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.

Sphincter preservation techniques during radical prostatectomies: Lessons learned.

Prolonged urinary incontinence represents one of the most severe complications after a radical prostatectomy procedure, significantly affecting patients' quality of life. In an attempt to ameliorate postprostatectomy continence rates, several sphincter preservation techniques have been reported. The purpose of this article is to report several different sphincter preservation techniques and identify the ones which affect postoperative outcomes the most. For our narrative review, PubMed was searched using the keywords "sphincter," "continence," "preservation," "techniques," and "prostatectomy." Other potentially eligible studies were identified using the reference lists of included studies. Sphincter preservation techniques can be summarized into bladder neck preservation, minimizing injury to the external urethral sphincter, and preserving the maximal length of the external sphincter and of the membranous urethra. Three anatomical structures must be recognized and protected in an attempt to maintain the sphincter complex: the bladder neck, the external urethral sphincter and the musculature of the membranous urethra. While there is strong evidence supporting the importance of bladder neck preservation, the role of maximal preservation of the external sphincter and of the intraprostatic part of the membranous urethra in improving continence rates has not yet been reported in a statistically significant manner by high-quality studies.

Super pulsed thulium fiber laser outcomes in retrograde intrarenal surgery for ureteral and renal stones: a systematic review and meta-analysis.

BACKGROUND: Laser lithotripsy using a thulium fiber laser (TFL) has become an effective treatment option for small renal stones with low complication rates. TFL has a higher absorption coefficient, smaller fibers, and better pulse rate capability. METHODS: We conducted a systematic review and meta-analysis to evaluate the published evidence regarding TFL's lithotripsy performance in retrograde intrarenal surgery (RIRS), for which we primarily assessed the outcomes of stone-free rate, operation time, and complications. We searched different databases from inception to April 2023. We assessed the methodological quality and risk of bias using the Cochrane Risk of Bias tool for randomized trials and the ROBINS-I tool for non-randomized studies. We used a random-effects model for meta-analysis and assessed heterogeneity using the I2 statistic. RESULTS: Twelve published studies evaluated the efficacy of RIRS using a TFL for treating renal and ureteral stones. The meta-analysis revealed a predicted stone-free rate of 89.37% (95% CI: 83.93% to 93.12%), indicating that, on average, approximately 89.37% of patients achieved a stone-free state after treatment. The substantial heterogeneity among the studies was evident, as shown by a Q-value of 33.1174 and a p-value of 0.0003. The I2 value of 69.80% (95% CI: 25.91% to 92.02%) highlighted the proportion of variability attributed to genuine heterogeneity across the studies. Moreover, the H2 value 3.31 (95% CI: 1.35 to 12.53) indicated significant heterogeneity beyond random chance. The estimated overall effect size (logit-transformed) of 2.1289 was highly statistically significant (z = 8.7648, p < 0.0001) with a confidence interval of 1.6528 to 2.6049. The reported complications varied across studies, encompassing Clavien grade I-II complications in most cases, with a subset experiencing more severe Clavien grade III-V complications. Additionally, other studies noted a range of complications, such as haematuria, fever, transient creatinine elevation, and postoperative issues like bleeding, pain, and sepsis. CONCLUSION: This meta-analysis suggests that RIRS using TFL is an effective and safe treatment option for renal and ureteral stones, with high stone-free and low complication rates. The included studies exhibited a low risk of bias and were of high quality. However, more extensive randomized controlled trials with extended follow-up periods are needed to investigate this technique's efficacy and safety.

Effect of patient positioning on anesthesiologic risk in endourological procedures.

Objective: The objective is to compare supine and prone positions in terms of arterial blood gas during lithotripsy endourology procedures in different stages. Material and Methods: Cases of during lithotripsy endourology procedures in our department from March to September 2020 were included prospectively. The variables registered were body mass index, age, the American Society of Anesthesiologists (ASA) score, diabetes mellitus, positive end-expiratory pressure (PEEP), FiO2, stone size, stone location, procedural type, position, procedure duration, PaO2, SaO2, PaCO2, pH, and dynamic compliance. PaO2, SaO2, PaCO2, pH, and dynamic compliance were recorded at the beginning of the procedure, 5 min later, 15 min later, and at the end of the procedure. Results: Thirty patients in prone position and 30 in lithotomy position were included in this study. Patients in prone position underwent percutaneous nephrolithotomy, and patients in supine/lithotomy underwent retrograde intrarenal surgery or ureteroscopy. Statistically significant differences were found in PEEP, duration, PaO2 at the beginning, SaO2 at the beginning and at the end of the procedure, PaCO2 at the beginning and at minute 5 and pH at the beginning of the surgery. The saturation PaO2 increased significantly on prone position and was statistically significantly better at the end of the surgery. Conclusions: Both prone and supine positions were safe regarding anesthesiologic risk and had no clinically relevant differences in terms of individual comparisons in arterial blood gas parameters in static moments of the procedure. Prone position was related to an increase in PaO2 and a drop in PaCO2 gradually from the beginning to the end of the surgery.

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.

Successful endoscopic management for early manifested postcesarean section uretero-uterine fistula: A case report and literature review.

We report a rare case of post-cesarian section uretero-uterine fistula (UUF) in a 36 years old female who presented on a postoperative day 5 with paradoxical urine incontinence and occasional normal urethral voiding. After a complete evaluation, Cystoscopy and right internal JJ ureteric stent insertion was done; the patient had a dramatic response; she was completely dry until the stent was removed three months later with complete healing of UUF. To our knowledge, the present case is the 4th reported with successful endoscopic management for post-obstetrics and gynecological procedures Uretero-Uterine fistula.

Does ureteral access sheath have an impact on ureteral injury?

OBJECTIVE: To present a well-organized review about ureteral access sheath impact on ureteral injury. MATERIALS AND METHODS: Systemic search on literature was done. Total of 3766 studies observed by two urologists and results were unified. A Prisma diagram was used for eliminating irrelevant studies and at the end of elimination process 28 studies were found eligible for this review. RESULTS: Not only clinical studies but also comparative experimental animal studies show that there is no significant data to claim that ureteral access sheath insertion causes more ureteral injury. Pre-stented patients were found to be at lower risk for ureteral injury. Risk of progression to ureteral injury seems to be low even if ureteral injury occurs with insertion of ureteral access sheath. CONCLUSION: Summary of studies' results indicate that use of ureteral access sheath doesn't increase ureteral injury. This review may help understanding safety profile of ureteral access sheath on evidence-based level. There is not enough data to make a statement that ureteral access sheath prevents ureteral injury.

The use of S-curved coaxial dilator for urethral dilatation: Experience of a tertiary department.

OBJECTIVE: Urethral strictures can be treated by urethral dilation, optical internal urethrotomy, or open surgical reconstruction (urethroplasty). Urethral dilation is done with filiforms and followers, balloons, or coaxial dilators inserted over a guidewire. The S-curved coaxial dilator (SCCD) was designed to facilitate the passage of the dilator through the stricture and the urethra because it imitates the curved anatomy of the male urethra. This study presents our experience with SCCD. MATERIALS AND METHODS: We used this kind of dilation in 310 patients. The technique included the insertion of a hydrophilic floppy-tipped guidewire through the urethra directly into the bladder under fluoroscopic control. The SCCDs were then inserted over the guidewire. Dilators of gradually increased size from 8F to 20F were used. The follow-up of the patients includes uroflowmetry and measurement of postvoid residual at 4 weeks, 6 months, or in the case of a recurrence of symptoms. RESULTS: The age of the patients were 69.08 ± 15.77 years. The causes of urethral stricture were iatrogenic (n = 114), traumatic (n = 35), infectious (n = 22), and of unknown origin (n = 139). The stricture length was 1.62 ± 0.85 cm. The mean number of dilations needed per case was 2 (range: 1-15), and the time between the dilations was 212.19 ± 253.9 days. We had seven failures. CONCLUSION: We propose the S-curved coaxial dilators for urethral dilation as a safe and effective technique because of their similarity to the shape of the male urethra and because of their hydrophilic coating.

Laparoscopic sacrocolpopexy using barbed sutures for mesh fixation and peritoneal closure: A safe option to reduce operational times.

INTRODUCTION: Laparoscopic sacrocolpopexy (LSC) has established itself as a safe method for the management of pelvic organ prolapse (POP). Laparoscopic suturing is a time-consuming intraoperative task during LSC. Self-retaining barbed sutures (SBSs) are known to reduce the operative time in laparoscopic cases. The current study aimed to evaluate the efficacy and safety of SBS during the performance of LSC. MATERIALS AND METHODS: Twenty female patients with symptomatic POP were treated with LSC by an expert surgeon. The preoperative evaluation included the International Continence Society POP-quantification (POP-Q) and the prolapse-specific quality-of-life questionnaire Mesh fixation was performed with SBS anteriorly on the anterior vaginal wall and posteriorly on the levator ani muscle. A 5-mm titanium tacking device was used for promontofixation. The peritoneum was also closed with an SBS. RESULTS: Mean patient's age was 63 years (range: 50-79 years). According to POP-Q, system 3 patients (15%) had Stage I, 12 patients (60%) had Stage II, 3 patients (15%) had Stage III, and 2 patients (10%) had Stage IV prolapse. Concomitant hysterectomy was performed in 14 patients, respectively. Mean operative time was 99.75 (range: 65-140) min, mean blood loss was 57.75 (range: 30-120) ml. One patient had a bladder perforation intraoperatively, and three patients developed transient fever postoperatively. One patient had a recurrent cystocele and three patients recurrent rectocele. CONCLUSIONS: The current study renders the use of SBS during LSC to be safe and efficient. Further comparative studies would elucidate the impact of the use of SBS in LSC.

Deep sedation in GreenLight laser prostatectomy.

INTRODUCTION: Evaluation of ketamine and propofol combination for the performance of photoselective vaporization of prostate (PVP). PATIENTS AND METHODS: Twenty-six patients undergoing PVP for benign prostatic hyperplasia were included in the study. Co-morbidities were present in 24 patients. Midazolam 2 mg intravenous was administered for the induction to anesthesia. Propofol (10 mg/ml) and ketamine (1 mg/ml) were administered with the use of two pumps. An initial bolus dose of 0.03 ml/kg of propofol and 5 mg of ketamine was administered intravenously. The anesthesia was maintained by continuous infusion of 0.01 ml/kg/min of propofol and 2 ml/min of ketamine. Fentanyl was administered when deemed necessary. The level of sedation, peri-operative parameters and side-effects were recorded. RESULTS: The average periods from the induction of anesthesia and intraoperative infusion were 12.38 ± 5.84 min and 59.5 ± 22.15 min, respectively. Average propofol and total ketamine dose were 85.5 ± 10.62 µg/kg/min and 144.9 ± 45.62 mg, respectively. The average dose of fentanyl administered was 29.81 ± 27.40 µcg. An average period between the end of the infusion and the discharge to the urology clinic was 34.62 ± 22.89 min. Ten patients experienced nausea and five eventually vomited. Hallucinations were observed in five cases while visual disturbances in two patients. CONCLUSION: The combined use of ketamine and propofol for the performance of PVP proved to be an efficient method for anesthesia. The "deep sedation" provided by these drugs was not associated with significant side-effects. Moreover, the use of the above method is indicated in patients with significant co-morbidities that should undergo PVP.

Laparoscopic simple prostatectomy: A reasonable option for large prostatic adenomas.

AIM OF THE STUDY: In this work, surgical technique followed by two academic departments on laparoscopic simple prostatectomy (LSP) of large prostatic adenomas is being described. MATERIALS AND METHODS: The initial cumulative experience from 11 patients with lower urinary tract symptoms of benign prostatic hyperplasia origin subjected to LSP is being presented. RESULTS: All cases had prostatic adenomas greater than 80 ml. Mean operation time was 99.5 min (values from 70 to 150 min) and mean blood loss was 205 ml (values from 100 to 300 ml). Blood transfusion was deemed necessary in one case. Bladder catheter was removed successfully on postoperative day 5 in all cases. No significant postoperative complication was noted. At a 3 months follow-up a significant decrease in International Prostate Symptom Score (IPSS) was evident in all patients (mean IPSS 27.7 vs. 15.3 preoperative vs. postoperative accordingly). CONCLUSIONS: According to our data and similarly to the rest of the LSP literature, laparoscopic excision of voluminous prostatic adenomas is a feasible and safe procedure. Nevertheless, further investigation including a larger number of patients and long-term follow-up is deemed necessary before making definite conclusions regarding the approach.

The full metallic double-pigtail ureteral stent: Review of the clinical outcome and current status.

The full metallic double-J ureteral stent (MS) was introduced as a method for providing long-term drainage in malignant ureteral obstruction. Experimental evaluation of the MS revealed that its mechanical features allow efficient drainage in difficult cases, which could not be managed by the insertion of a standard polymeric double-J stent. Clinical experience with the MS showed controversial results. Careful patient selection results in efficient long-term management of malignant ureteral obstruction. The use of the MS should also be considered in selected benign cases. Major complications are uncommon and the minor complications should not hinder its use. Experience in pediatric patients is limited and warrants additional study. The cost-effectiveness of the MS seems to be appropriate for long-term treatment. Further investigation with comparative clinical trials would document the outcome more extensively and establish the indications as well as the selection criteria for the MS.

In vitro evaluation of ureteral contractility: a comparative assessment of human, porcine and sheep ureteral response to vardenafil.

OBJECTIVES: Basic science studies of ureteral physiology and pathophysiology are commonly performed on animal ureters due to several limitations associated with human ureteral sampling. In this work we question whether animal ureters are good replicas of human ureteral behavior for pharmacological studies. MATERIALS AND METHODS: Ureteral rings from human, porcine and ovine ureters underwent the same organ bath protocol. After stimulation with KCl, ureters were subjected to different doses of vardenafil. Basic contractility and ureteral response to vardenafil were analyzed. RESULTS: A different pattern of basic contractility was evidenced between species. Vardenafil administration induced a dose-dependent reduction in KCl-induced amplitude increase in human ureters and a dose-dependent reduction in autonomic contractile rhythm of porcine and ovine ureters. Although animal ureters could predict the relaxant response of human samples to vardenafil, its effect would have been overestimated using only animal models. CONCLUSIONS: Human ureteral investigations cannot entirely be replaced by existing animal models since results of the latter will vary significantly according to the tested pharmaceutical agent.

'Scarless' laparoscopic urologic surgery by the combination of mini-laparoscopic and laparoendoscopic single-site surgery equipment.

OBJECTIVE: We evaluated reconstructive and oncological laparoendoscopic single-site surgery (LESS) combined with mini-laparoscopic instruments as standard equipment. PATIENTS AND METHODS: 30 patients underwent reconstructive and oncological LESS: mini-laparoscopic-assisted LESS pyeloplasty (LESS-P, n = 18), mini-laparoscopic-assisted LESS partial nephrectomy (LESS-PN, n = 7) or mini-laparoscopic-assisted LESS radical prostatectomy (LESS-RP, n = 5). Perioperative data were prospectively collected. RESULTS: The 18 LESS-P cases had operative times ranging between 120 and 180 min (average 147.9 min). Estimated blood loss ranged between 100 and 300 ml (average 202.1 ml). Two patients required additional management for failed reconstruction. LESS-PN was performed in 7 patients with tumor size ranging between 2.5 and 3.8 cm (average 2.7 cm). Average operative time and blood loss were 155 (140-180) min and 321.4 (250-550) ml, respectively. Renal artery clamping took place in 1 case. LESS-RP was performed in 5 patients; average operative time was 156 (140-180) min and average blood loss 196 (100-400) ml. Functional and oncological outcome was directly comparable to laparoscopic radical prostatectomy. CONCLUSION: The combination of LESS and mini-laparoscopic instrumentation as routine equipment of reconstructive LESS reveals a different perspective for 'scarless' urologic surgery.

Laparoscopic radical and partial nephrectomy: The clinical efficacy and acceptance of the techniques.

The laparoscopic approach has been established as the surgical procedure of choice for radical nephrectomy during the recent years. The advantages of the laparoscopic radical nephrectomy in comparison to the open approach are well-documented. The oncological results of the laparoscopic approach are similar to the open procedure while the post-operative morbidity is lower. Laparoscopic partial nephrectomy seems to gain ground to its open counterpart, as the accumulation of experience in the technique grows. In this review, a PubMed search in the latest literature on radical and partial laparoscopic nephrectomy took place and the outcome of the search is presented. Several issues about the surgical techniques and clinical efficacy are discussed. In addition, the preliminary experience in laparoscopic nephrectomy of one of the authoring institutions is also presented.

Primary neuroendocrine tumor of the testis.

Testicular neuroendocrine tumor is rare. It accounts for less than 1% of all testicular neoplasms. More than 60 cases have been published in the literature. A 27-year-old man presented with left testicular mass and underwent radical orchidectomy. Histological examination showed neuroendocrine tumor, confirmed by immunohistochemistry and electron microscopy. The patient showed no evidence of metastasis over 1-year follow-up post-orchidectomy in spite of extensive tumor necrosis.

Drug-eluting metallic stents in urology.

Drugeluting metal stents (DESs) have been extensively used in coronary and vascular disease. This type of stents has been proven to provide significantly lower restenosis rates due to the reduction of neo-intimal hyperplasia in comparison to the traditionally used bare metal stents (BMSs). The latter stents have been evaluated for more than a decade in urological practice in an attempt to provide permanent relief of urethral or ureteral obstruction. Although the initial results were promising, long-term experience revealed significant complications, which are mainly attributed to stent-related hyperplastic reaction compromising stent patency. The favorable experience of vascular DESs led to the application of DESs in both the urethra and ureter of animal models. These experimental results demonstrated a reduction of hyperplastic reaction of DESs in comparison to BMSs. Nevertheless, clinical data are currently not available. Considering the fact that DESs are under continuous development, the use of DESs in urology holds promise for the future and seems to be an intriguing field.

Direct effects of vardenafil on the ureter: in vitro investigation and potential clinical applications of intralumenal administration.

Local intralumenal administration of substances with beneficial effects over the ureter appears to be a very attractive route for the administration of drugs to the urinary system, avoiding systemic adverse reactions associated with per os administration. This work investigates whether vardenafil is a good candidate for local intralumenal ureteral administration. More precisely, we examined the effect of vardenafil on human ureter contractility and on the viability of cultured human urothelial cells (hUC) and bladder smooth muscle cells (hBSMC). Our study revealed that vardenafil induced a dose-depended relaxation of isolated human ureteral tissue. In addition, growth and cell viability of cultured hBSMC and hUC remained unaltered after vardenafil application. Based on the above, this selective phosphodiesterase type 5 inhibitor can be considered as a promising pharmacologic agent for local intralumenal administration in clinical conditions in which ureteral dilation might be beneficial.

Laparoendoscopic single-site surgery in kidney surgery: clinical experience and future perspectives.

Laparoscopic surgery of the upper urinary tract has reduced the morbidity related to large abdominal incisions and has resulted in significant advantages over open surgery. Nevertheless, the pursuit for even more minimally invasive alternatives to laparoscopy has led to the concept of scarless surgery and the approach of laparoendoscopic single-site surgery (LESS). LESS is currently a feasible approach for the majority of kidney surgical procedures, and there is intense debate regarding its efficiency and advantages. In the present review of the literature, the current status of upper urinary LESS and its advantages and disadvantages, as well the technological and technical evolution, are presented.