Which projection is associated with elongation of the skull when an axial angle is used?

Which projection is associated with elongation of the skull when an axial angle is used?

• A. AP skull with no angle.
• B. Lateral skull.
• C. PA skull.
• D. Anteroposterior (AP) axial Towne skull projection (37-degree angle).

Answer: (D)

Using an axial angle changes the direction of the X-ray beam relative to the skull, so structures that lie along the axis of the projection can appear stretched on the film. The AP axial Towne skull projection uses a caudal angle of about 37 degrees to visualize the occipital region and foramen magnum. That tilt aligns the beam with the length of the skull in a way that makes the skull appear elongated in the image. Non-axial views, like a straight AP skull, a PA skull, or a lateral view, don’t involve that same tilt, so they don’t produce the same elongation. Thus, the projection associated with elongation when an axial angle is used is the AP axial Towne skull projection with the 37-degree angle.

Using an axial angle changes the direction of the X-ray beam relative to the skull, so structures that lie along the axis of the projection can appear stretched on the film. The AP axial Towne skull projection uses a caudal angle of about 37 degrees to visualize the occipital region and foramen magnum. That tilt aligns the beam with the length of the skull in a way that makes the skull appear elongated in the image. Non-axial views, like a straight AP skull, a PA skull, or a lateral view, don’t involve that same tilt, so they don’t produce the same elongation. Thus, the projection associated with elongation when an axial angle is used is the AP axial Towne skull projection with the 37-degree angle.