Microsurgical Resection of a Ventral Pontine Cavernoma via Supratrigeminal Zone by Anterior Transpetrosal Approach: 2-Dimensional Operative Video.

Abstract

Brainstem cavernomas with recurrent bleeding and gradual neurological deterioration should be considered an indication for surgical treatment. However, surgery is challenging for cavernous hemangiomas located in the ventral part of the pons. In such cases, safe surgical access to the brainstem is limited and obtaining a good surgical field, regardless of the approach selected, is often difficult. Here, we show a 73-year-old man with a history of 3 episodes of intracranial bleeding associated with a cavernous hemangioma located in the right ventral pons. The hemangioma was removed via the supratrigeminal zone of the brainstem using an anterior transpetrosal approach (ATPA). ATPA was first described in 1985 for upper petroclival lesions by Kawase T.1 This approach requires epidural subtemporal procedures to expose the petrous apex adequately. The petrous apex must be totally resected and the dura of the temporal lobe and posterior fossa is then cut to ligate the superior petrosal sinus and tentorium. In this procedure, the most important things are to preserve the internal carotid artery (C2 segment) and greater superficial petrosal nerve (GSPN). To identify the GSPN, facial nerve integrity monitor (Medtronic Inc, Dublin, Ireland) is very useful. In the extradural bone removal, Sonopet Ultrasonic Aspirator (Stryker Ltd, Portage, Michigan) is a very excellent surgical tool for avoiding the injury of the internal carotid artery. As demonstrated by Cavalcanti DD2, ATPA is particularly useful for accessing lesions located in the upper ventral pons via the supratrigeminal zone because it provides a wide and shallow surgical field above the trigeminal nerve without requiring retraction of the cerebellum. We received written informed consent from the patient for this publication.