A case report on differential diagnosis of internal carotid artery agenesis or occlusion

Abstract

Congenital internal carotid artery (ICA) agenesis is a rarely encountered abnormality. People with this abnormality usually have adequate collateral circulation and remain asymptomatic for many years. Sometimes, patients may present with pulsatile tinnitus, headache or blurred vision and rarely with ischemic stroke or subarachnoid hemorrhage. The diagnosis is usually made upon carotid artery Doppler ultrasonography or cervical/cranial magnetic resonance imaging performed for other reasons. On the other hand, it may be misdiagnosed as ICA occlusion in lack of attention. In this paper, we report a patient complaining of facial paresthesis referred to our center for invasive therapy due to left-sided ICA occlusion, who was then diagnosed as having ICA agenesis.