三叉神经痛与面肌痉挛显微血管减压的显微解剖

目的 研究小脑脑桥角区的解剖结构,为三叉神经痛与面肌痉挛微血管减压手术提供解剖学依据.方法 16例成人头颅湿标本,采用乙状窦后入路,对小脑脑桥角区行显微解剖研究.结果 (1)上界为上项线中点下2 cm,下界为枕骨大孔上缘1 cm,内侧界距枕窦缘3 cm,外侧界为乳突基底内侧0.5 cm的骨窗中心恰与面听神经垂直对应,是微血管减压的最佳骨窗.(2)脑池段三叉神经与面听神经最宽距离平均为(11.19±0.12)mm.(3)岩静脉距离面听神经平均为(10.05±0.11)mm.结论 该区手术骨窗中心位置可行最佳选择.利用岩静脉与面听神经的间隙行微血管减压术无需切断岩静脉.

Microdissection study of CPA for the functional neuprosurgery

Objective To study the anatomy relationship among the vessles, nerves and bone landmarks in the region of CPA and provide operation-related anatomy knowledge for microvascular decompression of trigeminal neuralgia and hemifacial spasm. Method 16 cadaver specimens were used. 32 sides of CPA region were dissected with retrosigmoid approach. The optimal bone window center for Ⅶ,Ⅷ cranial nerves was localized and the relationship of nerves and vessels were observed and measured. Results (1)The bone window was 2 cm under the midpoint of superior nuchal line superiorly, 1 cm above superior margin of foramen magnum inferiorly, 3 cm lateral to occipital sinus medially, 0.5 cm medial to mamillary process base laterally. The center of the bone window was properly above the Ⅶ,Ⅷ cranial nerves. (2)The widest distance between the Ⅶ,Ⅷ cranial nerves and trigeminal nerve was 10.20～12.18 mm, mean (11.19±0. 12)mm in the cistern. (3)The distance between Ⅶ,Ⅷ cranial nerve and petrosal vein is 9.10±11.22 mm, mean(10.05±0.11)mm,and this interspace can be used to perform microvascular decompression without cutting off petrosal vein. Conclusions The bone window for microvascular decompression in CPA can be optimized to a special location. The locations of trigeminal nerve and Ⅶ,Ⅷ cranial nerves are relatively constant. Therefore these nerves can be used as intraoperative landmarks. The microvascular decompression operations can be performed in the interspace between nerves and vessles without cutting off petrosal vein.