Ohio General X-Ray Machine Operator (GXMO) Practice Exam

Grid cutoff happens when the grid absorbs too much of the primary x-ray beam, causing parts of the image to be underexposed. This usually results from improper grid setup—beam not perpendicular to the grid, the image not centered on the grid, or using the wrong SID or grid focal distance—leading to excessive absorption in certain areas. The effect is visible as lighter or missing density in portions of the image, sometimes with grid lines or bands. The other options don’t describe this specific effect: irregular exposure times change overall density, not a localized cutoff; a perfectly exposed image has no cutoff; and no effect on density contradicts what grid cutoff does.