Comparison of the effects of extrinsic compression on the drainage performance of three ureteric stents.

OBJECTIVES: To share our centre's experience dealing with ureteric obstruction, in particular malignant obstructions, by investigating the deformation and flow velocity of three commonly used, readily accessible ureteric stents under at different compression levels and surface change at three time points (new, 1 month and 3 months after implantation). SUBJECTS AND METHODS: Scanning electron microscope (SEM) analysis was conducted on ureteric JJ stents, including the Cook Universa Soft, the Kang Yi Bo (KYB) antireflux and the Urovision Visiostar ESWL JJ stents. Deformation caused by compression was measured using a digital force gauge. Intraluminal flow velocity was tested with the stents subject to different compression levels. RESULTS: The Urovision Visiostar JJ stent demonstrated significantly better anti-compression capability. The Cook Universa Soft and KYB antireflux JJ stents showed favourable draining velocity without compression, but the velocity dropped substantially on compression. The velocity of the KYB antireflux JJ stent reduced substantially after 3 months of implantation, while the Urovision Visiostar achieved the best draining effect when under compression at all three time points. CONCLUSION: The Urovision Visiostar JJ stent demonstrated significantly greater resistance to compression than the other two JJ stents, as well as better drainage under compression. Patients with benign or malignant ureteric compression might benefit from use of the Urovision Visiostar stent. Large prospective clinical trials are needed to confirm these findings.