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.

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Outcomes of Ureteral Stent Placement for Hydronephrosis in Patients with Gynecological Malignancies

Current Urology ◽

10.1159/000447165 ◽

2016 ◽

Vol 10 (3) ◽

pp. 126-131 ◽

Cited By ~ 2

Author(s):

Saya Kurata ◽

Shohei Tobu ◽

Kazuma Udo ◽

Mitsuru Noguchi

Keyword(s):

Radiation Therapy ◽

Stent Placement ◽

Poor Prognosis ◽

Ureteral Stent ◽

Ureteral Stents ◽

Ureteral Stenosis ◽

Stent Removal ◽

Gynecological Malignancies ◽

Lymph Node Swelling ◽

Observation Period

Objective: We examined the outcomes of patients undergoing ureteral stent placement for hydronephrosis that occurred during treatment for gynecological malignancies. Materials and Methods: From January 2004 to December 2009, we enrolled 33 patients with 45 ureters undergoing ureteral stent placement for hydronephrosis which occurred during treatment for gynecological malignancies. We examined the outcomes of the patients after stent placement. Results: The causes of hydronephrosis were obstruction of the urinary tract by a tumor (n = 22), obstruction due to lymph node swelling (n = 6), ureteral stenosis after radiation therapy (n = 4), and others (n = 1). The ureteral stent was inserted into both ureters in 12 cases, and into one ureter in 21 cases. Ureteral stents were replaced 1-26 times during the observation period (median 3 times). Eighteen (40%) ureteral stents were removed. The reasons for ureteral stent removal were hydronephrosis improvement (11 ureters, 24.4%), a change to nephrostomy (cystectomy: 1 ureter, progression of ureteral stenosis: 2 ureters), renal atrophy (3 ureters), and ureteral dilatation (1 ureter). All of the cases in which ureteral stent withdrawal due to hydronephrosis improvement were cases in which the ureter was compressed by a tumor and were lower ureteral obstructions. Twenty-one patients (64%) died due to cancer after stent placement. The periods from the first stent placement to death ranged from 1 to 58 months (median 18 months). Conclusion: Ureteral stent placement was associated with a poor prognosis in patients with gynecological malignancies. There were a few cases in which stent withdrawal became possible due to the improvement of hydronephrosis. In such cases, the withdrawal rate varied according to the cause and obstructive level.

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

Scientific Reports ◽

10.1038/s41598-021-01821-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

WenGang Hu ◽

YaJun Song ◽

Yang Li ◽

YueHua Li ◽

Jiao Mu ◽

...

Keyword(s):

Exposure Time ◽

Medical Costs ◽

Demographic Characteristics ◽

Ureteral Stent ◽

Continuous Exposure ◽

The Novel ◽

Ureteral Stents ◽

Stent Removal ◽

Significant Difference ◽

Novel Method

AbstractUreteral 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.

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

BMC Pregnancy and Childbirth ◽

10.1186/s12884-021-04262-x ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Zhaohua Ye ◽

Qiwu Mi ◽

Renzhao Huang

Keyword(s):

Case Report ◽

Foreign Body ◽

Literature Review ◽

Medical Malpractice ◽

Ureteral Stent ◽

Postpartum Woman ◽

Ureteral Stents ◽

Case Presentation ◽

Stent Removal ◽

Indwelling Time

Abstract 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.

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Bilateral Encrusted Metallic Stent Successfully Removed by Ureteroscopic Lithotripsy Using a Ho:YAG Laser in a Patient with Malignant Myeloma

Case Reports in Oncology ◽

10.1159/000511601 ◽

2020 ◽

Vol 13 (3) ◽

pp. 1501-1505

Author(s):

Takahiro Hanai ◽

Takashi Kawahara ◽

Hiroaki Ishida ◽

Shinnosuke Kuroda ◽

Toshitaka Miyai ◽

...

Keyword(s):

Laser Lithotripsy ◽

Ureteral Stent ◽

Stent Insertion ◽

Metallic Stent ◽

Ureteral Stents ◽

Ureteroscopic Lithotripsy ◽

Ho:Yag Laser ◽

Malignant Ureteral Obstruction ◽

Stent Exchange ◽

Endoscopic Lithotripsy

Ureteral stent encrustation is sometimes encountered, especially in cases in which a ureteral stent has been forgotten. An 84-year-old female patient with malignant myeloma underwent metallic ureteral stent insertion to treat malignant ureteral obstruction. At the time of scheduled ureteral stent exchange, the stent was heavily encrusted and could not be removed on either side. We performed endoscopic lithotripsy to remove the encrusted ureteral stents. The bilaterally encrusted metallic ureteral stents were successfully removed using Ho:YAG laser lithotripsy after inserting another ureteral stent placement besides the encrusted metallic ureteral stents.

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Routine Short-Term Ureteral Stent in Living Donor Renal Transplantation: Introduction of a Simple Stent Removal Technique Without Using Anesthesia and Cystoscope

Transplantation Proceedings ◽

10.1016/j.transproceed.2011.09.062 ◽

2011 ◽

Vol 43 (10) ◽

pp. 3747-3750 ◽

Cited By ~ 6

Author(s):

J. Dong ◽

J. Lu ◽

Q. Zu ◽

S. Yang ◽

S. Sun ◽

...

Keyword(s):

Renal Transplantation ◽

Living Donor ◽

Ureteral Stent ◽

Short Term ◽

Stent Removal ◽

Removal Technique

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Silicone or polyurethane ureteral stent: assessment of the intensity of stent-related symptoms

Aspirantskiy Vestnik Povolzhiya ◽

10.17816/2072-2354.2020.20.3.125-131 ◽

2020 ◽

Vol 20 (5-6) ◽

pp. 125-131

Author(s):

Nariman K. Gadzhiev ◽

Sergey B. Petrov ◽

Andrey O. Ivanov ◽

Vladimir M. Obidnyak ◽

Vladislav E. Grigoriev ◽

...

Keyword(s):

Ureteral Stent ◽

Control Group ◽

Ureteral Stents ◽

Stent Removal ◽

Pain Visual Analog Scale ◽

Group A ◽

Bladder Symptoms ◽

Cook Medical ◽

Group B ◽

Experimental Group

Introduction. About 80% of patients with ureteral stents experience symptoms associated with them. We believe that the intensity of stent-assosiated symptoms (SAS) can be reduced by the replacement of the stent material with a less solid one. The aim of our research was to compare the intensity of the symptoms and signs as well as the safety of silicone and poly urethane ureteral stent. Materials and methods. The study included 70 patients who were divided into two groups. Group A included patients who were placed with polyurethane stents (Rsch, Teleflex). The experimental group B included patients who were placed with silicone stents (Cook Medical). Specialized questionnaires like pain Visual Analog Scale (VAS) and Overactive Bladder Symptoms (OAB) questionnaires were used to study the patients for SAS severity 1 hour after the stent was placed, in the middle of the observation period and before the stent was removed or ureteroscopy was performed. In addition, each group was assessed for the effectiveness of the stent placement, the presence of hematuria, the number of unscheduled visits to the doctor and the degree of stent incrustation. Results. A total of 70 patients participated in the study, while the control group A included of 30 patients and experimental group B included 40 patients. Group B participants having silicone ureteral stents showed significantly lower average VAS values 2 weeks before stent removal and shortly before stent removal (p = 0.023 and p = 0.014 respectively). No other comparisons between the two groups were statistically significant. Conclusions. The obtained findings demonstrate that silicone ureter stents, unlike polyurethane ureter stents, cause less pain according to VAS two weeks before and during the stent removal procedure.

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