Developing a preoperative predictive model for ureteral length for ureteral stent insertion

Migration of double-J ureteral stent in patients with ureteroileal anastomosis stricture undergoing radical cystectomy and orthotopic neobladder: Analysis risk factors of stent migration

The objective was to evaluate the incidence and degree of double-J ureteral stent (DJUS) migration. Additionally, we aimed to investigate the risk factors associated with stent migration in the orthotopic neobladder group. In this retrospective study, 61 consecutive patients were included; 35 patients (45 DJUS placements) underwent radical cystectomy with orthotopic neobladder and 26 patients (35 DJUS placements) underwent urinary bladder without cystectomy between July 2021 and March 2023. All the patients were treated with a DJUS for ureteric strictures. The technical success rate was 100% in each group. The DJUS migration was significantly higher in the orthotopic neobladder group, with 22 of 45 cases (48.9%), compared to the urinary bladder group, which had 4 of 35 cases (11.4%) (P ≤ .001). Among the patients in the orthotopic neobladder group who experienced DJUS migration, stent dysfunction occurred in 18 cases (81.8%), which was statistically significant (P = .003). Multivariate logistic regression analysis revealed that only the size of the DJUS was significantly and positively associated with migration (odds ratio:10.214, P = .010). DJUS migration can easily occur in patients undergoing radical cystectomy and orthotopic neobladder, and smaller stent sizes are associated with a higher incidence of migration.

Lower urinary tract effects of ureteral stent length and intravesical position

PURPOSE

Ureteral stents can cause lower urinary tract problems such as stent-related irritative symptoms and urinary tract infections. This study aimed to determine the lower urinary tract effects of ureteral stent length and intravesical position in children.

METHODS

Patients who underwent double-J stenting after urological procedures between January 2017 and January 2022 were included in the study. The patients were assessed in terms of age, irritative symptoms, urinary tract infections, and stent length. The intravesical position of the ureteral stents was grouped as cross-trigonal and ipsilateral. The distribution of irritative symptoms, frequency of urinary tract infections and stent length were analyzed according to intravesical location.

RESULTS

A total of 47 patients were included in the study. The median age was 5 years (range: 1-16). Cross-trigonal stent position was significantly associated with symptoms of urgency (p = 0.046), suprapubic pain (p = 0.002), and lower mean age (p = 0.004). Urinary tract infections were more frequent in patients whose placed stents were longer than recommended (p < 0.001) or were in cross-trigonal position (p = 0.043).

CONCLUSION

Our results suggest that stent-related irritative symptoms and urinary tract infections can be reduced in pediatric patients using a suitably sized ureteral stent and considering its intravesical position.

Comparison of external stents and DJ stents techniques for pediatric pyeloplasty: A systematic review and meta-analysis

OBJECTIVE

To evaluate and compare the efficacy and safety between an external stent and a Double J stent for pediatric Pyeloplasty.

METHODS

Through a systematical search of multiple scientific databases in July 2022, we performed a systematic review and meta-analysis of the primary outcomes of interest according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses), whose protocol was registered with PROSPERO(CRD42021274087).

RESULTS

Eleven studies involving 1,758 patients were included. No significant differences were observed in operative time (MD: 2.26; 95% CI -9.62 to 14.14; P = 0.79), operative success rate (OR: 1.10; 95% CI 0.57 to 2.10; P = 0.780), length of hospital stay (MD: 0.65; 95% CI -0.04 to 1.34; P = 0.063), or complications (OR: 0.87; 95%CI 0.48 to 1.56; P = 0.630) between external stents and DJ stents in pediatric pyeloplasty. According to the subgroup analysis, we found the external stent group had a shorter operative time than the DJ stent group in terms of robot-assisted laparoscopic pyeloplasty (MD: -17.13; 95% CI -32.8 to -1.45; P = 0.032).

CONCLUSIONS

There were no significant differences in operative time, operative success rate, length of hospital stay, or complications between external stents and DJ stents in pediatric pyeloplasty. The external stented procedure seemed to have less operative time when using robot-assisted laparoscopic pyeloplasty. However, due to the limitations of our analysis, more studies are still required to support our conclusion.

SYSTEMATIC REVIEW REGISTRATION

This systematic review has been registered on PROSPERO, the registration ID is CRD42021274087.

New Stent Technologies

Ureteral stents are an indispensable part of any (endo-) urologic practice. Despite the widely demonstrated advantages of stents, they also carry a considerable risk of side effects and complications, such as urinary symptoms, pain, hematuria, decreased quality of life, stent-related infection, and encrustation. Multiple pathways in preventing or mitigating these side effects and complications and improving stent efficacy have been and are being investigated, including stent architecture and design, biomaterials, and coatings. This article provides an update on currently researched and available stents as well as future perspectives.

Proximal migration of a 'double J' ureteric stent in a patient with a staghorn calculus

Ureteric stents are widely used for the management of obstructive uropathy and intraoperative identification of the ureters. Despite undergoing numerous modifications since their introduction in 1967, they are frequently associated with complications ranging from irritative symptoms to migration of the stent. Proximal migration of ureteric stents is a relatively uncommon occurrence, with a reported incidence of 1–4.2%; it is usually associated with inappropriate stent length, poor positioning or incorrect deployment of the stent. Here we discuss an interesting case of a patient who unfortunately suffered proximal ureteric stent migration associated with pelvico-ureteric junction obstruction, despite appropriate stent choice, adequate deployment and confirmation of correct positioning. This complication likely occurred secondary to mechanical disruption of the stent caused by the presence of a large staghorn calculus within the renal pelvis.

[Is the ureteral length associated with the patient's size?]

OBJECTIVE

To assess the relation between the ureteral length and the patients' size.

PATIENTS AND METHOD

Prospective study made between September 2012 and May 2014, on 87 patients with 42 men and 45 women, in whom the ureteral measure was performed during the various procedures that require the use of a pigtail stent. The average age of the population was 53 years old (±15.9) with an average height of 168.3cm (±8.4). This has been achieved through ureteral catheter combining fluoroscopy and endoscopy.

RESULTS

The ureteral average length was 23.5cm (±2.33). The ureteral average length was 23.8cm (±2.18) for man and 23.2cm (±2.44) for women. In this population, there were a positive correlation between the size of the patients and the length of the ureters (r=0.75; P=0.01). However, this correlation was not found in all subgroups, particularly among women (r=0.16; P=0.30) and on the right side of men (r=0.34; P=0.12). This correlation was still true for the left side in the men's group (r=0.50; P=0.02).

CONCLUSION

In this study, there is a positive correlation between the patients' size and the ureteral length. But this correlation is not found in some subgroups. It is better to perform in vivo the ureteral measurement to have the precise length in order to set up a pigtail stent adapted to the patient.

LEVEL OF EVIDENCE

3.

Biodegradation behavior of magnesium and ZK60 alloy in artificial urine and rat models

In this work, the biodegradable and histocompatibility properties of pure Mg and ZK60 alloy were investigated as new temporary implants for urinary applications. The corrosion mechanism in artificial urine was proposed using electrochemical impedance spectroscopy and potentiodynamic polarization tests. The corrosion potential of pure magnesium and ZK60 alloy were −1820 and −1561 mV, respectively, and the corrosion current densities were 59.66 ± 6.41 and 41.94 ± 0.53 μA cm⁻², respectively. The in vitro degradation rates for pure Mg and ZK60 alloy in artificial urine were 0.382 and 1.023 mm/y, respectively, determined from immersion tests. The ZK60 alloy degraded faster than the pure Mg in both artificial urine and in rat bladders (the implants of both samples are ø 3 mm × 5 mm). Histocompatibility evaluations showed good histocompatibility for the pure Mg and ZK60 alloy during the 3 weeks post-implantation in rat bladders, and no harm was observed in the bladder, liver and kidney tissues. The results provide key information on the degradation properties and corrosion mechanism of pure Mg and ZK60 alloy in the urinary system.

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ZK60 obtained loose corrosion product layer with poor corrosion resistance in AU.

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ZK60 showed a faster degradation rate than Mg in artificial urine and bladder of rat.

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Mg and ZK60 alloy showed good histocompatibility for the bladder model of rat.