What type of artifacts are primarily caused by metal objects?

Streak artifacts are primarily caused by metal objects, resulting from the interaction between the metal and the imaging system. When x-rays pass through a metal object, there are significant differences in the attenuation of the x-ray beam due to the dense nature of the metal. This can lead to a phenomenon where the surrounding areas on the image receive incorrect signal information, resulting in dark streaks or lines radiating from the metal.

While the other types of artifacts may occur in CT imaging due to different reasons—such as motion artifacts primarily stemming from patient movement during scanning, aliasing arising from insufficient temporal resolution, and edge gradient effects related to the sharp transition in tissue density—streak artifacts specifically highlight the influence of metallic materials in the imaging process. Understanding this relationship helps in clinical settings to recognize and mitigate the effects of metal on image quality, thereby improving diagnostic accuracy.