January 21, 2016
Let's review some of the basic strategies for resection of Petrotentorial Meningiomas. This is a 32 year old female who presented with left sided facial weakness and gait imbalance. And it was found to have a Meningioma primarily based over the area of middle fossa herniating around the area of the tentorium and effecting part of the petroclival junction. You can see the tumor does cause some mass effect on the brain stem. There's also some evidence of edema, around the area of the temporal lobe. The approaches to this tumor are quite varied. I felt that the largest portion of tumor is centered over the subtemporal space. And therefore a Middle Fossa Approached was used with transection of the tentorium to remove as much of the tumor as possible within the posterior fossa. After completion of it, middle fossa approach to dural was open. Currently in fashion, you can see the temporal lobe. You can see the area of the optic nerve and carotid artery or the anterior fossa. Next, I direct my attention posteriorly over the posterior aspect of the tentorium or the portion of the tumor that was herniating tore the posterior fossa was a parent. After identifying the fourth nerve, a part of the tentorium that was overlying the residual tumor and a posterior fossa was transected. You can see the fourth Nerve is being mobilized to, I can use the Infra trochlear window for a section of the tumor. As suture was placed at the edge of the tentorium to expand the operative space. Here's this superior part of the cerebellum or its tentorial surface. Some of the branches of this superior cerebellar artery were apparent. Further transection of the tentorium allowed expanded exposure. You can see the tumor within the posterior fossa was subsequently mobilized into our initial resection cavity and angled dissectors were also used to further deliver the tumor into the supratentorial space. You can see the fourth nerve. You can see both the infra and supra trochlear windows were utilized. Here's additional portion of the tumor within the posterior fossa, not brainstem appears well decompressed. No additional tumor is easily apparent. It is a small piece of tumor more anteriorly that is being also removed. Part of the tumor that was invading the cavernous sinus was left intact. Postoperative MRI demonstrates reasonable resection of the tumor, which is outside the cavernous sinus. The portion of the tumor that was within the cavernous sinus was left behind, and this patient had improvement of her preoperative symptoms. The learning points about this case is the use of modified forms of basic cranial approaches for resection of complex skull-based tumors. In this case, rather than using a more radical skull-based Osteotomy and traditional Middle Fossa Approach was augmented using transection of the tentorium. Thank you.
Please login to post a comment.