AUA 2017: Is Endoscopic Evaluation at the end of Retrograde Intra-renal Surgery a reliable Predictor of Post-Operative Significant Residual Fragments

Boston, MA ( A group of urologists from Italy performed a retrospective analysis of the utility in end-of-procedure endoscopic evaluation of stone fragments following ureteroscopy. They included retrograde intrarenal surgery for single large stones and stone requiring multiple procedures. Stone free rate was defined as < 4 mm.

The primary hypothesis of the study asked if end-of-procedure endoscopic evaluation was a reliable indicator of the presence of stone fragments at 2-3 week post-operative renal ultrasound. Their results showed an overall rate of concordance of 30%. In addition, residual fragments were underestimated with end-of-procedure endoscopic evaluation. When specifically analyzing the experience of the surgeon and the primary outcome, they found that the experienced expert urologist (a cohort with the most procedures during the study period) improved the ability to endoscopically estimate the number of fragments at 2-3 week renal ultrasound compared to urologists with less experience.

A comment following the presentation raised an important point regarding renal ultrasound (US). Specifically, renal US often can overestimate the size and number of stone fragments remaining post-operatively; therefore, US may not be an ideal comparative imaging modality in addressing their hypothesis. Dr. Bosio reiterated that their facility does not encourage repeat CT, an imaging modality that would be superior to US in this case, and has inherent radiation exposure risk. Moderators suggested a prospective study may be required to develop a standardized technique for end-of-procedure endoscopic evaluation and fully address the reliability and predictability of the technique and stone-free rate following ureteroscopy.

Presented by: Dr. Andrea Bosio, MD

Authors: Andrea Bosio, Eugennio Alessandria, Ettore Dalmasso, Dario Peretti, Federico Vitiello, Alessandro Bisconti, Paolo Destefanis, Paolo Gontero

Affiliation: Turin, Italy

Written By: Daniel Lama for

at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA