The influence of atherosclerosis and ectasia on cerebral blood flow.

Of 65 patients with neurological disorders examined with rapid serial angiography of the carotid artery, 24 had normal cerebral arteries, 17 atherosclerosis, 11 arterial ectasia and 13 both kinds of vascular changes. These patients were examined for hemispherical rCBF determination on the same occasion, using the 133Xenon clearance method. Primarily, the patients were examined without general anaesthesia, and they did not have acute illness, trauma, or angiographic evidence of a focal intracranial lesion. In addition, other parameters such as arterial size, ventricular size, cerebral circulation time, age, and sex were determined. All these data were studied statistically in a series of multiple regression analyses with a computer. No significant differences in rCBF could be found between cases with ectasia, atherosclerosis and without any kind of vascular changes. However, the mean value of rCBF in patients with atherosclerosis and in patients with intracranial ectasia was below the normal mean value, although it did not differ significantly from this value. Nor was any influence on the rCBF found in patients with marked stenosis of the internal carotid artery and those with slight stenosis.