This video reviews techniques for a sectional Posterior Callosal or a Splenial AVM through the posterior interhemispheric approach. This is a 58 year old female who present with a sudden Thunderclap headache and on CT scan and was diagnosed with intraventricular hemorrhage. CT angiogram demonstrate the location of the malformation along the posterior Corpus Callosum. The main feeding vessels are from the distal pericallosal arteries and a tearing vein, joins the vein of Galen. You can see some of the perforating and feeding branches also from the posterior cerebral artery. This is the angiographic architecture of this malformation. Again those large feeding vessels from the interior cerebral artery, joining the draining vein to the vein of Galen. And this is the angioarchitecture through the vertebral injection, a lateral view. Which demonstrates the feeding vessels from the posterior circulation along the posterior aspect of the malformation. I did not feel embolization would be very helpful in this AVM as the main feeding pedicles can reach through the interhemispheric approach early on during the procedure. Therefore, resection was undertaken through the interhemispheric approach without preoperative embolization. This is the position of the patient on the operating table in the lateral position. Patient underwent placement over the external ventricular drain at the time of her initial admission by one of my colleagues. You can see the head is turned toward the floor, 45 degrees, fixed in a skull clamp. Here's the parietal bossing. Using Stealth navigation and the incision was marked. This is the sagittal suture, mark with it. Shorter incision and a linear incision should be quite adequate to reach this lesion, which is quite deep. Following performance of the craniotomy, you can see the durus' opened, based over the Supercycle sinus. This is the left side, which was down in this case. This is the right side, the main feeding vessels who are from the left anterior cerebral artery and therefore the left side was chosen in. Also the hematoma within the parenchyma that you can see here being reached was within the medial aspect of the posterior left Pryor lope. You can see some CSF, means that the hematoma communicated with the interventicular space. As the hematoma was evacuated, you can see some of it feeding vessels to the AVM. Upon removal of the interproximal hematoma along the posterior inferior aspect of the medial parietal lobe the brain is more relaxed. Now I can go ahead and find the feeding vessels to the malformation. Again, these are those large, distal pericallosal feeding pedicles to the malformation that is located primarily here. I'm skeletonizing these vessels to identify them as feeding vessels by standards or transitional vessels. Here is the large feeding pedicle, here is other pedicles along the precuneus, here is the ADVIL through the Corpus callosum. The feeding pedicles are pursued to love the malformation and coagulate and cut. They can be quite thick and may sometimes require a clip application before they acquire coagulation in transection. Here's the edge of the malformation. Here are the pedicles that most likely only feed the malformation. I went ahead and start to skeletonize the malformation. However, I ended up causing more bleeding in this area that you will see momentarily. The bleeding was not easily controllable. At that juncture I decided to sacrifice these feeding vessels that were going to the malformation. Here's the bleeding, somewhat very difficult to control. Most likely related to the supply from these feeding vessels that are much larger in that area, at the tip of my arrow. You see by coagulating and sacrificing the flow through these branches. The bleeding is rarely under control. Emphasizing the importance of early devascularization for managing these high-flow large malformations. I'll go ahead and place it. Small permanent aneurysm clip on the distal feeding pedicle, of the particle sole artery. Now some of the feeding vessels over the precuneus and the medial hemisphere are being skeletonized and sacrificed. This is followed by white matter dissection. Here's more de-magnified view of the malformation that is being more defined. Now, here is another feeding pedicle over the posterior medial parietal lobe. Some cortical incision to disconnect the malformation. Here is the bulk of the malformation. Here is the area along the white matter dissection. The callosum is here. I should be able to find the hematoma cavity shortly. Here are the deep, white matter feeders of the callosum. I redirected my attention toward the hematoma cavity and here is the atrium of the lateral ventricle on the ipsilateral side. Here is a plexo-feeding vessel that will be coagulating and cut. Here's the choroid plexus under my suction. Bleeding can be quite problematic from these plexus segments. Now the bleeding was controlled. There I'll go ahead and re-explore that hematoma cavity and connect it to my initial resection cavity more anteriorly. To further circum-dissect on the malformation, here's the posterior aspect of the malformation. Here's the falx cerebelli joining the tentorium. You can see it relatively. No more draining vein there. Not very arterialized. Here is the hematoma cavity. Here's moving more posterially, along the malformation and disconnecting the cortical connections. Now coming back to the anterior-inferior aspect of the malformation where the deep white matter feeders are being disconnected. These could be quite problematic and difficult to control. Require significant amount of patience. And the tumor is being ruled posterially toward its pedicle which is the draining vein, at the area of the vein of Galen. Here's the tip of the ventriclustomy catheter that was placed somewhat or posteriorly than usual. Came very close to the night of Southern malformation. Here is now disconnecting the malformation from contralateral medial parietal cortical feeders. These cortical feeders are rarely, coagulable. You saw a moment ago a peek view of the contralateral atrium. Here's the draining vein. Here's some of the feeding vessels that are deeper from the posterior cerebral artery, at the more inferior aspect of the malformation. These feeders are carefully isolated and after their identity as feeding vessels is confirmed, these vessels are also coagulated and cut. Now we'll come on the other side of AVM toward the right side, and disconnect some of the feeding vessels originating from the contralateral hemisphere. Obviously the draining vein is carefully protected. Here's the right side of the malformation that has been disconnected. Here is the ventriculostomic catheter that is mobilized away from the malformation. I'll go ahead and continue dissecting the malformation more on its right side. The malformation looks quite relaxed at this time, which means that most of the feeding vessels have been excluded. Here again, is entry into that contralateral atrium or the right atrium. Here's the malformation that is quite circumscribed and circum-dissected by now. The hemorrhoid aspect of the malformation that is being disconnected and the malformation is more ruled posteriorly toward its draining vein pedicle. Most of the AVM by now is disconnected. Now, here is coming along the pedicle of the malformation more posteriorly where the draining main is quite clear. There's often an arterial branch very closely related to the large draining vein. I'm going to dissect around the draining vein to assure myself that there's no large normal vein, that is intimately related to the abnormal draining vein. Here's the process of dissection of the draining vein. I'm not finding any other normal vein draining dice-falx structures. Here again another large arterial feeder closely related to the draining vein of the malformation. Here's the primary vein, joining the vein of Galen. I look around the malformation, it is quite disconnected. Here's the draining vein right at its juncture connection or attachment to the nidus of the malformation. Another feeding vessel. Now the draining vein is being sacrificed. One may place a clip across the draining vein before coagulating it and disconnecting it. In this case, the draining vein is quite collapsed and I felt its coagulation would most likely be safe. Here's cutting the vein across its cross-section in stages and using bipolar coagulation to collapse the lumen. The AVM is now quite disconnected. The nidus is removed. Here's the final view of the dissection cavity. The postoperative CT angiogram demonstrate that complete removal of the malformation without any complicating features. Thank you.
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