What is the equation for calculating grid ratio?

The grid ratio is an important concept in radiography, particularly in the use of grids to enhance image contrast by reducing scatter radiation. The grid ratio is defined as the height of the lead strips in the grid divided by the width of the interspace material that separates these lead strips.

This relationship is crucial because it determines how effective the grid will be at filtering out scatter radiation. A higher grid ratio means that the lead strips are taller relative to the spacing between them, which increases the grid's ability to absorb scatter radiation while allowing the primary radiation to pass through. Consequently, option B, which states that the grid ratio equals the height divided by the width of the interspace, accurately captures this definition and mathematical relationship.

Understanding the grid ratio's formula helps radiologic technologists select the appropriate grid for various imaging situations, ensuring optimal image quality and patient safety.