A novel, ring-connected stent versus conventional GI stents: comparative study of physical properties and migration rates in a canine colon obstruction model.

Background: Migration of stents is one of the most common adverse events in covered stent placement in GI tract obstruction.

Objective: To compare physical property and migration rates in a canine colon obstruction model among a novel stent and conventional stents.

Design: Comparative physical test and animal study.

Setting: Medical device testing laboratory and animal laboratory.

Subjects: Mongrel dogs (N=26).

Interventions: Surgical colon obstruction followed by placement of a novel (n=13) or conventional (n=13) stent.

Main Outcome Measurements: Physical properties, migration, and adverse events.

Results: The novel stent showed better flexibility, as in a physical test of longitudinal compressibility and axial force, than did conventional stents, and it withstood the fatigue test for 10 days. In terms of radial force and tensile strength, the novel stent showed the same or better results than conventional stents. In a canine colon obstruction model, the migration rate of a novel stent was significantly lower than that of a conventional stent (2/13, 15.4% vs 8/13, 61.5%; P=.008).

Limitations: Animal study of limited size.

Conclusion: The novel, ring-connected stent is more flexible and more resistant to migration than the conventional stents.