Quantitative MR Analysis of Articular Cartilage:  MSK Applications
Monday 20 April 2009
Room 312 11:00-13:00


Xiaojuan Li and Hollis G. Potter

11:00  70.

Morphological and Biochemical (T2) MR Evaluation and Comparison of Cartilage Repair Tissue of the Patella and the Medial Femoral Condyle

    Goetz Hannes Welsch1, Tallal Charles Mamisch2, Lukas Zak3, Sebastian Quirbach1, Stefan Marlovits3, Siegfried Trattnig1
MR Center, Department of Radiology, Medical University of Vienna, Vienna, Austria; 2Department of Orthopedic Surgery, University of Berne, Berne, Switzerland; 3Center for Joints and Cartilage, Department of Trauma Surgery, Medical University of Vienna, Vienna, Austria
    The objective of this study was to use advanced MR techniques to evaluate and compare cartilage repair tissue after matrix-associated autologous chondrocyte transplantation in the patella and in the medial femoral condyle (MFC). For morphological evaluation, the MR observation of cartilage repair tissue (MOCART) score was used, with a 3D-True-FISP sequence. For biochemical assessment, T2-mapping was prepared by a multi-echo spin-echo approach with particular attention to the zonal structure of cartilage. The assessment of cartilage repair tissue of the patella and the MFC demonstrated comparable morphological results, whereas biochemical T2 values showed differences, possibly due to dissimilar biomechanical loading conditions.
11:12 71.

Effect of Knee Alignment on T2 Relaxation Time of Articular Cartilage

    Risto Ojala1, Riikka Partanen1, Ilkka Hannila1, Eveliina Lammentausta1, Marianne Haapea1, Osmo Tervonen1,2, Miika T. Nieminen1,2
Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland; 2Department of Radiology, University of Oulu, Oulu, Finland
    Varus and valgus malalignment of the knee is known to increase the risk of medial and lateral osteoarthritis, respectively. To assess whether knee alignment influences T2 relaxation time of tibio-femoral cartilage, T2 was measured at the weight-bearing cartilages of 30 patients with knee symptoms and 20 asymptomatic volunteers at 1.5T. Varus alignment resulted in a significant increase in T2 in the whole medial tibial cartilage and the deep parts of the femoral cartilage. Valgus alignment caused an increase only in tibial cartilage, predominantly in the medial compartment. T2 mapping may provide a sensitive tool to detect early degenerative cartilage changes.
11:24 72.

Multiexponential T2 Analysis in Cartilage Degraded Using Different Enzymatic Protocols

    David A. Reiter1, Ligaya Roque1, Richard G. Spencer1
National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
    We sought to improve the specificity for cartilage matrix degradation through multiexponential analysis of T2 relaxation, which can delineate macromolecular compartments with varying water fraction and mobility. Multiexponential T2 analysis of control cartilage and of cartilage subjected to three enzymatic degradation protocols showed distinct patterns, consistent with the known actions of the degradative enzymes used. In contrast, while monoexponential T2 values increased with degradation, there was no enzyme-specificity in this increase. Therefore, multiexponential T2 analysis demonstrates greatly improved specificity over standard monoexponential T2 analysis to changes in cartilage matrix, indicating the diagnostic potential of such analysis for detecting cartilage disease.
11:36 73.

Evaluation of Cartilage T2 Using Loading in Situ MRI in Early Osteoarthritis with Hip Dysplasia


Takashi Nishii1, Toshiyuki Shiomi2, Hisashi Tanaka3, Youichi Yamazaki4, Kenya Murase4, Takashi Sakai2, Masaki Takao2, Hideki Yoshikawa2, Nobuhiko Sugano1
Department of Orthopaedic Medical Engineering, Osaka University Medical School, Osaka, Japan; 2Department of Orthopaedic Surgery, Osaka University Medical School, Osaka, Japan; 3Department of Radiology, Osaka University Medical School, Osaka, Japan; 4Department of Medical Physics & Engineering, Osaka University Medical School, Osaka, Japan

    Cartilage T2 with use of loading in situ MR imaging (50% of body weight) was evaluated in 9 patients with hip dysplasia and 9 normal volunteers, for evaluation of cartilage pressure distribution in vivo. There was significant decrease of T2 by loading at the outer zone of the acetabular cartilage and inner zone of the femoral cartilage in dysplastic hips (p<0.05). Loading in situ MR imaging with T2 assessment may allow biomechanical assessment of pathological conditions related to localized stress concentration and have prognostic significance for osteoarthritic changes in hip dysplasia.
11:48  74.

 Localised Cartilage Assessment with Three-Dimensional DGEMRIC in Subjects with Normal and Cam-Type Abnormal Hip Joint  Morphology. an Assay of Early Disease.

    Tom C.B. Pollard1, Eugene G. McNally1, Derek C. Wilson2, Burkhard Maedler3, David R. Wilson2, Marion Watson1, Andrew J. Carr1
Nuffield Department of Orthopaedic Surgery, University of Oxford, Oxford, UK; 2Department of Orthopaedics, University of British Columbia, Vancouver, BC, Canada; 3Philips Healthcare, Vancouver, BC, Canada

The majority of cases of hip osteoarthritis are caused by morphological abnormalities, such as the cam deformity. Treating such deformity may prevent disease progression. A sensitive, responsive assay of chondral damage is needed to assess treatment efficacy.

dGEMRIC was performed on subjects without radiographic osteoarthritis, with and without cam deformities. The ratio of the T1-index in the anterosuperior acetabular cartilage, divided by the T1-index for the whole joint cartilage, was significantly different between the two groups.

Using dGEMRIC to map chondral damage may have advantages over a single measure of whole joint cartilage in OA. dGEMRIC offers promise as an assay of early hip osteoarthritis.

12:00 75. 

 Factors Affecting Accuracy of T1 Estimates in Vivo by Variable Flip Angle Approach for DGEMRIC

    Angela Manuel1, Wei Li1, Vladimir Jellus2, Timothy Hughes2, Pottumarthi V. Prasad1
1NorthShore University HealthSystem, Evanston, IL, USA; 2Healthcare Sector, Siemens AG, Erlangen, Germany
    Previous experience with phantoms has shown good agreement in T1s obtained by standard 2D IR-TSE and 3D VFA techniques. However, the level of agreement in vivo was less. In order to determine the reason behind this inaccuracy, we investigated a number of potential factors, such as number of flip angles used, fitting routines, and effects of B1 inhomogeneity. Our results suggest that increasing the number of flip angles had minimal or no effect on improving the agreement between the techniques and that B1 inhomogeneity may be most responsible for the apparent poor agreement between 3D VFA and 2D IR-TSE estimates.
12:12 76.

Longitudinal Evaluation of Cartilage Degeneration in ACL-Injured Knees Using MR T1ρ Quantification and Laminar Analysis

    Daniel Kuo1, Alekos A. Theologis1,2, Radu I. Bolbos1, Julio Carballido-Gamio1, ChunBong Benjamin Ma3, Xiaojuan Li1
Musculoskeletal Quantitative Imaging Research (MQIR), Department of Radiology, University of California, San Francisco, San Francisco, CA, USA; 2School of Medicine, University of California, San Francisco, San Francisco, CA, USA; 3Department of Orthopaedic Surgery, University of California, San Francisco, San Francisco, CA, USA
    Patients with ACL injuries have a high risk of developing osteoarthritis (OA) despite ACL reconstruction. However, the mechanism of OA development in ACL-injured knees remains elusive. Nine ACL-injured patients were studied over 2 years to evaluate changes in bone marrow edema-like lesions (BMEL) and cartilage degeneration. Degenerative changes were evaluated using MR T1ρ relaxation time quantification and laminar analysis. Although BMEL resolved significantly over time, T1ρ values in BMEL-overlying cartilage were elevated at both baseline and follow-ups, suggesting irreversible damage in those regions. T1ρ values were also elevated in superficial layers of the weight-bearing cartilage sub-compartments of the medial knee.
12:24 77.

Demonstration of the Pre-Clinical Efficacy of Aggrecanase Selective Inhibitor by T1p MRI

    Reddy Beesam Shashank1, Ashwini Anumandla2, Eric Albert Mellon2, Jennifer H. Lee3, Jingsong Wang3, Ravinder Reddy2
MMRRCC,Radiology, University of Pennsylvania, Philadelphia, PA, USA; 2MMRRCC,Radiology, University of Pennsylvania, USA; 3Wyeth Research, Collegeville, USA
    To demonstrate the effectiveness of T1p MRI as a pre-clinical tool in drug development.
12:36 78.

Ultrashort TE MRI of the Osteochondral Junction of the Knee at 3T:Identification of Anatomic Structures Contributing to Signal Intensity


Won C. Bae1, Jerry R. Dwek2, Richard Znamirowski1, Sheronda Statum1, Juan C. Hermida3, Darryl D. DíLima4, Robert L. Sah5, Jiang Du1, Christine B. Chung1
Radiology, UC San Diego, San Diego, CA, USA; 2Childrenís Hospital and Health Center, UC San Diego, San Diego, CA, USA; 3Scripps Clinic; 4Scripps Clinic, La Jolla, CA, USA; 5Bioengineering, UC San Diego, La Jolla, CA, USA

    Joint diseases may involve abnormalities in the junction between cartilage and bone. Using Ultrashort Time-to-Echo (UTE) MRI techniques, tissues with short T2 properties at this junction become visible, unlike when conventional sequences are used. UTE MR signature of human osteochondral tissues near the junction (uncalcified cartilage, calcified cartilage and subchondral bone) was determined, using experimental treatments to isolate specific components. Both calcified cartilage and the deepest layer of uncalcified cartilage were identified as tissues contributing to the UTE signal. This study has implications for clinical evaluation of the osteochondral junction and introduces new opportunities for assessing joint disease using MRI.
12:48 79.

 Evaluation of Articular Cartilage of Lumbar Facet Joints with UTE MR Imaging and Multi-Echo SE T2 Mapping Techniques


Hatice Tuba Sanal1, Tobias Mett2, Sheronda Statum1, Jiang Du1, Richard Znamirowski1, Graeme Bydder1, Christine Chung1
Radiology, UCSD, San Diego, CA, USA; 2THE VIENNA SCHOOLS OF MEDICINE, Vienna, Austria


Evaluation of articular cartilage (AC) of lumbar facet joints (LFJS) with UTE/Multi-Echo SE T2 Mapping.  Objective: Qualitatively/quantitatively evaluate morphology and biochemical integrity of AC of LFJs.  Materials and methods: A cadaveric lumbar spine was evaluated with standard clinical, UTE sequences, multi-echo SE T2 mapping and T1/T2* measurement.  Results: Mean T2 value of superficial layer of cartilage was 53 ms on abnormal side and 40ms on normal side. T2* value of calcified layer of cartilage on abnormal side and normal side were calculated 6.8 ms and 2.1 respectively.

Conclusion/Discussion: Quantitative evaluation of FJís cartilage might be useful for lower back pain.