CLINICAL MEDICINE

Detailed explanation-1: -mAs stands for milli-ampere-second. It determines how many x-ray photons are produced (quantity). It has no effect on the strength (penetrating power) of the x-ray photons. mAs is a product of multiplying two factors together: time and milliamperage (mA).

Detailed explanation-2: -Milliamperes (mA) is a unit representing the amount of current passed through the X-ray tube. Current determines the number of photons produced by the X-ray tube, also known as X-ray quantity. [12] Another contributing factor toward X-ray quantity is the total exposure time, measured in seconds.

Detailed explanation-3: -First calculate 10% of 80 which is 8, then divide that by 2 to get 5% of 80 (8/2=4). Then we add 8+4=12, which is 15% of 80. Since 92 is 12 higher than 80 we see that the kVp has been increased by 15%. Therefore, we need to divide the mAs by 2 to get the new mAs (50 mAs /2 = 25 mAs).

Detailed explanation-4: -The increase in x-ray tube voltage increases the amount of radiation coming out of the x-ray tube, as well as the average photon energy (i.e., increased penetration). Accordingly, the tube current exposure time product value (mAs) is reduced to 36 mAs; whereas at 60 kV, the value was much higher (141 mAs).