(AS2) Comparison of Neurological Outcome of Surgically Treated Brainstem Cavernous Malformations Following Single or Multiple Hemorrhages

Introduction: The timing of surgery in patients with hemorrhagic brainstem cavernous malformations (BSCM) remains controversial. The present study aims to compare outcomes of surgically treated BSCM patients who had a history of a single or multiple hemorrhages at initial referral.

Methods: 557 surgically treated patients with hemorrhagic BSCM were retrospectively analyzed. The relative change in the Modified Rankin Scale (mRS) score at the last clinical follow-up examination compared to baseline was analyzed as primary outcome, with mRS score worsening defined as a mRS score change >0. Friedman’s test with Dunn’s multiple comparison test was performed to analyze the change in the mRS score at the postoperative and final follow-up examination compared to the preoperative evaluation. McNemar test was performed to test for the change in motor, sensory and cranial nerve deficits pre- and postoperatively.

Results: After a median follow-up time of 14 months, 78% of patients with a single hemorrhage (281/557 (50.4%)) and 79% of patients with multiple hemorrhages (276/557 (49.6%)) had favorable outcomes (mRS≤2). The neurological status of 83% of patients with a single hemorrhage and 86% with multiple hemorrhages was unchanged or improved (p=0.438). In contrast to patients with multiple hemorrhages (p=0.003), patients with a single hemorrhage did not experience significant postoperative neurological worsening (p=0.168). At the final follow-up evaluation, the mRS score of patients with single and multiple hemorrhages had improved significantly compared to the preoperative examination (p=0.011 and p=0.018, respectively). Whereas patients with multiple hemorrhages experienced a significant postoperative increase in motor deficits (p < 0.001), patients with a single hemorrhage only had more sensory deficits (p=0.015) while the percentage of cranial nerve and motor deficits did not increase significantly.

Conclusion : In specialized centers, surgical treatment may be a justifiable treatment option for BSCM patients following a single hemorrhagic event to prevent future rehemorrhage and subsequent neurological worsening.