Jaovisidha Suphaneewan, Virayavanich Warapat, Woratanarat Patarawan, Siriwongpairat Pimjai
Department of Radiology, Ramathibodi Hospital School of Medicine, Mahidol University, Rama 6 Street, Bangkok 10400, Thailand.
J Med Assoc Thai. 2009 Dec;92(12):1662-8.
To study and diagnose meniscal tear of the knee using 3-Tesla (3-T) magnetic resonance imaging (MRI) compared with arthroscopy.
One hundred twenty eight consecutive patients who underwent MRI of the knee using a 3-T magnet between April 2007 and Nov 2008 were included in this study. The inclusion criteria were the patients who had (i) subsequent knee arthroscopy, (ii) available medical records, and (iii) no history of meniscal surgery. Their MR images were retrospectively reviewed by two radiologists with consensus agreement. The diagnostic values for diagnosing meniscal tears were evaluated and compared to the arthroscopic results.
Thirty-two patients (64 menisci) were included; 26 males and 6 females, mean age was 36.4 years (range 19-62). The mean interval between MRI and arthroscopy was 93 days. To diagnose tear of medial, lateral, and both menisci; the sensitivity was 100%, 90%, 100%; the specificity was 77%, 73%, 50%; the accuracy was 91%, 78%, 84%; the positive predictive value (PPV) was 86%, 60%, 81%; and the negative predictive value (NPV) was 100%, 94%, 100%, respectively. False positive MR findings were found predominantly at the posterior horn and at the peripheral third of the menisci. By dividing the patients into 2 groups according to the mean MRI-arthroscopy interval (< 93 and > 93 days): increased sensitivity and NPV of detecting lateral meniscal tear; increased specificity, accuracy, and PPV of both meniscal tear was observed in the longer duration group, but there was no statistical significance in the present study.
The present results with 3-T MRI revealed high sensitivity and NP V comparable to the literature, thus supporting previous studies that if a meniscal tear is not seen on 3-T MRI, it is highly unlikely to be present. False positive MR findings found predominantly at the posterior horn and at the peripheral third of the menisci. The longer the MRI-arthroscopy interval yielded increased diagnosing values of meniscal tear but there is no statistical significance in the present study
采用3特斯拉（3-T）磁共振成像（MRI）与关节镜检查相比较，研究并诊断膝关节半月板撕裂。
本研究纳入了2007年4月至2008年11月期间连续128例行3-T膝关节MRI检查的患者。纳入标准为：（i）随后接受膝关节镜检查；（ii）有可用的病历；（iii）无半月板手术史。两名放射科医生对他们的MR图像进行回顾性审查并达成共识。评估诊断半月板撕裂的诊断价值，并与关节镜检查结果进行比较。
纳入32例患者（64个半月板）；男性26例，女性6例，平均年龄36.4岁（范围19-62岁）。MRI与关节镜检查的平均间隔时间为93天。诊断内侧、外侧和双侧半月板撕裂时，敏感性分别为100%、90%、100%；特异性分别为77%、73%、50%；准确性分别为91%、78%、84%；阳性预测值（PPV）分别为86%、60%、81%；阴性预测值（NPV）分别为100%、94%、100%。MRI假阳性结果主要见于半月板后角和半月板外周三分之一处。根据MRI与关节镜检查的平均间隔时间（<93天和>93天）将患者分为两组：检测外侧半月板撕裂的敏感性和NPV增加；在间隔时间较长的组中，双侧半月板撕裂的特异性、准确性和PPV均增加，但本研究无统计学意义。
本研究中3-T MRI的结果显示出与文献相当的高敏感性和NPV，从而支持了先前的研究，即如果在3-T MRI上未发现半月板撕裂，则极不可能存在。MRI假阳性结果主要见于半月板后角和半月板外周三分之一处。MRI与关节镜检查间隔时间越长，半月板撕裂的诊断价值增加，但本研究无统计学意义
