Background/Objectives: Subarachnoid hemorrhage (SAH) is frequently complicated by cerebral vasospasm (VS). Clazosentan reduces VS, and fasudil hydrochloride hydrate (Fasudil) is widely used for VS prevention in Japan. However, the benefit of adding Fasudil to clazosentan remains unclear. We investigated whether adjunctive Fasudil was associated with VS-related and functional outcomes in clazosentan-treated aneurysmal SAH. Methods: We retrospectively analyzed data from the multicenter “Database of Cohort Study for Outcome of SAH in Japan,” collected from 2020 to 2024. Patients with aneurysmal SAH who underwent surgical clipping or endovascular coiling within 4 days of onset and completed 14 days of clazosentan treatment were included. Outcomes were compared between clazosentan plus Fasudil and clazosentan alone. Multivariable logistic regression assessed factors associated with angiographic vasospasm (AVS), cerebral infarction, and poor functional outcome (modified Rankin Scale 3–6) at discharge and 6 months. Results: Among 341 patients, 100 (29.3%) received adjunctive Fasudil and 241 (70.7%) clazosentan alone. AVS occurred in 58/329 (17.6%), cerebral infarction in 58/327 (17.7%), poor functional outcome at discharge in 142/341 (41.6%), and poor functional outcome at 6 months in 82/325 (25.2%). Adjunctive Fasudil was independently associated with higher odds of AVS (adjusted odds ratio [aOR] 2.41, 95% confidence interval [CI] 1.21–4.81), cerebral infarction (aOR 2.10, 95% CI 1.08–4.09), and poor 6-month outcome (aOR 2.88, 95% CI 1.08–7.71), but not with poor functional outcome at discharge (aOR 1.37, 95% CI 0.62–3.03). Conclusions: In clazosentan-treated aneurysmal SAH, adjunctive Fasudil use was not associated with additional benefit and was associated with higher odds of AVS, cerebral infarction, and poor functional outcome at 6 months.

Background/Objectives: Despite high sensitivity in deep learning models for identifying candidate locations of unruptured cerebral aneurysms (UCAs), excessive false-positive (FP) findings and insufficient characterization of their anatomical distribution remain barriers to clinical integration. We evaluated a multi-stage deep learning framework for reducing anatomy-specific FPs in TOF-MRA-based UCA screening. Methods: This retrospective multicenter study analyzed TOF-MRA images from 404 scans across seven institutions. A baseline model (Model-A) was compared with an updated model (Model-B) incorporating a secondary cluster-filtering algorithm. Reference standards were established by expert reviewers. Aneurysm-wise sensitivity was compared using McNemar’s test, FPs per case using the Wilcoxon signed-rank test, and FP distributions by vascular location. Results: Aneurysm-wise sensitivity was 94.3% (231/245) for Model-A and 93.9% (230/245) for Model-B, with 1.16 and 0.879 FPs per case, respectively, representing a significant 24% FP reduction (p < 0.001). Per-aneurysm sensitivity did not differ significantly (McNemar’s test, p = 1.00). Model-B suppressed mimics in the internal carotid artery (ICA) and middle cerebral artery (MCA). Aneurysms were most frequent in the ICA (29%) and MCA (22%). Setting Model-A FPs as 100%, ICA and MCA accounted for 47.1% and 11.3% in Model-A and decreased to 34.5% and 7.7% in Model-B. In an exploratory regional analysis with Holm adjustment, FP reductions remained significant in the ICA (adjusted p < 0.001) and MCA (adjusted p = 0.003). Conclusions: A secondary cluster-filtering algorithm reduced FP candidate findings by 24% with similar sensitivity point estimates (paired difference −0.4 percentage points, 95% CI −3.1 to +2.1). Region-specific error analysis revealed the anatomical dependency of FP reduction. The impact on reading workflow and patient outcomes requires prospective evaluation.