Electronic poster

Thursday 13:30-15:00 Computer 101

13:30 4722. DTI at Different B-Values in Kidneys in Children with Unilateral Pylonephritis

Claudia Testa¹, Laura Miglio², David Neil Manners¹, Caterina Tonon¹, Emil Malucelli¹, Bruno Barbiroli¹, Andrea Pasini², Giovanni Tani², Raffaele Lodi<sup>1

1</sup>MR Spectroscopy Unit, Department of Internal Medicine, Aging and Nephrology, University of Bologna, Bologna, Bo, Italy; ²Paediatric Radiology Unit, Department of Woman, Child and Adolescent Health, University of Bologna, Bologna, Italy

DTI was used to evaluate renal damage in patients with chronic pyelonephritis. In 12 children affected by unilateral pyelonephritis as assessed by renal scintigraphy (Tc99-DMSA), axial DT images were acquired at b-values of 0, 100, 300, 600, 800 s/mm2. The mean diffusivity (D) and fractional anisotropy (FA) maps were generated for each b-value. We found that FA discriminated values from cortex and medulla better than D in healthy kidneys. D and FA decreased in affected kidneys at each b-values, in particular in the cortex of kidney poles. Changes of D and FA correlated with the degree of functionality damage found by scintigraphy.

14:00 4723. Effect of Nutritional State on IVIM Parameters Measured with Multiple B Value Diffusion MRI

Clifford R. Weiss¹, Atilla Peter Kiraly², Ralph Strecker<sup>3

1</sup>Department of Radiology, The Johns Hopkins Univeristy School of Medicine, Baltimore, MD, United States; ²Imaging and Visualization, Siemens Corporate Research, Princeton, NJ, United States; ³MR Oncology, Siemens Healthcare, Erlangen, Germany

Existing liver diffusion MR studies have moderate variability in computed ADC values. Reasons from transient changes in portal venous flow to noise have been attributed to this variability. However, the massive increase in splanchnic/portal blood flow after eating does not seem to be taken into account. We present a study comparing diffusion data before and after fasting that shows a large increase in ADC values after eating. Although it is a small study, results suggest that patient feeding state should be factored into future studies.

14:30 4724. High Directional Coherence in Renal Cortex as Shown in Diffusion Tensor Imaging

Ming-Cherng Wu¹, Yu-Chun Lin^1,2, Chung-Huang Hsieh¹, YauYau Wai^1,3, JiunJie Wang<sup>1,3

1</sup>Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, LinKou, Tao Yuan, Taiwan, Taiwan; ²Department of Electrical Engineering, Chang Gung University; ³Department of Medical Imaging and Radiological Sciences, ChangGung University

Renal cortex is the part of renal columns that contain the renal corpuscles and the renal tubules. The direction of water diffusion is consistent, which was properly reflected in the map of InterVoxel Diffusion Coherence. Diffusion Tensor Imaging in kidney were acquired from a 3T scanner. InterVoxel Diffusion Coherence detected high uniformity of the eigenvector distribution in the renal cortex. In the other hand, low Fractional Anisotropy in the corresponding regions suggested diffusion isotropy within cortex.

MRS - Body Applications

Hall B Monday 14:00-16:00 Computer 102

14:00 4725. ¹H-MRS Links Adipose Tissue Fat Composition to Liver Fat Content in Men with Metabolic Syndrome

Jesper Lundbom¹, Antti Hakkarainen¹, Sanni Söderlund², Nina Lundbom¹, Marja-Riitta Taskinen<sup>2

1</sup>HUS Medical Imaging Centre, University of Helsinki, Helsinki, Finland; ²Department of Medicine, University of Helsinki

We used 1H-MRS to study adipose tissue fat composition and liver fat content in men with the metabolic syndrome. Adipose tissue methylene/methyl, an index of saturated fats, correlated negatively with liver fat content.

14:30 4726. In-Vivo Determination of the Full¹H MR Spectrum of Liver Fat

Gavin Hamilton¹, Michael S. Middleton¹, Takeshi Yokoo¹, Mark Bydder¹, Irene W. Mwangi¹, Michael E. Schroeder¹, Claude B. Sirlin<sup>1

1</sup>Department of Radiology, University of California, San Diego, San Diego, CA, United States

Accurate proton (¹H) MRS fat quantification of liver fat requires determination of signal from fat peaks that are near or under the water peak. A theoretical triglyceride model was developed to characterize the liver fat spectrum, using number of -CH=CH- and -CH=CH-CH₂-CH=CH- bonds, and average fatty acid chain length. In vivo, the relative areas of the different fat peaks are strongly correlated suggesting the fat profile is uniform regardless of the level of fat deposition in the liver. The model gives that 8.6% of the total liver fat underlies the water peak.

15:00 4727. Comparison of Liver Steatosis Quantification by MRS at 4.7 T and Histology on Ob/ob and Db/db Mice

Fanny Noury^1,2, Alain Fautrel^3,4, Eric Hitti^1,2, Pascale Bellaud³, Hervé Saint-Jalmes^1,2, Bernard Fromenty⁴, Pierre-Antoine Eliat<sup>2

1</sup>LTSI - INSERM U642 - Université Rennes 1, Rennes, France; ²PRISM - IFR 140 BiogenOuest - Université Rennes 1, Rennes, France; ³Plate-forme d’Histopathologie - IFR 140 BiogenOuest - Université Rennes 1, Rennes, France; ⁴FMC - INSERM U991 - IFR 140 - Université Rennes 1, Rennes, France

Murine models of obesity such as ob/ob (leptin deficient) and db/db (leptin receptor deficient) mice are extensively used in different scientific fields including pharmacology and toxicology. Besides increased body fatness, hyperlipidemia and insulin resistance these mice develop moderate (db/db) or massive (ob/ob) steatosis. In some studies a longitudinal follow-up of steatosis may be warranted, to assess the beneficial (or deleterious) effects of chronic drug administration. In this preliminary study, db/db and ob/ob mice were used to determine whether magnetic resonance spectroscopy could be a reliable non-invasive method to evaluate fatty liver, using statistical comparison with histological results.

15:30 4728. Validation of ¹H Magnetic Resonance Spectroscopy (¹H-MRS) for Quantification of Hepatic Triglyceride Content

Estee Fleischman¹, Lauren Dutcher¹, David Thomasson², Adeline Louie², Haresh Mani³, David Kleiner³, Caryn Morse¹, Colleen Hadigan<sup>1

1</sup>National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States; ²Diagnostic Radiology Department, National Institutes of Health, Bethesda, MD, United States; ³National Cancer Institute, National Institutes of Health, Bethesda, MD, United States

There is growing interest in the application of 1H-MRS as a non-invasive approach to quantify hepatic triglyceride. This study was designed to establish the ability of 1H-MRS to accurately assess hepatic fat compared to histological scoring. Fifty subjects completed 1H-MRS of the liver within 30 days of diagnostic biopsy. The mean hepatic triglyceride content by 1H-MRS for each histologic grade was 9%, 23%, 40% and 56%, respectively. The correlation between the two methods was r=0.88, p<0.0001. With the phantom data we achieved an r=0.98 (p=0.02) over a range of fat-water fractions of 10 to 20 % using the standardized formula.

Tuesday 13:30-15:30 Computer 102

13:30 4729. A Simple Approach for Improving Lipid SNR for Hepatic Fat Measurement with 1H MRS

Giulio Gambarota¹, Mark Tanner¹, Johanna Berg², Robert V. Mulkern³, Rex D. Newbould<sup>1

1</sup>GlaxoSmithKline, London, United Kingdom; ²Radiology, University Hospital of Malmö, Sweden; ³Radiology, Children's Hospital Boston, Boston, MA, United States

Magnetic resonance spectroscopy (MRS) is becoming the method of choice for non-invasive assessment of lipids in liver. To avoid artifacts due to liver motion, MRS is often performed with a breath-hold approach. Given the limited amount of time available to perform the acquisition, it is of interest to maximize the signal-to-noise ratio (SNR) of the lipid resonances. Here, we show that it is possible to substantially improve the SNR of the in liver, by choosing an appropriate TR. The current approach has the advantage of experimental simplicity and can be applied to all basic sequences routinely used in clinical settings.

14:00 4730. Proton MRS of Changes of Lipid Unsaturation During Liver Regeneration

Kannie W. Y. Chan^1,2, April M. Chow^1,2, Shu Juan Fan^1,2, Ed X. Wu<sup>1,2

1</sup>Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; ²Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China

Post-operative diagnosis is important in partial hepatectomy (PHx) to determine the best time for interventions or therapeutic measures. We studied changes in unsaturated lipids verse saturated lipids as a mean to follow liver regeneration. The amount of unsaturated lipid at different time points showed a related trend with liver regeneration. A high level was found at 24h post-PHx, and was correlated with the maximum liver regeneration, and the saturated lipid stayed at a high level during the first day of regeneration. Thus, this pilot study shows that 1H-MRS could provide us with more information on the degree of regeneration.

14:30 4731. The Effect of Meal and Exercise on the in Vivo 31P-NMR Liver Spectrum: Initial Findings

Antti Hakkarainen¹, Jesper Lundbom^1,2, Esa K.J. Tuominen¹, Marja-Riitta Taskinen, Kirsi Hannele Pietiläinen³, Nina Lundbom<sup>1

1</sup>Helsinki Medical Imaging Centre, University of Helsinki, Helsinki, Finland; ²Department of Medicine, Division of Cardiology, University of Helsinki, Helsinki, Finland; ³Obesity Research Unit, Department of Psychiatry, Helsinki University Central Hospital, Helsinki, Finland

We studied the effects of a normal high-fat meal and subsequent exercise on the 31P MR spectrum of healthy volunteers using a proton-decoupled 31P MR spectroscopy at 3 T. We found a trend of rising ATP resonance at postprandial state suggesting that the physiological state may have an impact and should be standardized in phosphorus studies.

15:00 4732. Reproducibility Evaluation of Spatially Resolved Liver ³¹P Metabolism Using a Dual Tuned 8-Channel ³¹P/¹H Coil

Anshuman Panda^1,2, Scott Ray Jones^1,2, Ulrike Dydak<sup>1,2

1</sup>School of Health Sciences, Purdue University, West Lafayette, IN, United States; ²Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, United States

Regional changes in the ³¹P metabolite concentration of the whole liver can be acquired using a multi-channel phased-array ³¹P coil. However, changes in coil placement, separation between anterior and posterior coil, and spectroscopic imaging setup can significantly affect the reproducibility of the data. Methods to maximize data reproducibility including reproducible coil placement and spectroscopic planning, correction of coil sensitivities, and evaluation of the data variability from one scan to another for a whole liver ³¹P 2D MRSI experiment is presented for a dual tuned 8-channel ³¹P/¹H coil.

Wednesday 13:30-15:30 Computer 102

13:30 4733. In Vivo Proton MRS of Liver in an Experimental Liver Fibrosis Model

Jerry S. Cheung^1,2, Shu Juan Fan^1,2, Darwin Shan Gao^1,2, Kannie W.Y. Chan^1,2, April M. Chow^1,2, Kwan Man³, Ed X. Wu<sup>1,2

1</sup>Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; ²Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; ³Department of Surgery, The University of Hong Kong, Pokfulam, Hong Kong SAR, China

Carbon tetrachloride (CCl₄) intoxication is a well-characterized, reproducible and the most commonly used experimental model of liver fibrosis. Proton magnetic resonance spectroscopy (¹H MRS) can provide insights into in vivo liver metabolism noninvasively, yet detailed in vivo MRS study of CCl₄-induced liver fibrosis model has been limited. The aim of this study was to characterize early metabolic changes in CCl₄-induced liver fibrosis in rodents by means of single-voxel ¹H MRS. Our experimental results demonstrated that ¹H MRS at high field may be valuable in characterizing metabolic changes in liver, in particular those related to lipid and glutamine metabolism, after CCl₄ insult.

14:00 4734. Can Localised 19F MRS Pharmacokinetics of 5FU in Colorectal Metastases Predict Clinical Response?

Dominick John McIntyre¹, Franklyn Arron Howe², Christophe Ladroue², Fiona Lofts², Marion Stubbs¹, John Richard Griffiths<sup>1

1</sup>CRUK Cambridge Research Institute, Li Ka Shing Centre, Cambridge, United Kingdom; ²St George's, University of London, United Kingdom

We have applied 19F MRS to measure the pharmacokinetics of 5FU metabolism in the livers of 32 patients with colorectal cancer. 15 of the subjects had liver metastases. 5FU half-lives ranged from 4 to 15 minutes and were not significantly different between patients with and without liver metastases. In the group with metastases, high levels of toxic fluoronucleotides, primarily produced in tumour cells, were associated with poorer survival. This may be due to higher metastatic load giving higher concentrations of fluoronucleotides and poorer survival.

14:30 4735. Proton Magnetic Resonance Spectroscopy (¹H-MRS) of Adrenal Gland Masses Using a Multiple Array Coil (32 Channels) at 1.5T

Aude Fregeville¹, Stephane Silvera¹, Lionel Groussin², Olivier Vignaux¹, Victoria Cavero Machado³, Nashiely Pineda Alonso³, Paul Legmann<sup>1

1</sup>Department of Radiology, University René Descartes Paris V, Hôpital Cochin, Paris, France; ²Service des Maladies Endocriniennes et Métaboliques, University René Descartes Paris V, Hôpital Cochin, Paris, France; ³Siemens Healthcare, Paris, France

A size up to 3 cm lesion in the adrenal glands leads the patient to surgery. MRS is a promising tool for the classification of adrenal masses. We evaluated the advantages of multiple channel phased array (32-channel) coil in the respiratory-triggered proton single-voxel MR spectroscopy technique at 1.5 T for the diagnosis of adrenal masses and the differentiation between them. The gain in signal of the 32 channel coil gave an excellent spectral quality even in a free breathing acquisition at 1.5 Tesla. It is possible in deed to differentiate the types of masses by their spectral characteristics and ratios.

15:00 4736. Can Regurgitation of Pancreatic Juice Into the Biliary Tract Be Detected by ¹H MR Spectroscopy?

Omkar B. Ijare¹, Tedros Bezabeh¹, Nils Albiin², Annika Bergquist², Urban Arnelo², Mathias Lohr², Espen Melum³, Ian C.P. Smith<sup>1

1</sup>National Research Council Institute for Biodiagnostics, Winnipeg, Manitoba, Canada; ²Karolinska University Hospital, Karolinska Institutet, Huddinge, Stockholm, Sweden; ³Deparment of Medicine, Oslo University Hospital, Oslo, Norway

Regurgitation of pancreatic juice into the biliary tract and the subsequent mixing with bile is frequently observed in patients with pancreaticobiliary maljunction (PBM), which is a potential risk factor for the carcinogenesis of bile duct and gallbladder. The mixing of bile with pancreatic juice is generally diagnosed by measuring the amylase activity in bile. We propose that pancreaticobiliary reflux can be detected by ¹H MR spectroscopy as an alternative to the measurement of amylase activity. Moreover, it may be possible to detect non-invasively the regurgitation of pancreatic fluids into the gallbladder using in vivo spectroscopy.

Renal & Prostate

Hall B Thursday 13:30-15:30 Computer 102

13:30 4737. MR Voiding Cystourethrography (MRVC) for Vesicoureteric Reflux in Unsedated Infants

Owen John Arthurs¹, Ilse Joubert¹, Martin John Graves¹, Pat Set¹, David John Lomas<sup>1

1</sup>Department of Radiology, University of Cambridge and Addenbrooke's Hospital, Cambridge, Cambridgeshire, United Kingdom

Vesico-ureteric reflux is a congenital disorder of the paediatric renal tract, for which the current gold standard is the Micturating Cystourethrogram (MCUG). This study evaluated the feasibility of MR voiding cystourethrography using dilute intravesical gadolinium in unsedated infants. Real time interactive switching between gradient echo (SPGR) and SSFSE based pulse sequences allowed 6 children with urinary tract abnormalities to undergo both MCUG and MRI. There was 83% concordance between MCUG and MRVC regarding vesicoureteric reflux, and complete agreement regarding the urethra and bladder. Fluoroscopic MR assessment of the complete paediatric renal tract is possible in unsedated infants.

14:00 4738. Carr-Purcell-Meibom-Gill T2 Mapping of Prostate at 3 T.

Giulio Gambarota¹, R L. Janiczek¹, Robert V. Mulkern², Rex D. Newbould¹, Brandon Whitcher<sup>1

1</sup>GlaxoSmithKline Clinical Imaging Center, London, United Kingdom; ²Radiology, Children's Hospital Boston, Boston, United States

In clinical MR examinations of the prostate, a multiparametric approach (T1- and T2-weighted images, quantitative measurement of the apparent diffusion coefficient (ADC) of water, dynamic contrast-enhanced MRI) is becoming standard procedure. The Carr-Purcell-Meiboom-Gill (CPMG) approach has recently been proposed for T2 mapping of the prostate at 1.5 T. No such studies have been performed at 3 T. Translating the CPMG sequence to 3 T is not straightforward and involves compromises in clinical implementation. Here we have shown high quality measurements of T2 may be obtained over the entire prostate by careful design of the clinical acquisition.

14:30 4739. Ultra Short Gradient Echo Imaging of the Prostate at 7T

Gregory John Metzger¹, Steen Moeller¹, Patrick J. Bolan¹, Eddie J. Auerbach¹, Jang-Yeon Park¹, Michael Garwood<sup>1

1</sup>Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States

The purpose of this study was to investigate the potential of an ultra-short TE 3D radial sequence, for imaging the prostate at 7T. This technique is desirable for DCE-MRI because it would greatly reduce both the large T2* effect of paramagnetic contrast agents at high field, and the inflow artifacts that can bias the measurement of the arterial input function. Furthermore the sequence gives spatially isotropic resolution and, when combined with sparse temporal sampling methods, can provide very high temporal resolution. This work demonstrates the feasibility and imaging quality of this technique and discusses its strengths and weaknesses.

15:00 4740. Histopathological Composition of Prostate Tissues and Their Impact on DCE MRI Measures

Susan M. Noworolski^1,2, Kyle Kuchinsky³, Michelle Nystrom¹, John Kurhanewicz^1,2, Daniel B. Vigneron^1,2, Peter R. Carroll⁴, Kirsten Greene⁴, Jeffry Simko<sup>3

1</sup>Radiology and Biomedical Imaging, University of California, San Francisco, CA, United States; ²The Graduate Group in Bioengineering, University of California, San Francisco and Berkeley, CA, United States; ³Pathology, University of California, San Francisco, CA, United States; ⁴Urology, University of California, San Francisco, CA, United States

Validation of MR measures of the prostate are challenging due to heterogeneity. Tissue compositions by histopathology and their impact on DCE MRI measures were evaluated and compared in high and moderate grade prostate cancers. Fourteen men had DCE MRI before prostatectomy. High Gleason Grade (≥4+4) lesions had higher %cancer than Gleason 3+3 lesions (87% vs. 58%, p<0.00001). Normalizing DCE MRI measures to %cancer led to higher measures versus healthy peripheral tissues and greater separations between 3+3 and 4+4 cancers. Heterogeneity of tissues and %cancer may impact DCE MRI measures, with potentially different effects in Gleason Grade 3+3 versus 4+4 cancers.

MR Breast Cancer

Hall B Monday 14:00-16:00 Computer 103

14:00 4741. Shutter-Speed Model Dynamic Contrast-Enhanced MRI to Reduce Unnecessary Surgeries of Atypical Breast Lesions: A Preliminary Study

Luminita Alina Tudorica¹, Stephanie Hemmingson¹, Karen Oh¹, Arpana Naik¹, Sunitha Thakur², Elizabeth A. Morris², Mark Kettler¹, Ian J. Tagge¹, Jason A. Koutcher², Charles S. Springer¹, Wei Huang<sup>1

1</sup>Oregon Health & Science University, Portland, OR, United States; ²Memorial Sloan Kettering Cancer Center, New York, NY, United States

Three of 28 core needle biopsy-proven high-risk atypical breast lesions were upgraded to malignancies following surgical excisions as standard care. Correlations with pre-biopsy quantitative DCE-MRI results show that the Shutter-Speed Model (SSM) analyses of DCE-MRI data discriminate the atypical lesions between those completely benign and those containing malignancies with high accuracy. SSM DCE-MRI can potentially be used to reduce unnecessary surgeries of atypical lesions.

14:30 4742. Characterizing Suspicious Lesions with MR Guided Diffuse Optical Breast Imaging

Colin Morehouse Carpenter^1,2, Shudong Jiang², Steven P. Poplack³, Roberta M. diFlorio-Alexander³, Brian William Pogue², Keith David Paulsen<sup>2

1</sup>Radiation Oncology, Stanford University School of Medicine, Stanford, CA, United States; ²Thayer School of Engineering at Dartmouth, Hanover, NH, United States; ³Radiology, Dartmouth Hitchcock Medical Center, Lebanon, NH, United States

Breast MR has high sensitivity, yet suffers from comparatively low specificity. Optical imaging may aid MR mammography by providing spatial maps of disease-specific tissue properties such as total hemoglobin, oxygen saturation, water content, and tissue microstructure scatter, which have been shown in several studies to offer high specificity to malignant cancer. A multimodality MR-guided optical breast imaging instrument (MRg-OBI) has been developed and validated through numerous phantom and healthy volunteer studies. This study examined the ability of MRg-OBI in characterizing malignant from benign lesions in five patients. The results show that total hemoglobin is a good indicator of malignancy, with tumor to background contrast varying greatly from 1.25 up to 8.0, compared to less than 1 for the benign/fully responded lesions.

15:00 4743. Associations Between MR Derived Vascular, Shape and Texture Parameters with Histological Descriptors

Martin D. Pickles¹, Peter Gibbs¹, Martin Lowry¹, Lindsay W. Turnbull<sup>1

1</sup>Centre for MR Investigations, University of Hull, Hull, East Yorkshire, United Kingdom

Features such as shape (round, irregular), enhancement (homogeneous, heterogeneous), and kinetic curve assessment (persistent, plateau and washout) have been used to aid in the classification of breast lesions. These features may also help to highlight patients who subsequently have a reduced overall and disease free survival intervals. The aim of this work was to determine if there were any associations between pre-treatment MR derived quantitative descriptors (shape, enhancement and kinetic curve assessment) and traditional prognostic indicators. This work has demonstrated that when comparing traditional prognostic indicators (nodal ± hormonal status) significant differences in shape, texture and vascular kinetics are apparent.

15:30 4744. Evaluation of Sentinel Node with High Resolution Magic Angle Proton Magnetic Resonance Spectroscopy in Breast Cancer Patients: A Pilot Study

Surender Kumar¹, Raja Roy², Sandeep Kumar, Madhumati Goel, Ankita Rathore

¹General Surgery, King George's Medical University, Lucknow, Uttar Pradesh, India; ²CBMR, Centre of Biomedical Magnetic Resonance, Lucknow, Uttar Pradesh, India

The extent of axillary lymph node involvement in patients with cancer breast is an important prognostic marker. Prophylactic axillary dissection is associated with significant morbidity in clinically negative axilla. The intra-operative sentinel node biopsy (SNB) provides a basis for omitting the routine axillary dissection. However, it has limited sensitivity and requires complicated training and infrastructure. We report the use of high resolution magic angle proton magnetic resonance spectroscopy (HRMAS) in assessing the axillary nodal status with increased sensitivity.