Investigation of a novel gradient degradable ureteral stent in a beagle dog model

Ureteral stents are widely used in the department of urology, while the stent could result in many stent-associated complications, such as encrustation, a forgotten stent and patient discomfort. Thus, we developed a novel gradient degradable ureteral stent, which could degrade gradient in vivo, and assessed its effectiveness of the drainage, degradation and biocompatibility in a beagle dog model. In the present study, the degradation time and cytotoxicity were investigated in vitro. And the beagle dogs were inserted with a degradable stent or a biostable stent, and blood studies, liver function tests, renal function tests, urine studies, X-ray, excretory urograms and computerized tomography were performed at immediately, two weeks, four weeks and six weeks postoperative. The results showed that the drainage of the novel stent is similar to the conventional stent, while the biocompatibility and antibacterial ability of the novel stents are better than the conventional stents. The stents we developed provide an alternative for urologists and more assays would be performed in detail to assess the property of the stents.