Retroperitoneal vs transperitoneal laparoscopic lithotripsy of 20-40 mm renal stones within horseshoe kidneys

Table 2 Intergroup comparisons of postoperative estimated glomerular filtration rate change relative to preoperative levels

eGFR [mL/(min·1.73 m2)]	Retroperitoneal group (n = 7)	Transperitoneal group (n = 5)	P value
Postoperative day 1	-3.86 ± 0.69	-2.20 ± 2.17	0.176
Postoperative day 30	-3.29 ± 1.11	-2.40 ± 2.07	0.581

Values are expressed as mean ± SD. P values were calculated for intergroup comparisons using the Wilcoxon signed-rank test. eGFR: Estimated glomerular filtration rate.