手足部软组织滑膜肉瘤的MRI特征

MRI Characteristics of Soft Tissue Synovial Sarcoma of the Hand and Foot

目的探讨手足部软组织滑膜肉瘤(SS)的MRI表现。方法回顾性分析经病理证实的11例手足部SS患者的临床及MRI资料,分析其MRI特征。结果11例中肿瘤位于大鱼际1例,足跟部2例,足背部3例,足底部5例。MRI表现为肿瘤在TWI呈等信号5例,呈以等信号为主的混杂信号6例;脂肪饱和质子密度加权序列(FS PDWI)呈高信号3例,呈以高信号为主的混杂信号8例;瘤内见斑片状及线状低信号分隔8例,肿瘤包绕相邻肌腱或神经血管束6例,5例见瘤周水肿,4例出现“三重信号”,5例呈“铺路石”样改变;8例行MRI增强,肿瘤呈均匀强化3例,不均匀强化5例。结论手足部软组织肿瘤术前MRI检查是必要的;较大(≥5 cm)的SS多信号混杂,边界不清,瘤内多有出血、坏死、钙化及纤维分隔,瘤周可见水肿,增强不均匀明显强化;由于其发生部位少见,较易误诊,确诊仍需结合病理检查。

Objective To investigate the MRI characteristics of soft tissue synovial sarcoma(SS)in hand and foot.Methods The clinical and MRI data of eleven patients with hand and foot SS confirmed by pathology by retrospectively analyzed.Results Among the eleven cases,one case was located in thenar,two cases in heel,three cases in dorsal foot,and five cases in soles of feet.Five cases of tumor showed isointensity on TWI in MRI,and six cases showed isointensity mainly mixed signal.Fat-saturated proton density weighted imaging(FS PDWI)showed hyperintensity in three cases and hyperintensity mixed signal in eight cases.Patchy and linear hypointense signals separation was observed in eight cases,the tumor surrounded adjacent tendon or neurovascular bundle was six cases,and peritumoral edema was observed in five cases,“triple”sign in seven cases and“cobble”changes in five cases.The tumors showed homogeneous enhancement in three cases and inhomogeneous enhancement in five cases of the eight cases who MRI enhancement was performed.Conclusion Preoperative MRI examination of soft tissue tumor of hand and foot is necessary.Larger(≥5 cm)SS had mixed signals,unclear boundary,bleeding,necrosis,calcification and fibrous separation in the tumor,edema around the tumor,obvious uneven enhancement.Because of its rare location and easy to be misdiagnosed,the diagnosis still needs to be combined with pathological examination.