Tungsten polymers are used to produce
catheters and other devices that are inserted into the body for diagnostic or
interventional procedures are commonly filled with substances opaque to x-rays,
thereby rendering the devices visible under fluoroscopy or x-ray imaging.
These fillers, or
radiopacifiers—tungsten(typically dense metal powders)—affect the energy
attenuation of photons in an x-ray beam as it passes through matter, reducing
the intensity of the photons by absorbing or deflecting them, could be a
suitable material for X-ray absorption for many radioan facilities especially
medical devices. Because these materials exhibit a higher attenuation
coefficient than soft tissue or bone, they appear lighter on a fluoroscope or
x-ray film. This visibility provides the contrast needed to accurately position
the device in the affected area. Image contrast and sharpness can be varied by
the type and amount of radiopacifier used, and can be tailored to the specific
application of the device.
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