Compton scattering adds to patient dose through an event called:

Compton scattering adds to patient dose through an event called:

• A. Excitation
• B. Divergence
• C. Scattering
• D. Ionization

Answer: (D)

When Compton scattering happens in tissue, part of the photon’s energy is transferred to an outer electron, ejecting it from its atom. That ejected electron travels through the tissue, creating many ion pairs as it loses energy. The energy deposited in tissue—and thus the patient’s dose—comes from these ionization events. So, the event that adds to patient dose is ionization. Excitation would only raise an electron to a higher bound state without removing it, which doesn’t contribute as the main dose mechanism at diagnostic energies. Divergence describes beam spread, not energy deposition. Scattering describes the process itself but the dose comes from the ionization caused by the ejected electron.

When Compton scattering happens in tissue, part of the photon’s energy is transferred to an outer electron, ejecting it from its atom. That ejected electron travels through the tissue, creating many ion pairs as it loses energy. The energy deposited in tissue—and thus the patient’s dose—comes from these ionization events. So, the event that adds to patient dose is ionization.

Excitation would only raise an electron to a higher bound state without removing it, which doesn’t contribute as the main dose mechanism at diagnostic energies. Divergence describes beam spread, not energy deposition. Scattering describes the process itself but the dose comes from the ionization caused by the ejected electron.