American Society of Radiologic Technologist (ASRT) Practice Exam

Minimizing patient exposure occurs when all of the following EXCEPT ________ are done.

1. adding contrast medium

2. reducing the mAs

3. adding filtration

4. reducing the object-to-image distance (OID)

The correct answer is: adding contrast medium

Minimizing patient exposure is a critical principle in radiologic procedures aimed at protecting patients while still obtaining high-quality images. Among the choices, adding contrast medium does not contribute to reducing radiation exposure. In fact, the use of contrast materials generally serves to enhance the visibility of anatomical structures on the images, which may not necessarily correlate with a reduction in exposure levels. In contrast, reducing the mAs (milliampere-seconds) directly decreases the amount of radiation used during the imaging process, thereby lowering the patient’s dose. Increasing filtration also enhances image quality by reducing the low-energy, less penetrating radiation which contributes to dose without improving image quality, helping to minimize patient exposure. Maintaining an appropriate object-to-image distance (OID) is essential in radiology. A reduced OID actually increases the radiation dose to the patient because it can lead to increased magnification and scatter, but the intent behind proper management of OID is to optimize image clarity rather than directly influence exposure levels. Therefore, among the options provided, adding contrast medium is the procedure that does not inherently contribute to minimizing patient exposure. It can improve the diagnostic quality of images while potentially increasing the overall dose due to the need for additional imaging techniques or higher doses to visualize contrast-filled structures effectively