Final answer:
To adjust CR for a portable Chest X-Ray on a kyphotic patient, you should decrease the CR angle and align the CR parallel to the tabletop.
Step-by-step explanation:
When adjusting the CR (central ray) for a portable Chest X-Ray on a kyphotic patient, you should decrease the CR angle. The CR angle is the angle at which the X-ray beam is directed towards the patient. By decreasing the CR angle, you can better align the X-ray beam with the patient's anatomy, ensuring a more accurate image.
In addition to decreasing the CR angle, it is also important to align the CR parallel to the tabletop. By doing so, you can minimize distortions caused by the curvature of the patient's spine and obtain a clearer image of the chest.
Overall, the goal is to make adjustments that accommodate the kyphotic patient's anatomy and minimize any potential issues that may arise due to the curvature of the spine.