Which statement about grid use in radiography is correct?

Which statement about grid use in radiography is correct?

• A. Grid reduces scatter and increases contrast
• B. Grid increases scatter
• C. Grid reduces resolution
• D. Grid increases patient dose with no benefit

Answer: (A)

Scatter produced in the patient lowers image contrast, so the grid’s job is to absorb many of those scattered photons before they reach the detector, while still letting through the primary photons along the beam. This selective absorption leaves more of the useful signal and less unwanted background, which increases image contrast. Because the grid also absorbs some primary radiation, technique often must be increased to maintain receptor exposure, which can raise the patient dose a bit—but the trade-off is clearer, more diagnostic detail. The idea that grids increase scatter is incorrect; they reduce scatter. Grids do not inherently reduce resolution; most changes in resolution come from other factors like focal spot size, motion, or detector characteristics, not the grid itself.

Scatter produced in the patient lowers image contrast, so the grid’s job is to absorb many of those scattered photons before they reach the detector, while still letting through the primary photons along the beam. This selective absorption leaves more of the useful signal and less unwanted background, which increases image contrast. Because the grid also absorbs some primary radiation, technique often must be increased to maintain receptor exposure, which can raise the patient dose a bit—but the trade-off is clearer, more diagnostic detail. The idea that grids increase scatter is incorrect; they reduce scatter. Grids do not inherently reduce resolution; most changes in resolution come from other factors like focal spot size, motion, or detector characteristics, not the grid itself.