Computed Tomography Technologist Practice Exam 2025 – All-in-One Guide for Exam Success!

Aliasing in computed tomography refers to an artifact that occurs when a limited sampling frequency leads to misinterpretation of imaging data. The appearance of fine stripes or patterns radiating from a dense structure is a classic example of aliasing. This phenomenon typically arises when the resolution of the scanner is not adequate to capture the intricate features of the anatomy being imaged, resulting in misleading visual artifacts. These artifacts can detract from the diagnostic value of the images, making it essential for technologists to recognize and manage them effectively.

The other choices describe different but related imaging phenomena. For instance, loss of signal strength refers to a decrease in the quality or intensity of the scan, which is not specifically linked to aliasing. Beam hardening affects the image quality by causing distortions due to variation in attenuation, but it does not relate to the aliasing artifacts seen in CT imaging. Lastly, the need for re-calibration of the machine typically addresses issues of overall performance and accuracy rather than specifically relating to the visual artifacts caused by aliasing. Understanding aliasing and its implications helps radiologic technologists improve image acquisition techniques and minimize artifacts in CT scans.