Histopathologic evaluation of basilar artery atherosclerosis

There has been limited attention to pathological features of basilar artery atherosclerosis. It has been assumed that pathology of basilar artery atherosclerosis mimics that of other vascular beds.

To define the nature of the basilar artery atherosclerotic lesions, we analyzed postmortem intracranial artery samples from eight subjects with history of stroke.

Atherosclerotic lesions were present in 7/8 arteries examined, with a mean estimated stenosis of 34%. Lumen thrombus with a disrupted fibrous cap was seen in 1 lesion; the remaining 6 lesions revealed a thick fibrous cap. Neovascularity and calcification were seen in 1 lesion and mild to moderate inflammation was seen in 3 lesions. Necrotic core was present in 4/7 lesions, and was associated with plaque rupture in the only disrupted lesion.

Basilar artery atherosclerotic lesions were relatively benign in this series of patients presenting with stroke. While confirmation is needed with larger sample size, the relative paucity of neovascularity suggests a possibly distinctive histopathological profile.