What happens to the quantity of scattered radiation when the size of the radiographic field is limited?

When the size of the radiographic field is limited, the quantity of scattered radiation decreases. This is due to the fact that limiting the field size reduces the volume of irradiated tissue, which in turn decreases the amount of scattered radiation produced.

Scattering occurs when x-ray photons interact with matter, and larger fields encompass more tissue, leading to more opportunities for these interactions and consequently more scatter. By confining the radiographic field, the exposure to surrounding tissues is minimized, resulting in lesser scatter. Therefore, it is essential in radiographic practice to use collimation to optimize image quality and reduce radiation dose. This principle is used not only to improve diagnostic quality but also to enhance patient safety by minimizing unnecessary exposure.