踝关节色素沉着绒毛结节性滑膜炎的影像学诊断

目的 探讨踝关节色素沉着绒毛结节性滑膜炎(pigmented villonodular synovitis,PVNS)的影像学诊断.方法 回顾性分析7例经手术病理证实的踝关节PVNS的临床及影像学资料.7例均行MRI榆查,其中1例行增强扫描,4例行X线检查,1例行CT检查.结果 X线表现:踝关节前后方脂肪垫被软组织密度影代替,邻近骨呈压迫性骨质吸收.CT表现:踝关节周围,下胫、腓联合及距下关节软组织肿块影,清晰显示邻近受压骨质的硬化边.MRI表现:7例均表现为弥漫性、分叶状软组织肿块.在T_1WI上呈低信号,脂肪抑制T_2WI上呈不均匀混杂信号,4例以低信号为主,3例见散在斑片状低信号影.5例病变包绕邻近拇长屈肌腱,3例累及距下关节.1例行增强扫描呈明显强化.结论 典型MRI表现结合临床检查能够对踝关节PVNS作出诊断.

Imaging Diagnosis of Pigmented Villonodular Synovitis in the Ankle Joint

Objective To discuss the imaging diagnosis of pigmented villonodular synovitis(PVNS)in the ankle joint. Methods Clinical and imaging data of 7 cases with PVNS in the ankle joint confirmed by histopathology were analyzed retrospectively. All cases were examined by MRI, and 1 of them by contrast enhanced MRI. X-ray and CT examination were performed in 4 and 1 case, respectively. Results X-ray showed soft tissue density anterior and posterior to the ankle joint,and adjacent bone displayed having pressure bone resorption. CT scan showed sclerotic margins of the adjacent bone clearly. MRI scans demonstrated diffuse lobulated soft tissue masses, the lesions identified low signal intensity on T_1WI, heterogeneous signal intensity on fat suppressed T_2WI ,of them,4 cases showed mainly low signal and 3 cases displayed scattered patch low signal. The flexor pollicis longus muscle tendons were enveloped by the lesions in 5 and the subtalar joint involved in 3. The lesion enhanced obviously after MR imaging in one case. Conclusion Typical MRI appearances in combination with clinical examinations can provide diagnosis of PVNS in the ankle joint.