Which two events result in radiation energy being absorbed in the body during a radiographic procedure?

Which two events result in radiation energy being absorbed in the body during a radiographic procedure?

• A. Compton scattering and photoelectric effect
• B. Transmission
• C. Compton scattering
• D. Classical scattering

Answer: (A)

The energy deposited in body tissues during radiography comes from interactions that transfer energy to matter. The two events that do this most directly are the photoelectric effect and Compton scattering. In the photoelectric effect, the incoming photon is completely absorbed by an electron that is bound in an atom, and that energy goes into ejecting the electron. The ejected electron then deposits its energy in the surrounding tissue, contributing to dose. In Compton scattering, the photon transfers part of its energy to a recoil electron as it scatters off an outer electron. That energy transfer is absorbed by the tissue when the electron ionizes and loses energy. The photon that remains is scattered with lower energy and may go on, but the interaction itself deposits energy in the body. Transmission and classical (Rayleigh) scattering do not deposit energy in the tissue: transmission implies no interaction, and classical scattering is largely elastic with negligible energy transfer to electrons. So the two events that result in radiation energy being absorbed in the body are the photoelectric effect and Compton scattering.

The energy deposited in body tissues during radiography comes from interactions that transfer energy to matter. The two events that do this most directly are the photoelectric effect and Compton scattering.

In the photoelectric effect, the incoming photon is completely absorbed by an electron that is bound in an atom, and that energy goes into ejecting the electron. The ejected electron then deposits its energy in the surrounding tissue, contributing to dose.

In Compton scattering, the photon transfers part of its energy to a recoil electron as it scatters off an outer electron. That energy transfer is absorbed by the tissue when the electron ionizes and loses energy. The photon that remains is scattered with lower energy and may go on, but the interaction itself deposits energy in the body.

Transmission and classical (Rayleigh) scattering do not deposit energy in the tissue: transmission implies no interaction, and classical scattering is largely elastic with negligible energy transfer to electrons.

So the two events that result in radiation energy being absorbed in the body are the photoelectric effect and Compton scattering.