Non papillary mini-percutaneous nephrolithotomy: early experience.

PURPOSE: This study aims to evaluate the non-papillary puncture for mini-PCNL in terms of safety and efficacy. METHODS: A total number of 32 patients were subjected to mini-PCNL by the performance of non-papillary punctures over 6 months. One-step track dilation to 22 Fr took place in all cases. An 18 Fr nephroscope (Slender, Karl Storz GmbH, Germany) and an ultrasound lithotripter (Lithoclast Master, EMS S.A, Switzerland) with 9.9 Fr probe was used. Demographics and perioperative data are prospectively collected from an institutional board-approved database and the presented data were retrospectively collected. RESULTS: The average cumulative stone size was 23.53 ± 6.6 mm. Mean operative time was 44.6 ± 13.44 min and primary stone-free rate after PCNL was 96% and 85.7% for single and multiple access, respectively. Second access was performed in seven cases, all of which had multiple stones. Mean hemoglobin drop was 1.23 ± 0.88 gr/dL. The patients stayed 2.56 ± 0.98 days in the hospital. Overall complication rate was 9.37%, without encountering any severe bleeding complication. CONCLUSION: Using non-papillary access for mini-PCNL did not result in significant blood loss and need for transfusions. The respective data were directly comparable to contemporary literature and the safety of mini-PCNL by a non-papillary approach could be advocated.

Optical coherence tomography provides images similar to histology and allows the performance of extensive measurements of drug-eluting metal stents in animal ureters.

Optical coherence tomography (OCT) images and histology images of metal stents (MSs) inserted in animal ureters were compared, and the reliability of an OCT-based automated method for the performance of quantitative evaluation of ureteral MSs was evaluated. A zotarolimus-eluting metal stent (ZES) and a bare metal stent (BMS) were inserted in each ureter of ten pigs and six rabbits. OCT was performed in unobstructed stented ureters. Histopathologic examination of the stented ureters embedded in glycol-methacrylate took place. Quadrants of OCT images were compared to their respective histologic images by employing two independent observers who delineated different layers in the quadrants of OCT images and correlated them to the respective histologic quadrants. Manual (integrated OCT device software) and automated measurements of the OCT images using an automated strut detection method were compared. The observers highly agreed on the delineation of urothelium from the lamina propria and the lamina propria from the muscle layer of the ureteral wall. The algorithm measurements were similar to the manual measurements, and the algorithm proved to be reliable in the evaluation of ureteral MSs. Significantly higher endothelial hyperplasia of the BMSs in comparison to the ZESs was also quantitatively demonstrated by the strut detection method. OCT proved to be a reliable method for the evaluation of ureteral MSs. OCT provided images of the stented ureteral lumen similar to light microscopy quality. Measurements of the stented ureter are reliably performed by the automated strut detection method.