Modified technique for difficult ureteral stenting in percutaneous nephrolithotomy via inferior calyx approach

Abstract

Percutaneous nephrolithotomy (PCNL) via single inferior-calyceal tract is suitable for some partial staghorn calculi mainly located in the inferior calyx. A ureteral stent should be inserted at the end of PCNL to avoid urine leakage or ureteral obstruction by residual calculi. However, antegrade ureteral stenting via the inferior calyx is not always successful due to unfavorable lower pole calyx anatomy. In the present study, we introduced a modified method for difficult stenting. First a 0.038-inch zebra guidewire was retrogradely introduced through the previously inserted ureteral catheter and grasped out of the work sheath by a ureteroscopic forceps to develop a through-and-through guidewire; then an 8 Fr guide catheter was inserted antegradely over the guidewire into the ureter after removing the prior ureteral catheter; subsequently the zebra guidewire was removed and antegradely introduced into the bladder through the guide catheter, followed by antegrade insertion of a double J stent. Of 158 patients, 32 needed modified ureteral stenting; and the lower pole infundibulopelvic angle (LPIA) was measured in 25 patients with and in 57 patients without modified stenting. The results showed that LPIA in patients with modified stenting was much smaller than that in patients without modified stenting (56.0 ± 12.58 and 77.4 ± 11.40, P < 0.0001); when the LPIA is <60^°, the modified technique should be recommended. In summary, the modified technique is simple, time-saving, less invasive and highly successful for difficult ureteral stenting in PCNL via inferior calyx.

Key words::

• Ureteral stent
• kidney calculi
• antegrade
• percutaneous nephrolithotomy

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.