What is the factor that radiation dose is directly proportional to in CT?

In computed tomography (CT), radiation dose is directly proportional to scan volume. This reflects the amount of tissue being irradiated during the scanning process. When the scan volume increases, more body parts are included in the imaging area, resulting in a higher radiation dose.

For instance, if a CT scan includes a larger area of the body or multiple contiguous slices, the cumulative radiation exposure will also increase. This relationship is crucial for optimizing scans to ensure that they provide necessary diagnostic information while minimizing exposure to radiation.

While patient age, scan length, and body mass index may have some influence on the overall management and assessment of CT imaging, they do not directly dictate the amount of radiation exposure in the same clear and quantifiable manner as scan volume does. Understanding the impact of scan volume helps technologists and healthcare providers effectively balance diagnostic needs with patient safety.