Abstract
Recently the STA-MCA anastomosis (STA... superficial temporal artery, MCA... middle cerebral artery) is often applied for the case of the stricture or occlusion of MCA trunk or the internal carotid artery. The purpose of this paper is to clarify the difference of the nature of the arteriosclerotic change of both arterial branches used for this anastomosis histologically comparing to other cerebral arteries.
Histological specimens were taken from surgical biopsy as well as fresh autopsy brain and were examined microscopically and electron-microscopically. As the biopsy material, specimens were taken; one from the arterial stump of MCA at the STA-MCA anastomosis and another small piece from the arteriole in the anterior portion of the temporal lobe. As the autpsy specimen, the brain was irrigated with glutal solution soon after death and cerebral arteries were examined systematically.
As the result, the following findings were confirmed. 1) The arterial wall of the STA was almost three times thicker than that of the cortical branch of MCA in ordinary condition. 2) The arteriosclerotic change of the cortical branch of the MCA was mostly slight and STA often showed characteristic thickening of intima which was composed of mature smooth muscle cells and massive collagen fiber. 3) The arteriosclerotic change was apparently more marked in the MCA trunk and the lenticulo-striate arteries than the cortical branch of MCA and STA.
