American Society of Radiologic Technologist (ASRT) Practice Exam 2025 – All-in-One Guide for Exam Success!

For an AP (anterior-posterior) chest X-ray, the patient is typically positioned standing or seated upright. This positioning is crucial as it helps to obtain clear images of the thoracic cavity, which includes the heart, lungs, and large blood vessels. When the patient is upright, gravity helps to ensure that the diaphragm is in its lowest position, which aids in the full expansion of the lungs and enhances the visibility of any potential abnormalities.

In this position, the air-filled structures of the lungs can be more easily differentiated from surrounding tissues. Additionally, it reduces the potential for superimposition of anatomical structures, providing a more accurate representation of the thoracic organs.

While other positions, such as supine or prone, might be used in specific situations (like in trauma cases or for patients who cannot stand), the upright position is favored for a standard AP chest X-ray due to the advantages it provides for imaging.