Comparison of Polaris Ultra Ureteral Stent and Tria Firm Ureteral Stent on Deposition of Encrustation Following Short-Term Placement: A Prospective, Single-blind, Randomized Controlled Trial.

Comparison of Polaris Ultra Ureteral Stent and Tria Firm Ureteral Stent on Deposition of Encrustation Following Short-Term Placement: A Prospective, Single-blind, Randomized Controlled Trial. - Comparison of Polaris Ultra Ureteral Stent and Tria Firm Ureteral Stent on Deposition of Encrustation Following Short-Term Placement

Status

Active, not recruiting

Phases

Phase 4

Study type

Interventional

Source

JPRN

Registry ID

JPRN-UMIN000037006

Enrollment

Registered

2019-06-20

Start date

2019-07-01

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Patients with urolithiasis

Interventions

Placement of Tria Firm Ureteral Stent during 14 days postoperatively Placement of Polaris Ultra Ureteral Stent during 14 days postoperatively

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: 1.>20 year-old adults 2.Patients undergoing ureteroscopy (URS) for renal and/or ureteral stones 3.Patients with informed consent

Exclusion criteria

Exclusion criteria: 1. Patients potentially requiring ureteric stent placement for >14 days postoperatively 2. Patients requiring antibiotics use prior to URS due to the presence of urinary tract infection 3. Pregnant 4. Patients with difficulty of communication 5. patients who have been determined to be unsuitable as a subject by a physician

Design outcomes

Primary

Measure	Time frame
Encrustation volume in inner wall of the ureteral stent (mm3)	—

Secondary

Measure	Time frame
1. Intraluminal obstruction rate (%) (at the narrowest point of the stent) 2. Outerwall stent encrustation volume (mm3) 3. Outerwall stent encrustation-sectional volume: proximal/body/distal (mm3) 4. Hydronephrosis grade before removal of stents 5. Stent-related complications (Dislodgment, migration, UTI, readmission etc.) 6. Stone composition (stone fragments, encrustation stone)	—

Countries

Japan

Contacts

Public ContactTakashi Yoshida

Kansai medical university hospital Department of Urology and Andrology

yoshidtk@takii.kmu.ac.jp072-804-0101

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026