Occipital Interhemispheric Transtentorial Approach for Microsurgical Resection of a Ruptured Vermian Arteriovenous Malformation: Three-Dimensional Operative Video.

Cerebellar arteriovenous malformations (AVMs) are associated with higher risk of rupture compared with cerebral AVMs.1 Microsurgical resection of a ruptured AVM, measuring 3 cm in its largest dimension, within the cerebellar vermis and right parasagittal cerebellar lobe is demonstrated in Video 1. Cerebral angiography showed major supply from both superior cerebellar arteries and minor supply from a right anterior inferior cerebellar artery-posterior inferior cerebellar artery variant. Venous drainage was through a single ectatic vermian vein draining toward the torcula. Intraoperatively, a second, thrombosed, draining vein connected to the vein of Galen was identified. A right interhemispheric occipital transtentorial approach was elected over the supracerebellar infratentorial approach for early access to the superior cerebellar artery feeding arteries and for an orthogonal rather than a tangential view. The patient was positioned in an ipsilateral lateral position with the head turned 45° toward the floor allowing for gravity retraction of the ipsilateral occipital lobe. An external ventricular drain was also inserted to allow for further relaxation of the occipital lobe. Under neuronavigation guidance, the tentorium was opened allowing immediate visualization of the AVM with early control of the superior cerebellar artery arterial feeders. The AVM was removed using standard microsurgical technique, and hematoma was evacuated. Postoperative cerebral angiography demonstrated no AVM residual. The patient was discharged to a rehabilitation institute with minor residual cerebellar deficits. The patient provided written informed consent for the procedure, video recording, and publication.