Diagnostic and quantitative imaging of knee osteoarthritis

Articular cartilage is a connective tissue, that provides virtually frictionless articulation between bones in a joint. Degenerative joint disease, osteoarthritis (OA), is the most common type of arthritis. During its development, cartilage is progressively lost, decreasing the functional capacity of the joint. Currently it is diagnosed with radiography, which might not show changes in cartilage tissue during the early stages of OA. In radiography, cartilage degeneration might be visible only when OA has progressed to advanced stage. The lack of effective treatment methods for advanced stage of OA has generated interest towards the development of biomarkers for the detection of early OA. Magnetic resonance imaging (MRI), especially relaxation time mapping, is able to provide accurate information on early changes in cartilage structure and is considered to be one of the best candidates for the detection of early OA. Morphological assessment of three-dimensional MRI, on the other hand, can be used as an indicator of the rate of cartilage loss. In this work, OA is reviewed and the current methods for diagnosing OA are studied. Relaxation time mapping and morphological assessment of articular cartilage are current research interests and these methods will also be discussed