Objective To explore the safety and feasibility of mechanical thrombectomy as the first-line endovascular strategy in patients with non-acute symptomatic long-segment internal carotid artery occlusion(ICAO)undergoing revascularization.Methods This study retrospectively and consecutively enrolled non-acute symptomatic long-segment ICAO patients treated in the Department of Neurology,First Hospital of Jilin University,between January 2019 and August 2023,with mechanical thrombectomy as the preferred endovascular modality.Baseline and clinical data were collected,including sex,age,stroke-related risk factors(hypertension,diabetes,dyslipidemia,coronary artery disease,prior stroke,smoking and alcohol use history),admission National Institutes of Health stroke scale(NIHSS)score,pre-operative modified Rankin scale(mRS)score,time from last symptom onset to femoral puncture,time from imaging confirmation to femoral puncture,high-resolution MRI,right-sided ICAO,stump morphology(absent,tapered,flat/blunt,irregular),distal backfilling patterns(above ophthalmic segment,cavernous/clinoid segment,below cavernous segment),pathogenesis(atherosclerosis,dissection),types of anesthesia(local,general),procedure time(time frame from femoral puncture to recanalization or final angiography),site of the original occlusion in successfully recanalized cases,surgical techniques(aspiration+balloon angioplasty,aspiration+balloon angioplasty+stent-retriever thrombectomy,aspiration+balloon angioplasty+stent placement,aspiration+balloon angioplasty+stent-retriever thrombectomy+stent placement),stent placement(yes/no),number of stents implanted,and number of cases with retrieved thrombus,observed indicators.Observed indicators including ratio of technical successful recanalization(immediately post-procedure most severely stenosed site stenosis rate＜50%,expanded thrombolysis in cerebral infarction[eTICI]grade≥2c),intraoperative complications(distal embolization,symptomatic intracranial hemorrhage,arterial perforation)rate,perioperative mortality rate,30-day stroke recurrence,and 90-day mRS score.Compare the baseline data,clinical data and observational indicators of the patients with successful and unsuccessful recanalization.Base on the original occlusion site,successfully recanalized patients were subclassified into isolated extracranial,isolated intracranial,and tandem lesions patients,and their baseline characteristics and observation indicators were compared.Results(1)A total of 65 patients were enrolled(57 men,8 women;age 39-80 years;median 59[52,65]years)in this study.Technical success was achieved in 52cases(80%).Perioperative complications occurred in 4 patients(6.2%),with 3 distal embolization cases(4.6%),1(1.5%)developed symptomatic intracranial hemorrhage,and no arterial perforations were observed.There was no perioperative mortality.The 30-day stroke recurrence rate was 7.7%(5/65).90-day mRS scores ranged from 0 to 4,with a median of 1.0(0.0,1.5).(2)Baseline and clinical characteristics as well as outcome indicators did not differ significantly between patients with successful versus unsuccessful recanalization in the cohort undergoing mechanical thrombectomy for non-acute symptomatic long-segment intracranial carotid artery occlusion(all P＞0.05).(3)Among successfully recanalized patients,17(32.7%)had isolated extracranial lesions,18(34.6%)had isolated intracranial lesions,and 17(32.7%)had tandem lesions.All cases in the extracranial lesions group had original lesion site at the origin of internal carotid artery(C1,17/17).The intracranial group most often had orginal lesion sites at the C4 segment(9/18),whereas tandem lesions predominantly involved C1 plus C4-C5(16/17).Among the three groups,patients with isolated intracranial lesions were younger(57[48,61]years vs.60[52,64],63[58,69]years,P=0.050),and had a lower proportion of right-sided ICAO(4/18 vs.11/17 vs.11/17,P=0.032),while patients with tandem lesions required a greater number of stents(2.0[1.0,2.0]vs.1.0[1.0,1.5],1.0[0.8,2.0],P=0.013).Significant differences were observed in the proportion of patients with retrieved thrombus decreased progressively from patients with isolated extracranial,isolated intracranial to tandem lesions(17/17 vs.17/18 vs.12/17,P=0.024).No significant differences were observed among lesion-site groups with respect to medical history,stump morphology,distal retrograde flow,procedural technique,procedure duration,anesthesia method,or outcome indicators(all P＞0.05).Conclusions This study suggested that utilizing mechanical thrombectomy as the first-line endovascular therapy for non-acute symptomatic long-segment ICAO is safe and feasible.The original occlusive sites of non-acute symptomatic long-segment ICAO predominantly involve the cervical origin and the cavernous segment of the internal carotid artery.The conclusions of this study require further validation.

Objective To explore the safety and feasibility of mechanical thrombectomy as the first-line endovascular strategy in patients with non-acute symptomatic long-segment internal carotid artery occlusion(ICAO)undergoing revascularization.Methods This study retrospectively and consecutively enrolled non-acute symptomatic long-segment ICAO patients treated in the Department of Neurology,First Hospital of Jilin University,between January 2019 and August 2023,with mechanical thrombectomy as the preferred endovascular modality.Baseline and clinical data were collected,including sex,age,stroke-related risk factors(hypertension,diabetes,dyslipidemia,coronary artery disease,prior stroke,smoking and alcohol use history),admission National Institutes of Health stroke scale(NIHSS)score,pre-operative modified Rankin scale(mRS)score,time from last symptom onset to femoral puncture,time from imaging confirmation to femoral puncture,high-resolution MRI,right-sided ICAO,stump morphology(absent,tapered,flat/blunt,irregular),distal backfilling patterns(above ophthalmic segment,cavernous/clinoid segment,below cavernous segment),pathogenesis(atherosclerosis,dissection),types of anesthesia(local,general),procedure time(time frame from femoral puncture to recanalization or final angiography),site of the original occlusion in successfully recanalized cases,surgical techniques(aspiration+balloon angioplasty,aspiration+balloon angioplasty+stent-retriever thrombectomy,aspiration+balloon angioplasty+stent placement,aspiration+balloon angioplasty+stent-retriever thrombectomy+stent placement),stent placement(yes/no),number of stents implanted,and number of cases with retrieved thrombus,observed indicators.Observed indicators including ratio of technical successful recanalization(immediately post-procedure most severely stenosed site stenosis rate＜50%,expanded thrombolysis in cerebral infarction[eTICI]grade≥2c),intraoperative complications(distal embolization,symptomatic intracranial hemorrhage,arterial perforation)rate,perioperative mortality rate,30-day stroke recurrence,and 90-day mRS score.Compare the baseline data,clinical data and observational indicators of the patients with successful and unsuccessful recanalization.Base on the original occlusion site,successfully recanalized patients were subclassified into isolated extracranial,isolated intracranial,and tandem lesions patients,and their baseline characteristics and observation indicators were compared.Results(1)A total of 65 patients were enrolled(57 men,8 women;age 39-80 years;median 59[52,65]years)in this study.Technical success was achieved in 52cases(80%).Perioperative complications occurred in 4 patients(6.2%),with 3 distal embolization cases(4.6%),1(1.5%)developed symptomatic intracranial hemorrhage,and no arterial perforations were observed.There was no perioperative mortality.The 30-day stroke recurrence rate was 7.7%(5/65).90-day mRS scores ranged from 0 to 4,with a median of 1.0(0.0,1.5).(2)Baseline and clinical characteristics as well as outcome indicators did not differ significantly between patients with successful versus unsuccessful recanalization in the cohort undergoing mechanical thrombectomy for non-acute symptomatic long-segment intracranial carotid artery occlusion(all P＞0.05).(3)Among successfully recanalized patients,17(32.7%)had isolated extracranial lesions,18(34.6%)had isolated intracranial lesions,and 17(32.7%)had tandem lesions.All cases in the extracranial lesions group had original lesion site at the origin of internal carotid artery(C1,17/17).The intracranial group most often had orginal lesion sites at the C4 segment(9/18),whereas tandem lesions predominantly involved C1 plus C4-C5(16/17).Among the three groups,patients with isolated intracranial lesions were younger(57[48,61]years vs.60[52,64],63[58,69]years,P=0.050),and had a lower proportion of right-sided ICAO(4/18 vs.11/17 vs.11/17,P=0.032),while patients with tandem lesions required a greater number of stents(2.0[1.0,2.0]vs.1.0[1.0,1.5],1.0[0.8,2.0],P=0.013).Significant differences were observed in the proportion of patients with retrieved thrombus decreased progressively from patients with isolated extracranial,isolated intracranial to tandem lesions(17/17 vs.17/18 vs.12/17,P=0.024).No significant differences were observed among lesion-site groups with respect to medical history,stump morphology,distal retrograde flow,procedural technique,procedure duration,anesthesia method,or outcome indicators(all P＞0.05).Conclusions This study suggested that utilizing mechanical thrombectomy as the first-line endovascular therapy for non-acute symptomatic long-segment ICAO is safe and feasible.The original occlusive sites of non-acute symptomatic long-segment ICAO predominantly involve the cervical origin and the cavernous segment of the internal carotid artery.The conclusions of this study require further validation.