Photon starvation is one source of streak artifact which may occurs in CT. It is seen in high attenuation areas, particularly behind metal implants. Because of high attenuation insufficient photons reach the detector surface resulting in characteristic artifact. During reconstruction process, the noise is greatly magnified leading to streaks in the image. The artifact can be reduced by automatic tube current modulation and adaptive filtration.
- Artifacts in CT: Recognition and avoidance , Radiographics 2004;24:1679-1691