孤立性纤维瘤的CT和MRI诊断价值

Diagnostic value of CT and MRI scanning for solitary fibrous tumors

目的探讨全身孤立性纤维瘤的CT和MRI表现,以提高对本病的诊断水平。方法回顾性分析本院2013年1月至2018年4月经病理证实的33例胸膜及胸膜外孤立性纤维瘤病患者的CT和MRI表现,25例行CT检查,15例行MRI扫描,其中7例同时进行CT及MRI检查。结果 33例分别位于头颈、胸背部、腹盆腔及小腿软组织内。CT表现呈等、稍低密度肿块。MRI显示T1WI以等低信号为主,T2WI呈等、稍高信号或高低混杂信号,8例DWI呈等低信号,2例呈等低信号伴小片状稍高信号。32例行CT或MRI增强,20例呈"地图状"持续性强化,4例不均匀明显强化,1例均匀明显强化,7例轻中度持续强化。19例肿块内见粗大或点条状血管。结论孤立性纤维瘤多见地图状或不均匀持续性明显强化,少部分均匀或轻中度持续强化,尤其肿块内见粗大或点条状血管,DWI呈等低信号,ADC值升高,对术前诊断具有重要价值。

Objective To investigate the CT and MRI findings of systemic solitary fibrous tumors( SFTs) in order to improve their recognition. Methods Thirty-three patients with pathologically confirmed SFTs in pleural and extrapleural areas admitted in our hospital from January 2013 to April 2018 were enrolled in this study. Among them,25 underwent CT scanning,15 received MRI scanning,and 7 underwent both examinations. Their clinicopathological data and imaging features were collected and retrospectively analyzed.Results The tumor masses were located in the head and neck,chest and back,abdominopelvic cavity and soft tissues of the extremities in the 33 patients. On the CT images,the tumors appeared iso-to slightly hypoattenuated masses. While,on the MRI images,the majority of the tumors showed iso-to hypointensity on T1WI,and isodensity,slightly hyperintensity or a pattern of mixed hyper-and hypointensity on T2 WI. On diffusion weighted image( DWI),8 cases were found to be iso-to hypointense,and 2 cases were iso-to hypointense with patchy hyperintensity. After injection of a contrast agent,25 of the 32 cases demonstrated obviously intense enhancement and 7 cases were slightly to moderately enhanced on contrast-enhanced images,all of which persisted in the delayed phase. Twenty of the 25 cases showed consistently map-like enhancement,and 4 and 1 cases being heterogeneously and homogeneously enhanced,respectively. In addition,multiple big and small vessels were found on the contrast-enhanced images in 19 cases. Conclusion SFTs always persist in the delayed phase, most of which demonstrate map-like enhancement or heterogeneously persistent enhancement,while a few show homogeneous or slight to moderate persistent enhancement on contrast-enhanced images. Notably,image findings including masses with thick,or dotted and stripped blood vessels,iso-to hypointensity on DWI,and increased apparent diffusion coefficient( ADC)values are of great value for preoperative diagnosis of SFTs.