Surgical resection of A giant ventral pontine cavernous malformation: Two-dimensional video

Abstract

Cavernous malformations (CM) in the ventral pons pose significant surgical challenges due to their deep anatomical location and complex neurovascular structures [1]. This report details the successful surgical management of a giant ventral pontine CM in a 38-year-old female exhibiting left-sided limb weakness (muscle strength Grade IV), and was approved by the ethics committee. Magnetic resonance imaging (MRI) findings indicated the CM extended from the pial surface predominantly towards the right side. Utilizing diffusion tensor imaging (DTI), we determined that the corticospinal tract was laterally positioned. Subsequently, and with patient consent, we decided to remove the CM via a trans-Sylvian approach instead of the traditional subtemporal approach. During surgery, after the right frontal-temporal craniotomy, we carefully dissected the Sylvian fissure and excised a portion of the uncus to enhance the exposure of the oculomotor nerve, thereby improving surgical efficiency within both the carotid-oculomotor and oculomotor-tentorial triangles [2], [3]. To alleviate tension on the oculomotor nerve, we carefully incised its overlying dura mater, minimizing intraoperative retraction injury. We employed piecemeal debulking and sharp dissection of the CM along the gliotic interface while preserving perforating arteries and protecting a notable developmental venous anomaly encountered during the procedure. Intraoperative endoscopy confirmed gross total resection, with stable electrophysiological monitoring maintained throughout the operation. Postoperatively, the patient experienced transient right oculomotor nerve palsy and left limb weakness (Grade III + ), both of which improved with rehabilitation at 3-month follow-up. This case underscores the complexities of ventral pontine CMs and the necessity for customized surgical strategies to achieve favorable outcomes.