Stefan Ruschke¹, Jan Syväri¹, Michael Dieckmeyer², Daniela Junker¹, Marcus R. Makowski¹, Thomas Baum², and Dimitrios C. Karampinos^1
1Department of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany, ²Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany

Single-voxel multi-TE STEAM MRS data of the 4^th/5^th lumber vertebrae from 260 subjects (age: 0.7-77.7years) was retrospectively analyzed to investigate physiological variations of water T2 (T2W) in bone marrow. The data was fitted using a joint-series T2-constrained time domain-based water–fat signal model. Linear regression analysis indicated significant negative correlations for T2W vs. age and PDFF for both sexes, respectively. Females showed significant longer T2W values compared to males. Multiple linear regression revealed PDFF and sex as significant predictors of T2W. Underlying physiological variations of T2W are of relevance in the study of T2 variations and T2-weighted parameters.

John P. Murray^1,2,3, Richard Lartey^1,3, Jeehun Kim^1,3, Mei Li^1,3, Sibaji Gaj^1,3, Brendan Eck^1,4, Donxing Xie^1,3, Carl Winalski^1,3,4, Faysal Altahawi^3,4, Morgan H. Jones^3,5, Bruce M Damon⁶, Laura J Huston⁷, Huyen T. Nguyen⁸, Michael V Knopp⁸, Kurt P. Spindler^3,5, and Xiaojuan Li^1,3,4
1Dept. of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States, ²Dept. of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, ³Program of Advanced Musculoskeletal Imaging (PAMI), Cleveland Clinic, Cleveland, OH, United States, ⁴Dept. of Diagnostic Radiology, Imaging Inst., Cleveland Clinic, Cleveland, OH, United States, ⁵Dept. of Orthopaedic Surgery, Orthopaedics and Rheumatology Inst., Cleveland, OH, United States, ⁶Dept. of Radiology, Vanderbilt University, Nashville, TN, United States, ⁷Dept. of Orthopaedics and Rehabilitation, Vanderbilt University, Nashville, TN, United States, ⁸Dept. of Radiology, Wright Ctr. Of Innovation in BioMed. Imaging, The Ohio State University, Columbus, OH, United States

This is a preliminary report for the MOON multivendor multisite 10 year follow up using quantitative MR imaging techniques for patients following ACL reconstruction. Imaging protocol was harmonized between sites and T1ρ and T2 imaging sequences that were cross-validated between sites and vendors were applied. Phantom data showed excellent intra-site repeatability and small inter-site variations. Significantly elevated cartilage T1ρ and T2 were observed in operated knees compared to contralateral knees. The preliminary results demonstrated feasibility of combining multi-site large cohort study with advanced quantitative MRI, with harmonized protocols and rigorous quality control for both data acquisition and processing.

Woo Young Kang¹, Suk-Joo Hong¹, Jinwoo Han¹, Yoonmi Choi¹, Chang Ho Kang², Kyung-sik Ahn², Baek Hyun Kim³, and Euddeum Shim^3
1Radiology, Korea University Guro Hospital, Seoul, Korea, Republic of, ²Radiology, Korea University Anam Hospital, Seoul, Korea, Republic of, ³Radiology, Korea University Ansan Hospital, Ansan, Korea, Republic of

Recently, MRI is increasingly used as an imaging tool to evaluate knee osteoarthritis. The purpose of this study is not only to evaluate the structural and biomechanical changes in osteoarthritis patients on MRI, but also to compare and analyze the imaging features and quantitative measurements evaluated by MRI with clinical severity.

Yanjun Hu¹, Cheng Xu¹, Yexin He¹, Ruizhu Wang¹, and Kaiyu Wang^2
1Magnetic Resonance Center, Shanxi Provincial People’s Hospital, Taiyuan, China, ²MR Research, GE Healthcare, Beijing, China

At present, whether patients with anterior cruciate ligament (ACL) injury can return to exercise lacks quantitative imaging indicators. In this study, ultra-short echo technique was used to evaluate the change of short T2 components like ligament in patients at chronic stage of ACL injury, finding that the proportion of short T2 componets (POS) in the overall signal can be used to reflect the extent of ACL injury and recovery. This study suggests that there are changes in the short-T2 components in patients with chronic ACL injury, and POS is superior to IKDC in assessing joint stability.

Zhenzhou Wu¹, Stefan Sommer^2,3, Xiaodong Zhong⁴, Kecheng Liu⁴, Jeehun Kim¹, Jillian Beveridge¹, Xiaoliang Zhang⁵, and Xiaojuan Li^1
1Program of Advanced Musculoskeletal Imaging (PAMI), Cleveland Clinic, Cleveland, OH, United States, ²Siemens Healthcare, Zurich, Switzerland, ³Swiss Center for Musculoskeletal Imaging (SCMI), Balgrist Campus, Zurich, Switzerland, ⁴Siemens Medical Solutions USA, Inc., Malvern, PA, United States, ⁵Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, United States

The connective tissues in the knee joint have ultrashort MR T2* relaxation times. Ultrashort echo time (UTE) sequences can offer a unique tool for measuring the fast-decaying signals in these tissues. However, T2* measures in these collagen-rich tissues are subject to magic angle effect. Previous studies on such orientation dependence and repeatability of UTE T2* in the knee are limited. The objectives of this study were to evaluate the repeatability of UTE T2*, and to investigate and compare the orientation dependence of T2* mapping between UTE and regular gradient echo (GRE) imaging sequences for whole knee imaging. 

Mei Wu^1,2, Yajun Ma¹, Guanyuan Ning², Saeed Jerban¹, Yanping Xue¹, Zhao Wei¹, Eric Y Chang^1,3, and Jiang Du^1
1Department of Radiology, University of California San Diego, San Diego, CA, United States, ²Department of Radiology, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, Guangzhou, China, ³Radiology Service, VA San Diego Healthcare System, San Diego, CA, United States

The three-dimensional adiabatic T1ρ prepared ultrashort echo time Cones (3D-UTE-Cones-AdiabT1ρ) sequence is a novel imaging technique that can provide magic angle-insensitive assessment of proteoglycan depletion in both short and long T2 tissues in the knee joint. We applied this sequence to healthy volunteers and patients with different degrees of OA for a systematic evaluation of its clinical performance. Results showed that the sequence could be used for quantitative evaluation of the knee cartilage degeneration, and that the 3D-UTE-Cones-AdiabT1ρ showed a significant positive relationship with WORMS and KL score，and significant difference in different extent and depth lesions of cartilage.

Brendan L. Eck^1,2, Richard Lartey^1,3, Dongxing Xie^1,3, Jeehun Kim^1,3, Carl S. Winalski^1,2,3, Bruce M. Damon⁴, Xiaodong Zhong⁵, Kecheng Liu⁵, Dimitris Karampinos⁶, Faysal Altahawi^1,2, Morgan H. Jones^1,7, Kurt P. Spindler^1,7, and Xiaojuan Li^1,2,3
1Program of Advanced Musculoskeletal Imaging, Cleveland Clinic, Cleveland, OH, United States, ²Diagnostic Radiology, Cleveland Clinic, Cleveland, OH, United States, ³Biomedical Engineering, Cleveland Clinic, Cleveland, OH, United States, ⁴Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States, ⁵MR R&D Collaborations, Siemens Medical Solutions USA, Inc., Malvern, PA, United States, ⁶Department of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany, ⁷Orthopaedic Surgery, Orthopaedics and Rheumatology Institute, Cleveland Clinic, Cleveland, OH, United States

Fatty infiltration in thigh skeletal muscle is a potential biomarker of osteoarthritis and post-traumatic osteoarthritis. Quantification of fatty infiltration is possible by Dixon MRI but is dependent on acquisition and processing. We evaluated five acquisition and processing techniques for reproducibility in phantom and healthy controls. Patients at 10-years post-ACL reconstruction were scanned to evaluate the potential for these techniques to detect thigh muscle fatty infiltration. Monopolar gradient acquisition and magnitude image-based processing improved the robustness of fat fraction quantification. Vendor-independent magnitude-based processing and vendor inline processing similarly quantified elevated fat fraction in the hamstring muscles of patients' ACL reconstructed legs.

Takayuki Sakai^1,2, Masami Yoneyama³, Atsuya Watanabe^4,5, Daichi Murayama¹, Shigehiro Ochi¹, and Tosiaki Miyati^6
1Radiology, Eastern Chiba Medical Center, Tonage, Japan, ²Division of Health Sciences, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan, ³Philips Japan, Tokyo, Japan, ⁴General Medical Services, Chiba University Graduate School of Medicine, Chiba, Japan, ⁵Orthopaedic Surgery, Eastern Chiba Medical Center, Chiba, Japan, ⁶Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan

Diffusion tensor imaging (DTI) has a severe problem such as high geometric distortion and body motion. To solve these problems, we attempted to apply a split acquisition of fast spin-echo signals for diffusion imaging (SPLICE) instead of conventional Mx-eliminated TSE-DTI. In addition, so as to improve the incoherent signal phase due to motion, SPLICE was combined with MultiVane (known as PROPELLER) which is to sample k-space in a rotating fashion using a set of radially directed blades. In this study, we evaluated the effect of accuracy and reproducibility of the quantitative values in lumbar nerve roots using MultiVane-SPLICE-DTI.

Esha Baidya Kayal¹, Devasenathipathy Kandasamy², Kedar Khare³, Raju Sharma², Sameer Bakhshi⁴, and Amit Mehndiratta^1,5
1Centre for Biomedical Engineering, Indian Institute of Technology Delhi, New Delhi, India, ²Department of Radio diagnosis, All India Institute of Medical Sciences Delhi, New Delhi, India, ³Department of Physics, Indian Institute of Technology Delhi, New Delhi, India, ⁴Department of Medical Oncology, Dr. B.R. Ambedkar Institute-Rotary Cancer Hospital (IRCH), All India Institute of Medical Sciences Delhi, New Delhi, India, ⁵Department of Biomedical Engineering, All India Institute of Medical Sciences Delhi, New Delhi, India

The aim of this study was to investigate the potential of Intravoxel incoherent motion (IVIM) parameters to predict event-free-survival (EFS) in patients with localized osteosarcoma treated by chemotherapy. Quantitative and IVIM parameter estimation and histogram analysis was performed in tumor volume at baseline. Imaging parameters along with clinical features were analyzed to assess their effects on EFS. Results showed, 25^th-percentile of perfusion coefficient (D*) and serum albumin level were significantly associated with EFS among localized osteosarcoma patients.

Jianwei Liao¹, Jin Liu¹, Yajun Ma², Xiaojun Chen¹, Wei Li¹, Lin Yao¹, Long Qian³, Jiang Du², and Shaolin Li^1
1Department of Radiology, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China, ²Department of Radiology, University of California, San Diego, CA, United States, ³MR Research, GE Healthcare, Guangzhou, China

Magnetization transfer ratio (MTR) has been used for assessment of macromolecules in biological tissues. Ultrashort echo time technique magnetization transfer (UTE-MT) can quantify both of short and long T2 tissues, may have potential to evaluate early disc herniation. The current study aims to assess the feasibility of UTE-MT quantification of posterior longitudinal ligament and nucleus pulposus for evaluation of early disc herniation. It was concluded that the UTE-MT sequence is feasible to quantify posterior longitudinal ligament and nucleus pulposus in lumbar. Posterior longitudinal ligament and nucleus pulposus UTE-MTR may provide a new opportunity for early prediction of lumbar disc herniation.

Shi Yin¹, Dou Weiqiang², and Ding Hongyuan^1
1The First Affiliated Hospital of Nanjing Medical University, Nanjing, China, ²GE Healthcare, MR Research, Beijing, P.R. China, Beijing, China

This study aims to if quantitative MR DTI technology combined with conventional MR can be applied to increase diagnostic efficiency and improve the diagnostic accuracy for lateral lumbar spinal canal stenosis in clinical. By measuring 99 patients, we found in extraspinal sub-regions of Lumbar nerve root, imaging findings of nerve edema, increased diameter and decreased FA values have an ideal diagnostic performance in LLSCS. Besides, among all include parameters, nerve edema demonstrated the best diagnostic performance. Therefore, conventional MR combined with quantitative MR DTI/DTT has a good performance for visualizing and quantitative diagnosis in lateral lumbar spinal canal stenosis.

Jin Liu¹, Yajun Ma², Jianwei Liao¹, Xiaojun Chen¹, Wei Li¹, Lin Yao¹, Long Qian³, Jiang Du², and Shaolin Li^1
1Department of Radiology, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China, ²Department of Radiology, University of California, San Diego, CA, United States, ³MR Research, GE Healthcare, Guangzhou, China

The 3D adiabatic inversion recovery prepared ultrashort TE cones (3D IR-UTE) sequence can image and quantify proton density assessment of short T2 water components in trabecular bone in vivo, and has the potential to diagnosis people with osteoporosis. The current study aims to prospective investigate the performance in diagnosing osteoporosis of IR-UTE sequence in human lumbar and to compare with quantitative computed tomography (QCT), dual-energy X-ray absorptiometry (DXA) and Fracture Risk Assessment Tool (FRAX) scores. It was concluded that IR-UTE was positively correlated to QCT and DXA, and was negatively correlated to FRAX scores.

Marco Barbieri¹, Lauren Watkins^1,2, Arjun D. Desai^1,3, Valentina Mazzoli¹, Elka Rubin¹, Andrew Schmidt¹, Garry E. Gold^1,2, Brian A. Hargreaves^1,2,3, Akshay S. Chaudhari^1,4, and Feliks Kogan^1
1Department of Radiology, Stanford University, Stanford, CA, United States, ²Department of Bioengineering, Stanford University, Stanford, CA, United States, ³Department of Electrical Engineering, Stanford University, Stanford, CA, United States, ⁴Department of Biomedical Data Science, Stanford University, Stanford, CA, United States

Bilateral T₂ mapping is a powerful tool for studying OA changes and investigating the role of between-knee asymmetry. qDESS allows for rapid T₂ mapping but uses a model that requires knowledge of the FA. Hence, B₁ inhomogeneities may affect the accuracy of T₂ measurements. We propose a pixel-wise B₁-correction method for qDESS T₂ mapping exploiting an auxiliary B₁ map to compute the actual FA used in the model. The technique was validated with phantom and with T₂ measurements of femoral cartilage in simultaneous bilateral knee imaging. The results showed that B1-correction can mitigate T₂ variations that were driven by B1-inhomogeneities.   

Ek T Tan¹, Erin C Argentieri¹, Madeleine A Gao¹, John Neri¹, Garry E Gold², Sharmila Majumdar³, Hollis G Potter¹, and Matthew F Koff^1
1Radiology and Imaging, Hospital for Special Surgery, New York, NY, United States, ²Stanford University, Stanford, CA, United States, ³University of California San Francisco, San Francisco, CA, United States

Ultra-short echo time (UTE) T2* relaxometry is sensitive to meniscal injury, but suffers from low SNR when acquired at high spatial resolution. Two denoising techniques – principal components analysis (PCA) denoising and model-based denoising (MD) were evaluated. Simulations show PCA and MD work complimentarily to reduce variance and bias. In N=14 college basketball (cases) players vs. N=13 controls, MD and MDPCA significantly reduced coefficient of variance in the lateral menisci. A significant difference in T2* of lateral and menisci was observed in cases vs. controls.

Ananya Goyal¹, Garry Gold¹, Feliks Kogan¹, and Lauren Watkins^1
1Stanford University, Stanford, CA, United States

Osteoarthritis (OA) is a debilitating disease characterized by joint structural degradation. Meniscal breakdown is linked to OA progression and can be studied through T2 relaxometry. In this work, we assess the effect of acute exercise on meniscus T2 relaxation times in individuals with OA. 12 individuals were scanned before and after performing a single-legged exercise. T2 relaxation times were computed using a qDESS sequence. We found that acute exercise did not affect the meniscal T2 values in OA subjects; however, significant changes in the maximal regional T2 change after exercise were observed that may be impacted by knee loading. 

Mohammad Zarenia¹, Volkan Emre Arpinar¹, Andrew S. Nencka¹, L. Tugan Muftuler², and Kevin M. Koch^1
1Department of Radiology, Medical College of Wisconsin, Milwaukee, WI, United States, ²Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI, United States

In this study, a methodology is developed for kinematic tracking and profiling of free-moving wrist carpal bones. The derived kinematic profiles consist of joint metrics computed and tracked during free wrist motion. Such metrics are hypothesized to be potentially valuable for diagnosis and management of joint dysfunction. Here, an advanced 4D MRI protocol is deployed to capture frames of unconstrained moving joints which are registered to a high-resolution fixed volume using a novel slab-to-volume boundary registration method. Using this registration approach on a sample subject-dataset,  concept demonstrations of a selection of metrics describing scaphoid-lunate kinematic motion are presented.

Varvara Choida^1,2, Timothy J.P. Bray^1,3, Alan Bainbridge⁴, Debajit Sen^2,5, Corinne Fisher^2,5, Maria Leandro^2,5, Coziana Ciurtin^2,5, and Margaret Hall-Craggs^1,3
1Centre for Medical Imaging, University College London, London, United Kingdom, ²Centre for Adolescent Rheumatology Versus Arthritis at UCL UCLH and GOSH, University College London, London, United Kingdom, ³Radiology, University College London Hospital, London, United Kingdom, ⁴Medical Physics, University College London Hospitals, London, United Kingdom, ⁵Adolescent and young adult Rheumatology, University College London Hospital, London, United Kingdom

MRI is used for the detection of synovitis in juvenile idiopathic arthritis (JIA). We developed a whole-body MRI protocol, consisting of coronal, post-contrast mDixon images, which is fast and offers good coverage of peripheral joints and spine. A prospective study including 32 adolescent and young adult patients with JIA revealed that 43.8% of patients had synovitis in at least one joint on imaging that was not detectable clinically. The proportion of patients with subclinical synovitis was similar in clinically active and inactive patients. This could lead to identification of unsuspected inflammation in JIA patients with potential impact on their treatment.

Halston J.C. Sandford¹, James W. MacKay², Lauren E. Watkins^1,3, Garry E. Gold^1,3,4, Feliks Kogan¹, and Valentina Mazzoli^1
1Radiology, Stanford University, Stanford, CA, United States, ²University of East Anglia, Norwich, United Kingdom, ³Bioengineering, Stanford University, Stanford, CA, United States, ⁴Orthopaedic Surgery, Stanford University, Stanford, CA, United States

Synovitis is associated with osteophyte development and osteoarthritis progression. The intensity of synovitis can be quantified by K^trans, obtained from DCE-MRI using gadolinium-based contrast agent. Diffusion Tensor Imaging (DTI) has shown potential for detecting synovitis without administering contrast agent. This study assessed the potential of DTI to quantify synovitis by comparing DTI parameters (MD, FA) to K^trans within the whole synovium and adjacent to osteophytes. We found that FA negatively associates with K^trans in both regions, while MD has a positive correlation only within the whole synovium. DTI is a promising tool for assessing intensity of synovitis in osteoarthritic knees.

Allen A Champagne^1,2, Don Brien², Andrew McGuire³, Paul Fenton⁴, Yousef A Marwan⁵, Paul A Martineau⁵, and Davide D Bardana^3
1School of Medicine, Queen's University, Kingston, ON, Canada, ²Center for Neuroscience Studies, Queen's University, Kingston, ON, Canada, ³Orthopedic Surgery, Queen's University, Kingston, ON, Canada, ⁴Diagnostic Radiology, Queen's University, Kingston, ON, Canada, ⁵Orthopedic Surgery, McGill University, Montreal, QC, Canada

Emergence of diffusion tensor imaging (DTI) has provided an exciting avenue to characterize the ligamentization process of the anterior cruciate ligament (ACL), following knee injury. However, a diverse, but limited, suite of published diffusion weighted sequences with varying parameters have posed a significant challenge to clinician-scientists wanting to integrate DTI as a tool to study the ACL. In this study, we provide a detailed comparison of DTI acquisitions toward the optimisation of ACL reconstruction using semi-automated fiber-based probabilistic tractography (FBPT), as a step-stone and reference for the clinical integration of DTI toward assessing microstructural integrity of the cruciate ligaments.

Jacob Thoenen¹, James W. MacKay^2,3, Kathryn J. Stevens¹, Tom D. Turmezei⁴, Akshay Chaudhari¹, Lauren E. Watkins¹, Emily J. McWalter⁵, Brian A. Hargreaves¹, Garry E. Gold¹, and Feliks Kogan^1
1Department of Radiology, Stanford University, Stanford, CA, United States, ²Department of Radiology, University of Cambridge, Cambridge, United Kingdom, ³Norwich Medical School, University of East Anglia, Norwich, United Kingdom, ⁴Department of Radiology, Norfolk and Norwich University Hospital, Norwich, United Kingdom, ⁵Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, SK, Canada

Quantitative double-echo in steady-state (qDESS) MRI has been proposed as an alternative to T1-weighted contrast enhanced MRI (CE-MRI) for evaluation of synovitis. In comparison with CE-MRI by, four radiologists, qDESS with a low diffusion gradient (qDESS_Low), and qDESS with a high diffusion gradient (qDESS_High) both showed good agreement to CE-MRI for the overall and regional impressions of synovitis, as well as good inter- and intra- rater agreement. Further, radiologists rated qDESS_Low and qDESS_High with moderate-to-high and moderate diagnostic confidence, respectively. This work shows the potential of the qDESS sequence as a non-contrast imaging technique for evaluation of synovitis.