Radiologic evaluation of intravesical/subureteric injection of polytef

In order to study the transurethral intravesical/suburetric injection of polytef paste (polytetrafluoroethylene), eight monkeys were injected with 0.4 mL of polytef. After 1 year, five monkeys were killed. Migration of polytef particles was shown on pathologic study. The authors have continued to follow three monkeys with radiography. Two additional monkeys have been imaged, received injections, and have also been followed. MR imaging and CT were initially used to evaluate the site of injection at 12 and 18 months. Surprisingly, large granuloma-like masses had developed at the site. These monkeys were again imaged with the addition of US at 24 months after surgery. US showed only an area of intense echogenicity without defining the exact size of the mass. MR imaging best defined the lesion and showed growth of the granulomas over time