At what body-part thickness is the use of a grid recommended?

The use of a grid in radiography is recommended at a body-part thickness of 8 cm or greater. Grids are designed to improve the contrast of the radiographic image by absorbing scattered radiation that occurs as X-rays pass through thicker body parts. When the thickness of the body part being examined increases, the amount of scatter radiation also typically increases, which can degrade the quality of the image.

At 8 cm and above, the likelihood of scatter becomes significant enough that the grid's benefits in enhancing image quality outweigh the added complexity and cost of using them. For body parts less than this thickness, the scatter is minimal, and using a grid may not yield substantial improvement in image quality.

Thus, the recommendation for grid use starts at this threshold to ensure optimal imaging quality for diagnostic purposes.