Randomized controlled trial comparing three different modalities of lithotrites for intracorporeal lithotripsy in pcnl

Purpose: To compare the efficiency (stone fragmentation and removal time) and complications of three models of intracorporeal lithotripters in percutaneous nephrolithotomy (PCNL). Materials and Methods: Prospective, randomized controlled trial at nine centers in the North America from 2009 to 2016. Patients were randomized to one of three lithotripter devices: the Cyberwand, a dual probe ultrasonic device; the Swiss Lithoclast Select, a combination pneumatic and ultrasonic device; and the StoneBreaker, a portable pneumatic device powered by CO2 cartridges. Since the StoneBreaker lacks an ultrasonic component, it was used with the LUS‐II ultrasonic lithotripter to allow fair comparison with combination devices. Results: 270 patients were enrolled, 69 were excluded after randomization. 201 patients completed the study: 71 in the Cyberwand group, 66 in the Lithoclast Select, and 64 in the StoneBreaker group. The baseline patient characteristics of the three groups were similar. Mean stone surface area was smaller in the StoneBreaker group at 407.8mm2 vs 577.5mm2 (Lithoclast Select) and 627.9mm2 (Cyberwand). The stone clearance rate was slowest in the StoneBreaker group at 24.0 mm2/min vs 28.9 mm2/min and 32.3 mm2/min in the Lithoclast Select and Cyberwand groups respectively. After statistically adjusting for the smaller mean stone size in the StoneBreaker group, there was no difference in the stone clearance rate among the three groups (p=0.249). Secondary outcomes, including complications and stone free rates, were similar between the groups. Conclusions: The Cyberwand, Lithoclast Select, and the StoneBreaker lithotripters have similar adjusted stone clearance rates in PCNL for stones > 2cm. The safety and efficacy of these devices are comparable

Flexible ureteroscopy: Technological advancements, current indications and outcomes in the treatment of urolithiasis

The last 3 decades have witnessed great improvements in the technology and clinical applications of many minimally invasive procedures in the urological field. Flexible ureteroscopy (fURS) has advanced considerably to become a widely utilized diagnostic and therapeutic tool for multiple upper urinary tract pathologies. The most common indication for fURS is the treatment of upper urinary tract stones with the aid of Holmium:Yttrium Aluminium Garnet (YAG) laser lithotripsy. Advancements in endoscope technologies and operative techniques have lead to a broader application of fURS in the management of urolithiasis to include larger and more complex stones. fURS has proved to be an effective and safe procedure with few contraindications. Continued progression in fURS may increase its clinical applicability and supplant other procedures as the first line treatment option for urolithiasis

Standardizing the reporting of percutaneous nephrolithotomy complications

Accurate reporting of complications is an essential component to critical appraisal and innovation in surgery and specifically with percutaneous nephrolithotomy (PCNL). We review the evolution of complication reporting for PCNL and suggest future directions for innovation. A selective review was carried out using Pubmed. Key search terms and their combinations included percutaneous, anatrophic, nephrolithotomy, PCNL, complications, Clavien, Martin score, bleeding, bowel injury, perforation, fever, sepsis. The references from relevant papers and reviews as well as AUA and EAU guidelines were also scanned for inclusion. PCNL has become the procedure of choice for large renal stones owing to decreased morbidity over alternative procedures. Both common and rare complications have been described in large case series, small randomized controlled trials, and case reports in an unstandardized form. Although these reports have provided an informative starting point, a standardized complication reporting methodology is necessary to enable appropriate comparisons between institutions, time periods, or innovations in technique. The Clavien-Dindo grading system has become widely accepted in urology and has facilitated the study of PCNL complications. Future research should focus on adaptions of this system to render it more comprehensive and applicable to PCNL

Probiotics for the developing world

Ureteral stents are commonly used in urology to drain urine from the kidney. An important complication arises when bacteria or encrustations adhere to the surfaces, causing infection and/or blockage of urine flow. It was hypothesized that upon exposure to urine flow, host elements are deposited as a conditioning film onto the surface of the materials, changing their characteristics. This was studied by x‐ray photoelectron spectroscopy analysis of stents removed from stone‐forming patients and in a stent incubated in vitro with urine. In addition to nitrogen being adsorbed, there was evidence of additional carbon compounds bound to hydroxyl and carboxyl and on some stent surfaces calcium and phosphorus were detected. When a stent was incubated in vitro with urine, nitrogen adsorbed along with a new type of carbon compound bound to hydroxyl. Scanning electron microscopy showed the presence of extensive bacterial biofilms, even after antibiotic therapy, and the existence of tears, erosions or abrasions in the stent surfaces within 2 weeks of implantation. Energy‐dispersive x‐ray analysis confirmed the presence of calcium, magnesium phosphorus and carbonate apatite crystals. These findings have important clinical implications. Copyright © 1994 John Wiley & Sons Ltd

Pathogenesis of urinary tract infection in the elderly: the role of bacterial adherence to uroepithelial cells

This review focuses on the biomaterials used in urology, in particular, the properties of urethral catheters and ureteral stents currently being used in clinical practice. The importance of biomaterial type, biocompatibility, and encrustations are discussed and explained. Current management of bacterial infection and the importance of biofilms are presented, with recommendations based on published information