Traditional Poster Session - Musculoskeletal
  Cartilage & Fibrocartilage 1380-1401
  Bone 1402-1424
  Muscle 1425-1447
  MSK Technical 1448-1461

Cartilage & Fibrocartilage
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Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

1380.   Quantification of longitudinal changes in cartilage following viscosupplementation therapy via T1lower case Greek rho MRI
Matthew Fenty1, Roshan Shah2, Yinan Kuang3, Jeff Stambough2, John Kelly4, Ravinder Reddy1, and Fotios Tjoumakaris5
1Center for Magnetic Resonance and Optical Imaging, University of Pennsylvania, Philadelphia, PA, United States, 2McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, United States, 3School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA, United States, 4Sports Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, United States, 5Sports Medicine, Rothman Institute, Egg Harbor Township, NJ, United States

Ten subjects who presented clinically with Kellgren-Lawrence grade 1 or 2 osteoarthritis were imaged using T1lower case Greek rho MRI following routine treatment using Hylan G-F 20 viscosupplementation. Quantitative assessments of cartilage health was analyzed prior to VS, 6 weeks post-, and 3 months post-surgery to examine effects of VS within the joint.

1381.   T1rho MRI of Acute Anterior Cruciate Ligament (ACL) Injured Patients at 3T
Ligong Wang1, Gregory Chang1, Jenny T. Bencardino1, James S. Babb1, Andrew Rokito2, Laith Jazrawi2, Orrin Sherman2, and Ravinder R. Regatte1
1Radiology, NYU Langone Medical Center, New York, New York, United States, 2Orthopaedic Surgery, NYU Langone Medical Center, New York, New York, United States

The goal of this study was to assess T1rho values of femorotibial cartilage in acute anterior cruciate ligament (ACL) injured patients compared to healthy controls and osteoarthritis (OA) patients at 3T. 53 subjects (16 healthy controls, 17 acute ACL injured patients, and 20 OA patients) were scanned. LFa in ACL injured patients had significantly higher T1rho values (P < 0.05) than whole femorotibial cartilage and all cartilage subregions except LFa in healthy controls. These findings imply that cartilage T1rho mapping may be sensitive in staging femorotibial cartilage disorder among acute ACL injured patients, healthy controls, and OA patients.

1382.   Quantitative Magnetization Transfer Analysis of In-Vivo Human Patellar Cartilage at 3.0T
Nade Sritanyaratana1, Alexey Samsonov2, Habib Abdulmohsen Al Saleh3, Kevin M Johnson3, Walter F Block4, and Richard Kijowski2
1Biomedical Engineering, UW-Madison, Madison, Wisconsin, United States, 2Radiology, UW-Madison, Madison, WI, United States, 3Medical Physics, UW-Madison, Madison, WI, United States, 4Biomedical Engineering, UW-Madison, Madison, WI, United States

Quantitative magnetization transfer (qMT) offers possible new biomarkers obtained through the magnetization transfer effect. Previous studies have observed qMT parameters of cadaveric or animal specimen cartilage, fixing T2b to calculate the fit. This study observed the bound pool fraction (f), exchange rate constant (k), and bound pool T2 (T2b) of patellar cartilage in human volunteers within 30 minutes. Significant differences (p=0.0001/0.002) were found in f/T2b between the deep and superficial layers of the cartilage. Additionally, it was found that the T2b in older active volunteers was significantly higher (p=0.01) than the T2b found in the younger sedentary volunteers.

1383.   Mapping of T2 and ADC in Articular Cartilage with B1 Corrected DESS
Bragi Sveinsson1,2, Ernesto Staroswiecki1,2, Kristin Granlund1,2, Garry E. Gold1, and Brian A. Hargreaves1
1Radiology, Stanford University, Stanford, California, United States, 2Electrical Engineering, Stanford University, Stanford, California, United States

Double Echo in Steady State is a 3D steady state method that has been demonstrated to provide accurate measurements of ADC in articular cartilage in short scan times with high SNR and low distortion. One approach estimates T1 and T2 as well as the ADC. Another approach eliminates dependency on T1 and T2 to estimate ADC more quickly. Both approaches suffer from sensitivity to B1 deviations when estimating ADC. We demonstrate a method to reduce errors caused B1 deviations. The method is tested in phantoms and in vivo with positive results.

1384.   Quantitative Assessment of Cartilage Using CubeQuant
Mai L.H. Nguyen1, Weitian Chen2, and Garry E. Gold3
1Stanford University, Stanford, CA, United States, 2Global MR Applied Science Laboratory, GE Healthcare, Menlo Park, CA, United States, 3Radiology, Bioengineering, and Orthopedics, Stanford University, Stanford, CA, United States

This work assesses the ability of CubeQuant, a new MR method based on 3D FSE, for 3D T1rho and T2 quantification of articular cartilage. A total of 9 patients were imaged with CubeQuant and a comparison of CubeQuant with MAPSS was performed on phantoms. There was good agreement between T2 relaxation time measurements with CubeQuant and MAPSS. In addition, correlation was seen between T1rho and T2 measurements in most regions of the cartilage. T1rho relaxation times were longer than T2 in all cartilage regions. CubeQuant can potentially provide traditional anatomic information in addition to biochemical data regarding cartilage.

Toshiyuki Shiomi1, Pavol Szomolanyi1,2, Vladimir Juras1,2, Stefan Zbyn1, Takashi Nishii3, and Siegfried Trattnig1
1MR Centre of Excellence, Department of Radiology, Medical University Vienna/Vienna General Hospital, Vienna, Austria, 2Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia, 3Department of Orthopaedics, Osaka University Medical School, Osaka, Japan

The purpose of this study was to characterize the time-dependence of cartilage stiffness under static loading using T2 mapping of the femoral cartilage of the knee joint in vivo in healthy volunteers. During the first loading period (10 minutes), the largest decrease of -8.2% of the T2 value was observed. T2 values exhibited a nonlinear dynamic change over time and reached stable values after 10 minutes of loading/unloading. Loading of the knee during MRI can provide biomechanical characteristics of the human knee cartilage. Statistically significant changes in cartilage T2 during the loading and unloading phases provide insight into cartilage properties.

1386.   Orientation and thickness dependent T2 mapping analysis of early knee cartilage degeneration using data from the Osteoarthritis Initiative.
Peter Huy Pham1, Scott Somers2, Nirmalya Ghosh3, and Hiroshi Yoshioka1
1Radiologic Sciences, University of California, Irvine, Orange, CA, United States, 2Radiology, Loma Linda University Medical Center, Loma Linda, CA, United States, 3Non-invasive Imaging Lab, Loma Linda Univeristy Medical Center, Loma Linda, CA, United States

We attempt to identify early knee cartilage damage and distinguish it from magic angle effect using a novel orientation and thickness dependent T2 mapping approach in Osteoarthritis Initiative patients. Custom software measured T2 relaxation time in cartilage divided by orientation relative to B0 and thickness. Approximately 85% of signal heterogeneity lesions and 100% of focal lesions <1cm were detected. Lesions at 55 degrees were distinguished from magic angle effect. Some lesions were only detectable on separate analysis of deep and superficial layers. Orientation and thickness dependent T2 mapping is sensitive for early cartilage degeneration and can separate it from magic angle effect.

1387.   A novel T2 mapping approach that can evaluate magic angle effect and T2 relaxation time in normal knee cartilage of patients from the Osteoarthritis Initiative
Scott M Somers1, Peter Pham2, Nirmalya Ghosh1, and Hiroshi Yoshioka2
1Radiology, Loma Linda University Medical Center, Loma Linda, California, United States, 2Radiology, University of California Irvine, Orange, California, United States

Because T2 relaxation time increases in cartilage before morphologic changes are visible, understanding the normal profile in cartilage is essential to identifying early disease. Using custom software, we measured T2 relaxation time in 5 degree segments for deep, superficial, and full thickness cartilage of the medial femoral condyle in 105 patients using a novel T2 mapping approach. The results of this study emphasize the importance of evaluating deep and superficial cartilage separately, as well as considering orientation of the cartilage to the main magnetic field when T2 mapping is used for diagnosis of cartilage disease.

1388.   Imaging of the osteochondral interface and deep cartilage using SWIFT
Mikko Johannes Nissi1, Jinjin Zhang1, Djaudat Idiyatullin1, Curtis Corum1, Cathy Carlson2, Ferenc Toth2, Miika Tapio Nieminen3,4, and Jutta Ellermann1
1CMRR - Dept. of Radiology, University of Minnesota, Minneapolis, MN, United States, 2Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, Minneapolis, MN, United States, 3Department of Medical Technology, University of Oulu, Oulu, Finland, 4Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland

The involvement of the osteochondral interface in osteoarthritis is known, but perhaps less appreciated than warranted. Recent developments in ultrashort/zero-echo time imaging methods have enabled the MRI investigation of calcified and subchondral structures. In uTE studies, the bright line at the cartilage-bone interface has been associated with calcified layer of cartilage and deep layers of cartilage. In the present study, SWIFT was utilized to further study the origin of this feature. The results confirmed the earlier findings but also pointed to a possible contribution of signal pileup due to susceptibility differences between cartilage and bone or calcified cartilage.

1389.   High Resolution UTE Imaging on Knee Patients at 3T
Yongxian Qian1, Ashley A. Williams2, Constance R. Chu2, Cynthia A. Britton1, and Fernando E. Boada1,3
1Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States, 2Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, United States,3Bioengineering, University of Pittsburgh

This work illustrates the potential of high resolution (0.14mm) ultrashort echo time (UTE) imaging for non-invasively visualizing micro cartilage defects and damages in human knee. Five patients with clinically-graded cartilage defects (arthroscopic grading) were scanned on a clinical MRI scanner at 3T, using a customer-developed fast 3D UTE pulse sequence, acquisition-weighted stack of spirals (AWSOS). The findings on HR-UTE images were verified by the clinical arthroscopic grading.

1390.   In vivo transport of Gd-DTPA2- after intravenous and intra-articular injection
Eveliina Lammentausta1, Simo Saarakkala2,3, Risto Ojala2, and Miika T Nieminen2,3
1Department of Clinical Imaging, Oulu University Hospital, Oulu, OYS, Finland, 2Oulu University Hospital, 3University of Oulu, Oulu, Finland

T1 relaxation time was measured 90 minutes after intravenous and intra-articular Gd-DTPA administration to investigate the transport routes of gadolinium into articular cartilage. Significan differences were observed in superficial and full thickness cartilage, but not in deep cartilage. The present results suggest that most of the Gd-DTPA transports into articular cartilage from the synovial fluid regardless of the injection method.

1391.   3D HR-MRI at 3T for dedicated visualization of in-vivo locoregional deformation pattern of the knee cartilage for cartilage contact areas in different work-related flexion postures
Annie Horng1, José Raya2, Monika Zscharn1, Ulrike Hoehne-Hueckstaedt3, Ulrich Glitsch3, Rolf Ellegast3, Kurt Georg Hering4, Maximilian F Reiser1, and Christian Glaser1
1Department of Clinical Radiology, University Hospitals LMU Munich Campus Grosshadern, Munich, Bavaria, Germany, 2Center of Biomedical Imaging, New York University Medical Hospital, New York, New York, United States, 3Fachbereich 4, Institut für Arbeitsschutz der Deutschen Gesetzlichen Unfallversicherung, St. Augustin, Germany,4Department of Radiology and Nuclear Medicine, Knappschaftskrankenhaus, Dortmund, Germany

Cartilage strain is considered a potential cause for degeneration and osteoarthritis. 3D-HR-MRI was utilized and proved able to evaluate the dimension and distribution of cartilage deformation in the knee joint after different standardized flexion exercises. The deformation pattern was similar for the excercises, possibly a consequence of mutual knee flexion over 90°. Specific patterns were visible for squatting and knee bends possibly due to higher flexion grade in the former and dynamic movement character in the latter. The data may support the understanding of individual knee kinematics and contribute to improvement and validation of biomechanical models for the knee.

1392.   Automated Bone Segmentation and Bone-Cartilage Interface Extraction from MR Images of the Hip
Ying Xia1,2, Jurgen Fripp2, Shekhar Chandra2, Olivier Salvado2, Raphael Schwarz3, Lars Lauer3, Craig Engstrom4, and Stuart Crozier1
1School of Information Technology and Electrical Engineering, University of Queensland, Brisbane, Australia, 2The Australia e-Health Research Centre, CSIRO ICT Centre, Brisbane, Australia, 3Siemens Healthcare, Erlangen, Germany, 4School of Human Movement Studies, University of Queensland, Brisbane, Australia

Osteoarthritis (OA) is a common disease of the hip joint characterized by changes in structure and degeneration of cartilage tissue. Magnetic Resonance (MR) imaging has been shown to be an ideal modality for OA assessment, providing direct and non-invasive visualization of joint structure. Morphological measurements (volume, thickness and surface area) of the cartilage tissue have been shown to be important in characterizing and monitoring OA progression, which allows the prediction of its subsequent changes and in-time therapeutic treatment before permanent damage has been developed. In this paper, we present validation of our fully automated scheme for the bone segmentation and qualitative bone-cartilage interface (BCI) extraction and initial cartilage segmentation from MR images of the hip joint.

1393.   Solid-state MAS NMR Measurements of Intact Articular Bovine Cartilage
R Mark Wellard1, Alf Pawlik2, Sabrina Barheine2, and Konstantin I Momot3
1QUT, Brisbane, Qld, Australia, 2QUT, 3QUT, Australia

The early changes associated with osteoarthritis of articular cartilage are not well understood. Our objective was to better understand the metabolite distribution in cartilage. We studied the changes in intact bovine patellar cartilage using solid-state 1H and 13C MAS NMR following incubation of the cartilage in D2O to remove free water. The influence of freezing and thawing on the eluted metabolites was determined using 13C NMR. Examination of the 1H MAS NMR spinning side-bands suggests the presence of multiple bound states of water. Metabolite elution following frozen storage of cartilage shows an increased loss of proteoglycans, relative to fresh tissue.

1394.   Sodium MR imaging of the goat knee at 1.5T using a TORO (transmit-only, receive-only) coil and a 3D UTE sequence
Gunthard Lykowsky1, Kathrin Hemberger1, Peter M. Jakob1,2, and Daniel Haddad1
1MRB Research Center, Würzburg, Germany, 2Department of Experimental Physics 5, University of Würzburg, Würzburg, Germany

Sodium is known to be a sensitive MR imaging biomarker for early diagnosis of knee articular cartilage osteoarthritis (OA). The goat animal model closely matches the human knee anatomy and can be used to mimic the progressive nature of OA and monitor the loss of proteoglycans. We have developed a TORO (transmit-only, receive only) coil setup which allows, in combination with a 3D UTE sequence, improved sodium imaging of the goat knee at 1.5T. High quality sodium images of the goat knee are shown.

1395.   Morphological assessment of non-human primate model of osteoarthritis: Comparison of HR-MRI with CT arthrography (CTA)
Anne-Laure Perrier1, Emmanuel Chereul2, Denis Grenier1, Fabrice Taborik3, Mariam Abdallah1, Thomas Chuzel2, Stéphane Martin2, Luc Magnier2, Jean-Christophe Goebel1, Xavier Pesesse4, Sandra Pietri5, Hugues Contamin3, and Olivier Beuf1
1Université de Lyon; CNRS UMR 5220; Inserm U1044, INSA-Lyon; Université Lyon 1, Villeurbanne, France, 2VOXCAN, Marcy l'Etoile, France, 3Cynbiose, Marcy l’Etoile, France,4Bone Therapeuthics, Grosselies, Belgium, 5Laboratoire de Rhumatologie, Hôpital Erasme, ULB, Bruxelles, Belgium
Small animal model of osteoarthritis (OA) models do not always mimic with adequacy human disease. Moreover, despite superior tissue contrast and sensitivity to cartilage tissue structure, spatial resolution is limited compared to CT scanner and an accurate determination of cartilage morphology is challenging due to the small size of rodent joints. In the contrary, OA that closely resembles to the human condition occurs naturally in primate. In this context, the aim of this work was (i) to develop a dedicated protocol for knee joint examination of cynomolgus primates at 1.5T and with µ-CT arthroscanner (µCTA); (ii) to compare morphological parameters assessed based on MRI and µCTA acquisitions on a group of 10 old primates with spontaneous OA.

1396.   Monitoring the Formation of Tissue-Engineered Cartilage in Scaffold-Free Pellet Culture Using Magnetic Resonance Imaging
Ziying Yin1, Thomas M. Schmid2, Lawrence Madsen2, Mrignayani Kotecha1, and Richard L. Magin1
1Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, United States, 2Department of Biochemistry, Rush University, Chicago, IL, United States

Noninvasive assessment of tissue-engineered cartilage is essential to optimize the production of neocartilage with appropriate biochemical properties for implantation; MRI is ideally suited to this. One approach to regenerating cartilage involves culturing chondrocytes in scaffold-free pellet culture. In this study, we used MRI to evaluate the scaffold-free chondrocyte pellets over a 4-week period, and observed the distinct changes in histograms of T2, T1, T1¦Ñ and apparent diffusion coefficient, which were correlated with the results of biochemical determination of proteoglycan and collagen from the pellets. The results suggest that MRI could be used to assess specific biochemical properties of engineered cartilage.

1397.   Identification of in vitro degenerated porcine meniscal tissue: MTR contrast prevents misinterpretation due to the magic angle effect
Christina Hopfgarten1, Stefan Kirsch1, Gregor Reisig2, Michael Kreinest2, and Lothar R. Schad1
1Computer Assisted Clinical Medicine, University Medical Centre Mannheim, Heidelberg University, Mannheim, Germany, 2Department for Experimental Orthopaedics and Trauma Surgery, University Medical Centre Mannheim, Heidelberg University, Mannheim, Germany

Interpretation of MR images of menisci is hampered by the magic angle (MA) effect. The MA effect manifests itself as a strong spatial inhomogeneity in the MR images caused by orientational dependence of the transverse relaxation time T2. Here we demonstrate experimentally that magnetization transfer ratio (MTR) maps show no visible sensitivity to the MA effect. Therefore, MTR maps have the potential to identify tissue degeneration while not being affected by the MA effect. This phenomenon could be useful in in vivo studies of pathological tissue degeneration of human menisci.

1398.   Rapid 3D quantitative DESS T2 and T2* Mapping in the Meniscus
Emily J McWalter1, Bragi Sveinsson1, Ernesto Staroswiecki1, Marcus T Alley1, Brian A Hargreaves1, and Garry E Gold1
1Radiology, Stanford University, Stanford, CA, United States

We demonstrated the feasibility of measuring T2 and T2* relaxation of the meniscus in vivo using 3D quantitative DESS (qDESS) in 5 healthy individuals. The results of this study are consistent with previous meniscal T2 and T2* measurements in healthy volunteers with mean values of 10.5 ± 1.6 ms and 7.2 ± 0.6 ms, respectively; however, we were able to acquire data of similar resolution in shorter scan times and create maps in three planes. 3D qDESS has the potential to be used for detecting early meniscal degeneration.

1399.   Aging effect on zonal and sex differences of human meniscus investigated by MR T2 measurements
Ping-Huei Tsai1,2, Shih-Wei Chiang3, Yue-Cune Chang4, Chao-Ying Wang3, Ming-Chung Chou5, Hsiao-Wen Chung6, and Guo-Shu Huang3
1Imaging Research Center, Taipei Medical University, Taipei, Taiwan, 2Department of Radiology, WanFang Hospital, Taipei, Taiwan, 3Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, 4Department of Mathematics, Tamkang University, Taipei, Taiwan, 5Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung, Taiwan, 6Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan

Human meniscus plays an important role on maintenance of the knee mechanical functions and is strongly associated with early detection of osteoarthritis (OA) which is frequently characterized with degeneration of cartilage and mostly related to aging. Zonal difference of the meniscus was demonstrated by previous report using quantitative T2 measurements. In addition, aging and gender may be other factors that could affect the diagnostic value of quantitative T2 measurements in the menisci. The purpose of this study is to investigate the relationship between regional T2 variations and aging effect in asymptomatic men and women.

Accurate Measurement of Cartilaginous Endplate of the Intervertebral Disc of In Vivo MRI Data
Sung M. Moon1,2, Jon H. Yoder2, Ed J. Vresilovic3, Dawn M. Elliott2, and Alexander C. Wright1
1Laboratory for Structural NMR Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, United States, 33Department of Orthopaedics and Rehabilatation, Penn State University, Hershey, PA, United States

Intervertebral disc degeneration is considered one of the key causes of back pain while very little is known about the MR characteristics of the CEP (cartilaginous end-plate) because it is very thin (~600µm) and difficult to image and recognize on routine MR exams. Visualizing CEP and/or measuring water content of the CEP are important for the evaluation of disc degeneration. However, measuring CEP thickness challenging in vivo due to voxel size. In this study, high-resolution ex vivo CEP images and low-res in vivo images were acquired and evaluated for different voxel sizes, and estimated error was reported using automated program.

1401.   Assessment of T1lower case Greek rho Mapping of Thoracolumbar Discs at 3T with and without RF Shimming
Trevor Andrews1,2, Richard Watts2, Scott Hipko2, Jay Gonyea2, and Christopher Filippi2,3
1Philips Healthcare, Cleveland, OH, United States, 2Radiology, University of Vermont College of Medicine, Burlington, VT, United States, 3Radiology, Fletcher Allen Health Care, Burlington, VT, United States

In this work the performance of 3D T1rho mapping of spine discs at 3T is investigated both with and without RF shimming.
Traditional Poster Session - Musculoskeletal

Click on to view the abstract pdf. Click on to view the poster (Not all posters are available for viewing.)
Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

Compressed Sensing 3D Ultrashort Echo Time (COMPUTE) Imaging
Cheng Li1, Jeremy Magland1, and Felix Wehrli1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States

Ultra-short echo time (UTE) imaging is a technique for directly imaging tissues with sub-millisecond T2 values. However, 2D UTE imaging is inherently time-inefficient because of half-pulse excitation and radial center-out sampling. In this work we describe 3D Compressed Sensing UTE (COMPUTE) imaging with a hybrid-radial encoding strategy to improve efficiency. Phantom and in vivo results demonstrate the feasibility of COMPUTE technique with an acceleration factor of 10. In work in progress, long-T2 suppression modules are being incorporated into COMPUTE, allowing spatial sparsity of the soft-tissue suppressed images to be exploited to achieve even higher acceleration factors.

1403.   Demonstrable BOLD Effect in Human Bone Marrow
David K.W. Yeung1, James F Griffith2, Heather T Ma3,4, and Alvin F.W. Li2
1Imaging and Interventional Radiology, Prince of Wales Hospital, Shatin, HKSAR, Hong Kong, 2Imaging and Interventional Radiology, The Chinese University of Hong Kong, Shatin, HKSAR, Hong Kong, 3Department of Electronic and Information Engineering, Harbin Institute of Technology, China, 4Imaging and Interventional Radiology, The Chinese University of Hong Kong, HKSAR, Hong Kong

What causes osteoporosis is still incompletely understood. One hypothesis that has recently attracted a lot of attention is the vascular origin of the disease. In this study we attempted to use BOLD imaging to study bone marrow perfusion. We showed that observable BOLD signal changes may be measured from the bone marrow of human volunteers.

1404.   Feasibility of the residual red marrow assessment in tibia epiphysis after age 25 using DTI: the initial investigation on healthy volunteers
Bailiang CHEN1,2, Tryphon Lambrou3, Gabriela HOSSU1,4, Pedro Teixeira5, Pierre-André VUISSOZ1,2, and Jacques FELBLINGER1,2
1IADI, INSERM U947, Nancy Université, Nancy, Lorraine, France, 2Pôle Imagerie, CHU de Nancy, Nancy, France, 3Institute of Nuclear Medicine, University College London, London, United Kingdom, 4CIC-IT 801, CHU de Nancy, Nancy, France, 5Service d’Imagerie Guilloz, CHU de Nancy, Nancy, France

Bone marrow is a dynamic organ with significant changes in its composition throughout life. Alterations in the conversion between red (hematopoietic) and yellow (adipose) marrow may be a sign for an alteration of the local microvascular environment caused by local or systemic diseases. The distribution pattern of red bone marrow, residual or reconverted, may assist the differentiation between normal and pathologic bone marrow. Such residual red marrow is sometimes difficult to be detected by conventional sequences. In this study, we presented an in-vivo diffusion based MR protocol to assess the red marrow in the tibia epiphysis.

1405.   Lipidic profile of bone marrow in peripheral skeleton sites assessed by 1H-MRSpectroscopy: looking for instrumental biomarkers of osteoporosis.
Giulia Di Pietro1,2, Vincenzo Vinicola3, Guglielmo Manenti4, Mauro Rebuzzi2, Gisela Hagberg5, Salvatore Masala4, Giovanni Simonetti4, Marco Bozzali5, and Silvia Capuani2,6
1IIT@Sapienza, Physics Department, Rome, Rome, Italy, 2“Sapienza” University of Rome, Physics Department, Rome, Rome, Italy, 3Rehabilitation Hospital IRCCS Santa Lucia Foundation, Rome, Italy, 4Department of Diagnostic Imaging and Interventional Radiology, University of “Tor Vergata”, Rome, Italy, 5Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy, 6CNR IPCF UOS Roma, Physics Department, Rome, Italy

Lipidic profile of bone marrow was investigated, using 1H-MRS at 3T, in the calcaneus and the femoral neck of postmenopausal healthy , osteopenic and osteoporotic women. Preliminary data obtained in femur, indicate that resonance L53 is a biomarker suitable for identifying healthy subjects, while resonance L09 is the best marker to identify osteoporotic subjects. Taken together, these measures might provide a sensitive and specific test for screening of populations at risk for osteoporosis. Additionally, in calcaneus, the simultaneous quantification of resonances L09,L43, L41 and L28+L23+L21 offers a chance to increase the diagnostic confidence of osteoporosis in low cost dedicated spectrometers.

1406.   Rapid Chemical Shift Imaging Method and Processing for Quantification of Bone Marrow Fat Fraction in the Vertebrae
Maite Aznarez-Sanado1, Cheng Li1, Jeremy F Magland1, Chamith S Rajapakse1, and Felix W Wehrli1
1Laboratory for Structural NMR Imaging, University of Pennsylvania, Philadelphia, Pennsylvania, United States

Proton MR spectroscopy is a valuable technique for the assessment of bone marrow. The main purpose of this study was to evaluate the performance of a fast, multi-echo chemical-shift imaging method for in vivo quantification of vertebral marrow fat fraction. Five healthy subjects underwent the imaging paradigm twice with complete repositioning of the subject each time. In vivo marrow fat fraction measurements obtained at each vertebral level (L1-L5) were highly reproducible. The results suggest that this technique may reliably detect variations in the marrow fat fraction on the order of 4% in 95% of the cases.

1407.   DTI and MRS assessment of cancellous bone quality in femoral neck of healthy, osteopenic and osteoporotic subjects at 3T
Silvia Capuani1, Guglielmo Manenti2, Roberto Sorge3, Parfait Assako2, Umberto Tarantino4, Salvatore Masala2, and Giovanni Simonetti2
1Physics Department, CNR IPCF Roma "Sapienza " University of Rome, Rome, Italy, Italy, 2Diagnostic and Interventional Radiology, Molecular Imaging and Radiotherapy, "Tor Vergata" University of Rome, Rome, Italy, 3Institute of Medical Informatics and Biometry, "Tor Vergata" University of Rome, Rome, Italy, 4Department of Orthopaedics and Traumatology, PTV Foundation, "Tor Vergata" University of Rome, Rome, Italy

We reported, for the first time, MD and FA results obtained from femoral neck of healthy (H), osteopenic (OPE) and osteoporotic (OPO) subjects, classified according to DXA criteria. Because MD and FA in cancellous bone depend on both the trabecular-bone rearrangement and the marrow fat-water ratio content (FF) a DTI protocol in combination with 1H-MRS was used. Our preliminary results, show that MD/FF and FA/FF differentiate among H, OPE and OPO subjects with a high sensitivity and specificity in identifying H subjects. DTI-1H-MRS assessment in femoral neck might represent a potential procedure to improve the diagnostic confidence of osteoporosis.

1408.   Feasibility of In Vivo MR Image-based Micro Finite-Element Analysis of the Proximal Femur
Maite Aznarez-Sanado1, Chamith S Rajapakse1, Ning Zhang1, Jeremy F Magland1, Michael J Wald1, Alex C Wright1, Yusuf A Bhagat1, Wenli Sun1, and Felix W Wehrli1
1Laboratory for Structural NMR Imaging, University of Pennsylvania, Philadelphia, Pennsylvania, United States

Assessment of bone strength in the proximal femur, a frequent site of traumatic fracture, is of significant clinical interest. Micro finite-element analysis (lower case Greek muFEA) is a valuable tool for estimating bone strength. To determine the viability of lower case Greek muFEA on the basis of in vivo lower case Greek muMR images obtained at the proximal femur, lower case Greek muFEA based on ex vivo high-resolution micro-computed tomography, simulated low resolution lower case Greek muMR and in vivo lower case Greek muMR images were performed. Strain maps derived from the analyses qualitatively showed similar loading characteristics. The results indicate the feasibility of lower case Greek muFEA based on in vivo lower case Greek muMR images of the proximal femur.

1409.   Performance Evaluation of a Non-linear Finite-Element Model for Assessing Yield Strength from in Vivo 3D MR Images of Trabecular Bone
Ning Zhang1, Jeremy F Magland1, Chamith S Rajapakse1, Yusuf A Bhagat1, and Felix W Wehrli1
1Laboratory for Structural NMR Imaging, University of Pennsylvania, Philadelphia, PA, United States

High-resolution image-based non-linear micro-finite element (µFE) modeling can directly predict bone failure behavior thereby assessing osteoporotic fracture risk. In this work, a new program for non-linear μFE modeling was developed to estimate trabecular bone (TB) yield parameters based on a computationally efficient algorithm for linear µFE analysis in conjunction with establishment of a TB failure criterion. A reproducibility study on in-vivo μMR images was conducted to assess its performance. The ability to distinguish means between four healthy young subjects suggests that the yield parameters derived from the non-linear program have reproducibility adequate to evaluate treatment effects in interventional studies.

1410.   Image-based Finite-Element Bone Mechanics Simulations: Does Stiffness Predict Yield Strength?
Ning Zhang1, Jeremy Magland1, Chamith Rajapakse1, Yusuf Bhagat1, and Felix Wehrli1
1Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States

High-resolution MR or CT image-based micro-finite element modeling has shown promise for estimating bone mechanical behavior, assessing osteoporotic fracture risk and evaluating the response to drug intervention. Limitations in computing power so far have restricted μFE models to the linear regime yielding only bone elastic parameters. In contrast, nonlinear μFE models are able to predict bone’s failure strength but are computationally far more demanding. In this work we apply newly developed µFE software to explore the relationship between trabecular bone yield stress predicted by nonlinear μFE and axial stiffness computed from linear μFE models and present initial results on the basis of μMR and μCT images.

1411.   Sensitivity of Detecting Trabecular Bone Loss using In-Vivo Micro-MRI-based Biomechanics
Wenli Sun1, Chamith Rajapakse1, and Felix W. Wehrli1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States

Although micro-MRI-based biomechanics has been used to study mechanical alterations in trabecular bone due to disease or treatment, sensitivity of this approach under typical patient imaging conditions has not been well established. We investigated weather finite-element analysis performed on the basis of simulated ¡°in vivo¡± micro-MR images of the distal tibia is capable of detecting a reduction in axial stiffness resulting from a small amount of trabecular bone erosion and perforation. The data suggest that mechanical implications caused by subtle changes in trabecular bone are detectable via finite-element modeling under in-vivo micro-MR imaging conditions now achievable in patients.

1412.   Longitudinal Characterization of Trabecular Bone Microstructure and Computational Biomechanics for Determining Treatment Effects in Postmenopausal Women
Yusuf A Bhagat1, Maite Aznarez-Sanato1, Jeremy F Magland1, Theresa M Scattergood2, Peter J Snyder2, and Felix W Wehrli1
1Laboratory for Structural NMR Imaging, University of Pennsylvania, Philadelphia, PA, United States, 2Division of Endocrinology, Diabetes and Metabolism, University of Pennsylvania, Philadelphia, PA, United States

Recent advances in high-resolution structural imaging of trabecular and cortical bone and the use of these data as input into micro-finite-element (µFE) models have shown potential for assessing the effect of treatment in patients with osteoporosis. Here, we report baseline and 1 year follow-up data in an ongoing investigation of women with low bone density (N=15) receiving either zoledronic acid or teriparatide, conducted at 3T and 7T. The baseline data show moderate associations with pQCT bone density while µFE-derived axial stiffness is strongly correlated with bone volume fraction at the same site. Finally, repeat data in select subjects indicate large anabolic effects.

The Suppression Ratio as a Surrogate Marker of In Vivo Cortical Bone Porosity
Cheng Li1, Yusuf A Bhagat1, and Felix W Wehrli1
1Laboratory for Structural NMR Imaging, University of Pennsylvania, Philadelphia, PA, United States

Ultra-short echo-time (UTE) MRI enables detection of cortical bone water. Quantification of pore water would permit an indirect estimation of porosity, currently unachievable in vivo. In this study, we examined the role of the suppression ratio (SR, unsuppressed/soft-tissue suppressed UTE signal) as a surrogate measure for porosity in 18 healthy women (27-81 years old) who underwent scanning of the mid-diaphyseal tibia at 3T with three soft-tissue suppression UTE-MRI schemes. SR was found to increase with age and was inversely correlated with bone mineral density. SR may provide an in vivo surrogate measure of porosity.

1414.   Magnetic Field Dependence of 31P Relaxation in Cortical Bone
Alan C Seifert1, Alexander C Wright1, Henry H Ong1, Thomas J Connick1, Stephen Pickup1, Suzanne L Wehrli2, and Felix W Wehrli1
1Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2NMR Core Facility, Children's Hospital of Philadelphia, Philadelphia, PA, United States

X-ray-based bone mineral density examinations measure apparent, rather than true, density. Solid-state 31P MRI has the potential to quantify true density, but due to uniquely unfavorable relaxation properties, SNR’s dependence on field strength is not certain. We therefore measured T1 and T2* of 31P in five lamb cortical bone samples by saturation-recovery and line width at five field strengths (3T-11.7T), and calculated predicted SNRs using the gradient-echo signal equation. With increasing B0, T1 increased from 26s to 97s, and T2* decreased from 189µs to 98µs. If k-space center is sampled <130µs after excitation, higher field strength should provide better SNR.

1415.   Bound and Pore Water-Discriminated MRI in Human Cortical Bone
R. Adam Horch1,2, Jeffry S Nyman3,4, Daniel F Gochberg2,5, Mary Kate Manhard1,2, and Mark D Does1,2
1Biomedical Engineering, Vanderbilt University, Nashville, TN, United States, 2Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 3VA Tennessee Valley Healthcare System, 4Department of Orthopaedics & Rehabilitation, Vanderbilt University, Nashville, TN, United States, 5Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States

Modern ultrashort echo-time (uTE) MRI is a clinically feasible method for imaging human cortical bone. The conventional uTE signal from cortical bone contains non-discriminated contributions from both bound and pore water. Previous work has linked bound or pore water-discriminated measures to bone mechanical properties, so it is necessary to isolate bound from pore water for diagnostic utility. This work explores two modifications to uTE MRI, which incorporate T2-selective adiabatic full passage (AFP) RF pulses to selectively image bound or pore water. These AFP methods are performed with clinically-relevant scan parameters and provide quantitative images of bound or pore water.

1416.   SAR around uni- and bi-lateral metal-on-metal hip implants at 1.5 and 3T
Annie Papadaki1, Jeff Hand2, John Powell3, Donald McRobbie4, and Alister Hart5
1Radiological Sciences Unit, Imperial College Healthcare NHS Trust, London, England, United Kingdom, 2Imaging Sciences, Imperial College, London, United Kingdom, 3Stroke and Dementia Research Centre, St Georges University of London, London, England, United Kingdom, 4Radiological Sciences Unit, Imperial College NHS Trust, London, England, United Kingdom, 5Department of Musculoskeletal Surgery, Imperial College, London, United Kingdom

Localised SAR around CoCr hip implants at 1.5T and 3T result in SAR10g exceeding the established limits. This is not necessarily worse at 3T and depends upon body shape and position within the RF transmit coil.

Magnetic Resonance Imaging findings in symptomatic versus asymptomatic subjects following metal-on-metal hip resurfacing implants
Catherine L Hayter1, Matthew F Koff1, Edwin P Su2, Kevin M Koch3, Parina Shah1, Stephanie L Gold1, and Hollis G Potter1
1Department of Radiology and Imaging - MRI, Hospital for Special Surgery, New York, New York, United States, 2Center for Hip Pain and Preservation, Hospital for Special Surgery, New York, New York, United States, 3Applied Science Laboratory, General Electric Healthcare, Waukesha, Wisconsin, United States

Metal-on-metal (MOM) hip resurfacing can be associated an adverse local tissue response (ALTR) which may manifest as synovitis or osteolysis. The purpose of this prospective, observational study was to review patterns of osteolysis and synovitis in symptomatic and asymptomatic individuals following MOM hip resurfacing. Synovitis was detected in a similar proportion of symptomatic and asymptomatic patients. Osteolysis was only detected in symptomatic individuals. The volume of synovitis was significantly higher in subjects with ALTR (p=0.01), as were levels of serum Cr (p=0.045) and Co (p=0.01). In the ALTR group there was a significantly higher proportion of females (p=0.048) and subjects with implants with abnormal acetabular component alignment (p=0.03). MRI is the most suitable non-invasive means by which to screen symptomatic and asymptomatic patients for the presence of synovitis. MRI can differentiate individuals with a normal pseudocapsule from those patients with synovitis, which, in combination with clinical findings and serum ion levels, will help to guide patient management. The finding of a high volume of synovitis on MRI should alert the clinician towards the need for close patient monitoring and possible revision surgery, particularly in the setting of elevated serum ion levels, female sex and abnormal component alignment.

MRI findings in patients with unexplained pain following metal-on-metal total hip arthroplasty and hip resurfacing arthroplasty
Catherine L Hayter1, Matthew F Koff1, Stephanie L Gold1, Giorgio Perino2, Kevin M Koch3, and Hollis G Potter1
1Hospital for Special Surgery, Department of Radiology and Imaging - MRI, New York, New York, United States, 2Hospital for Special Surgery, Department of Pathology and Laboratory Medicine, New York, New York, United States, 3Applied Science Laboratory, General Electric Healthcare, Waukesha, Wisconsin, United States

Metal on metal (MOM) prostheses may be complicated by aseptic lymphocyte-dominated vasculitis-associated lesions (ALVAL), which can manifest as synovitis or osteolysis. The purposes of this study were to review patterns of synovitis and osteolysis in subjects with pain following MOM hip resurfacing arthroplasty (RSA) and MOM total hip arthroplasty (THA) and correlate the MRI findings with results at revision surgery. Synovitis was present in 77% of RSA and 86% of THA hips. Mean synovial volume was higher in the THA group; however, this did not reach significance (p=0.18). There was no difference in the incidence of osteolysis (p=0.17), synovitis (p=0.51) or extracapsular disease (p=0.67) between the two groups. 20 subjects underwent revision surgery, of which 12 were diagnosed with ALVAL. Subjects with ALVAL had a significantly higher mean volume of synovitis (p=0.04) compared to those without ALVAL. Extracapsular disease and muscle edema were only detected in subjects with ALVAL. MRI is a useful assessment tool in patients with pain following MOM hip arthroplasty. MRI can detect synovitis, extracapsular disease and osteolysis, which may indicate ALVAL at revision surgery. Early results suggest that the most reliable MRI signs of ALVAL are extracapsular disease, high volumes of synovitis and intramuscular edema.

1419.   Measurement of concentrations of metal ions in pseudotumours close to metal-on-metal hips
Jessica Winfield1, and Donald McRobbie1
1Imperial College Healthcare NHS Trust, London, United Kingdom

We present a method to use MRI to measure concentrations of metal ions in fluid-filled pseudotumours near metal-on-metal (MoM) hips. The method uses 3D gradient echo sequences which exhibit only moderate metal artefacts when a high receive bandwidth is employed. Measurements of T1 relaxation times can be used to place upper limits on concentrations of metal ions in fluid-filled lesions. The study forms part of the long-term follow-up of patients with painful and well-functioning MoM hips in order to investigate the clinical significance of pseudotumours and elevated levels of metal ions.

1420.   Monitoring the delivery of therapeutic agents from antibiotic-loaded bone cement with contrast-enhanced MRI
Qingwei Liu1, Morgan B Giers2, Alex McLaren3, Christopher S Estes3, Michael R Caplan4, Gregory H Turner1, and Ryan Y McLemore3
1Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, United States, 2Harrington Department of BioMedical Engineering, Arizona State University, Tempe, AZ, United States, 3Orthopaedic Residency, Banner Good Samaritan Medical Center, Phoenix, AZ, United States, 4School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, United States

Periprosthetic infection is a devastating complication of joint replacement. Traditional local delivery experiments have been explored in vitro, but it is more important to study actual drug distribution in vivo. In this study, we used contrast enhanced MR imaging to track the delivery of small molecules through the complex delivery environment of bone, local tissues, and local blood flow. The elution of Gd marked drugs was observed after the surgery, which clearly showed continuous delivery of drugs in the tissue. The MRI T1 map technique was proved to be able to track the distribution of antibiotics in orthopaedic wounds.

1421.   Dental age estimation of living persons: comparison of MRI with the gold standard, the orthopantomogram
Pia Baumann1,2, Thomas Widek1, Heiko Merkens1, Julian Boldt3, Andreas Petrovic1,4, Barbara Kirnbauer5, Norbert Jakse5, and Eva Scheurer1,2
1Ludwig Boltzmann Institute for Clinical-Forensic Imaging, Graz, Austria, 2Medical University, Graz, Austria, 3Department of Prosthodontics, Julius Maximilians University, Würzburg, Germany, 4University of Technology, Institute of Medical Engineering, Graz, Austria, 5University Clinic for Oral and Maxillofacial Medicine, Graz, Austria

Dental age estimation is important for forensic age estimation in living adolescents which to date is based on the evaluation of an orthopantomogram. However, the use of ionizing radiation without medical indication is not permitted in many countries. In this study, MRI was compared to the orthopantomogram regarding dental development. The developmental stages could well be differentiated in MRI. While mineralization in the MRI tended to be associated with stages higher than in the orthopantomogram, eruption showed an almost perfect correlation between both methods. These results show that MRI might replace the orthopantomogram for dental age estimation in the future.

1422.   In-vivo high-resolution MRI of the Jaw Bone
Jakob Kreutner1, Andreas J. Hopfgartner2, Julian Boldt3, Kurt Rottner3, Daniel Haddad1, Ernst J. Richter3, and Peter M. Jakob1,2
1Research Center Magnetic-Resonance-Bavaria, Würzburg, Germany, 2Experimental Physics 5, University of Würzburg, Würzburg, Germany, 3Prosthodontics, Dental School, University of Würzburg, Würzburg, Germany

Planing of dental implants requires precise knowledge about dimensions of the defect and bone strength at this position. This work shows that MRI is capable to clearly depict the nerve canal running in the mandbile as well as resolving the trabecular microstructure within a reasonable scan time in vivo. Thus MRI has the potential to provide further information to choose an appropriate therapy.

1423.   Assessment of Apical Periodontitis by Size Comparison between MRI and CBCT
Elena Sophia Schreiber1,2, Anna-Katinka Bracher1, Erich Hell3, Johannes Ulrici3, Margrit-Ann Geibel2, Leif-Konradin Sailer4, and Volker Rasche1
1Department of Internal Medicine II, University Hospital of Ulm, Ulm, BW, Germany, 2Department of Oral and Maxillofacial Surgery, University Hospital of Ulm, Ulm, BW, Germany, 3Sirona Dental Systems GmbH, Bensheim, Germany, 4DOC Praxisklinik im Wiley, Neu-Ulm, Germany

The identification of the culprit lesion in apical periodontitis is often difficult due to the only limited performance of X-ray based techniques. MRI was applied in 30 patients and the results were qualitatively and quantitatively compared with cone beam CT images. MRI appears to reflect the actual size of the lesion much better than X-ray images and hereby an improvement of identification of the apical periodontitis can be achieved.

1424.   Computerized Quantification of Inflammatory Activity in Ankylosing Spondylitis
James F Griffith1, Defeng Wang1, Yi-Xiang Wang1, Shi Lin1, Min Deng1, Lai-Shan Tam2, and Edmund K Li2
1Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, 2Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong

Currently no method exists to objectively quantify spinal inflammation in ankylosing spondylitis (AS). Typically inflammation in AS involves the vertebral body corner areas. Several subjective scoring systems for spinal inflammation in AS exist. The proposed computerized quantification method automatically isolates the vertebral body corner area as well as the non-corner area of the vertebral body, excluding the basi-vertebral vein area. The entire process can be completed in 8 minutes. This method is reliable, seems sensitive to change and compares to clinical assessment more favorably than subjective assessment.
Traditional Poster Session - Musculoskeletal

Click on to view the abstract pdf. Click on to view the poster (Not all posters are available for viewing.)
Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

1425.   Monitoring exercise-induced muscle changes using Diffusion Tensor Imaging, with and without caffeine
Conrad Rockel1,2, Andrew Davis2,3, Greg Wells4, and Michael Noseworthy1,2
1School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada, 2Imaging Research Centre, St Joseph's Healthcare, Hamilton, Ontario, Canada, 3Medical Physics and Applied Radiation Science, McMaster University, Hamilton, Ontario, Canada, 4Faculty of Physical Education and Health, University of Toronto, Toronto, Ontario, Canada

The time course of diffusion within calf muscle following exercise was investigated using DTI in the presence and absence of caffeine. Two trials were performed, each involving two exercise sets one hour apart. In one trial, caffeine was consumed after the first exercise set. Eight DTI volumes were collected both prior to and immediately after each set. In gastrocnemius, post-exercise mean diffusivity(MD) and eigenvalues were approximately baseline, followed by a rapid increase and subsequent gradual decline. Soleus post-exercise MD and eigenvalues increased slightly from rest and appeared stable across time. The presence of caffeine did not affect diffusivity values.

1426.   Using DTI to Assess the Effect of Diet or Exercise in Elderly Obese Women
Armen A. Gharibans1, Curtis L. Johnson1, Danchin D. Chen1, Dolores D. Guest2, Christie L. Ward3, Bhibha M. Das3, Ellen M. Evans3, and John G. Georgiadis1
1Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States, 2Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL, United States, 3Kinesiology, University of Georgia, Athens, GA, United States

Diffusion tensor imaging (DTI) was used to study microstructural changes in the thigh muscles of elderly, obese women before and after a diet or exercise intervention. Nineteen subjects underwent either a diet or a weight-stable exercise four-month program. Both weight loss and exercise regimens alter muscle microstructure and modify various DTI measures, but exercise impacts muscle quality more than weight loss.

1427.   Optimization of filter size for HARP analysis of lower leg muscle
Amanda K. W. Buck1, Justin Montenegro1, Jared Godar1,2, and Bruce M. Damon1
1Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 2Department of Molecular Physiology and Biophysics, Vanderbilt University

Optimization of filter dimensions for HARP processing of cine tagged MRI data of contracting calf muscle with signal loss due to physiologic structures.

1428.   Automated whole body muscle quantification based on a 10 min MR-exam
Anette Karlsson1,2, Olof Dahlqvist Leinhard2,3, Anna Vallin2, Thobias Romu1,2, and Magnus Borga1,2
1Department of Biomedical Engineering, Linköping University, Linköping, Sweden, 2Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden, 3Depts of Radiation Physics, Linköping University and Radiation Physics, UHL County Council of Ostergotland, Linköping, Sweden

We have previously developed methods where intensity normalized water and fat separated images can be used for fat quantification. This approach has now been developed for performing automatic muscle quantification in 3D whole body volumes. A water volume of a subject is used as a prototype where the muscles are segmented manually. The prototype volume is deformed to match the water volume of the target image using non-rigid registration. The muscle mask of the prototype is also deformed giving an automatic muscle mask to the target image which can be used for quantification.

1429.   Comparison of 2- and 3-Point Dixon Muscle Fat Content with Chemical Analysis
Monika Gloor1, Evelyn Ilg Hampe2, Dirk Fischer3, Oliver Bieri1, and Arne Fischmann4
1University of Basel Hospital, Radiological Physics, Basel, Basel, Switzerland, 2Gesundheitsdepartement Basel-Stadt, Basel, Switzerland, 3University of Basel Hospital, Neurology, Basel, Switzerland, 4University of Basel Hospital, Neuroradiology, Basel, Basel, Switzerland

Fat quantification based on 2- and 3-point Dixon techniques is a promising measure for clinical trials e.g. in muscular dystrophies, where normal muscle is replaced by fatty and connective tissue. However, it is unclear which chemical components are exactly accounted for by MT-determined fat fractions. In this work, fat content in several meat samples is determined by an extended 2-point Dixon and a 3-point Dixon technique and compared to a chemical analysis of triglyceride and fatty acid content of the samples. The results are of interest for the interpretation of previous and future quantitative MR measurements of muscle fat content.

1430.   Validation of a practical approach to muscle T2 determination in fatty-infiltrated skeletal muscles
Noura Azzabou1,2, Paulo Loureiro de Sousa1,2, and Pierre G Carlier1,2
1NMR Laboratory, Institute of Myology, Paris, France, 2NMR Laboratory, CEA, I²BM, MIRCen, IdM, Paris, France

In the field of neuromuscular disorders, muscle water T2 measurement is proposed as a marker of disease progression. However in case of fat infiltrated muscle since T2 values are higher in fat than in water, mono-exponential fits of non-fat-suppressed echo trains will result in T2 values that principally reflect the degree of fat infiltration. Yet fat-suppression often fails over large volumes. Here, we propose a solution to address this issue, based on voxel selection using B1 mapping and tri-exponential deconvolution in non-fat-suppressed multiple echo series, and validate the method in lower limb images of patients.

1431.   Gender-dependent effects of dietary-induced changes of the muscle in an animal model for sarcopenic obesity
Claudia Fellner1, Christine Hechtl1, Roland Büttner2, Okka H. Hamer1, Christian Stroszczynski1, and Cornelius Bollheimer2
1Institute of Radiology, University Medical Center Regensburg, Regensburg, Germany, 2Internal Medicine I, University Medical Center Regensburg, Regensburg, Germany

To assess dietary-induced changes of the muscle, 20 female high fat fed rats (HFR) and 12 female control animals (CR) fed with standard diet as well as 8 male HFR and 14 male CR underwent MRI and MRS at the age of 16 months. Maximum cross sectional area of the M. quadriceps was smaller in HFR compared with CR, HFR yielded increased lipid content and prolonged T2 relaxation times. Although all effects were seen in both genders, dietary-induced differences were significantly more pronounced in male than in female rats indicating relevant gender-depenent differences in our animal model of sarcopenic obesity.

1432.   Quantification of lower limb muscle fatty atrophy by 3-point Dixon MRI in chronic neuromuscular diseases - a potential outcome measure
Jasper M Morrow1, Christopher DJ Sinclair1,2, Arne Fischmann2, Xavier Golay2, Tarek A Yousry1,2, Mary M Reilly1, Michael G Hanna1, and John S Thornton1,2
1MRC Centre for Neuromuscular Diseases, Dept. of Molecular Neurosciences, UCL Institute of Neurology, University College London, London, United Kingdom, 2Academic Neuroradiological Unit, Dept of Brain Repair and Rehabilitation, UCL Institute of Neurology, University College London, London, United Kingdom

We measured lower-limb thigh and calf muscle fat-fractions by 3-point Dixon MRI in 20 Charcot-Marie-Tooth disease 1A (CMT1A) patients, 20 patients with inclusion body myositis (IBM) and 28 healthy controls. Mean %fat-fractions were increased in both patient groups relative to controls for all calf muscles (p<0.01) and in IBM patients for all thigh muscles (p<0.001). Relevant remaining cross-sectional muscle area, a composite measure accounting for both muscle atrophy and fat replacement, was highly correlated (R=0.57-0.90, p <0.001) with accurate functional measures of knee and ankle strength. Dixon lower-limb muscle-fat assessment shows promise as a trial outcome measure in neuromuscular diseases.

1433.   Natural progression of fatty infiltration and beneficial effects of non-pharmaceutical intervention in FSHD detected by quantitative MRI
Barbara Janssen1, Nicoline Voet2, Rob Arts1, Christine Nabuurs1, George Padberg3, Alexander Geurts2, Baziel van Engelen3, and Arend Heerschap1
1Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands, 2Rehabilitation, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands, 3Neurology, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands

To assess natural progression towards a diseased state in FSHD-patients, and effects of Cognitive Behavioral Therapy and Aerobic Exercise Training (AET) we used muscle fraction measured by 1H¬-MRI of the thigh muscles as non-invasive biomarkers. A decrease in muscle fraction, corresponding to an increase in fatty infiltration, could be noticed in controls after a four month period of usual care. This increase was largest in intermediate affected muscles. Interventions appeared to beneficial to patient since no significant increase in fat infiltration could be noticed after four months after intervention, heavily affected muscles even showed an increase in muscle fraction.

1434.   Changes in Muscular Lipid Storage After Diet or Exercise in Elderly Obese Women
Curtis L. Johnson1, Danchin D. Chen1, Diego Hernando2, Dolores D. Guest3, Christie L. Ward4, Bhibha M. Das4, Ellen M. Evans4, and John G. Georgiadis1
1Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States, 2Radiology, University of Wisconsin, Madison, WI, United States,3Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL, United States, 4Kinesiology, University of Georgia, Athens, GA, United States

Proton magnetic resonance spectroscopy (MRS) was used to study lipid storage in the thigh muscles of elderly, obese women before and after a diet or exercise four-month intervention program. Subjects were divided in two groups, a diet group who lost 10% in body weight or a weight stable exercise group. The exercise group showed significant changes in EMCL and total lipid concentrations, with no change in IMCL concentration. The diet group showed no significant changes in lipid storage with intervention.

1435.   Phosphorus MRS study of a murine model of peripheral arterial disease
Vladimír Mlynárik1, Maxime Pellegrin2, Cristina Cudalbu1, Lucia Mazzolai2, and Rolf Gruetter1,3
1Laboratory of Functional and Metabolic Imaging, EPFL, Lausanne, Switzerland, 2Service of Angiology, University Hospital of Lausanne, Lausanne, Switzerland, 3Departments of Radiology, Universities of Lausanne and Geneva, Switzerland

Diminished perfusion in peripheral arterial disease leads to the development of ischemia, which is thought to initiate angiogenesis, arteriogenesis and enhanced muscle metabolism. Our model of ligating right common iliac artery in mice led to a significant decrease of PCr/lower case Greek gamma-ATP measured by localized phosphorus MRS in femoral muscles of the operated leg compared to sham-operated controls one week after surgery. The PCr/lower case Greek gamma-ATP ratio was also reduced in the contralateral leg. Five weeks after operation this ratio increased in both legs to levels slightly higher than those in sham-operated animals. There was no significant difference between sedentary and treadmill-exercised animals.

1436.   Skeletal muscle metabolism measured at rest and after excercise in obese non-diabetic subjects
Ladislav Valkovic1,2, Barbara Ukropcova3, Marek Chmelik1, Miroslav Balaz3, Martin Tkacov1, Wolfgang Bogner1, Albrecht Ingo Schmid4, Ivan Frollo2, Iwar Klimes3, Erika Zemkova5, Jozef Ukropec3, Siegfried Trattnig1, and Martin Krššák6
1MR Centre of Excellence, Department of Radiology, Medical University of Vienna, Vienna, Austria, 2Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia, 3Obesity section, Diabetes and Metabolic Disease Laboratory, Institute of Experimental Endocrynology, Slovak Academy of Sciences, Bratislava, Slovakia, 4Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria, 5Faculty of Physical Education and Sport, Commenius University, Bratislava, Slovakia, 6Division of Endocrynology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria

In this study different parameters of muscle energy and oxidative metabolism in quadriceps of overweight to obese healthy subjects (n=8) were compared. Maximal oxidative flux (Qmax) was measured by time resolved 31P-MRS during post exercise recovery. Six minutes of exercise at ~30% of MVC resulted in substantial decrease of PCr without alteration of pH. Mean value of Qmax reached 0.48±0.10 mM/s. Basal flux through ATPase (FATP) at rest was measured by magnetization transfer 31P-MRS experiment. Mean value of FATP was 0.23±0.09 mM/s. At this stage positive trend, but no significant correlation (r=0.535, p=0.19) was detected between Qmax and FATP.

1437.   Measurement of post-exercise glycogen resynthesis following ingestion of glucose polymers with different molecular weights and osmolality: A 13C MRS study.
Mary Charlotte Stephenson1, Frances Gunner2, Paul L Greenhaff2, Peter G Morris1, and Ian A MacDonald2
1SPMMRC, School of Physics and Astronomy, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, 2School of Biomedical Sciences, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom

Ingestion of a high molecular weight glucose polymer (HMW) with low osmolality leads to greater early increases in blood glucose and insulin compared with a glucose polymer with lower molecular weight (LMW) and higher osmolality. This study aims to use 13C MRS to measure differences in muscle glycogen resynthesis rates following ingestion of three different drinks: HMW, LMW, and flavoured water. Despite significant increases in glycogen levels following HMW and LMW ingestion, rates of glycogen resynthesis were smaller than expected and were not significantly different between the two glucose polymers. No glycogen resynthesis was found following ingestion of flavoured water.

1438.   Magnetization Transfer Effects from Water to Metabolites in Human Skeletal Muscle Observed by Non-Water-Suppressed MR Spectroscopy
Erin Leigh MacMillan1, Chris Boesch1, and Roland Kreis1
1Depts Clinical Research and Radiology, University of Bern, Bern, Switzerland

Non-water suppressed proton MRS via the metabolite cycling technique was applied to human soleus and tibialis anterior muscles with short TE PRESS at 3T revealing additional features in the downfield region. In addition, magnetization transfer of these downfield resonances, and the upfield creatine CH2 and CH3 peaks, was investigated by selectively inverting the water resonance with increasing mixing times. Changes in magnetization of the downfield resonances and creatine peaks in the soleus were similar to those in the tibialis anterior, which exhibits residual dipolar coupling. These results may help to gain a deeper understanding of underlying magnetization transfer phenomena.

Combined automatic segmentation of fat and muscle compartments with T1 and T2* measurements using a triple-angle multiple gradient-echo acquisition technique
Benjamin Leporq1, Yann Le Fur2, Patrick Cozzone2, Olivier Beuf1, and David Bendahan2
1CREATIS; CNRS UMR 5220; INSERM U1044; INSA-Lyon; UCBL Lyon 1, Villeurbanne, Rhône-Alpes, France, 2CRMBM; CNRS UMR 6612; Université Aix-Marseille, Marseille, PACA, France
Due to its sensitivity to key processes in the diseased muscle such as edema and fat infiltration, MRI is emerging as a suitable quantitative method which could provide reliable surrogate markers of disease severity and progression. The aim of this work was to evaluate the feasibility of 3D segmentation of fat and muscular tissue using a triple-angles multiple gradient-echo acquisition. Our approach includes a complex-based technique for fat volume fraction (FVF) quantification with independent measurements of fat and water T1 and T2*and corrections from T1-related bias and spectral complexity of fat.

1440.   From food to muscle: Dietary-induced effects on muscle in a longitudinal animal study
Claudia Fellner1, Christine Hechtl1, Roland Büttner2, Okka H. Hamer1, Christian Stroszczynski1, and Cornelius Bollheimer2
1Institute of Radiology, University Medical Center Regensburg, Regensburg, Germany, 2Internal Medicine I, University Medical Center Regensburg, Regensburg, Germany

Dietary-induced changes on quadriceps muscles were investigated in 20 female high fat fed rats (HFR) and 12 control rats (CR) fed with standard diet, who underwent MRI and MRS at the age of 6, 12, and 16 months. Until the age of 16 months, increased accumulation of body weight in HFR relative to CR was accompanied by a larger lipid content in quadriceps muscles – without changing the cross sectional area of the muscle. During this period of time, age-related and dietary-induced changes of the T2 relaxation times in the muscle can not be explained exclusively by an increased lipid content.

1441.   Characterization of the time course of MR relaxation parameters for ageing blood
Andreas Petrovic1,2, Kathrin Ogris3, Eva Hassler3,4, Rudolf Stollberger5, and Eva Scheurer3,4
1Institute of Medical Engineering, University of Technology Graz, Graz, Austria, Austria, 2Ludwig Boltzmann Institute for Clinical Forensic Imaging, Graz, Austria, Austria,3Ludwig Boltzmann Institute for Clinical Forensic Imaging, 4Medical University Graz, 5University of Technology Graz

In legal medicine the detection of hematomas in subcutaneous fatty tissue and especially the estimation of their age is highly relevant. The time dependent development of the MRI signal of blood is well known and described in the literature for intracranial hematomas for which a semi-quantitative staging scheme was defined. In this work we continuously measured the relaxation times T1, T2 and T2* of human blood samples to characterize the actual time course. Our measurements confirm the findings from the literature but also further provide valuable insight on the interdependence of the relaxation parameters.

1442.   Multi-parametric MRI characterization of inflammation in murine skeletal muscle
Nathan D Bryant1, Ke Li1, Mark Does2, Daniel Gochberg1, Thomas Yankeelov1, Jane Park3,4, and Bruce Damon1,4
1Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 2Biomedical Engineering, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, 3Molecular Physiology and Biophysics, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 4Co-Senior Author

Healthy skeletal muscle was compared to inflammation in the contralateral quadriceps muscles of mice. T2, indices of diffusion, quantitative magnetization transfer, and dynamic contrast enhancement (DCE) MRI data were acquired during the same imaging session. The edematous muscle exhibited a significant increase in T2, apparent diffusion coefficient (ADC) and the DCE estimate of the interstitial volume, while a concomitant decrease was observed in the proton pool ratio. The aim of this study is to provide a basis for understanding how inflammation, in isolation from complex pathology, influences the quantitative MRI parameters that are commonly used to characterize muscle disease.

1443.   Water Specific Magnetization Transfer in Skeletal Muscle using MT-IDEAL
Robert L. Janiczek1,2, Christopher D.J. Sinclair2, Giulio Gambarota3, Xavier Golay2, Rexford D. Newbould4, and John S. Thornton2
1Global Imaging Unit, GlaxoSmithKline, London, United Kingdom, 2Institute of Neurology, University College London, London, United Kingdom, 3Pharmaceutical and Biological Sciences, Université de Rennes 1, Rennes, France, 4Imanova Ltd., London, United Kingdom

A reduced magnetization transfer (MT) effect has been observed in muscles affected by neuromuscular diseases due to a combination of lipid infiltration, edema, and/or macromolecular differences relative to healthy muscle. Lipid infiltration can therefore mask MT changes due edema and biologically important macromolecular abnormalities. This work presents a technique, MT-IDEAL, that combines a chemical-species separation imaging technique, IDEAL, with an MT imaging acquisition. MT-IDEAL uses multiple echoes to increase SNR as well as produce fat fraction, T2*, and water-isolated MTR maps with no scan time penalty.

1444.   Simultaneous Detection of Blood Flow, MT Asymmetry, and MT Ratio in Human Skeletal Muscle
Sung-Hong Park1, and Kyongtae Ty Bae1
1Radiology, University of Pittsburgh, Pittsburgh, PA, United States

In this article we evaluated the feasibility of alternate ascending/descending directional navigation (ALADDIN), a new imaging technique that provides interslice perfusion-weighted and MT asymmetry images, on human skeletal muscle. Subtraction artifacts in ALADDIN MT asymmetry images were suppressed by averaging signals over the readout gradient polarities. ALADDIN PW and MT asymmetry signals measured in muscle were about 10% and 30%, respectively, of those in brain, while MT ratio of muscle was similar to that of brain. Further studies are necessary to investigate clinical usefulness of simultaneous acquisition of blood flow, MT asymmetry, and MT ratio with ALADDIN in skeletal muscle.

1445.   3T multiecho gradient-recalled echo BOLD MRI with high reproducibility for serial assessment of limb muscle oxygenation
Erik Hedstrom1,2, Ashish S Patel2,3, Tobias Voigt1,4, Bijan Modarai2,3, Tobias Schaeffter1,2, Alberto Smith2,3, and Eike Nagel1,2
1Division of Imaging Sciences and Biomedical Engineering, King's College London, London, Greater London, United Kingdom, 2BHF Centre of Research Excellence and NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Fo, London, United Kingdom, 3Academic Department of Surgery, King's College London, London, Greater London, United Kingdom, 4Philips Research, Clinical Research Europe

BOLD MRI of lower limb muscle has shown low reproducibility using relatively low-resolution EPI-readout GRE sequences, which may partly be related to partial volume effects. We propose a high-resolution GRE sequence without EPI readout to decrease partial volume effects and test it in elderly men without limb disease during transient ischaemia induced by cuffing to suprasystolic pressure. We show low intrascan variability and high interscan reproducibility for measurement of T2* in limb muscle, indicating that serial assessment of limb muscle oxygenation is possible.

1446.   'Investigation of Human Quadriceps Variation on Resting Muscle Stiffness and Brain Activation During Contraction
Paul Kennedy1, Scott Semple1, Calum Gray1, Annette Cooper1, Eric Barnhill1, Colin Brown2, David Donaldson3, Edwin van Beek1, Pete Hoskins4, Dieter Klatt5, Ingolf Sack5, Jürgen Braun5, Carolyn Greig4, Angus Hunter6, and Neil Roberts1
1Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, United Kingdom, 2The Mentholatum Company, East Kilbride, Glasgow, United Kingdom, 3Department of Psychology, University of Stirling, Stirling, United Kingdom, 4University of Edinburgh, 5Charité University, Berlin, Germany, 6Health and Exercise Sciences Research Group, University of Stirling, Stirling, United Kingdom

We present our ongoing work on the investigation of human skeletal muscle using MRI. We outline the variations in muscle morphology seen and how they correlate with stiffness measurements obtained by magnetic resonance elastography.

1447.   Pitfalls in Cuff-induced Ischemia Studies Using BOLD MRI
David K.W. Yeung1, James F Griffith2, Heather T Ma2,3, and Alvin F.W. Li4
1Imaging and Interventional Radiology, Prince of Wales Hospital, Shatin, HKSAR, Hong Kong, 2Imaging and Interventional Radiology, The Chinese University of Hong Kong, Shatin, Hong Kong, 3Department of Electronic and Information Engineering, Harbin Institute of Technology, China, 4Imaging and Interventional Radiology, The Chinese University of Hong Kong, Shatin

Muscle perfusion may be studied using the BOLD technique. This method relies on an air-cuff to induce reactive hyperemia. However, oxygen in air is a paramagnetic molecule and whether an inflated air-cuff has an effect on T2* signal measurement is not known. This study attempts to answer this question and offers solutions to correct for aberrant T2* signal changes.
Traditional Poster Session - Musculoskeletal

MSK Technical
Click on to view the abstract pdf. Click on to view the poster (Not all posters are available for viewing.)
Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

1448.   Measurements of child's skeletal age using a 0.3 T open compact MRI system
Yasuhiko Terada1, Saki Kono1, Daiki Tamada1, Tomomi Uchiumi1, Katsumi Kose1, Ryo Miyagi2, Eiko Yamabe2, and Hiroshi Yoshioka2
1Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki, Japan, 2Department of Radiological Sciences, University of California Irvine, Irvine, CA, United States

To measure childfs skeletal age, which is a standard measure of childfs growth status, an open compact MRI system was optimized for childfs hand imaging. Left hands of 93 healthy children volunteers were imaged using a 3D coherent gradient-echo sequence. Despite the limited measurement time (2 min 44 s), each bone was well resolved in the MRI images, revealing the validity of the system. Furthermore, segmented volume of carpal bones highly correlates with skeletal age (r = 0.904 for boys and 0.917 for girls). This reveals that the bone volume is a new, good indicator of childfs maturity.

1449.   High Resolution PDw-TSE of the ankle with the use of a flexible high density receive array at 7Tesla.
Fredy Visser1,2, Mies Korteweg1, Michel Italiaander1, Peter Luijten1, and Dennis Klomp1
17 Tesla, UMC, Utrecht, Utrecht, Netherlands, 2Philips Healthcare, Best, Brabant, Netherlands

The aim of this study is to develop a High Resolution TSE PD-weighted sequence for ankle imaging. We show that routine clinical TSE sequence in MSK is feasible at 7T . The combination of the high SNR at 7Tesla and a 32 channel high density flexible receive array has the potential to make the next step forward in High Resolution musculoskeletal imaging.

1450.   Knee MRI with in situ mechanical loading using prospective motion correction
Thomas Lange1, Julian Maclaren1, Michael Herbst1, Kaywan Izadpanah2, and Maxim Zaitsev1
1Department of Radiology, University Medical Center Freiburg, Freiburg, Germany, 2Department of Orthopedic and Trauma Surgery, University Medical Center Freiburg, Freiburg, Germany

Since chondromalacia is associated with altered mechanical cartilage properties, the response of tissue parameters such as cartilage thickness or relaxation times to loading is of particular interest. However, knee MRI studies with in situ loading are hampered by subject motion. Using prospective motion correction based on optical tracking, MRI of the patellofemoral joint with in situ mechanical loading is demonstrated. Results indicate that the rigid-body approximation required for prospective correction with optical motion tracking is fulfilled for the patellofemoral compartment and that with presaturation of the posterior knee compartment an image quality similar to an unloaded setup can be obtained.

1451.   Automatic Landmark for MRI Scanners
Robert D. Darrow1, Eric W. Fiveland1, Xiaodong Tao2, Ambey Govenkar3, Xiaofeng Liu1, W. Thomas Dixon1, Michael S. Jansen4, and Ileana Hancu1
1GE Global Research, Niskayuna, N.Y., United States, 2GE Healthcare, Beijing, China, 3Extenprise, Inc., Pune, India, 4GE Healthcare, Milwaukee, WI, United States

An automated landmark system, positioning anatomy of interest at magnet isocenter, can simplify a MR exam. It can also ensure automatic scan plane prescription algorithms are provided with the correct input. A system is presented that localizes the imaging coil along the Superior/Inferior axis, enabling automatic translation of coil center from home position to magnet isocenter. Once the anatomy of interest is at isocenter, scout images are acquired and processed, localizing the coil relative to the patient, and enabling computation of the scan volume center. This dual localization permits imaging with optimal positioning, while completely eliminating the manual landmark.

1452.   Correlation of high-resolution interleaved water-fat MR imaging of finger joints with micro-CT
Wingchi Edmund Kwok1,2, Zhigang You1, Johnny Monu1, Gwysuk Seo1, and Amy Lerner3
1Department of Imaging Sciences, University of Rochester, Rochester, NY, United States, 2Rochester Center for Brain Imaging, University of Rochester, Rochester, NY, United States, 3Department of Biomedical Engineering, University of Rochester, Rochester, NY, United States

To address insufficient resolution and chemical-shift artifacts that can hinder MRI evaluation of arthritis in finger joints, an interleaved water-fat (IWF) sequence without chemical-shift artifacts and a dedicated RF coil were used for high-resolution finger MRI. In this study, we evaluated this technique in the depiction of bone structures by correlating MR images of cadaver fingers with micro-CT that served as the gold standard. IWF images provided accurate depiction of bone structures and abnormalities as seen in micro-CT, and avoided false appearance of erosions. High-resolution IWF imaging should be useful for the diagnosis, treatment assessment and pathogenesis studies of arthritis.

1453.   Effect of Static- and Cyclic-loading on Meniscus MR Relaxation Times
Karupppasamy Subburaj1, Deepak Kumar1,2, Richard B Souza1,2, Hamza Alizai1, Xiaojuan Li1, Thomas M Link1, and Sharmila Majumdar1
1Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States, 2Physical Therapy and Rehabilitation Science, University of California San Francisco, San Francisco, CA, United States

The mechanical function of the meniscus largely depends on the structural and molecular integrity of its matrix, composed of a network of collagen fibers (Type I) immobilizing proteoglycans (PG). Recent studies have shown the potential of quantitative MR imaging, including T2 and T1ρ quantifications for studying biochemical composition of meniscus. The purpose of this study was to determine the response of PG and collagen, which are responsible for the compressive stiffness and tensile strength of meniscus [5], respectively, to static- and cyclic-loading using magnetic resonance (MR) relaxation times (T1ρ and T2) in young healthy adults.

1454.   Power Efficient Magnetization Inversion Using Driven Adiabatic RF Pulses
Michael Carl1, and Jiang Du2
1GE Healthcare, San Diego, CA, United States, 2University of California, San Diego, United States

We developed adiabatic pulses for non-selective inversion, which actively drive the magnetization vector along a path parallel to the effective B1 trajectory using driven adiabatic inversion (DAI) pulses. These pulses may play a particularly important role in IR prepared 3DUTE imaging, where the minimum TR (and hence scan-time) is limited by the SAR imparted by the adiabatic inversion pulses. Simulations, and phantom test were used to verify the inversion efficiency and SAR performance compared to conventional Silver-Hoult IR pulses.

1455.   Effective TE for Radial FID Sequences
Michael Carl1, and Graeme McKinnon2
1GE Healthcare, San Diego, CA, United States, 2GE Healthcare, Waukesha, WI, United States

There exists a variety of inconsistent definitions of TE for short echo time sequences throughout the literature. We investigate via theoretical analysis, Bloch simulations, and phantom experiments an appropriate definition of TE for short echo time FID sequences. Erroneous definitions of TE will underestimate the amount of T2 decay and off-resonance phase evolutions, which may result in errors in assessing T2 and/or resonance frequency of tissues.

1456.   Progressive Dual-Kriging for 2D and 3D qMRI data interpolation
Delphine Perie1,2, Mohamed Aissiou1,2, Julien Gervais1,2, Francois Trocchu1, Gilles Beaudoin3, and Guillaume Gilbert4
1Mechanical Engineering, Ecole Polytechnique de Montreal, Montreal, Quebec, Canada, 2Research center, CHU Sainte-Justine, Montreal, Quebec, Canada, 3Physics and Biomedical Engineering, CHUM Hopital Saint-Luc, Montreal, quebec, Canada, 4MR Clinical Science, Philips Healthcare, Cleveland, OH, United States

The aim of this study is to validate the reconstruction of 2D and 3D images from low to high spatial resolution. We performed two quantitative MR acquisitions (low and high resolution) on bovine discs. We adopted the Dual-Kriging formulation and we introduced the technique of progressive Kriging. For each MR sequence, Kriging was compared to other interpolation techniques including the zero padding, nearest neighbour, bilinear and bicubic techniques. Progressive Dual-Kriging is a flexible technique that can be optimized to interpolate 2D and 3D data based on the signal distribution. The computation is relatively fast and the interpolation is better fitted to the signal distribution as opposed to other techniques.

1457.   Residual Dipolar Coupling - A Fundemental Tissue Parameter
Nikolaus M. Szeverenyi1, and Graeme M. Bydder1
1Radiology, University of California, San Diego, CA, United States

Residual dipolar coupling (RDC) provides an important contrast mechanism when imaging fibrocartilage. The presence of RDC produces change in T2* values and gives rise to the magic angle effect, providing angle dependent contrast between fiber structures. RDC should be viewed as a fundamental measurable tissue parameter, similar to a diffusion rate or T1 value. We have developed an imaging technique allowing the evaluation of this parameter on a per voxel basis. The RDC value provides a sensitive indicator reflecting the structure of fibrocartilage tissue, e.g. direction and distribution of fibers, how much collagen is present and state of hydration.

1458.   MR Monitoring of Minimally Invasive Delivery of Mesenchymal Stem Cells into the Porcine Intervertebral Disc
Monika Barczewska1, Joanna Wojtkiewicz1, Aleksandra Habich1, Miroslaw Janowski2,3, Zbigniew Adamiak4, Piotr Holak4, Hubert Matyjasik4, Jeff WM Bulte2,3, Wojciech Maksymowicz1, and Piotr Walczak2,3
1Neurology and Neurosurgery, Division of Neurosurgery, Faculty of Medical Sciences, University of Warmia and Mazury, Olsztyn, Poland, 2Radiology and Radiological Science, Johns Hopkins University, 3Institute for Cell Engineering, Johns Hopkins University, Baltimore, MD, United States, 4Surgery and Radiology, Faculty of Veterinary Medicine, University of Warmia and Mazury, Olsztyn, Poland

Degenerative disc disease is related to substantial morbidity and no treatment exists that can restore disc structure. Stem cell-based therapy is a new promising therapeutic approach; however, for the use of stem cells a precise and minimally invasive cell delivery procedure is of critical importance. We show here that MR monitoring can be used to verify the accurate delivery of cells and provide a detailed picture of initial cell engraftment and biodistribution in a clinically relevant fashion.

1459.   T1-T2 Cluster Analysis of Intervertebral Disc Sub-Structures
Alexander C. Wright1, Sung M. Moon1,2, Jonathon H. Yoder2, Edward J. Vresilovic2, and Dawn M. Elliott2
1Laboratory for Structural NMR Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, United States

High-resolution MRI (200 µm isotropic) at 7T was used to visualize the anatomy of the sub-structures of the human intervertebral disc, and T1 and T2 relaxation parameter maps were acquired on a specimen. Based on these, a T1-T2 cluster analysis revealed distinct differentiation of the disc sub-structures. A similar trend was observed even for T1- and T2-weighted images. These concepts were tested in vivo at 3T in order to assess their potential role as a grading scheme for disc degeneration.

1460.   Age-related assessment of intervertebral disc degeneration in the lumbar spine using gagCEST
Gopal Varma1, Fotini Kourtelidis1, Ananth Madhuranthakam1,2, David B Hackney3, Robert E Lenkinski1,2, and Elena Vinogradov1,2
1Radiology, Division of MR Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States, 2Radiology, UT Southwestern Medical Center, Dallas, TX, United States, 3Neuroradiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States

Early signs of intervertebral disc (IVD) degeneration are associated with a decrease in glycosaminoglycan (GAG) content. Recently, chemical exchange saturation transfer, i.e. gagCEST, has been used to assess GAG distribution in vivo. This work looks at application of gagCEST for analysis of IVDs from the lumbar spine of volunteers of varying age. The IVDs are grouped based on Pfirrmann grading, as well as age, and a decrease in gagCEST contrast is observed with increasing disc degeneration.

1461.   Sodium MR Imaging as a Marker for Achilles Tendinopathy
Vladimir Juras1,2, Christina Pressl1, Iris-Melanie Noebauer-Huhmann1, Stefan Zbyn1, Pavol Szomolanyi1, Stephan Domayer3, Ivan Frollo2, and Siegfried Trattnig1
1Department of Radiology, MR Centre of Excellence, Medical University of Vienna, Vienna, Austria, Austria, 2Department of Imaging Methods, Institute of Measurement Science, Bratislava, Slovakia, 3Department of Orthopedics, Medical University of Vienna, Vienna, Austria, Austria

Sodium MRI using 3D-GRE has been investigated as a possible marker for Achilles tendinopathy. Achilles tendinopathy is associated with an increase in proteoglycans and can be detected by sodium MR imaging which has been validated by in vitro study. Moreover, it was shown that the Achilles tendon is diffusely affected in Achilles tendinopathy.