repeating adjustments lengthens scan time, and adjustment data can, in many cases, be carried forward from pulse sequence to pulse sequence. Minimizing prescan adjustments (especially repeated shimming) by fixing table position and allowing maximal adjustment tolerances can reduce total examination time without reducing image quality or the quality of quantitative MRI data.

Mariah Smith-Miloff¹, Thomas G. Perkins^1,2, Baojiang Chen³, Jeremy L. Van Tilburg⁴, John L. Gollan⁵, and Shahid M. Hussain^1
1Radiology, University of Nebraska Medical Center, Omaha, Nebraska, United States, ²Philips Healthcare, Cleveland, Ohio, United States, ³Biostatistics, University of Nebraska Medical Center, Omaha, Nebraska, United States, ⁴The Nebraska Medical Center, Omaha, Nebraska, United States, ⁵University of Nebraska Medical Center, Omaha, Nebraska, United States

The goal of this study, consisting of 207 patients, was to quantify the improvements that can be gained at 3.0T abdominal MRI with the application of parallel radiofrequency transmission (MTX) primarily by correcting standing wave artifacts, and whether the impact of MTX correlates with body habitus. Significant improvements in mean signal-to-noise and contrast-to-noise ratios in left liver were observed with the application of MTX at two separate anatomical locations. These improvements in SNR and CNR were also demonstrated to increase as the cross-sectional body area increased using analysis of variance and linear regression model analysis.

David H Gultekin¹, Nancy E Kemeny², Lawrence H Schwartz³, Mithat Gonen⁴, Michael I D'Angelica⁵, Peter J Allen⁵, Yuman Fong⁵, Leslie H Blumgart⁵, Ronald P DeMatteo⁵, and William R Jarnagin^5
1Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, ²Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY, United States,³Radiology, Columbia University, New York, NY, United States, ⁴Epidemiology-Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, ⁵Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY, United States

Age related changes in perfusion and vascular permeability characteristics of the liver tissue have been investigated using dynamic contrast enhanced magnetic resonance imaging (DCE-MRI). Correlation statistics are performed between the age and several DCE-MRI parameters for subsets of gender and type for a group of primary liver cancer patients.

Chansik An¹, Mi-Suk Park¹, Myeong-Jin Kim¹, Yeo-Eun Kim¹, Woo-Suk Chung¹, Hyae Min Jeon², and Ki-Whang Kim^1
1Diagnostic radiology, Yonsei University Health System, Seoul, Korea, ²Pathology, Yonsei University Health System, Seoul, Korea

The combination of signal intensities on diffusion-weighted imaging (DWI) and dynamic subtraction imaging shows a linear association with histopathologic grade of hepatocellular carcinoma (HCC). The more the positive findings shown by an HCC lesion (arterial enhancement on subtraction imaging and restricted diffusion on DWI), the higher the grade (p < .001). In predicting well-differentiated HCC, the positive predictive value is higher when the findings on DWI and subtraction imaging are considered together (100%, when a lesion shows no arterial enhancement and no restricted diffusion) than when they are considered separately (81%, no arterial enhancement; 74%, no restricted diffusion).

Thomas A Hope¹, Rizwan Aslam², Carlos U Corvera³, Alex Monto⁴, Judy Yee², and Benjamin M Yeh^2
1Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States, ²Radiology, SFVA, San Francisco, CA, United States, ³Surgery, UCSF, San Francisco, CA, United States, ⁴Gastroenterology, UCSF, San Francisco, CA, United States

We prospectively studied the utility of gadoxetate for the further evaluation of equivocal lesions on CT in patients with cirrhosis. We enrolled 25 patients who had indeterminate lesions on CT. These patients subsequently underwent liver MRI using gadoxetate within two weeks of the CT examination. 32 lesions in 25 patients were imaged. After the administration of Eovist, 13 lesions were downgraded, 11 lesions were upgraded and 8 lesions retained the same grade. In this interim report, gadoxetate appears to aid in the evaluation of indeterminate lesions. Additional follow-up needs to be performed, and goal enrollment is 50 patients.

Tetsuya Wakayama¹, Keizo Miyakoshi², Daisuke Nishiyama², Masahiro Okada³, Hiroyuki Kabasawa¹, Tatsuro Uto², and Takamichi Murakami^3
1Global Applied Science Laboratory, GE Healthcare, Hino, Tokyo, Japan, ²Department of Radiological Technology, Kinki University Hospital, Japan, ³Department of Radiology, Kinki University Faculty of Medicine, Japan

A novel approach to three dimensionally measure T1 value of liver with IR-based multiple breath-holding acquisitions was developed and demonstrated in this study. The phantom validation revealed that 3D T1map developed here could provide acceptable accuracy of T1 with larger volume coverage and less scan time, compared with 2D T1map acquired by conventional 2D IR-FSE. In volunteer examination, 3D T1map was successfully obtained from liver. This approach can be expected to three dimensionally evaluate T1 of the liver with clinically acceptable scan time.

Kengo Yoshimitsu¹, Kimiyo Inoue², Wirana Angthong², Ritsuko Fujimtsu², Mikiko Shimakura², Atsushi Takemura³, Makoto Obara³, and Marc van Cauteren^3
1Radiology, Fukuoka University, Fukuoka, Fukuoka, Japan, ²Fukuoka University, Japan, ³Philips Medical Systems, Japan

T2-weighted VISTA for liver imaging was optimized with RFA 30, TSE factor 100, and radial order turbo direction. In clinical situation, VISTA with these parameters and respiratory navigation provided better T2-weighted images with high resolution and black blood as compared to breath-hold 2DTSE in gadoxetate-enhanced MR protocol, without extending the whole examination time. Because of its susceptibility to motion, however, signal reduction may occur in ascitic fluid or pleural effusion, and therefore concurrent use of TSE may be recommended.

Yi-Xiang Wang¹, Feng Zhao¹, Vincent Wai Sun Wong², Jing Yuan¹, Kin Ming Kwong¹, and Henry Lik Yuen Chan^2
1Dept Imaging & Interventional Radiology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, ²Dept Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong

We carried out liver T1rho MR imaging in 10 patients with liver cirrhosis. T1rho value inhomogeneity was noted in the liver of the patients, with T1rho value of right robe tended to be higher than that of left robe. To quantify liver T1rho value, ROIs were manually placed on right robe parenchyma region of each slice’s T1rho maps, excluding observable artifacts and blood vessels. Nine patients completed the study. With T1rho value measured from the right liver lobes, the mean value (± SD) was 51.1±8.1 millisecond, higher than the reported T1rho mean value of 43.0±2.2 millisecond in healthy volunteers.

Shigeyoshi Saito¹, Yuki Moriyama¹, Shuichiro Kobayashi¹, Ryota Ogihara¹, Daichi Koto¹, Akihiko Kitamura¹, Taro Matsushita¹, Motoko Nishiura¹, and Kenya Murase^1
1Department of Medical Physics and Engineering, Osaka University, Suita, Osaka, Japan

Our purpose of this study was to evaluate thioacetamide (TAA)-induced acute liver injury in rats using an empirical mathematical model (EMM) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA). DCE-MRI studies were performed using Gd-EOB-DTPA, 48 hours after TAA or saline injection. We calculated the rate of contrast uptake, the rate of contrast washout, the elimination half-life of relative enhancement (RE), the maximum RE, and the time to (REmax) (Tmax) from time-signal intensity curves using EMM. The EMM is useful for the assessment of TAA-induced rat acute liver injury using DCE-MRI with Gd-EOB-DTPA.

Bobby Kalb¹, David Becker-Weidman², Surya Chundru¹, James Costello¹, Puneet Sharma¹, Khalil Salman¹, Hina Arif¹, and Diego R Martin^1
1Radiology, University of Arizona, College of Medicine, Tucson, AZ, United States, ²Radiology, Emory University Department of Medicine, Atlanta, GA, United States

Reduction of post-transplant recurrence of hepatocellular carcinoma (HCC) is optimized by strict pre-transplant tumor staging (Milan criteria); however post-transplant tumor recurrence still occurs in up to 10% of patients with optimal preoperative staging. Imaging methodologies that are better able to predict recurrence risk of HCC from pretransplant imaging would be valuable in the triage of donor organs. Our study investigates potential imaging features on MRI that may provide added prognostic information regarding the biological behaviour of HCC, with the aim to better predict posttransplant recurrence.

Arthur Wunderlich¹, Holger Cario², and Markus Juchems^1
1Diagnostic and Interventional Radiology, Univ.-Clinic Ulm, Ulm, Baden-Württemberg, Germany, ²Childrens Hospital, Univ.-Clinic Ulm, Ulm, Baden-Württemberg, Germany

To compare liver iron content (LIC) determined by different established MRI methods, we investigated 198 patients with protocols according to published methods, three using gradient echo (GRE) sequences and one working with spin echo (SE). The methods correlate moderately with r=0.90. Weakpoints are the bad performance of one GRE method near its upper limit and sensitivity to liver steatosis of the GRE method addressing high LIC. The latter is most likely the cause for reduced correlation of SE vs. GRE for high LICs. Although GRE generally tends to overestimate LIC, both methods are suitable for decisions concerning patient management.

Arthur Wunderlich¹, Holger Cario², and Markus Juchems^1
1Diagnostic and Interventional Radiology, Univ.-Clinic Ulm, Ulm, Baden-Württemberg, Germany, ²Childrens Hospital, Univ.-Clinic Ulm, Ulm, Baden-Württemberg, Germany

To establish an MR method for determining liver iron content (LIC), we investigated 173 patients with protocols according to three published methods, two using gradient echo (GRE) sequences and one working with spin echo (SE). The latter served as reference. Since deviations between calculated LIC values occurred, we performed multiple linear regressions on signal intensity values of different GRE protocols to get an improved relation. We showed that in our patients for LIC values up to 300 µmol/g a single GRE measurement gives results with good correlation to values determined with SE. For higher LIC, more GRE protocols are needed.

Feng Zhao¹, Min Deng¹, Jing Yuan¹, Queenie Chan², Jun Yu³, and Yi-Xiang Wang^1
1Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, ²Philips Healthcare, Hong Kong, ³Department of Medicine and therapeutics, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong

Liver T1rho relaxation became prolonged after bile duct ligation-induced liver injury in rats has been reported. In this study, the liver of male Sprague-Dawley rats treated with carbon tetrachloride (CCl4) were scanned by T1rho and T2 weighted imaging at baseline, 2 days, 2 weeks, 4 weeks, 6 weeks post CCl4 injection. Liver T1¦Ñ value increased slightly on day 2, increased further during the following weeks and was the highest at week 6 post insults. Relative liver signal intensity change on T2 weighted images followed a different time course.

Jeong Min Lee¹, In Pyung Hwang², Joon Koo Han², Berthold Kiefer³, Andre de Oliverira³, Mun Young Paek³, and Byung Ihn Choi^2
1Radiology, Seoul National University Hospital, Seoul, Seoul, Korea, ²Seoul National University Hospital, ³Siemens Healthcare

Combined use of the T2*-corrected CSI and BH 1H-MRS allowed a rapid and noninvasive diagnosis of HS in potential living liver donors; it can also help to avoid unnecessary biopsies in these patients.

Tedros Bezabeh¹, Omkar B Ijare¹, Nils Albiin², Annika Bergquist³, Urban Arnelo⁴, Matthias Löhr³, and Ian CP Smith^1
1MR Research and Development, National Research Council Institute for Biodiagnostics, Winnipeg, MB, Canada, ²Medical Imaging and Technology, Karolinska Institutet, Stockholm, Sweden, ³Gastroenterology and Hepatology, Karolinska Institutet, Stockholm, Sweden, ⁴Surgery, Karolinska Institutet, Stockholm, Sweden

Tight junctions (TJs) are associated with hepatocytes and cholangiocytes. Specifically, TJs associated with hepatocytes are concentrated around bile canaliculi, and serve as barrier to keep bile in bile canaliculi away from blood-circulation. Alterations in TJs have been observed in various chronic cholestatic diseases, resulting in increased paracellular permeability leading to regurgitation of bile from biliary tract. In this study, we have observed that ¹H MRS pattern of bile from a few cholestatic patients resembled to that of serum. We hypothesize that this anomaly could be due to alterations in TJs and regurgitation of blood constituents into bile.

Tsutomu Tamada¹, Akihiko Kanki¹, Tomohiro Sato¹, Atsushi Higaki¹, Yasufumi Noda¹, Akira Yamamoto¹, Hiroki Higashi¹, and Katsuyoshi Ito^1
1Radiology, Kawasaki Medical School, Kurashiki City, Okayama, Japan

We evaluated the physiological accumulation of bile in gallbladder using DCE-MRC obtained with Gd-EOB-DTPA. As the results, Twenty-seven of 75 patients (36%) were delayed type (Visualization of Gd-EOB-DTPA in the end of the common bile duct is earlier than that of gallbladder), and remaining 48 (64%) were orthodromic type (Visualization of Gd-EOB-DTPA in the gallbladder is earlier than that of end of the common bile duct). The delay of the bile accumulation in the gallbladder is associated with T1 hyperintense bile or sludge of gallbladder, indicating the increase of viscosity and pressure in the gallbladder.

Keizo Tanitame¹, Yuko Nakamura¹, Yoko Kaichi¹, Chihiro Tani¹, Yukiko Honda¹, Miyuki Takasu¹, and Kazuo Awai^1
1Diagnostic Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Hiroshima, Japan

Problem To compare the ADC values of AIP and pancreatic carcinoma and investigate their usefulness in IgG4-related AIP during steroid therapy. Methods ADC values were compared among 10 patients with IgG4-related AIP, 7 with IgG4-negative AIP, 27 with carcinoma. In 6 patients with IgG4-related AIP ADC values were followed during steroid therapy. Results The ADC values were significantly lower in IgG4-related and -negative AIP than carcinoma (p<0.01, each). ADC values increased during the therapy in all patients with IgG4-related AIP. Conclusion ADC value was useful for differentiating between AIP and pancreatic carcinoma and for assessing the effects of steroid therapy.

Eleanor F Cox¹, Janet K Smith², John Simpson², and Susan T Francis^1
1SPMMRC, School of Physics & Astronomy, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, ²Nottingham Digestive Diseases Centre BRU, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom

Alterations in pancreatic blood flow have been implicated in pancreatic inflammation and pain. However, there are few methods to assess pancreatic blood flow and these are generally invasive, using ionising radiation or intravenous contrast media, limiting repeat measures. Here, we use secretin stimulation to alter blood flow. We repeatedly measure pancreatic tissue perfusion using respiratory-triggered arterial spin labelling, and vessel blood flow (superior mesenteric SMA, gastroduodenal GDA, hepatic, splenic arteries), using phase contrast MRI, before and at 10 minute intervals following secretin administration. We show pancreatic tissue perfusion, SMA flow, and GDA flow, were all significantly increased following secretin administration.

Kazuya Yasokawa¹, Katsuyoshi Ito¹, Tsutomu Tamada¹, Teruyuki Torigoe¹, Akihiko Kanki¹, Yasufumi Noda¹, and Koji Yoshida^2
1Radiology, Kawasaki Medical School, Kurashiki, Okayama, Japan, ²Kawasaki Medical School, Kurashiki, Okayama, Japan

This study evaluated non-invasively the alteration in the secretory flow of pancreatic juice in patients with IPMNs of the pancreas by using cine dynamic MRCP with spatially labeled IR pulse in comparison with the physiological flow of pancreatic juice in normal subjects. The flow of the pancreatic juice was impaired or became slow in patients with IPMNs, probably due to mixture of mucinous component from IPMNs in the pancreatic duct. It would be important to be aware of the alteration in the secretory flow of the pancreatic juice in patients with IPMNs even though pancreatic exocrine function is normal.

Roshan Livingstone¹, Paul Begovatz¹, Sabine Link¹, Bettina Nowotny¹, Birgit Klueppelholz², Guido Giani², Juergen Bunke³, Michael Roden^1,4, and Jong-Hee Hwang^1
1Institute of Clinical Diabetology, German Diabetes Center, Düsseldorf, Germany, ²Institute for Biometry and Epidemiology, German Diabetes Center, Düsseldorf, Germany,³Philips Healthcare, Hamburg, Germany, ⁴Department of Metabolic Diseases, University Clinics, Heinrich Heine University, Düsseldorf, Germany

1H-MRS is considered the gold standard for liver fat measurements, however, it is unclear whether H-1 MRS is more accurate for the pancreas than DIXON methods. A flexible 2-point mDIXON method (TE1/TE2 = 1.12/2.0 ms) was compared to 1H-MRS for fat fraction of the liver and pancreas in 19 volunteers. Values of hepatic fat fraction by mDIXON and 1H-MRS correlated well with each other (r = 0.96, p<0.00001), however, in the pancreas a correlation of (r=0.66, p<0.001) was found, which was probably attributed to differences in the amount and distribution of fat between the two organs.

Suresh Anand Sadananthan^1,2, Eric Khoo Yin Hao³, Melvin K-S Leow^1,4, ChinMeng Khoo³, Lee Yung Seng^1,5, Peter Gluckman¹, Tai E Shyong^1,3, and S. Sendhil Velan^1,6
1Singapore Institute for Clinical Sciences, A*STAR, Singapore, ²Dept. of Obstetrics & Gynaecology, National University of Singapore, Singapore, ³Dept. of Medicine, National University of Singapore, ⁴Dept. of Endocrinology, Tan Tock Seng Hospital, Singapore, ⁵Dept. of Pediatrics, National University of Singapore, ⁶Singapore Bioimaging Consortium, A*STAR, Singapore

MRI and MRS allow for the investigation of changes in fat metabolism by exercise/dietary intervention in liver, muscle and abdominal fat (subcutaneous (SAT) and visceral (VAT)). In this study, we investigated the changes in fat distribution pre- and post-weight loss intervention in overweight Chinese men. The 16-week weight loss program consisted of three 90-min exercise sessions per week and a diet comprising of a caloric deficit of upto 1000 kcal. The results showed significant gain in fat depots post-weight loss except for IMCL. Further, the increase in SAT, VAT and %body-fat revealed significant correlations with the increase in insulin sensitivity.

Stefan Haneder¹, Simon Konstandin², John Morelli³, Lothar R Schad², Stefan O Schoenberg¹, and Henrik J Michaely^1
1Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Mannheim, Baden-Württemberg, Germany, ²Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Baden-Württemberg, Germany, ³Scott and White Memorial Hospital and Clinic – Texas A&M University Health Sciences Center, Temple, Texas, United States

Two new approaches are introduced and evaluated for the (semi-)quantitative assessment of the renal sodium content with 23Na MR imaging before and after a water load. One approach used the cerebrospinal fluid as internal reference for the cortico-medullary 23Na gradient. The second approach quantified the cortico-medullary 23Na gradient with reduced numbers of slices. Both methods are compared to the gold standard – quantification with complete data sets and external references. Both approaches showed non-significant differences compared to the gold standard and seem to be a feasible and faster alternative for potential clinical application.

Huaiqiang Sun^1,2, Lan Lu², David L Wilson¹, Katherine M Dell^3,4, and Chris A Flask^1,2
1Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, ²Radiology, Case Western Reserve University, Cleveland, OH, United States,³Pediatrics, Case Western Reserve University, and Rainbow Babies and Children’s Hospital, Cleveland, OH, United States, ⁴CWRU Center for the Study of Kidney Disease and Biology, Case Western Reserve University, Cleveland, OH, United States

Autosomal Recessive Polycystic Kidney Disease (ARPKD) is a multiorgan disease manifest as increasing renal cysts as well as hepatobiliary dilatation and congenital hepatic fibrosis. We are exploring the potential of T₂ relaxation assessments to assess renal cystic burden and hepatobiliary dilatation in the PCK rat model of ARPKD. In this study, we demonstrated that removal of early echoes (TE = 10-30ms) from the T₂ calculation can reduce the biexponential nature of the T₂ decay curve likely caused by tissue perfusion. As a result, these T₂ estimations may provide accurate estimates of hepatobiliary dilatation as well as renal cystic burden.

Alvin C Silva¹, Annelise M Silva², Roger C Grimm³, Kevin J Glaser³, Amy K Hara¹, and Richard L Ehman^3
1Radiology, Mayo Clinic Arizona, Scottsdale, Arizona, United States, ²Xavier, Scottsdale, Arizona, United States, ³Radiology, Mayo Clinic Rochester, Rochester, Minnesota, United States

MR Elastography is a promising, noninvasive technique for discriminating normal from diseased liver, including fibrosis stage. With the introduction of a new inversion algorithm (MMDI) and confidence mask, suggested published threshold values in this regard may have to be modified. The purpose of this study is to compare calculated mean shear hepatic stiffness calculations (kPa) between the two inversions algorithms and assess inter- & intraobserver variability between two measurement techniques (ie, confidence threshold mask versus free-hand ROI).

Surya Chundru¹, Diego Martin¹, Puneet Sharma¹, Ryan Pathak², Amanda Cox², Lance W Farr², Tim James², and Peter Jezzard^3
1University Medical Center, University of Arizona, Tucson, Arizona, United States, ²Acuitas Medical, Swansea, United Kingdom, ³Department of Clinical Neurology, University of Oxford, Oxford

Non-invasive measurement of liver fibrosis in chronic liver disease (CLD) remains an unmet clinical need. We have developed a Fine Texture Analysis technique (wavelength analysis of fine texture wavelengths below the resolution limit of clinical MRI) and applied this technique to specially acquired MR data to evaluate the capacity for detecting liver fibrosis (LF). LF should alter the normal background liver texture to produce gradient stages of signature wavelength distributions as the coarser fibrotic texture replaces the finer vascular normal texture. Our results show good correlation between clinical assessment of disease stage and spectral features, supporting our hypothesis.

Eleanor F Cox¹, Abeed H Chowdhury², Dileep N Lobo², and Susan T Francis^1
1SPMMRC, School of Physics & Astronomy, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, ²Nottingham Digestive Diseases Centre BRU, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom

Infusions of large volumes of saline (an unbalanced crystalloid) can cause hyperchloremic acidosis, which has previously been shown to reduce renal blood flow in canine models. We predicted that a balanced crystalloid with an electrolyte composition closer to human blood plasma would not produce this effect on renal blood flow and perfusion. Following 2 litre infusions over 60 minutes in 12 healthy males, the renal artery blood flow velocity and renal cortical perfusion were significantly reduced following the unbalanced crystalloid, whilst no significant change in flow or perfusion were found for the balanced crystalloid.

Sung Il Hwang¹, Hak Jong Lee², and Ho Jun Chin^2
1Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, Korea, ²Seoul National University Bundang Hospital

Renal BOLD MRI can be efficiently performed with 3.0 T MRI in patients. Renal medullary hypoxia is decreased in patients with acute renal failure patients.

Stefan Haneder¹, Judit Boda-Heggemann², Simon Konstandin³, Lothar R Schad³, Frederik Wenz², Frank Lohr², Stefan O Schoenberg¹, and Henrik J Michaely^1
1Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Mannheim, Baden-Württemberg, Germany, ²Department of Radiation Oncology, University Medical Center Mannheim, Mannheim, Baden-Württemberg, Germany, ³Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Baden-Württemberg, Germany

Conventional 3-dimensional conformal radiotherapy (3D-CRT) after gastric cancer results in ablative doses to the cranial part of the left kidney, while image-guided intensity-modulated radiotherapy (IG-IMRT) provides improved kidney sparing. Functional magnetic resonance imaging at 3.0T including BOLD, DWI and 23Na-imaging was used to evaluate renal status after radiotherapy with 3D-CRT or IG-IMRT. Marked morphological/functional effects were observed in high-dose areas (3DCRT) while no alteration in kidney function was observed in IG-IMRT patients who received lower doses of radiation. Functional MRI at 3.0T seems feasible for investigation of post-radiotherapeutic renal changes.

Xiufeng Li¹, Carl Snyder¹, Pierre-Francois Van de Moortele¹, Kamil Ugurbil¹, and Gregory J. Metzger^1
1Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States

Arterial spin labeling imaging, as a non-invasive and non-contrast enhanced approach, is very suitable for longitudinal evaluation of kidney function after transplantation, and can significantly benefit patients with renal dysfunction or other contraindications to the use of MR contrast-agent. The increased longitudinal relaxation time of the blood at ultrahigh field (UHF) can improve non-contrast enhanced perfusion imaging using ASL. To evaluate the technical challenges and potential benefits of performing renal ASL perfusion studies at UHF, the FAIR technique was implemented and used to study kidney perfusion in normal healthy controls. In this article, our initial experience and results are presented.

Yasufumi Noda¹, Akihiko Kanki², Tsutomu Tamada², Akira Yamamoto², Atsushi Higaki², Tomohiro Sato², Daigo Tanimoto², and Katsuyoshi Ito^2
1KAWASAKI MEDICAL SCHOOL, KURASHIKI, OKAYAMA, Japan, ²KAWASAKI MEDICAL SCHOOL

Age-related change in renal corticomedullary differentiation was evaluated by means of non-contrast-enhanced SSFP MR imaging with Time-SLIP. In normal kidney, non-contrast-enhanced SSFP MR imaging with Time-SLIP can be used to assess the renal corticomedullary differentiation and cortical thickness without influence of the aging although optimal TI value for the best visualization of renal corticomedullary junction should be shortened with aging. This fact suggested that SSFP MR imaging with Time-SLIP has a potential to evaluate the renal function based on renal cortical thickness or volume without considering an age-related change.

Eito Kozawa¹, Tsutomu Inoue², kaiji Inoue³, Hiromichi Suzuki², and Junji Tanaka^4
1Diagnosis Imaging, Saitama Medical University, International Medical Center, Hidaka-shi, Saitama, Japan, ²Nephrology, Saitama Medical University, Japan, ³radiology, Saitama Medical University, Japan, ⁴Radiology, Saitama Medical University, Japan

Renal BOLD MRI provides comprehensive information including changes in intrarenal oxygenation.

Jing Wang¹, Yudong Zhang², Xiaoying Wang^1,2, Jue Zhang^1,3, and Jing Fang^1,3
1Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, ²Department of Radiology, Peking University First Hospital, Beijing, China, ³College of Engineering, Peking University, Beijing, China

In this study, short-term effects of furosemide on renal perfusion were investigated by using FAIR-ASL at 3T MR. Baseline and post ASL images were acquired on healthy subjects before and after furosemide administration to measure the renal hemodynamic response. Furosemide produced a remarkable reduction in medullar RBF, while cortical and global RBF changes did not reach a significant level. Furosemide administration is associated with a prominent decrease in the medullar blood perfusion, but its hemodynamic effects on the renal cortex still need further study, while ASL-MRI provides an alternative way to noninvasively monitor changes in renal function.

Marla Shaver¹, and Michael Noseworthy^2
1School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada, ²School of Biomedical Engineering, Electrical and Computer Engineering, McMaster University, Hamilton, Ontario, Canada

In this study, real-time BOLD data from healthy kidneys was analyzed to determine whether signal variations are fractal, and if so whether they can be characterized as fractional Gaussian noise (fGn) or fractional Brownian motion (fBm). Images were acquired using a T2* weighted GRE EPI sequence. Subjects were instructed to breath quietly during image acquisition. Rapidly acquired BOLD data from both kidney cortex and medulla behave fractally, where the majority of the data is characterized as fGn.

Neil Peter Jerome¹, Matthew Orton¹, James d'Arcy¹, David J Collins¹, Dow-Mu Koh², and Martin O Leach^1
1CRUK-EPSRC Cancer Imaging Centre, The Institute of Cancer Research, Sutton, Surrey, United Kingdom, ²Department of Radiology, Royal Marsden Hospital, Sutton, Surrey, United Kingdom

Discussions about the optimum breathing modality for acquiring abdominal diffusion-weighted MR images include consideration of navigator-controlled acquisition to reduce motion blurring, but this is dependent on repeatability of respiratory cycle and is inevitably time-inefficient. Adopting a free-breathing strategy allows greater averaging for the same acquisition time; we show that fitted pefusion-insensitive ADC parameters from the kidneys of a volunteer cohort are not significantly different between navigator-controlled and free-breathing modalities. Global statistics are reported, as well as for renal cortex and pyramid ROIs, and distibutions of ADCs and of signal intensities at each b-value are shown to be not significantly different.

Florian Lietzmann¹, Frank G. Zoellner¹, Tanja Gaa¹, Ulrike I. Attenberger², and Lothar R. Schad^1
1Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Germany, ²University Medical Centre Mannheim, Institute of Clinical Radiology and Nuclear Medicine, Mannheim, Germany

In recent years blood oxygen level dependent (BOLD) MRI has gained more importance in the entire field of MRI.Therefore we performed a clinical study with 4 healthy volunteers and investigated if the signal changes in the kidney due to a water intake of the volunteers could satisfactorily being followed and if our optimized sequences with high parallel imaging acceleration factors can be used for quick renal BOLD-MRI. We investigated three different sequences each with a different resolution and imaging time. After T2* mapping in the post processing step and a ROI-readout, the time courses showed the expected signal changes after the water intake independent of the used sequence.

Frank G Zoellner^1,2, Sheng Li^1,3, Andreas D Merrem¹, Jarle Roervik^2,4, Arvid Lundervold^4,5, and Lothar R Schad^1
1Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Germany, ²Section for Radiology, Dept. of Surgical Sciences, University of Bergen, Bergen, Norway,³Institute of Knowledge Based Engineering, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China, ⁴Dept. of Radiology, Haukeland University Hospital, Bergen, Norway, ⁵Dept. of Biomedicine, University of Bergen, Bergen, Norway

Correct determination (segmentation) of the renal compartments within the images is crucial to obtain i.e. whole kidney GFR via pharmacokinetic modelling. We propose a wavelet-based segmentation method to group the voxel time courses and thereby segment the renal compartments. This method was applied to DCE-MRI data sets of 4 healthy volunteers and 3 patients. On average, the renal cortex could be segmented at 88%, the medulla at 91%, and the pelvis at 98% accuracy. Time intensity curves showed well known characteristics of perfusion time curves for the respective compartments. In conclusion, wavelet based clustering of DCE-MRI of kidney is feasible.

Martin P Smith¹, Olga Brook¹, Long Ngo², Neil Rofsky³, and Ivan Pedrosa^4
1Radiology, BIDMC, Boston, MA, United States, ²Medicine, BIDMC, Boston, MA, United States, ³Radiology, UT Southwestern, Dallas, MA, United States, ⁴Radiology, UT Southwestern, Dallas, TX, United States

Quantitative methods can be used to diagnose accurately solid enhancing renal tumors with contrast-enhanced MRI that works with image subtraction and comparing SI measurements between unenhanced and contrast-enhanced images.

Peter Vermathen¹, Aurelia Rusch-Kölbener¹, Tania Bühler¹, Tobias Binser¹, Harriet C Thoeny², Felix J Frey³, Chris Boesch¹, and Ute Eisenberger^3
1Depts Clinical Research and Radiology, University Bern, Bern, Switzerland, ²DRNN, Inselspital Bern, Bern, Switzerland, ³Dept. Nephrology and Hypertension, Inselspital Bern, Bern, Switzerland

The effect of unilateral nephrectomy on the sizes of the remaining kidneys was investigated longitudinally over 1 year in 13 living renal donors and the sizes of the explanted kidneys were followed up in the corresponding recipients. The remaining kidneys of donors increased significantly by ~15% early after explantation and continued to increase slightly until 1 year. Renal sizes of allografts correlated significantly with those obtained in the same kidneys before transplantation in donors. After transplantation the allograft sizes remained constant. Conclusion: The remaining kidney of donors exhibits compensatory size growth to overcome renal mass reduction due to unilateral nephrectomy.

Akihiko Kanki¹, Katsuyoshi Ito¹, Tsutomu Tamada¹, Yasufumi Noda¹, Kazuya Yasokawa¹, and Tomohiro Sato^1
1Radiology, Kawasaki Medical School, Kurashiki, Okayama, Japan

This study compared the two different MR sequences, fast asymmetric spin echo (FASE) and steady-state free-precession (SSFP) combined with time-spatial labeling inversion pulse (Time-SLIP), for the better visualization of corticomedullary differentiation in the normal kidney. Both FASE and SSFP MR imaging with Time-SLIP can be used to visualize the renal corticomedullary differentiation in normal kidneys without using contrast agents. SSFP sequence with Time-SLIP may be preferable for the measurement of renal cortical thickness or volume because of good visualization of corticomedullary junction and high image quality although FASE sequence with Time-SLIP had high corticomedullary contrast ratio.

Masahiro Umeda¹, Toshihiro Higuchi², Yuki Mori³, Yoshichika Yoshioka⁴, Yasuharu Watanabe¹, Yuko Kawai¹, Tomokazu Murase², and Chuzo Tanaka^2
1Medical Informatics, Meiji University of Integrative Medcine, Nanantanshi, Kyoto, Japan, ²Neurosurgery, Meiji University of Integrative Medcine, Nanantanshi, Kyoto, Japan,³Immunology Frontier Center, Osaka University, Suita, Osaka, Japan, ⁴Immunology Frontier Research Center, Osaka University, Suita, Osaka, Japan

The renal ADCs with high b values (100 - 800 s/mm²) were investigated during the cardiac cycle. The average ADC of the renal medulla was higher than that of cortex ( P < 0.01). However a maximum renal arterial flow occurred at 60 ms after R-wave during the cardiac cycle, the changes of ADC with high b value showed no peak at the same time . The renal ADC with high b values was less influenced by renal blood flow.

Mengyu Liu¹, Huadan Xue², Xuan Wang², Yuan Liu², and Zhengyu Jin^2
1PLA general hospital, Beijing, Beijing, China, ²Peking Union Medical College Hospital

26 middle-aged healthy volunteers were enrolled in this study to receive three-dimensional (3D) non-contrast enhanced MR angiography with a time-spatial labeling inversion pulse (Time-SLIP) of renal artery. All volunteers received coronal orientations with 3 different black blood inversion time(900, 1200, 1500 ms). Relative signal intensity (rSI) of renal artery, visibility score (Rank 1-4) in 3 segments of the renal artery and the numbers of the branches were evaluated as indexes of the Time-SLIP sequence image quality. We get the conclusion that a black blood inversion time of 1200ms was considered to be the optimal choice for this purpose.

Jing Wang¹, Yudong Zhang², Yue Zhang³, Xiaoying Wang^1,2, Jue Zhang^1,3, and Jing Fang^1,3
1Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, ²Department of Radiology, Peking University First Hospital, Beijing, China, ³College of Engineering, Peking University, Beijing, China

This study developed an approach for renal perfusion and glomerular filtration rate mapping based on the combination of pulsed arterial spin labeling technique and a spin-echo EPI with multiple TEs sequence on clinical 3T MR. Each of ten healthy young subjects accepted 12 breath-hold ASL scans for different TEs acquisition. Based on the proposed method, the RBF, blood R2* and GFR maps were obtained simultaneously. We hope that this MR technique can be combined with other functional methods to provide a complete noninvasive assessment of renal status in a single examination.

Neil Peter Jerome¹, Jessica K R Boult¹, Matthew Orton¹, James d'Arcy¹, David J Collins¹, Dow-Mu Koh², and Simon P Robinson^1
1CRUK-EPSRC Cancer Imaging Centre, The Institute of Cancer Research, Sutton, Surrey, United Kingdom, ²Department of Radiology, Royal Marsden Hospital, Sutton, Surrey, United Kingdom

Preclinical studies are increasingly performed on clinical systems, using superior hardware and conferring greater clinical relevance. Limitations in signal, leading to lack of spatial resolution or insufficient signal for fitting decay curves, can be mitigated by use of an extremity loop coil with a standard head array for parallel acquisition. We demonstrate observation of time-dependent changes in T₂* from normal rat kidney following administration of vasomodulators such as hydralazine, furosemide, and angiotensin II, and show the potential of such a set-up to probe homeostatic response to vasomodulation, with potential for extrapolation to renal disease and pathophysiological studies.

Katherine Frances Holliday^1,2, Geoffrey J M Parker^1,2, Mark Dobbs^1,2, and Josephine Helen Naish^1,2
1Imaging Sciences, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom, ²Biomedical Imaging Institute, Manchester, United Kingdom

OE-MRI uses an oxygen gas challenge to investigate tissue oxygenation by measuring a change in signal or T₁; literature suggests this challenge may cause a reduction in blood flow. This study aimed to investigate the effect of such a gas challenge on renal blood flow using ASL. 10 healthy subjects were recruited. Across all subjects no significant difference was found in blood flow in the renal cortex. However if we ignore blood T₁ changes there is an apparent significant decrease in flow. It is therefore important to consider blood T₁ changes when using ASL to measure the effect of oxygen.

Haiyi Wang¹, Huiyi Ye¹, Jia Wang¹, Xu Zhang², Aitao Guo³, Yingwei Wang¹, and Xinkun Wang^1
1Department of Radiology, Chinese PLA General Hospital, Beijing, China, ²Department of Urology, Chinese PLA General Hospital, Beijing, China, ³Department of Pathology, Chinese PLA General Hospital, Beijing, China

Diffusion-weighted imaging (DWI) has become an established method for abdominal imaging. The kidney is a particularly interesting organ to study with DWI. Conventional DWI requires breath-hold during scanning, which sometimes cannot be realized for patients with breath-hold difficulty. This study compares the respiratory-triggered, free-breathing and breath-hold DWI of renal lesions, and the conclusion is drawn that respiratory-triggered and free-breathing DWI can be appropriate sequences for evaluation of renal lesions without any compromise in the calculated ADC values, and free-breathing DWI can display better image quality.

Mengyu Liu¹, Huadan Xue², Xuan Wang², Min Sheng², Yuan Liu², and Zhengyu Jin^2
1PLA general hospital, Beijing, Beijing, China, ²Peking Union Medical College Hospital

25 patients were enrolled in this study to evaluate the renal anatomy and renal stenosis in three-dimensional (3D) non-contrast enhanced MR angiography with a time-spatial labeling inversion pulse (Time-SLIP) compared with computer tomography angiography ( CTA). All subjects received both coronal and axial views of MRA with a Time-SLIP. The variants of renal artery were same and the evaluation of renal artery stenosis were consistent of the two image modalities. The discrepancy between them may related to the calcification of the renal artery and the change of the hemodynamic of the stenosis.

Peter Vermathen¹, Huanxiang Lu², Tobias Binser¹, Ute Eisenberger³, Chris Boesch¹, and Mauricio Reyes^2
1Depts Clinical Research and Radiology, University Bern, Bern, Switzerland, ²Institute for Surgical Technology and Biomechanics, University Bern, Bern, Switzerland, ³Dept. Nephrology and Hypertension, Inselspital Bern, Bern, Switzerland

Physiological motion caused by respiration leads to image artifacts in abdominal DTI. Even in respiratory triggered scans residual motion remains. The aim of this study on 12 subjects was to employ non-rigid image registration of individual echo planar DTI images of human kidneys, which are virtually free of motion artifacts, and to compare the variability of the determined diffusion parameters and image blurring with the standard processing. Significantly lower signal variabilities and standard deviations of determined diffusion parameters were obtained from co-registered images, clearly demonstrating the benefit of performing co-registration of individual EP-images in DTI measurements of the kidney.

Andrew B Gill¹, Gayathri D S Anandappa², Andrew N Priest¹, Andrew J Patterson¹, Martin J Graves¹, Ilse Joubert¹, Louise M Cookson³, Kate M Fife², Philip S Murphy³, Duncan B Richards³, Evis Sala¹, Tim Eisen², Duncan I Jodrell², and David J Lomas^1
1Radiology, Addenbrooke's Hospital & University of Cambridge, Cambridge, United Kingdom, ²Oncology, Addenbrooke's Hospital & University of Cambridge, ³GlaxoSmithKline, United Kingdom

This study investigated DCE-MRI indices as early indicators of the activity of the antiangiogenic drug bevacizumab when used in patients with metastatic renal cell carcinoma. Two base-line and two post-treatment examinations were performed on six patients. DCE-MRI data was analysed using an ‘extended Tofts’ kinetic model with a model AIF to produce parameter maps which were then analysed to yield tumour medians. Significant reductions, compared to the mean of the base-line levels, were found in K^trans and v_pin tumours 3 days after treatment. IAUGC90 values showed a significant decrease both 4 hours after treatment and 3 days after treatment.

Stephanie Donaldson¹, Bernadette Carrington², Suzanne Bonington², Richard Cowan³, Jeanette Lyons³, and David Buckley^4
1Christie Medical Physics and Engineering, The Christie, Manchester, Greater Manchester, United Kingdom, ²Department of Radiology, The Christie, Manchester, United Kingdom, ³Department of Clinical Oncology, The Christie, Manchester, United Kingdom, ⁴Division of Medical Physics, University of Leeds, Leeds, United Kingdom

Treatment of bladder cancer with chemotherapy and radiotherapy results in inflammation which mimics residual tumour on conventional MR images. Dynamic contrast-enhanced (DCE-) MRI was performed in eighteen patients following neo-adjuvant chemotherapy. Data obtained from abnormal areas observed on conventional MR images were analysed with a two-compartment exchange model to obtain estimates of perfusion and permeability. The descriptive parameter, relative signal intensity at 80 s (rSI80s) was calculated. The bladder was examined for evidence of residual tumour and/or post-chemotherapy effect. DCE-MRI parameters obtained in areas of residual tumour were significantly higher than those obtained in areas of post-chemotherapy effect.

Hasan Alsaid¹, Stephen C Lenhard², Weike Bao², Mary V Rambo³, Alan R Olzinski², Gregory A Logan⁴, Mark E Burgert⁵, James R Tunstead⁶, Hilary S Eidam², Krista B Goodman², Mui Cheung², Robert N Willette², Kevin S Thorneloe², and Beat M Jucker^2,3
1Preclinical & Translational Imaging, GlaxoSmithKline, King of Prussia, PA, United States, ²Heart Failure DPU, Metabolic Pathways and Cardiovascular Therapy Area Unit,³Preclinical & Translational Imaging, ⁴Respiratory Therapy Area Unit, ⁵Discovery Analytics, ⁶Platform Technology & Science

Activation of TRPV4 increases lung permeability, leading to the formation of lung edema. GSK2193874A is a novel TRPV4 channel blocker that inhibits TRPV4 Ca2+ flux (in-vitro, IC50 =2nM). In this study, we tested whether GSK2193874A could prevent and/or reverse pulmonary edema and improve pulmonary function assessed by 1H-MRI in a murine heart failure model. MRI results revealed GSK2193874A significantly reduced lung water signal intensity, lung volume and edema. However, no effect was observed on cardiac function and remodeling. These results suggest MRI may be used to assess the therapeutic benefit of TRPV4 channel blockade on pulmonary edema in heart failure.

Eriko Yoshimaru¹, Julio Cárdenas-Rodríguez², Mark D Pagel², Robert Erickson^3,4, and Theodore Trouard^1
1Biomedical Engineering, University of Arizona, Tucson, Arizona, United States, ²Department of Chemistry, University of Arizona, Tucson, Arizona, United States, ³Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, United States, ⁴Pediatrics, University of Arizona

Diagnosis and treatment of many illnesses could be improved by MRI of lung inflammation and functional compromise. However, such imaging using traditional MRI methods is difficult. Recently, 19F MRI of perfluorocarbon emulsions have shown sensitivity to the presence of macrophages and monocytes in areas of inflammation. In this work, we present 1H and 19F spin-echo and Ultrashort TE (UTE) MRI to obtain 2D and 3D volumetric images of mouse models of cystic fibrosis (CF) and Niemann-Pick type C (NPC) disease. The UTE techniques used allow for motion insensitive 3D imaging of lung tissue and inflammation-associated perflorocarbon accumulation.

Anne Schmieder¹, Shelton Caruthers¹, John Stacy Allen¹, Todd Williams¹, Elizabeth Wagner², Samuel Wickline¹, and Gregory Lanza^1
1Washington University Medical School, St Louis, MO, United States, ²Johns Hopkins University, Baltimore, MD, United States

Asthma related proliferating bronchial neovasculature contributes to a sustained decrement in pulmonary function. In this study, a rat model of bronchial vascular proliferation was used to demonstrate noninvasive, high resolution molecular imaging of lung angiogenesis with dual 1H/19F MRI of αvβ3-targeted nanoparticles using a commercial 3T scanner. A novel steady state, ultrashort echo time technique was employed with a 3D radial readout scheme. The successful imaging of lung angiogenesis with this technique demonstrates a clinically translatable approach to monitor temporal-spatial changes in airway vascularity and potentially to deliver and monitor antiangiogenic therapy in order to ameliorate the progression of moderate to severe asthma.

Klaus Strobel¹, Verena Hoerr¹, Florian Schmid¹, Lydia Wachsmuth¹, and Cornelius Faber^1
1University Hospital Münster, Münster, Germany

Preclinical diagnosis of lung inflammation with T₂^* weighed protocols after systemic application of super paramagnetic iron oxide nanoparticles (SPIOs) is considered impossible because of the strong intrinsic susceptibility effects between lung parenchyma and alveolar spaces. Here we implemented an ultra-short echo time (UTE) sequence and successfully detected positive contrast in the lung after systemic administration of SPIOs in a mouse model of lung inflammation.

Alexandra R Morgan^1,2, Arousa Ali¹, Penny L Hubbard^1,2, Geoff JM Parker^1,2, Marietta LJ Scott³, Simon S Young³, Lars E Olsson⁴, Caleb Roberts^1,2, and Josephine H Naish^1,2
1Imaging Science, School of Cancer and Enabling Sciences, Manchester Academic Health Science Centre, The University of Manchester, Manchester, Greater Manchester, United Kingdom, ²Biomedical Imaging Institute, The University of Manchester, Manchester, Greater Manchester, United Kingdom, ³AstraZeneca R&D, Alderley Park, Macclesfield, United Kingdom, ⁴AstraZeneca R&D, Mölndal, Sweden

Pixel-wise analysis of pulmonary images acquired using oxygen-enhanced magnetic resonance imaging (OE-MRI) is challenging because of non-linear changes in shape and size of the lung during free breathing. A new non-linear image registration method is presented here, utilizing a lung motion model derived on a subject-by-subject basis from serial structural imaging. The method is shown to be advantageous when compared with no registration and with a 1-D linear registration, reducing error in fitting baseline T1 maps post-registration and alleviating motion induced signal intensity fluctuations in dynamic OE-MRI of oxygen wash-in/-out.

Alexandra R Morgan^1,2, Geoff JM Parker^1,2, Tim F Cootes^1,2, Marietta LJ Scott³, and Josephine H Naish^1,2
1Imaging Science, School of Cancer and Enabling Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester, Greater Manchester, United Kingdom, ²Biomedical Imaging Institute, The University of Manchester, Manchester, Greater Manchester, United Kingdom, ³AstraZeneca R&D, Alderley Park, Macclesfield, United Kingdom

Current diagnosis methods in lung disease are not capable of examining local pathological changes in respiratory dynamics and mechanical properties. We have developed a method for investigating regional lung motion in 3D using proton magnetic resonance imaging (MRI). A mesh-based group-wise affine image registration was utilised, in conjunction with rapid structural lung imaging, to produce maps of local lung motion in expiration. The method presented here is illustrated in healthy volunteers.

Helen Marshall¹, David G Kiely², David Capener¹, Martin H Deppe¹, Juan Parra-Robles¹, Andrew J Swift¹, Smitha Rajaram¹, Judith Hurdman², Robin Condliffe¹, Charles A Elliot¹, and Jim M Wild^1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom, ²Pulmonary Vascular Disease Unit, Sheffield Teaching Hospitals Trust

In Chronic Thromboembolic Pulmonary Hypertension perfusion can be imaged using scintigraphy, CTPA or ¹H MRI, but assessment of ventilation is usually limited to scintigraphy which has low spatial resolution and uses ionising radiation. ³He ventilation and ¹H perfusion MRI were used to image V/Q matching in six CTEPH patients, one patient was scanned both pre and post endarterectomy. The perfused lung volume and area of V-Q intersection were greatly increased by endarterectomy. V/Q MRI is useful for the assessment of ventilation and perfusion in CTEPH, and could provide a sensitive non-ionising means of monitoring patient response to interventions.

André Fischer¹, Stefan Weick², Christian Oliver Ritter¹, Dietbert Hahn¹, and Herbert Köstler^1
1Institute of Radiology, University of Wuerzburg, Wuerzburg, Germany, ²Department of Experimental Physics 5, University of Wuerzburg, Wuerzburg, Germany

This work presents a combination of retrospectively gated lung imaging using the DC signal and Fourier decomposition to obtain high resolution morphological and functional information. The data from six healthy volunteers were acquired using standard ¹H equipment without breathhold or ECG triggering on a clinical 3.0 T MR scanner. Perfusion- and ventilation-weighted images were successfully obtained and could be verified by comparison to standard Fourier decomposition (ventilation) and DCE-MRI (perfusion). In a following step, the proposed method will be tested on patients to investigate the diagnostic potential of this technique.

Grzegorz Bauman¹, Monika Eichinger², and Martin Uecker^3,4
1Dept. of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, ²Dept. of Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, ³Biomedizinische NMR Forschungs GmbH, Max-Planck-Institut für biophysikalische Chemie, Göttingen, Germany, ⁴Electrical Engineering and Computer Science, University of California, Berkeley, United States

In this work we show feasibility of a radial balanced steady-state free precession sequence with the nonlinear inverse reconstruction for acceleration of the proton lung image acquisition. The combination of efficient acquisition and novel reconstruction method provides very high temporal resolution up to 20 images per second. This technique can be used for ventilation- and perfusion-weighted Fourier decomposition MRI both to improve image quality and to obtain complimentary information regarding the blood inflow time in the thoracic vessels and lung parenchyma. The method was tested in a small group of volunteers and in a cystic fibrosis patient.

Penny L Hubbard^1,2, Geoff J M Parker^1,2, Dave Singh³, Eva Bondesson^4,5, Lars E Olsson⁴, Lars Wigström⁴, Simon S Young⁶, and Josephine H Naish^1,2
1Imaging Sciences, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom, ²The Biomedical Imaging Institute, The University of Manchester, Manchester, United Kingdom, ³Medicines Evaluation Unit, University Hospital Of South Manchester, The University of Manchester, Manchester, United Kingdom, ⁴AstraZeneca R& D, Sweden, ⁵Semcon Drug Development Consulting, Sweden, ⁶AstraZeneca R& D, United Kingdom

We present the results of a dynamic contrast-enhanced (DCE-) MRI study in subjects with Chronic Obstructive Pulmonary Disease (COPD) and age-matched healthy subjects. To our knowledge this is the first study to fit a pharmacokinetic model to an extended dynamic contrast-enhanced time series in this patient group. Fitting the extended Kety model revealed reductions in both the transfer coefficient (K^trans) and pulmonary blood volume (v_p) in severe COPD, but not moderate COPD. This is suggestive of reduced perfusion with increased disease severity.

André Fischer¹, Christian Oliver Ritter¹, Dietbert Hahn¹, and Herbert Köstler^1
1Institute of Radiology, University of Wuerzburg, Wuerzburg, Germany

SEEPAGE is a non-invasive non-contrast-enhanced technique to accurately quantify pulmonary perfusion in a single shot while requiring only short breathhold times. DCE-MRI is the gold-standard in quantitative lung MRI. However, it is invasive and requires longer breathhold times to sufficiently sample the passage of the contrast agent. No comparison of SEEPAGE to DCE-MRI has been performed yet. Therefore, this study directly compared quantified lung perfusion rates of four healthy volunteers obtained with SEEPAGE and DCE-MRI. Results demonstrate a good agreement of SEEPAGE perfusion values with DCE-MRI. Furthermore, this work reports the first successful application of SEEPAGE at 3.0 T.

Scott K Nagle^1,2, Jeffrey S Nackos¹, Mark L Schiebler¹, Christopher J Francois¹, Laura C Bell², Sean B Fain^1,2, and Kevin M Johnson^2
1Radiology, University of Wisconsin, Madison, WI, United States, ²Medical Physics, University of Wisconsin, Madison, WI, United States

Ultrashort echo time (UTE) techniques have been used successfully to image very short T2* tissues in the musculoskeletal system and more recently in animal lungs. In this work we demonstrate the feasibility of using 3D radial UTE MRI with an echo time of 80μs to image the lungs of sick patients with isotropic 1.25mm spatial resolution and full-chest coverage. The method is implemented on commercially available hardware, requires no breath-holds and is very robust to motion. The visualization of several different types of lung pathology were evaluated and compared to conventional echo time images acquired simultaneously using a dual-echo approach.

Stanley J Kruger¹, Kevin M Johnson¹, Sean B Fain^1,2, Robert V Cadman¹, Laura C Bell¹, and Scott K Nagle^1,3
1Medical Physics, University of Wisconsin, Madison, WI, United States, ²Biomedical Engineering, University of Wisconsin, Madison, WI, United States, ³Radiology, University of Wisconsin, Madison, WI, United States

Oxygen Enhanced MRI of lung parenchyma has so far relied on a SSFSE sequence paired with an inversion recovery to mitigate T2* decay and provide ample contrast in the low signal environment. Coverage is often limited, and multiple acquisitions are required to obtain adequate SNR. Radial 3D UTE-SPGR is a new technique in oxygen enhanced MRI that combines oversampling the center of k-space as well as short TE to yield a 3D isotropic volume of oxygen enhanced signal that is robust against cardiac motion artifact and T2* decay, while providing full lung coverage in any orientation.

Weijuan Zhang^1,2, Penny L Hubbard^1,2, Eva Bondesson³, Lars Wigström⁴, Simon S Young⁵, David Singh⁶, Geoffrey JM Parker^1,2, and Josephine H Naish^1,2
1Imaging Sciences, School of Cancer & Enabling Sciences, The University of Manchester, Manchester, United Kingdom, ²The Biomedical Imaging Institute, The University of Manchester, Manchester, United Kingdom, ³Semcon Drug Development Consulting, Lund, Sweden, ⁴AstraZeneca R&D, Lund, Sweden, ⁵AstraZeneca R&D, Chamwood, United Kingdom, ⁶University Hospital of South Manchester Foundation Trust, Manchester, United Kingdom

Single-slice coronal oxygen-enhanced MRI were performed in 24 patients with chronic obstructive pulmonary disease (COPD) and 12 healthy volunteers, from which color-coded V/Q maps were extracted by pixelwise model fitting. COPD lungs were then structurally classified into emphysematous and non-emphysematous subgroups according to percentage of low attenuation areas under -950 Hounsfield units in matched 2D CT images. COPD patients have considerably heterogeneous V/Q maps whether or not emphysema is present. a significant positive correlation between LAA% and IQR-V/Q in emphysematous COPD (r=0.449, p=0.017), while there is no significant correlation in non-emphysematous COPD. In addition, there is no significant correlation between median log10 V/Q and LAA% in either COPD group.Within the slice, the V/Q distribution becomes more heterogeneous with increasing emphysema, while in non-emphysematous COPD, other factors, possibly including airway blockage and inflammation, may be responsible for the V/Q change. regional V/Q mismatch whether or not emphysema is present.V/Q maps in both types of COPD were much more heterogeneous than those in healthy subjects, while they showed similar or mildly lower heterogeneity in non-emphysematous COPD than in emphysematous COPD, which demonstrates that comparative ventilation-perfusion mismatch exists in COPD even if there is no emphysema. To explore the potentially different structure-function relationship in two types of COPD, correlations between CT parameters and OE-MRI parameters were measured. Median V/Q did not correlate with LLA% in both COPD groups. However, inter-quartile range of V/Q (V/QIQR), representing the extent of heterogeneity, was fairly correlated with LLA% in emphysematous COPD (r=0.449, p=0.017), indicating V/Q mismatch in COPD gets worse as emphysema increases. However, the correlation was not found in non-emphysematous COPD. This study elucidates that distinction between emphysematous COPD and non-emphysematous COPD does not affect the presence of V/Q imbalance substantially but that the relationship between V/Q and the CT measures does vary between these two types.

Michael Völker¹, Shermiyah Baguisa², Martin Blaimer¹, Felix Breuer¹, and Peter Jakob^1,3
1Magnetic Resonance Bavaria, Würzburg, Germany, ²Department of Physics, Ryerson University, Toronto, Canada, ³Department of Experimental Physics 5, University of Würzburg, Germany

We show that fast T₂ relaxometry of the human lung is feasible using an efficient radial TSE sequence for data acquisition followed by a model-based nonlinear reconstruction approach. T₂ maps for multiple slices were obtained in one single breathhold of 13s.

John P. Mugler, III¹, Talissa A. Altes¹, Iulian C. Ruset^2,3, G. Wilson Miller¹, Jaime F. Mata¹, Kun Qing⁴, Igor Tsentalovich², F. William Hersman^2,3, and Kai Ruppert^1
1Radiology & Medical Imaging, University of Virginia, Charlottesville, VA, United States, ²Physics, University of New Hampshire, Durham, NH, United States, ³Xemed, LLC, Durham, NH, United States, ⁴Biomedical Engineering, University of Virginia, Charlottesville, VA, United States

The T2* of dissolved-phase Xe129 in the lung was measured in three healthy subjects. Median T2* values ranged between 2.0 and 2.3 ms.

Felix Clemens Horn¹, Martin Heiner Deppe¹, Helen Marshall¹, Graham Norquay¹, Juan Parra-Robles¹, and Jim Wild^1
1University of Sheffield, Sheffield, South Yorkshire, United Kingdom

The effects of gravity in multiple-breath inert gas washout MRI of hyperpolarised ³He and ¹²⁹Xe with 2D and 3D imaging are demonstrated in a volunteer at 1.5 T. To compare different washout experiments the regional fractional ventilation factor r (=% of gas exchanged per breath) was used. It is seen that the gravitational effects are irrespective of imaging sequence and gas type being used and the offset between r-values of different experiments is likely to be dependent upon the gas used, on sequence and respirational volume.

Kai Ruppert¹, Talissa A. Altes¹, Iulian C. Ruset², G. Wilson Miller¹, Jaime F. Mata¹, Kun Qing¹, Igor Tsentalovich³, F. William Hersman^2,3, and John P. Mugler III^1
1University of Virginia, Charlottesville, VA, United States, ²Xemed LLC, Durham, NH, United States, ³University of New Hampshire, Durham, NH, United States

The T2* of hyperpolarized xenon-129 dissolved in lung tissue is about 2 ms, which greatly reduces the resulting signal amplitude for most gradient-echo pulse sequences. In this work, we measured the T2 of dissolved-phase xenon using a global CPMG echo-train spectroscopic pulse sequence and identified a large (85%) signal component with a T2 of ~18 ms and a smaller (15%) component with a T2 of ~400 ms. The long T2 component would be suitable for direct imaging using a spin-echo sequence. However, due to its small amplitude, an improvement in image quality over existing gradient-echo pulse sequences remains doubtful.

Nikhil Kanhere^1,2, Miranda Kirby^1,3, Andrew Wheatley¹, Alexei Ouriadov¹, Giles E Santyr^1,3, David G McCormack⁴, and Grace Parraga^1,2
1Robarts Research Institute, London, Ontario, Canada, ²Graduate Program in Biomedical Engineering, The University of Western Ontario, ³Medical Biophysics, The University of Western Ontario, ⁴Division of Respirology, Department of Medicine, The University of Western Ontario

The objective was to determine the reproducibility of hyperpolarized xenon-129 (¹²⁹Xe) magnetic resonance imaging (MRI) measurements within the same day (5-min rescan) and after 7-days in chronic obstructive pulmonary disease (COPD) ex-smokers. For all subjects (n=9) there was no significant difference for ¹²⁹Xe ventilation defect percent (VDP) between the scan and 5-min rescan (p=.80) nor was there a significant difference between all three time-points for the three COPD subjects that returned for 7-day imaging (p=.06). These findings suggest that ¹²⁹Xe is a highly reproducible gas and a feasible alternative to ³He MRI with strong translational potential in COPD studies.

G. Wilson Miller¹, John P. Mugler III¹, Talissa A. Altes¹, Jaime F. Mata¹, Kai Ruppert¹, F. William Hersman², Jan Distelbrink², and Iulian C. Ruset^2
1Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, United States, ²Xemed LLC, Durham, New Hampshire

Lung pO₂ maps generated from T₁-weighted hyperpolarized-gas MR images often show unphysiological pO₂ values in the vicinity of the heart. These anomalous values are thought to result from cardiac motion during the breath-hold acquisition. We demonstrate that such artifacts can largely be eliminated by synchronizing image acquisition with the cardiac cycle.

Kai Ruppert¹, James D. Quirk², John P. Mugler III¹, Talissa A. Altes¹, Chengbo Wang¹, G. Wilson Miller¹, Iulian C. Ruset^3,4, Jaime F. Mata¹, F. William Hersman^3,4, and Dmitriy A. Yablonskiy^2
1University of Virginia, Charlottesville, VA, United States, ²Washington University, St. Louis, MO, United States, ³Xemed LLC, Durham, NH, United States, ⁴University of New Hampshire, Durham, NH, United States

The recently described helium-3 (He3) lung-morphometry technique, which is based on in-vivo MR measurements of the diffusivity of hyperpolarized He3 gas in the lung, provides information on parameters commonly used by lung physiologists to characterize lung morphometry. However, due to the high cost and limited supply of He3, lung morphometry with hyperpolarized xenon-129 (Xe129) might become an attractive alternative for widespread application. In this work we demonstrate the feasibility of Xe129 lung morphometry and present results that indicate a good agreement between the findings with He3, Xe129 and histology.

Kiarash Emami¹, Hooman Hamedani¹, Biao Han¹, Yinan Xu¹, Stephen J. Kadlecek¹, Masaru Ishii², and Rahim R. Rizi^1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, ²Otolaryngology - Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States

The design of an automatic MRI-compatible respiratory gas mixing, delivery and monitoring device capable of administering a predefined tidal volume and concentration of gaseous contrast agents to consciously breathing subjects is described. This system divides the mixture of hyperpolarized gas and oxygen over several breaths for multi-breath imaging protocols or oxygen-weighted MRI, queues the subject (without the risk of over-inflating the lungs) and synchronizes image acquisition with MRI scanner. This device eliminates the need for operator supervision by responding to subject’s voluntary respiratory effort, and makes it possible to maintain a respiratory pattern very similar to normal breathing.

Talissa A Altes¹, John P Mugler¹, Craig Meyer², Jaime H Mata¹, Peter Komlosi¹, Deborah Froh³, Grady Wilson Miller¹, F William Hersman⁴, Iulian C Russet⁴, Igor Tsentalovich⁴, Eduard E de Lange¹, Martyn C Botfield⁵, and Mac Johnson^5
1Radiology, University of Virginia, Charlottesville, VA, United States, ²Boimedical Engineering, University of Virginia, Charlottesville, VA, United States, ³Pediatric Pulmonology, University of Virginia, Charlottesville, VA, United States, ⁴Xemed, Durham, NH, United States, ⁵Vertex Pharmaceuticals Incorporated, Cambridge, MA, United States

Summary: Ventilation MRI of the lung has been performed with hyperpolarized helium-3 and xenon-129. It is not known whether the distribution within the lung of inhaled xenon-129, which has an atomic weight 43 times that of helium-3, is different from that for helium-3. In this study of 6 subjects with cystic fibrosis (CF), the size, location, and relative severity of the defects were nearly identical with helium-3 and xenon-129 for most subjects. In a few subjects the defects were more conspicuous, larger, and/or more numerous with xenon-129, which suggests xenon-129 may be more sensitive to areas of partial airflow obstruction.

Talissa A Altes¹, Craig H Meyer², Jaime H Mata¹, Deborah Froh³, Alix Paget-Brown³, Sean Fain⁴, Eduard E de Lange¹, Grady Wilson Miller¹, Karen Mooney¹, Gordon D Cates⁵, Martyn C Botfield⁶, Mac Johnson⁶, and John P Mugler^1
1Radiology, University of Virginia, Charlottesville, VA, United States, ²Boimedical Engineering, University of Virginia, Charlottesville, VA, United States, ³Pediatrics, University of Virginia, Charlottesville, VA, United States, ⁴Radiology, University of Wisconsin, Madison, WI, United States, ⁵Physics, University of Virginia, Charlottesville, VA, United States,⁶Vertex Pharmaceuticals Incorporated, Cambridge, MA, United States

As a prelude to clinical studies of infants with lung disease, the purpose of this study was to develop an acquisition strategy and hyperpolarized helium-3 (HHe) gas-delivery methods to enable imaging of non-sedated infants. HHe MRI was performed in a single non-sedated, non-restrained, healthy infant, age 13 months, using a spiral-based acquisition and a simple HHe gas-delivery system. The short acquisition time of 0.12 s per slice enabled imaging of a moving infant with little motion artifact. Similar to prior results in healthy older children and young adults, the healthy infant had homogeneous ventilation on HHe MRI.

Salma Ajraoui¹, and Jim M Wild^1
1University of Sheffield, Sheffield, Yorkshire, United Kingdom

In this work, dynamic 3He and 1H images were acquired in a synchronised scan during inhalation providing regional gas flow with spatially and temporally registered lung anatomy motion. Lung ventilation is very fast (air reaches lung periphery within 1s) and demands fast sequences that can capture the rapid flow of 3He gas in lung airways. Compressed Sensing (CS) was used to assess the feasibility of accelerated synchronous 3He/1H acquisition.

John P. Mugler, III¹, Karen E. Mooney², Talissa A. Altes¹, Jaime F. Mata¹, Kun Qing³, Eduard E. de Lange¹, William A. Tobias², James R. Brookeman¹, Gordon D. Cates, Jr.², and G. Wilson Miller^1
1Radiology & Medical Imaging, University of Virginia, Charlottesville, VA, United States, ²Physics, University of Virginia, Charlottesville, VA, United States, ³Biomedical Engineering, University of Virginia, Charlottesville, VA, United States

The purpose of this study was to perform a preliminary assessment of the quality of helium-3 (He3) ventilation MR images that can be obtained with a He3 dose of only 100 ml by combining increased polarization with a balanced steady-state free-precession (TrueFISP) acquisition. High-quality images, with SNR values ranging between 28 and 43, were obtained in five healthy subjects.

Helen Marshall¹, Martin H Deppe¹, Juan Parra-Robles¹, Sue Hillis², Catherine Billings², Smitha Rajaram¹, Andrew J Swift¹, Sam R Miller³, Joanna H Watson³, Jan Wolber⁴, David A Lipson⁵, Rod Lawson², and Jim M Wild^1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom, ²Respiratory Medicine, Sheffield Teaching Hospitals NHS Trust, ³GlaxoSmithKline, Stockley Park, ⁴GE Healthcare, Amersham, ⁵GlaxoSmithKline, King of Prussia

Collateral ventilation is an important mechanism in Chronic Obstructive Pulmonary Disease but limited observations of it have been demonstrated in vivo. 10 COPD patients were scanned with hyperpolarised. ³He MRI using a time-resolved 3D sequence. ³He was observed moving into lung regions which were initially non-ventilated during a static breath-hold. The images show direct visual evidence of delayed gas ventilation in what we believe to be collateral ventilation in COPD. Delayed-filling of peripheral regions was also observed in some patients which may be due to increased flow resistance in the small airways.

Talissa A Altes¹, Mac Johnson², John P Mugler¹, Deborah Froh³, Lucia Flors¹, Grady Wilson Miller¹, Jaime H Mata¹, Carlos L Salinas¹, Nick Tustison¹, Po-Shun Lee², Tao Song², Karl Yen², Eduard E de Lange¹, and Martyn C Botfield^2
1Radiology, University of Virginia, Charlottesville, VA, United States, ²Vertex Pharmaceuticals Incorporated, Cambridge, MA, United States, ³Pediatric Pulmonology, University of Virginia, Charlottesville, VA, United States

This study to evaluate the ability of hyperpolarized helium-3 MR ventilation imaging to detect the effects of treatment with ivacaftor, a CFTR potentiator, demonstrated a rapid onset of improvement in lung ventilation with treatment and equally rapid return to near baseline ventilation following cessation of treatment. Eight subjects with CF were imaged on 5 different days, 2 weeks apart (Days 0, 14, 28, 42, and 56), and were treated with Ivacaftor from Days 14 to 42. Interim data analysis has been conducted on the first 4 subjects in the study, although all 8 subjects have completed the trial.

Karen E. Mooney¹, Walter H. Whitlock², Thomas C. Hyde², John P. Mugler III³, Talissa A. Altes³, Jamie F. Mata³, Gordon D. Cates Jr.^1,3, Eduard E. de Lange³, and G. Wilson Miller^3
1Physics, University of Virginia, Charlottesville, Virginia, United States, ²Conservation Design Services, Inc., Chapel Hill, NC, ³Radiology, University of Virginia

Our group has begun a program to collect 3-helium from human imaging studies for future recycling. The materials and method of collection are described and gas analysis results are presented.

Adam Farag¹, Jian Wang², Alexei Ouriadov¹, Grace Parraga^1,3, and Giles Santyr^1,3
1Imaging Research Laboratory, Robarts Research Institute, London, Ontario, Canada, ²Applied Science Laboratory, GE Healthcare, ³Dept. of Medical Biophysics

The revolution of the MRI today made it more possible to achieve the impossible. New hardware designs are certainly part of this, and in particular unconventional RF coils.

Jian-Jia Chiu¹, Yi-Ru Lin¹, and Shang-Yueh Tsai^2,3
1Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan, ²Graduate Institute of Applied Physics, National Chengchi University, Taipei, Taiwan, ³Reasearch Center for Mind, Brain and Learning, National Chengchi University, Taipei, Taiwan

Early detection of non-alcoholic fatty liver disease can prevent further complications such as steatohepatitis, fibrosis and cirrhosis. Previous we have shown that proton echo planar spectroscopic imaging (PEPSI) is able to detect spatial distribution of liver fat content. Here we further investigated the influence of T2 relaxation effects. Non-water suppressed liver spectra were obtained using PEPSI sequence. PEPSI scans were repeated 8 times to observe the reproducibility of T2 correction. Our results showed that hepatic fat content distribution with T2 correction can be achieved in less than 3 minutes with our protocol. And the measured fat content is highly reproducible.

Alessandra Laufs¹, Roshan Livingstone¹, Sabine Link¹, Bettina Nowotny¹, Birgit Klueppelholz², Guido Giani², Jürgen Bunke³, Michael Roden^1,4, and Jong-Hee Hwang^1
1Institute for Clinical Diabetology, German Diabetes Center, Düsseldorf, Germany, ²Institute for Biometry and Epidemiology, German Diabetes Center, Düsseldorf, Germany,³Philips Healthcare, Hamburg, Germany, ⁴Department of Metabolic Diseases, University Clinics Düsseldorf, Heinrich Heine University, Düsseldorf, Germany

In order to evaluate relations between age, liver fat, and ATP in the liver in 51 healthy subjects over 40 years old, liver fat by ¹H MRS and ³¹P MRS of liver using 3D ISIS were obtained on a 3T scanner. As a result, the mean values of -ATP/Pi ratios and the liver fat content were 1.25±0.29 and 4.5±6%. ATP/Pi correlated with liver fat (r=0.29, p<0.05), and liver fat correlated with age(r=0.36, p<0.05). BMI did not correlate with ATP/Pi.

Thobias Romu^1,2, Louise Elander³, Magnus Borga^1,2, and Olof Dahlqvist Leinhard^2,4
1Department of Biomedical Engineering, Linköpings Universitet, Linköping, Ostergotland, Sweden, ²CMIV, Linköpings Universitet, Linköping, Sweden, ³County Council of Ostergotland, Linköping, Sweden, ⁴Depts of Radiation Physics, Linköping University and Radiation Physics, UHL County Council of Ostergotland, Linköping, Sweden

When leaving the comfortable zone of the first OP/IP echo’s small adjustments in TE can make a huge difference for symmetrically sampled Dixon imaging. Fortunately on the fly compensation is relatively easy using a short single voxel spectroscopy scan and a model of the fat/water interference. The method is tested using the second OP and third IP echo, both in vitro and in vivo.

Xinwei Shi¹, Haining Liu¹, Chun Yuan^1,2, and Hua Guo^1
1Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, ²Department of Radiology, University of Washington, Seattle, WA, United States

IDEAL (Iterative decomposition of water and fat with echo asymmetry and least-squares estimation) algorithm incorporating with multi-peak fat spectral modeling can provide complete water-fat separation, and thus is an effective way for fat quantification or fat suppression. Since the fat spectra vary in different tissue, a self-calibration method is needed to accurately measure the fat frequency model in the interested region. In this work, we analyze the performance of multi-peak IDEAL algorithm with self-calibrated fat spectrum by simulation, phantom and in vivo experiments and find optimized echo time increments which provide reliable water-fat separation.

Haining Liu¹, Xinwei Shi², Chun Yuan³, and Hua Guo^2
1Center for Bio-Medical Imaging Research, Tsinghua University, Beijing, Beijing, China, ²Tsinghua University, ³Department of Radiology, University of Washington, Seattle, WA

Noise performance for chemical-shift based multi-point water-fat separation method is affected by the selection of echo time combination. The purpose of this work is to find optimal TE1 and deltaTE combinations through Monte Carlo simulations and phantom experiments. The variance of R2* estimation using T2* IDEAL algorithm based on the multi-peak fat spectrum is evaluated. The results from the simulations and experiments are consistent with each other, and an optimal TE1 and deltaTE combination range is found. The limitation of Cramer-Rao bound theory on the evaluation of R2* variance also discussed.

R D Sims¹, Q Yuan¹, G Khatri¹, P T Weatherall¹, R Batz¹, S Zhang², I Pedrosa¹, and N M Rofsky^1
1Radiology, UT Southwestern Medical Center, Dallas, Texas, United States, ²Clinical Sciences, UT Southwestern Medical Center

The feasibility of the multiecho 2-Point Dixon (mDIXON) technique to produce images comparable to conventional 3D fat suppressed T1weighted gradient echo (eTHRIVE) images, while eliminating the need for separate 2D chemical shift imaging, has been shown. We performed a multi-parametric comparison of the latest version of mDIXON to our previous standard 2D and 3D T1weighted techniques. Our results confirm a statistically significant improvement in homogeneity of fat exclusion and reduction of artifacts compared to eTHRIVE, as well as improved relative signal and contrast, while reducing breath hold duration and overall scan time.

Qiong Ye¹, Yuan Mei², and Markus Rudin^1,3
1Institute for Biomedical Engineering, Zürich, Zürich, Switzerland, ²Nuclear Science Division,Lawrence Berkeley National Laboratory, Berkeley, California, United States,³Institute of Pharmacology and Toxicology, Zürich, Switzerland

Magnetic resonance imaging at different echo times are acquired from phantom and neck in ob/+ control mice in a 9.4T system. In this work, Fourier Transform was applied at TEs to differentiate individual peaks. Results from phantom are very promising. Derived results from neck of ob/+ control mouse are in good agreement with theory also. From the spatial distribution of individual peaks, this method is able to differentiate water and lipid composition. More images are required for decent spectral resolution.

Stephen James Bawden¹, Mary C Stephenson², Luca Marciani³, Guruprasad P Aithal³, Ian A Macdonald³, Penny A Gowland², and Peter G Morris^2
1SPMMRC, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, ²SPMMRC, University of Nottingham, ³Nottingham Digestive Diseases Biomedical Research Unit, University of Nottingham

Fructose metabolism is known to deplete hepatic ATP stores due to unregulated phosphorolation. In previous studies rate of ATP replenishment following fructose infusion as measured using 31P Magnetic Resonance Spectroscopy has been inversely correlated with steatosis in non alcoholic fatty liver disease (NAFLD) and with BMI. In this pilot study we show ATP depletion and recovery following oral fructose intake (equivalent sugar content ~2 cans of coke). Results are more consistent across subjects when fructose is ingested with glucose (1:1 ratio) due to decreased variation in intestinal absorption rates

Steve Bandula¹, Dan Sado², Jason Yeung³, Catherine Morgan³, Shonit Punwani³, Stuart Taylor³, Stefan Piechnik⁴, and James Moon^5
1Centre for Medical Imaging, University College London, London, London, United Kingdom, ²The Heart Hospital, London, ³University College London, ⁴University of Oxford,⁵The Heart Hospital Imaging Centre, The Heart Hospital, London

Equilibrium MRI (EQ-MRI) is a new non-invasive technique which has been shown to accurately quantify the extracellular volume. It may provide a useful technique for assessment of diseases which cause a diffuse expansion of the extracellular space. We used EQ-MRI with ShMOLLI T1 mapping to measure the extracellular volume within various tissues in 38 normal volunteers. Measured values in several tissues had narrow interquartile ranges. Values were also similar to those quoted in the literature, measured using Dynamic Contrast Enhanced MRI (DCE-MRI). EQ-MRI may provide a useful tool for discrimination between normal and diseased tissue.

Sanaz Mohajeri^1,2, Tedros Bezabeh¹, Scott B. King¹, Omkar B. Ijare¹, M.A. Thomas³, Gerald Minuk², Jeremy Lipschitz², Allan B. Micflikier², Iain Kirkpatrick², Lawrence Ryner¹, and Ian C.P. Smith^1
1National Research Council, Institute for Biodiagnostics, Winnipeg, Manitoba, Canada, ²University of Manitoba, Winnipeg, Manitoba, Canada, ³University of California, Los Angeles

Cholestasis results from failure to clear bile from the liver into the duodenum. Prolonged cholestasis results in accumulation of bile salts and hepatocellular damage. Phosphatidylcholine and glycine/taurine conjugated bile acids may play a role in the pathophysiology of cholestasis. Primary Scelerosing Cholangitis (PSC) is a chronic cholestatic liver disorder with inflammation, narrowing and finally obstruction of bile ducts. Considering the success of in vivo 1-H MRS in detecting human bile components, we are comparing in this study 1-D and 2-D spectra of human bile in healthy volunteers and PSC patients obtained using a 3T clinical scanner and our home-built receive array coil.

Omkar B. Ijare¹, Tedros Bezabeh¹, Nils Albiin², Annika Bergquist², Urban Arnelo², Matthias Löhr², Alexey Shiryaev³, B. S. Somashekar⁴, G.A. Nagana Gowda⁴, V.K. Kapoor⁵, C.L. Khetrapal⁴, and Ian C.P. Smith^1
1National Research Council Institute for Biodiagnostics, Winnipeg, Manitoba, Canada, ²Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden, ³Norwegian PSC Research Center, Oslo University Hospital Rikshospitalet, Oslo, Norway, ⁴Centre of Biomedical Magnetic Resonance, SGPGIMS Campus, Lucknow, India, ⁵Sanjay Gandhi Post-Graduate Institute of Medical Sciences, Lucknow, India

Pancreaticobiliary (PB) reflux has been considered to be a potential risk factor for the carcinogenesis of bile ducts and gallbladder (GB). Previous ex vivo studies tested the suitability of MRS for the detection of PB reflux through the analysis of bile. In this study, we analyzed bile samples from patients with cholangiocarcinoma (n = 3) and GB cancer (n = 7) to determine if any of these patients possess regurgitation. We observed this phenomenon in 1/3 cholangiocarcinoma and 5/7 GB cancer patients, supporting the fact that PB reflux is a risk factor for the carcinogenesis of bile ducts and GB.

Ronald Ouwerkerk¹, and Ahmed Medhat Gharib^2
1Metabolic Imaging Branch, NIDDK/NIH, Bethesda, MD, United States, ²Metabolic Imaging Branch, NIH/NIDDK, Bethesda, MD, United States

Metabolites in the pancreas of healthy human subjects were measured with single volume PRESS ¹H-MRS. In one subject the T₂ relaxation times for lipid, choline and water were determined. Breath hold B0 field mapping improved spectral quality and navigator gated suppression of breathing motion helped avoid spurious lipid signals from surrounding tissues. Spectra contained signals of choline at 3.2 ppm, creatine at 3.0 ppm, and possibly glycerol, glucose or glycogen. The concentration of choline was 17.5±7.0 mmol/l (N=7, range 7.4-25.1). The T₂ relaxation times for lipid choline and water were 101, 98 and 48 ms respectively in one subject.

Alexander Peter Lin¹, Sai Merugumala¹, Saadallah Ramadan², Huijun Liao¹, Paolo Fiorina³, Anil Chandraker⁴, and Carolyn Mountford^1,2
1Radiology, Center for Clinical Spectroscopy, Brigham and Women's Hospital, Boston, MA, United States, ²Centre for MR in Health, University of Newcastle, Callaghan, New South Wales, Australia, ³Transplant Research Center, Children’s Hospital Boston, Boston, MA, United States, ⁴Renal Division, Brigham and Women's Hospital, Boston, MA, United States

There is a need to identify early biomarkers of transplanted kidney dysfunction that are non-invasive. This study describes the optimization of one-dimensional and novel two-dimensional magnetic resonance spectroscopy methods to identify such biomarkers. The results showed that acquisition using a phased array torso coil, weak water suppression with water reference, voxel size of 13.5cc, and 2D COSY scan time of 11 minutes provided metabolite measurements of choline, triglycerides, unsaturated fatty acids, olefinic fat, methylene and methyl fat resonances. These results provide the basis for future studies to determine the potential of these metabolic biomarkers in early detection and treatment monitoring.

Candice A. Bookwalter¹, Michael W. Harrell², Nicole Seiberlich³, Smitha Thomas¹, Raj Mohan Paspulati¹, Jeremiah A. Heilman⁴, Mark A. Griswold^1,3, and Vikas Gulani^1,3
1Department of Radiology, University Hospitals Case Medical Center/Case Western Reserve University, Cleveland, OH, United States, ²School of Medicine, Case Western Reserve University, Cleveland, OH, United States, ³Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, ⁴Quality Electrodynamics, Mayfield Village, OH, United States

The automatic and retrospective method of Motion Artifact Removal by Retrospective Resolution Reduction (MARs) is evaluated in conjunction with parallel imaging time acceleration in both simulation and patient data. MARs uses GRAPPA navigators to detect motion corrupted data and subsequently removes corrupted data to obtain a motion artifact free yet lower resolution image. The MARs method is shown to work robustly with parallel imaging time acceleration. Image evaluation was performed using alternate force choice ratings. MARs corrected images were shown to be preferred over uncorrected images.

Michael W. Harrell¹, Katherine L. Wright², John Jesberger^1,3, Luis Landeras^1,3, Dean Nakamoto^1,3, Smitha Thomas^1,3, Dominik Nickel⁴, Randall Kroeker⁴, Mark A. Griswold^2,3, and Vikas Gulani^1,3
1School of Medicine, Case Western Reserve University, Cleveland, OH, United States, ²Dept. of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, ³Dept. of Radiology, University Hospitals of Cleveland and Case Western Reserve University, Cleveland, OH, United States, ⁴Siemens Medical Solutions, Erlangen, Germany

CAIPIRINHA (Controlled Aliasing In Parallel Imaging Results IN Higher Acceleration) is an imaging technique that modifies aliasing artifacts during image acquisition, which potentially allows for a more robust parallel imaging reconstruction with fewer aliasing artifacts. Here this was tested by comparing CAIPIRINHA against a clinically standard GRAPPA acquisition for highly accelerated breath hold liver scans. Evaluation of the image quality of CAIPIRINHA by three blinded, untrained radiologists demonstrated a statistically significant improvement in clinical image quality in comparison to a standard GRAPPA.

Taeho Kim¹, and Paul Keall^1
1Radiation Physics Laboratory, Unviersity of Sydney, Camperdown, NSW, Australia

The quality of the radiation treatments can be compromised by involuntary respiratory motion, which can reduce image quality and tumor control (4-5% dose variation per 5 mm tumor excursion). Respiratory gating and breath-hold methods for respiratory motion-compensation are practically useful, but respiratory gating increases scan time and breath-hold requires the patient¡¯s full cooperation during the scan. The aim of this study is to develop a novel respiratory motion control system using audiovisual (AV) biofeedback combined with abdomen MRI and to demonstrate improved abdominal position reproducibility and reduced motion artifacts in breath-hold MRI.

S. D. Swanson¹, D. I. Malyarenko¹, P. Schmiedlin-Ren², J. Adler³, K. Helvie², L. Reingold², M. M. Al-Hawary¹, and E. Zimmerman^2
1Department of Radiology, University of Michigan, Ann Arbor, Michigan, United States, ²Department of Internal Medicine:Gastroenterology, University of Michigan,³Department of Pediatrics and Communicable Disease, University of Michigan

 

Daniel Jirak^1,2, Jan Kriz¹, Eva Vodraskova¹, Klara Zacharovova¹, Frantisek Saudek¹, and Milan Hajek^1
1Institute for Clinical and Experimental Medicine, Prague, Czech Republic, ²1st Medical Faculty, Institute of biophysics and informatics, Charles University, Prague, Czech Republic

To improve transplantation outcome, artificially created sites for cell transplantation have gained attention. The aim of our study was to evaluate the blood supply of the artificial cavities for islet transplantation in a preclinical rat model. Two biocompatible scaffolds were implanted subcutaneously and into greater omentum of the same animal. The blood supply of these devices was assessed by dynamic contrast–enhanced magnetic resonance imaging within four weeks following implantation. Our results indicate that artificial device implanted into greater omentum possesses superior blood supply for the transplanted cells and optimal time for cell transplantation is one week after implantation.