Comparison of Middle and Lower Calyceal Access for Renal Pelvis Stone in Percutaneous Nephrolithotomy: A Prospective Randomized Study

Abstract

The aim of the study was to evaluate the possible effects of calyceal choice for renal puncture under sonographic guidance on the outcomes of percutaneous nephrolithotomy (PNL). Materials and Methods: A total of 70 patients for whom ultrasound-guided PNL was planned for 20-30-mm single renal pelvic stones were prospectively allocated to group 1 (n:35) with middle calyx entry or group 2 (n:35) with lower calyx entry. Procedure-related parameters such as duration of operation, stone-free rates, complication rates, and radiation exposure time were analyzed in detail. Results: The mean age of the patients was 45.67 ± 1.50 years and the mean stone size was 316.4 ± 17.95 mm 2. There was no significant difference regarding the age, BMI, stone burden, and the grade of hydronephrosis between the groups. Skin to collecting system distance was significantly shorter in the middle calyx entrance (p = 0.021). Total duration of the procedure was again significantly shorter in group 1 cases (74.69 ± 2.94 min) than in group 2 (84.29 ± 4.25 min) (p = 0.003). Regarding the success rates, the postoperative stone-free rate was higher in group 1 (91.4% in group 1, 80.0% in group 2, p = 0.305). Last, there was no statistically significant difference in hemoglobin reduction rates, blood transfusion requirements, and complication rates between the 2 groups. Conclusion: Getting access to the renal pelvis through the middle calyx during ultrasonic guided PNL procedure is more advantageous to lower the calyceal approach by reducing both the duration of the PNL procedure with significantly higher stone-free and comparable complication rates.

Superior calyceal access vs. other calyceal access in percutaneous nephrolithotomy: A systematic review and meta-analysis

“…In addition to facilitating access to the renal pelvis and other calices and achieving a satisfactory stone-free rate with fewer punctures and fewer complications, access through the superior calyx also enables the device to be aligned with the long axis of the kidney in comparison to other access points ( 8 ). Although some studies believed that the middle calyceal access could treat both superior and inferior calyx ( 21 ), the passage through the middle calyx forms a very small acute angle with the superior calyx and inferior calyx. It was often challenging to perform thorough stone cleaning ( 20 ).…”