Cerebral Arterial Occlusion Did Not Promote the Prevalence of Cerebral Amyloid Angiopathy

Background: An impairment of amyloid-beta (A beta) clearance has been suggested in Alzheimer's disease. Perivascular drainage along cerebrovascular vessels is considered an important amyloid clearance pathway. Objective: This study examined the effect of reduced arterial pulsation that could cause an impairment in cerebral amyloid drainage on the prevalence of cortical microbleeds (CMBs), a surrogate marker for cerebral amyloid angiopathy (CAA). Methods: Patients who lost depiction of either side of the carotid artery or the middle cerebral artery on magnetic resonance angiography were studied. Those who showed acute cerebral infarction or a previous cortical cerebral infarction were excluded. The number of CMBs was counted on the occluded and non-occluded sides of the brain in each subject. The number of subjects who showed more CMBs on the occluded side of the brain was compared with the number of subjects who showed more CMBs on the non-occluded side of the brain. Results: Twenty-eight patients were studied. The extent of lacunar infarction and white matter lesions was not different, irrespective of the occluded vessels or the distribution of CMBs. The prevalence of CMBs was not different between the occluded and non-occluded sides of the brain. Conclusion: In this cross-sectional study, reduction of arterial pulsation was not associated with a higher prevalence of CAA. Therefore, reduced arterial pulsation alone may not be enough to promote CAA.