What is the greatest factor contributing to scatter radiation?

The greatest factor contributing to scatter radiation is patient thickness. When X-rays pass through the body, thicker anatomical structures absorb and deflect more photons than thinner structures. As the thickness of the patient increases, the likelihood of photons interacting with tissues in a way that generates scatter radiation also increases. This scatter can contribute to the overall radiation exposure that reaches the image receptor and can degrade image quality.

In contrast, tube voltage, beam filtration, and exposure time do have roles in the production of scatter radiation, but they are not as directly impactful as patient thickness. While higher tube voltage can increase the energy of the X-rays and potentially result in different interactions, and beam filtration can reduce the number of lower-energy photons that contribute to scatter, the primary source of scatter is indeed related to the amount of tissue the radiation must penetrate. Exposure time is more about the duration of radiation exposure rather than the amount of scatter produced. Therefore, patient thickness stands out as the key factor in the generation of scatter radiation.