Petrosal approaches to brainstem cavernous malformations.

OBJECT: Although they provide excellent ventral and lateral exposure of the brainstem, petrosal approaches to brainstem cavernous malformations (CMs) are infrequently reported.

METHODS: The authors reviewed their experience with petrosal approaches to brainstem CMs in combination with a comprehensive review of the literature to elucidate resection rates, complication rates, and outcomes.

RESULTS: Including their own results, the authors found 65 cases in 20 reports of brainstem CMs treated with petrosal approaches. The specific approaches were posterior petrosal in 37 cases (57%), anterior petrosal in 17 (26%), extended posterior petrosal in 10 (15%), and a combined petrosal approach in 1 case (2%). For 50 cases in 16 reports with detailed outcome information, the overall complete resection rate was 90%, with early postoperative morbidity reported in 30% of cases and permanent morbidity in 14%. The rate of CSF leakage was 6%.

CONCLUSIONS: The versatile petrosal approaches to brainstem CMs are associated with good outcomes and an acceptable morbidity rate. More expansive lesions can be approached using a combination of the standard anterior and posterior petrosal approach, preserving hearing and avoiding the greater complication rates associated with extended posterior petrosal approaches.