Intra- and extracranial stenoses in TIA – Findings from the Aarhus TIA-study: A prospective population-based study

Background

Atherosclerotic stenoses of the intracranial arteries (ICAS) is associated with high risk of stroke after TIA. The prevalence of intracranial stenoses is considered to be low in Caucasians, however population-based data are lacking and only a minority of patients with acute TIA or stroke is evaluated for ICAS.

Methods

We prospectively examined the prevalence of stenoses of the pre- and intracerebral vessels using transcranial colour coded sonography (TCCS) in a population based cohort of all TIA patients in the community of Aarhus, Denmark in the period 1.3.2007–29.2.2008.

Results

The TIA cohort included 203 patients fulfilling the diagnostic criteria for TIA. We examined 195 patients with extra- and intracranial TCCD.

Any stenoses and symptomatic ICAS was found in 12.3% and 8.2%, respectively. The stenoses were located in the intracranial internal carotid artery in 3.6% and 3.1%, anterior cerebral artery in 0.5% and 0%, middle cerebral artery in 4.6% and 2.6%, intracranial vertebral artery in 2.1% and 1.5%, and in the basilar artery in 1.5% and 1.5%, respectively. In comparison, we found any stenoses and symptomatic stenoses in the extracranial carotid artery in 14.4% and 10.8%, and the extracranial vertebral artery in 5.6% and 2.1% of the patients, respectively. Carotid occlusion was found in 3.6%, combined extra- and intracranial stenoses in 4.9%.

Conclusion

The prevalence of ICAS was in this population-based TIA cohort of Caucasians comparable with the prevalence of carotid stenoses. Systematic evaluation for intracranial stenoses should be considered in all patients with acute ischemic cerebrovascular disease.