In digital radiography, what does EI stand for?

• A. Exposure Index
• B. Exposure Intensity
• C. Electronic Index
• D. Exposure Indicator

Answer: (A)

In digital radiography, EI represents a numeric gauge of how much X-ray exposure the detector has recorded, which helps you judge image brightness and keep image quality consistent while managing patient dose. The term stands for Exposure Index, the standard label used to describe this exposure metric. Some systems use different scales or terminology, but the concept is the same: the index quantifies detector exposure so you can adjust technique to avoid underexposure (noisy, grainy image) or overexposure (unnecessary dose). The other options aren’t the established term for this metric—Exposure Intensity and Electronic Index aren’t the standard name, and Exposure Indicator is close but the widely accepted expansion is Exposure Index.