What occurs when an imaging process does not sample all relevant frequencies of a signal?

When an imaging process does not sample all relevant frequencies of a signal, it leads to aliasing. Aliasing is a phenomenon that occurs when the sampling frequency is insufficient to accurately capture the range of frequencies present in the signal. In the context of imaging, this means that high-frequency details can become misrepresented or inaccurately reproduced, resulting in visual distortions.

In CT imaging, proper sampling ensures that the resultant images accurately reflect the anatomy being scanned. If the frequencies are not adequately sampled, the image can show unexpected patterns or artifacts that do not correspond to true anatomical features, leading to difficulties in interpretation.

This concept is critical in understanding how image quality can be affected by the technological and procedural parameters used in CT scanning, emphasizing the importance of appropriate sampling rates to prevent aliasing and ensure diagnostic accuracy.