Related Experiment Video
Updated: Feb 8, 2026

A Murine Model of Irreversible and Reversible Unilateral Ureteric Obstruction
Published on: December 20, 2014
A Prospective Randomized Comparison of a Covered Metallic Ureteral Stent and a Double-J Stent for Malignant Ureteral
Jong Woo Kim1, Bumsik Hong2, Ji Hoon Shin1
1Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505, Korea.
Objective:
To compare the safety and efficacy between a covered metallic ureteral stent (CMS) and a double-J ureteral stent (DJS) for the treatment of a malignant ureteral obstruction (MUO).
Materials And Methods:
Nineteen patients (seven men and 12 women; mean age, 53.4 years) were randomly assigned to the CMS (n = 10) or DJS (n = 9) group. The following were compared between the two groups: technical success, i.e., successful stent placement into desired locations; stent malfunction; stent patency, i.e., no obstruction and no additional intervention; complications; and patient survival.
Results:
The technical success rate was 100% in all 10 and 12 ureteral units in the CMS and DJS groups, respectively. During the mean follow-up period of 253.9 days (range, 63-655 days), stent malfunction was observed in 40.0% (4/10) and 66.7% (8/12) in the CMS and DJS groups, respectively. In the per-ureteral analysis, the median patency time was 239.0 days and 80.0 days in the CMS and DJS groups, respectively. The CMS group yielded higher patency rates compared with the DJS group at three months (90% vs. 35%) and at six months (57% vs. 21%). The overall patency rates were significantly higher in the CMS group (p = 0.041). Complications included the migration of two metallic stents in one patient in the CMS group, which were removed in a retrograde manner. The two patient groups did not differ significantly regarding their overall survival rates (p = 0.286).
Conclusion:
Covered metallic ureteral stent may be effective for MUO.
Related Concept Videos
Molecular Comparison of Gases, Liquids, and Solids
Bonding in Metals
Metallic Solids
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
Alkali Metals
Table 1: Properties of the alkali metals
The Sense of Self: Reflected Self-Appraisal and Social Comparison
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...

