Future developments in ureteral stents

Noncystoscopic Removal of Double-J Stent in Women: Feasibility and Safety

OBJECTIVE

To evaluate the feasibility and safety of a simple noncystoscopic method previously applied in children for removing double-J stents applied in women by comparing the hospitalization time, operation time, costs, complications, and success rate.

METHODS

One hundred eighty women who underwent either cystoscopic or noncystoscopic double-J stent removal in a randomized manner. They were randomly assigned 1:1 to groups of cystoscopic double-J stent removal (n = 90) or noncystoscopic double-J stent removal (n = 90). The age ranged from 19 to 72years. After the removal of the double-J stent, the operation time, costs, complications, and success rate were compared between the two groups.

RESULTS

The operation time of the noncystoscopic group was lower than that of the cystoscopic group (6.0(5.0,7.0) minutes vs 2.0(2.0,3.0) minutes, P < .001). The hospitalization costs of the noncystoscopic group were significantly shorter than that of the cystoscopic group (1361.2(1331.4,1379.2) Yuan vs 873.9(868.5,896.1) Yuan, P < .001). There were no complications such as infection and massive bleeding in the two groups during and after the operation. Most noncystoscopic double-J stent removal can succeed in less than three attempts (88/90). All patients in the noncystoscopic group used this technique to remove the double-J stent.

CONCLUSION

Noncystoscopic removal of double-J stent has the advantages of short operation time and low hospitalization costs. It is a safe and feasible minimally invasive method to replace cystoscopic removal of the double-J stent.

Antistricture Ureteral Stents with a Braided Composite Structure and Surface Modification with Antistenosis Drugs

The present work describes the development of a drug-loaded ureteral stent with antistricture function based on a trilayer design in which the middle layer was braided from biodegradable poly(p-dioxanone) (PDO) monofilament. Antistenosis drugs rapamycin and paclitaxel were loaded into a silk fibroin (SF) solution and coated on the inner and outer layers of the braided PDO stent. The cumulative release of rapamycin and paclitaxel was sustained over 30 days, with a total release above 80%. The drug-loaded ureteral stents inhibited the proliferation of fibroblasts and smooth muscle cells in vitro. Subcutaneous implantation in rats showed that the drug-loaded ureteral stents were biocompatible with durable mechanical properties in vivo, revealing the inhibition of an excessive growth of fibroblasts and excessive deposition of collagen fibers. In conclusion, the dual-drug-loaded biodegradable ureteral stents show the possibility for treatment of ureteral strictures and avoid the occurrence of complications such as inflammation and restricture.

Comparation of intraureteral stent and conventional stent at different stages: a systematic review with meta-analysis

INTRODUCTION

Stent related symptom (SRS) is the most common adverse effect of ureteral stenting. In recent years, many efforts have been made to develope modified ureteral stents to ameliorate SRS. It has been reported that intraureteral stents have the potential to improve the tail end adverse effect of the bladder and alleviate SRS. However, there still lack of evidence for the efficacy and the safety of clinically applying intraureteral stents. The aim of this work is to investigate the efficacy and safety of intraureteral stents.

EVIDENCE ACQUISITION

A systematic review was performed by using the PubMed, Web of Science, Medline, Embase, and Cochrane library. The studies published before February 2023 were included. The study selection was following the guideline from Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). The searching strategy was: "Pigtail suture stent" OR "Intra-ureteric stent" OR "Suture Stent" OR "Intraureteral stent" AND "Ureteroscopy" OR "Urinary calculi" OR "Stent-related symptoms" OR "Lower urinary tract symptoms". The data from randomized clinical trials which meet the selection criteria were extracted. Revman 5.4 was employed to proceed the meta-analysis.

EVIDENCE SYNTHESIS

A total of six randomized clinical trials of intraureteral stents were included in this systematic review and meta-analysis. According to the different investigation time, the results could be divided into four stages: early-stage, middle-stage, late-stage, and long-term evaluation. Urinary symptoms, pain score, and general health were significantly improved in intraureteral stents group at middle stage. For late-stage, intraureteral stent achieved better outcomes in urinary symptoms index, VAS score, quality of life, general health, and pain score. However, for early-stage and long-term evaluation, there was no significant difference between two groups.

CONCLUSIONS

This systematic review and meta-analysis reveal that regardless of the stage of treatment, the efficacy and safety of intraureteral stent are no worse than that of conventional stent. During 7-14 days postoperation, which is the most commonly time for clinically using ureteral stent, most of the outcomes of intraureteral stent are better than those of conventional stent. Hence, it is confirmed that intraureteral stent is worth for more clinical study and application.

Incidental findings on prostate MRI: a close look at the field of view in this anatomical region

Magnetic resonance imaging (MRI) has been widely used as an advanced imaging modality to detect prostate cancer and indicate suspicious areas to guide biopsy procedures. The increasing number of prostate examinations with MRI has provided an opportunity to detect incidental lesions, and some might be very significant to elucidate patient symptoms or occult neoplastic process in the early stages. These incidental lesions might be located in the prostate gland, adjacent tissues, or organs around the prostate gland or out of the genitourinary system. The field of view of prostate MRI includes not only the prostate gland but also other critical pelvic organs in this specific anatomical region. Some of these incidental lesions might cause the same symptoms as prostate cancer and might explain the symptoms of the patient, and some might indicate early cancer stages located outside the prostate. Reporting these lesions might be life-saving by initiating early disease treatment. Awareness of the predicted locations of congenital anomalies would also be beneficial for the radiologists to mention these incidental findings.

Novel method to decrease the exposure time of the extraction string of the ureteral stent and its efficiency and safety verification in the clinic

Ureteral stent removal by an extraction string is advantageous. However, the increased risk of complications attributed to the continuous exposure of the string outside the urethra must be managed. This paper introduces a method to decrease the exposure time, and conducts a retrospective study to verify its efficiency and safety. A total of 231 male patients undergoing routine ureteroscopy (URS) were included, and all of them accepted indwelling ureteral stents with strings. Among them, 123 patients (Normal-S group) underwent the normal method to determine the length of string (L_string), which was shortened to 4 cm (cm) past the urethral meatus; 108 patients (Novel-S group) underwent the novel method (L_string = L_urethra + 2 cm), the length of urethra (L_urethra) was measured during ureteroscopy by ureteroscope body. The demographic characteristics, stent indwelling and removal-related variables, complications, and medical costs in each group were recorded. There was no significant difference in demographic characteristics, the rate of UTI, the operative duration of URS, or the VAS pain scores for stent removal between the 2 groups. For the Novel-S group, the stent dwelling time was longer, the self-rated discomfort and symptom, the stent dislodgement rate, the numbers of clinic or emergency visits and the overall medical cost post operation was lower in comparison with the Normal-S group, while the rate of removal of stents by hand was lower, the time for removing ureteral stents was longer. This novel method improved stenting comfort, avoided ureteral stent dislodgement, decreased complications, and lowered medical costs, it was safe and reliable and merits widespread application.

A randomized trial investigating clinical outcomes and stent-related symptoms after placement of a complete intra-ureteric stent on a string versus conventional stent placement

OBJECTIVE

To compare stent-related symptoms (SRS) associated with conventional ureteric JJ stent (CUS) placement and SRS associated with placement of a modified complete intra-ureteric stent (CIUS) with extraction suture, designed to minimize SRS, using the validated Ureteral Stent Symptom Questionnaire (USSQ).

MATERIALS AND METHODS

We randomized 124 patients who had undergone uncomplicated ureteroscopic lithotripsy into a CIUS and a CUS placement group. USSQ scores were evaluated on postoperative days 1 and 7 (just before stent removal) and 4 weeks after stent removal (control values). Pain scores on a visual analogue scale (VAS) after stent removal were also recorded. Subdomain analysis of all SRS and stent-related complications were also compared.

RESULTS

No significant intergroup differences were found in the domain scores for urinary symptoms (P = 0.74), pain (P = 0.32), general health (P = 0.27), work (P = 0.24), or additional problems (P = 0.29). However, a statistically significant difference was noted in VAS scores (P = 0.015). Analysis of subdomains of USSQ item scores showed the CIUS group had significantly better scores for urge incontinence (1.21 vs 1.00; P ≤ 0.001), discomfort on voiding (2.07 vs 1.50; P ≤ 0.001), difficulties with respect to light physical activity (1.131 vs 1.00; P ≤ 0.001), fatigue (1.84 vs 1.57; P = 0.002), feeling comfortable (3.68 vs 3.16; P = 0.003), need for extra help (1.96 vs 1.00; P ≤ 0.001), and change in duration of work (4.27 vs 1.86; P ≤ 0.001). However, the patients in the CIUS group were sexually inactive for the time during which the stent was indwelling (mean: 7.34 days). There was no difference in complication rates between the two groups.

CONCLUSION

The use of a CIUS with strings after Ureteroscopy decreases SRS.

Feasibility and Safety of a Simple Non-cystoscopic Double-J Tube Removal Technique in Children

Objective: Double-J tube placement is an important procedure during upper urinary tract surgery. A primary drawback is the requirement of a second double-J tube removal under a cystoscope. Therefore, a simple and feasible alternative is required to remove the double-J tube without cystoscopy. The present study reported the feasibility and safety of a simple non-cystoscopic double-J tube removal technique. Method: We retrospectively analysed children who underwent pyeloplasty and ureterovesical reimplantation between June 2015 and August 2021. A simple device (a catheter with a suture) was used to pull out the double-J tube. Patient characteristics, detailed surgical procedures, success and complication rates and reasons for failure were evaluated. Result: A total of 613 children were included. The mean age of patients was 6.2 months (3 months-14 years). Non-endoscopic methods were used to remove the double-J tube in all except 6 patients (0.9%). Of the 6 patients who required ureteroscopy or cystoscopy, 4 had retraction of the double-J tube into the ureter, and 2 (0.6%) had bladder stones. Of the 613 patients, 479 (76.0%) required one attempt, 127 (20.1%) required two attempts and 19 (3.0%) required several attempts. No serious postoperative complications occurred in all patients. The most common complications were gross haematuria (22.5%), pain urinating (17.9%), difficulty in urinating (3.6%), foreskin injury (1.7%), and penile oedema (1.3%). No urethral strictures developed during the follow-up period. Conclusion: The study results demonstrated that the modified and simple non-cystoscopic double-J tube removal technique is a safe and an effective alternative to cystoscopy in clinical practise.

Drug-Eluting Stents and Balloons-Materials, Structure Designs, and Coating Techniques: A Review

Controlled drug delivery is a matter of interest to numerous scientists from various domains, as well as an essential issue for society as a whole. In the treatment of many diseases, it is crucial to control the dosing of a drug for a long time and thus maintain its optimal concentration in the tissue. Heart diseases are particularly important in this aspect. One such disease is an obstructive arterial disease affecting millions of people around the world. In recent years, stents and balloon catheters have reached a significant position in the treatment of this condition. Balloon catheters are also successfully used to manage tear ducts, paranasal sinuses, or salivary glands disorders. Modern technology is continually striving to improve the results of previous generations of stents and balloon catheters by refining their design, structure, and constituent materials. These advances result in the development of both successive models of drug-eluting stents (DES) and drug-eluting balloons (DEB). This paper presents milestones in the development of DES and DEB, which are a significant option in the treatment of coronary artery diseases. This report reviews the works related to achievements in construction designs and materials, as well as preparation technologies, of DES and DEB. Special attention was paid to the polymeric biodegradable materials used in the production of the above-mentioned devices. Information was also collected on the various methods of producing drug release coatings and their effectiveness in releasing the active substance.

Clinical Effectiveness of Single Pigtail Suture Stent on Patient Comfort: A Double-Blind Prospective Randomized Trial

Background: A double-pigtail ureteral stent (DPUS) can cause untoward symptoms, such as urgency, frequency, urinary incontinence, hematuria, and body pain that are bothersome to patient's quality of life (QoL). By reducing the quantity of material in the bladder, it could be reasonable to decrease stent-related symptoms (SRSs). We aimed to evaluate the tolerability of single pigtail suture stent (SPSS) with a validated questionnaire after uncomplicated retrograde semirigid ureteroscopic lithotripsy (URSL). Materials and Methods: A total of 130 patients who underwent ureteral stent placement after URSL for unilateral symptomatic ureteral stones with <15 mm diameter were randomized prospectively into two groups. Polyurethane ureteral stent (6 Fr, 24 or 26 cm) was placed in all patients, which was removed postoperatively with a mean of 14 days. There were 65 patients in both groups. All subjects completed the ureteral stent symptoms questionnaire (USSQ), which explores the SRSs. The questionnaires were conducted on the day of stent removal (at week 2) with the stent in situ and 4 weeks after removal (at week 6, poststent). The severity of SRSs and QoL were compared between the two groups. Results: SPSS was associated with perfect effect on all domains of USSQ, except from sexual and general health index scores. Pain index scores, visual analog scores (VAS), and analgesic requirements in SPSS group were found significantly low compared with those in the DPUS group. The QoL scores were significantly better in patients indwelling SPSS. Conclusion: SPSS is a potentially beneficial option to minimize ureteral SRSs after uncomplicated URSL.