#WCE2014 - Direct endoscopic visualization combined with ultrasound-guided access during percutaneous nephrolithotomy - Interview

TAIPEI, TAIWAN (UroToday.com) - Introduction and Objectives: PCNL access is challenging and requires significant radiation exposure. In an attempt to reduce radiation exposure, we employed a novel technique combining direct ureteroscopic visualization of access location with ultrasound guidance.

wceMethods: Fluoroless ureteroscopy allowed selection of the optimal calyx for access. Percutaneous ultrasound guidance was used to advance a Chiba needle into the desired calyx identified using deflection of the ureteroscope tip. A wire was then ad- vanced into the calyx and pulled into the ureter using a basket. Balloon and nephrostomy tube placement were performed under ureteroscopic guidance. 20 consecutive patients undergoing this technique were matched against 20 patients who had undergone conventional fluoroscopic access. Outcomes compared were fluoroscopy time, operative time, EBL, stone free rates and complications. Mann-Whitney U and Pearson Chi-square tests were used for comparisons, with p < 0.05 considered significant.

Results: Using this novel technique, mean fluoroscopy time needed to obtain access was 3.5 seconds (0–27.9), mean total fluoroscopic time was 8.8 seconds (0–47.1), mean operative time was 233 minutes (87–533), EBL was 111 ml, stone free rate was 65% and complications were 25%. Comparing these 20 patients to 20 matched conventional PCNL patients, there was no difference in operative time (p = 0.76), EBL (p = 0.64), stone-free rates (p = 0.52) or complications (p = 0.71). However, the novel technique resulted in significant reduction in fluoroscopy time to achieve access (3.5 vs.915.5 sec; p < 0.001) and total fluoroscopy time (8.8 vs 1028.7 sec; p < 0.001).

Conclusions: This study demonstrates the feasibility of combined US and ureteroscopic assisted access for PCNL. In addition, a > 95% reduction in fluoroscopy time was achieved using this technique.

Source of Funding: None

Listen to an interview with D. Duane Baldwin, one of the authors of this study.


Presented by Muhannad Alsyouf, Roger Li,
 Michelle Lightfoot, Edna Miao, Albert Lee, Jason Smith, Evan Lehrman, Kristene Myklak, Javier Arenas, Gaudencio Olgin, Nazih Khater, and D. Duane Baldwin at the 32nd World Congress of Endourology & SWL - September 3 - 7, 2014 - Taipei, Taiwan

Loma Linda University Medical Center, Loma Linda, CA USA