Stent Encrustation Research Articles

Crystallization ripening and erosion of calcium oxalate under the effect of bacteria and a polymer materials surface.

As typical examples of pathological biomineralization, urinary stones and stent encrustation have been associated with bacteria, yet the underlying mechanisms remain unclear. In this study, the effect of Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus on the nucleation and growth of calcium oxalate crystals both in solution and on material surfaces in vitro was investigated. Both bacteria can promote calcium oxalate crystallization, and E. coli shows a prominent ability to boost the nucleation and growth rate. Interestingly, we discovered an Ostwald ripening phenomenon after the initial nucleation on the material surfaces, where larger particles emerge upon the disappearance of small nuclei particles, evident in the case of S. aureas. Over an extended period of time, erosion and disintegration of the crystals was observed when bacteria were involved. Based on these understandings, we developed a new functional surface by synthesizing an antibacterial polypeptoid in-house and utilizing polyurethane as the substrate material. This surface exhibits a synergistic effect that inhibits the formation of calcium oxalate crystals. This study helps to elucidate the role of bacteria in calcium oxalate biomineralization and supports further development of treatment approaches such as anti-encrustation polymer materials.

Comparison of the results of active surgical treatment and serial stenting for urolithiasis in pregnant women

Introduction. Renal colic during pregnancy is a common cause of pain in the lower back. Currently, with a diagnosed kidney or ureter stone, the standard treatment is serial drainage of the urine tract using an internal ureter stent, with replacement of the drainage before delivery, followed by surgery to remove the stone after delivery.Objective. To study the effectiveness and safety of ureteroscopic interventions in the treatment of urolithiasis in pregnant women in comparison with the method of serial drainage of the upper urinary tract during gestation followed by surgical treatment of urolithiasis 4 weeks after delivery.Materials & methods. The study group consisted of 119 patients with a confirmed diagnosis of urolothiasis using instrumental diagnostic methods and a gestational age up to and including the 27th week. Two groups were formed based on treatment approaches for urolithiasis: group 1 included 59 patients (49.6%) who underwent surgical removal of the stone; group 2 included 60 patients (50.4%) who underwent internal ureteral stent replacement every 4 – 6 weeks prior to delivery and subsequent ureteroscopy There were no significant differences in age, body mass index, or number of pregnancies between the two groups.Results. The frequency of complete stone removal in groups 1 and 2 was 96.6 and 96.7%, respectively. The median amount of time spent on urolithiasis treatment in groups 1 and 2 was 60 [45; 72] and 97 [54; 105] minutes, respectively (p = 0.002). Migration of the ureteral stent in group 2 was observed in 13.3% of cases (p = 0.05). Among group 1 patients who underwent ureteroscopic intervention aimed at stone removal, the incidence of internal drainage dislocation was 3.4%. Encrustation of the ureteral stent in groups 1 and 2 was observed among 2 (3.4%) and 17 (28.3%) patients, respectively (p < 0.001). The bed-day (median time in days spent in hospital for drainage replacement and time of surgical treatment of urolithiasis) in groups 1 and 2 was four and eight days, respectively (p < 0.05). The frequency of natural childbirth in groups 1 and 2 was 81.35% and 55.0%, respectively (p = 0.002).Conclusion. Urolithiasis among pregnant women is a complex multifactorial disease that affects not only the health of the mother, but also the condition of the developing foetus. It is possible to perform surgical treatment with high efficiency and low complication rate, which improves the quality of life.

The financial impact of delays to percutaneous nephrolithotomy surgery at a county hospital

AbstractIntroductionPercutaneous nephrolithotomy (PCNL) is a standard management for complex renal stone disease. However, the implications of delays in PCNL are under‐explored. We hypothesized that increased time prior to intervention in a county hospital system would be associated with higher hospital charges, increased clinic and hospital visits, and increased procedural interventions.MethodsA single‐center retrospective chart review of 132 adult patients undergoing PCNL at a county hospital from April 2019 to December 2022 was performed. Groups were organized based on time from diagnosis to surgery (<4 months, 4–6 months, >6 months). Key outcomes included hospital charges, insurance types, ureteral stent versus nephrostomy decompression, presence of stent encrustation, and number of preoperative computed tomography (CT) scans, emergency department (ED) visits, and interventions. Kruskal–Wallis ANOVA was used for determining group differences between continuous variables, and χ2 was used for categorical variables.ResultsA total of 132 PCNLs were analyzed with a median diagnosis‐to‐operating room (OR) period of 135 days. Compared to patients with diagnosis‐to‐OR period less than 4 months, those with PCNL performed in 4–6 months and over 6 months had 7% and 36% higher hospital charges respectively ($27 607 vs. $29 416 vs. $37 622, p = 0.018). Delays to PCNL surgery resulted in more CT scans (p = 0.019), clinic visits (p < 0.001), and interventions (p = 0.003).ConclusionOur study showed that in a medically underserved population, increased diagnosis‐to‐OR period led to increased healthcare utilization, additional procedures, and hospital charges. Changes aimed at reducing the time from diagnosis to surgery could reduce the financial burden for both patients and the healthcare system.

Development and validation of a predictive model for double-J stent encrustation after upper urinary tract calculi surgery

The study is aimed to establish a predictive model of double-J stent encrustation after upper urinary tract calculi surgery. We collected the clinical data of 561 patients with indwelling double-J tubes admitted to a hospital in Shandong Province from January 2019 to December 2020 as the modeling group and 241 cases of indwelling double-J tubes from January 2021 to January 2022 as the verification group. Univariate and binary logistic regression analyses were used to explore risk factors, the risk prediction equation was established, and the receiver operating characteristic (ROC) curve analysis model was used for prediction. In this study, 104 of the 561 patients developed double-J stent encrustation, with an incidence rate of 18.5%. We finally screened out BMI (body mass index) > 23.9 (OR = 1.648), preoperative urine routine white blood cell quantification (OR = 1.149), double-J tube insertion time (OR = 1.566), postoperative water consumption did not reach 2000 ml/d (OR = 8.514), a total of four factors build a risk prediction model. From the ROC curve analysis, the area under the curve (AUC) was 0.844, and the maximum Oden index was 0.579. At this time, the sensitivity was 0.735 and the specificity was 0.844. The research established in this study has a high predictive value for the occurrence of double-J stent encrustation in the double-J tube after upper urinary tract stone surgery, which provides a basis for the prevention and treatment of double-J stent encrustation.

Urological Challenges during Pregnancy: Current Status and Future Perspective on Ureteric Stent Encrustation.

The management of ureter hydronephrosis and urolithiasis during pregnancy has been changed by the adoption of ureteric stents. Despite their broad use for several other conditions, from emergency to elective settings, their complications cannot be ignored. Being most prevalent during pregnancy, urinary tract infections and stent encrustations are particularly common and can affect either fetal growth or maternal-fetal homeostasis, leading to obstetric complications. The main concern associated with ureteric stents is the indwelling time, which could represent the potential trigger of those complications. However, to ensure the optimal management of a ureteric stent during pregnancy, factors such as the grading of encrustations and the presence, size, and location of stones should be evaluated in pre-operative planning. As a consequence, a multimodal approach, including obstetrics, gynecologists, urologists, and nurses, is essential to ensure a complication-free procedure and successful ureteric stent removal. Finally, future research should focus on utilizing biodegradable and biocompatible materials to reduce and even eliminate the complications related to forgotten stents in order to reduce the financial burden associated with stent replacement and the management of stent-encrustation-related complications.

Ureteral Double J Stent Encrustation: Prevalence and Associated Factors

Ureteral Double J Stent Encrustation: Prevalence and Associated Factors

“Forgotten” Encrusted Ureteral Stents, Combined Endourological Approach

Introduction: Ureteral stents have been widely used for drainage of the upper urinary tract during both emergency and elective surgical procedures since 1967. The main pathology in which these stents are used is urolithiasis.Objective: To present our experience with the surgical treatment of patients with “forgotten” encrusted ureteral stents using a combined endourological approach.Materials and methods: Patients with encrusted ureteral stents who underwent endourological procedures from 2016 to 2022 were prospectively evaluated. They were grouped based on the degree of stent encrustation according to the FECal classification. The duration of stent placement, number and types of surgical procedures, number of procedures before complete removal of the stent and concrements, surgery duration, hospital stay, complications, concrement analysis, and frequency of complete concrement removal per surgery were compared between the groups. The combined endourological procedure was performed with the patient placed in the Galdakao-modified supine Valdivia position. This position allows simultaneous antegrade and retrograde endourological access.Results: The study included 46 patients grouped according to the FECal classification. In 38 patients, stents were successfully removed in a single procedure. The mean operative time, concrement-free status, and complication rate were 90.2 ± 19.8 minutes, 78.3%, and 32.6%, respectively. Total encrustation volume was higher for grades IV and V (5.6 ± 1.8 and 7.6 ± 2 cm3) compared with all the other grades. Percutaneous nephrolithotripsy and cystolithotripsy were the most common procedures in grades IV and V. Lithotripsy was commonly used for ureteral stent encrustation, especially in the groups with grades I and III. The operative time was longer in groups IV-V compared with groups I and II because percutaneous nephrolithotripsy was more frequent in these cases. Retrograde intrarenal surgery was performed in 88% of the cases with the combined approach to check whether concrements were present in the renal calyces and pelvis. In 5 cases, a flexible ureterorenoscope was advanced antegradely through a percutaneous access to disintegrate the encrustation of the proximal part of the stent’s ureteral section. Complications occurred in 32.6% of the patients. Most complications (26%) were minor: fever, pain, or gross hematuria. One case required segmental renal artery embolization for bleeding, and antibiotic therapy associated with an attack of pyelonephritis was adjusted in 2 cases.Conclusions: The endoscopic combined approach in the Galdakao-modified supine Valdivia position is a safe and effective technique that allows removal of “forgotten” encrusted stents, in most cases, in a single procedure. The FECal classification seems to be useful for surgical planning and prognosis.

Can Double J stent encrustation be predicted by risk analysis and nomogram?: A retrospective case-control study.

To explore the risk factors and develop a nomogram to predict Double J stent encrustation incidence. The general demographic characteristics and underlying risk factors of 248 patients with upper urinary tract calculus who underwent endoscopic lithotripsy and Double J stenting at the Fifth Affiliated Hospital of Sun Yat-Sen University between January 1st, 2018 and January 1st, 2023 were retrospectively analyzed. Among them,173 patients were randomly selected to form the development cohort. A multivariate logistic regression model was employed to identify the independent risk factors associated with Double J stent encrustation, and a nomogram was developed for predicting its occurrence. Additionally, 75 patients were randomly selected to form the validation cohort to validate the nomogram. Multivariate logistic regression analysis revealed that several factors were significantly associated with Double J stent encrustation: indwelling time (odds ratio [OR]1.051; 95% confidence interval [CI] 1.030-1.073, P < .001), urine PH (OR 2.198; 95% CI 1.061-4.539, P = .033), fasting blood glucose (OR 1.590; 95% CI 1.300-1.943, P < .001), and total cholesterol (OR 2.676; 95% CI 1.551-4618, P < .001).Based on these findings, A nomogram was developed to predict the occurrence of Double J stent encrustation. The nomogram demonstrated good performance with an area under the curve of 0.870 and 0.862 in the development and validation cohorts, respectively. Furthermore, the calibration curve indicated a well-fitted model. We constructed and validated an accessible nomogram to assist urologists in evaluating the risk factors associated with Double J stent encrustation and predicting its likelihood.

A method for detecting ureteral stent encrustations in medical CT images based on Mask-RCNN and 3D morphological analysis.

To develop and validate a method for detecting ureteral stent encrustations in medical CT images based on Mask-RCNN and 3D morphological analysis. All 222 cases of ureteral stent data were obtained from the Fifth Affiliated Hospital of Sun Yat-sen University. Firstly, a neural network was used to detect the region of the ureteral stent, and the results of the coarse detection were completed and connected domain filtered based on the continuity of the ureteral stent in 3D space to obtain a 3D segmentation result. Secondly, the segmentation results were analyzed and detected based on the 3D morphology, and the centerline was obtained through thinning the 3D image, fitting and deriving the ureteral stent, and obtaining radial sections. Finally, the abnormal areas of the radial section were detected through polar coordinate transformation to detect the encrustation area of the ureteral stent. For the detection of ureteral stent encrustations in the ureter, the algorithm's confusion matrix achieved an accuracy of 79.6% in the validation of residual stones/ureteral stent encrustations at 186 locations. Ultimately, the algorithm was validated in 222 cases, achieving a ureteral stent segmentation accuracy of 94.4% and a positive and negative judgment accuracy of 87.3%. The average detection time per case was 12s. The proposed medical CT image ureteral stent wall stone detection method based on Mask-RCNN and 3D morphological analysis can effectively assist clinical doctors in diagnosing ureteral stent encrustations.

New insights into the prevention of ureteral stents encrustation

Abstract Ureteral stents are commonly used medical devices for the treatment of urinary system diseases. However, while providing benefits to patients, they often give rise to various issues, with stent encrustation being a major concern for clinical physicians. This phenomenon involves the formation of attached stones on the stent’s surface, leading to potential complications such as increased fragility and laxity of the ureter, difficulties in stent removal, and a higher risk of stent fracture. Therefore, this review starts from the pathological mechanisms of stone formation and discusses in detail the two major mechanisms of stent encrustation: the conditioning film and the biofilm pathway. It also examines multiple risk factors associated with ureteral stents and patients. Furthermore, the review updates the research progress on the structure, materials, and bio-coatings of ureteral stents in the prevention and treatment of stent encrustation. It presents new insights into the prevention and treatment of stent encrustation. This includes individualized and comprehensive clinical guidance, the use of novel materials, and early intervention based on physiological and pathological considerations. Ultimately, the study offers an encompassing overview of the advancements in research within this field and provides the latest insights into strategies for preventing and treating stent encrustation.

Management and cost of stent encrustation in pregnancy.

Management and cost of stent encrustation in pregnancy.

Stent-ception: implementation of soft double-J stents in the ureteric Memokath-051&lt;sup&gt;TM&lt;/sup&gt; in bilateral ureteric stricture post radiotherapy for advanced prostate cancer

Narrowing of ureter can be due to malignant or benign causes. Temporary double-J (DJ) stents, various metallic stent designs, or definitive corrective surgery can be the options management for ureteric stricture. As an alternative from DJ stents, Memokath-051TM (MMK-051TM) can be inserted in strictured ureters post radiotherapy for advanced prostate cancer patients. We present a case of an advanced prostate cancer which bilateral DJ Stents placed within MMK-051TM. A 76-year-old man with underlying hormone sensitive advanced prostate cancer completed radiotherapy. Post radiotherapy he developed bilateral ureteric strictures and bilateral DJ stents inserted. He had to underwent multiple change of stents due to blockage. Patient had MMK-051TM inserted, however complicated with blockage due to encrustation. Improvisation method done by putting the bilateral DJ stents within the MMK-051TM. Patient had no more blockage of MMK-051TM after the placement of DJ stents within it. However, patient succumbed to death a year after the last procedure. Our case report highlighted encrustation of metallic ureteric stents and a novel approach to overcome this problem. Introduction of additional DJ stents not only reduced the incidence of MMK-051TM blockage but also improved the quality of life of the patient.

Bladder stone formation due to neglected double J stent: a case report.

Double J (DJ) stents are commonly used in genitourinary procedures, but they can lead to complications including infection, hematuria, encrustation, and stone formation. The longer the duration of encrustation, the greater the risk of complications and renal dysfunction. Forgotten stents pose challenges for patients and can require endourological or open surgical procedures. A 40-year-old man with hypertension and coronary artery disease had a forgotten DJ stent for 3 years, causing suprapubic pain and dysuria. Kidney, ureter, and bladder (KUB) revealed a coiled DJ stent with a large bladder stone and encrustation, and an open cystolithotomy was successfully performed. Recovery was uneventful, and the patient was discharged without complication. Ureteral stents, including the DJ stent, are commonly used for urological conditions but can cause complications if retained beyond the intended timeframe. Optimal timing for stent removal is crucial, and patients' healthcare knowledge and adherence are critical to preventing retention. KUB X-ray can evaluate stent encrustation and bladder stones. Cystoscopy is the typical approach for stent removal, but supplementary interventions may be necessary. Open surgery was recommended for removing a large bladder stone and encrusted stent in this case. Timely removal of DJ stents is crucial to avoid complications. Extended retention can cause problems such as encrustation and stone formation. Patient education and adherence are essential to prevent retention and forgetfulness. This case report highlights the importance of careful management of patients with DJ stents for optimal outcomes and prevention of complications.

Modified telescopic sheath method for exchange of luminally encrusted ureteral stents

A novel telescopic access sheath technique has beendescribed to maintain access to the ureterincases of stent encrustation, placing a suture onthe externalised distal end of the stentfollowedby advancing a sheath over to peeloffencrustations and maintain access in theureter,as well as application of this techniqueinachild. Herein we present a modification of thetelescopic sheath technique thatallows exchange of luminally encrusted stentswithoutrequiring passage of the sheathintothe ureter or ureteroscopy alongside the stent.

Relationship between Urinary Parameters and Double-J Stent Encrustation.

(1) Background: This study aimed to determine the relationship between metabolic urine conditions and the formation, severity, and composition of encrustations in ureteral stents. (2) Methods: Ninety stone-former patients requiring a double-J stent were prospectively enrolled. We collected 24 h metabolic urine samples and demographic data, including indwelling time and previous stone composition. The total deposit weight was obtained, and a macroscopic classification according to the degree of encrustation (null, low, moderate, and high) was created, allowing for intergroup comparisons. Stereoscopic and scanning electron microscopy were performed to identify the type of embedded deposits (calcium oxalate, uric acid, and infectious and non-infectious phosphates). (3) Results: In total, 70% of stents were encrusted; thereof, 42% had a moderate degree of encrustation. The most common encrustation type was calcium oxalate, but infectious phosphates were predominant in the high-encrustation group (p < 0.05). A direct correlation was observed between the purpose-built macroscopic classification and the encrustation weights (p < 0.001). Greater calciuria, uricosuria, indwelling time, and decreased diuresis were observed in stents with a higher degree of encrustation (p < 0.05). The urinary pH values were lower in patients with uric acid encrustations and higher in those with infectious phosphate encrustations (p < 0.05). When compared to non-encrusted stents, patients with calcium-oxalate-encrusted stent showed greater calciuria, phosphaturia, indwelling time, and reduced diuresis; patients with uric-acid-encrusted stent showed greater uricosuria; and patients with infectious and non-infectious phosphate encrustation showed greater urinary pH (p < 0.05). (4) Conclusions: Metabolic urine conditions play a critical role in the formation, composition, and severity of double-J stent encrustation.

Identifying ureteral stent encrustation using machine learning based on CT radiomics features: a bicentric study.

To develop and validate radiomics and machine learning models for identifying encrusted stents and compare their recognition performance with multiple metrics. A total of 354 patients with ureteral stent placement were enrolled from two medical institutions and divided into the training cohort (n = 189), internal validation cohort (n = 81) and external validation cohort (n = 84). Based on features selected by Wilcoxon test, Spearman Correlation Analysis and least absolute shrinkage and selection operator (LASSO) regression algorithm, six machine learning models based on radiomics features were established with six classifiers (LR, DT, SVM, RF, XGBoost, KNN). After comparison with those models, the most robust model was selected. Considering its feature importance as radscore, the combined model and a nomogram were constructed by incorporating indwelling time. Accuracy, sensitivity, specificity, area under the curve (AUC), decision curve analysis (DCA) and calibration curve were used to evaluate the recognition performance of models. 1,409 radiomics features were extracted from 641 volumes of interest (VOIs) and 20 significant radiomics features were selected. Considering the superior performance (AUC 0.810, 95%CI, 0.722-0.888) in the external validation cohort, feature importance of XGBoost was used as a radscore, constructing a combined model and a nomogram with indwelling time. The accuracy, sensitivity, specificity and AUC of the combined model were 98, 100, 97.3% and 0.999 for the training cohort, 83.3, 80, 84.5% and 0.867 for the internal cohort and 78.2, 76.3, 78.8% and 0.820 for the external cohort, respectively. DCA indicates the favorable clinical utility of models. Machine learning model based on radiomics features enables to identify ureteral stent encrustation with high accuracy.

Comparison of Ureteral Stent Biomaterials: Encrustation Profile in Lithogenic Artificial Urine Models.

Ureteral stent encrustation significantly limits indwelling time and can lead to downstream urological problems. However, no ideal polymeric biomaterials have been shown to completely resist encrustation in long-term urine exposure. Recently, 2-hydroxyethyl methacrylate (HEMA)-coated Pellethane was reported as a promising biomaterial resistant to encrustation. This study compared HEMA-coated Pellethane to commercially available stents under two different artificial urine environments. To evaluate the degree and composition of encrustation on HEMA-coated Pellethane, Boston Scientific Tria, Bard InLay Optima, Cook Universa Hydrogel, and Cook Black Silicone stents were used at various dwelling times in two different artificial urine environments. In a batch-flow model, samples of stents were suspended in an artificial urine solution (AUS) at 37 °C. Every 24 h for 11 weeks, 50% of the AUS would be replaced with fresh components using a programmable peristaltic pump system. The stent materials were removed at suitable time intervals and air-dried for 24 h under sterile conditions before follow-up analysis. SEM was used to assess the degree of encrustation, and inductively coupled plasma mass spectrometry (ICP-MS) was employed to quantify the encrusted compositions, specifically for calcium, magnesium, and phosphorus. We measured the weight gain over time due to encrusted deposits on the stents and quantified the amount of Ca, Mg, and P deposited on each encrusted stent. After the 11 week trial, HEMA-coated Pellethane showed the most average mass change. SEM showed that HEMA-coated Pellethane was fully encrusted in just 2 weeks in the AUS environments, and ICP-MS showed that Ca is the most abundant deposit. Among all the tested stents, Black Silicone performed the best. The two AUSs were formulated to encrust more rapidly than physiological conditions. HEMA-coated Pellethane is not an ideal stent material, while silicone is a promising material for advancing ureteral stents.

Analysis of Stenting versus Non-Stenting in patients Undergoing Ureteroscopic Lithotripsy for Management of Ureteric Calculi

Background: Ureteroscopic lithotripsy (URL) for ureteric calculi is commonly followed by ureteric stenting in around 60% of patients. However, its use for ureteric stones is debatable due to the stent-related symptoms and extra risks of stent migration, stent encrustation, and vesicoureteral reflux. Aim: To compare stenting to no-stenting in terms of mean operative time and mean hospital stay in patients receiving ureteroscopic lithotripsy for the treatment of ureteric calculi. Methods: This RCT, conducted at the Armed forces institute of urology Rawalpindi, included 104 patients aged 18 to 65 years with newly diagnosed ureteric calculi of 10-20 mm in size. They were subsequently separated into two equal groups, group A patient underwent ureteric stenting, and group B patients without a ureteric stent after uncomplicated calculus clearance with URL. Operative time was recorded in minutes, and hospital stay was measured in hours. Data were analyzed by SPSS version 22. Results: The mean (SD) operative time was significantly longer in group A as compared to Group B, 48.02 ± 4.33 and 33.67 ± 2.27 min, respectively (p-value &lt;0.0001), similarly mean duration of hospital stay for Group B patients was significantly shorter as compared to Group A patients (21.94 ± 2.29 versus 27.10 ± 4.16 hours) which were significant statistically (p &lt; 0.0001). Conclusions: Non-stenting has reduced mean hospital stay duration and reduced mean operative time in comparison with stenting after URL; thus, unless desirably needed stenting in URL should be avoided. Keywords: Ureteroscopy (URL), DJ stenting, operative time. hospital stay. Keywords: Ureteroscopy (URL), DJ/JJ stenting, operative time. Hospital stay.

Analysis of Stenting versus Non-Stenting in patients Undergoing Ureteroscopic Lithotripsy for Management of Ureteric Calculi

Background: Ureteroscopic lithotripsy (URL) for ureteric calculi is commonly followed by ureteric stenting in around 60% of patients. However, its use for ureteric stones is debatable due to the stent-related symptoms and extra risks of stent migration, stent encrustation, and vesicoureteral reflux. Aim: To compare stenting to no-stenting in terms of mean operative time and mean hospital stay in patients receiving ureteroscopic lithotripsy for the treatment of ureteric calculi. Methods: This RCT, conducted at the Armed forces institute of urology Rawalpindi, included 104 patients aged 18 to 65 years with newly diagnosed ureteric calculi of 10-20 mm in size. They were subsequently separated into two equal groups, group A patient underwent ureteric stenting, and group B patients without a ureteric stent after uncomplicated calculus clearance with URL. Operative time was recorded in minutes, and hospital stay was measured in hours. Data were analyzed by SPSS version 22. Results: The mean (SD) operative time was significantly longer in group A as compared to Group B, 48.02 ± 4.33 and 33.67 ± 2.27 min, respectively (p-value &lt;0.0001), similarly mean duration of hospital stay for Group B patients was significantly shorter as compared to Group A patients (21.94 ± 2.29 versus 27.10 ± 4.16 hours) which were significant statistically (p &lt; 0.0001). Practical implication: Every URS procedure does not need stenting. Patients with uncomplicated URS should not under DJ stenting. URS without stenting reduces hospital stay and operative time. Conclusions: Non-stenting has reduced mean hospital stay duration and reduced mean operative time in comparison with stenting after URL; thus, unless desirably needed stenting in URL should be avoided. Keywords: Ureteroscopy (URL), DJ stenting, operative time. hospital stay. Keywords: Ureteroscopy (URL), DJ/JJ stenting, operative time.Hospitalstay.

Comment on: "Ureteral stent encrustation: evaluation of available scores as predictors of a complex surgery".

Comment on: "Ureteral stent encrustation: evaluation of available scores as predictors of a complex surgery".