Abstract
BACKGROUND: Acute intracranial occlusion of the internal carotid artery (ICA) can be distinguished into (a) occlusion of the terminal ICA, involving the proximal segments of the middle or anterior cerebral artery (ICA-L/-T) and (b) non-terminal intracranial occlusions of the ICA with patent circle of Willis (ICA-I). While patients with ICA-L/-T occlusion were included in all randomized controlled trials on endovascular therapy (EVT) in anterior large vessel occlusion, data on EVT in ICA-I occlusion is scarce. We thus aimed to evaluate effectiveness and safety of EVT in ICA-I occlusions in comparison to ICA-L/-T occlusions. METHODS: A large international multicentre cohort was searched for patients with intracranial ICA occlusion treated with EVT between 2014 and 2023. Patients were stratified by ICA occlusion pattern, differentiating ICA-I and ICA-L/-T occlusions. Baseline factors, technical (modified thrombolysis in cerebral infarction (mTICI) scale) and functional outcomes (modified Rankin scale [mRS] at 3 months) as well as rates of (symptomatic) intracranial hemorrhage ([s]ICH) were analyzed. RESULTS: Of 13,453 patients, 1825 (13.6%) had isolated ICA occlusion. ICA-occlusion pattern was ICA-I in 559 (4.2%) and ICA-L/-T in 1266 (9.4%) patients. Age (years: 74 vs 73), sex (female: 45.8% vs 49.0%) and pre-stroke functional independency (pre-mRS ⩽ 2: 89.9% vs 92.2%) did not differ between the groups. Stroke severity was lower in ICA-I patients (NIHSS at admission: 14 [7-19] vs 17 [13-21] points). EVT was similarly successful with respect to technical (mTICI2b/3: 76.1% (ICA-I) vs 76.6% (ICA-L/-T); aOR 1.01 [0.76-1.35]) and functional outcome (mRS ordinal shift cOR 1.01 [0.83-1.23] in adjusted analyses. Rates of ICH (18.9% vs 34.5%; aOR 0.47 [0.36-0.62] and sICH (4.7% vs 7.3%; aOR 0.58 [0.35-0.97] were lower in ICA-I patients. CONCLUSION: EVT might be performed safely and similarly successful in patients with ICA-I occlusions as in patients with ICA-L/-T occlusions.