Introduction: Among patients with ischemic stroke, 3-17% are found to have at least one intracranial dolichoectatic artery. Atherosclerosis was previously thought to most commonly underlie abnormally dilated arteries, but recently the correlation of dolichoectasia with imaging markers of small vessel disease has suggested a shared underlying vascular process. Further clarification of this association is needed.
Hypothesis: Basilar artery dolichoectasia is more frequent in patients with lacunar infarctions in comparison to other stroke subtypes. Imaging markers of small vessel disease are associated with basilar artery dolichoectasia.
Methods: Among consecutive ischemic stroke admissions to a single medical center over three years, the 100 cases initially classified as lacunar stroke, and a randomly sample of 100 non-lacunar strokes cases were selected. For the present study, only patients with vascular imaging (MRA or CTA) were included resulting in a final cohort of 86 patients in the lacunar stroke group and 92 in the non-lacunar stroke group. Basilar artery ectasia and dolichosis were defined following Smoker’s criteria. MRIs were reviewed for the presence of old lacunar infarcts, deep cerebral microbleeds, enlarged perivascular spaces and moderate-to-severe white matter hyperintensities. These markers were added for estimating the total small vessel disease score ranging from 0 to 4 points.
Results: The mean age was 65.5±1.9 years (53.9% men). Basilar artery dolichoectasia was present in 29.1% of patients with lacunar infarctions and in 15.2% of non-lacunar strokes (p:0.04). The mean basilar artery diameter was significantly higher in patients with lacunar mechanism of stroke (3.87±1.04 mm versus 3.30 ±0.9 mm, p:0.0001). Patients with basilar artery dolichoectasia were more likely to have a small vessel disease score of 2 or higher than those without (p:<0.05).
Conclusions: Our results support a stronger link between dilative arteriopathy and small vessel disease than with other stroke subtypes. Basilar artery dolichoectasia and small vessel disease might have common triggers that activate a cascade of events resulting in the pathological changes characteristics of these conditions.