Sometimes radiopacity is required to visualize the location of your device during a procedure, or perhaps to make sure it’s where you left it. When x-rays are utilized with metallic objects, the image can suffer from shadowing effects due to the strong contrast with the surrounding tissue or bone.
An ideal radiopaque solution is a combination of plastic additives that can include Barium Sulfate and a host of other particles. Depending on the spectrum of the source, the desired amount of attenuation at specific energies, and final part geometries; the specified powder and concentration is added to a wide variety of plastics by custom blending houses. If you’re not 100% sure of how radiopaque the device needs to be, conducting trials with multiple concentrations is done by providing virgin pellets along with radiopaque doped plastics. This allows the injection molding house to shoot a variety of concentrations for subsequent evaluation. Barium Sulfate is suggested in medical device design due to its low cost (often less expensive than the native plastic it is displacing), and availability in certified biocompatible forms. In fact, it is often used in children’s toys to provide radiopacity in the somewhat likely event it is swallowed.