Intrasylvian hematoma caused by ruptured middle cerebral artery aneurysms predicts recovery from poor-grade subarachnoid hemorrhage

Abstract

Object Intrasylvian hematoma (ISH) is a subtype of intracranial hematoma caused by aneurysmal rupture and often presents with a poor initial neurological grade; it is not well studied. The aim of this study was to elucidate outcomes of aneurysmal subarachnoid hemorrhage (SAH) with ISH. Methods Data for 97 patients with poor-grade SAH (World Federation of Neurosurgical Societies Grade IV or V) were retrospectively analyzed from a single-center, prospective, observational cohort database. Ultra-early surgical clipping, removal of hematoma, external decompression for brain swelling, and prevention of vasospasm by cisternal irrigation with milrinone were combined as an aggressive treatment. Characteristics and clinical courses of SAH with ISH were identified. The authors also evaluated any correlations between poor admission-grade SAH and ISH with good functional outcome. Results Patients with poor admission-grade SAH and with ISH were more likely to have initial cerebral edema (p < 0.001, Mann-Whitney U-test), which significantly resolved over time (p < 0.001, Mann-Whitney U-test). These patients had a better chance of functional survival (modified Rankin Scale scores of 1-3; OR 5.75; 95% CI 1.36-24.3; p = 0.017) at 6 months after hospital discharge, after adjustment for potential confounders such as younger age and better initial neurological grade by multivariable analysis. Conclusions ISH predicted good functional recovery from poor-grade aneurysmal SAH.