JJ Ureteric Stent Research Articles

1115 Assessing Patient Understanding of Treatment Indications and Follow-Up Procedures Following Emergency Ureteric Stent Insertion: A Single Centre Study

Abstract Aim Ureteric stents are inserted to maintain urinary drainage from the kidney to the bladder in the presence of ureteral obstruction or injury. Over the last 24 months, multiple stents have been retained at our institution, requiring additional invasive surgery to remove encrusted stents with associated loss of kidney function, infection, and morbidity. The aim of this audit is to assess patients’ understanding of the indications for ureteric stent insertion, duration of treatment and how to arrange timely stent removal to avoid the risk of further complications. Method We collected prospective data from patients undergoing emergency JJ-ureteric stent insertion within the Urology department of Northampton General Hospital. We assessed patient understanding of stent indications, treatment duration and stent removal using a questionnaire format. Results All patients surveyed were aware of the indications for stenting. 75% of patients were aware of the minimum duration of stent treatment, however more than half of patients were unaware of when their stent needed to be removed. All patients surveyed did not know how to arrange a stent removal or change, or who to contact regarding this. Conclusions There is a notable lack of patient knowledge and understanding regarding stent removal. We have designed, and plan to implement, a stent passport to provide patients with the relevant information regarding the indications for stenting, duration of treatment and contact details to arrange stent removal. We plan to re-audit patient understanding and outcomes following implementation of the stent passport.

Pyeloplasty in Children with Ureteropelvic Junction Obstruction and Associated Kidney Anomalies: Can a Robotic Approach Make Surgery Easier?

Robot-assisted pyeloplasty is widely used in pediatric surgery because of its well-known advantages over open or laparoscopic surgery. The aim is to explore our experience and evaluate the achievements we have made. We evaluated patients undergoing robotic pyeloplasty from January 2016 to November 2021, including those who presented with a ureteropelvic junction obstruction associated with other anomalies of the kidney. The parameters examined were: age, weight, associated renal malformations, conversion rate, operative time, and intra- and postoperative complications. Of 39 patients, 7 (20%) were included, of whom 5 (71%) were male and 2 (29%) were female. The mean age at surgery was 84 months (range 36-180 months), and the mean weight at surgery was 24.4 kg (range 11-40 kg). In five (71%) patients the ureteropelvic junction obstruction (UPJO) was left-sided and in two (29%) it was right-sided. In four (57%) cases, UPJO was associated with a horseshoe kidney, right-sided in one (25%) patient, and left-sided in the other three (75%). A 180° rotation of the kidney was present in one (14%) patient. Nephrolithiasis was present in two (29%) patients. The mean operative time was 160 min (range 140-240 min). The average bladder catheter dwell time was 1 day (range 2-3 days), while the average abdominal drainage dwell time was 2 days (range 2-4 days). The mean hospitalization time was 4 days (range 3-9 days). On average, after 45 days (range 30-65) the JJ ureteral stent was removed cystoscopically. No intraoperative complications were reported, while one case of persistent macrohematuria with anemia requiring blood transfusion occurred postoperatively. Ureteropelvic junction obstruction might be associated with other congenital urinary tract anomalies such as a duplicated collecting system, horseshoe kidney, or pelvic kidney. These kinds of malformations can complicate surgery and require more attention and accuracy from the surgeon. Our experience shows that, with regards to the robotic learning curve required for pyeloplasty, the treatment of the ureteropelvic junction in these situations does not present insurmountable difficulties nor is burdened by complications. The application of robot-assisted surgery in pediatric urology makes difficult pyeloplasties easier.

Does prophylactic antibiotics post pediatric pyeloplasty reduce the incidence of febrile UTIs?

PurposeThe use of postoperative prophylactic antibiotics in pediatric upper urinary tract reconstruction remains controversial. In this study, we examined whether low dose antibiotics administered following pediatric pyeloplasty reduce the incidence of febrile urinary tract infections at our institution. As a secondary outcome, in those patients with infection, additional analysis was performed to better quantify which patient population benefits the most from low dose prophylactic antibiotics.MethodsInstitutional review board approval (IRB) was obtained. All methods were carried out in accordance with relevant guidelines and regulations. A retrospective study was performed in patients who underwent pyeloplasty (2011–2017) at our institution. Surgical approach (laparoscopic versus robotic assisted versus open, with or without internal JJ ureteral stent) were based on surgeon preference. Patients of 8 fellowship trained pediatric urologists were included in the study period. Patients with prior history of urologic interventions or other congenital genitourinary tract abnormalities were excluded. Demographics (age, gender, ethnicity, insurance status), prior history of culture proven urinary tract infection, surgical details (administration of perioperative antibiotics), and postoperative outcomes including; 1) re-admission 30 days post-surgery, 2) any urine cultures collected due to suspected urinary tract infection.ResultsA total of 209 patients (149 boys, 60 girls) met our inclusion criteria with 55/209 (26%) receiving postoperative prophylactic antibiotics. The average age was 6 years (range: 2 months-18 years). Indwelling ureteral stent was used in 176 (84%) patients. Eleven patients (5%) had a culture-proven urinary tract infection within 30-days postoperatively. No significant differences were seen in postoperative complications or incidence of urinary tract infection when comparing surgical approaches, +/- ureteral stent, or the use of antibiotics. Secondary analysis noted statistically significant increase in post-operative urinary tract infection in younger children (2.8 v. 6.2 years, p = 0.02), those patients who had a positive preoperative urine culture (8/11, p = 0.01) and those with public health insurance (p = 0.038).ConclusionThe incidence of postoperative urinary tract infection following pyeloplasty in our cohort was relatively low. There was a higher incidence of urinary tract infection in patients less than 3 years old. The use of antibiotics in patients post pyeloplasty did not appear to affect the incidence of post-operative urinary tract infection, however, they may have a role in children who have not yet potty trained and in patients with positive preoperative urine culture.

A novel flexible vacuum-assisted ureteric access sheath in retrograde intrarenal surgery.

A novel flexible vacuum-assisted ureteric access sheath in retrograde intrarenal surgery.

A rare presentation of acute kidney failure due to retroperitoneal fibrosis as a result of gastric linitis plastica: a case-based review

This case study details the experience of a 52-year-old Dutch man, with a 4-month history of epigastric pain and weight loss, who was presented to a urology team and found to have rapidly deteriorating renal function with bilateral hydronephrosis. This prompted his admission to hospital for insertion of bilateral JJ ureteral stents. However, the patient's kidney function continued to worsen despite relief of the obstruction. He became increasingly oliguric and was referred to the renal service. Retroperitoneal fibrosis with acute kidney injury resulting from both obstruction and compression of the urinary system was suspected. Treatment with high-dose steroid was initiated. Shortly after, the patient's urine volume began to increase and his kidney function improved drastically. This avoided the need for dialysis. A month after discharge, the patient was diagnosed with poorly differentiated adenocarcinoma cells of the stomach, a diagnosis consistent with linitis plastica.

A novel tattooing technique for ureteric strictures in robotic ureteroureterostomy: a non-inferiority analysis.

A novel tattooing technique for ureteric strictures in robotic ureteroureterostomy: a non-inferiority analysis.

MO922CASUAL FACTORS AND CLINICAL IMPACT OF URINARY TRACT INFECTIONS IN RENAL TRANSPLANTED PATIENTS: AN OBSERVATIONAL RETROSPECTIVE STUDY*

Abstract Background and Aims Urinary tract infections (UTIs) are the most common infectious disease in kidney transplanted patients (KTxps), especially during the first year of kidney transplantation (KTx). This study aims to examine the etiology of UTIs in a large cohort of KTxps, trying to identify their potential predisposing factors both during the first year and in the global follow-up (FU) of KTx. The impact of UTIs on KTx and patient’s survival in the long term will also be analyzed. Method In our study 585 KTxps (M 343; median age 49 years), out of the 616 KTxps transplanted in our Department between 2004 and 2016, were studied and followed up for a median time of 8 years. Clinical and biochemical data about the 1st (T1) and the 12th month (T12) of KTx were collected. Parameters related to UTIs, defined by a positive urine culture associated with urinary sediment suggestive of UTI, regardless of clinical symptoms, were considered in the global FU. A number of UTIs ≥3 was considered significant during the 1st year of KTx and in the overall FU. The reduction of the eGFR/year of FU, the loss of graft and the death of KTxps with a functioning graft were evaluated as outcome. Results The cohort had a slight prevalence of males (59%) and a median age of 49 years. At the time of KTx, JJ ureteral stent (JJ) was placed in 38% of KTxps, with a median stay time of 47 days. During the FU, 1700 UTIs were found in 458 KTxp, 550 UTIs during the first year of KTx. The pathogens most responsible for UTIs in the global FU were Escherichia coli (61%), Enterococcus (12%) and Klebsiella (8%). According to the number of UTIs found during the 1st year of KTx, KTxp were categorized in: UTI1≥3 (N=139) and UTI1<3 (N=446). UTI1≥3 were more frequently female and older than UTI1<3, had more prevalence of JJ and ATG induction therapy, and had lower hemoglobin and serum albumin at both T1 and T12. The presence of JJ, belonging to the female gender and induction therapy with ATG were the factors most correlated with IVU1≥3 (OR 1.9, 5.3 and 2.1). The studied cohort was also categorized according to the number of UTIs during the global FU in UTItot ≥3 (N=168) and UTItot<3 (N=417). UTI tot ≥3 were more frequently females, older, had a longer dialysis vintage and higher prevalence of JJ placement than UTI tot<3. Furthermore, they had significantly lower hemoglobin and serum albumin values, both at T1 and T12. The presence of JJ, the female gender and age at KTx were the factors most related to UTItot ≥3 (OR 1.8, 5.9 and 1.0). During the FU, the median absolute reduction in eGFR was found to be -0.6[-2.0; +0.9](mL/min)/years. Despite a greater reduction in glomerular filtrate rate in UTI tot≥3 group, the graft loss and the death with functioning graft had no correlation with either UTI1≥3 (7 and 5 patients, respectively) or UTItot≥3 (12 and 8 patients, respectively). Graft loss was observed in 51 KTxps. The number of infections/follow-up time of these KTxps was comparable to that found in those who had a still functioning transplant at the end of observation, and no statistical differences were found in survival analysis according to IVU tot≥3 category. During the global FU, 40 KTxp died with functioning graft. Also with regard to this outcome, no significant correlations were observed with the number of UTIs/follow-up time and in the survival analysis. Conclusion Our data confirm that UTIs are frequent in KTxps. Some factors, such as induction therapy and JJ use, certainly have a favoring effect in UTIs development. Despite the relation observed between UTIs and eGFR reduction, UTIs had no significant impact on graft loss. Beyond prevention through the improvement of lifestyles and various behavioral aspects, the implementation of personalized immunosuppressive protocols associated with a careful management of JJ are desirable interventions in order to prevent the development of UTIs in KTxps.

Outcome of Percutaneous Nephrolithotomy Without JJ Stent in Comparison to Percutaneous Nephrolithotomy With JJ Stent

Objective: This study aims to evaluate the outcomes of PCNL without JJ ureteric stent in comparison to PCNL with JJ ureteric stent. Patients and Methods: This observational study intended to compare the outcome between PCNL without JJ stent and PCNL with JJ stent of 50 cases of renal stone disease according to the inclusion and exclusion criteria and randomly assigned to Group - A (PCNL without JJ stent) and Group - B (PCNL with JJ stent). This study was conducted in the department of urology, Dhaka Medical College Hospital from July 2014 to June 2016. During postoperative period, both groups were compared with respect to fever, loin pain, dysuria, frequency of micturation, duration of haematuria, continuation of urine leakage, hospital stay, urinoma and hematoma and urinary tract infection. Results: Among the 50 patients, the mean postoperative hospital stay was significantly longer in PCNL with JJ stent (4.48 ± 2.14 days) than that of PCNL without JJ stent (2.60 ± 0.50 days). The continuation of urine leakage at the site of percutaneous tract was also significantly longer in PCNL with JJ stent than in PCNL without JJ stent (10.8 ± 3.18 hours vs 14.14 ± 3.28 hours, P <0.001). Assessment of outcome during 3 weeks showed that out of 25 subjects in Group - B, 9 (36%) loin pain, 8 (32%) dysuria, 8 (32%) frequency of micturition, 4 (16%) haematuria and another 7 (28%) urinary tract infection. None of the subjects of Group - A reported same type of complications. Conclusions: Percutaneous Nephrolithotomy without JJ stent (stentless PCNL) is safe, effective and viable option in a selected group of patients – with stone size d”3 cm, normal preoperative renal function, single percutaneous puncture, minimum bleeding, no perforation of the collecting system, no obstruction and complete clearance of stones, JJ stent may not be required. Bangladesh Journal of Urology, Vol. 22, No. 2, July 2019 p.110-117

Percutaneous nephrostomy versus JJ ureteric stent as the initial drainage method in kidney stone patients presenting with acute kidney injury: A prospective randomized study.

To compare percutaneous nephrostomy tube versus JJ stent as an initial urinary drainage procedure in kidney stone patients presenting with acute kidney injury. Between January 2017 and January 2019, 143 patients with acute kidney injury secondary to obstructive kidney stone were prospectively randomized into the percutaneous nephrostomy tube group (71 patients) and JJ stent group (72 patients) at Beni-Suef University Hospital, Beni-Suef, Egypt. Exclusion criteria included candidates for acute dialysis, fever (>38°C), pyonephrosis, pregnancy and uncontrolled coagulopathy. The period required for serum creatinine normalization, failure of insertion, operative and fluoroscopy time were recorded. Definitive stone management for proximal ureteral stones >1.5cm consisted of percutaneous nephrolithotomy for the percutaneous nephrostomy group and ureteroscopic laser lithotripsy for the JJ stent group. For stone size <1.5cm, ureteroscopy or shockwave lithotripsy was carried out for both groups. Percutaneous nephrolithotomy was carried out for renal stones >2cm, and shockwave lithotripsy for stones <2cm. Distal and mid ureteral stones were treated by ureteroscopy. The percutaneous nephrostomy group had shorter operative time (P=0.001). There was no significant difference in the recovery period for normalization of serum creatinine between both groups (P=0.120). Procedural failure, ureteric mucosal injury and perforations increased in the case of male sex, stone size >1.5cm and upper ureteric stones in the JJ stent group. Procedural failure, pelvic perforations and intraoperative bleeding increased in case of male sex, mild hydronephrosis and stone size >2.5cm in the percutaneous nephrostomy group. Suprapubic pain, urethral pain and lower urinary tract symptoms were significant in the JJ stent group. The presence of a JJ stent directed us toward ureteroscopy (P=0.002) and the presence of a percutaneous nephrostomy directed us toward percutaneous nephrolithotomy (P=0.001). Percutaneous nephrostomy facilitates subsequent percutaneous nephrolithotomy, especially when carried out by a urologist, and it has a higher insertion success rate, a shorter operative time and a lesser incidence of postoperative urinary tract infection than a JJ stent. A JJ stent facilitates subsequent ureteroscopy, but operative complications can increase in the case of proximal ureteral stones >1.5cm.

Is peritoneal dialysis prior to kidney transplantation a risk factor for ureteral stenosis after adult to adult live kidney transplantation.

Major urinary complications such as urinary leaks, stenosis or urinary tract infections after kidney transplantation can lead to graft or patient loss. The effect of peritoneal dialysis on post-kidney transplantation complications have been discussed but its effect on ureteral stenosis is unknown. In this study, it was aimed to analyze factors effecting major ureteral complications after living donor kidney transplantation and impact of peritoneal dialysis and double J-stents (JJ stents). This study included 116 adult to adult living donor kidney transplant patients. Factors effecting major urologic complications after living donor kidney transplantation were analyzed. The donors were primary relatives of the recipients. Major urologic complications after living donor kidney transplantation was 8/116 (6.9%). Urinary leak was present in 2 (1.7%) patients. Ureteral stenosis was encountered in 6 (5.2%) patients. Double J stents were used in 84 (72.4%) of the cases. The effect of JJ ureteral stent was not statistically significant for urinary leak, ureteral stenosis (p= 0.074, p= 0.470, respectively). A total of 29 (25%) patients had peritoneal dialysis before kidney transplantation. Preoperative peritoneal dialyses and bacteriuria after kidney transplantation were independent risk factors for ureteral stenosis in multivariate analysis (p= 0.013, and p= 0.010 respectively). In the guidance of the results of the present study, peritoneal dialysis prior to kidney transplantation and bacteriuria are independent risk factors for ureteral stenosis after living donor kidney transplantation. JJ stents have no effect on urologic complications after living donor kidney transplantation.

The safety of ureteral stenting with the use of potassium citrate for management of renal uric acid stones

Objectives:The objective is to evaluate the relative risks of ureteric stents application while managing uric acid stones with potassium citrate in terms of stone encrustations and urinary tract infection (UTI).Patients and Methods:We prospectively enrolled patients with renal uric acid stones who received K citrate from 2013 to 2018. Patient's demographics were collected. All patients were evaluated using noncontrast computed tomography (CT) scan to measure the stone size and density. JJ ureteric stent was inserted prior to the initiation of treatment. At follow-up, all patients underwent urine analysis for pH and to detect UTI. CT was repeated at 1 month and those patients who showed incomplete stone resolution underwent another course of treatment for another month. CT was repeated prior to stent removal. The presence of encrustations was inspected and collected.Results:We collected 59 patients with a median age of 36 years (18–73) and median stone burden of 26 mm3 (15–50). The median stone density was 310 HU (175–498). Twenty-one patients (35.6%) received K citrate treatment for 1-month, while the remaining patients had 2 months treatment. Sixteen patients (27.1%) had a complete stone dissolution, 41 patients (69.5%) had more than 50% decrease of stone burden while only 2 patients (3.4%) had stones with poor dissolution. Four patients (6.8%) experienced UTI while 2 patients (3.4%) had visible JJ encrustations. Most of these complications occurred when the treatment was offered for the 2nd month.Conclusion:Short-term use of ureteral stents is safe during the management of uric acid stones with K citrate.

P113 - Use of HADS (Hospital Anxiety and Depression Scale) as a predictor of JJ ureteral stents’symptoms: A monocentric, prospective experience

P113 - Use of HADS (Hospital Anxiety and Depression Scale) as a predictor of JJ ureteral stents’symptoms: A monocentric, prospective experience

Est-il nécessaire de faire systématiquement un ECBU avant l’ablation d’une sonde double J ?

To assess the value of systematic urine culture before ureteric double j removal. This prospective audit was performed to assess the validity of our current clinical practice. A cohort of informed patients without clinical signs of urinary tract infection and without predefined risk factors were programmed for ureteral double j stent removal in an outpatient setting. Urine was sampled for culture immediately before the procedure. Patients had to complete a self-questionnaire 15 days following stent removal, inquiring about tolerance and complications which were to be analyzed according to the culture results. The primary endpoint was the occurrence of febrile urinary tract infection. Among the 56 participants, immediate preoperative urine culture revealed colonization in 9 patients (16.1%) and contamination in 6 patients (10.7%). A significant association was found between bacteriuria and double j placement following surgery with urinary tract injury (P<0.02) and diabetes (P<0.009). Two patients had fever including a man with sterile urine and a woman with Staphylococcus Aureus infection. No hospitalization was necessary. Twelve patients reported functional signs with lumbar pain being the most common. There was no significant association between functional signs and patients' clinical characteristics. This evaluation was not in favor of modifying our protocol of care i.e. the lack of performing neither antibiotic prophylaxis nor systematic urine culture before JJ ureteral stent removal in a selected population. 4.

Cost awareness in urology: A nationwide survey

Introduction: In the current economic climate with continuous expenditure reviews and financial constraints, clinicians should remain conscious of making cost-effective choices on consumables and medications. In this survey, we evaluated the cost awareness amongst UK urologists. This is an observational study in which urology clinicians were asked to estimate the cost of 10 commonly used medications and consumables in urology by completing a questionnaire. Methodology: The survey was primarily conducted at the BAUS Annual Meeting 2017 with subsequent responders at local hospitals and urological courses. The costs of consumables and medications were verified with the relevant companies and the 73rd edition of the British National Formulary. Result: There were 139 responders from across the UK (46 consultants, 64 training registrars, 13 trust grades doctors and 16 senior house officers (SHOs)). In total, 16 and 60% of all estimates were within ± 25% and ± 100% of the true cost of the items respectively. Approximately 97.1, 95.7 and 97.1% overestimated the cost of a 14Ch urethral catheter, Ciprofloxacin and Sildenafil, respectively; while 78.4 and 84.9% of responders underestimated the cost of a JJ ureteric stent and Solifenacin, respectively. On multivariate analysis, SHOs significantly overestimated the cost of urethral catheters, suprapubic catheterization kits and JJ ureteric stents compared to other clinician grades. Conclusion: Cost awareness among UK urologists is poor. Expensive items (e.g. JJ ureteric stent, Solifenacin) tend to be underestimated while inexpensive items (e.g. catheter, Ciprofloxacin, Sildenafil) tend to be overestimated. This lack of appreciation of value may have an impact on drug and consumable expenditure. Level of Evidence: Level 3

41] Complications of temporary urinary diversion using nephrostomy tube or JJ ureteric stent in pregnant women with symptomatic urolithiasis

ObjectiveTo report the complications of JJ stent and percutaneous nephrostomy (PCN) tube causing hospitalisation of pregnant women, as symptomatic urolithiasis is one of the most important causes of abdominal pain during pregnancy and in some situations it is better to implement temporary treatment and postpone any surgical procedures.

Robotic Pyeloplasty in Children: A "Barbed" Shortcut.

Dismembered pyeloplasty remains the gold standard for the treatment of pelviureteric junction obstruction (PUJO). Robotic approach to this procedure has proven its efficacy and is gaining popularity. The introduction of barbed sutures such as "V-Loc™" (Covidien) has provided an addition to the sutures available for pyeloplasty. This work provides our experience with the V-Loc suture for closure of pelvis in children for robotic pyeloplasty (RP). A review of 10 pediatric RP (da Vinci Robotic System) during which the V-Loc suture was used was performed. Comparison was made with 15 cases in which 5-0 Vicryl® suture was used as an alternative. Overall median age was 4 (range 9 months to 16 years), M:F = 14:9. All had confirmed PUJO on renal ultrasound and mercaptoacetyltriglycine (mertiatide) (MAG-3). RP was done in the standard Anderson-Hynes manner with the placement of a multilength JJ ureteral stent intraoperatively. Patients had removal of the JJ stent 6 weeks postoperatively followed by renal ultrasound 3-4 months later. Twenty-five RPs have been performed between May 2013 and November 2015, of which 10 have had closure of the pelvis performed using the V-Loc suture and 15 with Vicryl. One patient (6.67%) in the Vicryl group underwent redo-pyeloplasty secondary to a stent-related complication. The entire V-Loc group made an eventful initial recovery; however, four (40%) developed worsening hydronephrosis and drainage on ultrasound and MAG-3 after stent removal, despite remaining completely asymptomatic. These four required either restenting and observation (n = 1) or redo-pyeloplasty (n = 3). Histology demonstrated a "plaque-like" inflammatory reaction at the pelvic suture line. Closure of the pelvis using V-Loc suture material during RP can lead to a significant hydronephrosis requiring further procedures, including redo-pyeloplasty. These children can be asymptomatic and so extra vigilance on postoperative follow-up is essential.

Is confirmation of ureteric stent placement in laparoscopic pyeloplasty necessary?

Placement of an antegrade double-J (JJ) ureteric stent is an important component of pyeloplasty. Correct siting of distal end of the stent in the bladder is essential for ease of removal. To date, no studies have compared methods for confirming stent position. This study aims to address that void in the literature. Eligible patients underwent laparoscopic pyeloplasty with antegrade stent placement at our institution from 2007 to 2015 inclusive. Methods to verify distal stent position of rigid cystoscopy, artificial bladder filling or no confirmation were compared. Effectiveness was determined by the proportion of malpositioned stents detected intra-operatively compared to the total found malpositioned, both intra-operatively and during follow-up. A total of 75 patients underwent laparoscopic pyeloplasty. Forty-six (61.3%) patients had distal stent position assessed intra-operatively, comprising 27 by cystoscopy and 19 by artificial bladder filling, while for 29 (38.7%) patients no verification method was used. Cystoscopy, artificial bladder filling and no confirmation detected intra-operatively 2, 1 and 0 malpositioned stents, from malpositioned stent totals of 2, 2 and 1, respectively. Malposition of JJ ureteric stent is uncommon, and omitting intra-operative position verification appears reasonable in select cases. Artificial bladder filling can help detect malpositioned JJ stents without repositioning the patient for cystoscopy. However, our results suggest both may be unreliable. If stent malposition is suspected, certainty is desired or extended operative duration is less critical, then the surgeon should proceed with cystoscopy.

PD19-05 THE OPTIMAL GUIDEWIRE TYPE AND EFFECT OF PRIOR USE ON THE EASE OF URETERAL STENT INSERTION

INTRODUCTION AND OBJECTIVES: Ureteral stent insertion is a frequent procedure in endourology, with no clear consensus on the best wire type to facilitate stent insertion. Use of wires may result in deterioration of their protective coating, requiring greater force for stent insertion. The purpose of this study was to identify the effect of wire type, and prior use, upon average insertion force needed for a 6Fr ureteral stent. METHODS: Stent insertion was tested using an ex vivo porcine urinary tract model with continuous water infusion (1cc/min) to simulate urine production. For each trial, a new, soft, 6Fr Cook JJ ureteral stent was advanced over new and used 0.03800 diameter guide wires including the Glidewire (Terumo), Standard Teflon-coated wire (Cook), Superstiff wire (Cook), Sensor wire (Boston Scientific), Zip-wire (Boston Scientific), and Zebra wire (Boston Scientific). A Mark-10 digital force gauge was attached to the stent, and at a constant advancing rate of 2 rotations per second, the forces to advance the stent over the wire were calculated. 10 trials of stent insertion were randomly performed on 12 new and 12 used guide wires (total of 240 placements). RESULTS: The new Glidewire had the lowest average force required for stent advancement (0.18N). The forces for insertion of all other new wires were significantly higher; Standard (1.25N; p<0.01), Superstiff (2.03N; p<0.01), Sensor (1.87; p<0.01), Zip (0.22N; p<0.01), and Zebra (0.61; p<0.01). When comparing the average insertion force between new and used wires, the used wires required greater mean force in the Standard (2.42N vs. 1.25N; p <0.01), Superstiff (2.68N vs. 2.03N; p <0.01), and Zipwire (0.36N vs. 0.22N; p <.01), but there was no statistical difference between used and new fibers in the Glidewire (0.28N vs. 0.18N; p1⁄40.14), Sensor ( 1.66N vs. 1.87N; p1⁄40.18) and Zebra wire (0.59N vs.0.61N; p1⁄40.67). CONCLUSIONS: The Glidewire resulted in the lowest force for ureteral stent insertion. It may be used several times with no significant effect on ureteral stent insertion force due its resilient lubricious hydrophilic coating. Employing a used Standard, Superstiff and Zip-wire may result in additional stent insertion force. Knowledge of the forces required for stent insertion over various guide wires may allow surgeons to improve the ease and safety of stent placement.

Preliminary Assessment of a New Antireflux Ureteral Stent Design in Swine Model

To assess a new antireflux ureteral stent in animal model. The design expects to reduce morbidity associated with JJ ureteral stents. Twelve pigs were used in this study. The study began with a nephrosonographic assessment and excretory urography. Afterward, measurement of the internal diameter of both ureteropelvic junctions (UPJ) by retrograde ureteropyelography was performed. A 3 Fr (ARS group) antireflux ureteral stent was placed in the right kidney and a JJ 4 Fr (JJ group) stent was placed in the left. Follow-ups were performed at 3-6weeks; both stents were removed at 6weeks. The final follow-up was completed at 5months. This includes the above-mentioned diagnostic methods and an anatomopathological study. There were no significant differences in UPJ diameter evolution between groups. During renal damage assessment, significant differences at 3 and 6weeks were found, renal dilation being larger in JJ group. The JJ group shows a higher degree of vesicoureteral reflux at 3 and 6weeks. After assessment of ureteral orifice, significant differences between groups were found at 3weeks, 6weeks, and 5months, damage being more severe in the JJ group. After anatomopathological assessment, no statistical significance at UPJ was observed. However, statistical significance was found at ureterovesical junction, damage being more severe in the JJ group. The antireflux ureteral stent design dilates the upper urinary tract without affecting ureterovesical junction, and consequently reduces morbidity associated with JJ ureteral stents. Therefore, its patient tolerance will possibly be better than that to existent designs.

Forgotten JJ stent: A rare case report

Indications for stent insertion have increased in recent years since their introduction in 1978; along with increase in their use and hence their complications. JJ ureteral stents are commonly placed for short term for prevention or relief of upper urinary tract obstruction and following reconstructive surgery. Long stay of JJ stents in the body causes undesired side effects. The forgotten stents can produce considerable morbidity and mortality.