COMPARISON OF LOW-FIELD (0.2 TESLA) AND HIGH-FIELD (1.5 TESLA) MAGNETIC-RESONANCE-IMAGING OF THE KNEE-JOINT

In order to evaluate the reliability of low-field magnetic resonance i maging (MRI), we examined 22 patients using a 0.2-Tesla magnet unit in comparison with a 1.5-Tesla system, The MRI findings were compared wi th the intraoperative findings, Concerning the diagnosis of meniscal t ears, the gradings of both systems differed only in three cases, The s pecificity was 97% (both systems), the sensitivity 83% (1.5 T) versus 75% (0.2 T), The sensitivity and specificity for detection of tears of the anterior cruciate ligament were 100% and 75%, respectively, for b oth systems. The gradings differed only in two cases. In our series we found 6 full-thickness cartilage defects that were all detected with the high-field imaging system. They were missed by the low-field imagi ng system in 5 cases, The results suggest that both systems are reliab le in diagnosing meniscal tears and ruptures of the anterior cruciate ligament.