Clinical & Translational Cartilage MRI

Monday 12 May 2014

Uchechukwuka D Monu^1,2, Emily J McWalter², Caroline D Jordan^2,3, Brian A Hargreaves^1,2, and Garry E Gold^2,3
1Electrical Engineering, Stanford University, Stanford, California, United States, ²Radiology, Stanford University, Stanford, California, United States,³Bioengineering, Stanford University, Stanford, California, United States

Osteoarthritis is a degenerative joint disease that may affect more than half of the ACL-injured population. Current MRI osteoarthritis studies often evaluate just a single slice from the medial and lateral compartments of the full knee, which may not fully describe the cartilage volume variation or longitudinal changes. In this work, we provide a method of visualizing quantitative maps of the entire cartilage surface using projection maps. T2 relaxation time differences between healthy volunteers and ACL-injured subjects are clear and the global percent short term CV of the implemented technique is comparable to the ROI approach reported in literature.

Jiang Du¹, Chantal Pauli², Shihong Li¹, Sheronda Statum¹, Won Bae¹, Eric Chang¹, and Christine B Chung^1
1Radiology, University of California, San Diego, San Diego, CA, United States, ²Pathology, University Hospital Zürich, Zürich, Switzerland

Both T2 and T1rho have been employed to evaluate articular cartilage degeneration. The magic angle effect in T2 relaxation is well understood. However, the literature regarding T1rho relaxation mechanisms is inconsistent. Some researchers reported much reduced or negligible magic angle effect in T1rho, while other researchers have reported significant magic angle effect in T1rho relaxation. Furthermore, magic angle effects in normal vs. abnormal cartilage are unknown. In this study we aimed to systematically evaluate the magic angle effect on T2 and T1rho in histological confirmed normal and abnormal cartilage at 3T

Rajeev Chaudhary¹, Fang Liu², Nade Sritanyaratana¹, Jarred M. Kaiser³, Samuel A. Hurley², Walter F. Block^1,2, and Richard X. Kijowski^4
1Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States, ²Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, ³Mechanical Engineering, University of Wisconsin-Madison, Madison, WI, United States, ⁴Radiology, University of Wisconsin-Madison, Madison, WI, United States

This study was performed to investigate the influence of the magic angle effect on multi-component T2 parameters measured using mcDESPOT. Ex-vivo articular cartilage specimens were imaged using mcDESPOT at angles of 0°, 30°, 55°, and 60° relative to the main magnetic field. Percent changes in T2 parameters from 0° to 55° where there was maximum magic angle effect was 42.9% for single-component T2, 20.0% for T2 of bulk water loosely bound to the macromolecular matrix, 40.0% for the T2 of water tightly bound to proteoglycan, and -4.9% for the fraction of water tightly bound to proteoglycan.

Cory Wyatt¹, Deepak Kumar¹, Karupppasamy Subburaj², Divya Narayanan³, Sonia Lee¹, Lorenzo Nardo¹, Thomas Link¹, Thomas Vail⁴, Richard Souza¹, and Sharmila Majumdar^1
1Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CALIFORNIA, United States, ²Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, United States, ³Bioengineering, University of California Berkeley, Berkeley, California, United States, ⁴Orthopaedic Surgery, University of California San Francisco, San Francisco, CALIFORNIA, United States

The purpose of this study was to measure T1rho and T2 relaxation times in vivo in healthy controls, subjects with mild OA, and subjects with femoroacetabular impingement (FAI). The volunteers were scanned with a segmented 3D SPGR MAPSS T1rho/T2 sequence on one hip and the cartilage was clinically scored for lesions. The femoral and acetabular cartilage were segmented separately and then segmented into 8 equal regions. Significant increases in the T1rho and T2 relaxation times were seen in the acetabular cartilage while no significant changes were seen in the femoral cartilage.

Edwin H. Oei^1,2, Weitian Chen³, Jason L. Dragoo⁴, and Garry E. Gold^1,5
1Radiology, Stanford University, Stanford, California, United States, ²Radiology, Erasmus MC, Rotterdam, ZH, Netherlands, ³GE Healthcare, Menlo Park, California, United States, ⁴Orthopaedic Surgery, Stanford University, Stanford, California, United States, ⁵Bioengineering, Stanford University, Stanford, California, United States

Although quantitative MRI for articular cartilage composition shows promise for early detection of osteoarthritis (OA), large-scale application is hampered by long scan times if added to routine MRI protocols. We assessed the performance of a quantitative 3D FSE T2 and T1rho mapping sequence to diagnose cruciate ligament and meniscal tears, bone marrow lesions, and cartilage defects. For anterior cruciate ligament and medial meniscal tears, diagnostic performance of the 3D FSE T1rho mapping sequence was good and superior to T2 mapping. This sequence may be used to replace routine clinical pulse sequences, enhancing scan time efficiency and potentially accelerating large-scale implementation.

Stefan Zbyn¹, Oliver Bieri², Vladimir Mlynarik¹, Vladimir Juras¹, and Siegfried Trattnig^1
1High Field MR Centre, Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria, ²Division of Radiological Physics, Department of Radiology, University of Basel Hospital, Basel, Switzerland

Coherent steady state sequences, such as FISP or TrueFISP, may provide higher SNR than spoiled gradient echo (SPGR). However, to our best knowledge, they have not yet been investigated for in vivo 23Na-MRI. In this study, in vivo and ex vivo knee measurements at 7T were performed to assess optimal measurement parameters for FISP and TrueFISP, and to evaluate their SNR compared to SPGR. FISP and TrueFISP provided significantly higher SNR than SPGR in cartilage, muscle and blood. The higher SNR may be traded off for higher resolution or shorter measurement times and help to get 23Na-MRI into clinical practice.

Won C Bae¹, Sheronda Statum¹, Reni Biswas¹, Darryl D D'Lima², Eric Y Chang^3,4, and Christine B Chung^3,4
1Department of Radiology, University of California, San Diego, San Diego, CA, United States, ²Scripps Clinic, La Jolla, CA, United States, ³VA San Diego Healthcare System, San Diego, CA, United States, ⁴University of California, San Diego, San Diego, CA, United States

UTE MRI enables direct evaluation of osteochondral junction of the knee. This study compared UTE MR morphology and histopathologic changes of the osteochondral junction, including duplication of tidemark and vascular invasion. While the occurrence of tidemark duplication was similar between UTE-normal and –abnormal samples, vascular invasion was significantly greater in UTE-abnormal samples. Further investigation is warranted to fully understand relationship between osteochondral changes and UTE MR morphology.

Ashley Williams¹, Yongxian Qian², and Constance R Chu^1
1Department of Orthopedic Surgery, Stanford University, Stanford, CA, United States, ²Radiology, University of Pittsburgh, Pittsburgh, PA, United States

This study tests the hypothesis that evaluation of the spatial distribution of cartilage UTE-T2* values, assessed via grey-level co-occurrence matrix texture statistics, will better detect sub-surface damage and disease progression to cartilage in ACL-injured subjects than mean UTE-T2* alone. Both cross-sectional comparisons with uninjured controls and longitudinal evaluations of ACL-injured subjects over 2 years after ligament reconstruction indicate that texture analyses provide evidence of progressive cartilage degeneration following ACL-injury that is not reflected in mean UTE-T2* value. Texture evaluations in this work augmented the ability of UTE-T2* mapping to quantitatively monitor cartilage status in knees at risk of developing OA.

Jasper van Tiel^1,2, Gyula Kotek¹, Max Reijman², Pieter K. Bos², Esther E. Bron^1,3, Stefan Klein^1,3, Jan A. Verhaar², Gabriel P. Krestin¹, Harrie Weinans^2,4, and Edwin H. Oei^1
1Radiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Zuid-Holland, Netherlands, ²Orthopedic Surgery, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Zuid-Holland, Netherlands, ³Medical Informatics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Zuid-Holland, Netherlands, ⁴Orthopedic Surgery, University Medical Center Utrecht, Utrecht, Utrecht, Netherlands

Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) has become a standard to quantitatively measure cartilage sulphated glycosaminoglycan (sGAG) content. T1rho-mapping has been proposed as non-contrast-enhanced alternative to dGEMRIC to also quantitatively measure cartilage sGAG content. However, no thorough validation studies comparing both techniques acquired in-vivo against a tissue reference standard for sGAG have been performed. Our preliminary results suggest that dGEMRIC can accurately measure articular cartilage sGAG content, whereas T1rho-mapping is not suitable for this purpose. Therefore, despite the need to use a contrast agent, we consider dGEMRIC to be superior to T1rho-mapping for quantitatively measuring cartilage sGAG content.

Jose G Raya¹, Florian Knoll¹, Lauren Burcaw¹, Sina Milani¹, Daniel K Sodickson¹, and Tobias K Block^1
1New York University Langone Medical Center, New York, NY, United States

We combine of a radial spin echo diffusion tensor imaging (RAISED) sequence for DTI of articular cartilage with a model-based iterative reconstruction, which directly calculates the diffusion tensor without reconstructing the intermediate diffusion-weighted images. This adds flexibility to the data acquisition. Purpose of this work was to assess value of different acquisition strategies for a model-based reconstruction. We tested four protocols with different resolutions, b-values and acquisitions times. We compared our model-based approach with the standard gridding reconstruction. We found improvement of the DTI parameters with the model based reconstruction and identify an optimal protocol for RAISED.