Gravity-Dependent Supine Position for the Lateral Supracerebellar Infratentorial Approach: An Alternative to the Prone and Sitting Positions: Operative Nuance.

Abstract

The supracerebellar infratentorial (SCIT) approach has been used for a variety of intracranial pathologies. Positioning has traditionally involved the sitting, lateral, or prone position. The sitting position allows gravity retraction of the cerebellum, with less cerebellar swelling and venous congestion compared with the prone position. There is less need for cerebellar retraction away from the tentorium with the sitting position compared with the prone and lateral positions. However, the sitting position involves disadvantages related to surgeon comfort and fatigue in protracted cases, as well as possible venous air emboli. To describe an operative technique of gravity-dependent supine (GDS) positioning to avoid certain drawbacks of sitting, lateral, and prone positions for the lateral SCIT approach. We present this positioning technique in 2 illustrative cases using the GDS approach. The first patient underwent surgical resection of a right cerebellar arteriovenous malformation that drained superiorly with the draining vein adjacent to the tentorium after a ventricular/subarachnoid hemorrhage. The second patient underwent surgical resection of a brainstem cavernous malformation in the left pontomesencephalic region with the GDS supracerebellar approach. Postoperative imaging demonstrated complete resection in both patients. There were no perioperative complications related to positioning or the surgical resections postoperatively, with an uneventful hospital course in both cases. The GDS lateral SCIT approach allows natural cerebellar relaxation via gravity without the need for lumbar drainage and is a novel, straightforward operative technique with inherent advantages over the prone, lateral decubitus, and sitting positions.