The effects of various indwelling ureteral catheter materials on the normal canine ureter

In an attempt to objectively evaluate the biocompatibility of materials commonly used for ureteral stenting, stent-catheters made of four different materials were placed randomly in 31 ureters of 19 mongrel dogs. Animals underwent urography at four weeks and were sacrificed at six weeks. Mild hydronephrosis was noted in eight instances, essentially unrelated to specific material. Silicone, C-flex and polyurethane stents caused a similar, mild degree of ureteral edema, but ureters stented with Silitek demonstrated fairly marked edema. Epithelial ulceration and erosion, often severe, occurred with all polyurethane stents, and rarely with the three other materials. All materials differed statistically from controls, and C-flex caused less reaction overall than polyurethane, indicating differences in biocompatibility of the various materials which may be relevant to their use in patients undergoing long-term ureteral stenting. In practical terms, these suggest that certain materials, notably silicone and C-flex, are more suitable for ureteral stenting than others.