腹内型韧带样纤维瘤病的影像表现

The Imaging Findings of Intra-Abdominal Desmoid-Type Fibromatosis

目的探讨腹内型韧带样纤维瘤病的影像表现。方法搜集经手术病理证实的12例腹内型韧带样纤维瘤病患者的临床及影像资料,患者术前行CT或MRI平扫及多期增强扫描,结合文献回顾性分析其影像特征。结果 8例CT检查均为单发病灶,3例位于肠系膜,密度均匀,其中2例与周围肠管分界不清,增强扫描动脉期轻度强化,静脉期呈持续性强化,延迟期病灶强化达峰值;1例边界清楚,推压周围肠管,使其移位,胃、小肠、结肠壁可见多发结节。1例位于胃结肠韧带,边界不清,密度不均,可见大片状低密度区,增强扫描低密度区无强化。2例位于后腹膜,1例呈类圆形,1例形态不规则,其中1例推压腹主动脉及下腔静脉,增强扫描轻度强化。2例盆腔病灶均位于右侧髂窝,呈分叶状,边界不清,增强扫描不均匀中度强化。4例MRI检查均为单发病灶,其中2例位于肠系膜,呈类圆形,边界清晰;2例位于盆腔,呈分叶状,边界不清。4例T_1WI为不均匀等低信号,T_2WI信号较复杂,可见条索状、斑片状低信号区及高信号囊变区,增强扫描渐进性不均匀强化。结论腹内型韧带样纤维瘤病的影像表现具有一定的特征性,MR T_2WI呈稍高信号,病灶内常见低信号纤维条索影,增强扫描动脉期和门静脉期较低的强化程度、延迟强化的特征对鉴别诊断有一定的帮助,提高其影像征象的认识有助于正确诊断。

Objective To investigate the imaging features of intraabdominal desmoid-type fibromatosis.Methods Imaging features of intraabdominal desmoid-type fibromatosis in twelve patients confirmed by postoperative histopathology were reviewed retrospectively.Moreover,the related literature was reviewed.Results Eight cases of CT for single lesions,three lesions located in mesentery,homogeneous in density,two lesions of boundary which was unclear.The enhanced scanning arterial phase was slightly enhanced,and the venous phase was continuously enhanced,and the delayed lesion intensified to the peak.One lesion was well-circumscribed,multiple nodules were seen in the stomach,the small intestine and the colon wall.One lesion was located in the gastrocolic ligament,ill-defined margins,heterogeneous in density,large patches of low density,the low density area was not enhanced.Two lesions were located in the retroperitoneal space,one of which presented a circular shape,and one case was irregular in shape with mild enhancement,one of them displacing the abdominal aorta and the inferior vena cava.The two lesions in the pelvic cavity were located in the right iliac fossa,which was lobular,well-circumscribed and with heterogeneous moderate enhancement.On MRI,All of the four cases were single lesions,two of which were located in the mesentery,with a round shape and clear boundary.Two cases were located in the pelvic cavity,which were lobular and ill-defined,homogeneous isointensity or mild hypointensity on T1-weighted images,heterogenous mild hyperintenslty on T2-weighted and strip low signal on all pulse sequences.The lesions showed intense heterogeneous enhancement in arterial phase,and gradual and prolonged enhancement in portal venous and delayed phases.Conclusion Intraabdominal desmoid-type fibromatosis have certain characteristic imaging features.On MRI,mild hyperintensity on T2-weighted images,and low signal on all pulse sequences,enhancement CT showed lower degree of enhancement in the arterial phase and portal venous phase,delayed enhancement.To improve the understanding of the image findings of intraabdominal desmoid-type fibromatosis is helpful so as to correctly diagnose this lesion.