An Anatomical Study of Operating Space in the Sellar Region via Transpterional Approach

Objective To put forward anatomic parameters about the sellar region for microneurosurgery. Methods The surgical anatomy of the operating spaces and vessels/nerves nearby in the sellar region was studied in 10 cadaver brains. Results M1 segment of the middle cerebral artery forms its primary branches 18.4± 3.2 mm to the bifurcation of the internal carotid artery(ICA), and sends out 14 perforating branches. The distance between the posterior border of tuberculum sellae and the anterior border of optic chiasma was 5.6±1.1 mm, the maximum distance between the medial borders of the bilateral optic nerves was 10.5±1.4 mm. ICA sends out about 3.2 superior hypophyseal arteries which supply the optic nerves, optic chiasma and hypophyseal stem. The length of the three edges of the optic-carotid triangle was 6.6±0.6 mm,6.9±0.7 mm and 4.0±0.4 mm respectively, the length of the three edges of the carotid-tentorial triangle was 8.8±0.7 mm,6.7±0.7 mm and 4.4±1.0 mm respectively. The posterior communicating artery sends out 7.4 perforating branches, its length was 18.7±2.3 mm, its origin point was 7.7±0.5 mm to the bifurcation of ICA. The origin point of anterior choroidal artery was 4.4±0.6mm to the bifurcation of ICA, the length of the anterior communicating artery was 1.9±0.3mm. Heubner reccurent artery arises from A2 segment of the anterior cerebral artery, 0.9±0.2 mm above anterior communicating artery, and supplies to corpus callosum, basal ganglia, hypothalamus and frontal lobe. Conclusion The present results may be a guide for the microsurgery of the sellar region to avoid injury of the important nerves and vessels.