Purpose: The parameters responsible for proximal ureteral stent migration were quantitated.
Materials and methods: We compared 16 patients seen between 1990 and 1993 with stent migration to 32 patients whose stents did not migrate.
Results: The stent indwelling time and number of stents with a proximal curl of less than 180 degrees were similar between the groups. More patients with migration had stents that were shorter than the ideal length, with a distal curl of less than 180 degrees and a proximal curl in the upper calix versus the renal pelvis.
Conclusions: A shorter than ideal stent, inadequate distal curl and a proximal curl in the upper calix appear to be significant factors in the process of stent migration.