Transcript

- Colleagues and friends, thank you for joining us for another session of The Virtual Operating Room. Our guest today is Dr. Amir Dehdashti from Northwell Neurosurgery. He's a dear friend, really a master surgeon. He's going to talk to us about management of intraoperative complication, most likely the critical topic that is often overlooked. Amir is also the fellowship director for the CAST-approved fellowship at Northwell Neurosurgery for skull base and cerebrovascular surgery. Amir, I really appreciate you joining us today. Managing these intraoperative complications define the best of us, and how we manage complications really determine how the patient does. It's sometimes, or I'd say most of the time, it's not just the complication that determines the outcome, but how the surgeon reacts to the complication. Does the surgeon keep their composure and designs a very calculated plan? Or does the person have a knee-jerk reaction and tries to just get out of the complication without thinking about it? I've always said when you have a bad complication, such as an intraoperative rupture, it's best to just take a deep breath, think about it, but do not do the first knee-jerk reaction. So I think those are the critical aspects of intraoperative management of complications, and I'd love to learn from you. And so let's go ahead and get started. Thank you.

- Thank you very much, Aaron, and I'm honored to be invited again on your platform. And I have to say that what you have created over the past few years is one of the best, if not the best, way for any neurosurgeon, and that would include anyone from trainees, from medical students, residents, chief residents, fellows, junior and senior attending, to learn from it. This is a tremendous effort you're putting into this. I think the whole neurosurgery should be grateful to you for doing this. And I know the amount of work you have put into this and what we can learn from it. I have personally watched many, many, many of your sessions. And I'm honored to be one of the faculty here and talk about the topic that, as you mentioned, is not a comfortable topic to talk about because showing things that were not expected to happen, showing things that maybe were expected, but not to that extent. And I'm focusing on talking about management of intraoperative complications. It's not postoperative. It's really what happens during the surgery. And we'll focus on that. And I have to say, because I have a significant cerebral bypass practice, many of the cases that I show have bypass included in it because this is one of the surgery that a lot of unpredictable things can happen. So that's just a notice about that part, I think the preparation for surgery is one of the important thing to do before contemplating a potential intraoperative complication. I think if the preparation for surgery is correct, and that includes analysis and the indication and prehearsing and rehearsing the surgical steps. The day of the surgery, specifically, when you're going for the surgery, showing up with confidence. Reviewing the surgical step with the team, and this includes everyone, including the scrub nurse. And at the end, you have to be prepared for unexpected. So if you have this setup in mind, you will really try to decrease the unexpected events during the surgery, or, for the same matter, the intraoperative complication. Having said that, there is no way that someone who is doing complex intracranial microsurgery, cerebrovascular and skull base, can live a career of doing complex cases without having intraoperative complication. It's a given. It's a part of the game. And actually, I have to say it's what makes us even becoming better because we have to learn how to deal with that and how to be better the next time. Now, the complications. Obviously, most fearful complication in neurosurgery is bleeding, especially when you're working in deep locations. Vessel injury or vessel occlusion, nerve injury, damage to eloquent cortex and hematoma, intraoperative hematoma. Again, this is focused on intraoperative complications. So these are the type of complications that can happen, and I'm going to focus on the most significant ones and take it from there. The complications could be expected. Usually, they expect events like, let's say, a ruptured aneurysm, an intraoperative rupture, usually are preventable. However, they can lead to complications. It could be errors, and human errors are possible, and obviously, we want to minimize that, but that can lead to complications. These are the part that are preventable easily or easier. But they have unexpected events, and these are usually bad luck. For instance, usual findings and unusual finding on surgery. Suddenly, you see something that you did not interpret as such or you did not expect, and that change the decision-making and that, depending on what you decide to do, can lead to a complication. Or unusual events, that's the worst. That's the worst in the sense that it's an event that was not calculated and happens, and this is probably very highly likely to lead to complication if it's not dealt with appropriately. If you look at this chart of competence, and I think at the level that we are talking about, intraoperative complications, I think all of us that, we get to this kind of situation, obviously, we have passed these steps of going from unconscious incompetence to a unconscious competence. And I think the best situation for dealing with intraoperative major complication is to be at that level of unconscious competence. That you try to deal with something that you never expected, you never knew that that's going to happen, but you are able to deal with it. So this is what we have to get to. And that level of unconscious competence is not a status quo. I see myself, that every day, I have to be better. Every year, I have to be better than the year before. So that level of unconscious competence, it's not a achievement. It's a continuous progression. And that is basically what you need to deal with intraoperative complications, especially those that are unexpected, I think these six elements in surgeries are very important for microneurosurgery. We need to have the passion. They look for excellence. Surgery should be elegant, and the elegance of a surgery is an embodiment of the personal behaviors, the habits and mannerism. Surgery should be effortless. And we need to have resilience during surgeries. Some surgeries are very difficult, very long, tough. And we need to be persistent. Some strategies might not work. We cannot stop. We have to find a strategy, we have to change the tactic or technique to make it work. So these six things together are very important to make us a successful surgeon and to be able to deal with complications. And most important is that when we have a complication, the most important thing is that, the Latin word, we should not succumb to it. This is a patient with a vestibular schwannoma, large vestibular schwannoma, grade IVb Hannover. And a 27-year-old, facial weakness already. So this patient already had a facial weakness that made the surgery, in terms of results of facial nerve, more difficult because when we start with a facial weakness, the risk of having a permanent facial weakness is higher. And I was going for a complete resection for this tumor. That was my initial strategy, to operate on all vestibular schwannoma to try to get as much maximum as possible, total resection. Especially 27-year-old patient. And this is the patient. Surgery done in the sitting position. You can see here is the PICA. Behind the tumor, this is the loop of the PICA. So we debulk the tumor in the sitting position. Advantage of surgery in the sitting position is that the blood is all going down without the need for constant use of suction. So here, bimanual dissection is done around the nerve. The tumor is being debulked. And I identify the facial nerve at the brainstem and continue the debulking of the tumor. And trying to find the cores of the facial nerve here, above the tumor. This is obviously after several hours of surgery. The tumor has been resected. You can see the facial nerve very nicely up there. And I continued to separate from the brainstem. Have good exposure of the facial nerve and good response to monitoring. But at some point here, I lose the monitoring, and I see what happened. And suddenly, I realize the facial nerve has been cut unintentionally. But fortunately, I have the two end. So I use the sural nerve and I go ahead and, doing the same setting, sural nerve was not prepped, but we prepped it, get the sural nerve and suture to the proximal part of the nerve and to the distal part of the nerve. And this took about a year for patient to have, at best, that would be a grade III House-Brackmann weakness. So this is postop. Patient didn't have hearing, but obviously, the weakness, complete paralysis, improved to grade III, the best that we could do in that setting. And that actually, after having another patient like this when I lost the facial nerve, I changed my strategies after operating on hundreds of acoustic neuroma to go for a near-total resection, where we leave a little bit of epineurium around the facial nerve to not have this injury to the facial nerve. So this is a lesson that I learned from my own experience, and also how to deal with a direct nerve injury during an operation. This patient is a sphenoid wing meningioma that, as you can see here, encasing the MCA vessels. So we go with the preoperative angio, and possible embolization was done. There is a little bit of a, you can see the anterior temporal branch and the MCA that were encasing the tumor. Some embolization was done, relatively minimal. The patient's going for surgery. This is a right-sided approach. You can see the MCA encased in the tumor. And here, we are separating the tumor. I'm operating here with, obviously looking to skeletonize the MCA vessels that are completely stuck in the tumor, and then at the same time, debulk the tumor. Pretty vascularized tumor, as you can see, despite embolization. And the surgery is going smoothly. Nothing is too complicated here. You can see here, this vessel looks like it's, this vessel seems that it's going to the tumor, but it's not really going to the tumor. There is just this branch that is going to the tumor. This vessel is just the script around the edges of the tumor. So this vessel can be taken. And then the rest of it will be preserved. But then, when I continue, there is another vessel here, this one, that I cannot find any continuity on the other side. And I intentionally take this vessel, thinking that this is one of the vessels that is really a PL vessel going to the tumor. And it didn't look that big to me, so I didn't think that that's important. But when I rolled the tumor, and interestingly, during this time, I lose the monitoring. And the monitoring team say, "Well, we have lost this motor evoked potential om the left side." And I see here, realize that the other side of the vessel is on the other side of the tumor, and I misinterpreted that. So basically, I cut one of the MCA branches, which is a very, very obvious error, error of judgment in terms of decision-making on the continuity of the vessel. So what we do here is that I have the proximal vessel here and I have the distal vessel. I need to create room to make them more mobile and redundant, and cuts the tip that was coagulated and then bring them back together. So at this point, I don't have any motor evoked potential. The patient is suffering from ischemia, and the vessel also going a little bit into spasm. But then we bring these two together with the 10-0 sutures, a end-to-end bypass, as quick as I can. You have no luxury of time here. The patient is suffering from lack of motor evoked potential. We increase the blood pressure at the same time. And I also give the patient heparin. I don't want the patient to have it thrombose into the distal MCA that I have cut. So I give 3,000 units of heparin to the patient. And we do this and we open that, and the vessel is back to functioning. And fortunately, the motor evoked potential came back within minutes of reestablishment of flow. And then we go back and remove the rest of the tumor. And the rest was uneventful with this vessel, as you can see on the surface of the Sylvian fissure, the MCA, and the patient did fine, with no neurological deficit, and postop imaging showing a complete resection of the tumor and preservation of the MCA bifurcation. Now, there is another situation where we deal with this, foramen magnum meningioma, with vertebral artery encased by the tumor. You can look at this coronal pictures and see how the vertebral artery is inside this tumor, making it a complex foramen magnum meningioma. So this is a far lateral approach. This is the part that the has been drilled a little bit, to give us a flat lateral access to this skull base. And we work on the lateral aspect here. We go in, this is the vertebral artery entrance. We can see the vertebral artery here. Going in toward the dura, and the dura is open in a linear fashion. And we identify the tumor. I use gel foam with lidocaine on the 11th cranial nerve to make it desensitized. Otherwise, the shoulder will move all the time, especially for these tumors. You can see this is nine and 10. We devascularized the base of the tumor. This is the vertebral artery. You can see the PICA coming out of it, with all the perforators to the brainstem from the vertebral artery. And this is the tumor. Really looked like a giant partially thrombosed aneurysm, with the vessel really going into it. So we remove, we try to debulk the tumor and separate the tumor away from the vert. Pretty significant bleeding from the tumor itself that needs to be coagulated at time. And this is the hypoglossal nerve going over the vertebral artery. At this point, I decided to take the vert because I thought it's impossible to remove this tumor in this young patient without sacrificing the vert. This is the facial and AICA perforators here. There is a co-dominant vert on the other side, so I didn't think that taking a vert distal to PICA and before the VB junction will be a problem. So I put a clip on the proximal, and I'm looking for the distal verts to be able to clip the distal vert, and then take the whole tumor out, with the vert in between. So at this point, monitoring is all stable, despite the vertebral artery being clamped. And now I identify the distal vert, which is pretty difficult because really deep and on the more medial side. The clip is positioned on the distal vertebral artery. And at this point, I realized, after two minutes, that the monitoring is gone. So we had a right-side decrease in motor evoked potential and even somatosensory evoked. Pretty dramatic. So I took the clip off, and this time, I put the clip closer to the first clip. And I was wondering what could possibly be the cause of decrease in monitoring? And when we dissect further, you find this medullary perforator that is stuck into the tumor, and that is going to the brainstem. So this was a major finding that did not allow me to do a complete resection. I had to leave tumors around that medullary perforators and put the clip on the vert in a way that you see. So the vert was sacrificed below that perforator, with some tumor attached to the perforator. This patient woke up with some weakness of the right side that were new, but no stroke on the MRI. And you can see this is the postop resection, and she recovered from the right side, but she had lower cranial nerve deficit, necessitating temporary PEG for six weeks. This is a situation that is also a complicated situation for neurosurgeons, a vertebrobasilar insufficiency in a patient who had multiple stroke in the brainstem, and in the cerebellum as well. Very dizzy patient, some weakness, double vision. And you can see there were strokes in the center of the brainstem. Significant vertebral stenosis bilaterally. This was tried by my endovascular colleague to be stented. It was not possible. And the only option that I could see for this patient. And if you can look at the NOVA, you can see that the results are very worrisome, with extremely low flow in the posterior fossa, in the basilar artery, in the PCA. And in unusual situation, I would like to use the occipital artery as a donor for vertebrobasilar circulation. This is based on a paper published by our Chinese colleagues, using occipital artery to extradural vertebral artery. But here, the problem was that the problem was also intracranial. So we felt, I felt that even if you do that, intracranial stenosis would still be a problem. So here, we go to use the occipital artery and connect that to the AICA. And you can see here that the AICA, on this low right picture, you can see the AICA is the only vessel, the last vessel visible on the basilar artery. And we go and explore the AICA through an extended retrosigmoid. We harvest the occipital artery here. And by harvesting the occipital artery, which I would like to harvest from proximal to distal, the same way that we do a harvest of the STA. Now we go to the retrosigmoid fissure. We identify the AICA. This AICA, you have to dissect it out, out of the horizontal fissure, and it's a very, very good vessel to be bypassed on, if there is an indication. Now, the first complication here, the occipital artery, I cut, and there is no good flow in it. So I lost patency in the occipital artery. So at this point, that's the first complication. Although at the beginning was good. So we cut the occipital artery at its origin, so there is a good flow at the origin. And now we have to harvest radial artery because you see there's a very good flow at the origin. So we get a radial artery, and radial artery comes into the game, and I connect the radial artery to the AICA. And two clips are positioned above the lower cranial nerve and below seven and eight. And I use, for the radial artery, I like to use 9-0 sutures because 10-0 would not hold in the radial artery, and do a combination of running and interrupted sutures. This is radial artery connected to the AICA here. I open the clip on AICA and there is good flow going through the graft, to the anastomosis, just up to the clip. Now we come up. So this is the difficult part of the bypass. Now we are happy, we come here and do the more easier part of the bypass, doing an end-to-end bypass to occipital artery, connect that together. Open the graft. Initially, it looks okay. There is good flow going through it. Cut the last sutures. But within about a minute, the bypass loses patency. So I'll check and see that this is how to manage, salvage a bypass failure. There is good flow coming to it. When I clamp distally, I see that the problem is from proximal. So the distal flow from the graft in the brain is good, but not the proximal flow. There is a problem with that proximal occipital artery. So I try to salvage. Pass irrigation, heparin, saline inside, resuture twice, but still, the same thing happens. And that's the reason that we have to go and redo the bypass again, revision the proximal segment. There is a problem with that part, the very proximal part of the occipital artery, that I had to cut, shorten the graft, go back and do basically a third anastomosis here. We see there is an excellent flow proximally, and do the bypass again. So that's an example of perseverance. You know, this is we cannot leave the room until we make this bypass work because we can identify what is the problem. So we just have to interrogate. And finally, after the last effort, we have the bypass open, going to the AICA. And the follow-up at three months shows that there is a 32 mL per minute of flow through this graft going in. This patient's symptoms of dizziness, vertigo and gait instability improved, with no new stroke. This is another situation of perseverance in a patient who had prior occlusion of the carotid artery, with initially well-tolerated, but recently becoming symptomatic with TIAs. And the reason for that is on this NOVA MRA, you can see the flow is only 16 mL per minute on the right MCA. So most likely, this patient initially tolerated that occlusion, but gradually, over time, became flow dependent. And you can see that that's a significant discrepancy. So we went in for a IMax MCA bypass here to read the radial artery graft. So this is an MCA that I picked for the graft. And that's, based on what we see here, this MCA seems to me, at the beginning, to me, that's a good target and I perform a regular end-to-side bypass on it. Seemed to be uneventful. And when I connect this graft, when I open the graft, there is no flow coming back up to the clip. So the bypass, the vessel itself is open, but the graft doesn't get the flow back. So I could not figure out why this is happening. So that's why I gave up on that vessel. There was no change in the monitoring. I found a better vessel, so you can see here, and that was connected to that MCA. And now I'm connect it to the IMax. And the IMax works, everything looks perfect at the beginning, but within a few minutes, the bypass dies again. And when I try to solve it, I see that there is a problem with the IMax. So what are the other options? So we have done already a bypass on MCA. That didn't work. So we went on the bigger vessel. The distal part is working, now the IMax is not working. So we now go into the neck, not in the neck, but in front of the tragus, identify the STA, and try to get as proximal as possible on the STA. But you still see there is a significant discrepancy between the size. But that's the only option that I have at this point. And we go in and do an end-to-side with the stem of the STA. Again, another example of perseverance and not getting disappointed by something that is not working. And finally, we get this bypass work and we have an excellent flow going through it. Postop CT angiogram, an angiogram confirmed that. And most importantly, this patient had a NOVA showing 130 ccs of flow going through this radial artery graft, what she really needed to not be symptomatic anymore. Now let's go to AVMs. AVMs are also among those difficult surgeries that can, at time, become very complicated. This is a patient, 20-year-old, with this complex AVM. As you can see, this AVM is in the motor, basically postcentral area. This patient was seen by some other colleagues who felt that surgery on this is risky because it's very caudal to the motor cortex, which, I respect that opinion, obviously. This patient was very much in favor of treatment. Young patient is scared of this AVM that is causing seizure. We did one session of embolization. You can see how intimate this lesion is with the motor cortex, but based on our functional MRI, this lesion was behind the motor cortex, just behind. So this is a dissection around, and what I would like to focus on here is how to deal with intraoperative bleeding of an AVM. This is an AVM that is minimally embolized, and you can see this kind of bleeding can happen during an AVM surgery. The most important thing is to let the bleed out, the first thing. Never hide the bleed, never pack the bleeding. And the second is get a large-bore suction to clearly see where is the side of the bleed. And then use clips, aneurysm clips or smaller AVM clips, one or the other, to be able to clearly identify and control those bleeders. That's the only way that we can get this, instead of turning this into just chasing the blood back to the brain. So that was just an example, and now we go in. This surgery is progressing well and we're getting to the more difficult part of the AVM, which is deep toward, getting close to the ventricle, and that's where that, again, it becomes more complicated, with more bleeding. Again, using lots of clips, I have found in some of these cases, is the most important aspect that help us deal with this kind of bleeding because coagulation sometimes alone is not enough. And now, then we go back. The AVM is almost 80% out of the brain cavity, but you can see there are these deep bleeders. Again, let the bleed come out, never pack this bleeding. Have the suction in. These bleedings are torrential. Obviously, this is an edited video. The bleeding is more significant that what you see, is longer, and you can see, it can turn into a significant bleed, like almost worse than an aneurysm bleed. But we get it controlled by getting behind the bleeding, direct visualization with suction. And the same thing here, significant bleed from the deep part of the AVM, but we know exactly where is bleeding because we have a large-bore suction and we clear the field. And this is what you get at the end, with complete resection of this AVM. And this patient, fortunately, had a very good, very good outcome. So this is a expected event hemorrhage during an AVM surgery, where you have to be ready for it to control it. Now, there are unexpected ones. This is another AVM patient that we are dealing with with a large, kind of same situation, same location, a little bit more parasagittal. And here, we're going from, this is the left side, this is where the AVM is. We are separating the nidus of the AVM from the . We get the control around the feeders. And the draining vein, there are two draining vein. This is the major draining vein here, so please pay attention to this draining vein. I come to it later. Once we are resecting and separating, leaving the draining vein. I always try to start this section of the AVM around the major draining vein because that's where the most important feeders are, and we work around and separate out. At this point, I am getting around this draining vein, getting this feeders out of the way, and there is a little bleeding happening here after. You can see how this bleeding happens. So it was probably a bad maneuver on my part or maybe a little bit too brisk on this vessel that caused bleeding of this artery. So I try to control it with coagulation. But the problem, the complication here is the unexpected event is that there is no suction. My suction is dysfunctional. So I kinda have a suction that is partially functional. I try to see something. I think that I see the area of the bleed, so I go in with a aneurysm clip to control that area of the bleed because it's becoming larger. But that's the error, here is the error, I don't see well what I'm doing. All I do is that I don't have a good suction. I try to go with a clip to fix that, and I just make the situation worse. And this is relatively at the beginning of the surgery. The whole AVM is still connected and very high flow, and I have no suction. And this is an unbelievable situation that can happen. For a few minutes, I didn't have suction, so I used just that to clean the field. But, again, let the bleed come out. There is nothing that come good with just pushing the bleeding back to the brain. So now I have a suction, but the bleeding has got much worse because I don't have, there's more than one area. So I control one, but you see that the bleeding happened from below that, and I kinda have lost control of this AVM here because of the fact that, unfortunately, I had created several area of the bleed. So at this point, I make the decision to take the major draining vein because this bleeding is going out of control. So we have to do something. This strategy that I was doing is not working. So I have another draining vein that is on the backside, but is smaller, and I definitely did not have the intention to get this major draining vein at the beginning, but there is no choice. In order for me to be able to control the bleeding behind it, the way it's going, I have to take that. So by doing so, this is a decision intraop, and then I'm able to get around in a more circumferential fashion. You see there are several area of the bleeding, the nidus. Most of them are iatrogenic because of my lack of visualization, because that should not happen in AVM surgery. This should not be a usual situation in an AVM surgery at all. And quite frankly, I don't have an experience of bleeding through this. I have done over 150 AVM surgery, close to 200 AVM surgery. It's very rare that we get to this kind of situation, but this is what happens when the bleeding gets out of control. So we have the suctioning and we try to find the area of the bleed. Even if we can decrease the amount of bleeding, is enough for us to get visualization and get to those deeper feeders. And also remember, now I do not have the major draining vein. So this AVM is very tense. So any mobilization around this AVM can cause significant bleeding. But we get that under control, and with further manipulation around that zone, the area of the bleed is under control, and then the situation became calm again. But for some time, this was a very drastic situation for a combination of things, specifically with an unexpected event of not having a suction, a working suction. So now you can see here, this is a more comfortable part of the AVM surgery. That is the deeper part that is embolized with Onyx, and then we get around it and we can work around. The AVM is very tense, but we keep the other draining vein intact, obviously, until the very end, and the rest goes uneventful, with a nice circumferential resection and removal of the nidus. And I check, look inside that there is no residual left. Intraoperative angiography confirms complete resection. This patient had a deficit after embolization with leg weakness, but no deficit happened after the surgery, with MRI and angiogram confirming the complete resection of the AVM. Now going for a couple of aneurysm patients here. This patient's coming in with a blister-type bleed from a carotid blister. We know that these aneurysms are tricky and we know that these aneurysms are not easily clippable. Usually a wrap technique or a circumferential clip technique is used for them. I usually, if I take a blister-like aneurysm for surgery, I would like to trap that segment and do a bypass on the MCA from ECA, an ECA to MCA bypass. Full replacement of the carotid, for a variety of reasons, because we do not want to sacrifice the carotid in the setting of the subarachnoid hemorrhage, plus relatively young patient. But as you can see, this angiogram in the middle does not show the aneurysm. That was day one post-subarachnoid hemorrhage. We repeated angiogram at day five or day six. Patient is severe spasm. Actually, we did the angiogram because the patient was not doing well, because the patient had spasm. And then the angiogram shows that actually, there is a blister aneurysm. So with this spasm, doing a bypass on those MCA vessels is a recipe to fail. So this is the only situation that I would go for direct exploration of the aneurysm, with a try to circumferentially clip the aneurysm. So here, we are on the right side. We have the proximal control, that I put the clip proximal to the aneurysm. And then I start exploring the aneurysm. It seems that a fenestrated clip that circumference the carotid, and stenose a little bit to get that aneurysm would be enough. And we do it under temporary occlusion. This way, we take the pressure off the carotid flow. It looks okay. A little bit of stenose, that's expected and involuntary. But now, on the other side, I created bleeding. Just by touching, the neck of the blister aneurysm tears. So I go back in, put the temporary clip on. And we have two suctionings. Obviously, myself and my assistants coming, helping, and I try to use a surgery saw around that clip to cover the area of the hole. This is a technique that Dr. Spetzler and have popularized. But that didn't work, really. So I had to go with a circumferential clip to get that region under control, and then take the distal clip out. So I caused significant or moderate narrowing of the carotid artery to be able to repair that hole. But this is a situation that, it's a very uncomfortable situation and we really try to avoid getting to this kind of situation that I had. And this is intraop angiography, and this is patient's postop angiography after, just before discharge, when the spasm were resolved. You can see that the carotid flow is good, with the PCom preserved here. And the patient had a good, eventually, a very good outcome. This is a patient with a large aneurysm. Giant, actually. This is, what you see here is a half of the aneurysm because the aneurysm is partially thrombosed, and it's a very isolated left carotid. I didn't think that clipping this aneurysm is an option. And for this particular case, I decided to use the nonocclusive anastomotic technique, which is the ELANA technique, to revascularize the carotid artery and trap that segment of the carotid and devascularize, basically, and decompress the aneurysm. So the ELANA is basically, is a ring that is attached to the graft, and the graft with the ring was sewn to the carotid artery. This is the carotid artery on the left side. So this is the ring for ELANA. We have to make sure the size is okay. And then when we connect the ring to the graft, then the graft will be sewn to the adventitia of the vessel. So you can see that the carotid artery keeps its flow during the whole bypass time. So there is no interruption of flow in this isolated carotid that gives bilateral ACA and a fetal PCA. So that's the reason to do this with ELANA, which is non-anastomosing. So once we do this, and I'm pretty happy and pleased with the way the surgery is progressing, the connecting this graft to the carotid artery. And the next step would be to pass the laser through the graft and through the ring to make a hole inside the carotid artery. But before doing so, we need to have the whole graft connected, which means intracranial carotid artery and also in the neck to the cervical carotid. And this is a slit that I make to pass the laser, once the graft is connected to the neck. Now, I make a pause here. At this point, the graft is in my hand and I am trying, I'm requesting a chest tube to be able to pass the graft from the head to the neck. And this is an error on my side of communication because I did not emphasize or double emphasize or triple emphasize that no one should touch this graft. The graft had a syringe at the tip, and that is, usually we use that when we irrigate the graft. For vascular surgery, called they harvest the graft for us. So the scrub nurse felt that I am handing him the graft, handing him basically the syringe, which is attached with a tie to the graft. Without asking me, and me, without communicating with the scrub nurse, the scrub nurse take that syringe from the graft, thinking that the syringe is a standalone, while the syringe is attached to the graft. So what's gonna happen? Unfortunately, this is the moment that that thing is happening. The graft is being pulled from the carotid artery. So you have a torrential bleeding from the carotid artery, the major carotid artery. The carotid artery that is 75% of this patient's blood supply to the brain. So we go in, we clamp the carotid. At this point, we can't do that ELANA anymore. ELANA takes much longer than usual bypass. I try to control this bleeding, but it's very difficult. It's a massive laceration of the carotid artery. Somehow, we got it under control. We tamponade, two suction on it in a reasonable fashion, not completely controlled. But what we need right now is a working bypass, so I have to do an urgent bypass now. I go to the MCA. You see how the MCA is becoming narrow now and has become sort of stenotic. Is just because there's not enough blood flow in it. So I perform the bypass, I open the graft. And very quickly, this bypass is probably one of the quickest bypass I ever did to reconnect and re-establish the flow into this patient's carotid artery. So we have the radial artery, actually is the saphenous vein to the MCA, a regular end-to-side bypass. And then when this is done, as quick as possible, we go to the neck and make a opening in the neck with a punch. I like to use punch for leaks on carotid artery. And you want to leave the vein under some degree of tension. You don't want to be too redundant because when the vein opens up, it's gonna expand, it's gonna kink on its own. So you want to have actually a shorter graft. So here, we're running suture here, and now we open the graft. We've reestablished the flow. Within 90 minutes, both bypass were done, the flow is going back. And now the problem is that the bleeding happens again from the carotid artery. But now I am more confident that I can go and completely occlude the carotid because I wanted to have some degree of flow still going through the carotid before. And with the ICG, we confirm, with the flow probe, we confirm a good flow, about 150 cc. This is intraop angiography showing revascularization. And this patient ended up only with a supplementary motor area deficit, which improved. So fortunately, this drastic complication ended up with a relatively good outcome. And this is her CTA at the completion of her stay in the hospital, showing a patent graft, robust graft, revascularizing the whole carotid artery. This is another complication in a patient with a giant basilar aneurysm, treated initially with endovascular WEB and coil placement, and a stent going from the basilar artery to the left PCA. And in this patient, follow-up imaging, as you can see, there is a residual aneurysm here. That was at the end of the procedure. Because the plan initially was to do a double Y-stent, but the Y-stent was not feasible. The problem with this patient was that at follow-up, this patient shows up with significant gait problem and cognitive issue and a significant swelling in the basal ganglia and the brainstem. And at this point, we felt that further endovascular treatment for this aneurysm would just worsen the situation. Basically, that aneurysm would become a malignancy of the posterior fossa. And I felt the best way to deal with this aneurysm would be to do a surgical flow diversion by doing a bypass on PCA and Hunterian ligation of the basilar artery. So we are going here with an IMax bypass. Here is the exposure of the IMax in the pterygomaxillary fissure, and connection of the identification of the IMax here. And now we go into the Sylvian fissure. We expose the PCA. I like the half and half exposure to identify the PCA in the carotid oculomotor triangle. And this is the basilar artery with the stent inside. This is the LVIS Junior stent inside the basilar artery. This is the carotid artery here. Here, I'm opening the tentorium. Basically, I'm doing a transcavernous exposure because we want to be as low as possible to be able to put the clip on the carotid artery. This is the third nerve going here, opening of the oculomotor canal, which will give a partial third nerve, but usually always recovered. These are perforators on the PCA. This is the base of the aneurysm, and that's the PCA here. So now that we have this exposure, the goal is to do a radial artery graft from IMax to the PCA. So this is the PCA, the P2 segment, post-PCom. I go and sew the graft to the PCA with a combination of, again, running and interrupted sutures. And then on the IMax, in this particular case, I did an end-to-side. We do usually do end-to-end bypass with the IMax. But here, we do end-to-side because the setup was such that it was easier to do end-to-side. And we have a, we make it a good working bypass here. The problem here is that, obviously, when this bypass is working now, we need to take the demand off because this patient doesn't need this bypass. So if you don't take the demand off this bypass, it will shut off. So the first thing I do, and that was the plan, to go and put a clip. And you can see here, we have the ICG showing a very nice patent bypass. Now that we know that the bypass is patent and there is no problem with it, I go in and put a clip on the basilar artery, on the stent, below the SCA. Technically, this bypass should be enough to revascularize the top of the basilar artery and that flow diversion should work. And this worked for about 30 minutes. We were about to close, that the patients started to have decrease in left-sided motor evoked potential. So I was in disbelief. After half an hour, why this happened so late? So I took the clip off and I thought, I'm pinching maybe a perforator or maybe the stent is closing off on a perforator. And I tried that scenario four times in different location on the stent, but every time now, less than five minutes or less than 10 minutes, the monitoring would drop. So I had to change the strategy. And you can see here is that there's a double origin almost for SCA and PCA. So we decided to just flow divert this in a less ideal fashion, which means putting a clip right on the PCA. So the bypass fills the PCA. The clip is on the PCA. So the carotid bifurcation, I turned it from a bifurcation to only a sidewall aneurysm, which is some sort of a flow diversion. And look what happened. This patient, this is after three months, the whole edema is gone in the brainstem and in the basal ganglia. And this is a follow-up at six months, complete exclusion of the aneurysm, obviously intentional sacrifice of the PCA and no deficit. You can see on the MRI that the patient does not have any stroke in the PCA territory. So this was an intraoperative unexpected event that had to be dealt with, with a new strategy. And finally, this is the last case I will show, is an aneurysm of the posterior fossa. It's a giant PICA thrombotic aneurysm in the patient, who, as you can see here, the patent part of the aneurysm is very small. The aneurysm has, is at the first segment of PICA. And you can see this PICA has a significant loop and contribute to this significant circulation of this, almost both cerebral hemisphere. There is no good PICA on the other side. There is no good occipital artery. So my plan here was to do a vertebral artery to PICA bypass. So the bypass will be performed in this green segment, in the tonsillar medullary segment, and the aneurysm is on the purple segment, on the anterior medullary segment, but it's giant and partially thrombosed. So here we go with the far lateral. We expose the vertebral artery to be prepared for the bypass. And then this is drilling of the . And now we go here and open. You can see this is all the blood in the posterior circulation. This is the aneurysm, completely dysplastic, fusiform. And this is the distal vert. So now, we don't yet have the radial artery prepared, and I get this intraoperative significant rupture. And remember, this is a very significant PICA. This PICA cannot tolerate the occlusion for too long. Most likely would end up with a significant stroke. Now I am in a situation where I don't much have time to do a radial artery harvest and a VA-to-PICA bypass. So we'll look for other solutions. And I realized by mobilizing the PICA, by resecting this part of the aneurysm and separating these two parts from each other, we will be able to use the redundancy of the distal part of the PICA and turn that more complicated bypass, which was a VA-PICA, into a simpler, but unexpected bypass. I was not expecting to do that. And end-to-end direct anastomosis that we did here. And much quicker revascularized the PICA, and the aneurysm now is disconnected. It is now a matter of just going into the aneurysm, opening the aneurysm and decompressing the mass effect on the aneurysm. And you can see this is the PICA revascularized with complete excision of the aneurysm, or partial excision of the aneurysm after. We don't need to completely resect this aneurysm. The mass effect, even if it's partially removed, as long as the aneurysm is disconnected, that's enough. That's basically what we did on that last case. So I think, in conclusion, I think intraoperative complications happen. Most important thing, as, Aaron, you mentioned, is what is your next move? That's, the next move that determines the outcome, not the intraoperative complication, necessarily. We have to find the best strategy to reverse the situation. And most of the time, you have to create the solution to overcome the complication. The solution that you create, most of the time, is not known before. You have to use the creativity sometimes to find that. And that necessitates that moment of sitting back and thinking, and just reflection and deep breath to see what should I do, and certainly, what I should not do? Because that is what makes the situation worse. Obviously, the best way to avoid complications is complication avoidance. It's easy to say, easier said than done. Training, subspecialty expertise and experience obviously play a role. Obviously, the way I'm talking right now, this talk, I would not give this talk five years ago or 10 years ago because we learn a lot of new things with experience. And probably a similar talk in 10 years, I would give it in a different fashion or maybe with way more wisdom that I probably don't have at this point, but I will hopefully have in 10 years. And the most important thing also is to review the complication and find the measures to mitigate. It's very important to self-observe and to criticize. That's the only way that we can improve. You can never stop learning and we have never reached our maximum expertise. The sky is the limit, and that progression continues ever, until the day a neurosurgeon retires. So there is no limits to further progression, perfection and excellence. And finally, pause, reflect on complication, think about improvement and move on. And that's how we will define our career and our future as neurosurgeon. Thank you, Aaron.

- Thank you, . Really enjoyable to watch. Really excellent technical skill. Very difficult complications, not everyday complications. And so reflects really your very challenging practice, or your practice really filled with challenging cases. I really like the way you manage the cases. The techniques and the strategies make sense. I think what you very well mentioned is that you gotta be able to watch your own videos and learn from them. That's been the foundational work of the Atlas, reflection. And be able to really record the video, review it when you're really much more relaxed, after the surgery. Gives you completely different perspective, rather than doing the same during surgery, where you're at the heat of the moment. So I agree with the skills you have shown, the strategies, again, and I sincerely appreciate you being with us and look forward to having with us, having you with us in the near future.

- Thank you very much, Aaron. It's a pleasure, it's an honor to be here, and I would hopefully be here in the future and continue our collaboration and friendship. Thank you very much for having me.

- You're welcome. Same here.

Please login to post a comment.