Grid Radius is defined as

Grid Radius is defined as

• A. Distance to which grid lines are focused and the SID at which the grid should be used
• B. Height of lead strips divided by distance between strips
• C. Number of lead strips per inch
• D. The material of the grid

Answer: (A)

Grid radius is the distance to which the grid lines are focused and the SID at which the grid should be used. For focused grids, the lead strips are angled to match the divergent X-ray beam from the focal spot, so the grid works best when the imaging setup matches this designed distance. Using the grid at that specified SID minimizes grid cut-off and uneven exposure at the edges. This concept is distinct from grid ratio (the height of the lead strips divided by the interspace), grid frequency (how many lead strips per inch), or the grid material (what the grid is made of). So the grid radius defines the intended focal distance and the corresponding SID for optimal performance.

Grid radius is the distance to which the grid lines are focused and the SID at which the grid should be used. For focused grids, the lead strips are angled to match the divergent X-ray beam from the focal spot, so the grid works best when the imaging setup matches this designed distance. Using the grid at that specified SID minimizes grid cut-off and uneven exposure at the edges. This concept is distinct from grid ratio (the height of the lead strips divided by the interspace), grid frequency (how many lead strips per inch), or the grid material (what the grid is made of). So the grid radius defines the intended focal distance and the corresponding SID for optimal performance.