What is the impact of higher grid ratios on radiographic images?

Higher grid ratios have a significant impact on the quality of radiographic images by effectively reducing scatter radiation. Grids are used in radiography to enhance image contrast by absorbing scatter that originates from the patient. A higher grid ratio means that the strips of lead in the grid are more closely spaced, which allows them to absorb more of the scattered photons while allowing the primary radiation to pass through to the imaging receptor.

However, because higher grid ratios are more efficient at attenuating scatter, they may also necessitate an increase in exposure to achieve sufficient image density. This is required because less primary radiation will reach the detector due to the increased absorption by the grid. Therefore, when utilizing high grid ratios, radiographers often need to adjust their exposure settings, such as increasing the milliampere-seconds (mAs) or kilovoltage peak (kVp), to ensure optimal image quality is maintained. As a result, the use of higher grid ratios can indeed reduce scatter more effectively while potentially requiring a higher exposure to produce images with the desired contrast and density.