Abstract

Dr. Anagha Joshi, Dr. Ashwini Sankhe, Dr Arvind Borde* and Dr Civona Gomes

ABSTRACT

Agenesis of the internal carotid artery (ICA) is a rare congenital anomaly. Most of the patients are asymptomatic and it is usually discovered incidentally by computed tomography (CT) or magnetic resonance imaging (MRI). While collateral blood flow may allow these patients to remain asymptomatic, there is close association of the intra-cranial aneurysms and subarachnoid hemorrhage with ICA agenesis. Hence, recognition of this anomaly has important implications during planned carotid or transsphenoidal surgery, in thromboembolic disease, and in the surveillance and detection of associated cerebral aneurysms. We present 3 cases of absent ICA, suspected due to absent bony carotid canal on non-contrast CT (bone window settings). Out of these, only 1 patient had previous episode of hemiplegia (CVA), while the other two had unrelated symptoms. These patients were further evaluated by CT cerebral angiography, which revealed ICA agenesis with various patterns of collateral circulation. One of the patients had a co-existing developmental venous anomaly (DVA). None of our patient had sub-arachnoid hemorrhage.