MRI筋膜尾征诊断结节性筋膜炎的价值

Application value of fascial tail sign at MRI in the detection of nodular fasciitis： a retrospective study

目的探讨MRI筋膜尾征对结节性筋膜炎（NF）的诊断价值。方法回顾性分析经手术病理证实的19例软组织NF及53例以纤维成分为主的非NF软组织肿瘤患者的MRI资料，分别作为病例组和对照组。观察两组患者MR图像上筋膜尾征出现概率，绘制ROC曲线，计算筋膜尾征对NF诊断的敏感度、特异度、Youden指数和ROC曲线下面积。采用Pearsonz。独立性检验分析筋膜尾征与NF之间的相关性。结果病例组17例（89．5％）出现筋膜尾征，对照组6例（11．3％）出现筋膜尾征。MRI筋膜尾征对NF诊断的敏感度为89．5％，特异度为88．7％，Youden指数0．782，ROC曲线下面积为0．891。筋膜尾征与NF之间存在较好的关联性（χ^2=39．294，P〈0．05，r=0．594）。结论筋膜尾征对软组织NF的诊断有较高的敏感度和特异度，在临床诊断中有一定的价值，但仍需与部分具侵袭性的软组织肿瘤相鉴别。

Objective To explore the value of fascial tail sign at MR images in the detection of nodular fasciitis （NF）. Methods A retrospective analysis of MR images was performed in 19 patients with pathologically proven NF of the soft tissue and 53 patients with a variety of other fibrous-predominant tumors. MR manifestations of all cases were reviewed by two experienced musculoskeletal radiologists using a single blind method. The presence of fascial tail on MR images were evaluated. ROC was used to assess the value of fascial tail sign in the detection of NF. Sensitivity, specificity, Youden index and area under ROC curve were calculated. The association between the presence of fascial tail sign on MRI and pathological classification of NF was analyzed by Pearson chi-square test for independence. Results Fascial tail was present in 17 cases （89.5%） of the study group and in 6 cases （11.3%） of the control group, respectively, yielding a sensitivity of 89.5%, a specificity of 88.7%, a Youden index of 0.782 and an area under ROC curve of 0.891. The fascia] tail sign was significantly associated with NF （χ^2=39.294, P〈0.05, r=0.594）. Conclusions Fascial tail sign at MRI is a moderately specific and sensitive for the diagnosis of NF relative to fibrous-predominant tumors. It can be used in differentiate between NF and aggressive soft tissue tumors.