Influencing Factors And Classification Of Recanalization Treatment For Chronic Internal Carotid Artery Long-segment Occlusion

Background and PurposeChronic internal carotid artery occlusion is one of the important causes of ischemic stroke.If the occluded carotid artery was recanalization,blood flow perfusion could improve and the incidence of long-term ischemic stroke could reduce.This study retrospectively analyzed the data of patients with chronic internal carotid artery long-segment occlusion treated by endovascular intervention and hybrid surgery,to explore the related factors affecting the outcome of recanalization of chronic internal carotid artery long-segment occlusion,and try to put forward the classification and scoring that could guide the recanalization treatment.Analysis the correlation between the score and clinical outcomesMethodA retrospective analysis was made of 53 patients with chronic internal carotid artery long-segment occlusion who underwent endovascular intervention and hybrid surgery from May2015 to July 2018.According to the location of occlusion,the internal carotid artery was divided into type I occlusion(the beginning of occlusion was in the carotid segment,the distal end of occlusion was in the cavernous sinus segment and below)and type II occlusion(the beginning of occlusion was in the carotid segment,and the distal end of occlusion was in the clinoid process segment and above).According to the location of the plaque,the internal carotid artery was divided into type A occlusion(the proximal end of the internal carotid artery)and type B occlusion(the distal end of the internal carotid artery).There are four subtypes,type I A occlusion,type I B occlusion,type II A occlusion and type II B occlusion.The technical success rate,the incidence rate of perioperative complications and the rate of follow-up re-occlusion were recorded,and the differences of recanalization treatment results among different types were compared.Results1.Forty-seven(88.7%)of 53 patients with internal carotid artery long segment occlusion were successfully recanalization.The technical success rate of type I occlusion was 26/26(type I A:22/22;type I B:4/4).The technical success rate of type II occlusion was 68.8%(21/27),of which90.9%(10/11)and 68.8%(11/16)were for type II A and type II B occlusion respectively.The technical success rate of type I occlusion was higher than that of type II with statistical significance(?~2=6.515,P=0.034).The technical success rate of type A occlusion patients(97%)was higher than that of type B occlusion(75%).The difference was significant(?~2=5.987,P=0.046).There was no statistical difference between type I A and type I B occlusion,also type II A and type II B occlusion.2.There are three perioperative complications occurred.In type I occlusion,internal carotid artery cavernous sinus fistula occurred in one patients.In type II occlusion,thrombus displacement occurred in 1 case during operation and acute occlusion in the other case after operation.There was no significant difference in the incidence of perioperative complications between type I and type II occlusion.3.Forty-six successful patients were followed up by imaging,with an average follow-up of 12months and 6 re-occlusion.The re-occlusion rate of type I occlusion patients was 0/25(type I A:21/21;type I B:4/4);and that of type II occlusion patients was 28.5%(6/21).The re-occlusion rates of type II A and type II B occlusion patients were 10%(1/10)and 45.5%(5/11),respectively.The re-occlusion rate of type II occlusion was significantly higher than that of type I occlusion(?~2=8.214,P=0.015).The re-occlusion rate of type B occlusion was 33.3%(5/15),which was higher than that of type A 3.2%(1/31),the difference was statistically significant(?~2=8.079,P=0.018).There was no significant difference between type I A and type I B occlusion,type II A and type II B occlusion in follow-up re-occlusion rate.And no ischemic stroke or death occurred during the follow-up period.4.The segment-plaque score predicts clinical efficacy with high accuracy.Patients with score2-4 have a high success rate and low re-occlusion rate.ConclusionsIn this study,we found that the patients with distal occlusion located at cavernous sinus segment or below had a higher success rate and a lower long-term re-occlusion rate than patients with distal occlusion located at clinoid process segment or above.The segmental-plaque score is accurate in predicting the technical success rate and re-occlusion rate.