颈内动脉床旁动脉瘤对侧入路的显微外科解剖研究

Contralateral approach to paraclinoid ICA aneurysms: a study of microsurgical anatomy

目的:为经对侧手术入路治疗颈内动脉(ICA)床旁动脉瘤提供解剖学依据。方法:15例成人尸头标本,在手术显微镜下经对侧额颞入路模拟进行ICA床旁动脉瘤手术。暴露对侧ICA眼段、床段及其分支,进行解剖学观察,测量参数A和B以评估视交叉前池的大小。结果:在所有15例标本(共30侧)上,对侧ICA眼段和床段及垂体上动脉均被满意暴露。在14例标本(共28侧)上暴露了对侧眼动脉(OA)起始点。参数A和B分别为(8.0±1.2)mm(5.2￣10.4mm)和(13.6±1.7)mm(10.4￣17.3mm)。视交叉前池的大小对ICA床段的暴露无影响;视交叉前池越小,ICA眼段内侧面暴露的面积越少。暴露过程中无需牵拉视神经和ICA,或仅需轻微牵拉视神经。结论:对侧入路适用于直径较小的起源于ICA眼段近端及床段内侧面并向内侧突出的床旁动脉瘤。

Objective：To provide microsurgical basis for contralateral surgical approach to treat paraclinoid ICA aneurysms. Methods： On 15 adult cadaveric head specimens, proposed paraclinoid ICA aneurysms were approached via contralateral frontotemporal craniotomy under operating microscope. The ophthalmic and clinoid segment of ICA and their branches were exposed and observed. Parameters A and B were measured to estimate the size of prechiasmatic cistern. Results： In this study, the ophthalmic, clinoid segment of contralateral ICA and the contralateral superior hypophyseal artery were successfully exposed in all specimens （15 specimens, 30 sides）. The origin of contralateral ophthalmic arteries was exposed in 14 specimens （28 sides）. The means of parameter A and B were （8.0±1.2）（5.2-10.4）mm and （13.6±1.7） （ 10.4-17.3 ）mm, respectively. The size of prechiasmatic space did not affect the exposure ofclinoid segment of ICA. The less the size was, the less the exposed area of ophthalmic segment of ICA was. In the contralateral approach, the medial aspect of ophthalmic and clinoid segment of the contralateral ICA could be identified under the optic nerve without retracting of the contralateral optic nerve or with just minimal retraction. Conclusions： The contralateral surgical approach is a preferable choice to those selected aneurysms, which are small and originate from the medial aspect of proximal ophthalmic and clinoid segment of ICA and expend medially.