Objective: The goal of this study was to analyze the natural history of symptomatic brainstem cavernomas (medulla, pons, or midbrain) and outcome after surgical resection.
Methods: We retrospectively analyzed clinical data of all patients who presented to our institution with symptomatic brainstem cavernomas between 1995 and 2007 (n = 44).
Results: After a first neurological event, the median event-free interval was 2 years, with an annual event rate of 42%. After a second neurological event (new neurological deficit or significant worsening of the previous deficit), the median event-free interval was only 5 months, with a monthly event rate of 8%. After an observation period of up to 8 years, all patients ultimately underwent surgery. In 95% of the patients, surgery successfully prevented further events during a median follow-up period of 11 months (1 month-7 years; P < 0.001). The postoperative event rate was 5% per year in the first 2 years and 0% thereafter. In the multivariate analysis, only the preoperative modified Rankin scale score was predictive of the surgical outcome (odds ratio, 36.7; P = 0.015). The conditions of 2 patients (5%) were clinically worse compared with their preoperative conditions during the 1-year follow-up period; in one of these patients, this was caused by recurrent events. There was no mortality.
Conclusion: The event rate of symptomatic lesions seems to be high, particularly after recurrent events. Surgical morbidity can be low. Timely and complete surgical resection is recommended for symptomatic brainstem cavernomas to prevent patients' functional decline owing to recurrent events.