Basilar Artery Dolichoectasia Is Associated with Paramedian Pontine Infarction

Abstract

Background: Basilar artery (BA) dolichoectasia (dilatative arteriopathy) (BAD) causes arterial elongation and enlargement with subsequent hemodynamic changes leading to thrombosis, microembolization and brainstem compression. Little is known about the association between BAD and the pattern of pontine infarct in patients without BA stenosis. Methods: We studied patients with isolated pontine infarcts recruited from a stroke registry. The patients with pontine infarction were divided into 2 groups based on the location of the lesion on magnetic resonance imaging as follows: paramedian pontine infarct (PPI) and lacunar pontine infarct (LPI). We compared the vascular findings and risk factors in the patients with the 2 types of infarcts. Using modified imaging criteria, we compared the following dolichoectatic components of the BA: (1) ectasia, (2) lateral displacement and (3) height. Results: There were 96 patients (45 women, 51 men). Thirty-five patients had PPI and 61 had LPI. Ectasia of the BA was more frequent in the PPI group than in the LPI group (31.4 vs. 11.5%; p = 0.016). Ectasia of the BA was associated with an elevated odds ratio in the patients with PPI (odds ratio 5.80, 95% CI 1.66–20.21) by multivariate analysis. Conclusion: Ectasia of the BA other than elongation or angulation appears to contribute to the occurrence of PPI. These findings may be helpful in predicting certain types of stroke.