Radiologic Technologist Practice Exam

Which of the following methods does NOT minimize patient exposure during radiologic procedures?

1. a single-phase generator

2. added tube filtration

3. beam restriction

4. low mAs settings

The correct answer is: a single-phase generator

A single-phase generator is primarily limited in its ability to produce higher quality images at lower exposure levels. When using a single-phase generator, the output is not as consistent as that from a three-phase or high-frequency generator, which can provide more effective use of the x-ray beam and require less dose for the same image quality. This inconsistency can result in higher patient exposure to achieve the necessary diagnostic quality, as more repeat images may be needed. In contrast, added tube filtration helps to remove lower-energy photons from the x-ray beam that do not contribute to the diagnostic image, thereby reducing unnecessary radiation exposure to the patient. Beam restriction limits the size of the x-ray field to the area of interest, focusing the beam on the necessary part of the body and minimizing exposure to surrounding tissues. Lastly, using low mAs settings reduces the overall amount of radiation that the patient is exposed to without sacrificing image quality, as long as the settings are appropriate for the exam. Hence, all these methods, except the single-phase generator, are effective in minimizing patient exposure during radiologic procedures.