Microsurgical Anatomy And Clinical Applied Study Of Internal Carotid Artery Upper Space From Pterional Approach

Section oneMicrosurgical Anatomy of Perforating Arteries in Internal Carotid Artery Upper Space from Pterional ApproachObjective The purpose of this part was to study the microanatomy of perforating arteries in internal carotid artery upper space by pterional approach for clinical application.Methods 12 (24 sides) irritating cadaver heads were dissected through pterional approach, perforating arteries in internal carotid artery upper space were studied by the microscope. The diameter, course, relation of two groups of perforating arteries and distributing in anterior perforated substance of the perforating arteries were recorded. The data were statisted by SPSS 11.5 software.Results All perforating arteries originate from the dorsal surface of the main arteries' trunk. 8 sides carotid bifurcation had perforating arteries. 11 sides' middle cerebral arteries had medial lenticulostriate artery, short course and overlapped with another perforating arteries when entering the anterior perforated substance. 4 sides medial lenticulostriate artery coincided with perforating arteries in A1. All 24 sides middle cerebral arteries had middle lenticulostriate artery and lateral lenticulostriate artery. Most lenticulostriate arteries originated from anterior segment of the middle cerebral arteries' bifurcation. The earlier bifurcating in Ml of the middle cerebral arteries, the more perforating arteries originated. 22 sides the anterior cerebral arteries had perforating arteries, having many branches. The less perforating arteries in a main artery, the larger were their diameter.Conclusion The internal carotid artery upper space can use as an operating space. Part medial leticulostriate arteries and A1's perforating arteries are initiative cut in some patients can get a relatively big space in the internal carotid artery.Section twoClinical Application of Internal Carotid Artery Upper Space by Pterional ApproachObjective The purpose of this part was to study the clinical value of internal carotid artery upper space by pterional approach for tumor in sellar region clinical application.Methods The patients with large sella tumor showed by MRI were operated through internal carotid artery upper space combined with I-IV space to remove tumor. The symptom after operation and MRI were recorded.Results 11 patients had perforating arteries of furcation of internal carotid artery (35.5%), 15 patients medial lenticulostriate artery (48.4%) and 25 patients perforating arteries of A1 (80.6%). The first, second, third space and the internal carotid artery upper space became bigger becourse of the tumor's expensive growth. The optical nerve in 23 patients was crushed and became thin, match with the low visual acuity before operation. The internal carotid artery upper space could use as operating space in 7 patients because of absence of the lenticulostriate arteries and the perforating artery of A1 and bifurcation of internal carotid artery. There were some perforating arteries in the internal carotid arteries upper space in 24 patients, among which 17 patients needed to cut 1 or 2 perforating arteries for operation in this space. The perforating arteries couldn't cut more than 2 vessels and near the bifurcation of internal carotid artery. Its diameter was smaller than 0.3mm. 25 patients were total resected, 6 patients subtotal resected. Small fragment cerebral infarction in anteroinferior part of anterior limb of internal capsule appeared in 2 patients. All patients recovered consciousness after operation and hadn't hemiplegic's paralysis. Regressive visual acuity improved in 23 patients, aggravated in 1 patient. 6 patients' visual acuity unchanged. Transient diabetes insipidus appeared in 16 patients. 4 patients among them need long term medicine substitute therapy. No patient died in this group. The internal carotid space has five types: type I, big space has no perforating artery. This type fits to operation. Type II, big space has few perforating arteries. This type fits to operation. Type III, big space has many perforating arteries. This type needs cutting one or two perforating arteries for operation. Type IV, small space has no perforating artery. This type need to separate the structure surrounding to the internal carotid artery upper space. Type V, small space has many perforating arteries. This type doesn't fit to operation.Conclusion The internal carotid artery upper space can use as an operating space for resecting large sellar region tumors by pterional approach, which can increase the rate of tumor's total resection and decrease complication.