Vertebrobasilar dolichoectasia as a risk factor for cerebral microbleeds

Background Both vertebrobasilar dolichoectasia (VBD) and cerebral microbleeds (CMBs) are related with the risk of intracerebral hemorrhage. We aimed to examine the relationship between the VBD and CMB in ischaemic stroke patients. Methods A consecutive series of 182 patients hospitalized because of ischaemic stroke or transient ischaemic attack (TIA), and who underwent gradient echo brain magnetic resonance imaging were retrospectively recruited from a prospective stroke registry. CMB locations were categorized into anterior and posterior circulation. Ectasia was defined as basilar artery (BA) diameter >4.5mm, and dolichosis, as either BA bifurcation above the suprasellar cistern or lateral to the margin of the clivus or dorsum sellae. Whether VBD is associated with CMB anywhere in the brain or in anterior or posterior circulation territories was analysed using binary and multinomial logistic regression models. Results Twenty-four subjects (13.2%) had VBD and 48 (26.4%) had CMBs. CMBs were more frequently observed in patients with VBD than without (66.7% vs. 20.3%, P<0.001). VBD was significantly associated with CMBs in any location (crude odds ratio, 7.88; 95% confidence interval, 3.1020.02), in the posterior circulation territory only (9.63; 2.6034.94), and in both territories (9.25; 3.4026.29), but not in the anterior circulation only (1.14; 0.00911.20). These associations remained unchanged after adjusting for age, gender, hypertension, leukoaraiosis and stroke subtype. Conclusions VBD in patients with ischaemic stroke or TIA is independently associated with CMBs, especially in the posterior circulation territory.