Welcome everyone to ClearPoint On Demand. Thank you for joining us for our first webinar of 2024. I'm Kara Kittelberger, the Director of Education, and I'm delighted to introduce our speaker for today, Dr. Mark Richardson. Dr. Richardson is the Director of Functional Neurosurgery at Massachusetts General Hospital, the Charles A. Pappas Associate Professor of Neurosciences at Harvard Medical School, and a Visiting Associate Professor of Brain and Cognitive Sciences at MIT. Dr. Richardson has performed hundreds of procedures utilizing the ClearPoint system throughout his career. Given the depth and breadth of his experience in this space, we're very excited to have him here today to discuss how our new ClearPoint Prism Neuro Laser Therapy System has impacted his clinical practice. Please join me in welcoming Dr. Richardson. All right. Thank you, Kara. Thanks to ClearPoint for sponsoring this webinar. You're seeing my screen okay? Yes. Yeah. All right, great, thanks. So, I think many people that are tuned in are kind of aware of my long-standing use of the ClearPoint device, and I've really been working with this company since I was a resident at UCSF. So I'm pretty biased towards the use of the system, but I am, in particular, very excited about this Prism system that we've started using at MGH. And so I'm gonna run through some highlights of our use in the first several cases here. These have been for epilepsy, but also a couple ablations for OCD. And tell you about some of the features of the system, and also just show a couple examples from cases so you can see the difference in imaging quality, which is really huge. I think one of the major differentiators of this technology, compared to what we've been using. So it's not gonna take a ton of time to go through the slides, and I welcome what questions you have afterwards. So this has been my take on LITT, that it is really promising, but the technology itself hadn't progressed too much. And it's really important that technology does advance in order to get better outcomes, so that we can bring our LITT outcomes closer to that of resection, to really make LITT function like a virtual resection, which is the goal. Okay, so I think these are the main reasons, in my opinion, that have limited the use of LITT and maybe our outcomes to a certain extent. So that's poor background imaging. I found it on the two systems that existed prior to Prism. I've always been frustrated with the background imaging, signal dropout, disjointed workflow. So certainly in the environment where we use ClearPoint in the MRI for laser probe placement, and then transitioning to another system that has always felt clunky, of course, it can work fine. And delayed thermal information, so I think this has been one of the limitations, at least in my hands, especially for small lesions like hypothalamic hamartomas, and doing ablations that are close to eloquent cortex, is that in some cases it can be a little dicey with the refresh rate. And so the refresh rate on the Prism system is much improved, and we'll talk about that. Okay, so I've said this, that I think it's important for us to improve outcomes, and I think this new technology is going to help us do that. The laser technology here really is next generation, and that's primarily because it does not involve cooling. So the applicator tip is made of fiberglass, and it has very efficient heat transfer. So the probe itself does not get as hot. The heat is transferred to the tissue in a very efficient way that does not require cooling, and this has a number of advantages. So one is just it's more efficient to deliver energy into the tissue. You can have shorter ablations, delivering the same, actually more energy for the same ablation size. And it's a misnomer that because it isn't cooled, the tip itself is hotter or more dangerous. That's not the case. It's about the efficient transfer of heat into the tissue. This is, I think, a big one. When you don't have to introduce a cooling component at the tip of the laser, you don't introduce this artifact problem and the potential for signal dropout. So sometimes we have cases with the Visualase or Monteris systems, and I've used both. I mean, just to give you some background on where I'm coming from with this, when I was in Pittsburgh and we started doing laser ablation, we trialed both the Visualase and the Monteris systems, and we ended up installing the Monteris system. When I came to MGH, and now this has been five years I've been here, the Visualase system was in place. We started using the Monteris system, and then when we trialed the Prism system, we decided to basically just stick with this system as our single system. And this reason was a big reason for me, which is the signal dropout is almost non-existent. We've had one case where we had a little bit of dropout around the laser probe, but that's it. I'll show you some images. So this is the sort of thing that we're used to, and this is, you know, maybe not as big a deal as in other cases. This is a previous NeuroBlate case. And, you know, we always see this dropout around the probe itself. And depending on where you are, this is not a big deal, or sometimes it is a big deal. The smaller the lesion, the bigger a deal this is. Also the location is important. So this is a, this is another NeuroBlate case where we wanted to do an ablation. This is an SEEG confirmed, MR non-visible lesion. This is presumed FCD, and this was confirmed by stereo-EEG, an epilepsy patient, a mesial orbital frontal/basal frontal ablation. So near the skull base, and that was the, you know, excuse for having signal dropout. And it's just difficult, I think, to know exactly what you're doing safely, and you have a choice here of just blast it out or be conservative, and not go beyond the imaging that you have available. And we had. I think this is the example of a case that failed with our initial approach at laser ablation, and there was just not an adequate ablation. So that can happen for a number of reasons, but I think, you know, signal dropout can, can be an issue, for sure. So other advantages to this system, without the cooling, there are less points for failure, which is important, and it reduces overall treatment time. So the ablations themselves are faster, heat transfer is more efficient. This is also a big deal. The refresh rate is about three seconds. The Monteris system is slightly under eight seconds. The Visualase system is around five seconds. So this is faster. And this is another big deal, which is the imaging resolution. So this is definitely best-in-class, sub-millimeter in-plane resolution. I'll show you some images. This is one. This is a very small hypothalamic hamartoma, and you can see there is no dropout in the area, represented by the thermometry signal, which is the tip of the laser fiber. This is critically important for these small lesions. The ThermoGuide is the name of the thermometry software, and so there are four thermal damage thresholds, or TDTs. Unlike some of the other systems, these are represented simultaneously, so you don't have to switch between different lines that you're following. CEMs, cumulative equivalent minutes at 43 degrees Celsius. So yellow is, you're concerned that tissue is gonna be damaged for good. Orange is, cells are gonna be dead within 48 hours, and red is, immediately, irreversible damage. ClearPoint did do the analysis to match the ablations to histology in large animals, and this is part of the data submitted to the FDA for their FDA clearance for this. But it's important, I think, to show this and to acknowledge that this very sharp drop-off that you would expect like we've seen from other groups who have done this in animals that this is the case for this system as well. You can set up to seven temperature guards. I frankly don't use these that often, but they're there. One thing that's important here is this automatic phase drift compensation. This, in theory, should provide the most accurate thermometer readout because it's trying to account for real temperature. And so the way this is done is better than that, the methods that exist on the other systems. The Visualase doesn't correct for that, and Monteris does this at a lower resolution. Okay, so especially if using the ClearPoint navigation software and you're doing this, you're implanting your probe in the MRI environment, this workflow is very efficient. So this laser fiber is inserted through the peel-away sheath, and for those who do DBS with this method, it's very similar. Or maybe who've done... for DBS, it's very similar. This is. I pause for a second because this is the Array tower, which is more stable to streamline version of the regular G-frame tower, and... We'll show some examples of how the different trajectory openings can be used that are part of the Array system, but you don't have to use that. So I'll show some examples, two cases that were done with multiple trajectories, the same burr hole, and also an example of one where the tower was aligned and we drilled, you know, in an offset position and did two trajectories percutaneously. Here's a fiber. You can just test that it's intact by sending some regular light through. And this is Pranav Nanda, one of our residents. He's getting ready to remove the ceramic stylet. We've verified that. We verified the stereotactic accuracy of our trajectory, and then we're going to insert the laser fiber down the peel-away sheath after the ceramic probe is removed, pull back the peel-away sheath a bit, and do the ablation. And you can see this is a, is a flexible laser fiber. This particular insertion, I think this is—this may be a, a hippocampal ablation with a posterior trajectory, and so we have an MRI environment at MGH, and so in this case, we would have moved the magnet back, inserted the laser fiber in, and then moved the magnet again for scanning. But we've also had some cases that are, let's say, through a trans frontal approach, and this can all be done by just reaching into the magnet. All right, so the laser fibers are all small diameter, 1.7 millimeters. This is the operating wavelength, so greater tissue penetration, so this is a high wavelength. There are three laser window sizes: 1 millimeter radial tip, and then these 15 and 25 millimeter diffuser openings or windows. These are the estimated ablation ranges, so you can see if you're someone here who's interested in this for a tumor, you might be more interested in the 25 millimeter diffuser. And the expectation is that you can get the largest ablation possible from any of these systems with the 25 millimeter fiber. We mostly use the 1 millimeter and the 15. Okay, so let's get into some examples of how we've used this. So a couple of cases where we've done multiple trajectories through a single burr hole. So essentially, we've made a burr hole, standard 14 millimeter burr hole. We mounted the SmartFrame on top, and this is a cingulotomy that we did recently. So in this scenario, there are two SmartFrame towers. We would align the left side, then the right side, drop the laser fiber on one side, do the ablation, go into the scanner, pull it out, drop it into the other side, which is already aligned. Measure the ablation, you know, with a scan, and then align for the second trajectories and align for the third trajectories, and do that in the same fashion. So let me just point out a couple of things here. One is the background image. So this is the actual image that's used during the ablation on the left. This is a representation of the ablations when the scan's been pushed back into the ClearPoint planning station. This background imaging is really, really good. Now, if you're looking at this and you're thinking, "Well, I don't think that's a big deal," then you definitely figured out at your center how to do better background imaging for Visualase or the Monteris system than we did. This is order of magnitude better for us, and this increases confidence, in my opinion, you know, dramatically when the background imaging is what we'd expect for any of the other stereotactic planning surgeries that we do. So this is a representation of the ablations. This is there, and you can see how it matches up here with the contrasted signal. Okay, here's an epilepsy example, also multiple trajectories through a single burr hole. This one. Oh, let me just say, this was the 15-mm diffuser window, and it was about 15 mm from the corpus callosum up into the. It was really 15 mm past the cingulum here, so we have some ablation above this too. But that's the size used in this case. This was MR negative, SEEG-confirmed anterior insular seizure onset zone involving the short gyri of the insula. Here are our trajectories as planned on the ClearPoint, so we had an anterior trajectory and then a posterior trajectory. Oh, I put this in here, you know, for those who aren't maybe using ClearPoint regularly, this is something that we just take for granted now, which is the error. And we always expect the error to be under 1 mm. It's the same thing for our DBS cases. It is really, really rare for us to have error that's above a millimeter. So it's a nice result for this case and very important for a target like the insula when you're doing an ablation. So I'll just point that out for those maybe who are less familiar with the system and how accurate it is. We use two different laser fibers here, the one millimeter radial and the 15. So in the anterior trajectory, this is the one millimeter, and we did a pull back, and a pull back, and a pull back. Oops! And you can see this is what the ablation looked like. And then I thought, "Well, wait a second, why are we doing this? Why can't we - let's just put down the 15 millimeter." We are more comfortable with how this works, and, you know, we had confirmed that the post-ablation scan kind of matched our expectations. So we had more confidence in just using the 15 millimeter, and in fact, that gave a nice ablation here. Okay, so this is a very interesting case. So this is one of these cases, it's a scalp-negative EEG. A guy who had been told... A young guy, an econ grad school student who went through years of people not believing he had seizures... Long story short, we did SEEG and sure enough, he's got insular seizure onset. So he's been seizure-free now for several months after this ablation. Okay, you can also align and do trajectories, multiple trajectories without realigning. The way that you do that is with this offset instrument that is inserted in the Array. And it has different offsets here that can be visualized on the software, and I probably should have put a slide in to show how that works if you're not familiar with this device, this version of the device. So we're able to do an initial trajectory, and then to choose which offset we'd like to do a second pass without realigning the frame, and so we just move. This is like, if you ever used the FHC system for microelectrode recording, it's a kind of similar thing, but nowhere near as complicated as the FHC system. You just take it out and move it into the position that the software tells you. And here's an example of what this looked like on the scalp. So we're able to do 2 percutaneous entries, basically just drill right through the skin and the bone and even do this right next to each other. And the reason we did that for this case—so this is another case, and a couple of these close together, where again MR negative, but SEEG confirmed mesial frontal onsets of basal frontal mesial orbital frontal areas. And in comparison, if you remember that screenshot that I showed before, that had a lot of signal dropout along the skull base. Here, there's none. And although you can't see it in the screenshot on the left, on the right, you can see that there's already some signal kind of to the left of our thermometry reading, and that was the initial trajectory. Rather than realigning, we just needed to get more of this area, which we could do. We had actually planned for this ahead of time to how we could fit 2 trajectories in with one alignment. So that's what we did here, and you're seeing the ablation there. Okay, so that's it. That's the overview of all the high points. We didn't want to take up too much of everyone's time, and I'm happy to answer any questions you have. Thank you, Dr. Richardson. If anyone does have questions, please feel free to enter them into the chat box. I have a couple to get us started, but again, at any time, please feel free to type those in. So, someone wants to know: In your experience with the non-cooled laser, have you seen any higher incidents of charring or other adverse events that you're concerned about with the laser fiber system? No. We haven't. So we haven't, for instance, seen any tissue stuck to the laser probe or anything like that, that would indicate, you know, physically that there's an issue. And we also haven't had any surprises on our imaging. So I think if, yeah, if there was some concern about, you know, basically getting too hot or charring the tissue, we would end up with a lot of edema in some cases, or a signal that was, you know, not, not consistent with what we had seen on thermometry reading, and we haven't had anything close to that. Right. Any tips or hints for how to get a hospital to approve this system if another company is already on site? Yes. So, I think it's a safety issue. And hypothalamic hamartomas are a great example. I think based on my experience so far, it's easy to make an argument that there's really an order of magnitude difference in safety in terms of being able to do an ablation of a small target in an eloquent area, and there you have mammillary bodies. And so that, that's one example, but... So getting to safety, it's the refresh rate, the background imaging, and time. So it does save time. There is an advantage to the integrated workflow, I think, if you're already doing placing your laser probes in the MRI environment. The hospitals tend to like having one system, you know, to do things, so there are less vendors coming in, and that was a selling point for us. I think the key is to just get permission to do the trial. That's the key. So I would push it through on the safety, which I really believe. I mean, I'm much more confident using this system than with the other systems, because you can see what you're doing, and the feedback is faster. In your experience, are there time savings that you have performing the procedure with the Prism system compared to other systems? Yeah, I think there's you certainly save time when... because it's more seamless to transfer from the ClearPoint planning to the Prism, and eventually that's gonna be integrated as a new system, kind of into a more integrated system is my understanding. So I think there's an advantage for planning to that, planning for that. The improved background imaging, I think, has saved us time, because previously with the other systems, we'd say: "Oh, this is, you know, we can basically see the structures, but not as well as we'd like to." Do we need to re-scan? So then we re-scan, we try to improve the background imaging. It doesn't improve that much. We're trying to pick different points so we have less signal dropout, and so the futzing around that comes with trying to have a higher quality imaging adds time. So yeah, I do think the ablations are faster. The ablations are faster. But I think the biggest thing is removing the worry and playing around with the scans or trying to get the imaging better, because you do a scan in, and you basically got it. Now, the caveat is, we spend a lot of time optimizing the scans, but once you have it optimized, you're in good shape. Are you using the SmartFrame Array for all of your LITT procedures? And if so, is the primary reason due to the lower profile, improved stability, or the parallel multiple trajectories, multiple reasons? We're using it for multiple reasons for both of those reasons. The main one is stability and just the fact that you don't need all the other bells and whistles that are in the full stereotactic software like you would for DBS. So you don't really give anything up by using the Array, and it is more stable. And if you... Let's say you have some reason to switch between doing a burr hole or drilling through, you know, on the day of surgery, you realize something you hadn't thought of before, you wanna have some flexibility there. If you plan for the Array, you can, you know, you can use both techniques. So I think those are the main, main reasons. I was a late user of the Array up until recently, and so I think we wanted to gain some experience with it, too. We've been happy with it, but the main thing is stability. Can the system only be used with ClearPoint Navigation? My understanding is, what is my understanding? Yes, now it can, but so... That's not true. So if it can be used with any navigation, so any way you have to align to put your laser in, you can do it. There is not a built system that's made by ClearPoint that's currently FDA-approved, but I understand that that is in process and is likely to be available. How do you feel the damage estimation accuracy compares to your experience with Visualase or Monteris? This is a great question. I think it's superior. We've had one case that I have not been satisfied with, with this system, and it's the one hippocampal ablation that's happened to come through since we've been using the system. I think we've been using it now for, oh, how many? Six months, maybe. Is it longer? It could be slightly longer than that. Just had one hippocampal ablation come through in all that time. And when I went back and looked at that, the signal matches up well. The issue is the trajectory, and, you know, not making a big enough ablation of the trajectory itself. So in all the other cases, we've been, you know, we've had a good clinical outcome, and I do feel like it's more accurate. In your experience, do you need to use the maximum power to achieve a 20-millimeter ablation? And if so, do you run into the 85-degree Celsius limit that's demanded near the probe? Yeah, I don't know the answer to this question because I haven't had a reason to try to drive out. I have not ablated any tumors, and to me, this sounds like a tumor ablation type question. So I don't know the answer to that question. Are you using a 3T or a 1.5T, and have you noticed any of the equipment having any ferrous properties? We use a 3T. That hasn't been an issue at all. I don't have experience with this system on the 1.5T. When I was in Pittsburgh, we did all the cases in a diagnostic 1.5T scanner, and we're, you know, obviously very pleased with, with how that went. But for Prism, I only have experience in the 3T. Do any of the advantages. With no issue. Oh, sorry. Yeah, just to make sure I answer the question, yeah, no, no susceptibility, you know, issues in 3T. Great. Do the advantages of Prism that you've discussed increase the number or types of patients that you'd be comfortable treating with LITT? Yes, I guess my approach is, I haven't shied away with the existing systems from treating lesions that I felt were difficult. The main difference is the level of confidence. I just returned to the hypothalamic hamartoma, where I brought back a patient who had failed a small hamartoma, gelastic seizures, kid, 10 years old, small hypothalamic hamartoma. With signal dropout with the Monteris system, I had driven up the ablation to the extent I felt was safe, and in that case, I didn't have any idea whether that was gonna help the kid. He was seizure-free for a little while, then the seizures came back. We brought him back to redo the ablation. There's just such a large difference because you can see everything so much better. So that's, I think that answered. I think that covers. I'm not sure I know a little bit about your practice, although I haven't covered your case in a while. So someone wants to know, using the Prism system, are there any advantages that maybe address some of the problems that can be encountered with thermal MRI artifacts in cavernomas? Hmm. Let me think about that for a second. Thermal artifacts in cavernomas. You know, I haven't ablated a cavernoma. I've resected every cavernoma I've come across with that, you know, surgery was a surgical case, so I don't know the answer to that. You might not know about this 'cause I know your clinical specialists take care of it, but do you know anything about how similar the protocol or sequences are to what's used in comparison with Visualase? Do you need any special licenses on the scanner? Aha! I think I can answer the basics on this, but you can fill it in if this is incomplete or incorrect. Yeah, that's the answer. Kara, is that correct? Yeah, you don't need anything special beyond what you already have. Yeah. And what we have is pretty basic. I don't think we have anything terribly sophisticated on our MRIs, from what I can tell. Based on some of our other requests are outside of. To purchase. Yeah. Your ground truth for post-op imaging. Are you using contrasted scan, FLAIR? What do you find kind of holds up best over time? Well, we need to build our experience with this system, in particular, to give an honest answer for that in terms of over time. But I think the contrast enhancing scan is the one that really shows the best potential for damage. We get a FLAIR, and we get a contrast enhanced scan. But just in general, with ablation, if I don't see a good contrast signal, then I'm worried that, you know, that's not a full ablation. And so I will say, what I've learned from switching to this system is probably that fact exactly, which is when you've... In the other systems, again, at least in my hands, for some of these cases, so sometimes there's no issue, and depending on the target, you do a big ablation, and you know it's you did a great job, and it's no problem. But it's the, it's the cases that are kind of borderline, where you push the thermometry signal out to what you're comfortable with. There may have been some signal dropout. The background imaging wasn't great. And then you get your post-ablation scan, and there's some contrast enhancement, and there's some FLAIR, and it looks like, yeah, that maybe that will fall then, and be an adequate ablation. But you're not gonna do anything different anyway because you already pushed the system to its limit. That's, I think, one of the big differences here. So in that type of scenario now, if I do the imaging with the Prism system, and there's not a good contrast-enhancing signal, what I would do is, I would go back and look at the thermometry images and see, okay, were we really at the limit of where we thought it was? Is there something more we can do here? Because we can, we have more confidence in the representation of the thermometry. So I would say if there was, if the lesion didn't look adequate, I would think, maybe there is a mistake in my interpretation of what we have done, and I would go back and look and have a lower threshold for doing more ablation. That's great. And somewhat related to that, another question: How does the post-ablation edema compare to systems that use a cool fiber, and do you manage it any differently? Yeah, I don't think there's any difference here at all. So I think there are two things that I think are the main take-home points about the absence of cooling. One is there is less signal dropout. It's almost non-existent. And two is there's no cooling because the heat transfer is just more efficient, which means the ablation is done faster. It's not that you're cooking the tissue the same amount of time, that you have the same amount of time and just more energy is going in with the Prism, and you're really frying everything. The kind of end result is gonna be equivalent to what we're used to. The differences are the efficiency of getting you there and the confidence in seeing what you're doing. I haven't had any reason clinically to think that there is an increased Edema problem, nor have we seen that on the imaging. Does, uh. So my standard thing. Sorry, Kara, just real quick. My standard thing is a one-week steroid taper for these patients. And that's mostly for headache, for anything that's close to the dura. So that's my standard thing. And even, you know, I try to, as many of these patients as possible, these laser ablation patients, I try to do them same day if they're willing, to just let them go home same day. When you're using ClearPoint navigation, does that allow you to change your plan or react? And how do you adjust your plan if you feel you need to do more? Okay. If you are using so the answer is yes. If you image and you leave the laser fiber in, you can just turn it back on. You can pull it back, and you can obviously make minor adjustments along the trajectory. If you really want a new trajectory, then you have two options. If you have made a burr hole, then hopefully you've already accounted for the fact that you might want to make another trajectory, and you'd pull the laser fiber out. You'll go through your basic realignment steps in the ClearPoint software, and you'd get to a new trajectory that you had planned. You'd be aligned, and then you would insert the ceramic stylet, verify that that's in adequate distance or spatial relationship to your initial ablation. If it was, you need to insert the laser fiber, and you'd ablate again. If you did not make a burr hole and you had planned to use the offsets, then you wouldn't have to realign. You would just look in the software down the different trajectory views of the offset to see if one is appropriate to increase or extend your ablation. If there isn't such a trajectory, you still have the option of realigning. You just plan a new one on the software, and you can realign, and then you can have that Array of options, you know, available with the new align. I'm gonna reword this question slightly, but I think what they're getting at or wanna know about is, do you have any issues with everything kind of fitting within the MRI bore? And is there anything that you need to do to adjust that, or are you able to kind of plan ahead for what needs to fit within that confined space? Sorry, can you just say that one more time? So I think the question is regarding, you know, you've got the patient in a certain position, the SmartFrame, and then, you know, the laser fiber, which is flexible. You know, how do you fit everything in the MRI bore? Do you have any issues with bore collision? Yeah. It is possible to have issues with bore collision, mostly with the ceramic stylet insertion, because that's not flexible. Having said that, the key is large bore, so if you... Which is 70 centimeters. If you have less than that, then you may have some issues with some of the cases. If you have a large bore, you're gonna be good for most anything. If you have an IMRIS or some other MRI that moves, you're never gonna have an issue because you can always move the magnet out and do an insertion. And then once you've done the insertion, the profile of the system is low enough that it can be accommodated. So short answer is, it's actually pretty rare to have collision issue. They can work around. Have you seen any regions of signal dropout where a biopsy had been performed? I haven't done that, so I don't know the answer. Again, I'm not. Basically, I'm not doing tumors in this, you know, in this environment. Just, that's not my practice, so I cannot answer that. How much of the preparation and completion of your LITT cases are done in the MRI environment, and how robust is the ClearPoint system to drill through for the multiple trajectory cases? Well, basically, so in the MRIs, the bone work and the drilling is done with the magnet in its you know, in its warehouse behind closed doors, so we can use all regular instruments. And then in terms of how robust the system is to drilling multiple trajectories, that's very robust with the Array. You can do it. We have done it with the frame, but the Array is pretty stable. Now, I always recommend scanning to check again. You know, we don't assume that we didn't move the tower. We rescan after drilling to be sure, but it's pretty robust. Any suggestions for achieving, maximum potential ablation width? Yeah, I think that just, that's really about planning of the trajectory and safely avoiding heat sinks to the extent that you can. And I think that's the same for any system. So if you really wanna make a maximal ablation, you need to be able to safely, safely, you know, crank up the wattage, but also crank it up in a way that it's not gonna be released into a heat sink too soon... you know, meaning like a sulcal boundary or some other CSF boundary. Where does LITT fall into your protocol for epilepsy after diagnosis? And do you see a potential for expanding indications with the safer laser system? I think the thing that drives increased use is better outcomes. Where this falls in our practice is for lesions that are small enough and deep enough that it makes sense not to do an open craniotomy as the first maneuver. In cases where you can really see the target better. I mean, I think the insula is a good example of this. Some of these basal frontal lesions are a good example. I think the most, you know, really the most important thing is getting a good outcome without having to come back and either do another ablation or do another surgery, because that's what convinces the referring neurologist that it's a good idea. They're often the ones who, well, not often, they have plenty of patients that could be candidates, and they may have biases to whether or not this is gonna work. So, the more, the better our outcomes, the more referrals we should have. I think that's. I think the system would provide better outcomes. Yeah. Better outcomes, more referrals. That's, that's the end of our questions. So thank you, Dr. Richardson, for your time today. I know you're very busy, and we appreciate you sharing your experience with us here today. Okay. Thank you. Thanks for everybody's time. Thank you.