In a cross-table lateral cervical spine radiograph with a horizontal beam, which vertebral level should the central beam be centered on?

In a cross-table lateral cervical spine radiograph with a horizontal beam, which vertebral level should the central beam be centered on?

• A. C3
• B. C5
• C. C4
• D. C2

Answer: (C)

Center the central ray at the level of the thyroid cartilage in the midneck. This landmark sits at roughly the midpoint of the cervical spine, so directing the beam there puts the vertebral bodies of the entire cervical region near the center of the image and ensures the view includes C1 through the upper thoracic area. With a horizontal beam, this alignment minimizes distortion and helps the dens, the upper cervical joints, and the lower cervical levels stay within the field of view. If the beam is centered too high, the lower cervical levels can be clipped; if centered too low, the upper cervical structures may be truncated.

Center the central ray at the level of the thyroid cartilage in the midneck. This landmark sits at roughly the midpoint of the cervical spine, so directing the beam there puts the vertebral bodies of the entire cervical region near the center of the image and ensures the view includes C1 through the upper thoracic area. With a horizontal beam, this alignment minimizes distortion and helps the dens, the upper cervical joints, and the lower cervical levels stay within the field of view. If the beam is centered too high, the lower cervical levels can be clipped; if centered too low, the upper cervical structures may be truncated.