What does attenuation refer to in computed tomography?

Attenuation specifically refers to the reduction in intensity of the x-ray beam as it passes through an object. This phenomenon occurs because different materials have varying densities and atomic compositions, which means that they can absorb or scatter x-rays to differing extents. For instance, dense materials like bone will attenuate x-rays more than soft tissues, leading to a contrast on the image that helps differentiate between various structures within the body. Understanding attenuation is crucial for interpreting CT images, as it influences both image quality and diagnostic accuracy.