侵袭性纤维瘤病的CT与MRI表现

目的 讨论侵袭性纤维瘤病的CT和MRI表现，特别是MRI的信号特征，评价MRI对该病的诊断价值。方法 回顾分析9例经手术病理证实的侵袭性纤维瘤病的CT和MRI表现。结果 CT检出8例，平扫5例病灶呈高密度，3例呈等密度；边界清晰1例，模糊7例；3例病灶边缘呈爪状生长；增强后病灶均呈不规则强化；均未见包膜。MRI检出9例，肿瘤均沿肌纤维生长，2例病灶局限在单一肌肉，7例累及多块肌肉；2例肿瘤境界清楚、可见不完整包膜，7例境界不清、无包膜、边缘呈爪状生长；与肌肉比较平扫病灶T1WI呈等信号4例、呈低信号5例，T2WI均呈高信号；增强后病灶信号增高。短时反转恢复序列（STIR）扫描，病灶内未见脂肪组织。结论 MRI信号的差异主要反映了病灶的组织学成分的不同。MRI比CT更能精确地显示病灶的形态和范围，对侵袭性纤维瘤病的诊断和鉴别诊断有重要价值。

CT and MRI manifestations of aggressive fibromatosis

Objective To discuss CT and MRI features of aggressive fibromatosis (AF), especially the characteristic signs of MRI, and to evaluate the value of MRI in diagnosing the disease. Methods The CT and MRI studies in 9 cases with pathologically proven AF were retrospectively analyzed. Results Among 9 cases with AF, one cases could not be discovered by CT and all cases could be discovered by MRI. Appearances of lesion were infiltrating in 7 cases and mass-like in 2 cases. All cases were without calcification and lipo-tissue in the lesion and without edema on adjacent muscle structures. A homogeneous density and high density was seen on CT plain scans and high density on contrast enhanced scans. On MRI scans, variable signal intensity was demonstrated on T 1WI, and high signal intensity on T 2WI, as well as increased signal intensity after contrast enhancement. The signal characteristics primarily reflected the underlying histologic composition of the lesions. Conclusion MRI is more excellent than CT in delineating the site, shape, and extent of these lesions. MRI is valuable in detecting and differentiating AF.