Comparison of Ureteral Stent Designs in Children With Kidney Stones

NCT07742358 | Recruiting

• 1 other identifier: 4103
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

This study will compare two commonly used ureteral stents in children and adolescents undergoing staged treatment for kidney stones. Ureteral stents are small tubes placed between the kidney and bladder to help urine drain after a procedure. Although stents are effective, they can cause bladder spasms, pain, urinary urgency, and other uncomfortable symptoms. Participants aged 8 to 18 years will receive both a standard Cook double-J ureteral stent and a Polaris Ultra ureteral stent during two planned procedures. The order in which the stents are used will be assigned at random, and participants and caregivers will not be told which stent is in place during each treatment period. Participants will report bladder spasms, pain, urinary symptoms, and quality of life through questionnaires and symptom assessments. The study will determine whether differences in stent design affect comfort, bladder spasms, urinary tract infections, or other stent-related complications. Both stents are approved by Health Canada and are used as part of routine clinical care.

Conditions

Pediatric Urolithiasis; Ureteral Stent-Related Symptoms

Outcome Measures

Primary Outcomes (1)

• Frequency of Bladder Spasm Episodes

  Postoperative Days 1, 3, and 7 during each of two stent treatment periods

Secondary Outcomes (3)

• Canadian Endourology Group Stent Symptom Score

  Postoperative Days 1, 3, and 7 after each stent placement, over approximately 8-12 weeks

• Stent-Related Pain Intensity Measured Using a Visual Analog Scale

  Postoperative Days 1, 3, and 7 after each stent placement, over approximately 8-12 weeks

• Incidence of Symptomatic Urinary Tract Infection

  During each 4- to 6-week ureteral stent indwelling period

Other Outcomes (1)

• Validity and Responsiveness of the Canadian Endourology Group Stent Symptom Score

  From baseline through completion of both treatment periods, approximately 8-12 weeks

Study Arms (2)

Polaris Ultra Followed by Cook Double-J

EXPERIMENTAL

Participants assigned to this sequence will receive the Polaris Ultra ureteral stent during the first clinically indicated ureteroscopic procedure. At the subsequent staged procedure, the Polaris Ultra stent will be removed and participants will receive the Cook double-J ureteral stent for the second treatment period. Each stent will remain in place for approximately 4 to 6 weeks. Participants will complete symptom, pain, and quality-of-life assessments during both treatment periods.

Device: Polaris Ultra Ureteral Stent; Device: Cook Double-J Ureteral Stent

Cook Double-J Followed by Polaris Ultra

EXPERIMENTAL

Participants assigned to this sequence will receive the Cook double-J ureteral stent during the first clinically indicated ureteroscopic procedure. At the subsequent staged procedure, the Cook stent will be removed and participants will receive the Polaris Ultra ureteral stent for the second treatment period. Each stent will remain in place for approximately 4 to 6 weeks. Participants will complete symptom, pain, and quality-of-life assessments during both treatment periods.

Device: Polaris Ultra Ureteral Stent; Device: Cook Double-J Ureteral Stent

Interventions

Polaris Ultra Ureteral Stent DEVICE

The Polaris Ultra ureteral stent is a commercially available, Health Canada-approved double-J ureteral stent used for temporary ureteral drainage after ureteroscopic stone treatment. The stent has a dual-durometer polymer design with a firmer proximal segment and a softer distal bladder segment, as well as a hydrophilic coating. In this study, a 6 French stent of a length appropriate for the participant's anatomy will be placed cystoscopically and will remain in place for approximately 4 to 6 weeks during one treatment period.

Cook Double-J Followed by Polaris Ultra; Polaris Ultra Followed by Cook Double-J

Cook Double-J Ureteral Stent DEVICE

The Cook double-J ureteral stent is a commercially available, Health Canada-approved ureteral stent used as the standard-of-care comparator for temporary ureteral drainage after ureteroscopic stone treatment. It is a conventional polyurethane double-J stent with pigtail coils at the renal and bladder ends. In this study, a 6 French stent of a length appropriate for the participant's anatomy will be placed cystoscopically and will remain in place for approximately 4 to 6 weeks during one treatment period.

Cook Double-J Followed by Polaris Ultra; Polaris Ultra Followed by Cook Double-J

Eligibility Criteria

• Age: 8 Years - 18 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Ability of the participant and/or legally authorized representative to provide written informed consent, with assent obtained from the participant when appropriate, in accordance with institutional policy.
• Age 8 to 18 years at the time of enrollment.
• Undergoing staged ureteroscopic stone management requiring two sequential ureteral stent placements as part of standard clinical care.
• Planned placement of unilateral ureteral stents with an anticipated indwelling duration of approximately 4 to 6 weeks per stent.
• American Society of Anesthesiologists Physical Status Classification I or II at the time of surgery.
• Ability and willingness of the participant and/or caregiver to comply with study procedures, including completion of symptom assessments and questionnaires at specified time points.
• Ability to complete study questionnaires in English, either independently or with caregiver assistance.

You may not qualify if:

• American Society of Anesthesiologists Physical Status Classification III or higher at the time of surgery.
• Active urinary tract infection, defined as clinical symptoms consistent with infection and a positive urine culture, at the time of screening or before stent placement.
• Significant baseline bladder dysfunction, including neurogenic bladder, overactive bladder requiring chronic anticholinergic therapy, or prior bladder augmentation, that could confound assessment of stent-related symptoms.
• Requirement for bilateral ureteral stent placement or planned bilateral ureteroscopic procedures.
• Known hypersensitivity or allergy to materials used in either ureteral stent included in the study.
• Pregnancy or lactation, as determined by clinical assessment and/or institutional testing requirements, where applicable.
• Use of chronic opioid therapy, chronic anticholinergic medications, or other medications that, in the investigator's opinion, would substantially interfere with assessment of stent-related pain or urinary symptoms.
• Participation in another interventional clinical trial that could interfere with the objectives or outcome assessments of this study.

Sponsors & Collaborators

• The Hospital for Sick Children: lead

Study Sites (1)

SickKids

Toronto, Ontario, M5G 1E8, Canada

RECRUITING

Central Study Contacts

Michael Chua, MD

CONTACT

416-813-7654; michael.chua@sickkids.ca

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Masking Details: Participants and their caregivers will be blinded to the ureteral stent type used during each treatment period. The operating surgeon and clinical study team involved in device placement will not be blinded because of visible and technical differences between the stents. Surgeons will not collect the patient-reported outcome measures. Unblinding may occur when knowledge of the stent type is medically necessary for participant management.
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Staff Urologist

Model Details: Participants will be randomized in a 1:1 ratio to one of two treatment sequences. One sequence will receive the Polaris Ultra ureteral stent during the first treatment period followed by the Cook double-J ureteral stent during the second period. The other sequence will receive the stents in the reverse order. Each participant will therefore receive both interventions and serve as their own control.

Study Record Dates

• First Submitted: July 27, 2026
• First Posted: August 3, 2026
• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): September 1, 2027
• Study Completion (Estimated): September 1, 2027
• Last Updated: August 3, 2026

Record last verified: 2026-07

Locations

CA (1)