Presentation Authors: Ohad Kott*, Alison Chambers, Osama Al-Alao, Eric Jung, Timothy O'Rourke, Meredith Wasserman, Alejandra Balen, Mina Ghaly, Timothy Wright, Stefan Rodriguez, Siddharth Marthi, Christopher Tucci, Gyan Pareek, Providence, RI
Introduction: Ureteroscopic laser lithotripsy (URSL) has become the most common form of surgical management of kidney stones in the United States. Intraoperative residual stone burden evaluation (IRSBE) is an important technique that allows the surgeon to interpret the success of the procedure. Routinely, urologists perform postoperative imaging to assess for residual stone burden and/or silent hydronephrosis. We evaluated the correlation rate between IRSBE and postoperative imaging and postoperative adverse clinical outcomes. We sought to compare the predictive value of IRSBE and postoperative imaging (PI) on postoperative adverse clinical outcomes.
Methods: A total of 187 adult patients who underwent URSL during a 6-month period between March 1, 2017 and September 1, 2017 were included in the study. Clinical and PI data, including unplanned visits to the emergency department, readmissions and stone surgeries were retrospectively collected by medical record review. Two different methods were utilized to assess residual stone burden: IRSBE and postoperative imaging with ultrasound or computed tomography. Stone size was measured using the largest dimension. Stone burden was calculated by adding stone sizes of all locations. Intraoperative stone free status was defined as complete stone dusting or removal of all stone fragments >3mm. Postoperative stone free status was defined as the absence of residual stone fragments (0 mm) on PI.
Results: Study cohort characteristics are described in table 1. Despite differences in determinted stone free status between IRSBE (70%) and PI (54.8%), only 12 (6.4%) patients required postoperative procedures and only 6 (3.2%) required URSL. Residual stone on postoperative evaluation or postoperative imaging did not predict postoperative encounters or stone surgeries.
Conclusions: In this study, there was poor correlation in stone burden evaluation between IRSBE and PI. Despite the low PI stone free rate, auxiliary treatments rate was low. Dusting at the time of URSL with IRSBE appears to be an effective method of determining clinical outcomes despite poor PI stone-free rates. â€ƒ