Risk Factors for Unfavorable Outcomes in Surgically Treated Brainstem Cavernous Malformations

OBJECTIVE: Brainstem cavernous malformations (BSCMs) account for up to 18% of all intracranial cavernous malformations. Due to their complex anatomic location, they represent a significant challenge for neurosurgeons. As such, the identification of risk factors associated with negative outcomes is of significant importance. We analyze a series of 50 cases of BSCMs treated surgically in order to identify risk factors for unfavorable outcomes. METHODS: Patients who underwent surgical resection of BSCM at our institution between 2000 and 2015 were retrospectively reviewed. Univariate and multivariable logistic regression models were used to identify predictors of unfavorable outcomes, defined as those with a modified Rankin score (mRs) of > 2. RESULTS: Fifty Latin American patients, with a mean age of 35.85 +/- 13.06 years, consisting of 29 females (58%) and 21 males (42%), underwent surgical resection. Mean modified Rankin Scale (mRs) score at admission was 2.6 +/- 1.05, and the mean BCSM size was 18.00 +/- 7.19 mm. The rate of gross total resection was 92%. Overall, 80% of patients showed improved or unchanged clinical status at the last follow-up period; however, only 58% of patients had a favorable outcome with a mean mRs of 2.33 +/- 1.136. Multivariable logistic binary regression identified hemorrhagic recurrence (P = 0.040), lower cranial nerve deficit (P = 0.019), and BSCMs > 15 mm in diameter (P = 0.006) as predictive factors for unfavorable surgical outcomes. CONCLUSION: BSCM size, compromise of lower cranial nerves, and hemorrhagic recurrence before surgery were identified as risk factors associated with unfavorable outcomes of surgically treated BSCMs in this cohort.