What is the function of the filter in mammography?

What is the function of the filter in mammography?

• A. Calibrate the detector response
• B. Increase patient dose
• C. Remove photon energies above and below the range needed for mammo
• D. Focus the beam

Answer: (C)

Filtration shapes the x-ray spectrum to keep only photons in the energies that are most useful for breast imaging. By absorbing the low-energy portion of the beam, the filter reduces dose to the patient and prevents those photons from contributing little to image formation. This beam hardening moves the remaining photons into a more optimal energy range for differentiating tissue types, improving image quality while keeping dose down. The filter does not calibrate the detector, it does not increase patient dose, and beam focusing is achieved by geometry and collimation, not filtration.

Filtration shapes the x-ray spectrum to keep only photons in the energies that are most useful for breast imaging. By absorbing the low-energy portion of the beam, the filter reduces dose to the patient and prevents those photons from contributing little to image formation. This beam hardening moves the remaining photons into a more optimal energy range for differentiating tissue types, improving image quality while keeping dose down. The filter does not calibrate the detector, it does not increase patient dose, and beam focusing is achieved by geometry and collimation, not filtration.