Evaluation of water content by spatially resolved transverse relaxation times of human articular cartilage

Non-invasive assessment of cartilage properties, specifically water content , could prove helpful in the diagnosis of early degenerative joint diseases . Transverse relaxation times T-2 of human articular cartilage (34 cartilag e slices of three donors) were measured on a pixel-by-pixel basis in a clin ical whole body MR system in vitro. In vivo feasibility to measure quantita tive T-2 maps was shown for human patellar cartilage. The relaxation times of cartilage with collagen in the radial zone oriented perpendicular to the magnetic field increased from approximately 10 ms near the bone to approxi mately 60 ms near the articular surface. Cartilage water content of the tib ial plateau and femoral condyles could be determined from the correlation w ith T-2 (R-2 = 0.71) with an error of approximately 2 wt.%. In vivo, direct ional variation would need to be considered. If confirmed in vivo, T-2 meas urements could potentially serve as a non-invasive tool for the evaluation of the status and distribution of water content in articular cartilage. (C) 2000 Elsevier Science Inc. All rights reserved.