Which image quality factor is defined as the structural sharpness recorded in the radiographic image?

• A. Spatial resolution
• B. Contrast
• C. Brightness
• D. Distortion

Answer: (A)

Spatial resolution corresponds to the structural sharpness recorded in the radiographic image. It describes how well the system renders fine details and edges as distinct rather than blurred together. The other terms don’t capture edge clarity: contrast is the difference in gray levels between adjacent structures, brightness is the overall lightness of the image, and distortion is a geometric misrepresentation of size or shape. Factors that affect spatial resolution include the focal spot size, the distance from the source to the image receptor, the distance from the object to the receptor, motion, and detector pixel size or sampling. In short, this term directly measures how sharply fine details are depicted on the image.