I've been asked to talk to you about anterior circulation aneurysms. And there's some slides, but there's a bunch of videos at the end, and we can talk through the videos. I think the way Dr. Harbaugh approached the carotid actually is probably a much better way for you to understand. And then we can go back to the videos. Our thing isn't working. Yeah, yeah, downstairs to the lab to teach. Do we know if we can get the remote working? I'll do it by hand for now. Here's my disclosure slide. So always with, if we're talking about, I mean, I know you're here. There's an EMBO part of the course, an open part of the course. You know, how do we decide when we're going to do an open operation? So first of all, is something unsuitable for endovascular coiling? The location of the aneurysm. In my practice, a lot of the basal tip aneurysms are treated endovascularly. And there's a lot of variability. There's variability in the anatomy. There's variability in aneurysm projection. There's what the dome of the aneurysm looks like. Does it look like you're going to have to reconstruct a whole bunch of branching vessels? And I always operate on patients that have a hematoma. I think removing a hematoma allows patients to recover more quickly, particularly a large hematoma. And it also gives you a very quick way of dissecting. So when we talk about the principles of aneurysm surgery, you can apply this to any type of aneurysm. You have to understand the anatomy. All right? So there's an anatomical foundation, and you have to have a complete understanding. So if you're in the middle of operating on, say, an A1 aneurysm, and the patient has a patent communicator, well, maybe if you get into trouble, you can take down the A1 and trap the aneurysm. You would have to know that going in. And so operative planning is a very important step. And your technique. I learned this when I did my fellowship out in Phoenix with Dr. Spetzler. Meticulous dissection. Take your time. Expose everything. When you get the experience of a Dr. Harbaugh doing a particular type of operation, then you can ramp up the speed. But in the beginning, when you're learning how to do stuff, take your time. We always have some type of intraoperative vascular imaging. You'll see in one of my videos, I can do intraoperative angio pretty quickly. But you know, endocyanin green. Some type of way of knowing that the branches and everything are filling and the aneurysm isn't when you're done is incredibly useful. Do we have any technical support to try to get our thing going? So again, back to our anatomical foundation. We have basic brain anatomy and function. Knowledge of the relation of the vascular anatomy and brain structures. So what vessels supply what territory is all quite useful. And as I mentioned in that sort of A1 example, knowledge of collaterals. I mentioned yesterday with our collateral discussion when they were talking about that distal MCA aneurysm and potentially trapping that. You would only know that, and we never, or we very often don't take advantage of the natural collaterals that are available. So knowledge of vascular collateral circulation is very, very important, particularly if you get into trouble. And so really with aneurysm surgery, you know, aneurysms can rupture, vessels can fall apart. Your ability to get out of trouble will obviously impact your outcomes for your patients. Specific vessel tolerance. Which vessels can tolerate temporary clipping and for how long? You don't want to leave a temporary clip on, you know, for 45 minutes because the patient's going to have a stroke. And so you have to know all these things beforehand. So general things about operative planning, positioning. You know, when you bring in the patient, depending on the type of aneurysm, how far lateral you're going to have it for an anterior communicating, maybe that 15 degrees. Whatever it is, review the case beforehand, look at the aneurysm, look at the direction that the aneurysm is pointing, and try to come up with how you're going to position the patient's head. The approach and the craniotomy. This is the area that's changed the most in my practice over the last few years. When I was out in Phoenix, we did a lot of orbitozygomatic approaches. When I came back, I basically did some of that for a period of time, and then I switched more to a general tereonal type of approach for most of my aneurysms. Obviously, for some types of basilars, you're going to go sub-temporal. But one of the things I've been doing a lot now are these sort of mini crannies through eyebrows, and most recently through a blepharoplasty incision, and I'll show you some of that video. This is sort of variable, and you can tailor that to the case and to the patient. Ventriculostomy. In patients that have had a subarachnoid, obviously, well, many of those patients may have a ventric, and you can drain off CSF. What I like to do if I get in and the brain is full is just sort of use the Bajor-Sampson little point and drop a ventric in, drain some CSF, and that gives immediate brain relaxation, and you're not fighting the brain. I don't use any retractors when I do aneurysm surgery, and so having that CSF drained allows a lot of brain relaxation so that I can get the exposure that I want. And then sort of the sequence of operative field exposure. If I'm going for a middle cerebral artery aneurysm and it's unruptured, I may just open the fissure right over where I think the aneurysm is, go down and clip the aneurysm without going down to the carotid. That's not the standard way that you're taught. Everyone says go down, open up the optic carotid cistern. Usually that's to drain CSF, but also to provide you with proximal control. But I think as you get more experienced, you can sort of tailor yourself and go right to the aneurysm if you feel confident enough that you'll have the kind of control that you'll need. And then again, you know, branching vessel and aneurysm neck, you know, presentation. How are you going to have those all laid out before you place the clips on? Here's the thing. What's that? Oh, you see, I didn't know that. See, now the whole presentation changes. I threw this slide in, again, partly because I'm a guy that does both, but partly because I can't tell you how many places I've gone as a visitor or at conferences, and you hear some really, really experienced, well-known neurosurgeons looking at an angiogram, and they can't read an angiogram correctly. I mean, yeah, they can pick out the pathology. They should know how to read an angiogram, and you learn how to read an angiogram by spending time looking at angiograms before you do your procedure, and you'll pick up a lot of stuff. And the way you learn about how to read any type of imaging is you see so much normal anatomy over and over again that when there's abnormal, it stands out. And so think about that for a second, but always start with your standard views. I mentioned this yesterday, AP and lateral views. Someone shows you oblique and things like that, you know, say, can you give me the standard views first? Go back, look at your AP and lateral, then get into your funky views, okay? So there's your AP and lateral. After you've looked at those standard AP views, then you can start looking at your oblique and fancy projections. And then at the end, always that 3D rotational angiogram, those 3D CTA-type images, they're really, really fantastic, but there's one caveat about them. They are limited by whoever created them. So those images can be manipulated and windowed. And so you may lose, infundibulum sometimes becomes small aneurysms, things like that. So an infundibulum, you know, obviously if you window it, you can window out the vessel. You can window out parts of an aneurysm, a small dome. So just be wary when you're looking at 3D angios that somebody has created that that may not be the person that's doing the procedure. And they're trying to make a nice image for you to look at, but you may lose some information in that. So just remember that. I don't have to go back anymore. So just for the anterior cerebral, remember that A1 portion is that pre-communicating or horizontal segment. I'll show you an aneurysm very proximal on the A1 today. Begins at the ICA bifurcation and ends in the ACOM. The A2, as you know, is that post-communicating part. And obviously you need to lay out all of this stuff. If you're just clipping an anterior communicating artery aneurysm, you're really not worrying about A3 through A5 divisions of the vessel. But if you're talking about pericallosal types of aneurysms, then you're more worried about this than you are the more proximal branches. It's just part of that knowledge of the general vascular anatomy. So for clipping of anterior communicating artery aneurysms, you want to see both A1s, both A2 vessels, obviously the communicator. Sometimes if you get into trouble, you can try to close the communicator, but remember there's a lot of perforators coming off of that. So most of the time you're trying to preserve the ACOM itself. You want to see the humerus. These are very, very sensitive. They don't tolerate temporary clipping very much and any kind of spasms. So when you see humerus, sort of lay it out a little bit. And then sort of these orbital frontal frontal polar and perforating vessels, you want to be wary of them when you're doing your clip or clip reconstruction. Just some general pictures of anatomy pointing out the different vessels. Here's our, you know, sort of pre-communicating A1 and our post-communicating A2. The ACOM is there, small aneurysm there. And it's hard to see, but you can see coming right off the A2 there in its classic position is the recurrent artery of Hübner. Here's a blow-up of a 3D rotational angiogram. And again, A1, Hübner coming off, usually most of the time coming off of the proximal A2. It goes in the direction of the A1. In fact, often when you're doing your dissection and you put in, you know, you start to retract and you're looking under the scope, the first branch that you often see is Hübner. And you can follow Hübner right back into the complex. You'll often see it before you find the A1. And there's the opposite side and then orbital frontal branches are usually going in the opposite direction. And of course, your aneurysm. So for the MCA types of aneurysms, and again, we're sort of talking about anterior circulation in general. So you have that M1 horizontal or sphenoidal segment. Just be wary of the perforated branches or meticulous strides that arise in this area. You have your M2 or insular division of the vessel, M3 and M4 of pergola and cortical segments. Just trying to get us up to the point of the videos. Just sort of a slightly oblique. So this isn't your standard view, right? So we start with your standard views, but you start getting into your obliques, you can lay things out the way you need to see them. So general aneurysm technique, I'm sorry that was sort of cut off there on the bottom. You know, the standard teaching is opening the arachnoid over the occupant area of the carotid artery or in an MCA, alternately opening over the distal ciliate tissue. I tend to go right to the aneurysm now for my unruptured aneurysms, but I would suggest that you do that early on. So the MCA, following the internal carotid up to the bifurcation and then walk along to the bifurcation or trifurcation. If you get lost, that's the simplest thing to do. For the ACOM, you can identify one if you can, but Hubner is often that first vessel that's seen. Retraction, you have to be very careful when you're placing retractor because like I said, Hubner is very, very sensitive to manipulation. When you see Hubner, when I'm done with a case, I always put a little bit of fabric on Hubner just to avoid any kind of injury with it. Try to open up your arachnoid plane, it's interhemispheric to give you exposure to the A2 and the ACOM. And obviously when the section is inadequate, take some gyrus practice. I try not to take a lot of gyrus practice. I try not to take a lot of veins. But if a vein is limiting you, obviously you can take it. And if you can't really, for whatever reason, the aneurysm and the complex is embedded in the brain and it's rotated on its side, then obviously you might have to take a little various practice and the patient is fine. So with clipping, you want to mobilize it to tether the dome. Any kind of rectoid adhesions or vessels that are inherent to the dome. We talked about being wary of anything that, plaque or things like that in the vessel wall and hematoma and obviously branch vessels that are inherent to the dome. You don't have to spend a lot of time taking that branch vessel off the entire dome, but certainly in an area where it may be compromised by the clip. In a lot of cases, less is more. I know a lot of people take a lot of time dissecting things off. For me, I like to get in, treat the aneurysm, and get out. So this is our first video. I'll show you this. So I've been doing these eyebrow type incisions here. You see a small aneurysm in a patient with a family history of seborrheic myeloma. It basically was followed, had one dome. We followed it conservatively, and then over a period of two years, we built the second dome. So we decided to do this through an eyebrow incision. My plastic surgeon comes in and sort of masks out where the tuberoral nerve is. It's a very small incision. It's a little local. What I find about these small approaches, first of all, once you get used to them, there's the anatomic keyhole. You're gonna make a little burr hole there. But once you get used to doing them, it really gives you the same exposure that you would through a much larger craniotomy. Remember, when you're doing an operation, you're really working in a very small space. The first one of these that I did, I got into some bleeding. And I started, you know, I was cursing myself with using this approach and all that. But when it turned out, when I actually wound up, you know, putting the scope in the area to fix the aneurysm, it was the same position it would have been in had I had a much bigger exposure. So this is the room that we use here at NYU. And I have an intraoperative angiogram. We bring up the preoperative images beforehand. This is my chief resident sitting down about at the end of the meeting. So first we start here, you see the dissection. With the eyebrow incision, we do go and open up over the optic first just to get some CSF out. Because that's how you're gonna get the relaxation that you need. Because it is a much smaller crane, you need to get a little bit more brain relaxation. As I said, I don't use retractors, but in this situation, you can't get a retractor in there because it's only a one centimeter plus cranial. You can start to see a little bit of the dome here being laid out, and then just opening the arachnoid over the aneurysm. And you can see that one lobe has the other lobe. You can see a cuber vessel being tricked over the top there. Looking underneath the other dome. So this is the chief resident putting a little clip on the neck of the aneurysm. When you're learning, I always sit down next to the chief and I take a look around, and I thought that the aneurysm was still filling, so you see how I moved the clip a little bit for him. Dr. Tanwear Omar, here in our room, he did his, clipped his first aneurysm this week, and of course I had to do a little bit of manipulation, but that's how you learn and get it done. So once we clipped the aneurysm, I made a slight adjustment on where my chief did it. You can see that tiny little opening on the patient's head. We bring in our Z-Go machine. It really, literally takes us four minutes to do an angiogram. You can see the machine positioned over the head. The international fellow is doing the angiogram, and you'll see right away we get all the information that we need. We put in a sheath at the beginning of the case, and you can see we're just checking right away. We get a beautiful digital image. We know that the aneurysm was clipped and we're done. You can see the aneurysm is gone. Everything's going normally, and we've done the pull-out of the Z-Go, and we're done. So in this case, obviously I didn't do it just on any green, just because we have this fantastic piece of aneurysm. And then you just pull it out and close. The closure takes a couple seconds. You close the dura, pop a little piece of bone back in. Sometimes you use a little methyl methacrylate to smooth out the bone, but that's the incision. It's a little nothing. These patients go to a recovery room with a Band-Aid. Almost all of them go home the next day. It's like a 23-hour vision, just like a karate. So let's look at another video. So here's another AECOM. This is, I think, through a regular terianal. The interesting thing about this case is that this vision is a triplication. So we had one dome filming from one side and another dome filming from the other. So there are three vessels here in the middle. There's a periclosal that arises from the communicator, as well as an A1 and A2. And from each direction, there's one aneurysm sitting and another aneurysm sitting underneath it. And so if you didn't understand the anatomy, you would think that we were just filling the contralateral A2, when in fact, there were two different aneurysms pointing in two different directions. So here we're opening up the arachnid again over the optic nerve, and then heading in the direction of the communicative complex. You can see the carotid there. And again, no retractors. This is just being retracted with my sucker and pulling down. You can see a cube here. And then getting back into the region of the complex, here's the optic apparatus. Just draining CSF. And you're beginning to see the first dome that's arising from the ipsilateral side. This is us sort of looking underneath. It seems like it's a little out of focus. Let's see here. Very little temporary. Very little temporary clip. Clipping the aneurysm with a slightly curved clip. And that original position, again, doesn't completely obliterate it. I think we just adjust that a little bit. Again, being cognizant of where the A2 vessels are. In this case, there are three vessels that you have to worry about. So that's that first superior pointing dome. Now this is going after the other dome. So the other dome is pointing at us. You can see the contralateral A2, the neck of the aneurysm. Now this aneurysm is arising between that pericallosal that's arising from the complex, and not the other A2. And so what you're seeing underneath, you're going to see in a second when I look underneath, is that pericallosal. And the clip isn't completely across. And so by looking and examining the position of the clip, you can see there's still some aneurysm there. So you have to advance the clip a little bit against the drain you see is set up in there. And I use this micro-Doppler probe that Johnny Gellishaw turned me onto. It's the device that the anesthesiologist use to put in an a-line. There's a Doppler device that can help them put in a-lines. And so if you take the needle out, you have this really tiny Doppler, which is really fantastic for aneurysm. And so we did our angiogram from both sides that showed the aneurysm was put on. And I'll just show you one, actually I have two other videos and then we'll be done. We're kind of scheduled. So this is a patient that actually had an A1 aneurysm. These are tiny aneurysms, see them here, that are notorious for rupturing at a very, very small size. You see how irregular they look? They're hiding directly on the proximal portion of the A1 and they point directly out of your line of vision. And it's very hard to see them. So here I'm retracting very slightly right on the common and the A1 tape off. There it is. These aneurysms are notorious for rupturing at a very, very small size. And if this wasn't so small, I would have coiled it just because they're a pain to get to. So this is a technique you heard Luke Kim talk about yesterday. Here you put one clip, a fenestrated clip going just on the medial side of the aneurysm. And all that is is a space hole. So that clip is not clipping the aneurysm. It's a space holder so that when you put in the second clip you'll see that it puts the clip right in the area that we want to look. You can see the aneurysm is still right here proximal to it. You can't see it so well but there's some perforators deep to that. So you want to be careful. You see the perforators coming out. You want to be careful not to get those in the clip. And here's the second fenestrated clip that closes down the entire aneurysm. And we'll take off that other clip. But the technique of stacking clips or using a clip as a space holder is very useful. You can see the aneurysm is gone. I just want to show you let's see if we can show you so this is actually for a 3D aneurysm. I'll tell you a little bit about this case and then we'll because it illustrates a lot of points that are useful in clipping aneurysms. So this patient actually had about just under a 2 centimeter I see it by from patient aneurysm that I had coiled. And when I coiled it she actually recurred but recurred in a usual way. The neck of the aneurysm continued to grow and it started to grow towards the A1 vessel. You see this? This was all sort of like new aneurysm formation this area here. And so she was a young woman, originally didn't want to have an open procedure but when the aneurysm recurred I told her that this aneurysm was going to keep growing and she was going to need an operation. So initially I brought her into the operating room to try to directly clip it. You can't really see the dome of the aneurysm there's no retractors here but there's a big mass of oil. So the first thing I've done is I've tried to expose the neck and I'm just trying to put a straight curved clip on, a slightly curved and clip it directly. And so I'm cinching it down and without doubt you can see as I close the clip I'm kinking the vessel there kinking the M1. And that's not good, we know that's not going to be good for her. So let's move along a little bit. So here I'm exposing it a little more and you can see there's a temporary clip that I put down lower on the carotid while I was doing the dissection and you can see there's a lot of coils in this area. So here's your A1 there's a little piece of gel film there on the A2 so I'm repositioning that temporary clip you can take a temporary clip on and off if you want. So if you feel like you've had a temporary clip you can take a temporary clip if you feel like you've had a temporary clip on too long you can take it on you can take it off and sort of re-perfuse for a little bit but here I knew that those coils were going to be a problem.

anterior circulation aneurysms

open surgery

endovascular coiling

anatomy

collateral circulation

operative planning