Expert describes miniPCNL technique for pediatric stone disease

In this video, John Michael DiBianco, MD, discusses describes how he performs miniPCNL in pediatric patients. DiBianco is an assistant professor of urology at the University of Florida, Gainesville.

Transcription:

Like anything else, anytime we do a PCNL, we're going through the skin, through the back into the kidney, we always get a CT scan. That's pretty standard. One, that's helpful for me because it classifies stone volume, maybe even density, all that kind of stuff. But it also shows me, do I have a window, is there an area that I actually can safely do this without hitting other things that might be in the way, like bowel, spleen, some of the other things where you don't want to make a hole. So we always get that, and as long as there is a window, we've been pretty successful in performing the procedure. We typically set them up in this modified supine position where they have the same side that we're operating on, that leg stays straight, and the other leg is in a stirrup so that we actually have access from both below, like a normal ureteroscopy-type of positioning, but also the flank, where we're going to be doing the majority of the percutaneous work. I use x ray, I use fluoroscopy. That's just the way I was trained; that's the way I'm comfortable. We use as low a dose as possible, because obviously, these are younger patients, so certainly it's a higher concern, at least of mine, on how much radiation they're getting. There are some colleagues that I'm aware of out there that are using no fluoroscopy and no x ray; they use ultrasound. I'm not as comfortable with that, so I don't do that. But it's certainly been described. We use a small catheter in the bladder, in the ureter to inject contrast into the kidney. We use that contrast and an x ray and fluoroscopy at the same time, to see where on the skin, we enter with a needle in order to get into the kidney in the appropriate position. We use a lot of these different things to see what's the best place to enter, what's going to be the safest, and what's going to be most successful where we only need to make 1 puncture in the kidney. And then once we've done that, and we're successful with it, we decide, usually preoperatively based on the stone volume, how big we're going to make that hole. Miniaturised PCNL can be anywhere from 22 French down to 12 French, so it's a very wide range that we potentially have the access to. We use one of the kits, one of these tools that has several different sizes. Most commonly, I use an 18 or 16 French access, but it's really dependent. When you look at our series, we've treated about 8 patients so far. One patient we did it on both sides, so 9 renal units overall, and we've gone anywhere from 16 French, all the way to 20 French, with our sizes, so it really just depends. Once we do that, then we start working and usually the stone breaks up very nicely, and we can take everything out through that access, and they don't need anything else through that hole so we can close it up. And we typically also, as long as the ureter allows it, we can put a scope in from below because of that positioning, we can easily reach between the legs and at the flank. And we'll search the rest of the kidney ureteroscopically just to make sure we don't miss anything. Then we leave a stent afterwards. Sometimes, we leave it on a string so that the patient can take it out at home a week later or so, depending on the family's comfort level, the patient's cooperability, depending on their age. We've been pretty successful here. I think what's nice too about that positioning, a lot of times historically, we would do percutaneous surgery with the patients on their front, so they're kind of in a Superman/Superwoman position. Sometimes, if you run across issues, like a stricture or some sort of anatomical problems, it's a little bit harder to do your typical endoscopic ureteroscopic techniques in that position. What's nice about that the modified supine position is that you kind of have all of those techniques and tools available in case you have to. In the pediatric population, we don't tend to see a lot of stones, thank goodness, but when you do, there's usually a reason. And a lot of times, it's anatomical. So I think it gives us the ability to do other things that might be necessary in order to treat that patient and that stone. I can think off the top of my head about 3 of the patients had ureteropelvic junction obstruction, whether it's stricture or what have you, that we had to treat concomitantly, along with the stone. Some of them have altered anatomy, double ureters, duplex systems, and so forth. So, it gives us a lot of adaptability to change the operation to suit the patient, rather than forcing the same operation on a wide variety of clinical scenarios.

This transcription was edited for clarity.