Indirect MR Arthrography Of The Knee: An Initial Experimental Study

Objective: To explore the appearance and the value of Delayed Gadolinium-Enhanced MR in detecting articular cartilage dgeneration of the Rabbit knee.Methods: Twenty adult New Zealand rabbits were randomly divided into five groups (A,B,C,D,E for each).Intra-articular injection of Papain to establish animal models of different stages of cartilage degeneration in the right knees of A,B,C,D groups, and examined by MRI 24 hours, one week, one month and three months after injection. The knees were scanned bilaterally with T₁WI and 3D-FS-SPGR in sagittal plane . The signal intensity ratio between articular cartilage and the arounding soft tissue was measured at plane scan and 0,2,4 hours after intra-vein injection of gadolinium^2-(Gd-DTPA^2-). The articular cartilage were pathologically examined.Result: T₁WI sequence showed , no significant difference in the signal intensity ratio of articular cartilage and arounding soft tissue between processing group(right knee) and comparing group(left knee) and between four time periods (P>0.05) . In 3D-FS-SPGR sequence, significant difference in the signal intensity ratio between processing group(right knee) and comparing group(left knee) (P<0.05) ,the same significant difference in the signal intensity ratio between four groups (P<0.05) . The histochemical results of A,B,C,D group showed the process of cartilage degeneration. The SIR of articular cartilage and...