Removal of Partially Deployed Supera Stents: Case-Based Review and Technical Considerations

Purpose: Maldeployment of the Supera stent system can result in primary technical failure, inferior primary patency, and poorer patient outcomes. The purpose of this article is to present a case series illustrating the conditions required to perform optimal stent deployment, and if necessary, undertake successful stent removal following maldeployment. Technique: Two key failures of effective Supera deployment are elongation and invagination. Several technical factors should be considered to reduce the risk of maldeployment: aggressive target vessel predilation, the use of multiple fluoroscopic views, slow deployment with controlled forward pressure applied on the delivery device, “sandwich packing” of the stent above and below target lesions, and the “pulling back” of invagination. To successfully retrieve a partially deployed stent, 3 factors should be considered: the percentage of the stent already deployed, the distance from the distal tip of the introducing sheath to the proximal extent of the deployed stent, and the severity of proximal vessel disease. The higher these factors, the greater the risk of stent detachment and failed retrieval. Conclusion: In this series of 6 cases of maldeployment, the removal of a partially deployed Supera stent appeared to be feasible and safe, with success dependent on selected technical and anatomical considerations.

Innovation and new technology in ureteral stents

Ureteral stent insertion is a procedure performed extensively by all urologists. Nevertheless, stent-related symptoms and stent encrustation are still common complications pushing the innovation and development of novel ureteral stents. Developments are focussing on three significant aspects: material, design, and removal technique. Various materials including silicone, polymers, and metals are frequently utilized, with or without an additional coating. The use of biodegradable materials is looking promising but these is a lack of proven clinical trials in association with this in humans. The new designs focus on the reduction of stent-related symptoms through the modification of the bladder end. The new stent removal techniques with extraction strings or novel magnetic end may exclude subsequent cystoscopic procedures. Finally, utilization of a ureteral stent tracker application helps in reminding both physicians and patients to remove the stent at the appropriate time.

P-P25 Hot Axios stent removal following endoscopic pancreatic necrosectomy

Background Symptomatic pancreatic pseudocysts or walled off necrosis following pancreatitis can be drained via a stoma from the collection to the GI tract, this is typically facilitated by endoscopic stents. These stents are left in-situ until the area has drained, this can take several months. The stent is then ideally removed endoscopically. Little is known about the consequences of failed endoscopic stent removal or factors contributing to this failure. Methods Retrospective analysis of prospective data at LUHFT between 1st January 2018 and 31st December 2019 of patients receiving at least one Hot Axios stent for management of pancreatic collection. Normally distributed data were compared using Student’s two tailed T test, with non-parametric data compared using Mann-Witney U test, categorical data were analysed using Chi2 test Results 131 patients were included in analysis, of which 74 were male with a median age of 56 years (IQR 46-66.5). Failure of endoscopic removal (14 patients) was associated with a longer time to removal; 101 days (IQR 78-121) to first attempt vs. 49 days (IQR 19-104) to first endoscopic attempt where the stent was successfully retrieved endoscopically (p < 0.01). Surgical removal was undertaken in 6 patients, with significant morbidity in 2 of 6 patients. Overall 90-day mortality in patients undergoing Hot Axios stent placement was 8 of 131 (6%). Conclusions Endoscopic stent removal fails more frequently in patients where the stent has remained in situ for a long time before removal is attempted. Surgical removal of Hot Axios Stents is associated with significant morbidity, and this should be balanced against the as yet unknown consequences of leaving Hot Axios stent in-situ permanently.

Stent encrustation or fragmentation? A case report of post stent removal encrustation in postpartum woman and literature review

Background Ureteral stents are commonly used in the field of urology to relieve ureteral obstruction. However, complications relating to ureteral stent use, such as encrustation continue to occur, especially with prolonged indwell time. Case presentation Here we present a 37-year-old postpartum woman with a foreign body in her bladder after removing a ureteral stent 1 month before. She insisted that the foreign body was the fragment of stent and asked for medical malpractice indemnity payments while the surgeon of her insisted that the stent was intact during the procedure. Finally, the foreign body was confirmed as an encrustation by cystoscopy and the patient received 10,000 yuan ($ 1500) as indemnity payments after encrustation removal. Conclusion In the absence of guidelines, stent indwelling time vary with centers’ habits, stent materials and patient’s education. Early detection of stent encrustation and timely removal of the encrusted stent are still the best way to avoid stent retention. Violent stent removal is of danger and not recommended in any case.

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 (Lstring), which was shortened to 4 cm (cm) past the urethral meatus; 108 patients (Novel-S group) underwent the novel method (Lstring = Lurethra + 2 cm), the length of urethra (Lurethra) 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.