Relationship of chronic occlusion site of internal carotid artery to the outcome of recanalization

Abstract

Objective To investigate the relationship of chronic occlusion site of internal carotid artery (ICA) to the outcome of recanalization. Methods The patients with chronic symptomatic occlusion of ICA who were treated by endovascular revascularization or hybrid surgery at Cerebrovascular Division of Interventional Therapy Center, Henan Provincial People's Hospital from May 2015 to May 2017 were retrospectively reviewed. According to the location of ICA occlusion, the patients were divided into 2 types: Type Ⅰ occlusion and Type Ⅱ occlusion. Type Ⅰ occlusion was located from cervical segment to the cavernous segment and below, whereas Type Ⅱ occlusion was originated from cervical segment to the clinoidal segment and beyond.Comparison was conducted on the rates of technical success and re-occlusion after operation between Type Ⅰ occlusion and Type Ⅱ occlusion. Results Forty-five patients with chronic symptomatic ICA occlusion had a total technical success rate of 91.1% (41/45). The technical success rate was 100.0% (25/25) in Type Ⅰ occlusion and 80.0% (16/20) in Type Ⅱ occlusion, and the difference was statistically significant (χ2=5.040, P=0.025). Among the 41 patients who were successfully recanalized, 40 acquired clinical follow-up with a median of 12 months(range: 4-36 months). The rate of re-occlusion was 0% (0/25) in Type Ⅰ occlusion and 26.7% (4/15) in Type Ⅱ occlusion with statistical difference (χ2=8.821, P=0.003). Conclusions Patients with Type Ⅰ occlusion seem to have high technical success rate and low re-occlusion rate, which can be treated to improve the outcome. Type Ⅱ occlusive patients have relatively low technical success rate whereas high re-occlusion rate, which should be comprehensively evaluated before operation. Key words: Carotid artery, internal; Arterial occlusive diseases; Endovascular procedures; Hybrid surgery; Treatment outcome