Correlation between histology and quantitative MRI relaxation parameters in articular cartilage

Abstract. Osteoarthritis (OA) is the most common joint disease in the world. In osteoarthritis, articular cartilage experiences degeneration, which causes pain, disability and inflammation, among other symptoms in the joint. The diagnosis of osteoarthritis is made at a very late stage, as many symptoms and morphological changes in radiological images do not appear until the degeneration of the articular cartilage is advanced. Hence, new diagnosis methods for early OA diagnostics are welcome. One potential method for early OA diagnosis is quantitative MRI (qMRI). In OA, articular cartilage experiences histological changes; changes in collagen content, proteoglycan content, water content, and collagen orientation. At early OA, these changes are very slight. However, qMRI is a potential method to detect these changes. In qMRI quantitative relaxation parameters, such as T1, T1rho, and T2 can be determined, which correlate with the histology of the cartilage. When histological changes leading to osteoarthritis are known, relaxation parameters may be a potential biomarker for early OA diagnosis