Indwelling ureteral
stents represent a very frequently used procedure in urological clinical practice that ensures the drainage of urine from the upper urinary tract. However, the
stents could result in many
stent-associated complications, such as encrustation and patient discomfort. We developed a new type of biodegradable ureteral
stents produced from degradable
polyurethane and
magnesium alloys. In the present study, we investigated the biocompatibility and the property of degradation of the biodegradable ureteral
stents. We evaluated the cytotoxicity of biodegradable ureteral
stent by the MTT assay in vitro. The rabbit dorsal muscle embedding test was used to assess the biocompatibility of the degradable
stents.
Inflammation and
fibrosis of muscle tissue were noted to evaluate compatibility at 1, 2, 4, 6 weeks after
stents implanted in muscle. The degradation of the biodegradable ureteral
stents was assessed by measuring the
weight loss of the samples in AUS (artificial urine
solution). For validating the degradation property of degradable
stents in vivo, we inserted a degradable
stent or a conventional biostable
stent into Bama pigs. Furthermore, blood studies, liver function tests, renal function tests, urine studies, and computerized tomography (CT) were performed postoperatively. Our study confirms that the degradable
polyurethane-based biodegradable ureteral
stent has good biocompatibility. Our biodegradable ureteral
stents were completely degraded within 4 weeks and provided a better ability of drainage than conventional
stents. They hold promise for decreasing the need for a secondary procedure and
stent related morbidity, such as
infections.