Final answer:
The perpendicular beam technique should be used only in certain situations when it is necessary to obtain an accurate representation of the body's internal structures without distortion, mainly in diagnostic imaging such as radiography.
Step-by-step explanation:
The perpendicular beam technique should be used only in certain situations. This technique is typically utilized in diagnostic imaging, such as radiographs, to reduce the distortion of the image and provide a clear view of the structure being examined. It ensures that the central ray of the beam is perpendicular to the object and the image receptor. By doing so, this technique helps to produce an image that faithfully represents the actual dimensions and positions of the structures within the body.
For instance, when performing a chest radiograph, the perpendicular beam technique is crucial for an accurate representation of the chest cavity, as angulation can lead to misinterpretation. However, there are some clinical situations where alternative angulation is necessary to visualize certain anatomical structures better. Therefore, it's not appropriate to use the perpendicular beam technique always or whenever possible, but rather when it is the best option to achieve the diagnostic goal.