眶上锁孔入路去除眶顶的解剖学研究

目的探讨眶上锁孔入路中去除眶顶的应用价值。方法取成人尸头标本8例,模拟眶上锁孔入路并去除眶顶,比较去除眶顶前后Willis环周围血管最大显露程度、显露面积及不同深度靶点显露角度的差异。结果去除眶顶前后,前交通动脉复合体、同侧大脑中动脉的显露范围有显著性差异(P< 0.01)。在基底动脉顶端位置较高的标本中,去除眶顶有助于其显露;对鞍区其他深部结构如大脑后动脉、小脑上动脉的显露无显著性差别(P> 0.05)。去除眶顶后,手术显露面积(864.2 mm2)较去除眶顶前(494.9 mm2)明显增加;工作角度平均增加34.2%。结论去除眶顶对位置较高的前交通动脉复合体、A2段近端和位置较高的基底动脉顶端分叉部的显露有实际意义;应根据病变的特点确定是否去除眶顶。

Anatomic study on orbital roof osteotomy via supraorbital approach

Objective To investigate the value of orbital roof osteotomy via supraorbital keyhole approach. Methods Supraorbital keyhole approach and a variation of this approach combined with roof osteotomy (transorbital approach) were performed on 8 cadaver head specimens. For each surgical exposure, the maximal exposure scope of the circle of Willis was recorded .The working areas were determined by using triangles defined with anatomic points. The exposure angles of those approaches for the same target point were also determined with neuronavigation system. Results The maximal exposure lengths of the ipsilateral middle cerebral artery and anterior communicating artery (AcoA) complex increased significantly after the orbital roof was removed (P < 0.01). In two cadavers, basilar artery bifurcation, which can not be seen because of the high location in supraorbital keyhole approach, could be exposed after removing the orbital roof. No improvement was observed in exposure of basilar artery and posterior cerebral arteries (PCA) and superior cerebellar artery (P > 0.05). The working areas were significantly greater with the transorbital keyhole approach (864.2 mm2) than that with the supraorbital approach (494.9 mm2). The angle of attack increased by 34.2%. Conclusion Only in the cases with higher AcoA, or higher basilar artery bifurcation, removal of the orbital roof is necessary and helpful. The anatomic features for each patient should be considered before removing orbital roof.