ISMRM 21st Annual Meeting & Exhibition 20-26 April 2013 Salt Lake City, Utah, USA

Translational Scientific Session: Fat-Water Imaging - Translational Applications
Wednesday 24 April 2013
Room 155 EF  10:00 - 12:00 Moderators: Catherine D. G. Hines, Dimitrios Karampinos

10:00 0399.   
Free-Breathing Whole-Heart 3D Water-Fat Imaging: Clinical Experience
Valentina Taviani1, Diego Hernando2, Christopher J. Francois2, Scott K. Nagle1, Mark L. Schiebler1, Thomas M. Grist2,3, Karl K. Vigen1, Ann Shimakawa4, and Scott B. Reeder1,3
1Radiology, University of Wisconsin, Madison, WI, United States, 2Radiology, University of Wisconsin-Madison, Madison, WI, United States, 3Medical Physics, University of Wisconsin, Madison, WI, United States, 4Global MR Applied Science Laboratory, GE Healthcare, Menlo Park, CA, United States

Whole-heart 3D water-fat imaging during free-breathing can provide high-resolution fat-suppressed morphological images in patients incapable of holding their breath. In this work we evaluated a 3D chemical-shift-encoded pulse sequence with ECG gating and navigators in 15 patients referred for a wide variety of clinically-indicated cardiac MRI exams. Images were graded by two experienced radiologists on a 4-point scale for overall image quality and level of residual artifacts. Diagnostic images of good/excellent quality were obtained in all patients.

10:12 0400.   CAIPIRINHA-DIXON-TWIST (CDT) – Volume-Interpolated Breathhold Exam (VIBE) – a New Technique for Fast Time-Resolved Dynamic Three-Dimensional Imaging of the Abdomen with High Spatial Resolution -permission withheld
Henrik J. Michaely1, Katrin Koziel2, Philipp Riffel2, Johannes Budjan1, Stefan O. Schoenberg2, and Ulrike I. Attenberger2
1IKRN, UMM, Mannheim, BW, Germany, 2UMM, Mannheim, BW, Germany

A new dynamic sequence is presented that combines CAIPIRINHA acceleration, Dixon fat-saturation and TWIST view sharing with a VIBE sequence. Dynamic imaging of the abdomen has been evaluated with this technique at 3T with a spatial resolution of 1.2x1.2x3mm and a temporal resolution of 2.9s/3D data set.

10:24 0401.   Fat and Iron Quantification Using a Multi-Step Adaptive Fitting Approach with Multi-Echo GRE Imaging
Xiaodong Zhong1, Marcel D. Nickel2, Stephan A.R. Kannengiesser2, Brian M. Dale3, Berthold Kiefer2, and Mustafa Bashir4
1MR R&D Collaborations, Siemens Healthcare, Atlanta, GA, United States, 2MR Applications Development, Siemens AG, Healthcare Sector, Erlangen, Germany, 3MR R&D Collaborations, Siemens Healthcare, Cary, NC, United States, 4Division of Abdominal Imaging, Duke University Medical Center, Durham, NC, United States

In this work, a multi-step adaptive fitting approach was developed for fat and iron quantification using multi-echo 3D GRE data, which accounts for various factors such as T2* decay, T1 bias, multi-peak fat modeling, and noise bias. Numeric phantoms were created and used to validate the results measured by this approach with the ground truth, and showed that this approach is relatively insensitive to different field strengths, field inhomogeneity, monopolar/bipolar readout, and TE selections. An in vivo patient study showed consistency between the FP results measured with the proposed approach and a spectroscopy-based method.

10:36 0402.   Proton Density Fat Fraction Is a Highly Accurate Biomarker of Hepatic Steatosis in Adolescent Girls and Young Women
Jennifer Leigh Rehm1, Peter Wolfgram1, Ellen Lacon Connor1, Wei Zha2, David Allen1, Diego Hernando3, and Scott B. Reeder4
1Pediatrics, University of Wisconsin, Madison, WI, United States, 2Medical Physics, University of Wisconsin, Madison, WI, United States, 3Radiology, University of Wisconsin-Madison, Madison, WI, United States, 4Radiology, University of Wisconsin, Madison, WI, United States

Hepatic steatosis (HS) is a serious and growing problem in pediatrics. HS screening, including ultrasound or aminotransferases, are insensitive to early disease. In a diverse group of 132 adolescents, we demonstrate that proton density fat-fraction (PDFF) measured with quantitative MRI is a clinically relevant, non-invasive method for early detection and quantitative staging of hepatic steatosis. PDFF correlates with metabolic risk but BMI and ALT were not predictive of HS in overweight subjects. PDFF measured with quantitative MRI is a promising method for early identification of HS, allowing intervention prior to development of irreversible hepatic injury and progression of metabolic disease.

10:48 0403.   Comparing Brown Adipose Tissue in Infants and Teenagers by Chemical-Shift Water-Fat MRI
Houchun Harry Hu1, Larry Yin2, Thomas G. Perkins3, Jonathan M. Chia3, Patricia Aggabao1, and Vicente Gilsanz1
1Radiology, Children's Hospital Los Angeles, Los Angeles, California, United States, 2General Pediatrics, Children's Hospital Los Angeles, Los Angeles, California, United States, 3Philips Healthcare, Cleveland, Ohio, United States

This work compares brown adipose tissue (BAT) fat-signal fractions (FFs) and T2* values in nine infants (1.5±1.8m) and eighteen teenagers (12.5±1.9y). The teenagers were further divided into two sub-groups based on body-mass-index (BMI). mDIXON water-fat MRI was used to quantify FFs and T2* values in supraclavicular BAT depots on a 3T system. Infants had lower FFs than teenagers (36.0±8.2% vs. 68.7±12.2%, p<0.001), but T2* values were similar (18.7±2.6 vs. 17.2±3.8ms, p=0.29). Overweight teenagers had higher FFs (76.5±8.2% vs. 60.9±10.6%, p=0.003) and T2* values (19.0±4.2 vs. 15.3±2.1ms, p=0.031) than leaner subjects. FF and T2* values correlated with BMI (p<0.01) in teenagers.

11:00 0404.   Detection of Brown Fat Mass and Activity by Hyperpolarized Xenon MR
Rosa Tamara Branca1,2, Christian White1, and Le Zhang3
1Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States, 2UNC at Chapel Hill, Biomedical Research Imaging Center, Chapel Hill, North Carolina, United States, 3Material Science, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States

The detection of brown fat by conventional imaging methods (MRI, CT, 18FDG-PET) presents several challenges. This is because BAT fat-fraction can range from 40- 85%, while its metabolic activity relies mainly on fatty acid combustion. Here we demonstrate detection of BAT by in vivo HP-Xenon MR experiments and compare this methodology to 18FDG-PET and proton MRI. We show the possibility to directly map brown fat depot in the body, determine its fat fraction, measure the increase in BAT temperature and fatty acid consumption in real time by HP Xenon gas MR.

11:12 0405.   Simultaneous Fat, Water and T2* Mapping for Quantitative Characterization of Bone Marrow Pathology
Pippa Storey1, Stephen Honig2, David R. Stoffel1, and Sandra L. Moore1
1Radiology Department, New York University School of Medicine, New York, NY, United States, 2Division of Rheumatology, New York University School of Medicine, New York, NY, United States

Early malignant infiltration of bone marrow, characterized by small or diffuse lesions, is difficult to detect using routine sequences. We propose a multiple gradient echo technique to quantify trabecular loss (via R2*) and altered marrow fat content (via chemical shift). For validation purposes, the technique was tested in 6 patients with osteoporosis or osteopenia, using 8 healthy young men as controls. Both fat content and R2* differed significantly between patients and controls (p=0.04 and p=0.0003 respectively). Among patients, fat content and R2* exhibited significant correlations with bone mineral density evaluated by DXA (r=-0.89 with p=0.02, and r=0.88 with p=0.02 respectively).

11:24 0406.   Water-Fat MR Imaging for Assessing Changes in Bone Marrow Composition Due to Radiation and Chemotherapy in Gynecologic Cancer Patients
Patrick J. Bolan1, Luke Arentsen2, Thanasak Sueblinvong3, Yan Zhang4, Steen Moeller1, Jori Carter3, Levi S. Downs3, Rahel Ghebre3, Douglas Yee4,5, Jerry Froelich1, and Susanta K. Hui4,6
1Radiology, University of Minnesota, Minneapolis, MN, United States, 2Medical Physics, University of Minnesota, Minneapolis, Minnesota, United States, 3Obstetrics and Gynecology, University of Minnesota, Minneapolis, MN, United States, 4Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, United States, 5Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States, 6Therapeutic Radiology, University of Minnesota, Minneapolis, Minnesota, United States

This work demonstrates the feasibility of rapidly acquiring high-resolution 3D signal fat fraction (sFF) maps from mid-femur to the L3 lumbar vertebra, and that the sFF can detect and characterize marrow composition changes induced by chemotherapy and radiation therapy. The marrow fat fraction is potentially an imaging biomarker of bone marrow health and may be useful in planning and monitoring treatment of cancer patients.

11:36 0407.   Combination of a Fat Volume Fraction Quantification Method with a Dedicated Automatic Segmentation Algorithm for Simultaneous Measurement of Infiltrated Fatty Tissue Fraction and Muscle Relaxation Times.
Benjamin Leporq1, Arnaud Le Troter2, Yann Le Fur2, Emmanuelle Salort-Campana3, Patrick J. Cozzone2, Olivier Beuf1, and David Bendahan2
1CREATIS; CNRS UMR 5220; INSERM U1044; INSA-Lyon; UCBL, Université de Lyon, Villeurbanne, Rhone-Alpes, France, 2CRMBM; CNRS UMR 6612, Aix-Marseille Université, Marseille, PACA, France,3Reference Center for Neuromuscular Disorders, Timone Hospital, Assistance Publique Hopitaux de Marseille, Marseille, PACA, France

Due to its sensitivity to key processes in the diseased muscle such oedema, inflammation and fatty infiltration, MRI is emerging as a suitable quantitative method which could provide reliable surrogate markers of disease severity and progression. This work investigates the feasibility of a method to distinguish IMAT and SCAT, (ii) to measure muscle relaxation times (T1 andT2*) and to quantify the infiltrated fatty tissue fraction (IFTF) simultaneously. Our approach includes a magnitude-based fat volume fraction quantification method based on multiple-echo multiple angle acquisition with a dedicated automatic segmentation algorithm.

11:48 0408.   Combined T2 and IDEAL MRI Permit Identification of Nerve Injury Prior to Distal Muscle Inflammation and Atrophy, and Nerve Repair Prior to Muscle Regrowth -permission withheld
Saurav Chandra1, Nicole Londraville2, Samuel Cadena2, and Erica C. Henning1
1Global Imaging Group, Novartis Institutes for Biomedical Research (NIBR), Cambridge, MA, United States, 2Musculoskeletal Disease Area, Novartis Institutes for Biomedical Research (NIBR), Cambridge, MA, United States

Neurodegeneration is largely a consequence of aging, injury, or disease (eg., amyotrophic lateral sclerosis). Severe neurodegeneration is associated with muscle atrophy, impaired functional capacity, and in some cases, death. In this study, combined T2 and IDEAL MRI permitted non-invasive identification of nerve injury prior to distal muscle inflammation and atrophy, and nerve repair prior to muscle regrowth. This is with high sensitivity and reliability, without contrast agent. These findings provide selection of key time points for target identification and profiling of nerve injury/repair and muscle atrophy/regrowth.