Grid ratio is defined as

Grid ratio is defined as

• A. Height by width
• B. Number of lead strips per inch
• C. Distance from tube to patient
• D. Film-speed category

Answer: (A)

Grid ratio describes how tall the lead strips are relative to the width of the spaces between them. It’s calculated by dividing the height of the lead strips by the interspace width (the space between strips). This is often expressed as a ratio like 8:1 or 12:1. A higher ratio means more scatter is absorbed and image contrast improves, but more X-ray exposure is needed to maintain the same image brightness. The idea that the ratio is height by width fits this definition exactly. The other options refer to how many strips exist per inch (grid frequency), the distance from tube to patient (SID), or the film-screen system speed, none of which define the grid’s ratio.

Grid ratio describes how tall the lead strips are relative to the width of the spaces between them. It’s calculated by dividing the height of the lead strips by the interspace width (the space between strips). This is often expressed as a ratio like 8:1 or 12:1. A higher ratio means more scatter is absorbed and image contrast improves, but more X-ray exposure is needed to maintain the same image brightness. The idea that the ratio is height by width fits this definition exactly. The other options refer to how many strips exist per inch (grid frequency), the distance from tube to patient (SID), or the film-screen system speed, none of which define the grid’s ratio.