Optimal prevention and management of proximal ureteral stent migration andremigration

Purpose: We evaluated issues associated with proximal ureteral stent migrat ion and remigration, including causes and management, and the predictabilit y of ureteral length. Materials and Methods: All proximal ureteral stent migrations that occurred from January 1997 to March 2000 were reviewed. Characteristics and treatme nt of the 33 patients with proximal ureteral stent migration were compared with those of 66 randomly selected controls who did not have stent migratio n. We also analyzed a subgroup of 6 cases of remigration. Results: Of the ureteral stents 2% migrated proximally. Mean height was gre ater in patients with versus without a migrated stent (p = 0.028). The sten t-to-ureter length ratio was lower in the migrated than in the nonmigrated group (p <0.0001). Patient height and side of migration were significant pr edictors of ureteral length (R-2 = 0.3511, p <0.0001 and 0.0007, respective ly). Of the patients who required continued ureteral stenting migrated sten t management included placement of a longer stent in 9 (group 1) and a sten t of equal length in 4 (group 2), and repositioning of the original stent i n 4 (group 3). There was no remigration in group 1. However, migration recu rred in 2 patients in group 2 (50%) and in all 4 in group 3 (100%). Conclusions: Proximal migration occurs when a stent is too short for the ur eter. We recommend that ureteral length should be measured directly from an x-ray to select the optimal stent length. If it is necessary to continue s tenting a ureter after migration has been detected, a longer stent should b e placed.