Comparison between intrasylvian and intracerebral hematoma associated with ruptured middle cerebral artery aneurysms: clinical implications, technical considerations, and outcome evaluation

Background: Subarachnoid hemorrhage (SAH) due to a middle cerebral artery (MCA) aneurysm rupture is often associated with an intracerebral hematoma (ICH) or intrasylvian hematoma (ISH). Methods: We reviewed 163 patients with ruptured MCA aneurysms associated with pure SAH or SAH plus ICH or ISH. The patients were first dichotomized according to the presence of a hematoma (ICH or ISH). Next, we performed a subgroup analysis comparing ICH versus ISH to explore their relationship with the most relevant demographic, clinical, and angioarchitectural features. Results: Overall, 85 patients (52%) had a pure SAH, and 78 (48%) had presented with an associated ICH or ISH. No significant differences were observed in the demographics or angioarchitectural features between the 2 groups. However, the Fisher grade and Hunt-Hess score were higher for the patients with hematomas. A good outcome was observed in a higher percentage of patients with pure SAH compared with those with an associated hematoma (76% vs. 44%), although the mortality rates were comparable. Age, Hunt-Hess score, and treatment-related complications were the main outcome predictors on multivariate analysis. Patients with ICH appeared worse clinically compared with those with ISH. We also found that older age, a higher Hunt-Hess score, larger aneurysms, decompressive craniectomy, and treatment-related complications were associated with poor outcomes among the patients with an ISH, but not an ICH, which appeared, per se, as a more severe clinical condition. Conclusions: Our study has confirmed that age, Hunt-Hess score, and treatment-related complications influence the outcome of patients with ruptured MCA aneurysms. However, in the subgroup analysis of patients with SAH associated with an ICH or ISH, only the Hunt-Hess score at onset appeared as an independent predictor of the outcome.