Diagnostic value of different sequences of magnetic resonance imaging in repaired meniscus

Objective To evaluate the diagnostic value of different sequences of magnetic resonance imaging (MRI) in repaired meniscus.Methods From September 2002 to December 2008,118 patients (130 menisci) underwent arthroscopic meniscus suture in our hospital,including 94 males and 24 females,aged from 15 to 50 years (average,25.7t7.5 years).All patients underwent MRI and second-look arthroscopy postoperatively.Different sequences of MRI were taken to evaluate the grade of meniscal signal at repaired site and the slices involved by grade 3 signal.The diagnostic sensitivity,specificity,accuracy,positive predict value (PPV) and negative predict value (NPV) were calculated for each sequence by using second-look arthroscopy as the gold standard.Results The total healing rate was 80.8％ (105/130) by second-look arthroscopy,which was higher than that by different sequences of MRI.The integrated T2 sequence held the highest diagnostic value,and the sensitivity,specificity,accuracy,PPV and NPV were 76.0％,71.4％,72.3％,38.8％ and 92.6％,respectively.According to the second-look arthroscopy result,the menisci were divided into the healed group and unhealed group.In the healed group,28.6％ of cases (30/105) showed grade 3 signal in MRI,which was less than that (76.0％) in the unhealed group.The rate of the new grade 3 signal (8.6％) and the slices involved by grade 3 signal (0.8±1.0) in the healed group were less than those (16.0％ and 3.0±2.0) in the unhealed group.Conclusion The diagnostic value of the integrated T2 sequence is encouraging with high sensitivity,specificity and accuracy.The new grade 3 signal in the repaired meniscus usually implies that the meniscus is not healed. Key words: Menisci, tibial;  Suture techniques;  Magnetic resonance imaging;  Arthroscopy