To compare the efficacy of ultrasound combined with endoscopy and ultrasound combined with X-ray guided percutaneous nephrolithotomy(PCNL) in the treatment of complex renal calculi.

The clinical data of 119 patients with complex kidney stones treated by ultrasound combined with endoscopy or ultrasound combined with X-ray guided PCNL in the Second Affiliated Hospital of Anhui Medical University from March 2019 to February 2022 were analyzed retrospectively. According to different guidance methods, they were divided into ultrasound combined with endoscopic guidance group and ultrasound combined with X-ray guidance group.There was no significant difference in age [(53.9±14.2) years vs. (55.6±13.5) years], gender (male/female: 38/21 vs. 30/30), body mass index [(25.0±3.7) kg/m² vs. (24.8±3.8)kg/m²], stone location (left/right: 34/25 vs. 31/29), maximum diameter of renal stones [(31.9±8.3)mm vs. (33.9±13.5)mm], kidney stones maximum cross-sectional area [(601.5±242.5)mm² vs. (632.6±278.9)mm²], number of renal calices involved (3.5±0.9 vs. 3.6±1.3), S. T.O.N.E. scores (9.4±1.0 vs. 9.7±1.4), Guy's grade(Ⅲ/Ⅳ: 45/14 vs. 41/19), preoperative hemoglobin [(125.2±21.5)g/L vs. (125.6±18.4)g/L], serum creatinine[(89.1±33.8) μmol/L vs. (81.9±27.1) μmol/L], urinary tract infection (43/59 vs. 47/60)and positive urinary bacterial culture (12/59 vs.11/60) between the two groups(all P>0.05). The patients in the ultrasound combined with endoscopic guidance group were placed in the modified prone split-leg position. Flexible ureteroscope retrograde into the renal pelvis, combined with ultrasound to determine the best puncture calices. The channels were established and stones were removed under the guidance of ultrasound and endoscopy. In the ultrasound combined with X-ray guidance group, the F5 ureteral catheter was placed retrogradely into the operative side ureter under the lithotomy position. Then the patient changed to prone position and the target calices were punctured under the guidance of ultrasound and X-ray. Through anterograde or retrograde injection of contrast medium, the puncture position was determined to enter in the center of the calicean dome, and the channel establishment process and stone removal are monitored. The operative results and postoperative data were recorded.

The average operation time in the ultrasound combined with endoscopic guidance group was significantly shorter than that in the ultrasound combined with X-ray guidance group [(90.2 ± 34.5) min vs. (129.4 ± 43.0) min, P < 0.001]. There was no significant difference in the success rates of initial channel establishment [94.0% (63/67) vs. 87.7% (107/122), P = 0.167], the time of single channel establishment [(7.7 ± 1.9) min vs. (7.7 ± 1.4) min, P =0.765], serum creatinine on the first day after operation[ (89.3±33.6) μmol/L vs. (82.9±27.0) μmol/L, P=0.257] and postoperative hospital stay[(5.3±1.6) d vs.(5.4±1.7) d, P=0.883]. In contrast, patients in ultrasound combined with X-ray guidance group had higher stone free rate [93.3% (56/60) vs. 81.4% (48/59), P=0.049] and lower reoperation rate [3.3% (2/60) vs. 15.3% (9/59), P=0.025]. The mean hemoglobin decrease value of ultrasound combined with endoscopic guidance group was significantly lower than ultrasound combined with X-ray guidance group on the first day after operation [(8.7±6.3) g/L vs. (16.8±6.9) g/L, P<0.001]. The complication rate of ultrasound combined with endoscopic guidance group was significantly lower than that of ultrasound combined with X-ray guidance group [5.1% (3/59) vs. 16.7% (10/60), P = 0.043].

Ultrasound combined with endoscopic guidance PCNL does not need to change body position during operation and has fewer puncture channels, thus saving operation time and reducing complications. It is more suitable for patients with isolated kidney or easy bleeding. Ultrasound combined with X-ray guidance is conducive to the establishment of multi-channel, the stone clearance rate is high and the reoperation rate is low, which is suitable for patients with good health and more renal calices involved with stones.

Kidney calculi; Percutaneous nephrolithotomy; Endoscopic combined intrarenal surgery; X-ray; Efficacy