视神经与蝶窦解剖关系及其临床意义的CT研究

CT Study and Clinical Significance of Anatomical Relationship between Optic Nerve and Sphenoid Sinus

目的：通过CT观察并探讨视神经与蝶窦关系的变化规律,为视神经管减压术提供依据.方法：随机选择鼻窦无明显异常的成人头部CT扫描350例,观察视神经隆凸的出现率,根据蝶窦内有无隆凸,将其分为视神经隆凸组和非隆凸组,各组随机选择30例进行蝶窦体积测量,比较两组之间体积的差异.在计算机上用Mimics软件勾画蝶窦、视神经等结构的轮廓,软件自动给出蝶窦的体积和三维重建图.结果：蝶窦腔内有视神经隆凸56例（16%）,其中24侧的视神经直接裸露在蝶窦内,35例伴前床突气化.后者中有21侧气化的前床突腔隙与蝶窦腔融合,视神经游离于蝶窦腔内;19侧气化的前床突腔隙与后筛窦融合,视神经行走于筛窦内.无视神经隆凸组的蝶窦体积为（15.26±11.22）cm3,有视神经隆凸的蝶窦体积为（26.72±5.77）cm3.两组比较差异有统计学意义（P＜0.05）.通过蝶窦、视神经的三维立体重建模型的观察,其有48%的视神经主要与蝶窦相邻,有52%的视神经主要与后筛窦相邻.结论：视神经隆凸与蝶窦体积相关,体积越大,视神经隆凸的出现率就高,从而提示是否实施经蝶窦的视神经减压术等内镜手术蝶窦体积是其考虑的主要因素之一.部分受试者的视神经与蝶窦接触较少,如经蝶窦入路有可能难以寻找视神经.

Objective：To explore the variation rule of the relationship between the optic nerve （ON） and sphenoid sinuses（SS） by computed tomography and provide the surgery basis for optic nerve canal decom- pression. Methods：350 CT scans of adult heads without nasal sinuses abnormity were randomly selected and incidence of optic nerve protrusion in the sphenoid sinus was observed . According to with or without protrusion , two groups were formed and 30 of each group were randomly selected . Volume of sphenoid sinus was measured and the volume between two groups were compared , the outline of sphenoid sinus and optic nerve were drawn with Mimics software . Then the volume and 3D reconstructed model of sphenoid sinus and optic nerve were given automatically. Results： The optic nerve protrusion in the sphenoid sinus cavity was found in 56 cases （16%）. Pneumatization of anterior clinoid process （ACD） was found in 35 cases . Among them , the fusion of ACD pneumatization cavity and sphenoid sinuses existed in 21 cases, optic nerve was crossing in the sphenoid sinuses and fusion of ACD pneumatization cavity with posterior ethmoid sinuses existed in 19 cases ,optic nerve was crossing in the ethmoid sinuses. Immediate nudity of ON in spheniod sinus were found in 24 cases. The volume of sphenoid sinus was measured and it was （ 15.26 ±11.22 ） cm^3 in non - optic nerve protrusion group and （26.72 ± 5.77 ）cm^3 in optic nerve protrusion group. The differences had statistical significance between two groups（P 〈0.05）. By observing the 3D reconstructed model of ON and SS, it was found that 48% of ON were mainly adjacent to SS and the others （52%） were mainly adjacent to posterior ethmoid sinuses. Conclusions：There is relationship from ON protrusion to the volume of sphenoid sinus. The larger the volume is , the higher the rate of ON protrusion will be. Accordingly , surgical solution should be ensured by SS pneumatization before endoscope surgery. Optic nerve of some subjects have less contact with SS so that it will be difficult to find ON by transsphenoidal surgeries.