MR-IMAGING OF KNEE HYALINE CARTILAGE - EVALUATION OF 2-DIMENSIONAL AND 3-DIMENSIONAL SEQUENCES

Magnetic resonance (MR) imaging of cadaveric knees was performed to de termine optimal sequences for visualization of hyaline cartilage. Full -thickness cartilage lesions ranging in diameter from 1 to 5 mm and a partial-thickness cartilage lesion 15 mm in diameter were created in t he femoral articular surfaces of three cadaveric knees. The knees were then imaged with a 1.5-T imager with various two-dimensional and high -resolution three-dimensional (3D) techniques. After imaging, the knee specimens were sectioned for evaluation. Measurements of cartilage th ickness in fast spin-echo images correlated best with those in the gro ss specimen. Diffuse areas of cartilage thinning were also most accura tely identified with fast spinecho images. Small, focal cartilage defe cts were best delineated in 3D SPGR (spoiled GRASS [gradient-recalled acquisition in the steady state]) images.