Matrix-based autologous chondrocyte implantation for cartilage repair: noninvasive monitoring by high-resolution magnetic resonance imaging

Objective ring of articular cartilage repair after matrix-associated autologous chondrocyte implantation (MACI) by a new grading and point-scale system based on noninvasive cartilage-specific magnetic resonance imaging (MRI) protocol. ts and Methods patients, postoperative high-resolution MRI follow-up examinations at 4, 12, 24 and 52 weeks after matrix-based ACI for cartilage repair were initiated. pair tissue was described with separate variables: degree of defect repair in width and length, surface, structure and signal intensity of the repair tissue, and status of the subchondral lamina and bone. For these variables, a grading system with point-scale evaluation was applied, and the mean average values were calculated for every follow-up MR exam of each patient. s patients, an incomplete filling of the defect improved to complete filling (6 patients) or less incomplete (4 patients) filling of the defect. Three cases of implant hypertrophy returned to normal within 1 year. Complete filling of the defect by repair tissue was found in 2 patients from the beginning. Integration was complete in 10 cases. Improvement of incomplete to complete integration was found in 3 patients. gnal intensity of the implant developed to native cartilage signal in 13 patients. an average values increased from the 4th to the 52nd week in 17 of 20 patients and decreased in 3 of 20 patients. sion esolution MRI provides a noninvasive tool for monitoring the development of cartilage repair tissue in MACI over time and helps to differentiate abnormal repair tissue from a normal maturation process.