Outcome Prediction in Brainstem Cavernoma

Objectives: Despite the recent surge in the literature concerning brainstem cavernoma; an optimal management approach to this challenging lesion is still lacking. The complex location poses a challenge in terms of working angle, identifying the safe surgical corridors and unpredictable postoperative outcomes. In the present study, we intend to summarize our center’s experience in treatment of the brainstem cavernoma, and we attempt to determine the clinical parameters that might predict the outcomes in these patients.

Methods: We conducted a retrospective review of 59 patients with radiological and histologically confirmed brainstem cavernomas diagnosed between 2000 and 2012. Surgical treatment was offered to all patients who had: (1) a symptomatic lesion presenting with acute presentation or the progressive neurological deficits caused by cavernoma mass effect, (2) lesions that were superficial and within 2-3 mm of the brainstem pial surface, (3) lesions that were deep although can be approached by a safe trajectory, and (4) MR imaging showing acute, subacute, or delayed hemorrhage. All but five patients were deemed amenable to surgical resection. Complete resection was attempted in all cavernomas and was achieved in 58/59 patients. A modified Rankin scale (mRS) score, dichotomized as mRS 0-2 (favorable outcome) or mRS 3-6 (unfavorable outcome), was employed for neurological status assessment. The association of the various clinical parameters to the different brainstem locations was evaluated. Predictors of the surgical outcomes were analyzed using univariate and multivariate regression statistics.

Results: The mean age of 32 female and 27 male patients was 34.3 years. The differences in cavernoma size, conservative treatment, and complications were significantly associated with the various locations of the cavernoma in the brainstem. Clinical parameters including age at presentation (P = 0.029, OR = 0.061, CI = 0.009-0.414), location of cavernoma (P = 0.02, OR = 4.15, CI = 1.2-14.04), favorable preoperative mRS (P = 0.004, OR = 0.058, CI—0.009-0.343), and surgical timing (P = 0.05, OR = 0.087, CI = 0.07-1.03) were found to be independent predictors of the favorable surgical outcomes. Mean long-term follow-up of 42.9 months was available in 31/59 (52.5%). The mean cavernoma size was 22.5 mm; small size (<10 mm) at presentation was associated with favorable outcomes at long-term follow-up (univariate analysis, P = 0.041, adjusted R2 = 0.471). Preoperative mRS (P = 0.039), location of the cavernoma (P = 0.034) in the brainstem, and MRI types (P = 0.041) were the predictors of good surgical outcomes at long-term follow-up.

Conclusion: Favorable surgical outcomes can be anticipated in brainstem cavernoma patients with early age at presentation, pontine location of the cavernoma, favorable preoperative mRS, and those undergoing early surgery. The outcomes at long-term follow-up were associated with location of the cavernoma in the brainstem, MRI types at presentation, size of the cavernoma, and the preoperative mRS.