Dr. Roger Sur
Appearances
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
We know that TURBT procedure is critical in the care of patients with non-muscle invasive bladder cancer. With data that shows that CIS was missed by TURBT in more than 45% of radical cystectomy cases and 86% of residual tumors have been found at the original resection site, it's clear that enhanced visualization could be a significant benefit during TURBT's.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Yeah, with the 1.0, it was like that. With the 2.0 now, we were just literally as you're lasering, you see the fragments just coming across your screen, collecting to your little container attached to the scope. And then when you want to really turn on the suction, it has this spray, a very proprietary spray action that comes out from the scope.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
It's different than just irrigation coming out of scope. There's multiple sprays coming off the scope that surround the stone and bring the stone back to the scope. And then it's got a seven French channel that you can evacuate large fragments through the scope.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
It was initially homegrown. I had to learn the hard way, truthfully. I didn't realize that everything I do in the university is owned by the university. So that initial patent that George and I spent a couple thousand dollars on, that really wasn't very useful. That's a nice write-off for us. The university's like, no, you have to go through us. So we had to go through them.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
And then once that was patented, we did a roadshow and tried to find some investors and got some initial seed funding for that. And then the company was formed.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Venture capitalist type funding is how it came from. It wasn't a government or anything. It was a venture capitalist funding. No SBIRs or anything like that? No. I did not go that route. I just went on the road trying to pitch it to investors or angel investors looking for someone that was interested. And I had some different people and finally stumbled upon someone that saw eye to eye and
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
they were very student actually the questions that they asked it was very impressive meeting these people they're not just business people they uh they know science so i was actually shocked by how you know how well they understood the science
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Yep. Constant irrigation, constant aspiration or suction. And then if you want to turn it on to high power irrigation, you've got that spray that comes out. And then the high power suction where you really turn on the vacuum. So there's two levels to it, the aspiration and irrigation.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
It's going great, Aditya. I'm really honored to be here. And I'm glad you're my host, actually, because it makes it super comfortable for me since we're good friends.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Well, the problem is the current retroscopes that are out there, the working channel is a channel that's shared for irrigation fluid coming in, the basket or the laser that you're using, some working device. And then if you want to do what you're describing, then you'd have to... temporarily stop the irrigation and then pull back, right? And you think that would work.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
But two things we've learned is number one, the channel is not very big. 3.6 French is only 1.2 millimeters in diameter. So your stone bear be smaller than a millimeter, which is pretty small. And then two, kind of like a balloon or when you're emptying the bladder, you're e-licking the bladder.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
If you don't have enough irrigation, the whole eclecticism collapses down onto the device, much like you're doing an e-lick and you have not put in enough irrigation into the bladder, right? You don't get anything back. It just collapses down onto your scope. So that's really the problem that we've discovered. Got to have a balance. Yeah.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
And that's why having constant irrigation and constant aspiration is really, I believe, a game changer. Because it's kind of like having a continuous resectoscope. And imagine you had a resectoscope, but suddenly someone introduces, how about a continuous flow resectoscope? Not just...
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
A resectoscope where you have to kind of, you know, when you want to aspirate, you have to take apart the scope, which was the old scopes, right? Like, wow, yeah, we'll do both at the same time. And then we'll attach a little suction to the outflow so you really get some aspiration. So that's kind of the best analogy in my mind is what the CVAC device is like.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
It's like a resectoscope, so to speak, in the ureter.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
I would say currently on the market, there are three predominant devices that exist. The CVAC system, which uses the steerable uroscopic renal evacuation. We call it SURE. That's the name of the procedure, the CPT code that's associated with it. It's not just ureteroscopy. It's actually called steerable uroscopic renal evacuation. That's the code you use when you use the CVAC.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Now, there's two other devices that don't use that coating. There's the FANS, which is Flexible and Navigable Sheath, which uses basically, it's like ClearPetra is the big maker in the United States. It's actually a Chinese company, but that's probably the most common device that's used here in the United States. And then there's Direct In Suction Scope, DISC.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So those are the two other devices that exist right now that you can consider if you're not going to use a CVAC. And what fans is basically, it's an axis sheath, but it has a side port where they're actively aspirating. And you can actually regulate the amount of, not aspirating, but you're vacuuming. They attach a suction tubing to the side port. It's kind of like a Y coming off the axis sheath.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
And you attach it to a suction tubing, which goes to the wall. And you can actually regulate the amount of suction. And the beauty of this device is axis sheaths are 10 French in inner diameter or 12 French, depending on how big of an axis sheath. So you can really remove large fragments. What you have to do is you break up the stone.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
and then pull the scope back and use that kind of vortex phenomena. You've seen it. As you're pulling the scope back and the irrigation is going, the stone just follows the scope back. And of course, if you have a vacuum attached to the side port of that fan's device, then you're just sucking all these huge fragments out.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
and they now have a 2.0 version where they found that, you know, just sticking access sheets up there, think about it, it's not very maneuverable, right? What if a stone's in the lower pole? Well, they recognize that and they iterated where they made the last 10 centimeters very flexible. So you can pass your scope into the lower pole
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
pass the axis sheet over the scope and now the the axis sheet is in the lower pole and then you can break up stones and remove the scope back and forth back and forth to remove large fragments and also while you're dusting there's also fragments coming around the scope as well down the axis there's there's two ways that the fans device removes stones small particles going around the ureter scope
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
and then large pieces coming down as you pull the entire ureteroscope back.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So imagine a ureteral axis sheath, but then at the portion where you put your scope in, there's actually a suction port that attaches to it, kind of like a Y. So it's coming at the same channel irrigation.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
And that's how that functions. So the last one is the direct in-scope suction. This is kind of what you had kind of alluded to with your first question. Why can't you just take a scope and aspirate back with a syringe? And shouldn't that be good enough? Well, as I described, you know, you have to, it's one working channel.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So what they did was they basically took two stopcocks and they attached them side by side and attached it onto the working port. And that's what they have is direct in-scope suction. Through one stopcock, they're irrigating and through the other stopcock, you can aspirate. But one of the limitations here, the working channel is still 3.6 French. You haven't changed anything.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Unlike, you know, fans where it's maybe 10 French inner diameter or 12 French, depending on your axis sheath, or a CVAC where it's 7 French, you're still using your standard ureter scope. So the working channel is only 3.6, so you really have to make dust if you want to use discs. And it's not continuous, unlike CVAC, which has constant irrigation. This is you have to either aspirate or irrigate.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
You can't do both at the same time. But it seems to be an economical solution, but limited by the fact that you still have a tiny channel that you're working through.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So you basically have the camera, you have a separate irrigating channel, and then the third thing that exists is that seven French suction channel that you're aspirating. And through that seven French, you can put a laser through or remove the laser. And when you remove the laser, With the laser there, you're getting parts coming through, but the laser is kind of there.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So it's, you know, you don't have the full seven French volume or size. So if you want the full seven French, you have to remove the laser fiber. And now you've got a full seven French size aspiration channel. So what I'll do is I'll start the case and I'll have the laser in there. I'll break everything up into what I think is about one to two millimeters, remove the laser fiber.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Now, a lot of the pieces actually have already gone. While I'm just dusting, they're all just sucking into the little, I can see it going to the canister, the tiny pieces, but there's still some one to two millimeter fragments that are left behind. So I'll remove the laser device
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
then aspirate or irrigate full force and then engage the uh the lever and i get full uh very high volume aspiration all the larger pieces and come flying through the seven front channel i wish i had a picture for you here but i hope that makes sense no i intentionally didn't look it up so i could try to explain it without having or you know talk about it without having preconceptions
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Yeah. So the overall is a 12 French or 11. It's a little under 12 French. It's 11.9. It's not tiny. And this, I would say, is one of the disadvantages of the CVAC is it requires a 1214 French access sheet. And not every patient is going to accommodate a 1214 French, right? I'm sure you put up a 1214 like it's not going to go. Well, in that case, you can't put the CVAC through.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Now they do have a get around for that. If the 1214 doesn't work, they have a, you can just use the scope by itself. It has an obturator kind of like its own access sheet. It has an obturator that goes through the seven fringe working channel and you literally pass over a wire, the entire CVAC with the obturator over a wire into the kidney.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
But again, if you have a really tight ureter, it's not going to work. You have to pre-stent the patient or just do standard ureoscopy with your normal ureoscope. But an 11-13 wouldn't work. Oh, 11-13 would not work with the CVAC, yeah. And you could say that's an advantage of the fans is that you don't need a 12-14. They have 10-12. They have different sizes. You can use your own ureter scope.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
I will say with fans, one of the disadvantages potentially is think about the wear and tear on the tip of that ureter scope. You're going back and forth, back and forth. You can imagine, you know, a lot of these reusable scopes, they last, what, 10, 12, 14, 20 times, and then they break down, and you send them off for repair.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So you might want to consider using a single-use scope if you're going to use the fans to avoid the wear and tear on your standard reusable scope.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Yeah, these are all the different... As far as cost goes, I think what you're alluding to is what's the price and what am I getting for it, right? And each of the devices has its advantages and potential disadvantages. CVAC, you're not using your scope. It's a single-use scope, so you're not using your...
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
standard wolf or your olympus or carl stortz flexible ureterscope it's its own single use scope it's one and done um so there's no wear and tear on your scope and then with fans you could use a reusable scope but you probably want to consider using a single use scope so you're not wearing tearing on that and then this you've got to use your reusable scope with their attachment
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So across the board, one thing has been clear, and this came out in a systematic review, that the use of suction devices, just broadly speaking, achieves two things. Number one, higher stone-free rates, and number two, lower infection rates. So irregardless of what you're going to use, Adidia, you're going to achieve potentially an advantage there. So I think that's nice.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
We've moved the needle forward that, look, we're getting better stone-free rates and lower complications. Now the question is, well, which of these devices is better, right? Which one achieves better stone-free rates? Which one has less, reduces morbidity more? And the problem is we don't have comparative trials. I will say the CVAC, we do have that. We have a multi-institutional Aspire trial.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
It was made up of 11 institutions. And their 30-day results demonstrated benefit of a higher stone-free rate for the CVAC over ureteroscopy. It was a comparison of just standard ureteroscopy basketing versus CVAC. And the CVAC appeared to be better. This is the 1.0, not the newer one that we have out there. But we don't have a CVAC versus FANS versus DIS study to date yet.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
I will make one other comment here. What was very interesting with that ASPIRE trial that I'm talking about was we just published, or we're about to publish, we presented at the World Congress, the one-year data of this. And what they demonstrated was that by using the CVAC 1.0 device, they significantly reduced post-operative events.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
I thought maybe step back and give broad perspective to all of our audience because we've got some, you know, young people that are still in training. We have people recently out of training. We have people like yourself and myself that are, I guess, maybe mid-career working towards senior careers. And then there are people who've been around for quite some time.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
ER visits, readmissions, need for another surgery, stone growth. So again, this kind of gets back to this thing is if we can reduce more stones, will we have a benefit? And sure enough, we did demonstrate this because in the CVEC arm, there were the volume of stones left behind, which was much lower than standard reteroscopy.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Which actually, if I can kind of pontificate a little bit more on the whole stone free rate thing, which I actually recently wrote an editorial or a response to an editorial in the European Urology. Olivier Traxair, who was one of our thought leaders from Europe in ureteroscopy, he is definitely considered a key opinion leader in our space.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
He wrote an article saying, you know, stone free rates are nice. But the problem with the stone-free rate is it's kind of a binary. It's a binary outcome. You're either stone-free or you're not stone-free. So the goal, obviously, is to get everyone stone-free. But what if you're not stone-free? Does it matter if you leave a little bit behind or a lot behind? And he suggested, you know what?
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Instead of looking at the size of a stone, like a 2-millimeter, 3-millimeter, or 4-millimeter, isn't a stone a three-dimensional object? Shouldn't we be looking at volume of stone? And you think about it, it totally makes sense. It's the volume of the stone that probably makes a lot more sense than the two-dimensional. We're kind of dumbing it down when really we should be looking at volume.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So that I think is one of the futures is to look at how much stone are you leaving behind, you know, and not just in two dimensions, but in three dimensions. which is you can see there's emerging research that's demonstrating the importance of volume.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So I think when you're going to see that more and more that people be talking about volume of stone that's been removed and how much volume is left behind and how that translates to all those things that you were talking about post-op problems.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
I think we need you in endourology. It's not too late to convert over. Clearly, with even very little time spent, you already have some good insight into identifying problems that I haven't even thought about.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
If we roll back the clock to the 70s and beyond, it was open surgery was phenomenal. you know, state of the art and really was the standard of care. But then somewhere in the 70s, three major players came in was the introduction of percutaneous stone surgery going through the back.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
There have already been 1,500 cases performed with the new 2.0 in the United States. It's only available in the United States currently. But yeah, community urologists, All types of urologists have used this already, as well as FANS has been used all throughout the United States by all types of urologists. You don't need to have special training for any of this.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
I do think they recommend probably a couple of mentored cases with your territory manager from the company, just making sure you're using the best practices. But no, this does not require specialized training.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Well, I think that number is evolving. What I say today is going to be even greater in a month from now. Like having seen some of the numbers that I've seen of utilization of suction devices and their uptake in the market, it's almost asymptotic. It's really increasing dramatically.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Well, we know that dusting compared to just fragmenting and basketing can be a little bit longer in operative time. So that being said, when the final studies are done, it would not surprise me if there's a slight increase in operative time. But if that time is a couple of minutes in exchange for having to come back to the O.R.,
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
And or readmitting your patient for, you know, obstructing stone or a patient coming to the hospital with an infection and sepsis. Wouldn't it make sense to spend that extra whatever couple of minutes, whether it's single digit minutes or even double digit minutes? I don't think we're talking large amounts of time, but yeah, that's probably the difference is we're talking.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Not like hours or anything. We're just talking minutes of differences, probably, which translate huge for post-op for the patient.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
And then the introduction of shockwave lithotripsy that really trying to change things because now we no longer had to
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
plug and play see what's going to work well for my hands how do i actually make this happen you just simply call these companies up and they would be happy to come to your hospital once this you know the device has been approved by your vac committee i'm sure a trial is set up and then you get to try the different devices to see what which device makes sense to you it's not challenging there's the barriers are not huge they're very low
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Any capital equipment requirements for any of these? Definitely not for fans because that's literally a high-speed access sheet. The CVAC does have a control box, but kind of like any reader scope, digital reader scope, it has a control box. It's pretty tiny. It's about the size of a large laptop maybe. I don't know the answer to that as far as the capital of that.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
cut people or put things in people we just broke them up from the outside using acoustic energy and then came ureteroscopy first there were rigid devices and then we were able to introduce flexible devices and then flexible steerable devices so there's this constant migration and iteration of our technology and i would say for the past since that time there's those are the three players uh that are available to uh patients and depending on your
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
In fact, my sense, I don't want to speak, I'm really not sure.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Yeah, because your scope plugs into the box. It doesn't plug into your striker system or your Olympus system to your monitor. It plugs into the box, then the box plugs into your monitor. So it is an intermediate box or step that you do need. It's my sense that... The cost is simply, I'm almost 100% positive the more I think about it now. I had privy to look at some of the costs and whatnot.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
The hospital is simply paying for the device, the CVAC device, in the case of CVAC, and getting reimbursed, actually, obviously. In fact, there is a transitional pass-through payment code for single-use scopes that can be applied for Medicare patients. So that really lowers the cost to the hospital. And in fact, the CVAC has a unique definition
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
facility reimbursement code that's different than just ureteroscopy. So for in the United States, that has a huge effect on for the hospital and for the providers.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Yeah. Well, the cool thing is there's so many other issues. You've already touched upon some of the things that where we can do it better and better and better. And I'm excited maybe to come back on the show one day and tell you what we're doing and share what other people are doing and how ureteroscopy has suddenly made another huge leap or something else within stone surgery.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So that's the best part of all of this.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Well, I think there's new technology available. There are not huge obstacles to adopting these technologies. And the data suggests that it definitely improves the stone-free rates and lowers the infection rates. So if the learning curve is not huge, which it is not for these devices, then why not adopt them? And I think you'll see for yourself why people are really excited about suction devices.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Design and digital marketing led by Brian Schmitz.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Social media and PR by Chi Ding. Administrative support provided by Judy De La Cruz.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
desire for how much morbidity you're willing to accept as well as you know what type of stone free rates you're trying to achieve you choose one of the three accepting the pros and cons of each of the technologies
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Further, with only 23% of patients coming back for re-resection, it's all the more important to do a complete TURBT right from the start.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So, yeah, great question. I think what we've seen more recently is that ureteroscopy has really become a dominant player.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
It was unclear, I would say, 20 years ago when ureteroscopy was still kind of new and with lasers being used because shockwave was still very commonly used and most people didn't want to subject themselves to a scope procedure when you could just have an acoustic energy being used in the outside. Why would you want to have a scope in a stent place?
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
But what we've seen with the data is that ureteroscopy outcomes appear to be superior to shockwave lithotripsy. And that's somewhat of a broad statement across the board. I'm sure there's some situations where shockwave has its place. But broadly speaking, I think most people would admit that ureteroscopy is a better procedure out there.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
And that speaks to also the studies showing the use of ureteroscopy has grown increasingly. And simultaneously, the use of shockwave lithotripsy lithotripsy has declined. And whereas percutaneous surgery, it makes up more of a minority of the surgeries. It's still there available, but it's still kind of a background player reserved for larger stones.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So that being said, ureteroscopy has become much more common And we thought, hey, we're going to break them up with the homium laser. And there's a new laser out there. And isn't that good enough? And then shouldn't we be done?
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
This week on the Backtable Podcast. Isn't a stone a three-dimensional object? Shouldn't we be looking at volume of stone? You think about it, it totally makes sense. It's the volume of the stone that probably makes a lot more sense than the two-dimensional. It's kind of dumbing it down when really we should be looking at volume. So that I think is one of the futures is to look at
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
But what we found is that even though we break up these stones and hope that some of them will pass and remove some of the bigger pieces with fragments, we found that actually leaving pieces behind has been a problem.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Specifically, the Edge Consortium, which actually I'm a part of, we had a publication demonstrating that there were 20 to 40% complication rates associated with leaving stone fragments behind.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
For example, if you left a fragment behind, you could end up in the ER, you could have sepsis, you might need a stent or even another ureteroscopy, sometimes being hospitalized or just, like I said, emergency visit. So there are definitely complications associated with leaving stones behind. And even though we have lasers and we're breaking them up and dusting them,
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
We're still not at where we want to be for the patients.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
I think, you know, she and many of the thought leaders recognize there's this term out there called clinically insignificant residual fragments. It's an acronym that's used in the stone literature. They would say, well, they're just insignificant residual fragments of three to four millimeters or two millimeters. Well, I think she was astute to realize that No fragment actually is insignificant.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
In fact, the term clinically insignificant residual fragment is actually a misnomer. To that end, one of our journals actually has adopted a new definition of stone-free. Let's say stone-free has three grades. Grade A, the highest grade, is there are no stones, hence the word stone-free. On a CT scale. Yeah. Based off a CT scan.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Grade B would be less than two millimeters and grade C is less than four millimeters. And you may ask, well, shouldn't it be stone free or not stone free? Again, I think this is an evolving thing going on here, but I will say that in that edge paper that I was quoting, we did notice that when we cohorted
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Stones less than four millimeters versus stones greater than four millimeters, we noticed a doubling in complication rates. So the size of the stone, not only the presence of the stone, but how big of a stone you're leaving behind has even a more profound effect on what's going to happen to you as a patient.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
How much stone are you leaving behind? And not just in two dimensions, but in three dimensions. You can see there's emerging research demonstrating the importance of volume. So I think when you're gonna see that more and more, that people will be talking about how much volume is left behind and how that translates to all those things that you were talking about, post-op problems.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Yeah. Or it's the end of the day, right? It's your sixth case. I'm sure those fragments are going to pass. They don't look as big as they seem.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Exactly. I'm sure just like you and probably every urologist out there that works with a trainee particularly the younger trainees, the first time they're doing ureteroscopy, they're like, I'm just curious, sir, why don't we just vacuum these pieces out? And for the past 10 years, every time they would say that, I was thinking, I know, we're working on it.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Because myself and Dr. Hleblian and Brian Eisner, We're all co-inventors of the current CVAC device. We were all at the same time period thinking of the same thing. And about 10 years ago, we all had this idea to create a vacuum or suction device. And that's kind of the genesis of one of the devices that exists out there.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
And CVAC is not the only device, but that is the device that I'm most familiar with as someone that I've used. But I'd like to talk about the other devices as well, because CVAC is not the only one. But that's really how it all started about 10 years ago. And currently that device is now available in the United States. Can I talk more about the history or?
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
yeah i mean from idea to a product that's ostensibly you know approved by the fda to use in humans that's not like something that happens overnight it may take a decade yeah starting in a lab using pig kidneys putting sand in the kidneys and then putting an axis sheath up there and trying to suction it back out with the single with the syringe and different catheters that was all part of the evolution which looking back i still got pictures it was
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
It was fun at that time to think, hey, maybe this will work and see now where we're at. It's really brings me a lot of joy. So what happened is a company was eventually formed and they created the first steerable vacuum aspiration system, which is CVAC 1.0. There's now a 2.0 out there. The CVAC 1.0 was good, but it was done under fluoroscopy. There was no camera associated with it.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
And about 2,000 cases were performed throughout the United States. There was in fact even a multi-institutional randomized controlled trial called the ASPIRE trial, which was performed to demonstrate its efficacy over just ureteroscopy and basketing, which in fact it did.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
But I think a lot of the critics were, you know, gave the company feedback as to, look, you know, this is great, but I can't really see what I'm doing here. And wouldn't it be nice if we could see something? So their engineers went back to the drawing board and they came out with 2.0, which is an all-in-one system that actually replaces the ureter scope because it has...
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
A camera has constant irrigation, constant aspiration, the ability to break up stones with a laser, and even collect. It has a little canister attached to the scope. So as you're breaking up the stones and aspirating, you're looking at the canister just literally filling up with stones. So that's the current generation that we're using right now for CVEC, and that's where we're at with that.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
Well, Brian Eisner and I, we would go to the lab at University of California, Irvine with the team and we used a live porcine models. And so we would perform the ureteroscopy, use the CVAC, and then pass a scope back up there to see what would happen with the hopes that, please, please, please don't let there be too much mucosal injury. And fortunately, we never really saw a lot of mucosal injury.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
And even more fortunately, it didn't translate into clinical trauma. So again, in the RCT and in our use, anecdotally, it really is a safe device, but it just was not adequate enough because we couldn't see. We're using fluoroscopy. Even though it was steerable, we couldn't see it visually.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
That remains a problem, actually, which is a whole other conversation with machine learning that I would love to talk to you about some of our ideas and some of the things that we're doing. But I think machine learning will solve some of those problems because we have not solved that problem. So you're on to the next set of problems.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
So you're obviously a student enough to realize, even though you're an oncologist, you realize we haven't solved all the problems. There's so many more problems that we have to do, which... Which makes it fun to be in research. So you're right. Size is a problem. Obstruction is a problem. We had to figure that out. We had to make sure it was safe. Above all else, it had to be safe.
BackTable Urology
Ep. 197 Suction Devices in Urology: Improving Stone Removal with Dr. Roger Sur
And then we had to overcome the obstacles that would occur like obstruction.