Subclavian steal syndrome unmasked by large-vessel occlusion stroke: a case of persistent trigeminal artery

Abstract

A 52-year-old woman was admitted with acute onset of right hemispheric carotid syndrome. Computed tomography angiography revealed a right intracranial internal carotid artery occlusion and a thrombus at the aortic arch occluding the left subclavian artery. She had no palpable left radial pulse. No vertebral territory ischemia was documented. Angiography demonstrated a persistent primary trigeminal artery and a saccular aneurysm at the communicating segment of the left internal carotid artery (Figure 1). The persistent primary trigeminal artery, a rare primitive embryonic circulation remnant, connects the carotid and vertebrobasilar systems.