The clinical safety and efficacy of upper pole access percutaneous nephrolithotomy (uPPCNL) for inferior pole stones

ABSTRACT

@#<p style="text-align justify;"><strong>OBJECTIVE:</strong> Traditionally, percutaneous nephrolithotomy (PCNL) for a lower pole stones are directly removed through an inferior polar access. The authors preferentially treated inferior pole calculi with an upper polar access and evaluated the clinical outcomes.<br /><strong>METHODS:</strong> Between January 2010 and April 2016, 32 patients with inferior calyceal stones were treated uPPCNL. All stones were diagnosed using an unenhanced CT scan. The efficacy (stone-free rate) was determined by comparing the preoperative and postoperative imaging. Clinical safety was assessed based on intraoperative parameters pertaining to operative time, blood loss, urinary extravasation, calyceal injury, pelvic perforation and other untoward events. These complications were summarized using the Clavien-Dindo grading system.<br /><strong>RESULTS:</strong> The male to female ratio is 1.11. All stones included in the study were pure inferior calyceal in location. The average stone size was 1.65±0.84cm (Range0.6-4.4) with a mean durility of 936±298HU (Range 350-1500). Stone-free rate was 96.8% (31/32) after a single session of PCNL. The mean operative time was 97±43 minutes (Range40-230). According to the Clavien-Dindo classification, 26(81.3%) had no complication, 5 (15.6%) had Grade 1 (fever), and 1 (3.1%) had Grade 2.<br /><strong>CONCLUSION:</strong> uPPCNL is effective and safe for patients with inferior calyceal stones and confers the following advantages 1) shorter skin-to-calyceal distance 2) straight line to the UPJ and inferior pole 3) a panoramic view of the collecting system 4) less stone migration 5) minimal torque of the nephroscope. This minimally invasive procedure achieves a high stone clearance rate with acceptably low complication rates.</p>