Minimal invasive treatment of urethral strictures: An experimental study of the effect of paclitaxel coated balloons in the wall of strictured rabbit's urethra.

PURPOSE: The aim of this study is the evaluation of the distribution of paclitaxel (PTX) released by a coated balloon in the layers of rabbit's urethra. METHODS: 18 rabbits were included. A laser device was used for the stricture formation. After two weeks, dilation of the strictured urethra was performed by using Advance 35LP PTA balloons and Advance 18 PTX PTA balloons. The experimental models were divided into 3 groups. The group Α included two rabbits without any intervention except for the stenosis procedure. Group B compromised six rabbits that underwent dilation with Advance 35LP PTA balloons. Group C consisted of 10 rabbits to which dilation with both Advance 35LP PTA balloons and Advance 18 PTX PTA balloons was applied. Histological evaluation and Immunohistochemistry were performed on all specimens. RESULTS: Inflammation, fibrosis and ruptures were detected in the specimens of the study. In specimens of Group C the decrease of inflammation and fibrosis rate was greater. Anti-PTX antibody was detected in the epithelium, lamina propria and smooth muscle layer of all specimens of urethras that have been harvested immediately and 1 day after the dilation with Advance 18 PTX PTA balloon and it was not observed in any layer of the urethral wall of the rest of the examined specimens of Group C. CONCLUSIONS: PTX's enrichment was detected in the smooth muscle layer of all specimens that have been harvested immediately and 24h after the dilation with Advance 18 PTX PTA balloons. PTX may play an inhibitive role in the recurrence of the stenosis.

Percutaneous antegrade management of large proximal ureteral stones using non-papillary puncture.

Objective: To evaluate the feasibility and the safety of medial non-papillary percutaneous nephrolithotomy (npPCNL) for the management of large proximal ureteral stones. Methods: We evaluated prospectively collected data of 37 patients with large proximal ureteral stones more than 1.5 cm in diameter treated by prone npPCNL. Depending on stone size, in-toto stone removal or lithotripsy using the Lithoclast® Trilogy (EMS Medical, Nyon, Switzerland) was performed. Perioperative parameters including operative time (from start of puncture to the skin suturing), stone extraction time (from the first insertion of the nephroscope to the extraction of all stone fragments), and the stone-free rate were evaluated. Results: Twenty-one males and 16 females underwent npPCNL for the management of large upper ureteral calculi. The median age and stone size of treated patients were 58 (interquartile range [IQR]: 51-69) years and 19.3 (IQR: 18.0-22.0) mm, respectively. The median operative time and stone extraction time were 25 (IQR: 21-29) min and 8 (IQR: 7-10) min, respectively. One case (2.7%) of postoperative bleeding and two cases (5.4%) of prolonged fever were managed conservatively. The stone-free rate at a 1-month follow-up was 94.6%. Conclusion: The npPCNL provides a straight route to the ureteropelvic junction and proximal ureter. Approaching from a dilated portion of the ureter under low irrigation pressure with larger diameter instruments results in effective and safe stone extraction within a few minutes.

Use of artificial stones in training and laboratory studies, have we found the right material? Outcomes of a systematic review from the European School of Urology.

Objective: In this review, we investigated the current literature to find out which artificial stones (AS) are available in endourology, and in which experimental and training schemes they are used. Materials and Methods: A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Twenty-one out of 346 studies met our inclusion criteria and are presented in the current review. The inclusion criteria were the existence of AS and their use for laboratory and training studies. Results: There is a wide variety of materials used for the creation of AS. BegoStone powder (BEGO USA, Lincoln, Rhode Island) and plaster of Paris™ were used in most of the studies. In addition, Ultracal-30 (U. S. Gypsum, Chicago, IL) was also used. Other materials that were used as phantoms were AS created from plaster (Limbs and Things, UK), standardized artificial polygonal stone material (Chaton 1028, PP13, Jet 280; Swarovski), model stones consisting of spheres of activated aluminum (BASF SE, Ludwigshafen am Rhein, Deutschland), Orthoprint (Zhermack, Badia Polesine, Italy), and a combination of plaster of Paris, Portland cement, and Velmix (calcium sulfate powder). Many experimental settings have been conducted with the use of AS. Our research demonstrated nine studies regarding testing and comparison of holmium: yttrium-aluminum-garnet laser devices, techniques, and settings. Six studies were about extracorporeal shock wave lithotripsy testing and settings. Three experiments looked into treatment with percutaneous nephrolithotomy. Additionally, one study each investigated imaging perioperatively for endourological interventions, stone bacterial burden, and obstructive uropathy. Conclusion: AS have been used in a plethora of laboratory experimental studies. Independent of their similarity to real urinary tract stones, they present a tremendous potential for testing and training for endourological interventions.

How long do we need to reach sufficient expertise with the avatera® robotic system?

PURPOSE: To investigate the learning curve in four basic surgical skills in laparoscopic and robotic surgeries, and evaluate the approximate time needed to reach sufficient expertise in performing these tasks with the avatera® system. METHODS: Twenty urology residents with no previous experience in dry-lab and robotic surgery were asked to complete four basic laparoscopic tasks (peg transfer, circle cutting, needle guidance, and suturing) laparoscopically and robotically. All participants were asked to complete the tasks first after watching the Uroweb educational material and, second, after undertaking a 2-hour training in robotic and laparoscopic dry-lab. Thereafter, all trainees continued to undertake 2-hour training programs until being able to complete the tasks with the avatera® robot at the desired time. Paired t test and one-way ANOVA test were used to analyze time differences between the groups. RESULTS: Time needed to complete all tasks either robotically or laparoscopically was significantly less in the second compared to the first attempt for all Groups in each Task. In the robotic dry-lab, time needed to complete the tasks was significantly less than in the laparoscopic dry-lab. A significant effect of previous laparoscopic experience of the participants on the training time needed to achieve most of the goal times was detected. CONCLUSION: The results of the study highlight the role of previous laparoscopic experience in the training time needed to achieve the performance time goals and demonstrate that the learning curve of basic surgical skills using the avatera® system is steeper than the laparoscopic one.

Grafts in Peyronie's surgery without the use of prostheses: a systematic review and meta-analysis.

ABSTRACT: Peyronie's disease (PD) is characterized by abnormal penile curvature, and various surgical methods have been developed using different graft materials. However, there is currently no universal agreement on which type of graft is the best. The objective of this review was to evaluate the available literature and identify the most effective graft material for penile curvature correction in PD. A literature search was conducted using electronic databases, including PubMed, Scopus, and the Cochrane Library. The patients, intervention, comparison, and outcome (PICO) approach was used to define the eligibility of studies. Two authors independently selected studies, evaluated them, and extracted data. Random-effect models using the DerSimonian-Laird method were used. Most studies were single-arm studies and had a high risk of bias. Buccal mucosa grafts (BMG) were found to result in the highest penile straightening rates and were associated with the least de novo erectile dysfunction. TachoSil grafts demonstrated a high success rate in straightening despite a higher mean preoperative curvature, while Tutoplast grafts had a higher incidence of postoperative erectile dysfunction. BMG had the highest percentage of postoperative penile straightening. Overall, the TachoSil graft showed the best performance when preoperative curvature is taken into account. Based on the available literature, BMG appear to be the most effective for penile curvature correction in PD, but this is offset by the requirement for low preoperative curvature. The TachoSil graft shows the best overall performance when preoperative curvature is considered. Comparative randomized clinical trials are still needed to determine graft superiority.

Location of ureteral access sheath in the ureter. Does it affect the fluid flow in different calyces?

Introduction: The aim of this study was to evaluate outflow variation in different locations of the pyelocaliceal system with the use of different ureteral access sheath (UAS) sizes and different UAS positioning. Material and methods: The experimental setup included an anaesthetised porcine model, a 7.5-Fr ureteroscope with a 200-µm laser fibre inserted in the working channel, a hand-held pumping irrigating system, and UAS of different sizes, namely: 9.5/11.5 Fr, 12/14 Fr, and 14/16 Fr. Each UAS was placed just below the ureteropelvic junction (UPJ) or in the mid-ureter. The ureteroscope was placed in the renal pelvis, upper and lower calyces, and outflow measurements were obtained with 3-second interval pumping for one minute in every experimental setup. Results: The UAS positioning in the mid-ureter was associated with significantly higher outflow rates in the lower calyx (p = 0.041). While the UAS was below the UPJ, we observed a trend of lower outflow rate in the lower calyx, which was completely inverted when the UAS was in the mid-ureter. Increasing the UAS size from 9.5/11.5 Fr to 12/14 Fr led to a significant increase in outflow in the renal pelvis and upper calyx (p = 0.007), but not in the lower calyx. A further increase to 14/16 Fr did not produce increased flow. Conclusions: Different locations of the pyelocaliceal system have different fluid mechanics during fURS. In the renal pelvis and upper calyx increasing the diameter of the UAS improved the outflow, whereas in the lower calyx the position of the UAS seems to be the most relevant factor. These variables should be considered when performing fURS, especially with high-power laser lithotripsy.

How Safe Are the Laparoscopic and Robotic Graspers? Evaluation of the Novel Avatera Robotic Surgical System: An Acute In Vivo Study on a Porcine Model.

OBJECTIVE: To evaluate the tissue injury caused by the force applied by the roboticassisted graspers of avatera robotic surgical system on bowel tissue. METHODS: An experimental in vivo porcine model with 1 pig was conducted. After a standard transperitoneal setup of the avatera robotic surgical system, different laparoscopic and robotic graspers were used on the bowel with maximum force applied each time. Robotic atraumatic grasper, laparoscopic right angle grasper, laparoscopic curved grasper, and laparoscopic atraumatic grasper were used. After using all graspers, the pig was sacrificed. The bowel segments were resected and sent for histological analysis. RESULTS: The pathologist reported that all the graspers caused signs of acute inflammation without any irreversible damage or signs compatible with ischemia of the tissue. No significant difference in histology was observed between the graspers. CONCLUSION: No permanent damage was caused by graspers, except for acute, reversible inflammation. Concluding, the avatera grasper could be safe to use on bowel segments, independent of the applied pressure.

Bladder Cancer during Pregnancy: A Review of the Literature.

Bladder malignancy represents the fourth most common cancer in men and the eighth in women in the western world. Women under 75 years of age have a risk of 0.5-1% of developing bladder cancer. The diagnosis usually occurs between 65 and 70 years of age, whereas the mortality rate for women varies from 0.5 to 4 per 100,000 every year. Nulliparous women present a greater risk than women who have given birth. The risk is further decreased when parity increases. Theoretically, hormonal changes occurring during pregnancy play a protective role. Smoking and occupational exposure to specific chemicals are the most common risk factors of bladder cancer. Other risk factors such as chronic urinary tract inflammation, cyclophosphamide, radiotherapy, and familial correlation have been reported. The aim of this review is to highlight a rare combination, which is the co-existence of bladder malignancy and pregnancy. We present thirteen different cases of women who were diagnosed with malignant bladder tumors during their pregnancy. A review of the literature was conducted, focusing on the unspecific symptoms, possible diagnostic tools, and suitable treatment modalities. The management of bladder cancer in pregnancy is a challenging process. The fragile balance between the possible complications of pregnancy and maternal health is yet to be discussed.

Outcomes of thulium prostatectomy with "Oyster technique" versus transurethral prostatectomy (TURP): a randomized control trial.

PURPOSE: To compare the perioperative and postoperative outcomes between Oyster prostate vaporesection using Tm-YAG laser and the conventional transurethral prostatectomy using monopolar energy. METHODS: Patients with LUTS with an accumulative size of at least 60 ml were randomly assigned to one of two parallel groups to undergo Tm-YAG laser vaporesection (Group 1) or conventional monopolar transurethral prostatectomy (Group 2). The primary endpoints were the reduction in IPSS and the increase in Qmax postoperatively. Secondary endpoints included the Hemoglobin drop, the complication rate, the changes in urodynamic parameters, the duration of hospitalization and catheterization and the changes in IIEF during the 24-month follow-up. RESULTS: In total 32 and 30 patients were enrolled in Groups 1 and 2, respectively. Patient age (p = 0.422) and prostate volume were similar among the groups (p = 0.51). The outcomes in terms of IPSS decrease and Qmax amelioration were comparable (p = 0.449 and p = 0.237, respectively). Operative and hospitalization times were lower in Group 1 (p = 0.002 and p = 0.004, respectively). Hemoglobin drop, changes in urodynamic parameters and improvement in IIEF and QoL scores did not differ among the two Groups. The average time with the catheter was 2.06 ± 0.35 and 2.5 ± 0.82 (p = 0.003) days for Group 1 and Group 2, respectively. The overall complication rate was 6.2% for Group 1 and 13.3% for Group 2. CONCLUSIONS: The Oyster technique leads to similar postoperative outcomes compared to the standard monopolar transurethral prostatectomy. The shorter catheterization, hospitalization and operation time should be considered advantages of the Oyster technique.

The effect of percutaneous tract dilation technique on renal parenchymal trauma: An experimental in vivo study on a porcine model.

Purpose: The purpose of this study was to evaluate renal parenchymal trauma of two-step dilation compared to the conventional Amplatz gradual dilation during percutaneous nephrolithotomy on a porcine model. Materials and Methods: A nonpapillary percutaneous access tract was established under fluoroscopic guidance in both kidneys of four female pigs. On the right kidney of each pig, gradual dilation was performed using an Amplatz dilator set with a gradual dilation to 30 Fr, whereas on the left, a two-step dilation was utilized using only 16 Fr and 30 Fr dilators. Two of the animals were euthanized immediately after the procedure and the remaining two 1 month later. The pigs that were kept alive underwent a contrast-enhanced computed tomography immediately, 15, and 30 days postoperatively. A dimercaptosuccinic acid (DMSA) scintigraphy and single-photon emission computed tomography-computed tomography (CT) were also performed after the last CT and afterward, the pigs were sacrificed. All kidneys were harvested for pathohistological examination. Results: The follow-up radiologic imaging showed similar parenchymal damage caused by the compared dilation techniques and an expected reduction in scar size in the later scans. No scar was identified by DMSA in any kidney. Gross and microscopic examinations conducted both on the kidneys that were harvested immediately after the procedure and the ones from the animals that were left to heal, revealed no significant differences in tissue damage, grade of fibrosis, or inflammation depending on the dilation method. Conclusions: Our study showed no inferior outcomes caused by two-step dilation compared to gradual dilation regarding renal parenchymal damage following a nonpapillary puncture. In fact, postoperative imaging findings suggested a trend toward better healing and less scar tissue when the two-step method was used.

Holmium: Yttrium-aluminum-garnet laser lithotripsy: Is there a difference in ablation rates between short and long pulse duration?

Introduction: The high-power holmium: yttrium-aluminum-garnet lasers provide a wide variety of settings for stone disintegration. The aim of this in vitro study is to evaluate the effect of short and long pulse duration on ablation rates on urinary stones. Materials and Methods: Two types of artificial stones were created by BegoStone™ with different compositions (15:3 and 15:6, stone/water ratio). Stones with a 15:3 and 15:6 powder-to-water ratio were defined as hard and soft stones, respectively. Lithotripsy was performed with different laser settings using a custom-made in vitro model consisting of a 60 cm long and 19 mm diameter tube. The ablation rate is defined as the final total mass subtracted from the initial total mass and divided to the time of treatment. Stone ablation rates were measured according to different laser settings with total power of 10W (0,5J-20 Hz, 1J-10 Hz, 2J-5 Hz) and 60W (1J-60 Hz, 1,5J-40 Hz, 2J-30 Hz). Results: Higher pulse rates and higher total power settings were related to higher ablation rates. Short pulse duration was more effective on soft stones, whereas long pulse duration was more effective on hard stones. For the same power settings, the highest energy-lowest frequency combination resulted in higher ablation rate in comparison to the lowest energy-higher frequency combination. Finally, short and long pulse average ablation rates do not differ so much. Conclusion: Regardless of the stone type and pulse duration, utilization of higher power settings with higher energies increased the ablation rates. Higher ablation rates were demonstrated for hard stones using long pulse duration, and for soft stones with short pulse duration.

High-power laser lithotripsy - do we treat or harm? Histological evaluation of temperature effects in an in vivo study with thulium fiber laser.

Introduction: The aim of this study was to evaluate the possible histopathological alterations that occur in the kidneys due to a continuous temperature increase above 43°C for one hour of lithotripsy using a newly introduced thulium fiber laser (TFL). Material and methods: Two female pigs were used. After the insertion of a 9.5/11.5 ureteral access sheath, flexible ureteroscopy and laser lithotripsy for one hour were conducted. A TFL laser with a 200-µm fiber was used. The power setting used was 8 W (0.5 J × 16 Hz). A K-type thermocouple was inserted and fixed in the upper calyx of the right porcine kidney to record the temperature in the pelvicalyceal system during the laser activation. Second-look flexible nephroscopy followed by nephrectomy and pathohistological evaluation of the operated kidney was performed one week after the procedure in the first pig and 2 weeks after the surgery in the second pig. Results: Flexible nephroscopy did not reveal significant differences between the 2 porcine kidneys. Nevertheless, the histopathological report demonstrated severe alterations in the kidney of the first pig. Mild changes were reported in the kidney of the second pig. A significant improvement in inflammation and haemorrhagic lesions was demonstrated when comparing the 2 kidneys. Conclusions: The difference demonstrated between the 2 kidneys based on the histopathological report shows that the healing process is capable of improving severe to mild alterations within a one-week time frame. Two weeks after the surgery, only minor changes were observed, suggesting that even temperature increases above the threshold can be tolerated regarding renal damage.

Non-papillary prone percutaneous nephrolithotomy for renal abnormalities: single-institution experience.

PURPOSE: To evaluate the effectiveness and safety of non-papillary prone PCNL for the treatment of patients with renal abnormalities. METHODS: An observational retrospective cohort study including PCNL cases of patients with renal abnormalities was performed. The following inclusion criteria were applied: renal stones > 1.5 cm with maximal diameter, anatomical malformations of affected kidney (malrotated kidneys, horseshoe kidneys and kidneys with complete duplicated systems, medullary sponge kidney), patients treated with standard (30Fr) PCNL or mini-PCNL (22Fr). The lithotripsy was performed using the Lithoclast Master or the Lithoclast® Trilogy (EMS Medical, Nyon, Switzerland). RESULTS: Overall, 57 patients, 35 males, and 22 females with any renal malformation underwent non-papillary prone PCNL. Our study included 25 patients with horseshoe kidneys, 21 with malrotated kidneys, 9 with kidneys with duplicated pelvicalyceal systems and 2 with medullary sponge kidneys. The mean cumulative stone size was 36 ± 1.4 mm and most of the stones were in the lower calyceal group (36.9%) and in the pelvis (27.2%). The stone-free rate (SFR) was 84.2% and the mean hospitalization time was 2.7 ± 0.7 days. In total, postoperative complications were developed in six patients (10.5%), half of them presenting fever and the other half requiring blood transfusion (Grade II). CONCLUSION: The PCNL is the method of choice for treating large stones in anomalous kidneys. The generally accepted panacea that only a papillary puncture is safe is questioned by our results. Based on our experience, a non-papillary puncture proved to be a safe and effective procedure.

Robot-Assisted Radical Nephrectomy Using the Novel Avatera Robotic Surgical System: A Feasibility Study in a Porcine Model.

Purpose: To evaluate the feasibility and intraoperative technical parameters of the new robot-assisted surgical system Avatera by performing bilateral nephrectomy in a live porcine model. Materials and Methods: Six pigs underwent bilateral robot-assisted radical nephrectomy using the Avatera robotic system (RS). The operations were performed by experienced open (Group 1) and laparoscopic (Group 2) surgeons. The operating time, docking time, set-up time, and console time were evaluated. Data regarding intraoperative complications (major or not), injury of adjacent organs, and technical difficulties during the operation were also recorded. Results: Robot-assisted bilateral nephrectomy was completed effectively in all sample pigs. The docking time and set-up time were similar among the two groups, whereas the console time and operating time were significantly longer for the open surgeon group. Two intraoperative minor complications occurred in the open surgeon's group. An inadvertent damage of the renal vein occurred in two cases and the bleeding was controlled effectively. Other than the initial two cases, the estimated blood loss was <50 mL in both groups. Injury of the adjacent organs was not noticed. Conclusions: The study demonstrated that radical nephrectomy using the Avatera robotic surgical system is technically feasible, safe, and valid in pigs. Our results warrant the application of the Avatera RS in other urologic procedures, collecting data for further clinical trials.

The feasibility of robot-assisted radical cystectomy: an experimental study.

PURPOSE: To investigate the feasibility of the avatera system for performing robot-assisted radical cystectomy (RARC) followed by intracorporeal reconstruction of ileal neobladder. METHODS: Six anesthetized female pigs were used to perform RARC and formation of the intracorporeal orthotopic ileal neobladder. Three surgeons with different level of expertise in the use of robotic systems performed RARC after a short instructional lecture and a 2-h hands-on training. The urinary diversion phase was performed only by the experienced surgeon. The successful completion of the procedure, operative time for demolitive and reconstructive phases, intraoperative blood loss and malfunction of the robotic system were evaluated. RESULTS: An improvement of the operative time was observed for each surgeon. The experienced surgeon, the fellow and the resident improved their time by 11, 15, and 22 min, respectively, between the first and the second RARC performed. The most significant time difference was demonstrated by the resident, who had no previous experience in using robotic systems. The time difference between the first and the last orthotopic ileal neobladder creation for the experienced surgeon was 51 min. CONCLUSION: The feasibility of avatera system for performing complex surgical procedure such as RARC with intracorporeal neobladder formation was demonstrated by this experimental study. No major bleeding or severe malfunctions were observed during the procedures. Significant improvement in operative time was demonstrated with the increasing experience from 1st to 6th case.

Clearance of Metal Particles After Percutaneous Nephrolithotomy with Trilogy Lithotripter.

Purpose: To evaluate the clearance of metal particles produced and released in the pelvicaliceal system (PCS) during percutaneous nephrolithotomy (PCNL) with the use of the Swiss Lithoclast® Trilogy dual-energy (EMS Urology, Nyon, Switzerland) lithotripter. Methods: An experimental in vivo study and a clinical investigation of case series were conducted. An in vivo porcine model with two pigs for lithotripsy (after inserting artificial stones into the collecting system) and two pigs for submucosal injection of metal particles (provided by the manufacturer of Trilogy) was conducted. Porcine kidney histology analysis for metal leftovers was conducted immediately or 2 weeks after the surgery. A prospective observational study design included 10 consecutive patients treated with conventional 30F PCNL or with 22F mini-PCNL technique. Only the patients with the confirmed metal particles in the PCS during the initial PCNL and the need for additional retrograde intrarenal surgery over a period of 2-4 weeks were selected. The presence of metal particles was evaluated during the second endoscopic surgery. Results: The generated metal particles during PCNL and the submucosally injected particles were not found macroscopically 2 weeks postoperatively in porcine models. No pathologic changes such as foreign body granuloma or inflammation were found. Similarly, no metal particles were observed during the second look endoscopy (n = 10). Conclusion: Metal particles observed endoscopically using the Trilogy lithotripter are cleared with no pathologic evidence of tissue damage from the metal particles 2 weeks after the procedure. Thus, the intraoperative release of any particle by the Trilogy lithotripter should not raise any safety concerns.

Non-Papillary Access for the Percutaneous Antegrade Treatment of Renal and Ureteral Stones.

OBJECTIVE: To evaluate the feasibility and success of medial non-papillary percutaneous access for the antegrade treatment of different locations of ureteral stones, with and without concomitant renal stones. METHODS: We performed an analysis of prospectively collected data of 72 patients, being subjected to percutaneous antegrade ureterolithotripsy. Stones located anywhere in the ureter with or without concomitant renal stones were included. A 12Fr, 22Fr, or 30Fr percutaneous tract dilation was performed based on the size of the stone pelvicalyceal system. Perioperative and demographic parameters were gathered and evaluated. The Lithoclast Trilogy (EMS Medical, Nyon, Switzerland) High-power holmium laser devices Cyber Ho 150 (Quanta System, Samarate, Italy) or MOSES Pulse 120H (Lumenis Ltd, Yokneam, Israel) were used for lithotripsy. RESULTS: The average age and cumulative stone size of the patients were 57.9 ± 27.1 years and 24.2 ± 5.4 mm, respectively. The mean manipulation time was 36.9 ± 14.8 minutes. The mean hospitalization time was 2.5 ± 0.5 days and the average hemoglobin loss was 1.02 ± 0.18 gr/dL. The stone-free rate after percutaneous antegrade ureterolithotripsy was 95.8 % (69 patients), while the overall complications rate was 5.6 %, with 3 cases of fever and one case of prolonged hematuria that were treated conservatively. CONCLUSION: Non-papillary percutaneous antegrade ureterolithotripsy is a safe and reliable technique for the treatment of patients with ureteral stones, with or without the co-existence of renal stones. A high stone-free rate of 95.8% was reported at 1-month after the surgery carrying a weighted risk of developing postoperative complications.

Nonpapillary prone endoscopic combined intrarenal surgery: effectiveness, safety and tips, and tricks.

PURPOSE: To evaluate the effectiveness and safety of nonpapillary prone endoscopic combined intrarenal surgery (ECIRS) and provide practical tips and tricks for the successful accomplishment of the procedure respecting the anatomical particularities. MATERIAL AND METHODS: This study is an analysis of a prospectively collected database including all cases of ECIRS performed between January 2019 and December 2021 in a high-volume tertiary center. All patients underwent the procedure in prone-split leg position. A nonpapillary renal puncture was performed. The used access sheaths were 22Fr or 30Fr. Lithotripsy was performed anterogradely with a dual-energy lithotripter with incorporated suction and retrogradely with holmium Yttrium-Aluminum-Garnet laser. RESULTS: A total of 33 patients were included. The initial stone-free rate (SFR) was 84.8% and the final SFR was 90.9%. The median stone size was 35 mm and 60% of patients had staghorn calculi. The prevalence of renal abnormalities was 21.3%, including 3 cases of horseshoe kidney, 2 cases of malrotation and 2 cases with complete duplicated systems. The median operative time was 47 min. The median hospital stay was 3 days and median hemoglobin loss was 1.2 gr/dL. Overall, the complication rate was 9.1%, all being Grade II complications (n = 2 fever and n = 1 transient bleeding). CONCLUSIONS: Nonpapillary prone ECIRS is an effective and safe procedure. Standardization of the procedure is critical to achieve good outcomes. Patients who benefit the most are probably the ones where additional punctures can be avoided using this technique, namely patients with renal abnormalities, incrusted ureteral stents and staghorn stones.

Factors Affecting the Irrigation Fluid Temperature During Laser Lithotripsy: In Vitro Experimental Study.

OBJECTIVE: To investigate the effect of the diameter of laser fiber, pelvis volume, presence and type of the stone on irrigation fluid temperature rise. MATERIAL AND METHODS: A 20ml syringe, 12/14 ureteral access sheath(UAS), a dual-lumen catheter and a thermocouple were used.  The 12/14Fr UAS(Cook Ireland Ltd., Limerick, Ireland) and the Thermocouple(SE001, Pico Technologies, Cambridgeshire, UK) were inserted in the syringe. The syringe was closed allowing outflow from the UAS with rate at 10ml/min. The Quanta Ho 150W(Quanta System, Samarate, Italy) laser was used and fired with 10W(2Jx5Hz), 20W(2 × 10 Hz), 40W(2 × 20 Hz), 60W(2 × 30 Hz). These power settings were tested in different conditions: fibers(200µm, 365µm and 550µm), volumes(5ml, 10ml and 20ml) and artificial stones(soft, hard). The laser was activated for 30 seconds and reactivation was performed when the temperature reached below 26 °C. RESULTS: For all trials 60W of energy resulted in higher temperature rise. No differences were observed when different fibers were used. The highest temperatures (up to 80 °C) for 60W were reported in 5ml syringe and the lowest (<45 °C) with 20ml.  The maximal temperature of >59°C was recorded for the power of 60W(1Jx60Hz). The temperature exceeded 43 °C when power settings >40W were applied. CONCLUSION: Increasing the overall power, increases the irrigation fluid temperature significantly. The smaller the volume of the pelvis, the greater the temperature elevation. The fiber size did not affect the temperature increase pattern. The presence of artificial stones was associated with the absorption of energy emitted by the laser.

Comparison between standard, mini and ultra-mini percutaneous nephrolithotomy for single renal stones: a prospective study.

PURPOSE: Based on the current trend of miniaturization of instruments used in percutaneous nephrolithotomy (PCNL), it is necessary to compare different PCNL modalities regarding their access sheath size used. Thus, the safety and efficacy among standard, mini and ultra-mini PCNL (s-PCNL, m-PCNL, um-PCNL) were compared. METHODS: We performed a prospective, non-randomized trial between January 2018 and July 2020. Patients with stones classified as Guy's stone score grade I were included. The set-up for s-PCNL and m-PCNL included a 30 Fr and 22 Fr percutaneous tract, respectively. In both set-ups, an ultrasonic/ballistic lithotripter was utilized. In the case of um-PCNL, a 12 Fr percutaneous tract was established. A high-power laser was used for lithotripsy. Hemoglobin drop, complication rate, length of hospital stay (LOS), stone-free rate (SFR) and operation time were evaluated. RESULTS: A total of 84 patients, 28 patients per method, were evaluated. Hemoglobin drop was higher in the s-PCNL group when compared to m-PCNL (p = 0.008) and um-PCNL groups (p < 0.001), while um-PCNL group had the slightest hemoglobin drop. LOS was similar between s-PCNL group and m-PCNL group, but um-PCNL group required shorter hospital stay than the other two modalities (p < 0.001). The complication and transfusion rates as well as SFR did not differ between groups. Operation time in the um-PCNL set-up was longer compared to s-PCNL (p < 0.001) and m-PCNL (p = 0.011), whereas s-PCNL and m-PCNL did not differ significantly. CONCLUSION: m-PCNL showed less hemoglobin drop, but similar operation time and SFR when compared to s-PCNL. um-PCNL showed even less hemoglobin drop, but the operation time was longer compared to the two other modalities.