Purpose: To describe the vacuum-assisted mini-percutaneous nephrolithotomy (vmPCNL) technique performed via the 16Ch ClearPetra sheath, to evaluate its outcomes and to analyze intrarenal pressure (IRP) fluctuations during surgery.Methods: Data from all consecutive vmPCNL procedures from September 2017 to October 2019 were prospectively collected. Data included patients’ and stones characteristics, intra and peri-operative items, post-operative complications and stone clearance. Patients undergoing vmPCNL from March to October 2019 were submitted to IRP measurement during surgery.Results: A total of 122 vmPCNL procedures were performed. Median stone volume was 1.92 cm³. Median operative time was 90 min and median lithotripsy and lapaxy time was 28 min. Stone clearance rate was 71.3%. Thirty-one (25.2%) patients experienced post-operative complications, seven of which were Clavien 3. Postoperative fever occurred in nine (7.4%) patients and one (0.8%) needed a transfusion. No sepsis were observed. IRPs were measured in 22 procedures. Mean IRP was 15.3 cmH₂O and median accumulative time with IRP > 40.78 cmH₂O (pyelovenous backflow threshold) was 28.52 sec. Maximum IRP peaks were reached during the surgical steps when aspiration is closed (mainly pyelograms), whereas during lithotripsy and suction-mediated lapaxy, the threshold of 40.78 cmH₂O was overcome in three procedures.Conclusions: vmPCNL is a safe procedure with satisfactory stone clearance rates. Mean IRP was always lower than the threshold of pyelo-venous backflow and the accumulative time with IRP over this limit was short in most of the procedures. During lithotripsy and vacuum-mediated lapaxy, IRP rarely raised over the threshold.

Introduction: Flexible ureterorenoscopy (fURS) is one of the best solutions for treatment of renal calculi <2 cm and for upper urinary tract urothelial carcinoma conservative treatment. An adequate quality of vision is mandatory to help surgeon get better outcomes. No studies have been done, to our knowledge, about what fURS in the market has the best quality of vision. Materials and Methods: Seven different fURS were used to compare the image quality (Lithovue, Olympus V, Olympus V2, Storz Flex XC—in White Light and in Clara+Chroma mode—Wolf Cobra Vision, Olympus P6, and Storx Flex X2). Two standardized grids to evaluate contrast and image definition and three stones of different composition were filmed in four standardized different scenarios. These videos were shown to 103 subjects (51 urologists and 52 nonurologists) who had to evaluate them with a rating scale from 1 (very bad) to 5 (very good). Results: No difference in terms of scores was observed for sex of the participants. Digital (D) ureterorenoscopes were rated better than fiber optics (FOs) ureterorenoscopes. Overall, Flex XC White Light and XC Clara+Chroma image quality resulted steadily better than other fURS (p < 0.0001). Olympus V generally provided a vision better than Lithovue. Cobra Vision and Olympus V2 had superimposable values that were significantly lower than Lithovue's ones. Olympus P6 and Storz X2 offered a low quality of vision compared to the others. In the medium simulating bleeding, Olympus V and V2 significantly improved their scores of 12% and 8.1%, contrary to rest of the ureterorenoscopes. Conclusion: D ureterorenoscopes have a better image quality than FO ones. The only disposable ureterorenoscope tested was comparable to the majority of other D ureterorenoscopes. The best image quality was provided by Storz D ureterorenoscopes, being Clara Chroma the favorite Spies Mode, according to literature.

Purpose: To address the safety and feasibility of adjuvant single-dose upper urinary tract instillation of mitomycin (ASDM) immediately after therapeutic ureteroscopy for upper tract urothelial carcinoma (UTUC) and to compare urothelial (ipsilateral or bladder) recurrence rates in the ASDM group and controls. Materials and Methods: Between April 2015 and August 2018, 52 patients affected by UTUC were treated by endoscopic ablation, of whom 26 were selected for ASDM. Clinical and perioperative data and 30-day complications were recorded. Urothelial recurrence-free survival (URFS) was evaluated with second-look ureteroscopy (URS) and CT scan/URS every 6 months. Results: ASDM was administered through a Single-J (19/25, 76%) or a Double-J (6/25, 24%) in 25/26 (96%) patients. Median follow-up was 18 months (IQR 10–29). The urothelial recurrence rate was 23.5% and 55.5% in the ASDM group and controls, respectively ( p = 0.086). Mean URFS was 28.8 months in the ASDM group vs 18.8 months in controls (log-rank p = 0.067). On multivariate Cox regression, ASDM was associated with a 7.7-fold lower risk of urothelial recurrence (HR = 0.13; 95% CI 0.03–0.65; p = 0.01). Clavien grade ≤II complications occurred in 32% (8/25) and 30.7% (8/26) of the ASDM and control group, respectively ( p = 0.9). Two Clavien III complications occurred in the ASDM group: bladder hematuria after concomitant transurethral resection of bladder and obstructive kidney failure in a single-kidney patient. Conclusions: ASDM was well tolerated after therapeutic URS. It appears to reduce the risk of urothelial recurrence in patients affected by low-grade UTUC without bladder tumor. Therefore, its use should be evaluated.

Purpose: We evaluated if, during lithotripsy, bacteria may be detected in the irrigation fluid of percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS). The concordance between urine culture from stone fragmentation (SFUC), bladder (BUC), renal pelvic (RPUC) and stone (SC) was analyzed. We also assessed the correlation between variables and cultures and their association with systemic inflammatory response syndrome (SIRS) and of a positive SC. Methods: We included 107 patients who underwent PCNL (n = 53) and RIRS (n = 54) from January 2017 to May 2018. Samples for RPUC were obtained by renal catheterization. Stone fragments and irrigation fluid sample were sent for culture. Results: SFUC was positive in 17 (15.9%), BUC in 22 (20.6%), RPUC in 26 (24.3%) and SC in 30 patients (28%). The concordance between SFUC and SC was the highest among all cultures: 94.1%. SFUC and SC grew identical microorganisms in 15/17 (88.2%) patients. Out of 17 (15.9%) patients with SIRS, 8 (7.5%) had sepsis. SFUC had the highest PPV and specificity to detect positive SC and SIRS. Previous urinary tract infection, a preoperative nephrostomy, stone diameter and composition, staghorn calculi, PCNL, positive BUC, RPUC and SFUC were predictors of infected stone. Variables that indicate complex stones, complex PCNL and an infection of the upper tract were associated with SIRS. Conclusion: SFUC is technically feasible, easy to retrieve and to analyze. The spectrum of SFUC potential application in clinical practice is when is not possible to perform a SC, e.g. complete dusting or during micro-PCNL.