Endourology/Stones: Reusable, disposable ureteroscopes compared

A mobile app for stone metaphylaxis and an algorithm defining specific indications for stent omissions were among the other highlights in endourology/stones at AUA 2018. The take-homes were presented by Zeph Okeke, MD, of Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY.

• A comparison of disposable and reusable flexible ureteroscopes found that the disposable scopes seem to have better in vitro deflection but that when thicker, less flexible tools occupy the working channel, the reusable scope deflects better.

• In a clinical study, the MOSES Pulse holmium laser was associated with significantly lower fragmentation and procedural times and significantly less retropulsion of stones than a regular holmium lithotripsy mode, thus improving stone fragmentation efficiency.

• A prototype pulsed Thulium laser fiber demonstrated much more efficient fragmentation of human stones in an in vitro model compared to traditional holmium laser fibers.

• A novel dual-energy single-probe lithotripter had much more efficient stone fragmentation and clearance rates compared to currently available lithotripters.

• In patients undergoing percutaneous renal surgery, high frailty score was significantly associated with increased length of stay and presence of postoperative complications and was predictive of discharge disposition of the patient after hospitalization.

• Fluoroscopy-free retrograde intrarenal surgery was associated with short operative time and a similar stone clearance rate compared to conventional ureteroscopy with fluoroscopy.

• In a study evaluating whether coconut water consumption can prevent kidney stones, citrate excretion in patients consuming coconut water was markedly increased compared to patients consuming water alone.

• “StoneMD” is the first mobile application for stone metaphylaxis. The app appears to increase patient compliance with fluid intake but not necessarily with dietary intake.

• A review of a dial cup, smart bottle, and reminder band found that all three devices performed similarly in terms of helping patients increase their intake of fluids, and there was no significant difference among any of the three devices.

• A review of microbial diversity in genetic hypercaliuric versus standard rats found that for standard rats, the biodiversity of microbes within the gut was significantly greater than that for stone-forming rats. Furthermore, for the stone-forming rats, there was a preponderance of certain species of bacteria, the bacteroides genus specifically, which have been associated with the gut flora in stone-forming humans as well.

• For shock wave lithotripsy, variable frequency is a novel approach that can improve stone fragmentation but needs further evaluation in clinical studies.

• Researchers developed a highly accurate preoperative nomogram for the prediction of spontaneous passages of ureteral stones ≤10 mm using three readily available variables based on computed tomography imaging.

• An evaluation of participants in three regional courses on percutaneous nephrolithotomy found that approximately 25% of the participants applied what they learned from the courses into their daily practice.

• Following an algorithm defining specific indications for stent omission allowed researchers to avoid stents in approximately 42% of their ureteroscopic lithotripsy patients. There were no readmissions or secondary procedures as a result of avoiding stents in their group of patients.

• A systematic Cochrane review suggests ureteral stent placement does not decrease the number of unplanned return visits, decrease the number of secondary procedures, decrease the rate of ureteral stricture, or appreciably prolong operative time.