When can beam hardening artifacts occur in CT imaging?

Beam hardening artifacts in CT imaging primarily occur when high kilovolt peak (kVp) settings are used. This phenomenon is related to how different tissues absorb X-rays at varying rates. In CT, higher kVp settings increase the energy of the X-ray beam, which enhances the penetration power of the radiation but also leads to a situation where lower-energy X-rays are preferentially absorbed by dense structures within the body, such as bone. This differential absorption results in a beam of higher average energy—hence the term "beam hardening."

As a result, when the X-ray beam passes through denser tissues, such as bone, it becomes "hardened," leading to artifacts on the resulting images, such as dark bands or streaks that can obscure or mimic pathology. This effect can be particularly pronounced in regions where there are significant variations in tissue density.

Other options, while they may cause image quality issues, do not specifically relate to beam hardening. For instance, patient motion can introduce blurring, and slow rotation speeds can impact image clarity but do not cause beam hardening. Mispositioned patients may result in poor image acquisition, but again, this does not directly lead to beam hardening artifacts. Thus, the occurrence