A patient should be positioned with what two points of their anatomy touching the IR for a PA projection of the skull?

A patient should be positioned with what two points of their anatomy touching the IR for a PA projection of the skull?

• A. Chin and nose
• B. Forehead and chin
• C. Occiput and ears
• D. Forehead and nose

Answer: (D)

The key idea is to position the skull so that its anterior surface lies flat against the image receptor, giving a true PA orientation. For a PA skull projection, you want the front of the head—the forehead and the nasal bridge—to contact the IR. This broad, stable contact keeps the skull parallel to the receptor, minimizes distortion and magnification of facial structures, and helps ensure the central ray passes perpendicular through the midline. If the chin and nose, or the occiput and ears, were the points in contact, the skull would be tilted or rotated relative to the IR, which would distort the projection and magnify/analyze different parts unevenly. Forehead and nose contact provides the most reliable, stable alignment for this view.

The key idea is to position the skull so that its anterior surface lies flat against the image receptor, giving a true PA orientation. For a PA skull projection, you want the front of the head—the forehead and the nasal bridge—to contact the IR. This broad, stable contact keeps the skull parallel to the receptor, minimizes distortion and magnification of facial structures, and helps ensure the central ray passes perpendicular through the midline.

If the chin and nose, or the occiput and ears, were the points in contact, the skull would be tilted or rotated relative to the IR, which would distort the projection and magnify/analyze different parts unevenly. Forehead and nose contact provides the most reliable, stable alignment for this view.