Abstract
Objectives: To investigate clinical and imaging predictors of short- and long-term outcomes in patients with posterior circulation stroke (PCS), with particular focus on infarct topography and ischemic burden. Methods: We conducted a retrospective multicenter observational study including 251 consecutive patients with acute PCS. All patients underwent CT angiography within 24 h and follow-up CT/MRI at 48-72 h. Clinical data, vascular risk factors, stroke severity (NIHSS), and functional outcome assessed by modified Rankin Scale (mRS), were collected. Short-term outcome was defined as mRS at discharge and long-term outcome as mRS at 3 months. Favorable outcome was defined as independence, graded as mRS 0-1. Imaging analysis included pc-ASPECTS, collateral scores, and quantitative ischemic volume assessment. Multivariable logistic regression was performed to identify independent predictors of outcome. Results: Among 251 patients, 105 (41.8%) had LVO. Patients with LVO presented with higher NIHSS scores, larger infarct volumes, and more frequent multiregional involvement. Basilar artery occlusion was associated with the most severe clinical and radiological profile. Infarct location, ischemic volume, baseline NIHSS, and pre-stroke mRS were independently associated with short-term outcome. For long-term outcome, age, infarct location, diabetes, and pre-stroke mRS remained significant predictors. LVO status and treatment variables were not independently associated with outcome. Conclusions: In PCS, outcome is primarily influenced by infarct topography and clinical factors rather than LVO status alone. Multiregional involvement and baseline disability are key determinants of prognosis. These findings underscore the need for PCS-specific prognostic models and highlight the importance of detailed imaging assessment beyond vessel occlusion.