What is the primary purpose of a grid in radiology?

The primary purpose of a grid in radiology is to reduce scatter radiation. Grids are designed to absorb scattered photons that arise from interactions of the primary beam with the patient and other materials within the radiographic field. When the primary x-ray beam passes through the patient, some photons are scattered in various directions, which can degrade the quality of the radiographic image by reducing contrast. By placing a grid between the patient and the image receptor, only the primary radiation that travels in a straight line to the receptor is allowed to pass, thus minimizing the amount of scatter radiation that reaches the image detector. This results in improved image quality with greater contrast, allowing for clearer visualization of anatomical structures.

While enhancing detail and improving contrast are significant outcomes of grid use, the fundamental function of the grid is its role in reducing scatter, which directly impacts the radiographic image's clarity and diagnostic value. Increasing patient comfort is not a purpose of grids, as their primary function is purely technical and related to image quality.