膝关节盘状半月板的MRI征象分析

目的：明确5种MRI征象对膝关节盘状半月板的诊断价值。方法：分析532例经关节镜证实的膝关节MRI图像,其中包括43例盘状半月板及其不同程度损伤的MRI图像。在不告知关节镜结果的条件下,由2名有经验的放射科医生分别对诊断盘状半月板的5个征象及其不同程度损伤进行评价,差异协商解决。分别计算出每种征象的敏感性。结果：冠状面上外侧半月板中部最窄处〉15 mm或与外侧平台关节面的比值〉50%;矢状面上（层厚4 mm）半月板的前后角相连形成“领结样”改变达四层或四层以上。此两种征象的敏感性分别为86.0%和74.1%,诊断率最具可靠性。盘状半月板常合并变性、撕裂,且不同程度的损伤可影响盘状半月板征象的准确判断。结论：盘状半月板在MRI有多种征象,各种征象对诊断的能力有所不同。当合并不同程度损伤时亦会影响其征象的正确判断。

MR imaging of Discoid Menisci of the knee: evaluation with signs

Objective:To determine the value of five MRI imaging signs in diagnosing discoid menisci and injury of the knee.Methods:MRI imaging of 532 knees with subsequent attenuated exams were retrospectively evaluated,based on the results of arthroscopy of 43 discoid menisci..two radiologist evaluated each MRI exam independently with discrepancies resolved by consensus.Each MRI exam was analyzed for the five sign,sensitivity for diagnosing discoid menisci were calculated for the presence of each individual sign.Results: The ratio of width of meniscus to that of tibia plateau was over 50%.On the sagittal plane,there were consecutive 4 layers or more showed"tie"change which derived form the connection of anterior and posterior horns.The sensitivities of there two signs ranged was 86.0% and 74.1%.The following two signs had higher value.Discoid menisci were often combined with degeneration and laceration,different injure can affect the accurate judgment of signs in discoid menisci.Conclusions: Discoid menisci have many signs on MRI imaging,different signs have different diagnosing ability.The accurate judgment of signs can be affected when combined with different injure.