Ct-angiography in assessment of critical occlusive carotid artery disease

Abstract

Occlusive carotid artery disease is still one of the major causes of ischemic stroke in the world. Progression of severe carotid stenosis may lead to critical stenosis and vascular occlusion. Nevertheless, there is still no pure definition of the concept of critical occlusive carotid artery disease. To define the role of CT-angiography in assessment of critical occlusive carotid artery disease. We analyzed data of 405 patients who underwent preoperative precise assessment of carotid arteries and subsequent surgical treatment for the period from 2016 to 2019. Contrast-enhanced CT-angiography (Philips Ict scanner, 256 slices) was made after previous ultrasound. Contrast agent injection rate was 4-5 ml/sec. CT angiography data were assessed according to a specialized protocol. Critical occlusive carotid artery disease was observed in 128 (31.6%) cases including critical stenosis (24.94%), near-occlusion (5.92%) and local occlusion (0.74%). Critical stenosis was characterized by local narrowing ≥90% and normal diameter of distal arterial segment. In case of near-occlusion, local critical stenosis was accompanied by narrowing of distal arterial segment. In case of local occlusion, distal collateral supply of internal carotid artery occurred through atypically originating ascending pharyngeal artery. Patients with near-occlusion and local occlusion of internal carotid artery had no signs of ICA hypoplasia and intracranial stenoses. All elements of circle of Willis were observed in 70% of patients. State of distal segment of internal carotid artery can be considered as a differential diagnostic criterion for critical occlusive carotid disease variants. CT-angiography provides all necessary data and can be recommended for precise preoperative assessment.