Can negative ureteroscopy be predicted in ureteral stone treatment?

We aimed to evaluate factors predictive of negative ureteroscopy (URS) in ureteral stones.

Patients who underwent URS between January 2007 and June 2018 were included in the study. Patients were divided into two groups: group 1- positive URS (841 patients); and group 2 -negative URS (75 patients). These two groups were compared in terms of demographic data, stone characteristics, and postoperative outcomes.

The mean age of the study patients was 44.5±15.1 years. The absence of collecting system dilatation due to the present stone was found to be a significant predictive factor for negative URS in univariate analysis, but there was no significant difference in multivariate analysis. In the multivariate analysis, low body mass index (BMI), no history of stone surgery, stone located in the distal ureter, small stone area, longer time between the last imaging procedure and URS, and medical expulsive therapy (MET) application were statistically significant in predicting negative URS.

In this study, the parameters that significantly predicted negative URS were found to be low BMI, no history of stone surgery, distal localization of the stone, small stone area, longer time between the last imaging procedure and URS, and MET applied for the current stone. These parameters should be considered to avoid negative URS and patients should be informed of the possibility of negative URS prior to operation.