外生性面神经雪旺氏细胞瘤的形成

为探讨外生性面神经雪旺氏细胞瘤的病理来源及病因 ,对 152 6耳颞骨连续切片进行组织病理学观察。结果发现 :39耳在面神经骨性管裂处显示神经外膜先天性缺损 ,神经主干由此疝出。其中31耳 ,在疝出面神经凸面有明显的雪旺氏细胞增生。这 31耳中 ,有 12耳在卵圆窗上方 ,1耳在面神经第二膝部形成小的外生性雪旺氏细胞瘤。提示 :管裂处神经外膜的先天性缺损是面神经由此疝出的组织解剖学原因。面神经疝出可能是刺激雪旺氏细胞增生 ,以致形成外生性面神经雪旺氏细胞瘤的直接原因。

The development of outgrowing schwannomas of the facial nerve

To explore the pathologic origins and actural pathogenesis of these outgrowing facial Schwannomas,the 1 526 temporal bones collected at the University of Minnesota were histopathologicaly observated under microscope.39 showed congenitally defective epineurium and herniation of the facial nerve at dehiscences in its bony canal.31 of these showing Schwann cell proliferation on the convex surface of the herniation, and 12 of these 31 were small outgrowing Schwannonas above the oval window, and 1 of 31 grew one tumor on second turn segment of the facial nerve.Our findings suggested that the epineural congenital defect found over dehiscence area of the facial bony canal provides a histoanatomic cause precipitating extrusion of the facial nerve from such dehiscences, and the extrusion is probably the main direct cause of stimulating Schwann cell proliferation which can form outgrowing facial Schwannomas.