Cavernous malformation of the ventral midbrain successfully removed via a transsylvian-transpeduncular approach: case report.

A 37-year-old woman presented with a rare cavernous malformation of the ventral midbrain with brainstem hemorrhage manifesting as sudden onset of headache and vomiting. The lesion was removed successfully through a transsylvian approach and a medial peduncular route. Postoperatively, her oculomotor nerve paresis worsened temporarily, but diplopia disappeared 2 months after surgery. We recommend the transsylvian-transpeduncular approach if the lesion is located in the ventral midbrain and faces the ventral surface of the brainstem, because of the effective access with minimal neurological deficits.