Question

In computed tomography, if the pitch increases, the dose?

a. Pitch and dose are unrelated
b. Increases
c. Stays the same, as dose is controlled by mAs and kV
d. Decreases

Answer 1

In computed tomography, as the pitch increases, the patient's radiation dose decreases because the table moves faster, resulting in fewer overlapping x-rays.

Step-by-step explanation:

In computed tomography (CT), the concept of pitch is related to the speed at which the scanning table moves compared to the rotation of the CT scanner. If the pitch increases, this means the table is moving faster during the scan, resulting in fewer overlapping x-rays and consequently a lower radiation dose to the patient. Therefore, if the pitch increases, the dose decreases. This is because the dosage is primarily controlled by factors such as milliampere-seconds (mAs) and kilovoltage (kV), not the pitch; however, changing the pitch can affect the level of overlap of the X-ray beam through the patient and result in a modified dose received.