Objective: We aimed to determine the individualized management of middle-sized kidney stones in the lower pole calyces that can be removed using shock wave lithotripsy (SWL) (Group A), flexible ureteroscopic retrograde intrarenal surgery (RIRS) (Group B) and micro-percutaneous lithotomy (micro-PNL) (Group C).

Materials and Methods: Patients who had 1-2 cm kidney stones in the lower pole calyces whose calyceal necks (length: <10 cm, and width: > 5mm), pelvicalyceal angle (>30o) and relatively shorter stone-skin distance as determined based on tomographic urography results were included in the study. Patients with renal cystine, whewellite stones or stones with a hardness above 1000 Hounsfield units were excluded. The groups were not formed randomly. Contarily, treatment methods were explained to the patients and let them decide the treatment method for themselves. Each group consisted of 34 patients.

Results: After excluding nine patients who were lost to follow-up, the study was completed with 93 patients at the final analysis. Stone-free rate was lower in Group A (47%) than Groups B (80.5%) and C (77%) (p<0.001). The mean number of sessions was 2.1 for Group A, 1.55 for Group B and 1 for Group C (p<0.001). Average procedure costs were $169, $1427, and $947 for Groups A, B, and C, respectively (p<0.001). Median length of hospital stay for Groups A, B, and C was 1, 20, and 48 hours (p<0.001), respectively, and 2, 3.9 and 5.5 working days were lost, respectively (p<0.001).

Conclusion: RIRS and micro-PNL had more stone-free rate, but number of working days were lost with lower medical expenditures in the SWL group. The priority of the patients should be determined, and the choice of treatment should be decided in collaboration with them.

Keywords : lower calyx, middle sized kidney stone, shock wave lithotripsy, retrograde intrarenal surgery, micro-percutaneous nephrolithotomy, cost-efficiency