Patel and colleagues used a previously described batch-flow artificial urine model with a static mixer (pictured below), and measured the encrustation that occurred on Pellethane, 2-hydroxyethyl methacrylate (HEMA)-coated Pellethane, and tetraethylene glycol dimethyl ether (tetraglyme)-coated Pellethane stents and catheters versus that that occurs on commercially available stents and catheters (a hydrogel-coated latex urinary catheter by Bard® and a hydrophilic polymer-coated polyurethane ureteral stent Cook Medical®. The surface treatments, HEMA and tetraglyme, serve to resist protein absorption. Encrustation was quantified by weight gain of the stents.
After a 30-day trial, all 3 of the Pellethane models exhibited less weight gain compared to the commercial stents. These results are shown in the table below. Additionally, electron microscopy showed less encrustation on the Pellethane models, though all models had at least a small amount of encrustation.
An audience member noticed that there were, in one case, a negative weight gain of the Pellethane model, which Dr. Patel hypothesizes was due to the surface coating’s leaching into the solution. Dr. Patel also stated that 3, 6, and 9-month clinical trials are planned to study the use of Pellethane-based stents and catheters. Additionally, he indicated that future studies will examine stone types other than struvite stones, which were the sole focus of the current study.
Presented by: Roshan M. Patel, MD, Assistant Clinical Professor, University of California, Irvine, Department of Urology, Orange, California
Co-Authors: Kevin Guan, Taylor Capretz, Krista Larson, University of California, Irvine, USA, Jaime Landman, Professor and Chair, Department of Urology, University of California, Irvine, Orange, CA, Orange, California, Buddy Ratner, Seattle, Washington, Ralph Clayman, Professor, University of California, Irvine, Department of Urology, Orange, California