Critical Care Registered Nurse (CCRN) Practice Exam

What is the purpose of instructing a patient to lie still during a PET scan?

1. To prevent discomfort during the procedure

2. To ensure accurate imaging results

3. To allow for easier insertion of the I.V.

4. To minimize anxiety related to the test

The correct answer is: To ensure accurate imaging results

The purpose of instructing a patient to lie still during a PET scan is to ensure accurate imaging results. During a PET scan, the patient is exposed to radioactive tracers, which emit positrons that are detected by the scanner to create detailed images of the body's metabolic activity. Any movement, such as shifting or fidgeting, can blur the images and compromise the quality and diagnostic value of the scan. By remaining still, the patient helps to provide clear, precise images, allowing for better assessment and diagnosis by the healthcare team. In contrast, minimizing discomfort, facilitating IV insertion, or reducing anxiety are important considerations in patient care, but they do not directly relate to the primary purpose of remaining still during the scanning process itself.