INTRODUCTION Early identification of intracranial atherosclerotic disease(ICAD) may influence management strategies in patients undergoing mechanical thrombectomy(MT). We have previously developed a scoring system for pre‐thrombectomy diagnosis of ICAD in the anterior circulation(Score‐ICAD‐AC) with satisfactory discrimination/calibration which we aim to evaluate in the setting of posterior circulation occlusions(Score‐ICAD‐PC). METHODS This was a retrospective analysis of prospectively maintained MT databases from 3 comprehensive stroke centers(CSC). All consecutive patients who underwent mechanical thrombectomy were assessed for eligibility and included if they had a posterior circulation occlusion (vertebrobasilar junction/basilar artery/posterior cerebral artery). ICAD was defined as in‐situ disease suspected to relate to ICAD identified by the treating neurointerventionist during thrombectomy. The diagnosis of ICAD‐related stroke was made when stenotic lesions involving the target vessel were unveiled during MT or when present at baseline leading to perfusion defect perceived to explain ischemic symptoms. Spasm, sub‐occlusive thrombus or other vasculopathic processes were not considered ICAD. Non‐ICAD controls included patients with posterior circulation LVO due to other etiologies within the same study period. Radiological data based on preprocedural non‐contrast CT and CTA. Score‐ICAD is a 20‐point scale: absence of atrial fibrillation(5‐points); vascular risk factor burden(1‐point) for each of hypertension, diabetes, smoking, and hyperlipidemia; multifocal single artery stenoses on CT angiography(3‐points); absence of territorial cortical infarct(3‐points).In the Score‐ICAD‐PC, presence of borderzone infarct(3‐points) was substituted for site of occlusion (Proximal Or Mid= vertebral V4 to pre‐SCA) (3‐points). Ipsilateral carotid siphon calcification (2‐points) was substituted by VBJ calcification (2‐points). Results Out of 3,171 thrombectomies performed during the study period, 283 patients with posterior circulation stroke were included(97 ICAD and 186 controls). Clinical characteristics, imaging features, laboratory results, procedural details, and functional outcomes are summarized in Table1. After application of the modified score‐ICAD to the posterior circulation cohort, the AUC was 83.9% (CI:0.79‐0.89; p‐value11, the test demonstrates high sensitivity (79.4%), comparing favorably with the Score‐ICAD‐AC (71%). A cutoff of >13 had specificity of 86.4%, comparable to the threshold of ≥12 for Score‐ICAD‐AC(90%). The optimized threshold by Youden Index (0.52) was 13.5 points, with 86.4% specificity/66% sensitivity. Conclusion In this multicenter study, the application of the previously validated scoring system (Score‐ICAD‐AC) to posterior circulation strokes led to satisfactory and comparable discriminatory performance. Further prospective studies are needed to externally validate this score and assess its clinical utility in guiding treatment decisions. image
Sayed et al. (Sat,) studied this question.