Brainstem cavernous malformations resected via miniature craniotomies: technique and approach selection.

Brainstem cavernous malformations can cause devastating neurologic disability when they hemorrhage, which occurs at a higher rate in the brainstem than in other locations. Traditional access to these lesions requires a large craniotomy with extensive exposure and manipulation of vital structures. We present a case series of patients who underwent surgical resection of brainstem cavernous malformations using minimally invasive approaches at our institution from January 2012 to August 2014, all of whom had experienced at least one hemorrhage prior to presentation. Approach choice was determined by location of the cavernous malformation in relation to the brainstem surface. Resection occurred through our described standardized method. Postoperatively, there were three instances of transient neurologic symptoms, all of which resolved at time of last follow-up. All eight patients experienced neurologic improvement after surgery, with four patients showing no deficits at last follow-up. Approach selection rationale and technical nuances are presented on a case-by-case basis. With carefully planned keyhole approaches to cavernous malformations presenting to the brainstem surface, excellent results may be achieved without the necessity of larger conventional craniotomies. We believe the nuances presented may be of use to others in the surgical treatment of these lesions.