ABSTRACT Purpose: We aimed to compare the success and complication rates of the anterograde and retrograde Ureterorenoscopy (URS) for impacted upper ureteral stones in patients > 65 years of age. Materials and Methods: Data of 146 patients >65 years of age and underwent anterograde URS (n=68) in supine position or retrograde URS (n=78) for upper ureteral impacted stones>10 mm between January 2014 and September 2018 were collected prospectively. The groups were compared for success and complication rates, duration of operation, hospital stay, and ancillary procedures. Results: Anterograde and retrograde URS groups were similar for demographic and stone related characteristics. The success rate of the anterograde URS group was significantly higher than the retrograde URS group (97.1% vs. 78.2%, p=0.0007). The complication rates were similar for the two groups (p=0.86). Clavien grade I and II complications were observed in 3 patients in each group. The mean hemoglobin drop was 0.5 g/dL in the anterograde URS group and blood transfusion was not performed in any of the patients. The mean duration of operation was 41.2±12.5 minutes in the mini-PNL group and 59.6±15.1 minutes in the RIRS group and the difference was statistically significant (p=0.02). The median duration of hospitalization was 1 day for both groups. Conclusions: Performing anterograde URS in supine position provided better success rates and similar complication rates compared to retrograde URS. Based on these results anterograde URS shall be considered as one of the primary treatment options for management of impacted upper ureteral stones in the elderly population.

ABSTRACT Introduction: The main aim of stone surgery is to establish stone free status. Performing flexible nephroscopy is an effective tool in this manner. The aim of this study was to evaluate the role of retrograde flexible nephroscopy for detection of residual fragments following percutaneous nephrolithotomy (PNL) in comparison with antegrade approach. Materials and Methods: Data of 137 patients underwent ECIRS was collected prospectively. In all cases following stone clearance, collecting system was checked for residual fragments. First antegrade than retrograde flexible nephroscopy was performed and success rates to reach all calices and detection of residual fragments were noted. All patients underwent CT and success rate of antegrade and retrograde approaches were compared. PPV and NPV of retrograde approach to detect residual fragments were calculated. Results: Antegrade and retrograde nephroscopy successfully accessed all of the calices in 101 (73.7%) and 130 (94.9%) patients respectively (p<0.0001). Residual fragments were observed in 18 (13.1%) patients following antegrade flexible nephroscopy. Retrograde approach identified residual stones in 17 more cases. These cases were treated with flexible nephroscopy or secondary percutaneous tract. Postoperative CT revealed residual stones in 10 (7.3%) patients. PPV and NPV of retrograde flexible nephroscopy were 83.3% and 96.2%. Conclusions: Flexible nephroscopy effectively detects residual fragments following PNL. Retrograde approach was more successful than antegrade approach to reach all calices. We recommend performing retrograde flexible nephroscopy following PNL especially in complex cases as it has the potential to increase SFR, decrease the need for second look surgery and unnecessary postoperative imaging.