Electronic Posters : Body (Non-Cancer) Imaging
Click on to view the abstract pdf and click on to view the video presentation.
Body Diffusion: Technique & Clinical Applications

Monday May 9th
Exhibition Hall  14:00 - 16:00 Computer 4

14:00 2978.   Investigating the contribution of osteoblastic activity to ADC of bone metastases by correlating changes in ADC with changes in T2* and HU  
Christina Messiou1, David J Collins1, Matthew Robson2, Veronica A Morgan1, Catherine Simpkin1, Diletta Bianchini3, Johann S de Bono3, and Nandita deSouza1
1CRUK & EPSRC Cancer Imaging Centre, Institute of Cancer Research & Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom, 2Dept. of Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom, 3Dept. of Medicine, Institute of Cancer Research & Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom

The aim of this study was to investigate the contribution of osteoblastic activity to ADC of bone metastases from prostate carcinoma undergoing treatment by correlating changes in ADC with changes in T2* and HU. Percentage changes in ADC did not correlate with percentage change in HU or T2*. This may be because intertrabecular distance is beyond the range interrogated by the DWI technique employed in this study. Because intertrabecular distance is so large relative to cell size, a marked sclerotic response may be required to bring intratrabecular distances down to a level where it affects intercellular distances and diminishes ADC.

14:30 2979.   Improved diagnostic accuracy of whole body diffusion weighted MRI using computed imaging. 
Matthew David Blackledge1, Nina Tunariu1, David J Collins1, Martin O Leach1, and Dow Mu Koh1
1CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden Hospital, Sutton, Surrey, United Kingdom

A recent methodology known as computed diffusion weighted imaging (cDWI) has demonstrated that improved SNR may achieved at high b-values by acquiring images at multiple b-values, calculating the apparent diffusion coefficient maps and using the results to simulate the signal at a desired b-value. In the present study we compare the diagnostic utility of cDWI, computed at b-values of 1500 and 2000 s/mm2, with conventional DWI, acquired at 900 s/mm2, in a small cohort of patients diagnosed with advanced metastatic disease.

15:00 2980.   Whole-body MR-imaging allows to differentiate indolent from aggressive systemic mastocytosis 
Henrik J Michaely1, Georgia Metzgeroth2, Philipp Riffel1, Stefan Haneder1, W K Hofmann2, Stefan O Schoenberg1, and Andreas Reiter2
1University Medical Center Mannheim, Mannheim, BaWue, Germany, 2Oncolocy, University Medical Center Mannheim, Mannheim, BaWue, Germany

Systemic mastocytosis is a rare clonal stemm cell disease occurring in different manifestations: aggressive systemic mastocytosis, smouldering mastocytosis and indolent mastocytosis. In this study wb-MRI was employed to detect the various manifestations of systemic mastocytosis which allowed to safely differentiate between the subtypes of the disease.

15:30 2981.   Diffusion-Weighted Imaging of Retroperitoneal Fibrosis and Retroperitoneal Lymphoma: Can Apparent Diffusion Coefficient Values Distinguish the Two? 
Bradley Spieler1, Caludia Reuben Seuss1, Daniel Sahlein1, and Sooah Kim1
1Radiology, New York University, New York, NY, United States

27 patients with histopathologically proven retroperitoneal lymphoma (n=16) and retroperitoneal fibrosis (RPF, n=11) who underwent MRI including DWI using b-values of 0, 400, and 800 sec/mm2 at 1.5T were included. Two readers measured ADCs independently. ADC values of lymphoma and RPF were compared by independent sample t-test. There was no statistical difference in measured ADC between lymphoma (1.26 *10-3mm2/sec, range 0.54-2.03 *10-3mm2/sec) and RPF (1.35 *10-3mm2/sec, range 0.61-2.45 *10-3mm2/sec) (p=0.57).

Tuesday May 10th
  13:30 - 15:30 Computer 4

13:30 2982.   Diffusion-weighted MRI of normal sized pelvic lymph nodes: how to delineate an ideal region of interest? 
Daniel Guo Quae Chong1, Giuseppe Petralia1,2, Michael Ith1, Johnannes Michael Froehlich1,3, and Harriet Thoeny1
1Dept. of Diagnostic, Interventional and Pediatric Radiology (DIPR), Inselspital, Bern, Switzerland, 2Division of Radiology, European Institute of Oncology, Milan, Italy,3Guerbet AG, Zurich, Switzerland

Small structure such as lymph nodes are difficult to visualized with diffusion weighted imaging. Due to the lower resolution of DWI and the size of typical lymph node, it is often the case only 1-4 pixels contain signal from lymph node with partial volume effect. This study looks at the effect of this low pixel count and mediate via image interpolation. No significant difference was found pre and post image interpolation for ADC values.

14:00 2983.   Longitudinal Follow-up of Kidneys from Living Donors to Their Recipients by DWI. 
Peter Vermathen1, Tobias Binser1, Harriet C Thoeny2, Chris Boesch1, Felix J Frey3, and Ute Eisenberger3
1Dept. of Clinical Research, University of Bern, Bern, Switzerland, 2Dept. of Radiology, University & Inselspital, Bern, Switzerland, 3Dept. of Nephrology, University & Inselspital, Bern, Switzerland

We performed a prospective longitudinal DWI study in living kidney donors and their corresponding recipients before and after transplantation. The unique situation in living renal allograft donation allows monitoring DWI changes in the same kidney before transplantation in the donor and after transplantation in the recipient. Over one year, all determined diffusion parameters remained remarkably stable. This constancy corresponded to GFR, which also remained stable over one year. Cortical ADC obtained in recipients after transplantation correlated significantly with those obtained the same kidney before transplantation in the donor, indicating an important impact of the original kidney status on ADC.

14:30 2984.   Diffusion-weighted MRI in the kidney pre- and post-transplantation in donor-recipient pairs 
Karl Kristopher Vigen1, Sean B Fain2, and Elizabeth A Sadowski1
1Radiology, University of Wisconsin-Madison, Madison, WI, United States, 2Medical Physics, University of Wisconsin-Madison, Madison, WI, United States

Water diffusion measured with MR diffusion weighted imaging (DWI) has been suggested as a means of studying tissue microstructure changes and can potentially be estimated using the apparent diffusion coefficient (ADC). Using donor-recipient pairs, this study aims to understand the normal response of water diffusion in kidneys undergoing transplantation compared to the remaining donor kidney.

15:00 2985.   The Effect of Fat Suppression on ADC Values in Murine Liver with Variable Degrees of Fibrosis 
Stephan William Anderson1, Jorge A Soto1, Elizabeth Tang1, and Hernan Jara1
1Radiology, Boston University Medical Center, Boston, MA, United States

Purpose: The determine if fat suppression(FS) pulses influence ADC values and whether effects vary based on degrees of fibrosis in murine liver. Methods: 3,5-dicarbethoxy-1,4-dihydrocollidine was utilized to induce hepatic fibrosis. Liver specimens were imaged using 11.7T MRI; ADC values with and without fat suppression were compared and differences correlated with hepatic fibrosis. Results: Slight differences in ADC values derived with FS were seen; poor correlation was seen between differences in ADC and degrees of fibrosis. Conclusion: The difference in ADC values with and without FS is not a confounding effect in deriving ADC values of the liver with variable fibrosis.

Wednesday May 11th
  13:30 - 15:30 Computer 4

13:30 2986.   Assesment of liver blood flow using a navigator echo respiratory gated parallel imaging technique at 1.5 T 
Loredana Sorina Truica1,2, and Ian Cameron2
1Carleton University, Ottawa, ON, Canada, 2Diagnostic Imaging - MRI research Lab, Ottawa Hospital- General Campus

IVIM measurements of normal liver at 1.5 T using a respiratory triggered DW_SS_EPI as well as a DW_SS_EPI breath hold protocol are reported. Improvements in the acquisition and analysis techniques used in this study allowed us to obtain more consistent results for the perfusion fraction, f, the diffusion coefficient, D, and the pseudo-diffusion coefficient, D*, than previous studies. Parameter maps of D and f were reflective of liver anatomy. Such maps can be useful tools in identifying tissue differences and give important insight into the organ hemodynamic system. This technique could become instrumental in the assessment and management of normal/diseased tissue in abdomen.

14:00 2987.   Diffusion-weighted MRI for the zonal characterization of liver tumors 
Mathilde Wagner1,2, Sabrina Doblas2, Jean-Luc Daire1,2, Helena Leitao1,2, Philippe Garteiser2, Valérie Vilgrain1,2, Ralph Sinkus2, and Bernard Edgar Van Beers1,2
1Radiology, Beaujon University Hospital, Clichy, France, 2Inserm U773, Centre de Recherche Biomédicale Bichat Beaujon, Clichy, France

The aim of this study was to assess if DW-MRI with separate measurements of ADC mono, ADC slow, and ADC fast could be used to differentiate between viable, fibrotic and necrotic regions within liver tumors. In contrast to ADC mono and ADC fast, ADC slow differed significantly between the three tumor regions. These results suggest that when using DW-MRI for the characterization and follow-up during treatment of liver tumors, ADC slow rather than ADC mono should be used.

14:30 2988.   The effect of Gd-DTPA on the determination of the Apparent Diffusion Coefficient in liver metastases and healthy liver tissue 
Ulrike Fasol1, Klaus Mross2, Annette Frost2, Martin Buechert1, Valerij Kiselev1, and Juergen Hennig1
1MR Development and Application Center, University Medical Center Freiburg, Freiburg, Germany, 2Tumor Biology Center, Albert-Ludwigs-University Freiburg, Freiburg, Germany

Using the Apparent Diffusion Coefficient (ADC) as a biomarker for tumors under therapy is currently under investigation. In most studies contrast enhanced imaging is included in the protocol, which poses the problem of the influence of the contrast agent on the determination of ADC. Studies performed till now were mainly focused on measurements in the brain. We present results for the effect of contrast agent on the ADC measurements in normal liver tissue and metastasis at 1.5 T.

15:00 2989.   Correlation of contrast enhancement speed of hepatic hemangiomas on gadolinium-enhanced dynamic T1-weighted images with apparent diffusion coefficient on diffusion-weighted imaging 
Dal-Mo Yang1, Hyun-Cheol Kim1, and Geon-Ho Jahng1
1Radiology, Kyung Hee University, East-West Neo Medical Center, Seoul, Korea, Republic of

Correlation of speed of hepatic hemangiomas on gadolinium-enhanced dynamic T1-weighted images with apparent diffusion coefficient on diffusion-weighted imaging

Thursday May 12th
  13:30 - 15:30 Computer 4

13:30 2990.   Motion Correction of Multiple b-values (MCMB) Diffusion-Weighted Imaging 
Yousef Mazaheri1, Richard Kinh Gian Do2, Jingbo Zhang2, Elizabeth Morris2, Oguz Akin2, and Hedvig Hricak2
1Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, United States, 2Radiology, Memorial Sloan Kettering Cancer Center

Diffusion-weighted imaging data were acquired using at multiple b-values and motion corrected with MCMB (motion correction of multi b-value). The repeatedly acquired low-b-value images were used to prospectively detect and correct for displacement during extended acquisitions. Co-registration of higher b-value images was achieved by nearest-neighbor interpolation of transformation parameters estimated at lower b-values.

14:00 2991.   Investigation of the theoretical background of the IVIM model using flow compensated DWI 
Andreas Wetscherek1, Bram Stieltjes2, Wolfhard Semmler1, and Frederik Bernd Laun1
1Medical Physics in Radiology, German Cancer Research Center, Heidelberg, Germany, 2Quantitative imaging based disease characterization, German Cancer Research Center, Heidelberg, Germany

To answer the question whether blood flow in capillaries changes its direction during a typical diffusion experiment, flow compensated diffusion weighting gradients were used for the first time in abdominal DWI of pancreas and liver. In contrast to the TE-dependent bi-exponential signal decay observed in strongly perfused organs when using bipolar gradients, the acquired data can be modeled by a mono-exponential decay and shows no dependence on TE or on the total duration of the diffusion weighting gradients. Since net flow effects are suppressed, flow compensated diffusion weighting gradients may prove useful when investigating the vascularization structure.

14:30 2992.   Assessment of position dependent eddy current distortions in DW EPI measurements: monopolar versus bipolar diffusion preparation 
Verena Ballweg1, Petros Martirosian1, Hansjörg Graf1, Hanne Wojtczyk1, and Fritz Schick1
1Section on Experimental Radiology, University Hospital Tübingen, Tübingen, Germany

Eddy currents in DW EPI sequences cause distortions which negatively influence fibre tracking for instance. Bipolar gradients reduce those distortions but lead to a longer echo time and hence to a decreased signal-to-noise ratio. However, lately gradient system quality concerning eddy currents increased making bipolar sequences maybe needless. Therefore, the distortions of DW EPI sequences with monopolar and bipolar diffusion preparations were compared at off-center positions and in the isocenter, revealing that monopolar sequences can be applied in the isocenter without considerably greater distortions. At off-center positions bp gradients are still needed.

15:00 2993.   PCATMIP: Enhancing Signal Intensity in DW-MRI 
Vinay Manjunath Pai1, Stanislas Rapacchi2, Peter Kellman1, Pierre Croisille2, and Han Wen1
1NHLBI, National Institutes of Health, Bethesda, MD, United States, 2Laboratoire CREATIS, INSA de Lyon, Lyon, France

Diffusion-weighted MRI (DWI) studies in body imaging generally lose signal intensity to physiological motion, which can adversely affect quantification and diagnosis. While averaging over multiple repetitions improves signal-to-noise ratio (SNR), it does not recover the attenuated signal intensity. We present PCATMIP, a combined Principal Component Analysis (PCA) and Temporal Maximum Intensity Projection (TMIP) approach, as a means to resolving this issue. Numerical simulations and experimental results using porcine liver data show that PCATMIP yields higher signal intensity and less variability than averaging and higher SNR than TMIP, thus achieving an optimal balance between averaging and TMIP for processing DWI data.

Electronic Posters : Body (Non-Cancer) Imaging
Click on to view the abstract pdf and click on to view the video presentation.

Monday May 9th
Exhibition Hall  14:00 - 16:00 Computer 5

14:00 2994.   Volume selective MRS of the liver for determination of hepatic lipids – is there a need for cardiac and/or respiratory triggering? 
Jürgen Machann1, and Fritz Schick1
1Section on Experimental Radiology, University Hospital Tübingen, Tübingen, Germany

1H-MRS of the liver for quantification of hepatic lipid content has evolved to one of the most applied spectroscopic applications during the past years, as hepatic lipids are involved in metabolic diseases. However, as liver is a moving organ, spectral quality might be influenced by breathing and heartbeat. There is a discussion about the best acquisition strategy regarding different triggering modalities (ECG-triggering, respiratory triggering and combination of both). This study on 5 volunteers depicts differences in spectral quality and acquisition times for all combinations of triggering. Best results regarding quality and acquisition time are achieved when subjects breathe flatly during the TR interval and are in expiration during data acquisition.

14:30 2995.   Real-time navigator gating in proton liver spectroscopy at 3T 
Andreas Hock1, Ladislav Valkovic2, Ivan Frollo2, Peter Boesiger1, Anke Henning1, and Spyros Kollias3
1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland, 2Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia, 3University Hospital of Zurich, Institute of Neuroradiology, Zurich, Switzerland

Navigator gated proton MR spectroscopy with inner volume saturation allows free breathing measurements of liver molecules while ensuring a precise location of the measured voxel. It is shown in 5 healthy volunteers that the spectral quality is improved and the variation of molecule ratios are decreased compared to measurements without gating. This technique may thus improve the quality of the diagnostic procedure of liver disease.

15:00 2996.   Metabolite Cycled Non-Water-Suppressed Spectroscopy Offers Increased Spectral Quality In Cases of Physiologic and Subject Motion 
Erin Leigh MacMillan1, Murielle Bortolotti2, Andreas Boss1, Chris Boesch1, and Roland Kreis1
1Dept. of Clinical Research, University of Bern, Bern, Bern, Switzerland, 2Dept. of Physiology, University of Lausanne, Lausanne, Switzerland

Metabolite cycled non-water-suppressed MRS enables automatic phase, frequency, and eddy-current correction of individually acquired spectra to improve SNR and lineshape of metabolite peaks. Examples from deliberate motion of the head and respiratory motion of the liver show remarkable improvement in both SNR and linewidth. The median FWHM of the liver spectra water peak was improved from 18Hz (range: 13-36Hz) to 15Hz (13-22Hz), demonstrating how this technique performs particularly well with decreasing quality of the originally measured spectra. The improved spectral quality will help make MRS more applicable in the clinic, especially in cases of subject or physiologic motion.

Tuesday May 10th
  13:30 - 15:30 Computer 5

13:30 2997.   Fast T2 Relaxometry in 1H-MRS of Hepatic Water and Fat using Short TR at 3T 
Giulio Gambarota1, Mark Tanner1, Marinette van der Graaf2, Robert Mulkern3, and Rexford D Newbould1
1Clinical Imaging Center, GSK, Imperial College, London, United Kingdom, 2Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands, 3Radiology, Children's Hospital Boston, Boston, United States

Fast measurement of both lipid and water T2 relaxation time is feasible in a single breath hold, with acquisition of several echoes and improved lipid SNR.

14:00 2998.   Quantitative estimation of the degree of macrosteatosis in living related liver donors using IDEAL gradient echo imaging 
Jeong Min Lee1, Eugene Joe1, and Joon Koo Han1
1Radiology, Seoul National University Hospital, Seoul, Seoul, Korea, Republic of

IDEAL can be used as a highly specific modality for the diagnosis of hepatic macrosteatosis as it does not have the confounding influence caused by hepatic iron deposition. IDEAL can accurately depict minimal macrovesicular hepatic steatosis within the normal range, thereby avoiding biopsy in potential living liver donors with an acceptable degree of steatosis for transplantation.

14:30 2999.   Noninvasive Quantification of Hepatic Steatosis in Rats with 1.5 T MRS and MRI: Feasibility, Early Results and Optimization 
Gaspard d'Assignies1,2, Ghislaine Fontés3,4, Louis Gaboury5, Yvan Boulanger4,6, Gilles Soulez7, Vincent Poitout3,4, and An Tang8
1Radiology, Hôpital Saint-Luc, Montreal, France, 2Beaujon Hospital, Université Paris VII, Canada, 3Montréal Diabetes Research Center, Canada, 4CRCHUM, Canada,5Department of anatomo-pathology, CHUM, Canada, 6Radiology, Hôpital Saint-Luc, Canada, 7Radiology, CRCHUM, Canada, 8Radiology, University of Montreal, Montreal, Quebec, Canada

The purpose of the study is to validate and optimize a routine 1.5T MRI method to detect and measure liver steatosis in an experimental glucolipotoxic rat model by using 1H-MR spectroscopy as the reference standard. Two 20° and 90° flip angle (FA) were applied on the dual echo in/out of phase sequence and T2* was calculated. MRI and 1H-MRS accurately distinguished steatotic from non steatotic liver. A significant correlation was found between dual-echo MRI and MRS. This correlation was higher with 90° (r = 0.749, P < 0.001) than with 20° FA (r = 0.651, P < 0.001). T2* correction did not improve the correlation with 1H-MRS.

15:00 3000.   MRI detection of glycogen in vivo in diabetic mice at 3 tesla: feasibility and initial experience 
Mina Kim1, Queenie Chan1,2, James YB Lau3, Sookja K Chung3, and Pek-Lan Khong1
1Departement of Diagnostic Radiology, The University of Hong Kong, Hong Kong, Pokfulam, Hong Kong, 2Philips Healthcare, Hong Kong, 3Department of Anatomy, The University of Hong Kong

Development of sensitive method to quantify glycogen in vivo may help to understand the pathophysiology of type-2 diabetes. In present study, we tested feasibility of in vivo glycogen detection in diabetic mouse model using chemical exchange saturation transfer imaging. Our results suggest that in vivo CEST quantification in mouse liver is feasible in a clinical scanner.

Wednesday May 11th
  13:30 - 15:30 Computer 5

13:30 3001.   Longitudinal Tracking of Adiposity in a Canine Model of Insulin Resistance 
Edward Brian Welch1,2, Johan Berglund3, Joel Kullberg3, Katie Colbert Coate4, Phil Williams4, Alan Cherrington4, and Malcolm J Avison1,2
1Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 2Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States, 3Department of Radiology, Uppsala University, Uppsala, Sweden, 4Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, United States

Animal models in which whole body adiposity can be manipulated and the size of specific adipose tissue (AT) depots measured longitudinally and non-invasively, can help improve our understanding of the role of specific AT depots in the pathogenesis of obesity-associated metabolic diseases. In this abstract, we describe the adaptation of a whole body fat-water MR imaging acquisition and automated analysis pipeline, initially validated in human volunteers, for whole-body FWI in dogs. We demonstrate the utility of this pipeline by following the changes in lean and AT volume in dogs placed on an obesogenic high-fat, high-fructose diet known to increase insulin.

14:00 3002.   Test-Retest Reproducibility of Whole-body Fat Water Imaging at 3 Tesla Compared to DEXA 
Edward Brian Welch1,2, Malcolm J Avison1,2, Kevin D Niswender3, Johan Berglund4, Joel Kullberg4, Lars Johansson4, Morten Bruvold5, and Heidi J Silver3
1Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 2Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States, 3School of Medicine, Vanderbilt University, Nashville, TN, United States, 4Department of Radiology, Uppsala University, Uppsala, Sweden, 5MR Clinical Science, Philips Healthcare, Best, Netherlands

Whole-body MRI has great potential for quantifying the amount, type and distribution of adipose tissue to help better understand its metabolic consequences. Multi-gradient-echo MR acquisitions have been successfully used to quickly acquire whole-body fat-water imaging data sets. Dual energy x-ray absorptiometry (DEXA) is widely used in studies of body composition, but few direct comparisons of the performance of fat-water MR imaging (FWMRI) to DEXA are available, especially for 3T FWMRI. Here we present test-retest results of scanning 12 obese female subjects using a 3T mFFE whole-body FWMRI sequence as well as DEXA.

14:30 3003.   Quantitative Analysis of Fat Distribution using Whole-Body Magnetic Resonance Imaging 
Julien Dinkel1, Diana Wald2, Heinz-Peter Schlemmer3, Hans-Peter Meinzer4, Rudolf Kaaks5, and Stefan Delorme3
1Radiology, German Cancer Research Center, Heidelberg, Germany, 2Medical and Biological Informatics, German Cancer Research Center, 3Radiology, German Cancer Research Center, 4Medical and Biological Informatics, 5Cancer Epidemiology, German Cancer Research Center

The purpose of this study was to evaluate a semiautomatic method to quantify the distribution of visceral and non visceral internal fat acquired using the two point Dixon technique from whole-body MRI data. We performed MR imaging on 30 subjects using a 1.5T system using a 3d-Dixon-VIBE sequence. Signal strength changes within the 3D volume due to variation in coil sensitivity were corrected with a normalization algorithm. Full automated correction of the Dixon-mismatch artifacts were performed successfully. Automated segmentation quantifying the distribution of visceral and non visceral fat were done and assessed as successful by an experienced radiologist.

15:00 3004.   Correlation of lipid profile and insulin sensitivity with body fat evaluated using MRI, Dual Energy X-ray Absorptiometry and Bioimpedance 
Ankur Poddar1, and Rama Jayasundar1
1NMR, All India Institute of Medical Sciences, New Delhi, Delhi, India

Correlation of lipid profile and insulin sensitivity with body fat evaluated using MRI, Dual Energy X-ray Absorptiometry and Bioimpedance A.Poddar 1, R. Jayasundar 2, A.C. Ammini 3, A. K. Mukhopadhyaya 4 Departments of Biotechnology1, NMR2, Endocrinology3, Lab Medicine4, All India Institute of Medical Sciences, New Delhi, India. In this study, body fat assessed using MRI, Dual energy x-ray absorptiometry (DEXA) and Bio-impedance analysis (BIA) methods are correlated individually with biochemical parameters such as lipid profile, insulin sensitivity, BMI & BMR and compared. These biochemical parameters are considered risk factors for diabetes, obesity, etc. The data indicates that fat mass evaluated using all the three techniques (MRI, DEXA and BIA) correlated well with insulin sensitivity and BMI and can be used interchangeably. However, only MRI evaluated fat mass correlated well with cholesterol and MRI had the additional advantage of giving information on fat distribution in the whole body.

Thursday May 12th
  13:30 - 15:30 Computer 5

13:30 3005.   Determination of ATP synthesis exchange rates in human liver and skeletal muscle using 31P magnetization transfer 
Tania Buehler1, Andreas Boss1, Roland Kreis1, and Chris Boesch1
1Dept. of Clinical Research, University of Bern, Bern, Switzerland

The metabolic syndrome, which includes insulin resistance (IR), is a risk factor for cardiovascular diseases with epidemic dimensions. It is hypothesized that impaired mitochondrial activity could be a cause of IR. ATP synthesis exchange rates determined by 31P MRS allow a non-invasive estimation of mitochondrial activity. Several human studies exist for skeletal muscle, but only one for liver. Two methods (31P saturation (ST) and inversion transfer (IT)) have been implemented in combination with volume selection based on saturation bands. In this study the two methods for a determination of ATP synthesis exchange rates are compared in skeletal muscle and liver.

14:00 3006.   Regional variability in triglyceride composition of adipose tissue measured by 1H MRS 
Gavin Hamilton1, Michael S Middleton1, Takeshi Yokoo1, and Claude B Sirlin1
1Department of Radiology, University of California, San Diego, San Diego, California, United States

The multi-peak structure of the fat 1H MR Spectrum allows non-invasive estimation of triglyceride composition in adipose tissue in vivo. The study compares variability in triglyceride composition of three different abdominal adipose tissue depots. We see statistically different triglyceride compositions in the three abdominal adipose tissue depots.

14:30 3007.   Influence of Type 2 Diabetes on Intramyocellular Lipids among Patients with Chronic Kidney Disease 
Jimin Ren1, Manisha Shah2, Maram Museitif2, Lynne Roetzer2, A Dean Sherry1,3, Craig R Malloy1,2, and Devasmita Choudhury2
1Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States, 2VA North Texas Health Care System, 3Department of Chemistry, University of Texas at Dallas, Richardson, Texas

Chronic kidney disease (CKD) and type 2 diabetes (T2D) are both highly prevalent and complex disorders. While T2D may cause CKD; CKD also independently causes insulin resistance. Increased intramyocellular lipids (IMCL) have been associated with insulin resistance and diabetes but the role of the compartmental distribution of lipids in normal physiology and disease is still debated. This study was designed to test the hypothesis that patients with T2D and CKD have higher levels of IMCL compared to patients with CKD but without overt T2D. Surprisingly, the results showed that IMCL was not significantly different in diabetic vs. nondiabetic CKD patients.

15:00 3008.   Look-Locker MRI measurements of relaxation rate after manganese labeling of pancreatic β cells detect increments in disease progression in a mouse model of type 1 diabetes 
Patrick Antkowiak1, Brian Stevens2, Marcia McDuffie2, and Frederick H Epstein3
1Biomedical Engineering, University of Virginia, Charlottesville, Virginia, United States, 2Microbiology, University of Virginia, 3Radiology, University of Virginia

Pancreatic β cells secrete insulin and maintain blood glucose homeostasis; in type 1 diabetes mellitus (T1D), β cell function and mass decline, with potentially severe complications. Noninvasive imaging to detect this decline would be important for both pre-clinical and clinical studies. We used Look-Locker MRI to measure the pancreatic relaxation rate R1 after injection of MnCl2, which labels functional β cells, and applied this to a mouse model of T1D characterized by a graded loss of functional β cell mass. We measured a decline in pancreatic R1 concurrent with the incidence of T1D and decline in functional β cell mass.

Electronic Posters : Body (Non-Cancer) Imaging
Click on to view the abstract pdf and click on to view the video presentation.
Body Applications of Contrast Media & Bowel MRI

Monday May 9th
Exhibition Hall  14:00 - 16:00 Computer 6

14:00 3009.   Evaluation of positive contrast around SPIO-loaded polymer threads for surgical mesh delineation by MRI 
Hank C.W. Donker1, Nils A. Krämer1, Jens Otto2, Ioana Slabu3, Martin Baumann3, Uwe Klinge2, and Christiane K. Kuhl1
1Department of Diagnostic Radiology, RWTH Aachen University, Aachen, NRW, Germany, 2Department of Chirurgy, RWTH Aachen University, Aachen, NRW, Germany,3Helmholtz Institute for Applied Medical Engineering, RWTH Aachen University, Aachen, NRW, Germany

Surgical textile mesh implants for abdominal hernia repair are hard to delineate in MRI. To improve MR-visualization, superparamagnetic iron oxides (SPIO) were implanted in the mesh polymer base material. SPIO generate magnetic susceptibility gradients. To discriminate SPIO induced voids from proton-free structures positive contrast susceptibility imaging was developed. Here 4 ways to generate positive contrast from susceptibility gradients were compared: IRON, FLAPS, white-marker imaging and SGM. The acquisition of a gradient echo image with a calculated Short Term Fourier Transform Susceptibility Gradient Map image is to be preferred for positive contrast imaging of SPIO loaded hernia meshes.

14:30 3010.   High-resolution interstitial MR lymphography for the diagnosis of sentinel lymph nodes: Inhomogeneous distribution of SPIO within non-malignant lymph nodes 
Daisuke Suzuki1,2, Masayuki Yamaguchi1, Toshihiro Furuta1,3, Kohki Yoshikawa2, and Hirofumi Fujii1
1Functional Imaging Division, National Cancer Center Hospital East, Kashiwa, Chiba, Japan, 2Graduate Division of Health Sciences, Komazawa University, Setagaya, Tokyo, Japan, 3Department of Radiology, The Tokyo University Hospital, Tokyo, Japan

Since the presence of sentinel lymph nodes (SLNs) metastasis predicts a poor prognosis, the diagnosis of SLN metastasis is clinically important. MR lymphography by means of the interstitial administration of superparamagnetic iron oxide (SPIO) is one of the techniques that can sensitively detect SLNs based on the signal reduction by SPIO trapped by macrophages. To our knowledge, the intra-lymph node distribution of subcutaneously administered SPIO has not been fully understood. In this study, we demonstrated the inhomogeneous distribution of interstitially administered SPIO within regional lymph nodes of mice using high-resolution MRI and Prussian blue-stained specimens

15:00 3011.   Fitting DCE-MRI data in the liver with a dual-inlet model: choice of venous and arterial delay parameters 
Steven Sourbron1, Wieland Sommer2, Christoph J Zech2, Maximilian F Reiser2, and Karin A Herrmann2
1Division of Medical Physics, University of Leeds, Leeds, United Kingdom, 2Department of Clinical Radiology, University of Munich, Munich, Germany

The choice of arterial and venous delay times in DCE-MRI of the liver has a strong effect on the measured parameters. In this study a number of alternative methods are applied to patient data and compared. Results show that an arterial delay time is necessary to obtain a good fit to the data, but including an additional venous delay causes unstable and overestimated perfusion values. It is concluded that DCE-MRI data in the liver are best analysed by fitting an arterial delay, and assuming that the venous delay is zero.

15:30 3012.   Initial experiences evaluating the hepatic arterial buffer response with DCE-MRI in healthy rats at 9.4T 
Manil Chouhan1, Shonit Punwani1, Alan Bainbridge2, Nathan Davies3, Raj Mookerjee3, Rajiv Jalan3, and Stuart Taylor1
1Centre for Medical Imaging, University College London, London, London, United Kingdom, 2Department of Medical Physics, University College London Hospitals NHS Trust,3Institute of Hepatology, University College London

Feasibility of DCE-MRI for liver haemodynamic assessment before and after modulation of portal venous flow is demonstrated, with presentation of preliminary data.

Tuesday May 10th
  13:30 - 15:30 Computer 6

13:30 3013.   Clinical Feasibility of High-Resolution Navigator-Gated 3D T1w Hepatobiliary MRI with Gd-EOB-DTPA Enhancement 
Alan De Lun Xu1, Anja C Brau2, Yuji Iwadate2, Jarrett Rosenberg1, Shreyas Vasanawala1, and Robert Herfkens1
1Radiology, Stanford University, Stanford, CA, United States, 2GE Healthcare

Conventional contrast-enhanced 3D T1w hepatic imaging requires serial breath-hold acquisitions to capture the contrast dynamics, inherently limiting spatial resolution and image quality. The hepatobiliary-specific contrast agent Gd-EOB-DTPA offers a prolonged time window of contrast-enhancement over which data can be acquired. This work evaluates the clinical feasibility of using a navigator-gated 3D T1w sequence to improve the spatial resolution and image quality of Gd-EOB-DTPA-enhanced hepatobiliary imaging compared to conventional breath-hold imaging.

14:00 3014.   Balanced MR Cholangiopancreatography with Motion-Sensitized Driven-Equilibrium: Feasibility of Post-contrast Biliary Examination with Gadolinium Ethoxybenzyl Diethylene Triamine Pentaacetic Acid (Gd-EOB-DTPA) 
Tomohiro Nakayama1, Akihiro Nishie1, Takashi Yoshiura1, Yoshiki Asayama1, Kousei Ishigami1, Daisuke Kakihara1, Yukihisa Takayama1, Makoto Obara2, and Hiroshi Honda1
1Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan, 2Philips Electronics Japan

In this study, a balanced steady-state free precession (SSFP) sequence with motion-sensitized driven-equilibrium (MSDE) preparation was used as an alternative technique for magnetic resonance cholangiopancreatography (MRCP).@@T2-weighted MRCP was associated with poor visualization of the biliary systems due to excreted Gd-EOB-DTPA, as previously reported. Use of MSDE-balanced MRCP resulted in higher CNR and better visualization of biliary structures than T2-weighted MRCP. Moreover, problematic vesselfs signals, such as PV and HV, were sufficiently suppressed by MSDE technique.@@In conclusion, we demonstrated the usefulness of MSDE-balanced MRCP sequenced in Gd-EOB-DTPA post-contrast study.

14:30 3015.   Diagnosis of FNH: Comparison of Gd-EOB-DTPA with Gd-BOPTA, Preliminary Results from a Multicentric US Study. 
Christine Iseman1, Bachir Taouli1, Rajan T Gupta2, John Leyendecker3, and Elmar Merkle2
1Mount Sinai School of Medicine, New York, NY, United States, 2Duke University, Durham, NC, United States, 3Wake Forest University, Winston-Salem, NC, United States

In this study, we report preliminary results from a US multicentric study, comparing qualitatively and quantitatively Gd-EOB-DTPA and Gd-BOPTA for diagnosis of FNH. 23 FNHs were assessed in 11 preliminary patients. Lesion conspicuity was equivalent for both contrast agents at all phases. Quantitative enhancement was significantly higher at the arterial and portal venous phases for Gd-BOPTA, and higher at the hepatobiliary phase for Gd-EOB-DTPA. These preliminary results indicate advantage for BOPTA at the dynamic phase, and advantage for EOB at the hepatobiliary phase.

15:00 3016.   The First Human Whole Body Pharmacokinetic Minimal Model for the Liver Specific Contrast Agent Gd-EOB-DTPA 
Mikael Fredrik Forsgren1,2, Olof Dahlqvist Leinhard1,3, Gunnar Cedersund2,4, Nils Dahlström1,3, Örjan Smedby1,3, Torkel B Brismar5, and Peter Lundberg3,6
1Department of Medical and Health Sciences, Division of Radiological Sciences, Linköping University, Linköping, Sweden, 2Department of Clinical and Experimental Medicine, Diabetes and Integrated Systems Biology, Linköping University, Linköping, Sweden, 3Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden, 4School of Life Sciences, Freiburg Institute of Advanced Sciences, Freiburg, Germany, 5Department of Radiology, Karolinska University Hospital, Stockholm, Sweden, 6Department of Radiation Physics, CKOC, University Hospital of Linköping, Linköping, Sweden

Clinical dynamic contrast-enhanced MRI examinations of the human liver can be analyzed in detail using tissue models. Our aim was to devise the first physiologically correct minimal model that describes the most important routes of contrast agent flux. Based on established pharmacokinetic equations incorporated into a system of ordinary differential equations, the model has a significant potential for gaining a better understanding of the contrast agent behaviour in the human body. We believe that it is possible, in a Bayesian modeling framework, to use the model on individual patient data, thereby increasing the information obtained from clinical examinations.

Wednesday May 11th
  13:30 - 15:30 Computer 6

13:30 3017.   Magnetization Transfer Detects Changes in Intestinal Fibrosis after Anti-TNFlower case Greek alpha 
Scott D Swanson1, Jeremy Adler2, Phyllissa Schmiedlin-Ren3, Kinan Rahal3, Laura Reingold3, and Ellen M Zimmermann3
1Department of Radiology, University of Michigan, Ann Arbor, MI, United States, 2Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, United States, 3Department of Internal Medicine-Gastroenterology, University of Michigan, Ann Arbor, MI, United States


14:00 3018.   T2 relaxometry to assess inflammation and fibrosis in an acute and chronic murine model of inflammatory bowel diseases 
Tom Dresselaers1, Christine Breynaert2, Gert Van Assche2, and Uwe Himmelreich1
1Biomedical NMR Unit/ MoSAIC, K.U.Leuven, Leuven, Brabant, Belgium, 2Division of Gastroenterology, K.U.Leuven, leuven, Brabant, Belgium

In human colon disease, the value of MRI and CT enterography as a non-invasive assessment tool of transmural inflammation and extraluminal complications is increasingly recognized. However, data on MR imaging as a screening tool to study murine ileitis or colitis are limited. In this study the feasibility of using T2-weighted imaging and T2 maps to distinguishing between a DSS induced acute and chronic murine colitis model was evaluated. T2 values are markedly different between the control, acute and chronic group. This is confirmed by histology which shows more fibrosis in the chronic versus acute model.

14:30 3019.   Optimising oral contrast agents for interactive neonatal gut imaging 
Owen John Arthurs1, Martin John Graves1, Ilse Joubert1, and David John Lomas1
1Radiology, University of Cambridge, Cambridge, Cambridgeshire, United Kingdom

The optimal contrast medium for neonatal gut MR imaging is unclear. Here, we investigate the relative T1 properties of several different potential agents to provide optimal signal. We then tested a variable IR pulse during interactive SSFSE imaging to null existing bowel fluid and demonstrate feasibility. An optimal in-vitro TI of 500 - 800ms gave maximal signal difference between pineapple juices and milk, but in-vivo this was 1000 ms. Application of an optimally timed IR pulse can allow for improved contrast medium imaging in this sensitive population.

15:00 3020.   Contrast-enhanced MR enterography as a stand-alone tool to evaluate Crohn’s disease in pediatric population. 
Bradley Spieler1, Nicole Hindman1, Caludia Reuben Seuss1, Alec J Megibow1, Joseph Levy2, Kerry Zabriskie2, Daniel Sahlein1, Rafael Rivera1, and Sooah Kim1
1Radiology, New York University, New York, NY, United States, 2Pediatric Gastroenterology, New York University, New York, NY, United States

MR imaging of the pediatric abdomen can be challenging, often secondary to inability to tolerate long scan times. Twenty five pediatric patients (mean age 11.2 years) with Crohn’s disease referred for MR enterography at 1.5 T were evaluated. Two radiologists reviewed post contrast images of MRI during the first session and all images including pre- and post contrast sequences during the second session. The intestine was divided into 10 segments. The readers evaluated the presence or absence of disease in regard to the presence of active inflammation using a five-point grading system. Sensitivity, specificity, PPV, NPV, and accuracy for diagnosing definite active inflammation using post contrast images alone were 83.3%, 86.9%, 89.3%, 80%, and 84.9%, respectively. In all five of the false negative cases there was a disagreement in at least one bowel segment with respect to the presence or absence of abscess and/or sinus tracts which was confirmed on non-contrast images (HASTE without fat suppression).

Thursday May 12th
  13:30 - 15:30 Computer 6

13:30 3021.   Simultaneous assessment of gastric secretion, mixing and emptying during free breathing 
Jelena Curcic1, Matthias Sauter2, Werner Schwizer2, Peter Boesiger1, and Andreas Steingoetter1,2
1Institute for Biomedical Engineering, University and ETH, Zurich, Zurich, Switzerland, 2Division of Gastroenterology and Hepatology, University Hospital Zurich, Zurich, Switzerland

Gastric emptying, distention, intragastric secretion and mixing are important factors in pathogenesis of gastro-intestinal (GI) diseases such as gastro-esophageal reflux disease (GERD). A formerly described method, for simultaneous T1 mapping and imaging was optimized and validated for free breathing gastric imaging. The optimized sequence (GOLD) was used in-vivo to simultaneously detect intragastric secretion and mixing as well as gastric emptying during free breathing. This pilot study shows the feasibility of the GOLD sequence to detect multiple gastric parameters in one single free breathing period of maximally 2 min and emerges as a versatile tool for diagnostic GI MRI.

14:00 3022.   Quantitative assessment of small bowel motility by nonrigid registration of dynamic MR images 
Freddy Odille1, Alex Menys2, Asia Ahmed2, Shonit Punwani2, Stuart Taylor2, and David Atkinson1
1Centre for Medical Image Computing, University College London, London, United Kingdom, 2Centre for Medical Imaging, University College London, London, United Kingdom

Small bowel motility assessment by dynamic MRI is of increasing interest for the clinical management of enteric disorders such as Crohn’s disease. A postprocessing technique is described for the automated assessment of bowel motility. The technique jointly registers 2D dynamic images (nonrigidly) and models local intensity changes due to through-plane motion or flow. Validation was performed by drawing various small bowel regions in 10 patients with known or suspected Crohn’s disease. We assessed the performance of the registration (manual versus automatically propagated markers) as well as the agreement between automated motility measures with expert grading of the motility.

14:30 3023.   Defining the mode of action of Loperamide and Loperamide plus Simethicone using an MRI model of acute diarrhoea 
Elisa Placidi1, Luca Marciani2, Caroline L Hoad1, Klara C Garsed2, Susan E Pritchard1, Eleanor F Cox1, Carolyn Costigan3, Robin C Spiller2, and Penny A Gowland1
1SPMMRC, University of Nottingham, Nottingham, United Kingdom, 2Nottingham Digestive Diseases Centre Biomedical Research Unit, Nottingham, United Kingdom, 3Brain and Body Centre, University of Nottingham, Nottingham, United Kingdom

MRI was used to investigate the mode of action of anti-diarrheal drugs, loperamide and loperamide + simethicone, using a model of acute diarrhoea based on a mannitol drink. 18 healthy volunteers were imaged on a 1.5 T Philips Achieva scanner with several sequences up to 5 hours after the mannitol drink, to assess changes in the gut in terms of water content, volume, T2 and image signal intensity. Differences between the three conditions have been quantified, proving that the MRI technique optimised is efficient to investigate the response of the gut to drugs.

15:00 3024.   Real-time Imaging and Reconstruction of the Small Bowels Based on Golden Ratio Radial and Regularized SENSE MRI 
Lau Brix1,2, Steffen Ringgaard2, Brian Stausbøl-Grøn2, Bodil Ginnerup Pedersen2, Yasmina Berber3, Mario Ries3, and Thomas Sangild Sørensen4,5
1Department of Clinical Engineering, Aarhus N, Region Midt, Denmark, 2MR-Centre, Aarhus University Hospital, Skejby, Aarhus N, Region Midt, Denmark, 3Laboratoire IMF, Centre National de la Recherche Scientifique/Universite Bordeaux 2, France, 4Department of Computer Science, Aarhus University, Denmark, 5Institute of Clinical Medicine, Aarhus University, Denmark

The aim of this project was to implement a real-time data and reconstruction system for imaging of the bowel by using a constant azimuthal profile based on the Golden Ratio. The reconstruction gave the operator a unique possibility to interactively reconstruct images with an optimal compromise between a true temporal resolution and a sliding window reconstruction in real-time. This study demonstrates that real-time images of the bowel may improve the diagnosis and documentation of patients with Crohn’s disease, bowel stenosis or altered bowel motility and is a step toward using MRI for imaging moving organs on-line in real-time.

Electronic Posters : Body (Non-Cancer) Imaging
Click on to view the abstract pdf and click on to view the video presentation.
Pulmonary Structure & Function with Hyperpolarized Gas & Proton MRI

Monday May 9th
Exhibition Hall  14:00 - 16:00 Computer 7

14:00 3025.   Modeling Hyperpolarized 129Xe Bolus Passage for Quantification of Pulmonary Blood Flow 
Harald E. Möller1,2, Zackary I. Cleveland2, Laurence W. Hedlund2, John Nouls2, Matthew Freeman2,3, Yi Qi2, and Bastiaan Driehuys2
1Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, 2Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States, 3Graduate Program in Medical Physics, Duke University, Durham, NC, United States

Information on pulmonary perfusion can be obtained by from experiments involving intravenous injection of hyperpolarized (HP) 129Xe. Signal curves recorded in rats during bolus transport through the gas-exchange region can be fitted to a model that assumes delayed bolus arrival and an exponential transport function to account for dispersion effects. Quantitative results are consistent with expected values for the cardiac output and transit times in the lung.

14:30 3026.   A simple model of gas exchange in the lung for hyperpolarized Xe129 
Yulin V Chang1
1Mechanical Engineering, Washington University, St. Louis, MO, United States

We present in this a work a simple model of gas exchange in the lung for hyperpolarized Xe129. This model expresses the two dissolved-xenon signal amplitudes in the lung in terms of several important pulmonary parameters, including surface area-to-volume ratio, air-blood barrier thickness, capillary blood transit time, etc. It provides a means to quantify not only the microstructure, but the physiology and function of the lung. It can potentially be used in diagnosing a variety of related pulmonary diseases.

15:00 3027.   Optimized diffusion time for long-time-scale Helium-3 diffusion MRI 
Chengbo Wang1, John P Mugler, III1,2, Eduard E de Lange1, and Talissa A Altes1
1Radiology, University of Virginia, Charlottesville, VA, United States, 2Biomedical Engineering, University of Virginia, Charlottesville, VA, United States

Global long-time-scale helium-3 ADC values as a function of diffusion time were measured in 29 healthy volunteers and 14 subjects with COPD. The percentage difference in group mean ADC versus diffusion time had a well-defined maximum at a diffusion time of approximately 1 s, suggesting that this diffusion time affords the best ability to discriminate COPD and healthy subjects. Furthermore, the percentage difference between the two groups at the long-time scale (110%-150%) was much greater than that found at the short-time-scale (commonly, 20%-100%), which supports the premise that long-time-scale diffusion is more sensitive to COPD than short-time-scale diffusion.

15:30 3028.   Non-linear image registration of 3He lung diffusion MRI acquired at different inflation states, exemplified by alveolar ventilation maps 
Torsten Dorniok1, Peter Magnusson1, Frederik Hengstenberg1,2, Sergei Karpuk3, Jorgen Vestbo2, Per Åkeson1, and Lise Vejby Søgaard1
1Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital, Hvidovre, Denmark, 2Department of Cardiology and Respiratory Medicine, Copenhagen University Hospital, Hvidovre, Denmark, 3Institute of Physics, University of Mainz, Mainz, Germany

A non-linear image registration method was used to co-register hyperpolarized 3He diffusion MRI data acquired at different stages of inflation. The method was validated using synthetic data and data from healthy volunteers. ADC values in the original and registered maps were compared regionally to assess if the transformation had any considerable effect on the values.

Tuesday May 10th
  13:30 - 15:30 Computer 7

13:30 3029.   Functional mapping of regional airway obstruction and gas trapping in 3D using dynamic HP He-3 MRI 
Jionghan Dai1, Eric T Peterson2, James H Holmes3, Robert V Cadman1, Ronald L Sorkness4, and Sean B Fain1,5
1Medical Physics, University of Wisconsin - Madison, Madison, Wisconsin, United States, 2Biomedical Engineering, University of Wisconsin - Madison, Madison, Wisconsin, United States, 3Global Applied Science Laboratory, GE Healthcare, Madison, Wisconsin, United States, 4pharmacy, University of Wisconsin - Madison, Madison, Wisconsin, United States, 5Radiology, University of Wisconsin - Madison, Madison, Wisconsin, United States

Noble gas MRI enables high contrast to noise dynamic imaging during respiratory maneuvers. A model of gas in-flow using linear system theory to deconvolve the dispersion at the trachea provides maps that are analogous to gas flow, while washout delay during forced exhalation provides maps of gas trapping. In this work the feasibility of these modeling approaches is evaluated in adults and children with known obstructive lung disease.

14:00 3030.   Validation of Hyperpolarized 3Helium MRI in probing Regional Ventilation: A quantitative assessment against MDCT based local air volume changes (AVC) 
Ahmed Fathi Halaweish1,2, Youbing Yin3, Daniel R. Thedens1, Ching-Long Lin3, Edwin JR vanBeek4, and Eric A Hoffman1,2
1Department of Radiology, University of Iowa, Iowa City, IA, United States, 2Department of Biomedical Engineering, University of Iowa, Iowa City, IA, United States,3Department of Mechanical & Industrial Engineering, University of Iowa, Iowa City, IA, United States, 4Queen's Medical Research Institute, University of Edinburgh, Edinburgh, Scotland

Hyperpolarized 3Helium MRI has enabled probing of ventilation distribution (static ventilation) and the underlying microstructure (apparent diffusion coefficients). We have successfully evaluated these techniques against regional ventilation measures based on local air volume changes, obtained from matching FRC to TLC MDCT scans. A strong positive correlation between the techniques was observed, as well as a strong fit of the regression line between the two, when assessed on a whole or left & right lung basis. Differences arise as a function of gas density, such that 3Helium distributions are higher in the ventral portions when compared against the MDCT estimates.

14:30 3031.   Development of a Three-Dimensional Visualization and Atlasing Tool for Pulmonary Gas Distribution from Hyperpolarized 3He Magnetic Resonance Imaging 
Andrew Wheatley1, Usaf Aladl1, Igor Gyacskov1, Aaron Fenster1,2, and Grace Parraga1,2
1Imaging, Robarts Research Institute, London, Ontario, Canada, 2Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada

Until the emergence of hyperpolarized 3He MRI, it has been difficult to quantify and visualize the structure/function relationships of the lung with high spatial and temporal resolution. Our objective was to generate, from static ventilation 3He MRI images of COPD, three-dimensional volumetric lung models that incorporate k-means clustering of differential pixel intensities across the lung that represent partial, fully and non-ventilated regions. We developed software and a visualization environment to generate a set of fully rotational 3D surfaces of the regional ventilation patterns for individual COPD subjects and an image-based lung atlas that combines the functional features of 55 COPD subjects.

15:00 3032.   Improved Compressed Sensing reconstruction and optimised sampling patterns for very fast acquisition of Hyperpolarised 3He images 
Salma Ajraoui1, Steven Parnell1, Juan Parra-Robles1, Robert Ireland1, and Jim Wild1
1University of Sheffield, Sheffield, United Kingdom

Compressed Sening reconstruction of lung 3He images is improved through the introduction of prior knowldge. Here coregistered 1H MRI image and the knowledge of the hyperpolarised gas depolarisation through the k-space filter are used for a more accurate reconstruction at higher reduction factor.

Wednesday May 11th
  13:30 - 15:30 Computer 7

13:30 3033.   T2* Measurements of 3.0 T MRI with Ultra-Short TE: Capabilities of Pulmonary Functional Assessment and Clinical Stage Classification in Smokers 
Yoshiharu Ohno1,2, Hisanobu Koyama1, Takeshi Yoshikawa1, Nobukazu Aoyama2, Daisuke Takenaka1, Keiko Matsumoto3, Masaya Takahashi4, Makoto Obara5, Marc van Cauteren5, and Kazuro Sugimura1
1Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, 2Radiology, Kobe University Hospital, Kobe, Hyogo, Japan, 3Radiology, Yamanashi Hospital of Social Insurance, Kofu, Yamanashi, Japan, 4Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Houston, TX, United States, 5Philips Healthcare, Tokyo, Japan

Recently, several investigators have tried to determine the utility of regional T2* measurement in the lung for assessment of pulmonary diseases in animal studies. We hypothesized that direct T2* measurement in the lung at 3.0 T MR system has a potential role to play as a method for pulmonary functional loss assessment and clinical stage classification as well as thin-section MDCT. The purpose of this study was to determine the capability of pulmonary MR imaging with ultra-short TEs (UTEs) in a 3.0 T system for pulmonary functional assessment and clinical stage classification in smokers.

14:00 3034.   3D Pulmonary Perfusion MRI with Whole-Chest Coverage, High Temporal and Isotropic Spatial Resolution 
Kang Wang1, Frank Korosec1,2, Mark Schiebler2, Christopher Francois2, Scott Reeder2,3, Thomas Grist2, Reed Busse4, James Holmes4, Jean Brittain4, Nathan Artz1, Sean Fain1,3, and Scott Nagle2
1Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, 2Radiology, University of Wisconsin-Madison, Madison, WI, United States, 3Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States, 4Applied Science Lab, GE Healthcare, Madison, WI, United States

MR pulmonary perfusion is well suited for studying the pulmonary circulation and understanding the physiology and pathology of the lung. However, MR pulmonary perfusion has been challenging due to the requirements for large spatial coverage, high temporal resolution, and high spatial resolution. The purpose of this study is to demonstrate the feasibility of obtaining high isotropic spatial resolution 3D dynamic pulmonary perfusion images of the whole chest with very high temporal resolution. The technique combines a previously developed Interleaved Variable Density sampling method with parallel imaging and Cartesian HYPR reconstruction.

14:30 3035.   Automated Airway Lumen Segmentation and Characterization in Patients with Tracheomalacia: a Feasibility Study 
Piotr A Wielopolski1, Pierluigi Ciet2,3, Rashindra Manniesing4, Sandra Lever2, Martin Lequin1, Gabriel Krestin1, and Harm A.W.M. Tiddens1,2
1Radiology, Erasmus Medical Center, Rotterdam, Netherlands, 2Pulmonology, Erasmus Medical Center, Sophia Children Hospital, Rotterdam, Netherlands, 3Radiology, Department of Medical-Diagnostic Sciences and Therapies, University of Padua, Padua, Italy, 4Department of Informatics and Radiology, Erasmus Medical Center, Rotterdam, Netherlands

Tracheomalacia is an excessive narrowing of the intra-thoracic part of the trachea such that the airway is softer and more susceptible to collapse. We demonstrate a suitable acquisition scenario using static and dynamic 3D MRI sequences with sufficient temporal and spatial resolution to provide good morphological information and visualization of dynamic events in the central airways. We evaluate a segmentation and dynamic analysis tool to compute the cross-sectional areas of the central airways down to the 2nd generation branching and detect airway narrowing during the respiratory manouvers. We conclude that cine-MRI is a feasible non-invasive radiation free alternative for bronchoscopy.

15:00 3036.   Comparative Study of SSFP lung MRI at 1.5T with High Resolution Computed Tomography in patients with Interstitial Lung Fibrosis 
Smitha Rajaram1, Andy James Swift1,2, David Capener1, Robin Condliffe3, Charlie Elliot3, Judith Hurdman3, Christine Davies4, Catherine Hill4, David G Kiely3, and Jim M Wild1
1Academic unit of Radiology, University of Sheffield, Sheffield, yorkshire, United Kingdom, 2NIHR Cardiovascular Biomedical Research Unit, Sheffield, United Kingdom,3Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield, 4Department of Radiology, Royal Hallamshire Hospital, Sheffield

Interstitial lung disease is characterised by inflammation and scarring of the pulmonary interstitium leading to increased signal from the diseased lung tissue. The purpose of our study was to compare 1.5 SSFP MRI of the lung parenchyma with high resolution computed tomography (HRCT), which is considered as the ‘gold standard’ imaging modality in assessment of patients with interstitial lung disease. MR lung imaging has good specificity and sensitivity for diagnosing pulmonary fibrosis. However our results show that lung MRI has a poor sensitivity (78.5%) for identifying mild degree of pulmonary fibrosis but high sensitivity for severe disease.

Thursday May 12th
  13:30 - 15:30 Computer 7

13:30 3037.   Accelerated Whole-Lung Specific Ventilation Imaging in Large Species with Hyperpolarized Gas MRI 
Kiarash Emami1, Hooman Hamedani1, Yinan Xu1, Stephen J. Kadlecek1, Yi Xin1, Puttisarn Mongkolwisetwara1, Harrila Profka2, Masaru Ishii3, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States,3Otolaryngology–Head & Neck Surgery, Johns Hopkins University, Baltimore, MD, United States

The accelerated acquisition scheme for imaging specific ventilation effectively reduced the total imaging time by a factor of two as implemented in mechanically ventilated Yorkshire pigs. In addition to retaining the breathing pattern closer to normal conditions, this technique is less sensitive to the accumulative RF effect, as well as O2-induced depolarization of 3He, which collectively improve the accuracy of r measurements, and encourages transition to voluntarily breathing human subjects.

14:00 3038.   Quantification of Regional Lung Microstructure Response to Positive End-Expiratory Pressure by Hyperpolarized Gas MRI in Surfactant-Deficient Rats 
Maurizio F. Cereda1, Kiarash Emami2, Stephen J. Kadlecek2, Yi Xin2, Puttisarn Mongkolwisetwara2, Harilla Profka2, Amy Barulic2, Stephen Pickup2, Nicholas N. Kuzma2, Masaru Ishii3, Hooman Hamedani2, Benjamin M Pullinger2, Rajat Ghosh2, Jennia Rajaei2, Clifford S. Deutschman1, and Rahim R. Rizi2
1Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania, United States, 2Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States, 3Otolaryngology–Head & Neck Surgery, Johns Hopkins University, Baltimore, Maryland, United States

Positive end expiratory pressure (PEEP) protects surfactant deficient lungs from lung injury during mechanical ventilation. The mechanisms of this effect have not been established at the alveolar level. We used hyperpolarized gas MRI to quantify the effects of PEEP on lung microstructure on the alveolar and distal airspace level in surfactant deficient lungs. We show that, in spite of the increase in inspiratory pressures, PEEP alleviates airspace overdistension caused by surfactant deficiency. This technique can provide unique pathophysiological insight in the mechanisms of ventilator-associated lung injury.

14:30 3039.   Detection of Pulmonary Ischemia using the Oxygen Sensitivity of Hyperpolarized Helium MRI in a Rodent Model of Pulmonary Embolism 
Ronn P Walvick1,2, Austin L Reno2, Mathew J Gounis2, and Mitchell S. Albert2
1Radiology, New York University Langone Medical Center, New York, NY, United States, 2Radiology, University of Massachusetts Medical School, Worcester, MA, United States

Synopsis: In this work, we present data on the application of the measurement of measuring the time course of the partial pressure of oxygen in the lungs using hyperpolarized helium to detect ischemia in a novel rodent model of pulmonary ischemia. We show that both the initial partial pressure of oxygen is higher, and oxygen uptake rate in the ischemic lung is lower, in the ischemic then in the contralateral lung of embolized animals, and in both lungs of control animals. This work may be useful for the non-invasive evaluation of experimental treatment options for pulmonary embolism. 

15:00 3040.   Free vs Forced : Gas Transport Differences in 3He MRI Dynamic Ventilation Measurements of Lungs Induced by Gas Mixture Application Regime. 
Maxim Terekhov1, Manuela Gueldner2, Klaus Gast3, Julien Rivoire1, Ursula Wolf3, Janet Friedrich1, Sergei Karpuk2, Zahir Salhi2, and Laura Maria Schreiber1
1Department of Diagnostic and Interventional Radiology. Section of Medical Physics, Johannes Gutenberg University Medical Center Mainz, Mainz, Germany, 2Institute of Physics, Johannes Gutenberg University Mainz, 3Department of Diagnostic and Interventional Radiology, Johannes Gutenberg University Medical Center Mainz, Mainz, Germany

Dynamic ventilation (DV) of lung measured with 3He MRI is an efficient tool to visualize the intrapulmonary gas inflow. In current work we performed comparison 3He application with two different form of gas bolus: short bolus delivered by Application Unit (AU) in Free-Breathing mode and Forced Inspiration from Tedlar bag (TB) via fine tube with high resistance and prolonged bolus shape. The discrepancy between application modes was considered in terms of first orders Linear Transfer Function. The results show that TB-application changes significantly the gas transport in parenchyma and higher order derivations of “input bolus function” should be accounted.