Name:
10.3171/2022.1.FOCVID21248
Description:
10.3171/2022.1.FOCVID21248
Thumbnail URL:
https://cadmoremediastorage.blob.core.windows.net/0e80d212-dd41-4223-8c29-72d8cd44cd01/videoscrubberimages/Scrubber_70.jpg
Duration:
T00H08M06S
Embed URL:
https://stream.cadmore.media/player/0e80d212-dd41-4223-8c29-72d8cd44cd01
Content URL:
https://cadmoreoriginalmedia.blob.core.windows.net/0e80d212-dd41-4223-8c29-72d8cd44cd01/21-248.mp4?sv=2019-02-02&sr=c&sig=VV0nwXfMzBe9gP24XoM%2FREa2OCOxdc8XQzrR3kpuFhk%3D&st=2025-02-05T14%3A08%3A25Z&se=2025-02-05T16%3A13%3A25Z&sp=r
Upload Date:
2022-02-14T00:00:00.0000000
Transcript:
Language: EN.
Segment:0 .
[MUSIC PLAYING]
SPEAKER 1: This is the illustrative case of a 44-year-old female patient that presented with symptoms of hydrocephalus and difficulty swallowing. On imaging, she had this very large petroclival meningioma with severe brainstem compression and dilated ventricles. We can see the vascular supply coming from the tentorial branches and the severe compression of the midbrain.
SPEAKER 1: We planned a combined transpetrosal approach with a middle fossa dissection posterior pedicle flap for reconstruction. We performed a large craniotomy with burr holes on both sides of the transverse sinus. These anatomy dissections illustrate the craniotomy that was performed, exposing the transverse sinus. And then we'll drill the mastoid. We'll also perform our middle fossa approach, with the goal of exposing Meckel's cave and the trigeminal nerve branches in an extradural fashion.
SPEAKER 1: This allowed us to expose the cavernous sinus back to the tentorium and Meckel's cave, and join these across the tentorium, to join the posterior fossa and medial cranial fossa components of this tumor to maximize our tumor access. But now in theory, the craniotomy has been performed already. And now we're performing the mastoidectomy. This is a retrolabyrinthine approach, with hearing preservation intention.
SPEAKER 1: The sigmoid sinus has been skeletonized. This is our neurotology team, Professor Jackler performing the approach. We're now in the middle fossa. Neurosurgery is doing this part. That's V3, and we identify the middle meningeal artery that we transect and we coagulate. Now, we peel the middle cranial fossa from anterior to posterior, identify the anterior wall of the cavernous sinus, then back to the petrous apex, to identify the greater petrosal superficial nerve and V3.
SPEAKER 1: Now we carefully dissect the trigeminal nerve back to Meckel's cave. We then perform our anterior petrosectomy, starting anterior and medial. You can also use an ultrasonic aspirator to facilitate this more narrowing drilling. And now we go to the area of the internal auditory canal. Again, our neurotomy colleagues are now opening the internal auditory canal and roofing it.
SPEAKER 1: And this provides extra exposure, stimulating the facial nerve. We're now proceeding with the dural opening, and starting in the posterior cranial fossa. And then we'll extend these into the cisterns, where we can see similar nature of complex and the tumor. In this case, we are fortunate to have a quite soft meningioma, which is very favorable. The tentorium is being now clipped at the level of the superior petrosal sinus, and then we can start our transection of the tentorium.
SPEAKER 1: We have opened the dura along the base of the medial temporal lobe, or base of the medial cranial fossa. There is some tumor above the tentorium that we are now debulking. We can see the edge of the tentorium, the medial edge. We're looking for the fourth nerve, but it's been very displaced by the tumor, so it's not at the usual location, as we will see later.
SPEAKER 1: We've nearly accessed the tumor, that as we said, is soft in consistency. However, it is quite vascular. We follow the trigeminal nerve, and now we're opening Meckel's cave here, with a right-angle knife. I follow the dura along the trigeminal nerve to open the ring of Meckel's cave, and this frees up the trigeminal nerve, and allows me to access Meckel's cave.
SPEAKER 1: And all the dura of Meckel's cave is now being removed, because it's involved with the tumor. This is the roof of Meckel's cave that is being removed. And this widens my exposure to start working along the pitroclival edge, along the clivus, where I expect to find the sixth nerve or the space, anterior inferiorly, by the tumor. I'm working up posteriorly along the trigeminal nerve, between V and VII-VIII complex.
SPEAKER 1: We can follow the trigeminal nerve all the way to the pons. And with careful microsurgical dissection technique, we can respect the neurovascular structures. We're working at both V now, between V and III. And now we see all the lower nerves dissected inferiorly, VII, VIII, and then V. In our different windows in between cranial nerves, there are venous access to the deeper location of the tumor.
SPEAKER 1: We see that's the tumor that is medial to V. And this is working between V and the medial temporal lobe. Cranial nerve III and VI are going to be identified medially. We are going to see cranial nerve VI, abducens nerve, displaced by the tumor. And again, we progress with careful microsurgical dissection. We identify the sixth nerve origin at the brainstem.
SPEAKER 1: This is great because we can then try to follow it, detach it from the tumor capsule, and follow it all the way to the dural entry point into Dorello's canal. This portion of the tumor is the highest portion of the tumor, toward the third cranial nerve and compressing the uncus. We finally see the basilar artery. We saw the anterior inferior cerebellar artery, and our next point of dissection is going to be along the basilar artery, and the brainstem, in particular, the midbrain.
SPEAKER 1: We perform further debulking to facilitate mobilization of the tumor. And again, this is the portion of the tumor that is highest; it requires some temporal lobe retraction. We can finally identify the third nerve, medially displaced, superior and medial. Fourth nerve is being identified finally, also displaced, along with the third nerve, superior and medial.
SPEAKER 1: We keep dissecting along the third nerve, and we see the tumor attachment to the dura of the posterior clinoid. That's again the basilar artery, and we've carefully dissected this tumor, behind this large perforating vessel. We can see the superior cerebellar artery partially encased in tumor. We can debulk it and do careful microsurgical dissection to dissect the tumor.
SPEAKER 1: All these basilar artery branches is an area of surgery that we have to be extremely careful about because of the risk of pontine perforator stroke. We can finally see the midbrain, very compressed, flattened by the tumor. We can see the third nerve with a PCA above, and as we saw before, the SCA below. Now finally freed up from tumor. There's the sixth nerve, coagulates really-- stimulates really well at the end of surgery, and a near-complete tumor resection.
SPEAKER 1: The reconstruction was performed with a large fat graft and with that posterior pedicle flap along the mastoid. It's important to put a large fat graft to occupy all the empty space and prevent pseudomeningioceles and CSF leaks postop. And as you see, a near- complete tumor resection, with perhaps very minimal residual on the posterior clinoid process. Thank you.
SPEAKER 1:
Form Title Download
Form Title Bookmark
Form Title Share
Form Title Cite
