Which imaging modality is known to utilize ionizing radiation?

The imaging modality that utilizes ionizing radiation is X-ray. This type of imaging works by passing a controlled amount of radiation through the body, which then captures images based on the varying absorption of radiation by different tissues. Dense structures, such as bones, absorb more radiation and appear lighter on the X-ray image, while softer tissues absorb less and appear darker.

X-rays are commonly used for a variety of diagnostic purposes, including identifying fractures, infections, and abnormalities in various body parts. The use of ionizing radiation in X-ray imaging is an essential characteristic that distinguishes it from other modalities.

In contrast, ultrasound uses sound waves, MRI employs strong magnetic fields and radiofrequency waves, and CT scans, although they do involve ionizing radiation, specifically utilize a combination of X-ray technology to create detailed cross-sectional images. Thus, X-ray is the most straightforward example of an imaging modality that applies ionizing radiation.