Debators: Bodo Knudsen and Ben Chew

Moderator: Mitchell Humphreys


Mitchell Humphreys, MD

Mitchell Humphreys, MD is the Department Chair and Professor in the Department of Urology at Mayo Clinic Arizona. In addition, he serves as the Dean of the Mayo Clinic School of Continuous Professional Development as well as the Endourology Fellowship director.

Dr. Humphreys completed Medical School at the University of Missouri, Residency at Mayo Clinic in Rochester, and an Endourology Fellowship at Indiana University. His clinical focus is on surgical and metabolic stone disease, BPH (with a special focus on HoLEP), and minimally invasive GU oncology.

Dr. Humphreys has funded research initiatives in stone disease, BPH and adaptive patient education technology. He is involved in several multi-institutional groups and is one of the founding members of the EDGE (Endourologic Disease Group for Excellence) research consortium.

He has published over 110 peer-reviewed manuscripts and multiple book chapters. Additionally, he is on the Board of Directors of Global Surgical and Destination (GSD) Healthcare, LLC a non-profit organization promoting basic healthcare initiatives in impoverished areas around the globe. He also serves as a Board of Trustee to Columbia College which attends to the higher educational needs of a student population of over 30,000 learners.

Bodo E. Knudsen, MD, FRCSC – Brief Biosketch

Bodo Knudsen, MD, FRCSC is the Director of the Comprehensive Kidney Stone Program at the Ohio State University Wexner Center and holds the rank of Associate Professor with Tenure. He holds the Henry A. Wise II Endowed Chair in Urology and is currently the Vice Chair of Clinical Affairs within the Department of Urology. Dr. Knudsen completed his medical school at the University of Manitoba in 1997 and his residency in 2002. He then completed fellowship in Endourology under the supervision Drs. John Denstedt and Stephen Pautler at the University of Western Ontario in London, Ontario, Canada. Dr. Knudsen joined the Ohio State University in 2005 and has been on faculty since then. His clinical practice is primarily focused on stone disease. Dr. Knudsen is a member of the R.O.C.K. Society and the EDGE Research Consortium. Dr. Knudsen has published extensively in the field of Endourology but also strives to achieve appropriate work/life balance and has been proactive in physicians achieving overall well-being.

Ben H. Chew, MD, MSc, FRCSC

Dr. Chew is a urologist and the Director of Clinical Research at the Stone Centre at Vancouver General Hospital and an Associate Professor of Urology at the University of British Columbia in Vancouver, Canada. He is also the Chair of Research for the Endourological Society (www.endourology.org ). His main interests lie in the treatment and research of the pathophysiology of kidney stone disease. His research focus includes metabolic stone disease as well as biomaterials used in the urinary tract for ureteral stents. He has worked on various stent designs, stent coatings and drug-eluting ureteral stents to try and improve the quality of life for patients with kidney stone disease. He continues work on a degradable ureteral stent and has completed the first-in-human trials. Current studies include attempting to understand second messenger systems that are activated within the kidney and ureter once a ureteral stent has been placed. These could be exploited as future therapeutic targets for new drug eluting ureteral stents or designs to reduce symptoms. He is a consultant to a robotics company in the race to develop the first robotic assisted ureteroscopy.

He has authored over 95 peer-reviewed manuscripts and book chapters. He is a member of the Endourologic Disease Group for Excellence (EDGE) research consortium (www.endoedge.net) and the Wisconsin Quality of Life (WISQoL) research consortium.


 

Webinar Transcript

Dr. Ben Chew:

Good morning. Good afternoon everyone. Thank you very much for joining us. Welcome to The Endo Society Master Class in Endourology and Robotics. I'm Ben Chew from the University of British Columbia in Vancouver. On behalf of Dr. Adrian Joyce and Dr. Brian Matlaga, who are the chairs of education for the Endo Society, welcome.

Dr. Ben Chew:

Today, our esteemed panel is Dr. Mitch Humphreys from Mayo Clinic, Arizona. He is going to moderate our session, and Dr. Dr. Bodo Knudsen from the Ohio State University.

Dr. Ben Chew:

First of all, I'd like to thank Cook Medical for their grant in support of this educational activity. Without them and other companies, other activities like this would not be possible, so thank you very much.

Dr. Ben Chew:

The other thing I want to mention is that afterwards, you will get an email from Michele Paoli, who will tell you how to get your CME credits. And afterwards, when you exit this webinar, you'll immediately go to an online feedback form, which is important in order to get your CME credits.

Dr. Ben Chew:

Today's format is going to be a little bit different. We are not going to debate each other. This is a bit of an interesting exercise. What we're going to do is we are going to watch the balloon debate from the WCE, which was in Abu Dhabi last year, and watch how they debated and discussed a 15 mm lower pole and how it should be treated, and then we're going to talk about each of their debates and each of their arguments and sort of what we would do as well, too. So, in case you did miss that debate, or if you want to get another point of view, it's basically a commentary on that.

Dr. Ben Chew:

So, I'm going to hand it over to Dr. Mitch Humphreys, who is going to moderate the session, and also give his comments as well, too.

Dr. Mitch Humphreys:

First of all, I want to say welcome to the panelists, welcome to everybody that's tuned in today. I think this will kind of be an interesting thing as we go through this and take about the debaters and some of the literature around it, some of these selections, and hopefully come up with some clinical pearls to bring value when considering these patients with that 15 mm lower pole stone. I think we've got a great panel with Dr. Chew and Dr. Knudsen today. So, as we get this rolling ...

Video moderator:

I'm really happy to be here to moderate this very interesting debate on this topic, 15 mm lower pole stone. So, this is a real case. This is a patient that came to my attention two weeks ago. So I'm a little bit in trouble in deciding which is the best treatment modality. She is a 53-year-old lady, not very big as usually [inaudible 00:02:40], and she is a colleague. She is diabetic on oral therapy and she had prior stenting for a 1.5 stone at the UPJ because of severe fever and positive urine cultures. So she was treated for two weeks with meropenem. Actually, she's doing well. The stone has been pushed back in the lower anterior calyx. Hounsfield density is less than 1000. Now, urine cultures are negative and stent is in place since one month. The patient is really trusting me. She said to me, "Doctor, do whatever you think is the best way to render me stone free."

Video moderator:

This is the CT scan. As you can see on the coronal image, there is a 1.5 lower pole stone. Density is, as I told you, to 900 and some mild colonic interposition. As you can see in the axial image, there is a little bit dysmorphic kidney with this stone in lower, but very anterior calyx, and again a little bit of colonic interposition. Stent is in place, but a little bit downward displaced as you can see. According to the UROCT scan performed before stent placement, as you can see, the anatomical features of the kidney are quite favorable. Infundibulopelvic angle is wide, 56 degrees. Infundibulum width is 9 mm and infundibulum length is 2.5 cm. Skin-to-stone distance is 9 cm.

Video moderator:

But today I'm lucky enough that I have so many prominent endourologists. We will have Dr. Wu from China that will do super, super mini. Then we'll have Khurshid Ghani supporting flexible ureteroscopy, Dr. El-Nahas from Kuwait supporting ESWL, Dr. Khadgi from Nepal mini perc and Dr. Agrawal for ultra mini perc and finally Tim Averch for standard perc. So these are the instructions. Two minutes talk for every speak, then we vote. In the first round, two will be out, then one ...

Dr. Wenqi Wu:

Good morning, everyone.

Dr. Mitch Humphreys:

I just want to pause here before we get into the debate with our panelists here. Given the clinical information that you have, 53-year-old female, 30 BMI, obviously a physician, with diabetes. We saw the scan. Before we start, just given that clinical picture, in today's practice, before we get into the debate, what would you guys do in your current treatment? Let's start with you, Ben. What would your treatment of choice be?

Dr. Ben Chew:

I think this is not a really straightforward case. I think it's a bit different, too. Why is this kidney so dysmorphic? It's not just a regularly kind of positioned kidney. So I think that's very interesting. The stone has moved from the UPJ into the lower pole. She does have a history of sepsis, as well, too. So certainly I think you want to clear as much stone as you can. The problem is that I think it's really quite anterior where the stone is, so that's really kind of negating a little bit of the PCNL access for me. That's a little bit of something. So, I would have a talk with her. Really I would sort of be talking to her about a few modalities that I would offer, which would be standard PCNL, flexible ureteroscopy or shock wave, and the pros and cons of each of those. I'll let Bodo answer.

Dr. Mitch Humphreys:

Before we go to Bodo, Ben I'm going to put you on the spot, and this is your patient, you don't get to talk to her about options. What would you do? If you had the ideal situation and said, "This is your situation, this would be my number one recommendation." If you can pick one treatment [crosstalk 00:06:34].

Dr. Ben Chew:

You want my final answer right now at the very beginning of this Webinar?

Dr. Mitch Humphreys:

I want it at the very beginning so we know how to frame it for the rest of the day.

Dr. Ben Chew:

I think given all that, I think that PCNL is probably not the best option, at least in my hands. I would probably go with flexible URS if you wanted to have one procedure. If they're a bit chicken, I would say you could try shockwave. It's a little bit big. Density is not bad. But I would say that flexible ureteroscopy.

Dr. Mitch Humphreys:

Bodo, what's your take?

Dr. Bodo Knudsen:

Yeah, I think for me, I would approach this with a supine mini PCNL with the option of ECIRS. We'll be able to get a good calyx to come in and if you don't like where the stone is, we already know the stone can be moved. It moved from the UPJ to the lower pole of the stent, so it should be easy to relocate the stone if you need to, and we're going to have a better chance of getting out all those pieces with the mini PCNL.

Dr. Mitch Humphreys:

So, hopefully later we'll get into the choice between supine and prone later on in the debate as that goes on, but I appreciate that. Let's first hear about our super mini PCNL and then we'll ask some more questions.

Dr. Wenqi Wu:

For this case, my choice is SMP.

Video moderator:

Go ahead. Go ahead.

Dr. Wenqi Wu:

Okay. Just note that for this case, compared with shockwave RIRS, PCNL can provide a high stone-free rate for this case. You may recall that patient is [inaudible 00:08:09] ultrasound combined C-arm we can get very accurate puncture, either with prone or supine position. Also, if needed, we can use RS. When we use SMP, this means 12 or 14 tracts, so that means less bleeding, less transfusion, less hospital stay and less pain. You'll get less complication, especially with two-layered metal suction sheath. We can do the procedure very quickly and also we separate the inflow and outflow so you can use a big laser fiber to break the stone faster. Most importantly, we can remove the stone by suction. So compared with flushing the stone out, we'd be more efficient.

Dr. Wenqi Wu:

We shouldn't forget that the patient had UTI and also diabetes. With negative suction, we can keep lower intrarenal pressure and we can keep the patient safer, so we can even do day-surgery for this patient. So, we'd say SMP is much safer and effective.

Dr. Wenqi Wu:

But the lady wants to know what [inaudible 00:09:21] SMP compared with other instruments. I don't know whether you guys want to know. If you guys also want to know, please elect me for next round. Thank you.

Dr. Khurshid Ghani:

Thank you.

Dr. Mitch Humphreys:

Before we go onto Dr. Khurshid Ghani and the flexible ureteroscope, Bodo, since you were talking about mini PCNL, it brings up a great point. When we talk about super mini PCNL, ultra mini PCNL and some of these terms that are thrown around, what is your thought in terms of positioning for prone versus supine?

Dr. Bodo Knudsen:

My own experience has been we really took to doing a lot more minis as we switched to supine from prone as kind of our default positioning. I think having that tract that's in a more sort of dependent position to allow those fragments to flush out, gravity works with you on a supine. And then we started to get some of the other benefits of supine, too, being in an ergonomic position as a surgeon, it's very quick to position people, anesthesia likes it, so there's the other advantages. But I do think the pieces come out easier when you do it supine.

Dr. Mitch Humphreys:

Any tips? Because what I've noticed in supine is the lower pole has a lot more mobility in the supine position than when in the prone position. Any thoughts or tricks for people?

Dr. Bodo Knudsen:

You've just got to spend the time to get your wire down. Once you get your wire down, you're fine. Usually getting the actual stick, thinner women are the ones that have the most mobile lower pole. But once you get in there, you've just got to spend the time. Whether it's using your technique with the glide and doing the loop-the-loop in the upper pole to get the wire down or using your angled catheters, overhead catheters, you've got to just spend the time to get the wire down. If you ultimately can't and it's so mobile that you can't dilate, then you can go up with the scope and grab the wire and take it down. But you've got to spend that time on those mobile pieces.

Dr. Mitch Humphreys:

Ben, do you have any thoughts between what you prefer for supine versus prone?

Dr. Ben Chew:

I've started doing a bit more supine. I know it's done a lot of other places. The one thing I do like ... I've actually been doing more endoscopic combined or ECIRS approach actually, and I think it's been helpful in a lot of places, particularly if there's a big staghorn and I can't get the wire by the stone, or a big obstructing stone. You can laser a lot of that with your ureteroscope first and it's just nicer to do that in the supine position. It's a little bit trickier. We're actually more used to doing prone here, so it's funny, the nursing staff and the OR staff are actually more used to doing prone than we are for the supine. But we're just getting those fine adjustments, because you can make a lot of little things to adjust for it. But there's no question that anesthesia really prefers it. I'd say the vast majority of mine are still prone.

Dr. Mitch Humphreys:

Great. All right, let's get back and hear about flexible ureteroscopy.

Dr. Khurshid Ghani:

So, we're going to discuss the surgical options, ureteroscopy, shockwave lithotripsy, PCNL and then we've got these surgeries. Does anyone actually know what we're talking about here. Does anyone actually know what an ultra or a mini or a super mini is. Are we serious? But this is not a game. This is serious. Every patient has to be treated with respect like you would your own mother. So let us meet this patient. We already heard from Dr. [inaudible 00:12:55], a 53-year-old female. Remember, she's a gynecologist, a 1.5 cm stone in the lower pole, Hounsfield unit 900. What is the best surgical option? Look at the AUA. The AUA says PCNL is not the recommended standard for stones less than 2 cm. If it's in the lower pole, shockwave lithotripsy should not be offered for stones more than 1 cm.

Dr. Khurshid Ghani:

EAU says the same thing. For lower pole stones more than 1 cm, don't do shockwave lithotripsy. Where's Dr. El-Nahas? You'll hear him speak soon to tell us about the wonders of shockwave lithotripsy. Look at this series that he published. 9.2% hospital admission rate after shockwave lithotripsy, and what was the major risk factor if you had an existing ureteral stent? And then here is the level one evidence, randomized control trial of ultra mini versus shockwave versus ureteroscopy. In this series, ultra mini had greater hospitalization and more complications and ureteroscopy was the best treatment option for 1 to 2 cm lower pole stone.

Dr. Khurshid Ghani:

Let's ask us in the room, in this survey again from Dr. El-Nahas, when urologists were surveyed, for the 1 to 2 cm stone, ureteroscopy was the number one choice. Overtook PCNL. So on this basis, I would submit to you that this is the primary treatment modality and we should follow it. Thank you.

Dr. El-Nahas:

Yes, the EAU Guidelines, if there is unfavorable factors for ESWL, if these factors are not present, SWL or endourology is the optimum treatment for 1 to 2 cm lower pole stone. This patient has specific factors favoring ESWL. The stone density is less than 1000 Hounsfield units. The skin-to-stone distance is less than 10 mm. The body max index is 30. There is favorable lower calyceal anatomic: Infundibular length 2.5 cm, infundibular width 9 mm and infundibulopelvic angle 70 degrees.

Dr. El-Nahas:

For the patient, it's very important the choice of treatment because it affects the quality of life and when this paper compared to the quality of life for all treatment options, they concluded that post lithotripsy health related quality of life was superior for SWL compared to ureteroscopy on the discharge date, despite the lower stone-free rate of SWL.

Dr. El-Nahas:

If we compare the advantages and disadvantages of endourology against SWL, we'll find the stone-free rate is good in endourology, retreatment rate is better for endourology. On the other side, the complication rate is lower in SWL, hospital admission, anesthesia and the patient satisfaction. So the results are four against two.

Friends clip:

Mr. Tribiani, I'm afraid you've got kidney stones.

Dr. Mitch Humphreys:

I'm going to pause on the sound from the Friends video, just to get into a little bit of a contemporary discussion here. So, it's interesting. We've heard now about ureteroscopy and shock wave for a 15 mm lower pole stone. As everybody knows, we have two historical landmark papers in endourology. Lower pole one that compared shockwave to PCNL for lower pole stones, and then lower pole two that compared shockwave to ureteroscopy for lower pole stones. Just borrowing from that data, that stone free rate 35% versus 95% for shockwave versus PCNL, and then again, surprisingly, in lower pole two, again the stone free rate with shockwave was 35% and for ureteroscopy was 50%.

Dr. Mitch Humphreys:

My question to you, considering lower pole one and lower pole two, I think those studies were from 2001 and 2005, very well done studies, but are they contemporary for 2020 and do they influence what we do today considering the technological advances in platforms, laser, mini technology, all of those things. I'd love to hear your thoughts on that. Ben?

Dr. Ben Chew:

I think that's a good point, Mitch. When we get through all these questions, I forgot to ask you which one you would do for this patient. You got me and Bodo, but we've got to get you on that one. I was looking at this and Dr. El-Nahas' presentation is really good. I think as long as we talk to the patient and tell them about the limitations of this that, this patient is only, I can't remember, 30-something, but if she were elderly certainly I think it's worth it to go ahead and try shockwave first and I tell patients that. They're willing to undergo even two or three shockwave lithotripsy treatments rather than one ureteroscopy. Anyone who's ever had a ureteroscopy says, "Oh, I really don't want that stent." That's been a big thing that people have said to me. We do a lot of shockwave here. We're not always successful. I certainly would say that this is definitely going to be a lower stone-free rate, lower success rate, but I wouldn't shy away from it, as long as a patient understands that they're going to be better off with a ureteroscopy or one of these other percutaneous procedures.

Dr. Ben Chew:

The other thing that we do that's different from this stone is we know this stone is mobile because it's come from the UPJ and has moved back to the lower pole. So this is not, I think, one of those lower pole stones where we don't know it's going to be stuck, we don't know what the infundibular angle is, we don't know how wide the infundibulum is, so I think this is a bit more advantageous shockwave.

Dr. Ben Chew:

There was a good study done by John Honey and Ken Pace in Toronto, where they did mechanical percussion and inversion after shockwave for lower pole stones. What they found was it was a lot more effective. So I've been getting patients to do that. It's a homemade version of it. Honey and Pace's version was they put them on one of those spine boards, took them upside down, used sort of the Acme boxing gloves for patients with cystic fibrosis to kind of really pummel their back with intravenous Lasix after the operation. And it worked better, but I think patients really didn't like being hung upside down. So we'd get them to sort of crawl on their bed, drink a couple of glasses of water beforehand, put their forearm on the ground so that their head is lower than their hips and then get either their spouse or themselves to hit themselves in the back, and that's actually been shown to work as well, too. I really Dr. El-Nahas' presentation on that.

Dr. Mitch Humphreys:

Bodo, your thoughts?

Dr. Bodo Knudsen:

Clearly, technology has changed, probably most so on the ureteroscopy side. I think the scopes that were used in 2005 compared to now are quite different and the visualization is better now. So I would say for ureteroscopy things have changed somewhat. And the thulium fiber laser is probably going to change things again significantly. And then for PCNL, mini was around but not as evolved and developed as it is now in some of the other options like SMP and UMP. So I think the morbidity of a perc has gone down since 2001 when that study was done, and I think you can get comparable stone-free rates with a mini versus a standard. So I think that's important to consider and I think further adds to the argument that a mini PCNL would be ideal for this stone.

Dr. Mitch Humphreys:

I will say I think those are great points. The one thing that's interesting though is, if you think back to 2001, the lithotripter that had the lion's share of the market at the time was the HM3. We know from data that that was actually better at pulverizing stones, because of the F2. So, it really does bring up some interesting points. Okay, we want to make sure we get everybody in, so now we'll go back to Dr. Agrawal to hear about ultra mini PCNL.

Dr. Sanjay Khadgi:

Undoubtedly and boldly, mini PCNL is the best modality for a stone of 1.5 cm. I must wake up my friends before I speak on what really mini PCNL is. These are the advantages of mini PCNL technique. If you use the other modalities, you have to all of these instruments and accessories, whereas if you perform by mini PCNL technique, you just need one table with 12-French miniature nephroscope and simple pneumatic LithoClast.

Dr. Sanjay Khadgi:

We perform mini PCNL under spinal anesthesia in adult patients, in prone position, and we make our access with our own. It's bloodless. We go through the fornix of the kidney. We start the dilatation with the fascial dilators, first with the 10 or 12-French, then with the 18-French. This dilatation is gently done with a clockwise and anticlockwise direction. This hardly takes two minutes in our setup. Once the dilatation is done and sheath is placed in the system, then we inspect with the miniature nephroscope. We use the pneumatic LithoClast, which costs hardly 2000 US dollars, whereas a laser costs more than 100,000 US dollars. These stone evacuations are done just by irrigation. This procedure takes hardly 10 to 12 minutes in our setup.

Dr. Sanjay Khadgi:

These are the results when you perform mini PCNL technique. The success rate is 95 to 100%. Again, mini is not only for the small stones, even for the staghorn and other stones we perform mini PCNL. This is one example [crosstalk 00:22:52].

Video moderator:

Time please.

Dr. Sanjay Khadgi:

... staghorn stone with complete removal next day. These are the stones. So, thanks. There is no better way to remove stones from the kidney other than mini PCNL technique.

Video moderator:

Okay, thank you very much.

Dr. Mitch Humphreys:

What I was going to say is when I watch his technique, his technique more similarly mimics what we see in interventional radiology, where they perc into the kidney wherever they can, do the contrast and then do their perc. Because if you saw, his needle track was different from where he actually dilated from the stone. Do you have thoughts about that? We usually go up for retrograde access, or now people are going to ultrasound and going single puncture. What are your thoughts on that?

Dr. Ben Chew:

If I can go first, Bodo, if you don't mind. I actually did this just two days ago, Mitch. We had a very obstructing proximal ureteric stone that was about 2 cm. I put a retrograde up and I couldn't get any contrast by it, or just a little bit of contrast by it. So I actually took a 22 gauge spinal needle and just put it right into the pelvis, aspirated urine back and then injected contrast so that I could do the puncture. That's only because I can't do ultrasound puncture and I think that's becoming more commonplace and I think I'll have to learn out. Because the people who do ultrasound make it look so easy and Tom Chi and Jianxing Li are two of the pioneers in this, and I like Tom's comments that there's no having to figure out which one's posterior when the one closer to the skin is the posterior one, posterior calyx, so that's been a lot easier.

Dr. Ben Chew:

But I think it's something you should be prepared to do in case you can't get a retrograde up. Occasionally people can't, if they have too much trabeculation in their bladder from BPH, sometimes you can't find the ureteral orifice. I've had that one time and I just had to perc right onto the stone, but not something I would necessarily do all the time because I think it might increase your risk of bleeding. But if it's a very small needle, like a 22 gauge, I think that would be fine. That's something we should be prepared to do.

Dr. Mitch Humphreys:

Great trick. Bodo?

Dr. Bodo Knudsen:

I think the key here is ultrasound. We still put a retrograde up on every case so that we have access from below, and we actually run some fluid through the catheter during the mini percs to get a little bit more flow up into the kidney, but if you have one like Ben had that's completely obstructed, those are usually the easiest ones by ultrasound because the kidney is big and dilated. Once you start getting a few ultrasound accesses under your belt, those are the super easy ones where you've got a huge target.

Dr. Mitch Humphreys:

Perfect. All right. We're going to play through some of these to make sure we get through all of them here.

Dr. Agrawal:

If you look at this case carefully, there are two very important things which you need to focus on. One is this patient presented with fever and we need to do something which will not make this worse. The other thing which we emphasize on, if the patient trusts him to give complete stone-free status at the end of the procedure, and this should guide us to decide what is the best procedure. You can see that the stent has not reached the kidney and there is a narrowing in the infundibulum. Both these things will probably interfere with flexible ureteroscopy. On the other hand, a percutaneous approach is straightforward and gives a decent window, not withstanding the colonic position which is far anterior, and entering through the posterior calyx and going into the anterior calyx here would be very simple percutaneously. Choosing percutaneous approach is also according to the guidelines for a 15 mm lower pole stone.

Dr. Agrawal:

To select the least invasive percutaneous approach makes sense and when you go to the smallest percutaneous approach, when you use ultra mini PCNL, you reduce the morbidity significantly by reducing the tract size. As you can see from this recently published study, reducing the tract size reduces the complication rate significantly without compromising the safety of the procedure, and at the same time gives you equivalent stone-free rates. At the same time, if you compare with flexible ureteroscopy, you get far better stone-free rates. Thank you.

Video moderator:

Thank you very much. Last ...

Dr. Tim Averch:

I have no disclosures except I want to clear the kidney stone successfully, safely and completely in this patient and there really is only way to do that, and that means you have to pick me because bigger is better. The goals of a stone procedure and a PCNL is stone clearance, and this patient has an infection stone. It may not be struvite, but still infection-related. So we want to use a couple of American expressions here, bring the big guns and wear your big boy pants, because it's time to clear the stones. As it was pointed out earlier, who wants mini anything? Remember, just because it's the original doesn't mean we should discard it or put it to the side. I was inspired at the Presidential Palace earlier this week and saw Al Zahrawi's work in foundations for lithotripsy. Still, you can see some of those tools are in use today, so we still can't discard things we used to do for a while now.

Dr. Tim Averch:

The TRUST group has said that completely stone-free status seems to be the utmost importance since even residual fragments smaller than 4 mm could be responsible for symptoms in the future. Standard PCNL in the literature, I can't really show you much today, because most of the literature today is about the new "cool" technique, so there's a lot of bias in those studies. But they're all compared to the gold standard, the standard PCNL.

Dr. Tim Averch:

PCNL true stone-free rates, you can look at anywhere in the literature that despite lower risk in many of these other procedures is stone-free rate is still superior in a PCNL. Bleeding, well for the most part we can use a high pressure balloon, 30 atmospheres. We looked at that in our own series and saw a minimal bleeding risk at just over 1%, so we can avoid that complication all together.

Dr. Tim Averch:

Complete removal of the stones. We have instruments, graspers, tipless baskets, the flexible nephroscope, all things that we can do to remove that stone burden completely.

Dr. Tim Averch:

Last, I have to just conclude with just, go big or go home. Thank you.

Video moderator:

So, Dr. Khadgi and Dr. ...

Dr. Mitch Humphreys:

Okay, so before we get into the voting results, what I would ask the panelists, if you looked back on those CTs, where they were showing the access window for this kidney was, I think it was above the 11th rib, so it was supracostal access for this lower pole stone. What do you think about PCNL access to this particularly stone in this particular patient? What are your thoughts on supracostal or subcostal?

Dr. Bodo Knudsen:

I suspect I would still end up coming subcostal, because typically my tract into the lower pole is going to come at an angle, especially with the use of ultrasound we have a little bit more ability to angle things. So it's hard to know sometimes until you actually have the patient on the table and you see where the kidney is moving and breathing, but my guess is we would have still been subcostal on this patient.

Dr. Mitch Humphreys:

Ben?

Dr. Ben Chew:

I agree. I have nothing to add to that. I would do the same thing as Bodo, except for the ultrasound portion. But I do tend to sort of come in lower pole. And rather than try to get into a perfect access that I would be able to go into the upper pole, if the stone is really just in the lower pole, I'm a little bit less fussed about trying to get into the rest of the kidney now, particularly if there's some kind of dysmorphism or if the patient is really obese. I will tend to sort of even come in at a big of an angle that won't be favorable for me to get into the upper pole, because I just want to get into the lower pole and get that stone out.

Dr. Mitch Humphreys:

I'll be honest. Sometimes I've had some patient with large BMI, when you start to talk 40 BMI and I do them prone, even with that lower pole stone, sometimes I'll perc into that upper pole and I still have enough access to get into that lower pole, even with flexible nephroscopy or something like that, when they may have an odd lie of that kidney. So just for the audience, just so you know, the two modalities that were kind of voted off was shockwave and mini PCNL. Do our panelists agree with them being voted off for treatment for this patient?

Dr. Ben Chew:

That's funny because Bodo picked mini PCNL. Obviously we're kind of biased about what we would do, too. I think shockwave definitely loses in these kinds of debates, and I think this is a bit of an academic debate for me for sure, but there's no question I have done shockwave for these exact same kind of cases. That Hamamoto paper for the SMART study group in Japan is something that we're trying to replicate now on a bigger scale in the Endo Society under the research arm, because what it shows is that sure you do ureteroscopy and shockwave. You would initially think that your quality of life would certainly be worse with ureteroscopy over the first couple of days because of the stent, because of the surgery. But six months later, the quality of life is still better for shockwave, even after your stent is removed and everything else, and even though your stone free rate is lower. Why is that? There must be something else. So I think that we can't underestimate that, that we as surgeons always think that stone-free must be the best thing, but when we ask patients what it is, I don't think it's necessarily the same things that they want.

Dr. Mitch Humphreys:

All right, so Bodo, I'm going to assume you are going to stick with your PCNL, but [crosstalk 00:32:52].

Video moderator:

... El-Nahas are out of the debate, okay? Thank you very much anyway for your support.

Dr. Wenqi Wu:

Okay, first I have to say, thank you everybody. You let me go back. Okay, now let me talk to you about my answer. First I say why [inaudible 00:33:12] shockwave. [inaudible 00:33:16] the patient [inaudible 00:33:15] so shockwave for this patient is not good. I also know that patient [inaudible 00:33:24] collecting system and a long infundibulum, so even if you break stone with shockwave, it's not easy to pass out. So also you remember the patient wants to be stone-free. Okay, the RIRS is out, so we continue, if we choose PCNL, why we didn't choose standard PCNL. If you choose standard, that means that you get more bleeding, more transfusions and longer hospital stay. That's when you get much more complications. Also, I think that the patient would ask you, "I have only 1.5 cm stone, Doctor, you choose so big tract for me. I'm worried about the trauma." So, that's out, so let's go to UMP. I think UMP has the same size compared with SMP, but we also know that it uses more sheaths to flush the stone out. That means the stone and irrigation will fight in the sheath. That makes the stone come out slower. Also, they can only use small fiber that's low energy that also cannot break the stone so fast.

Dr. Wenqi Wu:

So compared with other methods, I think still SMP is the best. Thank you.

Dr. Khurshid Ghani:

"In every patient I see my mother, and in every relative I see myself." Wise words from Dr. Mahesh Desai. So let us meet this real patient. This is not a game. We're talking about a real patient that Guido has to deal with. Number one, she's a gynecologist. Number two, 1.5 cm stone in the lower pole, Hounsfield unit 900 and it's a dysmorphic kidney. The reason the guidelines state that if you're less than 2 cm you should have ureteroscopy. It's all about volume. Look at the difference between this stone and a 2.1 cm stone. Look, it's an anterior calyx. And look at that kidney, do you really want to puncture into that kidney. And then you'll say that the meta analysis shows that there's a better stone-free rate with ureteroscopy but it's clear, PCNL has more complications. Even in this paper from European Urology, it says, "Given the added morbidity, RIRS should be considered standard therapy for stones less than 2 cm."

Dr. Khurshid Ghani:

Remember, the patient is a gynecologist and bleeding can lead to nephrology. This is Guido's boss. "Hey, Guido, how did that PCNL go with Dr. Gyn?" "Bad, my friend. Kidney bled and we had to do a nephrectomy. She had a dysmorphic kidney." This is his boss thinking, hmm, maybe I need to get a new endourologist. "But the patient wanted to be stone-free." Well, if you look at the data, it's all based on old series of old lasers and old techniques, and I think our outcomes are so much better. If you look at Dr. Averch, who's in the audience here, "God wants us to do a ureteroscopy because this patient is pre-stented. Pre-stenting means this is the way to go."

Dr. Khurshid Ghani:

So this is what I would tell the patient: I'm going to mitigate your risk of sepsis. I'm going to use a large access sheath. I'm going to dust and extract your stone, place a stent and follow you up and these are the outcomes I expect, just as in the similar patient of mine. Thank you very much.

Dr. Agrawal:

Ultra mini PCNL ...

Dr. Mitch Humphreys:

Sorry. I want to pause here for a second, just because he brings up some good points about pre-stenting. My question for you guys is, how often do you pre-stent? And during ureteroscopy, how often do you have primary failure, where you cannot get the ureteroscope up? I'll start with you, Bodo.

Dr. Bodo Knudsen:

We don't routinely pre-stent. Often the ones that I get that are pre-stented have been stented elsewhere and then sent in. There's no question it helps. It dilates the ureter, makes it easier to get up. And then I think it increases the chance of not having to leave a stent after the procedure. In terms of primary failure, I'd stay it's still around 10%. It depends on your ureteroscopes. But, we certainly get patients with tight upper ureters and in those ones then we'll put a stent in and we'll come back another day.

Dr. Ben Chew:

I think it's something you should tell everyone. I think they published 9 to 11%, I think. Around 2%, I think, is really good. Sure, we can dilate with a ureteral access sheath, but then you see a split in there. I know the studies show that there's not a higher rate of stricture, but still it's just not nice having to have that stent in there for a longer time and having to worry about this patient. For me, I give them extra radiation because then I need to ensure that they do not get a stricture. So they get a lot more tests afterwards. But I would say it's around that number, and it's really important to tell a patient, "Look you may just wake up with a stent because that's the safest thing to do," and I think that's an important thing.

Dr. Mitch Humphreys:

Perfect. All right. Thank you.

Dr. Agrawal:

... was first reported by Janak Desai and he showed excellent results with hospital stay of just over a day and clearance rates close to 90% with ultra mini PCNL. We published our results soon thereafter with over 100 patients with complete stone clearance in close to 99% of patients, with a hospital stay of less than a day, with minimum morbidity matching that of flexible ureteroscopy. Now, this is a one-step procedure with hardly any bleeding, and morbidity as low as that of flexible ureteroscopy with complete clearance on operation table. All of the fragments are removed and the patient is left with just a 3 to 4 mm incision which heals by itself and the patient can go home within 24 hours or less.

Dr. Agrawal:

There are multiple studies available, and these are recent studies, not old studies, which have shown that the stone-free rates are best in mini PCNL and ultra mini PCNL as compared to flexible ureteroscopy, and this is a very recent study published only this year. Of course, there is no doubt that, given the fact that there are so few disposables used, the cost of ultra mini PCNL is significantly less than flexible ureteroscopy. Thus, it's applicability all over the world to all kinds of populations is much better. Thank you.

Dr. Tim Averch:

All right, well thank you for the vote of confidence. We're going through round two here. Remember, we want to leave no stone behind. So even in all this literature you've seen presented today, even in expert hands, all of these techniques can leave stone behind except PCNL. Goal should be complete evacuation of the stone burden. Because, why? Recurrence rates. We know those are going to be high if you leave stones behind.

Dr. Tim Averch:

I think we can eliminate shockwave lithotripsy, which you already have unfavorable anatomy and the size of this stone. Ureteroscopy, clearly the literature says we're probably still going to leave some stuff behind. I agree, maybe we don't know everything with the current technology, but dusting, there's plenty of studies out there that says this is not the way to go.

Dr. Tim Averch:

If we look at even in the expert hands in our lower pole stone study, shockwave ureteroscopy, you do a CT scan for follow-up, you still have at best 50% clearance. And those patients do have complications.

Dr. Tim Averch:

Super mini PCNL beats ureteroscopy, so already my opponents are defeating themselves here. Three month stone-free rates are significantly different and there's significantly less ancillary procedures, as well.

Dr. Tim Averch:

Does small even matter? There are many animal studies out there that the size of the hole we place in the kidney really doesn't make a difference. A recent study in 2010 showed that in a mini perc there was no difference in any of the inflammatory factors we see in the kidney from the size of the hole in the kidney.

Dr. Tim Averch:

I know getting small has it's advantages, but probably only best if you're a comic book superhero.

Video moderator:

So, according to the applausometer ...

Dr. Wenqi Wu:

[inaudible 00:41:55].

Dr. Mitch Humphreys:

I'm going to speak over them for a second. I think that Dr. Averch brings up a good point and one of the guests pointed out that the size of the PCNL access really doesn't make a difference. There was a study by [inaudible 00:42:10] looking at 30-French versus 11-French showing no difference in scar or change in renal function based on the access. So I don't know if people saw that in the comments, but it's actually a really good paper.

Dr. Wenqi Wu:

... pain. That's when you'll get less complication, especially with two-layered metal suction sheath. We can do the procedure very quickly and also we separate the inflow and outflow, so you can use a bigger laser fiber to break the stone faster. Most importantly, we can remove the stone by suction. So compared with flushing the stone out, it would be more efficient.

Dr. Wenqi Wu:

We shouldn't forget that the patient had UTI and also diabetes. With negative suction, we can keep a lower intrarenal pressure and we keep the patient safer, so we can even do day-surgery for this patient. So, SMP is much safer and effective, but the lady wants to know what's the [inaudible 00:43:12] of SMP compared with other instruments. I don't know whether you guys want to know. If you guys also want to know, please select me for next round. Thank you.

Dr. Khurshid Ghani:

Thank you. So, we're going to discuss the surgical options, ureteroscopy, shockwave lithotripsy, PCNL and then we've got these surgeries. Does anyone actually know what we're talking about here? Does anyone actually know what an ultra or a mini or a super mini is? Are we serious? But this is not a game. This is serious. Every patient has to be treated with respect like you would your own mother. So let us meet this patient. We already heard from Dr. [inaudible 00:12:55], a 53-year-old female. Remember, she's a gynecologist, a 1.5 cm stone in the lower pole, Hounsfield unit 900. What is the best surgical option? Look at the AUA. The AUA says PCNL is not the recommended standard for stones less than 2 cm. If it's in the lower pole, shockwave lithotripsy should not be offered for stones more than 1 cm.

Dr. Khurshid Ghani:

EAU says the same thing. For lower pole stones more than 1 cm, don't do shockwave lithotripsy. Where's Dr. El-Nahas? You'll hear him speak soon to tell us about the wonders of shockwave lithotripsy. Look at this series that he published. 9.2% hospital admission rate after shockwave lithotripsy, and what was the major risk factor if you had an existing ureteral stent? And then here is the level one evidence, randomized control trial of ultra mini versus shockwave versus ureteroscopy. In this series, ultra mini had greater hospitalization and more complications and ureteroscopy was the best treatment option for 1 to 2 cm lower pole stone.

Dr. Khurshid Ghani:

Let's ask us in the room, in this survey again from Dr. El-Nahas, when urologists were surveyed, for the 1 to 2 cm stone, ureteroscopy was the number one choice. Overtook PCNL. So on this basis, I would submit to you that this is the primary treatment modality and we should follow it. Thank you.

Dr. Agrawal:

Seeing is believe. You need to have a look at how ultra mini PCNL effectively clears up the stone using high-powered laser very efficiently and very quickly, irrespective of the stone density and the stone size. You can fragment the stone completely in an atraumatic fashion without causing any bleeding, without causing any injury to the pelvic collection system. There is high flow, low pressure at work, so there is no risk of sepsis. The stone gets dusted and fragmented and the fragments keep coming out spontaneously through the water jet effect. So there is very little risk of sepsis. There is hardly any bleeding. There is no risk of infundibular injury. At the end, you get a completely clean pelvic collection system with no residual. One-step, one-stage procedure, no tubes and no need for any stenting. In the end, you get a completely clean field. No need for any come backs. Thank you.

Video moderator:

Thank you very much.

Dr. Tim Averch:

Okay, great. Thank you. Alrighty, so I think it's time to be realistic. We're down to the final three here. If you're stuck on an island ...

Dr. Khurshid Ghani:

Look at Google. Ureteroscopy is the future, both for ...

Dr. Tim Averch:

... quote, "When the avengers needed help, they went big, they didn't go small." Thank you.

Video moderator:

Okay, thank you very much. So, according to the votation, Dr. Averch is out. Thank you very much.

Dr. Khurshid Ghani:

Thank you. "In every patient I see my mother, and in every relative I see myself." We just wrote this article about why we should do 1.5 cm lower power stone with ureteroscopy and we identified the development of single use devices, better lasers, better fibers and level one evidence is that it's no different to PCNL or URS when it comes to stone-free rates, but it has much lower morbidity. Just published this month, another RCT comparing mini PCNL with ureteroscopy, no differences. The only thing is ureteroscopy was superior to PCNL. Ureteroscopy had the same OR time, but definitely lower complication rates. Remember, the patient is a gynecologist. We all know that when we operate on doctors, they get all the worse complications. So, Guido is now wondering, hmm, I wish I had read this nice paper, Khurshid, now I need to get a new job.

Dr. Khurshid Ghani:

We are on a journey that began in 1880 when Sir Henry Morris published his results on open nephrolithotomy and this is his quote from his Hunterian lecture. "It thus became the starting point of both the development and the conservatism of renal surgery, which I8 am persuaded will become more and more conservative in the future." In 1880, he prophesied the death of his own operation.

Dr. Khurshid Ghani:

Look at Google. "Ureteroscopy is the future, both for patients and for physicians." Highest number of search hits.

Dr. Khurshid Ghani:

(silence)

Dr. Mitch Humphreys:

I think what he's showing here is the difference in the laser techniques, fibers and some of the new technology that we're seeing now the thulium laser, which hopefully we have a little bit of time to comment on here in just a second. I want to make sure we get this last talk in and then we'll open it up to the panelists for some concluding thoughts.

Dr. Agrawal:

Friends, the biggest fear about PCNL is invasiveness and complications and injury. Now, look at this exhibit from ultra mini PCNL. After completing of clearance, which I just showed you. And you can see how atraumatic this procedure is. There is no bleeding from the kidney. This is the short, small tract, which is just about 3 mm or 3.5 mm in diameter. So the nephroscope and the Amplatz sheath is coming out under vision. This tract will close down and heal in less than 24 hours, and at the end of it ... We are doing it very slowly, just to show you how atraumatic it is. Now, this is the surface wound. No bleeding inside, no bleeding outside. All you need to do is put a small Band-Aid and the patient goes home the next morning. Does not require to come back to you. No sutures. No stent. No residual stone. No secondary procedure. No bleeding. That's the end of the story.

Dr. Agrawal:

So, I submit you to that contrary to the widely held perception, an ultra mini PCNL is probably less invasive than even flexible ureteroscopy where you have to go up all the way, urethra, bladder, ureter to the kidney. The amount of trauma, the amount of risk of sepsis, the invasive of ureteroscopy, I would say is no less than that of PCNL, if not more. Thank you so much.

Video moderator:

So, according to the applausometer, Dr. Agrawal ...

Dr. Mitch Humphreys:

I'm going to pause here, because we've got about five more minutes of the Webinar to go through and then we'll get back to answering some of the audience questions. Just so everybody knows, the ultra mini PCNL was the winner according to applause. I think that I would love to hear some concluding thoughts from the panelists in terms of do you agree with the treatment, what would you do different? One thing that we didn't really get into the debate was antibiotic use perioperative, one week beforehand, two days beforehand, just perioperative, so maybe if you could give us concluding thoughts and maybe tell us a little bit about your antibiotic practice for these kind of complicated diabetic, obese, infected patients, that'd be great. So, we'll start with you, Dr. Knudsen.

Dr. Bodo Knudsen:

All right, so antibiotics obviously driven by preoperative cultures. If cultures are negative, then we just give Unasyn and gen at the time of the procedure. For a positive culture, then we would treat them ahead of time. There is still controversy how many days before. I think realistically two to three days before to get the urine negative is probably going to be reasonable in most cases. In terms of the outcome, I think this was interesting in that we had all these different perc groups. I think ultimately if you had sort of the perc army as one, I think they would have really dominated this debate, but you kind of spread out the votes amongst the different techniques. I think it comes down to what technique you're comfortable with. I think whether you prefer mini, ultra mini or SMP really depends on the equipment you have available and your own expertise, but I think you can get pretty similar results and excellent results with all of those techniques.

Dr. Ben Chew:

I would say that the one thing we have to learn more in North America, is we have to learn more from Europe and Asia and other parts, where mini perc or super mini perc is much more common. This is the [inaudible 00:53:31]. I think Tim Averch, I think standard PCNL got voted out because this is not a 3.5 cm stone, it's 1.5 cm. So a 30-French hole for that is probably a little bit overkill in doing something smaller. Like Bodo said, having the equipment available to you and your expertise I think is the main thing that really should be driving this. But I think in North America we need to be more accepting of these differences.

Dr. Mitch Humphreys:

I think these are all great comments. It's a great debate. I think we can listen to the concluding comments and the winner again was announced as the ultra mini perc as the winner. But before we go to that and we cut out, I would like to thank the Endo Society. I would like to thank Cook for their sponsorship. I would like to thank all the IT behind the scenes that makes this go so seamlessly and I'd importantly like to thank your panelists, Dr. Chew and Dr. Knudsen, for their expertise as we weigh in on this and look forward to other education events. So, we'll play out with the final comments here from the debate.

Video moderator:

... won the balloon debate. Congratulations.

Video moderator:

So, if I can make a final comment, I would say that we are witnessing a decline in ESWL, at least among our treatment options. Having said this, I can tell you this story. In Italy, one of the most prominent percutaneous surgeons had renal stones two years ago and he underwent ESWL. He didn't choose for PCNL on himself. And then, second comment, is that endourology is never black or white. it's different degrees of gray and I think that a modern endourologist would be familiar with all of these techniques, because only in this way you can select every time the best procedure for this stone. Because I think that this is a big mistake that is done very frequently, at least in Italy, that you perform for example only flexible because you are not able to perform PCNL. And this is really a misleading point. Thank you very much for your attention.

Dr. Mitch Humphreys:

So, with that, again, I think that keeps us on time for your Webinar. We thank you for your attendance and we thank the Endo Society. We thank our panelists and hope you all have a great day and thank you for your time.

Dr. Ben Chew:

Just to remind everyone, you will basically be directed to a feedback form immediately after the seminar ends, and then at the end of each month Michele Paoli will be sending you an email in order to get your CME events. Please sign up on the endourology.org website for next week. We've got robotic nephroureterectomy with a terrific panel. We again would like to thank Cook for their support for this current Webinar. Thank you very much.

Dr. Mitch Humphreys:

Great debate and great talks. One thing that we didn't really get into in the debate and the talks as we went through is any consideration in terms of cost. So I would like to hear your all's thoughts on cost of equipment, cost of procedure, maybe length of stay and how that can potentially play into the decision and how you feel about that. Dr. Knudsen, you want to start us off?

Dr. Bodo Knudsen:

Yeah. I think cost is a very important issue. A lot of times the US market kind of gets pinned as we can do anything we want, but I would say cost is being looked at scrutinized here much more than it ever has been in the past, and certainly internationally it's important. So that's kind of the beauty right now with mini PCNL is it is a lot of reusable equipment. The dilators and sheaths are reusable. So there's substantial cost savings. We keep our patients as mainly overnight stays, so they're not inpatient. So that's a cost savings. We send them out of the hospital, a majority of the time, without a stent. I think that's both a quality of life issue, but also cost savings because they don't have to come back for another stent removal procedure.

Dr. Mitch Humphreys:

Ben, your thoughts?

Dr. Ben Chew:

We don't have mini PCNL here. We are getting that equipment soon. So I don't really have that kind of thing, but certainly I think not using a balloon, using reusable metal dilators is important. I think Dr. Khadgi talked about using pneumatic LithoClast which of course has very ... It's completely reusable. You can use it thousands of times. I think it's fairly effective, but I think most of us would probably use laser for the most part and ultrasonic lithotripsy for bigger PCNL, and depending on whether or not you can use a reusable laser fiber. But I think outside of the US, a lot of places will actually use reusable laser fibers. We here in Canada do that in a lot of passes as well, including my center. So I think if you can cut down those costs, I certainly think that would be an issue. Something you need to consider is what you have access to, what can our system afford, especially if you're doing a lot of these cases. And I would argue that shockwave lithotripsy in Canada is substantially more cost effective than it is in the US, too. It's much cheaper here than it is in the US.

Dr. Mitch Humphreys:

One thing for cost we didn't really talk about was the reusable versus the single use ureteroscopes. Lately, we've seen a huge boom in this market and different manufactures. Everybody's getting into the single use ureteroscope game. Thoughts on cost effectiveness between single use versus reusable for ureteroscopy?

Dr. Bodo Knudsen:

It depends and you have to look at your local economics. I think there's definitely pros and cons. I think your center did a great study looking at volume and how that factors in. I think it's a much more complex issue when it look at it than it appears to be on the surface. Because it's not just the cost of the scopes, it's everything that goes with it. So it's a tricky one and you really have to evaluate your own center.

Dr. Mitch Humphreys:

A couple great points were brought in, and for me, in my hands, the thing that's made mini PCNL inject in the practice has been the laser technology, the advances in the laser platforms and technology, because it really smooths out these procedures and you no longer have to go about that. The other thing I would say I would love to get our thoughts as a panel on the topic of lasers. One thing I will comment about the techniques, a standard PCNL is a completely different technique than a mini PCNL. The sheath is your instrument. All the things you're taught not to do with a standard PCNL you try to do with a mini PCNL, and I just want to bring that point out, because I don't think it came out in the debate. But at least for me during my learning curve, that was a huge difference maker in efficacy. So, Bodo, I know that you teach and you do a lot of these mini PCNL, and as Ben said, he's waiting on the equipment, I'd love to get your opinion on that and then I would love for the panel to weigh in on thoughts on laser platforms and technology.

Dr. Bodo Knudsen:

I think that's a really, really good point to make. It's not just a perc with a smaller tract. The technique is different. The approach is different. Even where you're going to gain access may be different. So I think it's a mistake for people who are used to doing full size percs to go and do a couple minis and think, hey this really isn't any better and in fact it's awkward and I'm struggling with it. There is that learning curve and you need to get through it and certainly picking up some practical tips from people and things can be really helpful. I think one of the underrated things, and there was a comment in the chat towards the end about posterior access to get to an anterior calyx. With a mini set, it's so much easier to move around the kidney with that small scope. You can get to places you can't normally get and you're not going to tear up that infundibulum like you might with a big nephroscope that's pretty easy to do to accidentally run that scope or cut the infundibulum with the edge of the scope with the big one. With the mini it's much easier to get around.

Dr. Bodo Knudsen:

I think that's an underrated benefit. When you think about patients who have percs, how many of them have multiple percs in their lifetime and have multiple tracts and have multiple opportunities to cause more trauma. So I think that's where a mini also is of value. I had [inaudible 01:02:20] who's had so many different surgeries, and I think mini is ideal because we get them stone-free but we're not causing as much trauma along the way.

Dr. Mitch Humphreys:

It brings up a really interesting point, because my gateway into the mini PCNL was the big staghorn calculus and I'd put my main tube where I wanted to and then I'd mini perc into the other calyces where I couldn't get there with flexible, because sometimes that happens. The other thing that I noticed from that experience was sometimes with mini in these hypermobile kidneys for very skinny patients, sometimes you almost have to pin the kidney down with your tube or your access and then get your access where you need to be. There's been times where I've had to use one needle to hold the kidney while I get my ideal perfect access with another one, which is another interesting kidney. Ben, do you [crosstalk 01:03:08]?

Dr. Ben Chew:

When you do that, Mitch, what size needle do you put in to hold it, and where do you put it?

Dr. Mitch Humphreys:

Basically what I do is when the kidney is so mobile, because I've had some ... Unfortunately, I don't get enough of the skinny hypermobile kidneys that I would like to, but when I do get them, a lot of times when I try and access that lower pole, that lower pole almost rolls away and the configuration completely changes for the access point. So then what I will do is I will go in the middle of the kidney, or wherever I can, but sometimes in the middle of the kidney where there's a stone. I'll put it there and take care of that, and if that doesn't do it for me, I've got a pen and then I use that and then I go into the lower pole and that holds that kidney in place. I don't do it very often, but it is a nice tool to have in your armamentarium instead of getting frustrated and going the other way. What I will say is your point about doing them supine and having access to do flexible ureteroscopy in some of those situations probably makes that technique not as important, but when somebody doesn't have the ability to have flexible ureteroscopy concomitantly with a PCNL procedure, I have used that in the past to make sure that I've been able to get access.

Dr. Bodo Knudsen:

The other option, sort of shout out to Dr. [inaudible 01:04:19], is retrograde PCNL. So other tract out in a mobile kidney can work really well. So it's something to keep in the back pocket. I think Cook still makes the Lawson kit, which can be used for that.

Dr. Mitch Humphreys:

Well, let's spend a little bit of time on lasers. Certainly the thulium fiber laser is making a lot of noise in the marketplace right now. It's kind of disrupting things in terms of dusting. It's taking people that have been stone fragmenters and turning them into stone dusters from a technical standpoint. So I would love to hear your thoughts between Moses, the new high power Moses 2.0 up to 120, versus the thulium fiber laser. And maybe for the audience some differences between a thulium laser and a thulium fiber laser, because they definitely aren't the same thing.

Dr. Bodo Knudsen:

Obviously we've been using holmium for close to 20 years now. It's been a great laser. It's been the gold standard. There's been some refinements going from short pulse to long pulse was probably one of the better refinements that we saw along the way. It really changed retropulsion, being able to keep that stone stable. It keeps your fibers from burning back as much. Then we saw the leap to Moses with the pulse modulation. I would say that was a much smaller jump, compared to short pulse to long pulse.

Dr. Bodo Knudsen:

Our own experience with Moses hasn't been great. We've had a lot of problems with reliability, but that may be just isolated to our own experience. But certainly it's been a refinement. I think thulium fiber we've talked about in other Webinars, but the advantage there is now you've got a very small portable laser that can be plugged anywhere. You can move it throughout your hospital. Still uses fairly inexpensive silica fibers with it, but now you have this whole new world of this super high pulse frequency. So instead of 80 Hz at the maximum, we're talking 2000 Hz. I think that is where a lot of work is going to be done looking at fragment size and true dusting and maybe not having to do all the other ancillary things we were doing with ureteroscopy. We might cut down on the number of sheaths we need. We may not need to use as many baskets and hopefully still have equivalent outcomes. So potentially bring down cost. So I think that's the big change.

Dr. Bodo Knudsen:

I think the other important thing is not to get confused. Thulium YAG is the other thulium technology that's been around. Completely different. It's not comparable at all, so it shouldn't really even be thought of as the same. So thulium fiber is completely different technology than thulium YAG and are not interchangeable in any way.

Dr. Mitch Humphreys:

Ben, your thoughts?

Dr. Ben Chew:

The thulium fiber laser, and that's the only one I've used, I've not used Moses or any of the other pulse modulation except for maybe long versus short pulse on one of our lower power lasers, I think is really going to change things, and thulium fiber has changed things. With this, I feel like it is ... With regular holmium YAG, I'm always talking to the residents, it's basically a battle between trying to turn the energy down low enough so the stone won't move so much, but also trying to make sure that it still fragments. When you're fragmenting well, the stone's moving around a lot. When the stone is not moving around as much, you're not fragmenting as well. So it's always a balance between the two. And I think that thulium fiber laser really has sort of changed that sort of narrow therapeutic window, where suddenly the stone is not moving and you're getting great fragmentation efficiency, and I think it's because you have the low energy and you have the very high frequency up to 2400 Hz, depending on if you go down to a low enough energy. So I think for me I feel ... and it's been very fast as well too. So I feel that I can tackle bigger stones ureteroscopically than I have been with holmium, and I feel like I'm able to make finer fragments.

Dr. Ben Chew:

Now, I've not used Moses. That's my disclosure. But the other thing is that I think there's other things coming down the pipeline as well, too, for holmium YAG that are going to change things too in terms of pulse modulation or firing different amounts of pulses for each pulse in different energies. So I think we're going to see a bunch of differences as well, too. It's going to make flexible ureteroscopy even better.

Dr. Mitch Humphreys:

Yeah. I will say that as we did the dusting versus basketing trial and I was a very adamant basketer, fragmenting, no stone left behind, take all those fragments out, and I will say the new technology, both the Moses and the thulium fiber laser, has encouraged me to do more dusting. Now I'm going to say I'm a duster by any stretch of the imagination, but I will certainly take those on and have more freedom, because I think that you're getting a different quality of fragment. I think before the fragments that you were getting were larger and you could sometimes get other pieces of stone that would hide behind this sea of fragments. Now, you get such a fine dust that it's almost like a silt. And when you're irrigation is blowing, you're seeing these pillows and silt and you feel very comfortable in leaving that dust. What is that called? Almost like a visual shockwave where you're actually seeing it. So I've become a lot more comfortable, a lot more facile with these technologies. I think they're great enablers and they're really going to push what we're able to do endoscopically, and I think there's a use for them even with mini PCNL. I find that I use them quite often.

Dr. Ben Chew:

What would you have picked for this patient?

Dr. Mitch Humphreys:

You pinned me down eventually. Again, for this particular patient, being a physician, diabetic, with some of those things and worried about the infectious risks, in my hands, because that stone was mobile and moving around, I probably would have done ureteroscopy because of the thickness of the parenchyma of that kidney and the lie and some of those things. She leaves the same day, she's back at work. With some of these new scopes, the P7 and some of these other ultra small scopes, you can do a whole lot and not even have to leave a stent necessarily all the time. If I leave a sheath, I for sure would leave a stent. But if I didn't leave a sheath, then I wouldn't necessarily have to leave a stent in this patient. But on my end, I probably would have done a ureteroscopy, even though I enjoy percs an awful lot.

Dr. Mitch Humphreys:

So that brings us to the final. Anybody's final thoughts on this patient or the cases or the debates as we wrap it up here?

Dr. Bodo Knudsen:

It's interesting. We had ESWL, ureteroscopy and mini perc amongst the panel, so you can see that there's definitely different ways to approach stones. Certainly looking at your own local expertise and equipment are really important, and do both what you're comfortable with and what your patients are comfortable with.

Dr. Mitch Humphreys:

As Ben rejoins us, I think that for me the real learning point is you have to have an individualized approach to every single patient. There's no one size fits all, and you have to be malleable in your thought process and how to do those things. I think where people run into problems is where they always try and put that round peg into every hole, assuming it's going to be a round hole. And that's where complications come from, so I think you have to be able to modify your technique and have an armamentarium of techniques to pull from to do what's kind of best for the patient.

Dr. Mitch Humphreys:

Ben, we'll get your final thoughts here as we conclude.

Dr. Ben Chew:

I think that's exactly it. That's the real fun part about it too, is that we get to do different things for the exact same stone, but in different patients and in different locations, and I think we need to be malleable about it. I'm glad that mini perc and these other smaller types of perc are becoming more commonplace in North America, because we do need to accept them more, just like ultrasound guidance and everything else as well, too. So I think it's not a cookie cutter approach. In the further part of the video that we didn't see, Guido Guisti also says too, "Endourology is not just black and white." It's not like we just cut out a cancer and do this. I know there's nuances to that, too. But it's really just not all black and white. There's no cookie cutter approach. We need to be able to do a lot of different things, which I think is why it's such a fun job.

Dr. Mitch Humphreys:

All right, well again, thanks to the panelists. Thanks to the Endo Society. Thanks to Cook for your sponsorship. And thanks to all the IT and everybody behind the scenes that makes this look so good, helps deliver this educational content. So thank you all, have a wonderful day.