Computed Tomography Technologist Practice Exam

Beam-hardening artifacts refer to the phenomenon that occurs when lower energy photons in an X-ray beam are absorbed more than higher energy photons as the beam passes through dense materials, such as bone or metal. This leads to an increase in the average energy of the transmitted beam, which can cause darker areas to appear on the image, commonly referred to as "cupping" artifacts.

Cupping artifacts manifest as a reduction in image density at the periphery of the scanned area and are typically seen in images involving thick structures. This name reflects the concave shape that often appears due to this effect. These artifacts can mislead the interpretation of scans, especially in regions with high-density materials, by distorting the true appearance of the tissue or structures being imaged. By recognizing this terminology, radiologists and technicians can better understand and mitigate these artifacts during image acquisition and interpretation.

The other terms do refer to different types of artifacts encountered in imaging but do not specifically describe the beam-hardening phenomenon in the same way. For example, scatter artifacts relate to the scattering of X-ray photons and their impact on the quality of the image, while ring artifacts involve circular patterns due to inconsistencies in the detector, and edge artifacts result from abrupt changes in tissue