The application of MR gagCEST in quantitative assessment of articular cartilage

Osteoarthritis (OA) is characterized by progressive degeneration of articular cartilage while the excessive degradation and loss of glycosaminoglycan (GAG) is the earliest histological change in cartilage degeneration. Conventional imaging techniques are not sensitive to the change. When OA was diagnosed by the conventional image techniques, it already had developed to late and irreversible stage. MR glycosaminoglycan chemical exchange saturation transfer (gagCEST) as a novel quantitative MR technique provides a noninvasive and accurate measurement of GAG content in cartilage, it has bright application prospect in early diagnosis and treatment monitoring of OA. This review emphasizes on the mechanism, advantages and weaknesses of MR gagCEST technology, and the clinical application in evaluation of OA were also included. (authors)