Longitudinal analysis of MRI T2 knee cartilage laminar organization in a subset of patients from the osteoarthritis initiative: A texture approach

✍ Scribed by Julio Carballido-Gamio; Gabby B. Joseph; John A. Lynch; Thomas M. Link; Sharmila Majumdar

• Book ID: 102955585
• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 549 KB
• Volume: 65
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.22693

✦ Synopsis

Cartilage magnetic resonance imaging T 2 relaxation time is sensitive to hydration, collagen content, and tissue anisotropy, and a potential imaging-based biomarker for knee osteoarthritis. This longitudinal pilot study presents an improved cartilage flattening technique that facilitates texture analysis using graylevel co-occurrence matrices parallel and perpendicular to the cartilage layers, and the application of this technique to the knee cartilage of 13 subjects of the osteoarthritis initiative at baseline, 1-year follow-up, and 2-year follow-up. Cartilage flattening showed minimum distortion (~0.5 ms) of mean T 2 values between nonflattened and flattened T 2 maps. Gray-level cooccurrence matrices texture analysis of flattened T 2 maps detected a cartilage laminar organization at baseline, 1-year follow-up, and 2-year follow-up by yielding significant (P < 0.05) differences between texture parameters perpendicular and parallel to the cartilage layers. Tendencies showed higher contrast, dissimilarity, angular second moment, and energy perpendicular to the cartilage layers; and higher homogeneity, entropy, variance, and correlation parallel to them. Significant (P < 0.05) longitudinal texture changes were also detected reflecting subtle signs of a laminar disruption. Tendencies showed decreasing contrast, dissimilarity, and entropy; and increasing homogeneity, energy, and correlation. Results of this study warrant further investigation to complete the assessment of the usefulness of the presented methodology in the study of knee osteoarthritis.