Representative T2 maps from a subject from the control cohort (left) and a subject from the incidence cohort (right). Cartilage T2 maps are median-filtered with a 3 × 3 kernal for visualization. Both subjects have no cartilage abnormalities (cartilage whole-organ magnetic resonance imaging scores (WORMS) = 0) and no pain (Western Ontario and McMaster Universities Osteoarthritis Index pain = 0); however, the subject from the incidence cohort has elevated mean T2 (39.12 versus 33.39 ms), elevated grey level co-occurrence matrix (GLCM) variance (311.63 versus 190.50), elevated GLCM contrast (466.16 versus 266.82), and elevated GLCM entropy (7.17 versus 6.80). Also, the control subject has intrasubstance abnormalities in the medial posterior meniscus (meniscus WORMS = 1). All other meniscus regions had no abnormalities (meniscus WORMS = 0).
Joseph et al. Arthritis Research & Therapy 2011 13:R153 doi:10.1186/ar3469