Transtentorial Approach for Parahippocampal Gyrus Arteriovenous Malformation Resection: 3-Dimensional Operative Video

Abstract

Medial temporal basal arteriovenous malformations (AVMs) have complex anatomy. They usually drain to the basal vein of Rosenthal, and arterial feeders can arise from the anterior choroidal artery and its branches, or from the posterior cerebral artery. If the AVM is more posterior in the parahippocampal gyrus, there is a predominance of arterial feeders arising from P2P or P3 segments of the posterior cerebral artery. As posterior AVMs are difficult to reach using anterior approaches, the supracerebellar transtentorial approach provides a direct pathway to the malformation, allowing better visualization and exposure of the vascular anatomy. In this video, we present a 29-yr-old woman with a left parahippocampal AVM with P2P arterial feeders and Rosenthal basal vein drainage. The patient had three months of moderate headache and two abrupt seizures before admission. Emergency computed tomography showed intraventricular hemorrhage. Magnetic resonance imaging and cerebral angiography revealed an AVM located in the parahippocampal gyrus, posterior to pulvinar thalamus. The patient underwent microsurgical treatment in semi-sitting position using a supracerebellar and infratentorial approach with transtentorial resection. The AVM was completely removed, and the patient recovered without neurological deficits. The authors present a 3-dimensional video of the microsurgical steps required to perform a transtentorial approach for AVM resection in the parahippocampal gyrus. The patient signed the Institutional Consent Form, which allows the use of his/her images and videos for any type of medical publications in conferences and/or scientific articles.

Clip retraction of the tentorium: application of a novel technique for tentorial retraction during supracerebellar transtentorial approaches

“…Previous studies have characterized the use of either SCTT or occipital transtentorial approaches for the microsurgical resection of meningiomas, 4,6,16 CMs, 8-10 epidermoid cysts, 17 and other pathologic conditions. 11,12,18,19 Compared with transcortical routes, transtentorial approaches provide excellent anatomical exposure without traversal of eloquent cortex or retraction of parenchyma. However, a limitation of these transtentorial approaches is the narrow corridor through the tentorium, which may hinder visualization or limit the dexterity of the surgeon.…”

“…Recently, supracerebellar transtentorial (SCTT) approaches have become a popular option for treatment of a variety of pathologic conditions in the medial and basal temporal and occipital lobes. [4][5][6] Lesions such as meningiomas, 7 gliomas, cavernous malformations (CMs), [8][9][10] and arteriovenous malformations 11,12 have been removed through posterior approaches through the tentorium, often with the use of the sitting position and gravity retraction of the cerebellum to widen the supracerebellar space and extend the upward reach beyond the tentorium. We and others have found this strategy useful for the treatment of thalamic pathologic entities that abut the posterior-inferior surface of the pulvinar.…”

The art of combining neuroanatomy and microsurgical skills in modern neurosurgery

“…The patient underwent microsurgical treatment in a semi-sitting position, and the approach chosen was a supracerebellar infratentorial with transtentorial resection. Figure 8 details the correlation between a cadaveric specimen and the steps during the surgery ( 24 , 25 ). As we can see, training the exposure in the laboratory before in a real patient let the neurosurgeon learn how to position the hands, open the skin, the extension the craniotomy, the space generated during the supracerebellar infratentorial approach, which structures the neurosurgeon will find after opening the tentorium, and which instruments he needs to improve the treatment of the condition, in this case, an AVM.…”

The Technique of Limited Quadrangular Lobe Removal to Safely Resect a Quadrigeminal Plate Arteriovenous Malformation: 2-Dimensional Operative Video

“…The high risk of hemorrhage eloquence and increased susceptibility to adverse radiation effects restricts the management of such cases to experienced centers. 1,2 The latency associated with radiosurgery, poor results from embolization as primary therapy all make surgery a favored option in experience hands. 3 A good understanding of the anatomy, arterial supply, and venous drainage of this region is required to safely manage pathology located here.…”