CT和MRI术前评估颞骨段面神经鞘瘤

目的探讨CT及MR检查术前评估颞骨段面神经鞘瘤的应用价值。方法回顾性分析9例经手术病理证实的颞骨段面神经鞘瘤的患者临床资料,9例患者均接受MR平扫及增强扫描,其中3例同时接受CT平扫及增强扫描。结果 9例面神经鞘瘤患者6例位于左侧,3例位于右侧,病变单独累及迷路段2例,鼓室段1例,乳突段1例;累及迷路段+鼓室段3例,鼓室段+乳突段2例。1例肿瘤与面神经可见分界,余8例均未见明显分界,2例可见乳突及外耳道软组织肿块。CT主要表现为面神经走形区边缘规则或不规则的软组织肿块,伴不同程度不规则或虫蚀状骨质破坏及面神经管增粗,部分可见骨质硬化;MRI表现为T1WI呈等信号,T2WI呈等或稍高信号的肿块影,增强扫描呈明显均匀或不均匀强化。结论 CT及MRI相互结合可准确地显示颞骨段面神经鞘瘤的位置和形态及周围情况,可作为面神经鞘瘤术前评估的首要检查方法。

CT and MRI in preoperative evaluation of intratemporal facial nerve schwannoma

Objective To investigate the value of CT and MRI in preoperative evaluation of intratemporal facial nerve schwannoma.Methods The clinical data of 9 intratemporal facial nerve schwannoma patients confirmed by pathology were retrospectively analyzed.Plain and enhanced MRI were performed in all 9 cases,in which 3 cases underwent CT plain and enhanced scans meanwhile.Results Among 9 cases,6 cases were on the left and 3 were on the right.The tumors involved labyrinth segment(n=2),tympanic segment(n=1),mastoid segment(n=1),labyrinth and tympanic segment(n=3),tympanic and mastoid segment(n=2).One case had obvious boundary,and the other 8 cases had no obvious boundary,and 2 cases had soft tissue mass in the mastoid and the external auditory canal.CT of the intratemporal facial nerve schwannoma main showed regular or irregular soft tissue mass in the margin of facial nerve contorts area,with varying degrees of irregular or insect damage bone destruction and facial nerve canal enlargement,partly visible bone sclerosis.MR images of the tumors showed isointense on T1WI and isointense or slightly hyperintense on T2WI,and marked enhancement was observed with signal uniform or non-uniform.Conclusion CT and MRI scans can accurately display the location,morphology and the surrounding situation,which can be used as the primary inspection method in preoperative assessment of intratemporal facial nerve schwannoma.