To minimize patient dose in pediatric radiography, which grid characteristic is preferred?

• A. Low ratio, rapidly moving
• B. High ratio, rapidly moving
• C. Stationary fine-line
• D. High ratio, stationary

Answer: (A)

To minimize patient dose, use a grid that balances scatter control with the least attenuation of the primary beam, and add motion to prevent grid-line artifacts. A low-ratio grid attenuates less of the primary beam, so you can achieve the needed image receptor exposure at a lower dose. Pairing that with rapid grid motion keeps grid lines from appearing on the image, so you don’t have to increase exposure to cover or hide those artifacts. In contrast, a high-ratio grid reduces more scatter but requires more exposure and delivers more dose, and a stationary grid risks grid-line artifacts that can necessitate higher exposure or image rejection. So the best choice is a low-ratio grid that moves rapidly.