Description of a novel method for renal puncture in supine percutaneous nephrolithotomy and comparison with a previously described method

Renal Access in Pediatric Supine Miniaturized Percutaneous Nephrolithotomy: Comparative Evaluation of Ultrasound-Fluoroscopy Combined and Biplanar (0°-90°) Fluoroscopic Techniques

Introduction: Ultrasound (US)-guided puncture has the benefits of avoiding radiation and limiting the risk of visceral injury. We aimed to evaluate the results of two different renal access techniques during pediatric supine mini percutaneous nephrolithotomy (smPCNL) in a comparative manner. Patients and Methods: Data obtained from pediatric patients undergoing smPCNL by single surgeon between September 2021 and 2023 were reviewed retrospectively. Children were divided into two groups namely; biplanar 0°-90° fluoroscopy (Group-F) and US-fluoroscopy combined (Group-C). In all cases, preoperative, operative, and postoperative findings were recorded. Success was defined as the determination of either no (complete stone-free status) or < 4 mm residual fragments (CIRF) on US and X-ray (postoperative 3rd month) images. Complications were evaluated according to modified Clavien-Dindo classification. Results: Data of 54 patients with a mean age of 8.6 years (Group-F = 30, Group-C = 24) are reviewed. In addition to the similar success rates in both groups (Group-F = 86.7% Group-C = 87.5% p = 0.928), similar minor complications were noted in the majority of the cases. No child required transfusion and/or angioembolization. Although the fluoroscopy and operation time were lower in Group-C, the difference was not statistically significant. Conclusion: US-fluoroscopy combined access technique can be applied with similar success and complication rates in pediatric smPCNL. Ultimately, as experience is gained, this technique may lower radiation exposure, although this was not observed in the current study.

Is it necessary to have a guidewire down through the ureter during mini percutaneous nephrolithotomy? Single-centre experience with 1052 cases

OBJECTIVES

In this study, it is aimed to identify the rate of successful placement of a guidewire down through the ureter during PNL and to compare the outcomes of different locations of guidewires in the collecting system following renal puncture in terms of success and complications rates.

PATIENTS AND METHODS

Data of 1052 patients who underwent miniPNL in our institution between January 2014 and November 2020 were analysed. Patients were divided into three groups. Group I consisted of patients with the guidewire coiled within the punctured calyx, group II consisted of patients with the guidewire reaching the renal pelvis and group III consisted of patients with the guidewire passed down through the ureter. The groups were compared for successful tract creation and complication rates.

RESULTS

There were 303 (28.8%) patients in group I, 330 (31.4%) patients in group II and 419 (39.8%) patients in group III. Successful tract dilation at the first attempt was established in 298 (94.7%) patients in group I, 328 (99.4%) patients in group II and in all of the 419 (100%) patients in group III. Successful tract creation was established in a second attempt in all of the patients failed in the first attempt. The groups were similar for stone-free and complication rates.

CONCLUSIONS

Placement of guidewire down through the ureter could not be established in more than 60% of the cases. Location of guidewire prior to dilation did not affect the outcomes. Therefore, we suggest to proceed with tract creation even when the guidewire coils within the punctured calyx.