Choosing an Appropriate Length of Loop Type Ureteral Stent Using Direct Ureteral Length Measurement

The ureteral stent is now a fundamental part of many urological procedures. To decrease ureteral stent-related symptoms, loop type ureteral stent was developed. However the most important factor to decrease urinary symptoms is choosing the optimal length of a ureteral stent. We investigated the relationship between the actual ureteral length and the loop type ureteral stent position.A total of 226 loop type polyurethane ureteral stents (156 patients) were inserted with four options for stent length (20, 22, 24 and 26 cm). The ureteral length was measured using a ruled 5-Fr ureteral catheter. The appropriateness of stent position was defined into three groups based on kidney-ureter-bladder films.Nine stents (3.9%) migrated, 171 stents (75.7%) were in the appropriate position and 46 stents (19.5%) were overlong. The rate of migration rate and overlong stents closely correlated with the ureteral length when the proximal end of the stent was in the renal pelvis.It is appropriate to choose a loop type ureteral stent that is the same or 1 cm less than the length of the ureter when the proximal end of the stent will be in the renal pelvis.