Greg Zipfel, MD, Washington University vascular neurosurgeon, and Akash Kansagra, MD, Washington University neurointerventional surgeon, discuss aneurysms, both ruptured and unruptured. Discussion includes presentation, diagnosis, and treatment options for ruptured aneurysm along with the more largely present asymptomatic prevalence of unruptured aneurysms in the population. Josh Osbun, MD, Washington University vascular neurosurgeon, discusses cerebral vascular malformations and multimodality treatment options.
Alright well welcome everybody. Um I really appreciate you taking some time to uh you know meet a couple of us from Washington University in Barnes, jewish hospital. Um Look forward to talking with you today about some vascular conditions. Um um We're gonna be talking about aneurysms both ruptured and unruptured and also having some discussions about arteriovenous malformations. Um My name is Greg Biffle. I'm the uh chair of neurosurgery here at Washington University. I'm also a vascular neurosurgeon. Um and worked very closely with Josh Osborne who's listed here as well as Akash Can Sagara. Um Josh Osborne is I'm a neurosurgeon and I do open vascular surgery treat patients with aneurysms, a BMS and crowded disease and also a variety of brain tumors. Dr Osborne is a also a vascular neurosurgeon who treats similar conditions but also does endovascular treatment of vascular disease catheter based treatments. And the doctor can Sagara is an interventional radiologist and the head of our interventional uh neuron eventual team who is an endovascular expert with treatment of vascular disease as well. And dr Osborne and dr Khan Sagara and a couple of other doctors that aren't with us right now. Uh co direct our stroke and cardiovascular center at at at Washington University. So um so that's who we are and wish we were meeting in person and we could find out who you are but I guess virtually we'll stop there with the introductions and move on to our presentations. I think I'm gonna start out, I'm gonna talk a little bit about subarachnoid hemorrhage and then I'll move on. I think we're gonna follow that with doctor Osbon with vast amount for me. Are we doing dr next dr Gonzaga second? Okay, so we'll start with me. I'll talk about stubborn acting, hemorrhage, and some things about managing uh subtracting hemorrhage. And then we'll go to Dr con Saga and then move on to dr Osborne. So I'm gonna share my screen here. Um um This is a little bit of a talk that relates to some of the evidence behind how we treat suburb active and hemorrhage. Um And uh and I'll just start out by saying this is a cT scan and the hyper density Stella hyper density is what we see in the emergency department or with hospital hospital transfers with patients who had a ruptured subarachnoid hemorrhage. That's the that's the blood there. Um These patients also can develop cerebral edema or early what's called early brain early brain injury after subtracting hemorrhage. And that's what this cT shows. There's a lot of loss of salsa and loss of ventricular CSF space. That's adama. And then these patients can also develop uh delayed deficits due to Visa spasm, which is a narrowing of the artery, This is the basilar artery here. And so so these are a couple of common Sekula of subject and hemorrhage that we have to manage and that's why it's really important that not only do we treat the aneurysm either with surgery or with with endovascular treatment, but we also need to get get get them into a neuro intensive care unit with neuro intensive neuro critical care nurses and critical care faculty and and uh and the whole team approach to helping them through what really is a pretty calamitous event when it happens. Um Some of this research funding relates to sub retinal hemorrhage research in the laboratory, but really nothing I talked about will relate to this. We're gonna talk about the first a couple of things, how how often the patients with subtracting hemorrhage. How frequent is that Turns out in the United States there's about 30-35,000 subtracting hemorrhages a year. That only represents 2-5% of strokes. But it turns out that is overrepresented in terms of the amount of morbidity and mortality associated with strokes. Um These patients tend to be a little bit younger than the average stroke patient, but it's a much more severe form of stroke. Um there are certain areas in the country are in the world that are particularly prone to subjectivity, hemorrhages, the Japanese and the finish for some reason. And again, the mean age is about 55 which is probably about 10 years or at least younger than the average. Ischemic stroke patients. So it's a different population and it's a severe form of stroke the most cause the most common cause of subarachnoid hemorrhages, brain aneurysms that's about 85% of the time. Uh then there's this other entity called perry mesozoic Alex subarachnoid hemorrhage. These patients look and act like they have subdirectory hemorrhage. They really do have acute blood, but there's no underlying aneurysm. And and it turns out they do very well with and have a low chance of a complication. Then there's kind of a grab bag of other things that can also cause a subdirectory hemorrhage, but by far the most common cause of a spontaneous subdirectory hemorrhages aneurysm and that the talk is going to be mostly about that in terms of risk factors. Uh, you know, you're not born with aneurysms, you develop them with age. So the older you get, the more common it is For some reason women are more likely to get this than men. And uh and there's certain ethnic populations that are more likely to get some breakfast hemorrhage than others. Um and um and then finally, there is a family history. So it turns out about 10% of patients with cerebral aneurysm or subarachnoid hemorrhage, there's a family history of that and the family history is defined as to first degree relatives with subtraction with aneurysm or subarachnoid hemorrhage. So there was a family history of this and we do do some screening in select populations, then there's a whole host of modifiable risk factors. If you're a smoker, high blood pressure, heavy alcohol, use cocaine and some people think that these modifiable risk factors are our underlying at least two thirds of aneurysms. Subdirectory hemorrhage would suggest that if we can control those, we can lower the number of subtracting hemorrhages happening in the world. Um In terms of how patients present they present with, the most common thing is a thunderclap headache. So this is a headache that occurs abruptly, usually reaches its peak incidents within a few seconds uh defined as at least within a minute. I mean if you have a headache that comes on that rapidly and that severely, that's called a thunderclap headache. And then if you if the cause of that thunderclap headache is hemorrhage, uh things like seizure or altered consciousness or neck stiffness are more commonly associated with it. But none of these features alone, the thunderclap headache plus these other things can reliably distinguish between a hemorrhagic cause of a subject of a thunderclap headache versus a a non hemorrhagic cause. So you have to do some additional work up including a cT scan, which is by far the most common imaging study that we do in the emergency department. Uh If you do the cT scan uh pretty acutely within 12 hours with modern uh cT scanners, it's actually very very sensitive for subarachnoid blood. But if it's delayed in any way. Uh and then then you can, the cT scan can miss uh subarachnoid hemorrhage and that's when we turn to lumbar punctures. Um uh lumbar puncture is can identify Xanthia chromium, which is this yellow discoloration in the spinal fluid which comes from breakdown of red blood cells um That takes a few hours. But but once it happens that is something that we look for. Um That suggests that this is a real subject of hemorrhage and there may be an underlying vascular cause. And when you have either a ct positive or lP positive subject and hemorrhage then we need to do additional vascular imaging to determine if there is an underlying aneurysm. We use M. R. I. Occasionally I use it mostly when patients come in delayed fashion because an M. R. I. With flair and T. Two star and and and and and blood oriented sequences. Can really see sub acute blood really well. Like you see this example up here while cT scan can really be poor at that. So for people presenting in delayed fashion MRI I think can be helpful but otherwise we don't use it very much for subdirectory hemorrhage. But once you identify it then you need to do some vaster imaging which could be a catheter angiogram. Like you see here really nice look at an anterior communicating artery aneurysm. You can do three D. Renderings of these and geos which gives you all the details and you can see this branch and you can see the neck and all the anatomy. You would need to determine how you might want to treat that aneurysm. There is a small risk associated with this. That risk is very small at wash U. We do I think 1000 diagnostic Anjos a year or something along those lines. There's a very small chance of stroke or other complications. Some people think it might be a little higher during subject on hemorrhage. But I think that has more to do with aneurysms are unstable and they can re rupture and sometimes that occurs in the angio suite but not necessarily related to the angio itself. So we do a diagnostic Anjos a lot. But our first line of of imaging usually is a ct angiogram. This is a really nice one here. Up to the right with a large middle cerebral artery aneurysm usually depicted there. We do. Usually patients get a ct scan with subtracting hemorrhage and then the C. T. Angiograms done while the patient's on the table. And that's helpful because you can identify an aneurysm early. Um If something has to happen emergency or urgently you can use that for for your imaging or for your surgical planning for example. Um And then we often will follow it up with a catheter angiogram which gives us a little bit more information than the C. T. A. Um I'm gonna skip this. Um part just for brevity here in terms of management of subtracting hemorrhage patients. Once you identify the subject of hemorrhage uh their patients are gonna be admitted to the intensive care unit. We now have 44 bed neuro icu it's on two different floors. 24 of those beds are brand new as of August of 2019. Um And we have an outstanding group of neuro critical care doctors and nurses to take care of these patients. Which is really important because these patients can change from hour to hour and you need to be able to identify that and intervene. So they sent him to the neuro ICU. Q one hour neurological examinations. Many of these patients will develop hydrocephalus. Um The CSF pathways need to go through the arachnoid, granule ations near the sinuses. But that's where the subarachnoid blood can be and it can disrupt that re absorption of CSF. So a lot of these patients get hydrocephalus. Some of them sometimes that is shown by uh enlarged ventricles. Sometimes it's not. And so if someone comes in with altered consciousness, if they're if they're sleepy or if they're in a coma or they're they're in a stupor. We always would have intrigued colostomy in them because many of them will get better. Uh And actually uh you know cognitively cognitively or mental satisfies will improve as you treat the hydrocephalus. And so it's really rare that we don't do that because we identify patients who otherwise you think would do very poorly who actually could do quite well. So that's really important in our in our in our management blood pressure management, important if it's an insecurity aneurysm. We really are really strict with keeping the blood pressure well controlled. And then once the aneurysm is clipped or coiled, then we actually permit hypertension. And there's some data that suggests that that may decrease the chance of some of these delayed things from happening like visa spasm or delayed cerebral ischemia. We're pretty aggressive with controlling glucose and hypothermia because there is some evidence that that that may improve outcome. Not for sure, but probably um A lot of these patients are actually hyper kogel um and so they're actually quite prone to DVT and PE s and so we put them on prophylaxis for that and then they're prone to seizures and we put them on prophylaxis for that. So that's kind of the general management of of our patients. There actually is a lot of data that transferring to a high volume center matters for supper, activate hammers. These are just a smattering of some of those publications um And this probably has to do with just seeing enough of something having the right uh specialties like microsurgery and the vascular neuro critical care, the right nursing. Um And and that's probably why things tend to go a bit better when you get to services that I see a lot of this. We we admit I think somewhere around 230-140 subdirectory hemorrhage is a year. Um I'll skip this one. Um there are some trials that guide us in terms of how to manage subject on hemorrhage patients uh the re bleed rate is high. So if you have an initial subtracting hemorrhage, the mortality associated with that is about 35%. But if you bleed again, the mortality is about 75-85%. So we really want to avoid the re bleeds. Um And that means that we need to intervene and intervene with with coiling or clipping. But there actually is some nice data now that for a short term putting them on the anti fiber fiber olympic drugs like T. X. A. Or epsilon amino caprock acid can actually reduce re bleed rates. And so we we do currently put them on that in the short term to get them to bridge them to aneurysm treatment and then we get them off that medication. So there are some data on that um skip through that and then we get to how to treat these aneurysms and treatment is either clipping as you see depicted on the left, that's a middle cerebral artery. Aneurysm being clipped. It's a little bit an older picture because these uh these uh these are retractors that you see there, we don't use those anymore. There's been kind of a revolution of retract earless microsurgery that tends to have better outcomes. So I I rarely use uh retractors now. But this is an example of the aneurysm and then it being clipped or it can be coiled uh and the catheter often goes in through the femoral artery. Although uh many interventionists are now using the radial artery and the risks as an access point. But ultimately the catheter goes through the arterial system and and and the micro catheter goes in the aneurysm to call the aneurysm off. And that's another effective way of treating a ruptured aneurysm. Now, there are trials that guide this. Um and the best one, best known one is called sad. Uh And this was done primarily in europe with a little bit of representation in north America. But basically what happened was if they had a ruptured aneurysm and and uh the aneurysm was reviewed by the surgeon and the endovascular therapist determined that the patient was a good candidate for both corn or clipping. Both seemed reasonable. And that clinical equipoise uh was established. And then they were enrolled in the trial and they were either clipped or coiled randomly and then they were followed for outcome. And the key here is uh a year out, the primary outcome measure, which was functional, which was a functional status by modified ranking. The patients who were coiled did better than those that were clipped by 7% absolute risk reduction. So, this was a game changer. Uh for for everybody in the field and really has led to us. Uh calling a lot more ruptured aneurysms than we did in the past. Now, the re re bleed rate is a little higher in the coiling group than surgery. Um, and there is some data that suggests that because of that Increased re bleed rate for the coiled aneurysms. And because in young patients, uh that difference in outcome actually was very marginal. Uh in patients who are under 40, it seemed to suggest that the the the the benefits of of of of coiling over clipping that were at large there in the trial. We're we're not as present there in the the young patient population. And then the durability issue came up with re bleeds. That suggested to the investigators. These are the investigators that ran this trial that patients who are particularly young may be better served with surgery than coiling. Now it turns out, I don't know the percentage, but probably 5% of subtracting hemorrhage occur in this age, 95% occur and and people who were in their forties or a holder. But in that younger population, we do often pick surgery over coiling, all things being equal. There's another trial that had basically similar results. I don't I don't want to go through that. But the synthesis is this, if you're a young patient under 40 and the aneurysm in the anterior circulation, I think there is data that suggests that clipping maybe better. But the majority of patients are older than 40. And then the data, I sat in this other trial called brat suggests that coiling is better and if the andrews is in the post your circulation, the vertebral artery, the basilar artery, then the data really clearly is uh favors coiling. And we really coil most of those patients. Um So that's kind of how we manage things uh in terms of the initial stage and um I might stop there. There's I have more to talk about if if we wanted to get into that. But I I want to make sure that my colleagues have uh enough time to talk about unruptured aneurysms dr Osmond can talk about vascular malformations. And I think we want to definitely leave some time for questions as well. So maybe I'll stop there. All right. And I will pick up where doctors have felt left off and I will be talking about unruptured aneurysms. So um hopefully you guys can all see that. Um So actually, sorry, let me make sure I'm sure in the right screen. Okay. There we go. Um So, to build off of what doctors that all talked about, You know, we have the uh A large population of patients have unruptured brain aneurysms. And this is a very common clinical scenario. We do a lot more brain imaging now than we did 2030 years ago. And so this is a very common mode of detection of patients is they're not just presenting with ruptures. Um Here are my disclosures. Uh I will be discussing some off label uses of devices and several of them have investigational or exempt status from the FDA. So quickly we'll talk about for the background um evaluation and treatment of these aneurysms and the evidence that sort of guides the decision making. Um I know we have a mixed audience so you know sort of target the middle of the group. I know several of you are have quite a bit of experience with the aneurysm. So um hopefully there's something here for everyone so aneurysms can present in a multitude of ways. The most severe is rupture as doctors in field just talked about. That's a really catastrophic event when that happens. But there's a whole spectrum of other modes of presentation, the most common of which actually is a symptomatic presentation. We ganda picture for headaches and oh we found this aneurysm and it's not because it was doing anything it's just because we happen to look and uh and the way we manage that patient and the options we have of managing that patients are different quite a bit from the rupture situation. Um One of the true very important facts that we have to keep in mind when discussing these aneurysms is that most brain aneurysms do not rupture um depending on which series you look at, there is thought to be anywhere from about 3-6% overall prevalence of aneurysms in the natural population. Um so a lot of people walk around have brain aneurysms. However there is a much lower risk of cyber active hemorrhage Based on you know a fairly typical 80 year life expectancy. So even if you have any aneurysm most of the time you'll never know it unless you do a scan and it will never cause you problems. Um Quickly I'll just give a quick word about methods of evaluation. So um doctors doctors inflammation C. T. A. Is a very common method of evaluating for aneurysms that's involved. I. V. Contrast is really quick and you can do it just about anywhere. Um You know it is susceptible to artifact and uses radiation. Um M. R. A. M. R. Angiography is a similar way to show aneurysms using M. R. I. Instead of C. T. Um Contrary to popular belief it actually does not require I. V. Contrast. So this could be a really good option for for patients who for whatever reason um have access or can't receive contrast for any other reason. Um And it's also a really good way to follow aneurysms. But again like C. T. Is susceptible to some artifacts. Uh Really the gold standard for looking at aneurysms is a digital subtraction angiography. Sometimes also called catheter or conventional angiography. That's where um an interventional issues the catheter and injects dye directly into the vessel of interest. It is unquestionably the best way of looking at aneurysms in terms of level of detail but obviously it's not offer everywhere and it's a little bit more invasive and laborious. Um And as you know in terms of treatment options um you know one of the main states that the sort of original mode of treating aneurysms is open and surgical. That's where a neurosurgeon um you know exposes the skull and actually temporarily removes a portion of that skull in order to gain access to the aneurysm. Uh and sort of clips it with this closed pen like device that pinches the aneurysm from the outside. There's a cartoon picture and a real life picture of what that looks like. Um Nowadays we also have a variety of endovascular approaches. These have really these really sort of came online in the mid nineties and uh since about 2005 they have really picked up steam. Uh The latest Medicare data suggests that about 80% of the aneurysm to the U. S. Are treated by endovascular means nowadays. So it really has been sort of a um a tidal wave of change. It's just a really short amount of time. So with an endovascular approaches, an interventional ist access the artery of the needle and then through that needle inserts of wire. And then that wire basically serves as a as a set of railroad tracks through which over which they can navigate a variety of devices historically have done this from the femoral artery. Nowadays. Again, his doctor's information, we're doing a lot of these interventions from the radio artery. Um What does this look like. So there's uh you know, endovascular, there's quite a few treatment options. It's more than just coiling and some of these options are you know, perfectly good for unruptured aneurysms but are not good options for rupture. So here's where you start to see some differences between those two populations. So um in the coil organization we just packed the aneurysm chock full of these coils and try to impede blood from getting into the aneurysm. Um what does that look like? I'll try to show a video hopefully that will carry over well over the internet. But um you know, We we guide a very small wire. These are tiny wires. These are 0.014" across. And we carefully place that wire inside the aneurysm and then threw over that wire. We passed this micro catheter and use that position that inside the aneurysm. And then after removing the wire we deploy these very, very soft, very flexible coils that we used to to fill up the aneurism. Um This can it's very very it looks very easy and the animation like this, but this can be tricky depending on um anatomical factors. But with modern coils and modern micro catheters were able to treat a pretty large number of aneurysms This way these are detachable coils, maybe we can deploy them in a controlled way. And only once we like the way they form do we actually detach them um in this manner. We kind of just pack it in with a series of coils and um video is almost over here. But the end result is that, you know, we get a very, very dense coil pack and that's that's effective in stopping blood flow entry into the aneurysm. Um There are related methods of treating aneurism. Sometimes the neck of the aneurysm, the opening of the aneurysm is too wide to hold, hold the first coil and in order to provide some stability, you have to introduce a temporary balloon that's just there during the coiling process and it serves as a temporary scaffolding so that you can build up this solid mass of coils. And once that massive coils is built up you can deflate the balloon and remove it. So that's called balloon assisted coiling. Um For an even wider necked aneurysms, sometimes a temporary scaffold isn't enough and you need a permanent scaffold. And the stent assisted coiling is just that you place a stent and now you've essentially bridged the neck of this aneurysm and then you can you can fill in the, the aneurysm with coils and the coils will be held in place by that stent. Um more recently, since, since late 2000s, we've had a real revolution in endovascular treatments with these so called float inverters. Um these are like stents except they have much more metal to them. And what that does is that actually in addition to just providing or instead of just providing support for coils, there's enough metal in it that it actually redirects blood flow out of the aneurysm. So I explained this to patients as the difference between taking a chain link fence and rolling it into a tube as opposed to taking a mesh screen door and rolling it into it too. Um and uh and this is another way of treating the aneurysm. It's one of the appeals of this method is that you actually don't have to access the aneurysm or put devices into what is ostensibly the weakest part of the the structure. And then more recently we have other devices. This one is called the web. This is essentially, it tended to be a replacement for coils. In some cases where you don't have to build up this coil mass, piece by piece. You can actually just deploy one device that fills up the aneurysm and you know, in one fell swoop. Um you know historically the way we've thought about Pope universes. Endovascular treatments in the unruptured setting is that um open treatments, generally speaking, have a uh slightly higher perry operative complication rate and a longer recovery time, but a lower recurrence rate. So the durability tends to be better of open surgical treatment. So the 10% complication rate versus the 1 to 2% Recurrence rate compared to, say, coiling based methods which have a lower complication rate of about 5%. Um the national series and a recurrence rate of about 10%. Um the data on floating version is more recent, but it suggests that the complication rate is quite low and that the recurrence rate may be lower. So this dichotomy is changing a little bit with newer technology. Um I will also mention that some of these endovascular methods really do benefit from anti platelet therapy with aspirin and Plavix for instance. Um These are not drugs that should be used lightly in the in the rupture settings. So in the setting of unruptured aneurysms we have access to treatments that rely on these medications. I'll talk quickly about the risk of rupture. Um so there are a few studies mostly from the 90s um that look at the risk of rupture and they're nicely summarized by uh this study called phases. And that's actually an acronym for uh the principal the conclusions in the title. The risk factors that are associated with risk of aneurysm rupture. So its population and I'll go to what is being hypertension age size earlier subtracted hemorrhage in sight. So what phases was is a systematic review and a patient level pooled analysis of over 8000 patients from six different cohort studies including a couple of very famous studies. The international study of unruptured intracranial aneurysms and the unruptured cerebral aneurysm studies. Um this I consider sort of the best and largest dataset for the natural history. Risk of an aneurysm but I will mention that it's flawed by the fact that several of these constituents studies including I. S. U. S. A. And you cast our observational you know, they just took a cohort of patients and some of them were treated kind of at the physician's discretion and some of them weren't the ones that weren't were trapped over time. Obviously there's a little bit of selection bias in that. So what does faces tell us? So on the right is actually the table from their from their main paper, but it tells us that one of the risk factors for rupture is population. That for whatever reason, patients of Finnish descent or japanese descent have a higher risk of rupture than patients from north America or the non finished parts of europe. Um the differs by country but it seems to be 2-3 times higher risk. Um If you have hypertension, there's a higher risk. Again, the definitions of hypertension vary by study, but clearly hypertension is associated with rupture risk. Um Asia is also associated with rupture wrists and you know, it's not a strong effect. As uh say some of the other factions talk about here, Probably the most important one is aneurysm sides. So um you know, looking at some of the data here at the bottom and if you're in the small category 5-7 mm, it's uh You know, slightly increased risk of rupture compared to aneurysms less than five. But you know, as you start to increase in size 7 mm, 10, 20. The risk of rupture really really goes up pretty quickly. Um earlier subarachnoid hemorrhage from a different aneurysm also seems to be predictive of risk of rupture of other aneurysms. And then finally the site of the aneurysm plays an important role that there are. Certain sites. For instance aneurysms rising near the origin of the post here, communicating artery seems to be at particularly high risk of rupture. Um and so, you know, the actual site of the aneurysm really factors into the natural history, history, risk and phases is really nice. So they basically take these studies and they characterize those individual risk factors and then put it together into a risk and overall risk score that, again, taking account population hypertension, age size of the owners of earlier subtracting hemorrhage and sites and this provides a reasonably um robust way of kind of at least ballpark in the risk of an aneurysm rupturing. So what you see here is, you know, depending on the number of points to get each of these categories, uh you know, you get an overall sum score and that's overall score. You can kind of plug into this and you get a uh predicted probability of aneurysm rupture and depending on the score, these are some of the five year risks of aneurysm rupture. So um you know, I generally think of uh phases risk, scores of, you know about seven or above or kind of the point where it's starting to get my attention now, that's the risk of rupture. But you know, we have to how do we actually factor that into who we treat? So the way I think of it is that does the one time risk of treatment away, the accumulating risk of non treatment. And then there's a little bit of a balance there, right? So there's the rupture risk which we get from the phases data. Uh that data has to be taken to count, you know, what is a reasonable time horizon? A patient who is 95 years old and not dialysis has a different life expectancy than someone who's 20 years old. Um And then we don't talk about it a whole lot. But there are some patients that just have debilitating anxiety that they saw a loved one diver ruptured aneurysm. Um You know, it's it's kind of cruel to say, well you don't meet the numbers, goodbye. You know, it's I think there has to be some consideration given to them. So those are the those are the things that would sort of make you think about treatment, the things that would make you think about non treatment or that there's peri operative risk, right, no matter what treatment options you use, there's there's some risk and there's also a risk of retreat. Um And again, these are these are informed by the phases data and as well as the device trial data, both for clipping in for, for coiling. So I'll just show a couple of cases here. Um This is a 31 year old male who actually was getting a spine injury for for some workman's comp thing. Um And that spine emery detected this incidental um superior cerebral artery aneurysm there. You can see it on the right shown by brain M. R. A. With the arrow on it. Um So so no history, no family history of aneurysms, no prior history of any symptom Atala ji related to this. Um So the question is, should we treat this patient? Um No he's young, he's 31 years old, has a five millimeter poster circulation aneurysm. Um You know there's a lot of kids running around. So he was interested in treatment and he has a reasonably high risk score. So here are the pictures from the angiogram. You can see that superior cerebral aneurysm show up pretty nicely. And here are the initial images showing that aneurysm. This is a patient who had treated with balloon assisted coiling. And you can see the after images on the far right show that there's no more contrast getting into the aneurysm. So he's a patient who went home the day after this treatment and actually went back to he was in kind of contractor. He didn't want to take much time off work. So he went back to work 2.5 days later basically. So really great dot com. Um here's a patient known to both myself and doctors fl so this is a patient 55 year old healthy woman um underwent brain imaging for dizziness. The M. R. I did not reveal any cost for dizziness but it did reveal to aneurysms and ophthalmic aneurysm and a middle cerebral artery aneurysm. Um Here on the left two panels you can see the authentic aneurysm. It's about a five millimeter ophthalmic aneurysm. And then on the right you can see there's actually a fugitive form six millimeter distal left middle cerebral artery. Uh So both of us talk to the patient about the different treatment options. We said you know, clipping or endovascular treatment of both options for the economic artery. And you know, endovascular treatments are probably available but the best option for this distal perfusion for mannerism. Um so the question is should we treat this patient again relatively young, very healthy patient. Aneurysms that are at least one of these is about six in size. So uh and she was quite nervous about having the aneurysm. So we did treat this. We did offer treatment in patients and she actually underwent multi modality treatment. So the left ophthalmic aneurysm you know was clipped. Um And here's the picture of that clip shown with Big Arrow. And then on the image of right there's not much to look at the aneurysm is gone. The clip is nicely including that dan Anderson. So she went home, this is uh dr situated. This clipping. She went home post update three really quick recovery. and and she did very well from the about six months later we brought her back for this other aneurysm. Um This was a future for mannerism. It's it's an off label use of a flow diverter but this is a patient were able to float over it with a pipeline embolization device. The middle image here shows where the aneurysm is right after the pipeline was implanted. And six months later we brought her back for repeat angiography and the vessel looks like it should be. There's no no residual aneurysm there. She went home on post op day one after the flood of burger treatment. And she's also done really well and uh has no has no ill effects from either treatment. And then finally I'll show sort of the opposite situation. So this is a 70 year old female who underwent brain imaging is part of an acute stroke evaluation. You know many of you may be familiar with the fact that we do a lot of, from back to me now is sort of the the newest and the really most effective treatment we have for severe ischemic strokes. And C. T. A. is typically part of that work up. And the C. T. A. Here aside from showing no large vessel occlusion to treat with lumpectomy did show an incidental aneurysm completely unrelated to the stroke. Um You know so we uh we talked to her about treatments um you know she's seven years old. she's had this acute stroke demonstrated incidental 4.5 millimeter left abdominal aneurysm. Um And looking at a recovery, you know, she she mostly recovered from the stroke but you know she's uh but she's definitely require some assistance around the home. Um You know, not not unfortunately not someone who you know may have 30 years of of life ahead of them at this stage. Um So we talked to the patient went over these data and we ultimately elected uh and and you know, along with the patient to follow this patient, she she could not have an M. R. I. For for her own preference, she's very claustrophobic. So This is the initial head CT and we followed it over time. We initially didn't follow up CT one year later. And uh you know, the resolution is not as good as the angiography but it's this is a noninvasive test and a very effective way to follow mannerisms. And we followed her at sort of increasing intervals over several years and are kind of now entering the territory where we she's almost 80 years now and we're probably gonna stop following pretty soon. Um So my takeaways at least in the unruptured aneurysm world are that most brain aneurysms do not rupture. So for those of you who see patients with aneurysms like me sometimes they are just beside themselves with fear that they have a ticking time bomb. Um patients really love the reassurance that if it's an unruptured aneurysms uh it's not an emergency. It's uh you know it's maybe something to deal with but it's it's not about to explode. Um C. T. A. M. R. A. And uh angiography all have a role in evaluation and that endovascular and open treatment options are both important and being able to direct patients to the rights mode of treatment is really one of the ways in which we can ensure that we're employing the lowest risk option um in my practice phases uh informs the evidence based assessment of the natural history risk of any aneurysm. And and my recommendations to patients are based on a balance of this natural history risk versus the treatment related risk that I just went over. So thanks very much for the time. I know dr Osborne has a lot a lot more to talk about with the A. B. S. But if you guys have any questions outside of this meeting. Happy to field questions by email. So again I'm josh Osborne and the department of neurosurgery and also worked closely with the interventional team. Um And I'm just gonna talk about cerebral vascular malformations and some of the multi modality treatments that we offer. Um So a couple of disclosures. I'm a consultant for these companies but won't be mentioning any of their products. Um And then I just wanted to acknowledge both my coin and Greg's it full because a couple of my slides come from some historical department lectures. Um So vascular malformations come in several different types. Um uh We we can really think about them in terms of capillary malformations, various venous malformations, ah cavernous malformations and then things that are arteriovenous shunting lesions which include arteriovenous malformations, dural arteriovenous fistula and cavernous crowd officials. And he's really differ by how pressurized they are within the arterial system. And these first three types of malformations are really low pressure lesions that are that are really more venus lesions than they are tyra lesions. And so they don't typically result in any sort of high pressure brain hemorrhage, arteriovenous shunting lesions on the other hand are high flow high pressure lesions. And these can certainly cause more devastating consequences for the patients because they are under high arterial flow. And I'll explain some of the differences between these throughout the talk. So capillary telling cicadas are sort of a nest of dilated capillaries uh that that lack smooth muscle wall and elastic fibers. Um We can commonly see these incidentally on brain MRI's. Uh This is a patient with H. H. T. Who um has a couple of these small capillary challenging stages. They're being pointed out on this representative brain MRI scan. These are actually fairly common. Probably show up in about 0.3% of M. R. I. S. Um They're usually completely incidental can be seen in any age. They have virtually no hemorrhage risk. And we essentially never treat these because they're just sort of incidental findings on scans that don't really cause any known consequences to patients. Um developmental venous anomalies can be seen a little bit more commonly on M. R. I. S. These are sort of radio arranged dilated anomalous veins that can really converge into a fairly large transportable draining vein of the brain and they can be quite large lesions on an M. R. I. Such as on this representative scan here and we'll again show up in somewhere between half and 1% of brain MRI's. Um They can really be diagnosed at any age. Don't really have any known associated diseases and also have an extremely low to negligible hemorrhagic risk. Again we don't offer any specific treatment for these because they're so common and and don't really have any known adverse to Coachella, cavernous malformations um are yet another type of lesion. These are sort of endothelial line, tightly packed signing soil channels without intervening brain Brinkema. Um They can be again prevalent and somewhere between 0.5% and 1% of brain mris. Uh They can cause some neurological consequences such as seizure small bleeds or be incidental. We typically see these more in the 20 to 40 year age range. Um And they can certainly be a hereditary and there are several known genetic mutations that can cause these two clustering families and cause multiple lesions and in a single patient Um they do have some bleeding risk approximately 0.5% per year on the whole. Um And uh sometimes when these are causing symptoms such as seizures are repeated hemorrhage. We will treat these with surgery, but most of them have a very benign course and we simply just observe them. Um This is sort of on the left a pathological slide showing these dilated sinus little channels without much structure to them. And this is an inter operative photo of a caress malformation on the surface of the brain. That kind of has a classic mulberry appearance to it. Um So, you know, again, um almost, you know, somewhere between half and 1% of the population accounts for a fair number of all intracranial vascular malformations. And then uh I want to make again the point that they can be sporadic or genetically inherited. Uh So we we consider them sporadic uh or non genetic if the patient has less than three of these lesions in their brain And we think this is the case more than 80% of the time. Uh And most rations just have one solitary single caverns malformation when patients have three or more lesions. Uh we think that this is a genetic syndrome causing the carriage malformation. There's three genetic close i uh that have been identified that can cause um uh these legions to form in patients. And we call these genes CCM 12 and three. And uh we know at least that CCM one variant is caused by a mutation in the crypt one gene which is a tumor suppressor that regulates angiogenesis. Um So certainly uh you know we we get a history from a patient that they have seizures and have had multiple family members with seizures that have been undiagnosed that this may be something that's being passed down causing familial seizures. Um location can be really anywhere in the brain or brain stem. Most of them are super territorial um in the cerebral hemispheres but they can certainly be and uh the brain stem the thalamus and basal ganglia and the cerebellum in some cases. And then just a couple of ways that they present this left most panel is someone with a sarah Beller Karen's malformation that's hemorrhaged into itself multiple times and actually has a fluid pocket because of multiple hemorrhages patient in the middle is just an incidental one in the right frontal lesion. And then the panel on the far right is someone with a pond tinkerers malformation that's uh sort of protruding into the fourth ventricle a little bit. So they can really be in any location. Again, we tend to observe the ones that were found incidentally are asymptomatic or are in an eloquent location. Uh And then we'll operate on ones that have been shown to have multiple hemorrhages over time or causing seizures and are in a location that's safe to be removed. So I'll move on now to Evie shunting lesions which again are mainly the arterial venous confirmations. And the during the official is I think it's important to think a little bit about normal blood flow and circulation before we talk about these lesions. So normally blood flow is gonna come as arterial blood flow from the heart under high pressure. It's gonna then fan out into smaller arteries, arterials and then eventually become a capillary bed. Where as we all know, the tissue will extract auction nutrients and then um take the deoxygenated blood in the ventricles and veins back to the hardware cycles all over again. The key feature of these arteriovenous malformations and their officials is that there is no intervening capillary bed and that there's some sort of direct connection between arteries and veins where the vascular resistance of the capillary bed is is not there. And the venus system becomes highly pressurized with arterial blood flow. Arteries are nice thick vessels with a muscle layer to the walls are built to handle high pressure, veins are not they're very thin walled vessels that are meant to handle low pressure. So when they're seeing arterial blood flow they either dilate to a large degree or will rupture from a weakening in the wall over time. And that's why these arteriovenous malformations and their official as um can be very problematic for the patient. So I'll start with brain A. BMS. These are dilated feeding arteries, arterial is draining veins with usually an intervening a VM. 90s. As you can see in this cartoon picture, a thin walled, this plastic vessels within sort of a dis plastic, idiotic brain tissue. Um And the draining veins can tend to become highly pressurized and dilated and high flow. And because of that these do have some risk of rupture over time or causing adverse effects of the surrounding tissue, such as seizures. Um Low grade A. B. M. S are a little bit smaller lesions. Uh They usually have more superficial venous drainage and they're usually in non eloquent cortex whereas the higher grade lesions are much larger and can encompass a large swath of tissue um Such as in this case we're really the entire cerebellum is being encompassed by this large A. VM. Um we think that the incidence of these is around 0.5% of the population. They're rarely familial, they can be seen in the setting of hemorrhagic hereditary, telling Jack asia. Ah And and be genetic but we we in general do not think these easier genetic lesions that are passed amongst family members. And then um we worry about them because um about 40, of all patients who have known a BMW known because they presented with a brain hemorrhage. Um And then others can present with seizure. We think this um represents somewhere between 15 and 40% of all patient presentations and over the course of an A. B. M's lifetime. We think up to 70% of patients have seizures. Um Some patients have headache, um Others have progressive neurological deficit and then increasingly commonly as we saw as a theme. And uh dr Gonzaga's talk with more and more advanced brain memory techniques. We're finding these more and more incidentally on on brain. MRI's done for a different reason. Um they have a high annual hemorrhage rate of somewhere between two and 4% per year and a re hemorrhage rate um in the first year after the hemorrhage can be 6% or even up to 10%. In some studies, Each bleed can be very devastating. Um uh you know with permanent neurological deficits and up to 25% of patients And death and 10 to 15% of patients. So in general when we find one of these we we try to treat them. There's three basic modalities of treatment. The first is is surgery. The pros of surgery is that it eliminates the hemorrhage risk acutely by cutting the A. B. M. Out um has questionable seizure control rates but on the whole more patients recover from their seizures after the ADM is removed and not. And then depending on you know where the location is, it can have you know certain you know neurocognitive deficits and then we also have to think about the overall long term risk of the A. VM being present and the risk of surgery and and sort of what the patient thinks about undergoing such a major operation because it is an invasive procedure. There are always going to be a surgical risk and complications from surgery that we have to take into account is going to be a hospital ation for a few days if it's an elective procedure. And and sometimes even on the order of weeks it's a it's a ruptured A. Bm. And in general these patients have a fairly long recovery course when they have an A. B. M. And need surgery for it. Gamma knife or stereotyped radiosurgery um is less invasive. It's an outpatient procedure. There's virtually no recovery period but it does provide a gradual reduction in the A. B. M. Flows that's working. And you don't immediately reduce the patients hemorrhage risk as it takes about 2 to 3 years to have the maximal effect of gamma knife. It does have a higher chance of an incomplete treatment and depending on the size and location of the A. b. m. the cure rate is somewhere between 50 and 80%. And we usually use this for a larger lesions and eloquent brain where the surgical risks are too high globalization um is a way to access the A. B. M. From the inside of the vessel. Similar to what we're doing with aneurysm treatments. And we can inject various glues into the aneurysm that block at least a portion of the A. B. M. Off. Um This is a less invasive treatment. It's got a fairly short recovery period. It's an excellent adjunct to either surgery or radiosurgery. Um More and more so with advanced endovascular techniques we are seeing that some A Bms can actually be cured by this but it's a very small number of A. B. M. S. And we certainly can't guarantee that globalization can cure a large number of these. Um And then we have to be careful with it because changing the flow in the A. B. M. Can certainly be risky and potentially lead to uh hemorrhagic events. Um So in general we we tend to offer surgery for the lower grade A. Bms. For the intermediate grade ones sort of in the in the grade three range on a scale of 1 to 5 surgery is optional and some of them um And then when they get to be um uh and eloquent cortex are are very deep within the brain. We tend to start straying towards stereotyped radiosurgery or gamma knife. And then for the high grade A. Bms in general, all treatment options have really too high of risk to warrant treatment. And sometimes for these very high grade lesions we just have to sort of watch them over time and hope for the best for the patient. So I'll show you a couple of examples of treating these. This first patient was a 37 year old who present with a sudden headache and mild left side of weakness was found to have this hemorrhage here and on C. T. A. You can see um A. A. B. M. Night is here within the right temporal lobe. When you look at this on uh angiography there's a complex A. VM notice and a draining vein here being fed by branches of the middle cerebral artery. Station also has a small aneurism of his middle cerebral artery. And when he first presented we elected to coil that with a small coil in the hopes that this was potentially one of the rupture points. Was this flow related aneurysm instead of the A. B. M. Itself. Um And then you can see another view here and then you can see the venous outflow and the later phases of the angiogram. Um We ultimately create this patient with globalization. You can see this cast of glue within the A. B. M. To slow down the flow. And then um shortly after the the embolization treatment, this patient underwent surgery and this is the A. B. M. On the surface of the brain and apologize there. My screen is skipping around and at the time of surgery we sort of just gradually dissect around the A. B. M. On all surfaces. And this is sort of a slow tedious process that takes a few hours using the microscope. And eventually after we get around the entire A. B. M. We get it to where it's uh just attached um two. It's draining vein and can cauterize and litigate that draining vein and and clip that off, cut the drain van and remove the A. B. M. On block. Uh And that can only be possible after we slow down flow with with an embolization and you can see on the postoperative angiogram, the the A. B. M. Removed. Um I'll talk briefly about Darrell Avey officials. These are slightly different than A. B. M. This is really just a 1 to 1 connection between artery and a vein. It's usually surrounding the dura mater in some way and and causing arterial blood flow into the venous sinus. Ah Sometimes we see that normal cortical veins of the brain have arterial ized flow in them and are flowing backwards from arterial is pressure from the small feeding arteries. Um And you can see a couple examples of federal officials here around the transverse sinuses. Um We have a couple of classification schemes, the board and the cone yard classifications. Um He's really differed by the beings outflow tracts, whether the flow into the beings pathways is integrated in the normal direction or as they get to be higher grade official, as the blood flow in the vein and the venus side is really going backwards in a retrograde fashion. And as that reflux gets more severe, the severity of the bureau official increases um treatment options for these uh Type one uh fish low which has fully integrated venous drainage has a fairly benign natural history and we typically observe these um uh they do have a very small risk of potentially converting to a higher grade. So we usually do put them on a imaging pathway in the future to make sure they don't convert. Um If they are causing cranial neuropathy or seizures we might treat them. But that's extremely rare to have in a Type one official to most often patients have debilitating possible tinnitus and that can be a reason that we would treat a type one. And then our options are either into vascular with an embolization, sometimes surgical ligation in very rare cases radiosurgery. The types two and 3 have a higher risk of hemorrhage. And we tend to be more aggressive with treatment. A couple of my partners doctors it full dr Chatterjee have shown that when we're seeing uh a unruptured Darryl official T. Two or flare changes on M. R. I. This pretends to be a more aggressive course and so we're a little bit more aggressive with treating these. Um And that they have been insect asia. We're a little bit more aggressive with treating them. And in general uh for the types two and 3 uh treatment benefit um versus the risk of treatment is extremely justified because they tend to be more aggressive lesions. And general endovascular is the first line of treatment with an embolization and uh sometimes we do surgery uh if uh the anatomy is not favorable for endovascular treatment or if they previously failed endovascular treatment. And then as a bailout option of all other treatment options have failed. They can do stereotypical radio surgery with a little bit less efficacy for a curate. Um So this was a patient here who presented with a whooshing noise in her left ear and also vertigo um uh really had a fairly normal neurological exam except she was a Sirat IQ and had symptoms consistent with that. Um And I went to an audiologist for the whooshing noise. This psychologist order an M. R. I. And found a very subtle vascular anomaly on the base of the middle fossa. Um that we then followed up with a angiogram. And uh I had a this Darryl official fed by the external carotid artery into the middle fossa. Um And you can kind of see this right the skull base a wrong the petrus bone on the un subtracted angiogram. Uh So this is sort of the normal anatomy of the middle cranial fossil with the middle manager artery coming out of the frame and Spinoza. And I think in this case this patient had official along some of these basil sinuses um in the middle cranial fossa. So ah because this was very close to some collateral circulation of cranial nerves. We decided to treat this with surgery. And so this was a case where we actually went underneath the temporal lobe here uh surgically and were able to find the special and and and litigated and I apologize my video is skipping around here so this is just the floor of the middle fossil with us putting a clip on the fish shallow and then authorizing it and liking and I'll move forward in the interest of time. And then the the angiogram with this um officials are gone. In other cases we do in the vascular treatment with various forms of glue or or coils into the venus pouch and that can be very successful as well. Um And really we tailor the treatment of these fish slow to to the patient. Um Again just wanted to thank you know my vascular neurosurgery team, my colleagues in interventional radiology and then our neuro ICU team who make all these multi modality treatments possible. Uh And I really think that you know uh dr Zippel said these high volume centers with these big team approaches really lead to uh the best patient outcomes. So that's conclusion of my talk and I think we've got a little bit of time for questions doctor it looks like dr Cunningham might have a question. Can you guys hear me instead of me typing this? Thank you. Thanks for the presentation guys. That was really good. I really appreciated the natural history summary for unruptured aneurysms and the phase of study. It was helpful. Let me ask something on the web if one of you can answer it. How has web changed your management of subarachnoid hemorrhage for white necked a calm and M. C. A. Two aneurysm types that usually I've clipped. I've just did my first web a couple of months ago and I've got another one with dr Moran coming up. I'm just wondering if that's if you guys foresee that revolutionizing revolution kind of a shift in how you manage the wide neck a calm and EMC a bifurcation aneurysms going forward josh wanted me to take that or you want to take it? Go ahead. Um Yes so so great question Dr um So uh yeah so for those who may not know web is a pretty new device that's been in the U. S. Really just for the last year and a half or so. Um I have to say I haven't actually changed our practice too much. Um thinking our center we probably used somewhere in the neighborhood of about 30 webs so far. I don't believe we've done any um ruptured cases I think they're probably it is going to be a tool in the arsenal quite honestly. But um you know I think as uh you know compared to some of the other tools we have um you know it requires a little bit more muscular movements inside of a aneurysm. And I my my sense is that you know I think a ruptured aneurysm is probably a little bit less. Mhm ideal target for use of a web than an unruptured aneurysm um There it's I think you know there are aneurysms that are treated acutely with things like spent assisting coiling. And I think in those cases web is gonna be a great option. But um you know clipping is a good option for FCS and occam's and I have to say those cases at least I wish you were. You know we have a really excellent neurosurgical um options. I think we still prefer to clip them when possible even before the web. But you know, I would say that I think the majority of the complications that have been reported with web have been in um Excuse me and ruptured aneurysm. So I think it's I think we all kind of want to get a little more experience before we really consider using it in a rupture setting josh. Do you have any other thoughts? I think web is gonna be great. I think it's gonna see increased use um uh And I think we will be a little bit more aggressive for you know, wider necked aneurysms with web and the ruptured setting in the future as we gain more experience. And still think that morphological e a lot of the ruptured aneurisms end up not being a great shape for the web sometimes. But there are definitely select cases where I think it's extremely useful um You know for unruptured aneurysms um You know we still are seeing a little bit of a recurrence way with web. I think that's decreasing as we're learning the sizing and appropriate use a little bit better. Um I personally still favor clipping for M. C. A. S. But in terms of something like an atomic war, a basilar icy determines the aneurysm. I think web is a fantastic option for for an unruptured aneurysm in a lot of cases and uh and a lot of ways simplifies the treatment from some of these more, you know complex stent assisted coiling maneuvers. So. Okay thanks. Are you guys using anti fiber analytics? You know patient comes in at nine o'clock. It's a good coil candidate nine PM or 10 PM. Do you use um a car overnight and then coil it at eight am the next day or where are you using? The anti fiber analytics? We're using TX a personally but yes we are using that. I think there's a little bit of controversy right now because at least one big study just came out of europe a month or two year ago suggesting that um you know maybe it didn't make a big difference if you used it and that there were you know at least some vascular complications from the anti private analytic. Um I guess the only caveat that study I would say is that their their time to treatment from presentation was extremely fast, less than 12 hours in that study. And uh uh you know I think in general we're we're hitting about that mark. Um Um but I would say right now there's probably a little bit of controversy and whether the antiviral itics make a difference if you are you know having a fairly quick treatment standard less than 18 hours after a spectacular humorous presents. So um we certainly if we're going to have any delay longer than that for whatever reason, definitely definitely still using it quite. I think the studies, I think the studies are are pretty conclusive that the the anti former olympic use in the distant past which was associated with increased incidents of a spasm delayed cerebral ischemia the short course of TX day up until the point of aneurysms. You know securing the aneurysm that's not associated with that. So I think that that has been answered I think but but but if there's other from biotic complications and whether that outweighs the benefit of re bleeding, I think that's the controversy. If that makes some sense. I just want to clarify because the old old way was TX they would be given for eight or 10 days. And then there was association with D. C. I. And but that's not the case anymore. But but other throne biotic complications. You know I think it's still an open question. And then a technical question guys I trained endovascular about 15 years ago just trans femoral occasionally we would use radial artery access if we had a you know a proximal occlusion in the subclavian and that was the only way we could get into the vertebral artery or something. But um is it just the trend? Now, is there a technical reason that maybe your catheter length is shorter? So you have more control at the working point? Or what's what's the reason for using the radial artery? The reason in general is patient safety for access site complications. And uh and and patient comfort and preference. So I would say, Especially if you're experienced criminal user radio uh cases are until you get over the learning tour, which is about 50 cases um is more difficult and challenging than it, I think becomes kind of second nature. And you don't know much of a difference with interventions between radio and ephemeral uh in terms of length, it's negligible because you actually need about the same length of tools from radio as femoral. Um And if you think about it, if your your wrist drops, it's right at your growing level. Um And so the length is about the same. Um But, you know, from, from the cardiology literature, they have multiple large scale randomized control trials with thousands of patients in them that clearly show that access site complications are far less with radio. Um And then in terms of uh you know, cost and and patient preference that's also been shown to benefit radio, you know, significantly as well. Um So we really do it for for patient comfort and and uh in a lower rate of access site complications. More so than any sort of technical advantage. How big of a sheet can you put in the radial artery? That's probably a little bit size dependent. Um ah The bigger the bigger ships you can really put in uh up to uh you know, an 088. She's like a, you know, a shuttle or neuron max or ballast or striker infinity directly in the radio. And in most patients who have a radio greater than, you know, a millimeter and a half in size by ultrasound. Certainly the bigger you go um The higher rate of radioactive conclusion you're gonna have um the cardiologist has certainly shown that radio artery occlusion is basically negligible consequence that doesn't result in any sort of hand ischemia or anything like that. So um I would say, you know, uh for all radio access, there's about a 2% risk of radio artery occlusion. If you're putting in something larger than seven French Um that goes up to about 5% per case of radial artery occlusion. Um But you can absolutely fit it in for the case and use it for the case and you just might not be able to re access the radio artery for a second case if you go really big. But pretty much at this point if I can stick the artery and get a wire in and I'll put any size devices, I'll add some, you know, josh husband like introduced this practice into our group and where we're fortunate for that I kind of initially adopted more of a look and see kind of you know kind of see how things shake out approach and gradually adopted more gradually adopted radio in my practice is now but I do about equal numbers of cases both ways now. Um And uh the one thing that is very very clearly in favor of radio is like those outpatients when you do this complex case in and all they remember is that they had to lay flat for two hours because they had back pain. And those patients going home and getting to move around and going home an hour after the case is actually they really appreciate that. So I have you know that's not everybody but I have quite a few patients who seem to have you done it the old way they like this for an approach. And then in terms of the the size of the catheter. Again, the largest I've ever put is in uh you know a catheter. But I also find that you know for the right patient you actually need less support from a radio access approach just because the vessels are smaller. And uh kind of the vessel itself gives you some of the support you know that in the straight for um you know you can get away without a B. M. X. 296 or something like that. Thanks a lot