Which device reduces scattered radiation produced in the patient but increases the dose to the patient?

Which device reduces scattered radiation produced in the patient but increases the dose to the patient?

• A. Collimation
• B. Filtration
• C. Grid
• D. Table bucky

Answer: (C)

The main concept is that a grid improves image contrast by absorbing scattered photons before they reach the image receptor, but those lead strips also attenuate some primary photons. To maintain the same receptor exposure after placing a grid, you must increase the exposure (mAs). That higher exposure raises the patient’s dose, so a grid reduces scatter yet increases patient dose. The amount of dose increase depends on the grid’s ratio and design—the higher the grid ratio, the larger the needed exposure boost. The other devices don’t inherently cause this trade-off: collimation reduces beam size and scatter (often lowering dose), filtration removes low-energy photons (reducing dose), and the table bucky mainly provides mechanical support for the grid and film; it doesn’t itself drive the higher exposure needed to compensate for grid attenuation.

The main concept is that a grid improves image contrast by absorbing scattered photons before they reach the image receptor, but those lead strips also attenuate some primary photons. To maintain the same receptor exposure after placing a grid, you must increase the exposure (mAs). That higher exposure raises the patient’s dose, so a grid reduces scatter yet increases patient dose. The amount of dose increase depends on the grid’s ratio and design—the higher the grid ratio, the larger the needed exposure boost. The other devices don’t inherently cause this trade-off: collimation reduces beam size and scatter (often lowering dose), filtration removes low-energy photons (reducing dose), and the table bucky mainly provides mechanical support for the grid and film; it doesn’t itself drive the higher exposure needed to compensate for grid attenuation.