ABSTRACT
The stone-free rate of 248 cases of CIRF was 32.7% by 1 month, 73.0% by 3 months and 92.7% by 6 months of follow-up. The stone-free rate decreased but not remarkably in accordance with the. increment of the calyceal dilatation (92.9%, 94.9%, 85.7 % and 83.3 % for no, mild, moderate and severe dilatation, respectively, by 6 months of follow-up). The clearance of the CIRF was not influenced by the location of CIRF, the pelviocalyceal angle, the infundibular length and number of the lower calices. Of 16 patients who had residual stone fragments by 6 months and underwent an additional session of ESWL, 12 became stone-free by another 6 months of follow-up. Therefore, it is desirable to wait for clearance of CIRF for at least 6 months before offering further treatment regardless of CIRF location and anatomical variation of the calices containing CIRF. Repeated ESWL even for stone fragments of 3-tmm in diameter found initially 1 month after the last session or ESWL might promote clearance of the CIRF, and additional ESWL for persistent CIRF could be an appropriate adjunctive measure.