Filtration's effect on the beam spectrum is best described by which statement?

Filtration's effect on the beam spectrum is best described by which statement?

• A. It Reduces Low-Energy Photons
• B. It Reduces Low-Energy Photons And Increases Average Energy
• C. It Has No Effect On Spectrum
• D. It Changes The Direction Of Photons

Answer: (A)

Filtration hardens the beam by removing the low-energy photons produced at the anode. Those soft photons contribute more to patient dose than to image formation, so eliminating them reduces dose while also shifting the remaining photons to higher energies. As a result, the spectrum becomes harder and the average energy increases. Filtration does not change the photons’ direction, and it does affect the spectrum, so the description that includes both removing low-energy photons and increasing the average energy is the most accurate.

Filtration hardens the beam by removing the low-energy photons produced at the anode. Those soft photons contribute more to patient dose than to image formation, so eliminating them reduces dose while also shifting the remaining photons to higher energies. As a result, the spectrum becomes harder and the average energy increases. Filtration does not change the photons’ direction, and it does affect the spectrum, so the description that includes both removing low-energy photons and increasing the average energy is the most accurate.