To compare the outcomes of transperitoneal and retroperitoneal laparoscopic pyelolithotomy procedures.

A total of 104 consecutive laparoscopic pyelolithotomy surgeries performed by a single surgeon on patients with staghorn or renal pelvic calculi larger than 20 mm were evaluated. Intraoperative and postoperative clinical parameters from two groups, transperitoneal (TLPL) (N = 55) and retroperitoneal (RLPL) (N = 49), were compared. The surgeon performed TLPL for the first five years and then switched to the RLPL approach for the next five years.

There were no significant differences in general demographic variables and stone size (26.55 vs. 24.73 mm, P = 0.8). Operation time and change in serum creatinine levels did not significantly differ between the two approaches. However, patients who underwent TLPL had longer hospital stays than RLPL (3.23 ± 1.21 vs. 2.36 ± 1.10 days, P = 0.0001). Additionally, TLPL was associated with a greater drop in hemoglobin levels (1.53 ± 1.04 vs. 1.17 ± 0.68, P = 0.04), higher rates of postoperative fever (12.7% vs. 0.0%, P = 0.01).

The retroperitoneal approach in laparoscopic pyelolithotomy for large renal pelvic stones resulted in fewer postoperative fevers, reduced hemoglobin drops, and shorter hospital stays than the transperitoneal approach. However, the stone-free rates were similar for both groups.