Two hundred and three adult patients who underwent ureteroscopy with laser lithotripsy and/or stone extraction were analyzed based on the type of uereteroscope used in their respective cases. Outcomes to be assessed included operative time, complication rates, stone free rates, and unplanned visit rates.
Of the 97 patients analyzed, 24 (24.7%) cases utilized DU. The DU group had lower stone free rates (15.8% vs 32.8%, p=0.09), and higher median residual stone burden (8mm vs 5mm, p=0.22), though these results were not significant. The intraoperative time for the DU group was also higher (34min vs 23 min, p<0.01). However it also worth noting that patient in the DU group had a higher median stone burden (15.5mm vs 9mm, p<0.01), and more frequently had ASA score ≥ 3 (50.0% vs 24.7%, p=0.02).
At first glance, these results suggest that DU ureteroscopes are not as effective as RU ureteroscopes and lead to worse clinical outcomes and complications. However, at baseline the patients who were in the DU group generally had higher stone burdens to begin with and a worse ASA score. During his presentation, Kott recognizes that this could be evidence of a selection bias – patients in the DU were more complex and possibly had worse prognoses – which led to these counterintuitive results. They hope to present newer data on a study that randomizes patients to either RU or DU use, to overcome the possible bias that might have occurred during this retrospective analysis.
Presented By: Ohad Kott, MD, Research Fellow, Minimally Invasive Urology Institute, The Miriam Hospital; The Warren Alpert Medical School at Brown University, Division of Urology, Providence, Rhode Island
Authors: Jorge Pereira, MD, MPH, Timothy Wright, Eric Jung, Meredith Wasserman, Alejandra Balen, Paul Bower, Mina Ghaly, Christopher Tucci, Gyan Pareek
Written By: Max Towe, medical writer for UroToday.com at the 36th World Congress of Endourology (WCE) and SWL - September 20-23, 2018 Paris, France