Question

A particular radiograph was produced using 12 mAs and 85 kV with a 16:1 ratio grid. The radiograph is to be repeated using an 8:1 ratio grid. What should be the new milliampere-seconds value?

8

Answer 1

To calculate the new milliampere-seconds (mAs) value, we use the mAs reciprocity principle and set up an equation based on the initial mAs value and grid ratios. After solving the equation, we find that the new mAs should be 24.

Step-by-step explanation:

To calculate the new milliampere-seconds (mAs) value, we need to use the mAs reciprocity principle, which states that the product of milliamperes (mA) and seconds (s) should remain constant when changing the grid ratio. In this case, we have an initial mAs of 12 and a grid ratio of 16:1. To find the new mAs value with an 8:1 ratio grid, we can set up the following equation:

initial_mAs * initial_ratio = new_mAs * new_ratio

12 * 16 = new_mAs * 8

192 = new_mAs * 8

new_mAs = 192 / 8 = 24

Therefore, the new milliampere-seconds value should be 24.