Alberto De Luca^1,2, Maria Grazia D'Angelo³, Denis Peruzzo², Fabio Triulzi⁴, Alessandra Bertoldo¹, and Filippo Arrigoni^2
1Department of Information Engineering, University of Padova, Padova, Italy, ²Neuroimaging Lab, Scientific Institute IRCCS Eugenio Medea, Bosisio Parini (LC), Italy, ³Functional Rehabilitation Unit, Neuromuscular Disorders, Scientific Institute IRCCS Eugenio Medea, Bosisio Parini (LC), Italy, ⁴Department of Neuroradiology, Scientific Institute IRCCS Ca Granda Foundation - Ospedale Maggiore Policlinico, Milan, Italy

Limb girdle muscular dystrophies (LGMD) are a heterogeneous family of disorders characterized by the substitution of muscles with fat and fibrotic tissue. In this work we show the initial results of our acquisition protocol, that included DW-MRI, T₂ mapping and DIXON imaging, on two subtypes of LGMD (type 2A and 2B). Statistical tests and Pearson’s correlation were performed on parametric maps at single muscle level. Preliminary results show that multi-parametric MRI is promising in the characterization of LGMD subtypes on the thigh. Considered MRI techniques show different sensibilities to damages induced by muscular dystrophies and can be considered complimentary.

Koji Sagiyama¹, Yuji Watanabe², Ryotaro Kamei¹, Sungtak Hong³, Satoshi Kawanami², Yoshihiro Matsumoto⁴, and Hiroshi Honda^1
1Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan, ²Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan, ³Healthcare, Philips Electronics Japan, Fukuoka, Japan, ⁴Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan

A combination of single measurements would be necessary to improve the efficacy of evaluating the treatment effect in heterogeneous soft-tissue tumors. This study aimed to investigate the feasibility of direct voxel-by-voxel comparison of SUVs and ADCs with the PET/MR system in the evaluation of the treatment effect in soft-tissue tumors. The ADCs and SUVs were recorded on a voxel-by-voxel basis for all slices. The scatter plots clearly demonstrated significant difference between pre- and post-treatment. Multiparametric voxel-based analysis of SUVs and ADCs could be a promising tool for evaluating the treatment effect in soft-tissue tumors.

Taiki Nozaki¹, Atsushi Tasaki², Saya Horiuchi¹, Junko Ochi¹, Jay Starkey¹, Takeshi Hara³, Yukihisa Saida¹, Yasuyuki Kurihara¹, and Hiroshi Yoshioka^4
1Radiology, St.Luke's International Hospital, Tokyo, Japan, ²Orthopaedic Surgery, St.Luke's International Hospital, Tokyo, Japan, ³Intelligent Image Information, Gifu University, Gifu, Japan, ⁴Radiological Sciences, University of California, Irvine, Orange, CA, United States

Rotator cuff tear is a common cause of shoulder pain and disability. Minimally-invasive arthroscopic rotator cuff repair is increasingly popular for treatment of full-thickness rotator cuff tear. However, operative outcomes are far from perfect. Postoperative re-tears are associated with greater fatty degeneration. The purpose of this study was to quantify the pre- and post-operative muscular fatty degeneration using a 2-Point Dixon sequence in patients with rotator cuff tears treated by arthroscopic rotator cuff repair. Further, we aim to assess the relationship of preoperative fat fraction values within rotator cuff muscles between patients who experience re-tear and those who do not.

Geon-Ho Jahng¹, Wook Jin¹, Dong-Cheol Woo², Chanhee Lee¹, Chang-Woo Ryu¹, and Dal-Mo Yang^1
1Department of Radiology, Kyung Hee University Hospital at Gangdong, Kyung Hee University, Seoul, Korea, Republic of, ²Biomedical Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul, Korea, Republic of

To assess the ability of proton MR spectroscopy to identify the apparent heterogeneous characteristics of metabolic spectra in effusion regions in human knees using a high-field MRI system, 84 patients with effusion lesions underwent proton MRS with PRESS single-voxel MRS using a clinical 3.0 Tesla MRI system. Nonparametric statistical comparisons were performed to investigate any differences in metabolites among the degenerative osteoarthritis, traumatic diseases, infectious and an inflammatory disease groups. There were no significant differences among the three groups for the CH3 (p=0.9019), CH2 (p=0.6406), and CH=CH lipids (p=0.5467) and water (p=0.2853). 

Saya Horiuchi¹, Taiki Nozaki¹, Atsushi Tasaki², Akira Yamakawa², Yasuhito Kaneko³, Takeshi Hara⁴, Yasuyuki Kurihara¹, and Hiroshi Yoshioka^3
1Radiology, St Luke's International Hospital, Tokyo, Japan, ²Orthopedics, St Luke's International Hospital, Tokyo, Japan, ³Radiological Sciences, University of California, Irvine, Orange, CA, United States, ⁴Department of Intelligent Image Information, Gifu University, Gifu, Japan

The assessment of presurgical rotator cuff muscle fatty degeneration is a main determinant of management in patients with rotator cuff tears. The modified-Goutallier classification has been widely accepted as a qualitative method for evaluation of fatty degeneration in current practice. However, reproducibility is insufficient because it is shown to be highly observer-dependent. The objective of this study was to quantify fatty degeneration of the supraspinatus muscle by using 2-point Dixon technique, and to evaluate the inter- and intra-observer reliability of quantitative analysis of fatty degeneration in comparison with the qualitative modified-Goutallier classification.

Chaoyang Zhang¹, Hu Xianghui², Heather T. Ma², Li Liang², and Chenfei Ye^2
1Harbin Institute of Technology Shenzhen Graduate School, Shenzhen, China, People's Republic of, ²Shenzhen, China, People's Republic of

This study utilized dynamic contrast enhanced (DCE) MRI and blood oxygen level dependent (BOLD) MRI as imaging method, using half quantitative analysis of two kinds of methods to study the relationship between the marrow blood perfusion, oxygen metabolism and bone mineral density. The research found that significant differences were observed in A, MaxEn and Halflife parameters among different BMD groups (p<0.05).In conclusion, different BMD groups has significant difference in perfusion ability on marrow. There is a link between the bone mineral density and marrow blood circulation and metabolism of oxygen. The changed blood circulation may be one of the reasons induced osteoporosis.

Jun Zhao¹, Wei Chen¹, Jian Wang¹, Shuai Li², and Wen-Jing Hou^1
1Radiology, Southwest Hospital, Third Military Medical University, Chongqing, China, People's Republic of, ²MR Collaborations NE Asia, Siemens Healthcare, Beijing, China, People's Republic of

In the past reports, invariably irregularity and high-signal-intensity changes of the free edge of meniscus may lead to a false-positive MR imaging, in addition, MR imaging of the knee invariably missed small meniscal tears, tears and abnormalities of the meniscal free edge, and at times large, unstable tears, result in false-negative. In recent decades, new MR image of water-tissues and collagen-rich tissues, including cartilage, menisci and tendon, has undergone significant progress, which are biological MR image techniques for the characterization tissues .This study was to compare the diagnostic performance of SWI (Susceptibility Weighted Imaging) in the evaluation of meniscal tears at 3T MR with those of a T2 Mapping sequence, using phase value and T2 value as  the quantitative parameters. The phase value was a good predictor to diagnose meniscal tears.

Yasuhito Kaneko^1,2, Taiki Nozaki^1,3, Hon Yu^1,4, Kayleigh Kaneshiro¹, Ran Schwarzkopf⁵, and Hiroshi Yoshioka^1
1Radiological Sciences, University of California, Irvine, Orange, CA, United States, ²Orthopaedic Surgery, Saitama City Hospital, Saitama, Japan, ³Radiology, St. Luke's International Hospital, Tokyo, Japan, ⁴John Tu and Thomas Yuen Center for Functional Onco-Imaging, University of California, Irvine, Orange, CA, United States, ⁵Orthopaedic Surgery, University of California, Irvine, Orange, CA, United States

We assessed patterns of T2 and T1rho value change with Outerbridge grade 1 lesions in OA patients compared to healthy control cartilage utilizing angle and layer dependent approach. T1rho values were more sensitive than T2 values to detect early cartilage degeneration with higher values in OA cartilage than in healthy control. However, T2 and T1rho values in grade 1 cartilage degeneration with signal heterogeneity can be lower compared to those in healthy cartilage.

Shantanu Sinha¹, Vadim Malis², Robert Csapo¹, Jiang Du¹, and Usha Sinha^3
1Radiology, University of California at San Diego, San Diego, CA, United States, ²Physics, University of California at San Diego, San Diego, CA, United States, ³Physics, San Diego State University, San Diego, CA, United States

Acute muscle atrophy is characterized by a loss of muscle mass and muscle force.  Changes are likely to occur in muscle composition, microenvironment, and fiber architecture which could impact muscle function. This study focuses on the changes in these parameters using MR based fat and connective tissue quantification and DTI in a model of acute atrophy induced by Unilateral limb suspension (ULLS).  The % changes in fat and connective tissue were minimal while significant decreases were found in fiber diameter (decrease) and in the pennation angle.  These changes could be primarily responsible for muscle force loss in acute atrophy.

Masayuki Odashima¹, Tsutomu Inaoka¹, Hideyasu Kudo¹, Tomoya Nakatsuka¹, Rumiko Ishikawa¹, Shusuke Kasuya¹, Noriko Kitamura¹, Hiroyuki Nakazawa¹, Koichi Nakagawa², and Hitoshi Terada^1
1Radiology, Toho University Sakura Medical Center, Sakura, Japan, ²Orthopedic Surgery, Toho University Sakura Medical Center, Sakura, Japan

Thin-slice 3D MR imaging of the knee joint using 3D FSE sequence with variable flip-angle refocusing RF pulses may improve the visualization of the three popliteomeniscal fascicles of the lateral meniscus in comparison with conventional 2D MR imaging of the knee joint.

Thomas Lange¹, Benjamin R. Knowles¹, Michael Herbst^1,2, Kaywan Izadpanah³, and Maxim Zaitsev^1
1Department of Radiology, University Medical Center Freiburg, Freiburg, Germany, ²John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States, ³Department of Orthopedic and Trauma Surgery, University Medical Center Freiburg, Freiburg, Germany

Robust T2 mapping of knee cartilage with in situ mechanical loading using prospective motion correction is demonstrated for the patellofemoral and tibiofemoral knee compartments. T2 maps are reconstructed from multiple spin-echo data acquired with slice position updates before every excitation. While T2 maps of the tibiofemoral joint do not show significant changes in response to loading, maps of the patellofemoral joint show a substantial load-induced T2 reduction in the superficial cartilage layers. In particular, the T2 of tangential fibers at the cartilage surface appears to undergo a strong reduction due to a load-induced increase of tissue anisotropy.

Barbara Cervantes¹, Houchun Harry Hu², Amber Pokorney², Dominik Weidlich¹, Hendrik Kooijman³, Ernst Rummeny¹, Axel Haase⁴, Jan S Kirschke⁵, and Dimitrios C Karampinos^1
1Diagnostic and Interventional Radiology, Technische Universität München, Munich, Germany, ²Radiology, Phoenix Children’s Hospital, Phoenix, AZ, United States, ³Philips Healthcare, Hamburg, Germany, ⁴Zentralinstitut für Medizintechnik, Garching, Germany, ⁵Neuroradiology, Technische Universität München, Munich, Germany

High-resolution MRI with 3D turbo spin echo (TSE) is arising as an accurate, non-invasive method for detecting disease and injury in the nerves of the lumbar plexus. Imaging of the lumbar plexus with 3D TSE frequently faces signal contamination of the cerebrospinal fluid (CSF) within the spine. Increasing spatial resolution in 3D TSE can affect flowing signal. The present study describes numerically the effects of the imaging gradients in 3D TSE on flowing CSF and demonstrates in vivo that CSF can be completely suppressed without modifications to refocusing angle modulation when sub-millimeter voxel sizes are used with 3D TSE.

Vladimir Juras^1,2, Laurent Didier³, Vladimir Mlynarik¹, Pavol Szomolanyi¹, Stefan Zbyn¹, Nicole Getzmann³, Joerg Goldhahn³, Stefan Marlovits⁴, and Siegfried Trattnig^1,5
1Department of Biomedical Imaging and Image-Guided Therapy, High Field MR Centre, Medical University of Vienna, Vienna, Austria, ²Department of Imaging Methods, Institute for Measurement Science, Bratislava, Slovakia, ³Novartis Institutes for Biomedical Research, Basel, Switzerland, ⁴Department of Traumatology, Medical University of Vienna, Vienna, Austria, ⁵Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria

An assessment of the reliability of T2 mapping was achieved with a 3D-TESS sequence in patients with cartilage lesions ICRS Grade I-II. Since low-grade cartilage lesions are not usually accompanied by collagen matrix remodeling, we tested the sensitivity of T2 to detect these lesions at 3 and 7T. It seems that the reproducibility of 3T T2 mapping is higher than that of 7T; however, the sensitivity of T2 mapping for the detection of low-grade cartilage lesions was greater at the ultra-high field. T2 mapping could be used in the future as a good alternative to cartilage biopsies in future clinical trials on new therapies aimed at cartilage regeneration.

Masami Yoneyama¹, Nobuyuki Toyonari², Seiichiro Noda², Yukari Horino², Kazuhiro Katahira², and Marc Van Cauteren^3
1Philips Electronics Japan, Tokyo, Japan, ²Kumamoto Chuo Hospital, Kumamoto, Japan, ³Philips Healthcare Asia Pacific, Tokyo, Japan

This study showed a novel non-contrast MR angiography sequence based on gradient echo DIXON sequence with flow-independent relaxation-enhanced method (Relaxation-Enhanced Angiography without Contrast and Triggering: REACT) for evaluating thoracic outlet syndrome. This could provide high-quality MRA with robust fat suppression entire the subclavian area with/without arm abduction.

Daniel J. Park¹, Neal K. Bangerter^2,3, Antony J. R. Palmer¹, Haonan Wang², Bragi Sveinsson⁴, Brian Hargreaves⁴, and Siôn Glyn-Jones^1
1Nuffield Department of Orthopaedics, Rheumotology, and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom, ²Department of Electrical and Computer Engineering, Brigham Young University, Provo, UT, United States, ³Department of Radiology, Univerisity of Utah, Salt Lake City, UT, United States, ⁴Radiology, Stanford University, Stanford, CA, United States

Osteoarthritis, a disease that is a burden to society and individuals, has 3 major stages of progression in cartilage: (1) glycosaminoglycan loss; (2) collagen matrix degeneration; and (3) fissures and volume and thickness loss.  A protocol is proposed to measure the progression of each of these stages of OA at 7 Tesla in about 30 minutes: (1) T1ρ to measure glycosaminoglycan changes; (2) modified DESS measurements of T2 and ADC to measure collagen matrix integrity; and (3) high resolution phase cycled bSSFP images to measure changes in morphology.

Yi-Bin Xi¹, Fan Guo¹, Chun-Li Zhang¹, Hu Xu¹, Long-Biao Cui¹, Chen Li¹, Ping Tian¹, Wei-Guo LI², and Hong Yin^1
1Xijing Hospital, Fourth Mililtary Medical University, Xi'an, China, People's Republic of, ²Bioengineering, University of Illinois at Chicago, Chicago, IL, United States

Magnetization transfer MRI Evaluation of Autologous Chondrocyte Membrane Transplantation in The Knee Joint

Neha KOONJOO^1,2, Clément Tournier³, Aurélien Trotier^1,2, Didier Wecker⁴, William Lefrançois^1,2, Didier Letourneur⁵, Joëlle Amédée Vilamitjana³, Sylvain Miraux^1,2, and Emeline J Ribot^1,2
1CNRS-UMR 5536, Centre de Résonance Magnetique des Systèmes Biologiques, Bordeaux, France, Metropolitan, ²University of Bordeaux, Bordeaux, France, Metropolitan, ³U1026, Bioingénierie Tissulaire (BioTis), Bordeaux, France, Metropolitan, ⁴Bruker Biospin MRI GMBH, Ettlingen, Germany, ⁵INSERM U 1148, Cardiovascular Bio-engineering Laboratory, Paris, France, Metropolitan

In tissue engineering, correct bone regeneration in large bone defects is a major issue. MRI has revealed its high potential to assess continuous tracking of three differently conditioned bone constructs implanted in the rats’ femoral condyles. These constructs aimed at evaluating cumulative effects of hydroxyapatite and/or fucoidan in osteogenesis and vascularization. A water-selective bSSFP sequence with fat suppression and banding artifacts correction was implemented for volumetric measurements. 3D Dynamic-contrast enhanced MRI was applied and pixel-wise analysis resulted in fairly good constructs perfusion evaluation. 3D images spotted distinct volume changes and promising area under curve evolution.

Ioanna Chronaiou^1,2, Ruth Stoklund Thomsen ³, Else-Marie Huuse-Røneid ^2,3, and Beathe Sitter^1
1Department of Radiography, Sør-Trøndelag University College, Trondheim, Norway, ²Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway, ³St Olav's University Hospital, Trondheim, Norway

Psoriatic arthritis (PsA) is a highly heterogeneous inflammatory disease that manifests with inflammation in sacroiliac (SI) joints and spine among other symptoms. PsA patients (N=12) underwent magnetic resonance (MR) imaging examinations to assess the extent of SI joint inflammation. A pixel-based morphometric method for accurate quantification of bone marrow inflammatory edema was compared to SPARCC assessment in MR images of psoriatic arthritis patients with low or very low inflammatory activity. A significant correlation was found, suggesting pixel-based morphometry as a reliable and sensitive quantitative method for measuring inflammation in bone marrow. 

Sameer Khanna^1,2, Nicolas Pannetier¹, Jing Liu¹, and Xiaojuan Li^1
1Radiology, University of California, San Francisco, San Francisco, CA, United States, ²University of California, Berkeley, Berkeley, CA, United States

  There has been a lack of statistical analysis to determine which kinetic model is best suited for analysis of the wrist. This study aims to rectify this by comparing the most commonly used models: Modified Tofts (MT), Two Compartment Uptake (2CU), and Two Compartment Exchange (2CX). Goodness of fit is analyzed by reduced chi squared, while statistical signifance between models is determined by wilcoxon signed-rank.

Andrew S. Nencka¹, Shiv S. Kaushik¹, and Kevin M. Koch^1
1Radiology, Medical College of Wisconsin, Milwaukee, WI, United States

Advanced methods for imaging around metallic implants yield most benefit in the neighborhood around the implant. However, due to the extent of the anatomy in the region of the implant, large field of view acquisitions are often required. In this work, it is shown that a low-resolution acquisition can be used to inform a subsequent reduced field of view acquisition. Significant reductions in the imaged field of view are possible due to the combination of both spatially varying coil sensitivity profiles along with spatially varying resonance frequency bins. Artifact free regions in the neighborhood of the implant are possible with extreme field of view reductions because of the rapid spatial variability of the imaged resonance frequency bins.

Francesca A. A. Leek¹, Anna Therese Sjoholm¹, Christiani Jeyakumar Henry², Xiaodi Su³, Marlena C. Kruger⁴, and John J. Totman^1
1A*STAR-NUS Clinical Imaging Research Centre, Singapore, Singapore, ²A*STAR Clinical Nutrition Research Centre, Singapore, Singapore, ³A*STAR Institute of Materials Research and Engineering, Singapore, Singapore, ⁴School of Food and Nutrition, College of Health, Massey University, Palmerston North, New Zealand

The feasibility of utilising proximal femur cortical bone quality as a biomarker for diabetes risk in post-menopausal Chinese-Singaporean women was investigated. Non-dominant proximal femurs were imaged with quantitative CT (QCT) and MR for the assessment of volumetric bone mineral density (vBMD) and cortical bone porosity. A significant (p<0.01; n=8) positive correlation between MRI vBMD and QCT vBMD for the region of maximum cortical thickness was shown. Whether MRI vBMD is associated with fracture risk and if it is sensitive to changes due to dietary or drug intervention needs to be investigated to fully assess the clinical potential of this method.

Maria Kalimeri¹, Christiani Jeyakumar Henry², Xiao Di Su³, Marlena C. Kruger⁴, and John J. Totman^1
1A*STAR-NUS Clinical Imaging Research Centre, Singapore, Singapore, ²Clinical Nutrition Research Centre, Singapore, Singapore, ³Institute of Materials Research and Engineering, Singapore, Singapore, ⁴School of Food and Nutrition, College of Health, Massey University, Palmerston North, New Zealand

Osteoporosis is a skeletal disorder that affects predominantly postmenopausal women. The screening method for osteoporosis is Dual X-ray Absorptiometry (DXA), which has several limitations, including the inability to differentiate between trabecular and cortical bone. 3D imaging modalities can give information about each bone component, which contribute to bone strength in different ways. MRI is an attractive alternative due to lack of ionising radiation. In this abstract, we present a method for bone density assessment of trabecular bone in the proximal femur using MRI. Strong correlations with both DXA and Quantitative Computed Tomography (QCT) measurements of similar regions were observed.  

Daehyun Yoon¹, Kathryn Stevens¹, and Brian Hargreaves^1
1Radiology, Stanford University, Palo Alto, CA, United States

T2-weighted MRI is essential to detect neural compression in the lumbar spine after spinal fusion surgery in patients with recurrent radicular symptoms. Unfortunately, off-resonance artifacts induced from lumbar fusion devices make the conventional T2-weighted MR images extremely challenging or impossible to interpret. We present a modified version of MAVRIC-SL, an MR sequence designed to correct for metal-induced artifacts, to allow T2 contrast, significantly improving diagnostic capabilities in the postoperative lumbar spine.

Akio Hiwatashi¹, Osamu Togao¹, Koji Yamashita¹, Kazufumi Kikuchi¹, Masami Yoneyama², and Hiroshi Honda^1
1Clinical Radiology, Kyushu University, Fukuoka, Japan, ²Philips Electronics Japan, Tokyo, Japan

MR neurography (MRN) is a useful technique with which to evaluate abnormal conditions of the peripheral nerves such as chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). We have developed a new simultaneous T2 mapping and MRN method called SHINKEI Quant. Patients with CIDP could be distinguished from normal subjects in size and T2 value of the peripheral nerves with SHINKEI Quant.

Na Chai¹, Panli Zuo², Stephan Kannengiesser³, Andre De Oliveira³, Shun Qi¹, and Hong Yin^1
1Department of Radiology, Xijing Hospital, Xi'an, China, People's Republic of, ²Siemens Healthcare, MR Collaborations NE Asia, Beijing, China, People's Republic of, ³Application Predevelopment, Siemens Healthcare, Erlangen, Germany

Using the multi-echo ¹H-MRS and multi-echo Dixon VIBE, we measured the proton density fat fraction (PDFF) using MR imaging in the bone marrow of L2-L4 vertebra, and compared with the bone mineral density (BMD) measured using computed tomography (CT). The resutls showed a significant correlation between PDFF measured using the two methods, and also PDFF with BMD.

Tamami Shirakawa¹, Kazutoshi Inamura², Yasuhisa Tanaka³, Takeshi Hoshikawa³, Megumi Kuchiki¹, and Atsuko Oda^1
1Radiology, Tohoku Central Hospital, Yamagata, Japan, ²Otolaryngology, Tohoku Central Hospital, Yamagata, Japan, ³Orthopaedic Surgery, Tohoku Central Hospital, Yamagata, Japan

Calcific longus colli tendinitis is an inflammatory lesion in the prevertebral space. When prevertebral effusion is observed on MRI, awareness of the prevertebral muscle swelling with signal change and the associated mass effect would suggest that the main site of the lesion is the prevertebral space, not the retropharyngeal space and may thus prevent both misdiagnosis as a retropharyngeal abscess and unnecessary treatment. The variability in the level of calcification and prevertebral effusion is highlighted in the present study in order to assist in the establishment of the correct radiological diagnosis.

Kevin Tschiesche¹, Alexander Gussew¹, Christian Hein², and Jürgen Rainer Reichenbach^1
1Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany, ²Ganshorn Medizin Electronic GmbH, Niederlauer, Germany

The aim of this work was the implementation of combined spirometric and ³¹P MRS measurements. We adapted a commercial gas exchange system by extending the gas sampling line from 3 m to 5 m to perform acquisitions of pulmonary ventilation in a MR scanner. Calibration measurements showed changes in an appropriate range in the delay- and response time.

David J Kahn¹, Daniel Mittelstaedt¹, and Yang Xia^1
1Physics and Center for Biomedical Research, Oakland University, Rochester, MI, United States

High-resolution T2 imaging of AC is able to quantitatively measure depth-dependent features of articular cartilage (AC). When the cartilage articular surface (AS) is oriented normal (0°) to the external magnetic field, healthy AC takes on a laminar appearance that indicates the superficial zone (SZ), transitional zone (TZ), and radial zone (RZ), where collagen fibers are oriented parallel, random, and perpendicular to the AS [1]. When the AS is oriented at the magic angle (55°), the nuclear dipolar interaction is minimized and the tissue appears homogeneous. Compression of AC has effects that change many zonal properties [2,3], and hypertrophy may alter the biomechanical function and depth-dependent collagen ultra-structure of AC.

JAE MO PARK¹, Sonal Josan¹, Dirk Mayer², Ralph E Hurd³, Youngran Chung⁴, David Bendahan⁵, Daniel M Spielman¹, and Thomas Jue^4
1Radiology, Stanford University, Stanford, CA, United States, ²Diagnostic Radiology and Nuclear Medicine, University of Maryland, Baltimore, MD, United States, ³Applied Sciences Laboratory, GE Healthcare, Menlo Park, CA, United States, ⁴Biochemistry and Molecular Medicine, University of California - Davis, Davis, CA, United States, ⁵Centre de Resonance Magnetique Biologique et Medicale, Aix-Marseille University, Marseille, France

The present study reports the use of hyperpolarized [1-¹³C]lactate and [2-¹³C]pyruvate to measure the rapid pyruvate and lactate kinetics in rat skeletal muscle. The results provide support for a critical underpinning of both the glycogen shunt model and the intracellular lactate shuttle hypothesis, and cautions against an overly simplistic view of glycolytic end products as merely hypoxia biomarkers.

Mikaël Simard¹, Emily J. McWalter², Garry E. Gold², and Ives R. Levesque^1,3
1Medical Physics, McGill University, Montreal, QC, Canada, ²Radiology, Stanford University, Stanford, CA, United States, ³Research Institute of the McGill University Health Centre, Montreal, QC, Canada

Quantitative magnetization transfer (QMT) probes macromolecular content in tissue and may be a useful tool in the early detection of meniscal degeneration. QMT mapping of the meniscus was performed in 3 cadaver knee specimens in situ, and repeated ex situ following dissection and immersion in perflubron. After extraction, a decrease in the restricted pool fraction f was noted, while T1obs and T1f increased. A trend towards lower values of the exchange rate kf was noted after excision. T2 and T2r were relatively constant. The variation in QMT parameters may be caused by the diffusion of perflubron into the ex situ samples.

Yajun Ma¹, Hongda Shao¹, Michael Carl², Eric Chang¹, and Jiang Du^1
1Department of Radiology, UCSD, San Diego, CA, United States, ²Global MR Application & Workflow, General Electric, San Diego, CA, United States

Magnetic resonance imaging biomarkers such as T₂ and T_1rho have been widely used in the evaluation of osteoarthritis (OA). The principal confounding factor for T₂ and T_1rho measures is the magic angle effect, which may result in a several fold increase in T₂ and T_1rho values when the fibers are oriented near 55° (the magic angle) relative to the B0 field. This often far exceeds the changes produced by OA, and may make definitive interpretation of elevated T_1rho and T₂ values difficult or impossible. Magic angle independent MR biomarkers are highly desirable for more accurate assessment of OA. In this study we report the use of two-dimensional ultrashort echo time magnetization transfer (UTE-MT) imaging and modeling for magic angle independent assessment of the tissue properties.

James F Griffith¹, Teresa M Hu², David KW Yeung¹, D F Wang¹, Fan Xiao¹, and Brian Tomlinson^2
1Imaging and Interventional Radiology, The Chinese University of Hong Kong, Hong Kong SAR, Hong Kong, ²Medicine, The Chinese University of Hong Kong, Hong Kong SAR, Hong Kong

Achilles tendon xanthoma is a key clinical indicator of familial hypercholesteraemia (FH) and associated cardiovascular disease. Treatment that reduces the size of tendon xanthoma also benefits the arterial manifestations of FH. Ultrasound and MRI are often used to detect and monitor treatment response of tendon xanthomas using parameters such as tendon thickness, width and cross-sectional area. However, MR-based parameters derived from the DIXON technique to determine tendon volume and intratendinous percentage fat fraction may be more sensitive than traditional US and conventional MRI.

Mingming Lu¹, Peng Peng¹, Yu Zhang², and Fei Yuan^1
1Affiliated Hospital of Logistics University of Chinese People's Armed Police Forces, Tianjin, China, People's Republic of, ²Philips Healthcare, Beijing, China, People's Republic of

This study aimed to investigate the efficacy of MRI for evaluating morphology and long-term prognosis of acetabulum in pediatric patients with DDH. The bony acetabular index (BAI), cartilaginous acetabular index (CAI), acetabular anteversion index of bone (BAAV) and cartilage (CAAV) were measured and cartilaginous index (CI=(BAI-CAI) / BAI) was computed. There was obvious differences with statistical significance in the CI between non-reduced group and reduced group (t=-2.315, P=0.24), and age was also negatively correlated with the CI (r = -0.345, P =0.01) . The CI can preliminarily predict the long-term prognosis of DDH after reduction.

Bimin Chen^1,2, Hongda Shao¹, Michael Carl³, Arthur Kavanaugh⁴, Graeme M Bydder¹, and Jiang Du^1
1Radiology Department, UCSD, San Diego, CA, United States, ²Radiology Department, The first affiliated hospital of Jinan University, Guangzhou, China, People's Republic of, ³GE Healthcare, San Diego, CA, United States, ⁴Center for Innovative Therapy Division of Rheumatology, Allergy, and Immunology, UCSD, San Diego, CA, United States

Achilles tendon enthesitis is the source of the the heel pain of PsA patients. The current measures based on pressure being placed on various entheses during physical examination are both insensitive and non-specific.Also it’s very time consuming and poorly reproducible.MR imaging with ultrashort echo time (UTE) sequences provides a good option for assessing entheses, which has a relatively short T2 and largely “invisible” with clinical MR sequence.

Ivan P.W. Teng¹, Jamie X.M. Ho¹, Trina Kok¹, Philip Lee², Melvin K.S. Leow³, Hong Chang Tan⁴, Chin Meng Khoo⁵, George K Radda⁶, and Mary C Stephenson^1,5
1Clinical Imaging Research Centre, A*STAR-NUS, Singapore, Singapore, ²SBIC, A*STAR, Singapore, Singapore, ³SICS, A*STAR, Singapore, Singapore, ⁴Department of Endocrinology, SGH, Singapore, Singapore, ⁵Department of Medicine, NUS, Singapore, Singapore, ⁶Biomedical Research Council, A*STAR, Singapore, Singapore

Previous studies have indicated differences in insulin sensitivity between lean Indian and Chinese men. In this study we used ³¹P MRS and a dorsiflexion task to assess muscle mitochondrial function, thought to be associated with insulin sensitivity, via PCr recovery rates. No inter-ethnic group differences were observed in measured blood parameters (HbA1c, fasting blood glucose level and M-value) between groups. However, positive correlations were observed between τPCr and both HbA1c and fasting blood glucose levels suggesting poorer mitochondrial function. No correlation was observed with M-value. Larger sampling sizes are necessary for these correlations and group differences to reach statistically-significant conclusions.

Jiao WANG¹, Yun fei ZHA¹, Dong XING¹, Lei HU¹, Chang sheng LIU¹, Hui LIN², and Yuan LIN^1
1Department of Radiology,Renmin Hospital of Wuhan University ,Wuhan 430060,China, Wu han, China, People's Republic of, ²GE Healthcare China, Shanghai 200000,China, Shang hai, China, People's Republic of

To explore the relationship between the vertebra subchondral bone (VSB), the cartilage endplate (CEP) perfusion with intervertebral disc degeneration (IVDD). 18 individuals underwent lumbar conventional and DCE-MRI. The cranial and caudal VSB and CEP perfusion parameters (K^trans, K_ep, V_e) were measured. The VSB perfusion parameters K_^ep of Pfirrmann I and II, Pfirrmann I and IV, Pfirrmann III and IV,the cranial CEP K_ep of Pfirrmann III and II showed significant difference. In the early progress of IVDD, its metabolism increase compensatory, clinical research should put more emphasis on early onset stage of IVDD such as in Pfirrmann II.

Ningning Zhang¹, Yanqiu Lv¹, Kaining Shi², Di Hu¹, Huiying Kang¹, Yue Liu¹, Runhui Wu³, and Yun Peng^1
1Imaging Center, Beijing Children's Hospital, Capital Medical University, Beijing, China, People's Republic of, ²Imaging System Clinical Science, Philips Healthcare, Beijing, China, People's Republic of, ³Hematology Center, Beijing Children's Hospital, Capital Medical University, Beijing, China, People's Republic of

T2 mapping sequences can help detect changes in the water and collagen content. This sequence have been used extensively in osteoarthritis research studies to detect disease and treatment related changes in articular cartilage(1-3). However, little is known about the early cartilage changes in hemophilia patients, and once established, arthropathy follows a progressive and non-reversible process despite the use of factor concentrates.

Uran Ferizi¹, Ignacio Rossi², Oran Kennedy², Thorsten Kirsch², Jenny Bencardino¹, and Jose Raya^1
1Department of Radiology, New York University School of Medicine, New York, NY, United States, ²Orthopaedic Surgery, New York University School of Medicine, New York, NY, United States

The development of novel treatment strategies that would prevent joint replacement surgery at young age, as a result of PTOA, is critical. Hours after non-contact rupture of the anterior cruciate ligament, high concentrations of PG and type II collagen fragments are found in the synovial fluid. DTI has emerged as an imaging biomarker that can assess both PG content and collagen architecture with greater accuracy than T2 or Na imaging. The current interpretation of DTI measurements is that changes in the level of proteoglycans (PG) affect the mean diffusivity (MD) index from the DTI, while the collagen structure affects the fractional anisotropy (FA). 
This study examines the feasibility of DTI, by using biomechanics for simulating a controlled cartilage damage. We find that DTI metrics are sensitive to the early changes in the cartilage as a result of injury. Specifically, the correlations of the mean diffusivity (MD) are statistically significant, but those of fractional anisotropy (FA) are not. The additional validation with histology, as well as a clinical scanning environment make these results important in the translation of DTI to clinical practice.

Noam Ben-Eliezer^1,2, Akio Ernesto Yoshimoto², KAI Tobias Block^1,2, Roy Davidovitch³, Thomas Youm³, Robert Meislin³, Michael Recht^1,2, Daniel K Sodickson^1,2, and Riccardo Lattanzi^1,2
1Center for Advanced Imaging Innovation and Research (CAI2R), New York University School of Medicine, New York, NY, United States, ²Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, United States, ³Department of Orthopedic Surgery, New York University Hospital for Joint Diseases, New York, NY, United States

Early diagnosis of cartilage defects is critical for the success of corrective surgical procedures in patients with femoroacetabular impingement (FAI). T₂ is a biomarker for early biochemical degeneration of cartilage, but in vivo T₂ mapping is challenging while commonly used techniques based on exponential fit of multi spin-echo protocols are inaccurate. We used a Bloch simulation based T₂ mapping technique – the EMC algorithm – to retrospectively quantify reliable T₂ values in the hip cartilage of FAI patients. We then defined a normalized T₂-index using an internal reference and showed that it allows detection of surgically confirmed cartilage lesions with 95% accuracy.

Victor Casula^1,2, Mikko J. Nissi^3,4, Jana Podlipská^1,5, Marianne Haapea^6,7, Simo Saarakkala^1,2,7, Ali Guermazi⁸, Eveliina Lammentausta^2,7, and Miika T. Nieminen^1,2,7
1Research Unit of Medical Imaging, Physics and Technology, University of Oulu, Oulu, Finland, ²Medical Research Center, University of Oulu and Oulu University Hospital, Oulu, Finland, ³Department of Applied Physics, University of Eastern Finland, Kuopio, Finland, ⁴Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland, ⁵Infotech Oulu, University of Oulu, Oulu, Finland, ⁶Department of Psychiatry, Oulu University Hospital, Oulu, Finland, ⁷Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland, ⁸Department of Radiology, Boston University School of Medicine, Boston, MA, United States

Adiabatic $$$T_{1\rho}$$$, adiabatic $$$T_{2\rho}$$$ and $$$T_2$$$ of articular cartilage (AC) were compared between patients with pre- or early radiographic knee osteoarthritis (OA) (KL=1,2) and volunteers. Further comparisons were performed after classifying the subjects according to different signs of OA, including symptoms and functional impairment assessed by the Western Ontario and McMaster Universities questionnaire (WOMAC) and presence of structural changes assessed by MRI OA Knee Score (MOAKS). Increased adiabatic $$$T_{1\rho}$$$ and $$$T_{2\rho}$$$ were significantly associated with clinical signs of OA. The findings suggest that novel rotating frame of reference techniques have considerable potential for in vivo OA research and clinical use.  

Ryan Breighner¹, Sonja Eagle¹, Gaspar Delso², Hollis G. Potter¹, and Matthew F. Koff^1
1Department of Radiology and Imaging - MRI, Hospital for Special Surgery, New York, NY, United States, ²General Electric Healthcare, Zurich, Switzerland

Standard magnetic resonance imaging protocols fail to generate sufficient positive contrast for the direct imaging of bone. This study demonstrates the use of zero echo time (ZTE) imaging of the appendicular skeleton. Knee, shoulder, ankle, and wrist joints were imaged and scan parameters were varied between subjects to optimize acquisition of joints of interest. ZTE images permitted the visualization of fine tendinous structures in addition to bone. ZTE may prove useful when concurrent imaging of tendon and bone is required or when bone imaging is necessary but radiation dose is undesirable, due to patient age or anatomy. 

Zhijun Li¹, Prasanna Karunanayaka¹, Matthew Muller², Christopher Sica¹, Jian-Li Wang¹, Lawrence Sinoway², and Qing X. Yang^1,3
1Center for NMR Research, Department of Radiology, College of Medicine, The Pennsylvania State University, Hershey, PA, United States, ²Heart and Vascular Institute, College of Medicine, The Pennsylvania State University, Hershey, PA, United States, ³Department of Neurosurgery, College of Medicine, The Pennsylvania State University, Hershey, PA, United States

Unlike in human brain imaging, normalization to a common template during exercising is a difficult proposition in muscle-imaging studies. Still, motion artifact has been an issue for dynamic analysis of exercise paradigm. We used individual Independent Component Analysis (ICA) to identify the “motion component” during exercise (rhythmic plantar-flexion) and anatomical and temporal features of BOLD signal. We simultaneously identified the lower leg muscle groups and their common hemodynamic behaviors under a low-level exercise paradigm and revealed an intriguing hemodynamic respond characteristic with a prominent transient increase and followed by a negative BOLD signal sustained to the end of exercise.

Ariel C. Zane¹, Donnie Cameron¹, Seongjin Choi¹, David A. Reiter², Kenneth W. Fishbein², Christopher M. Bergeron¹, Eleanor Simonsick¹, Richard G. Spencer², and Luigi Ferrucci^3
1Translational Gerontology Branch, NIH/National Institute on Aging, Baltimore, MD, United States, ²Laboratory of Clinical Investigation, NIH/National Institute on Aging, Baltimore, MD, United States, ³Intramural Research Program, NIH/National Institute on Aging, Baltimore, MD, United States

We examined the effect of high intensity physical activity on the post-exercise PCr recovery rate (k_PCr), testing whether the decline in muscle quality may be attributed to an age-related decline in muscle mitochondrial capacity. In-vivo ³¹P MRS measurements were obtained before, during, and after a rapid knee-extension exercise. The cross-sectional results in the BLSA show that both age and frequency of physical activity are significant predictors of k_PCr. However, neither is significantly correlated with a strength-based assessment of muscle quality.

Martin Schwartz^1,2, Günter Steidle¹, Petros Martirosian¹, Ander Ramos-Murguialday³, Bin Yang², and Fritz Schick^1
1Section on Experimental Radiology, Department of Radiology, University of Tuebingen, Tuebingen, Germany, ²Institute of Signal Processing and System Theory, University of Stuttgart, Stuttgart, Germany, ³Institute for Medical Psychology and Behavioural Neurobiology, University of Tuebingen, Tuebingen, Germany

Diffusion-weighted images of the lower leg have shown to be impaired by signal voids in different muscle groups with unknown underlying physiological processes. For more detailed insight into this topic, simultaneous surface electromyography measurements of the electrical activity of muscles during the MR scan were recorded. A classification of the appeared signal voids in the diffusion-weighted images based on initial findings in the EMG measurements is demonstrated.

Fei Gao¹, Chengyan Wang², Rui Zhang¹, Xiaodong Zhang³, Kai Zhao³, Jue Zhang^1,2, Xiaoying Wang^2,3, and Jing Fang^1,2
1College of Engineering, Peking University, Beijing, China, People's Republic of, ²Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, People's Republic of, ³Department of Radiology, Peking University First Hospital, Beijing, China, People's Republic of

In this study, a multi-shot ASE sequence with 32 varied echo shifts was implemented  to acquire the source images for foot muscle OEF quantification. Three healthy volunteers (mean age 23 ± 1 years, range 22-24) were recruited to undergo the imaging of the foot using a 3.0-T whole-body scanner. The OEF and R2' maps indicate the feasibility of the proposed multi-shot ASE sequence in quantifying foot muscle OEF. These results hold promise for some clinical uses, for example, to study vascular function in peripheral artery disease.

CY Wang¹, L Jiang², R Zhang³, XD Zhang⁴, H Wang², K Zhao⁴, LX Jin², J Zhang^1,3, XY Wang^1,4, and J Fang^1,3
1Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, People's Republic of, ²Philips Healthcare, Suzhou, China, People's Republic of, ³College of Engineering, Peking University, Beijing, China, People's Republic of, ⁴Department of Radiology, Peking University First Hospital, Beijing, China, People's Republic of

Recently, MRI based methods for measuring muscle oxygen extraction fraction (OEF) have been reported. Asymmetric spin-echo (ASE) sequence combining with a susceptibility model is the most widely used approach. However, conventional ASE sequence uses single-shot (SS) EPI for data acquisition, which suffers from the problem of severe susceptibility artifacts and distortion due to the relatively long echo train length (ETL). One solution is to employ multi-shot (MS) EPI instead of SS EPI for data acquisition. With the use of MS-ASE technique, much higher spatial resolution could be achieved for lower extremity muscle imaging.

Nick Zafeiropoulos¹, Valeria Ricotti², Matthew Evans^1,3, Jasper Morrow³, Paul Matthews⁴, Robert Janiczek⁵, Tarek Yousry^1,3, Christopher Sinclair^1,3, Francesco Muntoni², and John Thornton^1,3
1Neuroradiological Academic Unit, UCL Institute of Neurology, London, United Kingdom, ²Dubowitz Neuromuscular Centre, UCL Institute of Child Health, London, United Kingdom, ³MRC Centre for Neuromuscular Diseases, London, United Kingdom, ⁴Imperial College London, London, United Kingdom, ⁵GlaxoSmithKline, London, United Kingdom

A simplified CPMG signal decay model was used to determine muscle-water T2 (T2m) in fat-infiltrated skeletal muscle, using a predetermined mono-exponential approximation to the fat decay component. This approach enabled the stable estimation of T2m in the forearm muscles of non-ambulant Duchenne muscular dystrophy patients and healthy controls from a multi-echo CPMG acquisition with only 12 echo-times. Values obtained were in good agreement with previous reports, and largely independent of muscle fat content.

Wen-Jing Hou¹, Pan-Li Zuo², Esther Meyer³, Jun Zhao¹, and Wei Chen^1
1Radiology, Southwest Hospital, Third Military Medical University, Chongqing, China, People's Republic of, ²Siemens Healthcare, MR Collaboration NE Asia, Beijing, China, People's Republic of, ³Siemens Healthcare, Erlangen, Germany

Quantitative cartilage morphometry on MR images is a valuable tool to reveal changes of cartilage in pathological knees. In this study, we used an automated cartilage segmentation software to quantifying the cartilage loss in osteoarthritis patients, meniscus tears patients and compared with the control healthy subjects. The aim of this study was to examine whether there is dominant cartilage which has the most loss in cartilage volume in osteoarthritis and meniscus tears. The outcome is that using the precise quantification of cartilage change in percentage is valuable to specify the most venerable cartilage in pathological knees.

Constantinos Anastasopoulos^1,2, Melissa Hooijmans¹, Jedrek Burakiewicz¹, Andrew G. Webb¹, Janbernd Kirschner², Jan J.G.M. Verschuuren³, Erik H. Niks³, and Hermien E. Kan^1
1Gorter Center, Leiden University Medical Center, Leiden, Netherlands, ²Pediatric Neurology and Muscle Disorders, University Clinic Freiburg, Freiburg, Germany, ³Department of Neurology, Leiden University Medical Center, Leiden, Netherlands

The interpretation of muscle T2 relaxation times in muscular dystrophies is complicated by the disease progression, as both inflammation and increased fat content result in a longer T2. We measured water-T2 in two muscles of the lower leg using a tri-exponential fitting of the T2 decay in patients with DMD and healthy controls. We found a significantly higher T2-heterogeneity in the soleus muscle of patients, with no significant difference between the two groups in average T2 values. T2-heterogeneity should be taken into consideration when using the water T2 of the diseased muscle as an outcome measure for therapeutic interventions.

Yong Zhang¹, Aihong Yu¹, Yu Zhang², Chao Wang³, Yangyang Duan Mu¹, Chenxin Zhang¹, Zhuang Zhou⁴, Wei Zhao¹, Ling Wang¹, and Xiaoguang Cheng^1
1radiology, Beijing Jishuitan hospital, Beijing, China, People's Republic of, ²radiology, Philips Healthcare, Beijing, China, Beijing, China, People's Republic of, ³Beijing Institute of Traumatology and Orthopedics, Beijing, China, People's Republic of, ⁴Orthopedics, The Third Hospital of Hebei Medical University, Beijing, China, People's Republic of

This study aimed to evaluate the reliability of fat content measurement of lumbar vertebrae marrow and lumbar paraspinal muscle using an multi-echo 3D DIXON method. A total of 31 volunteers (15 males and 16 females) were included in this study and underwent liver mDIXON-quant MR imaging by an radiologist and this examinations were repeated by another radiologist within 2 weeks. The radiologists measured fat content of L3, psoas (PS), erector spinae (ES), and multifidus (MF) muscles on the central L3 axial MR images on ISP V7 workstation and after 2 weeks they repeated the same measurements. Our results showed mean fat content of L3, PS, ES, MF was 38.19%, 3.52%, 3.48%, 3.53% for males and 32.11%, 3.40%, 7.06%, 7.14% for females. The repeatability and reproducibility of measurement of fat content, T2* and R2* of L3, PS, ES, MF was high (the intra-observer ICC and inter-observer ICC all>0.9). Fat content measurement of lumbar vertebrae marrow and lumbar paraspinal muscle using mDIXON-quant imaging has high reliability and be potentially used in clinical practice.

Rajakumar Nagarajan¹, Zohaib Iqbal¹, Manoj K Sarma¹, S. Sendhil Velan², and M.Albert Thomas^1
1Radiological Sciences, University of California Los Angeles, Los Angeles, CA, United States, ²Laboratory of Molecular Imaging, Singapore Bioimaging Consortium, Singapore, Singapore

Skeletal muscle plays a major role in the development of insulin resistance (IR) and progression to type 2 diabetes.  A recent work has used long TE (350ms) based PRESS localized spectrum in the vastus lateralis region of thigh muscle without any exercise to investigate acetylcarnitine, a compound formed when acetyl-Coenzyme A exceeds use by the tricarboxylic cycle in the mitochondria. This work focused on examining regional variations of acetylcarnitine in the thigh and calf muscles using the long TE MRS. Our preliminary results show the unequivocal presence of acetylcarnitine in lean, young healthy thigh muscle regions and decreased level in one diabetic type 2 patient. 

Kevin M Koch¹, Matthew F Koff², Parina Shah², S S Kaushik¹, Andrew Nencka¹, and Hollis G Potter^2
1Radiology, Medical College of Wisconsin, Milwaukee, WI, United States, ²Magnetic Resonance Imaging, Hospital for Special Surgery, New York, NY, United States

The failure of hip arthroplasty may be attributed to metallic or polyethylene debris generated from implant components.  The metallic components, and their associated debris are composed of cobalt-chromium alloys, which have a strong paramagnetic magnetic susceptibility relative to biological materials.  Previously, we demonstrated a mechanism to utilize MRI data to qualitatively highlight cobalt-chromium debris deposits in vivo.  In the current study, we extend this work to provide a quantifiable regional metallosis metric.  In addition, this regional quantitative metric is shown to statistically correlate with local histology metallosis scores in subjects undergoing total hip revision surgery.     

Kevin M Koch¹ and S S Kaushik^1
1Radiology, Medical College of Wisconsin, Milwaukee, WI, United States

Slab selection is a crucial component of 3D-MSI metal artifact reduction sequences, due to the need to reduce phase-encoded fields of view for body imaging applications in the hip, spine, and shoulder.  However, existing commercial 3D-MSI sequences are prone to signal loss at the edges of prescribed slabs.  Here, we explain the source of this signal loss and demonstrate a calibration algorithm that can be used to reduce this slab-boundary signal loss in 3D-MSI. The presented methods are demonstrated on a calibrated 3D-MSI total hip replacement dataset acquired at 1.5T.  

Maggie Mei Kei Fung¹, Ek Tsoon Tan², David Soon Yiew Sia³, and Darryl Sneag^3
1MR Apps & Workflow, GE Healthcare, New York, NY, United States, ²MR, GE Global Research Center, Niskayuna, NY, United States, ³MRI Research Lab, Hospital of Special Surgery, New York, NY, United States

Diffusion tensor imaging (DTI) can potentially be helpful in visualizing peripheral nerves and assessing nerve damages. However, upper extremity DTIs (wrist, elbows & arm) are susceptible to distortion and fat suppression failure, especially in arms-down position where the area of interest is far from iso-center and can have more B0 inhomogeneity. In this study, we aim to investigate whether a combination of B0 correction methods can help reduce fat suppression failure, improve spatial misalignment and thus improve nerve tracking. We observed consistent fat suppression improvement at the wrist, but no significant improvement in spatial accuracy.

Caron Parsons^1,2, Charles Hutchinson^1,2, Emma Helm², Alexander Kenneth Clarke³, Asfand Baig Mirza³, Qiang Zhang⁴, and Abhir Bhalerao^4
1Division of Health Sciences, University of Warwick, Coventry, United Kingdom, ²Department of Radiology, University Hospital Coventry & Warwickshire, Coventry, United Kingdom, ³Warwick Medical School, Coventry, United Kingdom, ⁴Department of Computer Sciences, University of Warwick, Coventry, United Kingdom

There are multiple methods available for skeletal age determination in the paediatric endocrine population. Only two methods, using left hand and wrist x-rays are in frequent clinical use, however Greulich & Pyle is based on data collated between 1931 and 1942 and Tanner Whitehouse uses data from as far back as 1949. We present the initial results of an automated software model of shape and textural analysis of the physes of the knee. 

Cem M Deniz^1,2, Greg Chang³, and Ryan Brown^1
1Department of Radiology, Center for Advanced Imaging Innovation and Research (CAI2R) and Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, NY, United States, ²The Sackler Institute of Graduate Biomedical Sciences, New York University School of Medicine, New York, NY, United States, ³Department of Radiology, Center for Musculoskeletal Care, New York University Langone Medical Center, New York, NY, United States

Phantoms have been used in MRI for sequence optimization and scanner calibrations. Recent developments in 3D printing technology have provided tools to manufacture application specific phantoms in a fast and reliable way. In this work, we used 3D printing technology to build a resolution phantom for optimization of trabecular bone structure imaging. We used rods with different thickness, orientation and spacing for capturing the range of possible trabecular bone structures. Developed phantom was used to investigate the effect of slice thickness on trabecular bone structure imaging.  

Daehyun Yoon¹, Sandip Biswal¹, Brian Rutt¹, Amelie Lutz¹, and Brian Hargreaves^1
1Radiology, Stanford University, Palo Alto, CA, United States

For the past few decades, MRI has been increasingly used for identifying peripheral nerve injury, causing chronic and neuropathic pain. Unfortunately, a substantial number of MRI examinations fails to find the causative nerve damage, possibly because it is too subtle or small. Recent developments of PET-MRI demonstrated improved detection capability of the nerve damage, but the precise anatomic characterization of the detected lesion still remains challenging. We introduce high-resolution 3D steady-state imaging sequences at 7T that enable examination of microstructures of peripheral nerves in extremities. We believe our methods have great potential for improving diagnosis of various pain syndromes.

Dominik Nörenberg^1,2, Marco Armbruster¹, Yi-Na Bender², Thula Walter², Gerd Diederichs², Bernd Hamm², Ben Ockert³, and Marcus R. Makowski^2,4
1Department of Clinical Radiology, Munich University Hospitals Campus Großhadern, Germany, Munich, Germany, ²Department of Radiology, Charité, Berlin, Germany, Berlin, Germany, ³Department of Trauma and Orthopedic Surgery, Shoulder and Elbow Service, Munich University Hospitals Campus Großhadern, German, Munich, Germany, ⁴King’s College London, Division of Imaging Sciences and Biomedical Engineering, London, United Kingdom, London, United Kingdom

Shoulder pain is regarded as the second most common musculoskeletal disorder in the general population. 44 % of shoulder pain syndromes are related to subacromial shoulder impingement (SAIS) due to rotator cuff tear (RCT) and glenohumeral joint arthritis. Especially subacromial spur formation is associated with SAIS and RCT. Our study demonstrates that SWMRI allows for a reliable detection and precise 3D-localization of subacromial spur formation under the coracoacromial arch in patients with SAIS and provides superior evaluation of diamagnetic spur formation compared to standard shoulder MRI using conventional radiography as a reference.

Damien Nguyen^1,2, Tom Hilbert^3,4,5, Jean-Philippe Thiran^5,6, Tobias Kober^3,4,5, and Oliver Bieri^1,2
1Radiological Physics, Dep. of Radiology, University of Basel Hospital, Basel, Switzerland, ²Department of Biomedical Engineering, University of Basel, Basel, Switzerland, ³Advanced Clinical Imaging Technology (HC CMEA SUI DI BM PI), Siemens Healthcare AG, Lausanne, Switzerland, ⁴Department of Radiology, University Hospital (CHUV), Lausanne, Switzerland, ⁵LTS5, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, ⁶Department of Radiology, University Hospital Lausanne (CHUV), Lausanne, Switzerland

In this study, we explore the possibility of using a highly undersampled 3D phase-cycled balanced Steady-State Free-Precession (bSSFP) sequence (trueCISS) to image metal implants in the body and compare it to the Slice Encoding for Metal Artifact Correction (SEMAC) method. We show that the trueCISS approach not only offers qualitatively good morphological images, but also delivers quantitative maps that could potentially improve the overall diagnostic quality and efficiency within a clinically reasonable time.

Yimin Ma¹, Panli Zuo², Mathias Nittka³, and Xiaoguang Cheng^4
1Department of radiology, Department of radiology, Jishuitan Hospital, Beijing, China, Beijing, China, China, People's Republic of, ²Siemens Healthcare, MR Collaborations NE Asia, Beijing, China, Beijing, China, China, People's Republic of, ³Siemens Healthcare, Erlangen, Germany, Erlangen, Germany, ⁴Department of Radiology, Department of Radiology, Jishuitan Hospital, Beijing, China, Beijing, China, China, People's Republic of

With the rapid development of medicine technology, total hip arthroplasty (THA) is now widely used in the treatment of endstage hip osteoarthritis, severe hip fracture, hip bone tumor, and so forth. THA can relieve hip pain and improve the activity of the joints, while it still brings some unexpected complications, such as periprothesis bone resorption, periprothesis fractures, and metallic implants dislocation. Since then, distortion-free MRI near metal, like SEMAC-VAT MR, has shown its great clinical potential in diagnosing patients treated with THA.

Chun Kit Wong¹, Jamie X. M. Ho¹, and Mary Stephenson^1,2
1A*STAR-NUS Clinical Imaging Research Centre, Singapore, Singapore, ²Department of Medicine, National University of Singapore, Singapore, Singapore

Quantitative magnetization transfer (qMT) parameters can potentially be used as biomarker of diseases. In this study, qMT parameters’ nominal value are determined for selected muscle groups in healthy human subjects’ forearm, mid-thigh, and calf. Nominal values of qMT parameters are determined by taking the mean value across the subjects for each muscle group. From the results, strong correlations of qMT parameters between certain muscle groups within the same individual subjects are observed, suggesting that the qMT parameters' variation is biological in origin.

Chao Wu¹, Bin Zhao¹, Guangbin Wang¹, Shanshan Wang¹, and Hongjing Bao^1
1Shandong Medical Imaging Research Institute, Shandong university, Jinan, China, People's Republic of

This study aimed to measure the FA and ADC values by quantitative DTI at the tibial nerve and common peroneal nerve and determine whether DTI can be used in the DPN. 25 healthy volunteers and 13 patients with DPN were underwent MR examinations at 3T including DTI of knee. The FA values of both tibial nerve and common peroneal nerve in DPN patients were significantly lower than those in healthy volunteers. The ADC values in DPN patients were higher than those in healthy groups. DTI may thus be a reliable method to added diagnostic value in patients with DPN.

Jin Qu¹, Xinwei Lei¹, Ying ZHAN¹, Huixia Li¹, and Yu Zhang^2
1Tianjin First Center Hospital, Tianjin, China, People's Republic of, ²Philips Healthcare, Beijin, China, People's Republic of

The purpose of this study was to evaluate articular cartilage degeneration in healthy subjects and patients with knee joint-pain as the only clinical manifestation using T1ρ measurements and to examine the interrelationship between cartilage abnormalities. Quantitative assessment of cartilage was performed using T1ρ mapping technique in 5 healthy volunteers and 17 knee joint-pain patients. T1ρ values were signi?cantly elevated among patients with knee joint-pain compared to normal controls. Proteoglycan reduced in patients with knee joint-pain as the only clinical manifestation. Comparing to routine MR, T1ρ mapping could be more useful for these patients