Abstract
Arteriosclerotic changes are most frequently observed in cerebral angiography of the elderly. In addition, cerebral arteriosclerosis is considered as a main cause of stroke. But relatively little work has been done about the predisposing factors of arteriosclerosis visualized by cerebral angiography. Carotid angiograms were reviewed to investigate the risk factors of cerebral arteriosclerosis in 315 patients who visited Research Institute of Brain and Blood Vessels, Akita from 1969 to 1974. In all patients examined in the present study some reason for carotid angiography was present, but any organic brain disease could not be confirmed other than cerebral arteriosclerosis. Arteriosclerotic lesions were classified into three grade according to the degree of stenosis and the extent of arterial wall irregularity in three arterial groups of extracranial carotid arteries, intracranial major arteries and intracranial small arteries. The grade of cerebral arteriosclerosis was correlated with age, blood pressure and serum cholesterol level. The results were as follows.
1) Age was closely related with arteriosclerosis in each of three arterial groups. The frequency of arteriosclerosis in intracranial major arteries was higher than in other arterial groups.
2) An increase in the severity of arteriosclerosis of each arterial group was noted in the presence of hypertension. But statistical analysis of cases matched in age revealed a significant difference only in assessement of intracranial small arteries at ages of fifty (P<0.001) and sixty years (P<0.01). Therefore, it was concluded that a much closer relationship existed between blood pressure and arteriosclerosis in intracranial small arteries than in other arterial groups.
3) In hypertensive cases, the frequency of arteriosclerosis in extracranial carotid and intracranial major arteries tended to increase with serum cholesterol level. The relationship between serum cholesterol and arteriosclerosis of intracranial major arteries was significant (P<0.05). Especially stenosis of greater than one-fourth was observed in 26.5% of cases with serum cholesterol over 210mg/dl and its incidence was about five times those of less than 184mg/dl. No significant relationship between cerebral arteriosclerosis and cholesterol level was found in the cases without hypertension.
