Classic Vascular Compression: Trigeminal Neuralgia
This is a preview. Check to see if you have access to the full video. Check access
Hello, ladies and gentlemen. My name is Aaron Cohen. Thank you for joining us for the first series of videos related to microvascular decompression surgery for medical refractory, trigeminal neuralgia. Preoperative MRI, on this patient demonstrates a potentially a vascular loop against the left sided trigeminal nerve. You can see that the high resolution MRI, Allows a very detailed assessment of the anatomy in the region. This patient subsequently underwent a left sided, retromastoid craniotomy. Let's go ahead and review the relevant anatomy. Again, a left sided retromastoid craniotomy was completed. This is the tentorium at the edge of my arrow. This is the petrous bone, obviously the fifth cranial nerve and the vascular loop that is along the shoulder of the nerve. This is a typical classic neurovascular conflict in trigeminal neuralgia. Again, the most common form of vascular conflict or vascular compression on the nerve is along the medial shoulder of the nerve as demonstrated here. You could see the motor root of the trigeminal nerve, and again, the main sensory root of the nerve. We'll go ahead and start dissecting the nerve from the motor root. You can see that there could be additional branches hiding just anterior to the first one. These arachnoid membranes can be very thick, requiring meticulous microdissection to allow the vascular loop to be mobilized. Here you can see a true vascular loop that was pressing on the nerve at this location causing some discoloration of the nerve. This finding is very reassuring that the offending vessel has been found and addressed. It's important that the superior petrosal vein that can sometimes be here, could hide some of the vessels and really a meticulous examination and inspection in this area is important to avoid missing those vascular loops that could be potentially just anterior to the nerve and the upper portion of the shoulder. I do not generally use a fixed retractors. As you can see, dynamic retraction is used using the dissector in my left hand or right hand. And the superior petrosal vein is frequently not taken as it is unnecessary to do so using dynamic retraction techniques Here is further mobilization of artery to make sure it's completely moved away from their route into a zone of the trigeminal nerve. I use a Shredded Teflon and placed the Teflon just proximal on the nerve and push it distally to be able to mobilize the artery completely. Use of the Shredded Teflon in pieces allows a more efficient modeling of the implant to fit the area of the neurovascular conflict and prevents a delayed dislodgements of the implant. You can see the superior cerebellar artery branches under some spasm at this region. We'll go ahead and use a pattern soak gel foam to relieve the spasm. Further inspection around the nerve reveals no other compressed lesions. Here is the pattern soak gel foam. You can see that it's really important to look around the nerve completely 360 degrees. Even the one compressor vessel has been found. You still have to look around inferior and anterior aspect of the nerve to assure that the compression is adequately addressed. Here is another piece of Teflon that was placed. Again, you can see these pieces of Shredded Teflon are placed in the stepwise fashion and are pushed forward. This allows the entire cisternal segment of the nerve as was the root into its own to be decompressed. And this maneuver is important for optimizing postoperative pain freedom outcomes. Here you can see more panoramic view at the root enter a zone making sure there is no vessel along the route into a zone at the level of the brain stem. Here you can see that I was unable to find any further vessel to be mobilized. You can see the adequate amount of Teflon that was used to decompress the artery. I prevent using too much Teflon as Teflon granuloma could potentially be a source of recurrent pain. Here you can see a complete inspection around the nerve especially superiorly making sure that the loop is not contacting the brain stem at the level of the nerve.
Please login to post a comment.