Critique 1 - Lateral C-Spine

Practice questions and answers focusing on the technical critique, anatomy, and image quality of a horizontal-beam lateral cervical spine radiograph.

What specific projection and anatomical part is demonstrated in this image critique?

A left horizontal-beam (HB) lateral cervical spine.

Which anatomical structures must be visible for a lateral cervical spine image to be considered complete?

The base of skull, all 7 cervical vertebrae, and at least the superior 1/3 of T1.

Which structures are clearly visualized in this image, and which are obscured?

The base of skull and C1–C5 are clearly visualized, while C6–T1 are obscured by the shoulders.

What specific additional projection is required to demonstrate the C7–T1 junction when it is obscured?

A Swimmer's lateral projection.

Where is the central point (CP) positioned in this image, and is it correct?

The CP is at the level of C4 but is positioned too posteriorly by approximately $1\frac{1}{2}$–$2$ marker widths.

How is tilt assessed on a lateral cervical spine radiograph?

By assessing superior/inferior separation of the zygapophyseal (z-) joints.

How is cervical spine rotation assessed on a lateral radiograph?

By looking for anterior/posterior separation of the z-joints.

What evidence in the image suggests that the head or mandible is rotated?

The right mandibular ramus appears superimposed over the anterior aspect of C2.

Why can the beam-to-part (BTP) angle not be adequately assessed in this image?

There is insufficient visible collimation border to reliably assess the beam angle.

What radiographic findings suggest that a higher-than-required kVp may have been used?

The anterior and posterior soft tissues appear burned out, and the cervical vertebral bodies lack clear trabecular detail.

Where is radiographic noise most evident in this image?

From approximately C6 inferiorly.

What was the error regarding the placement of the left anatomical marker?

The marker was placed outside the radiation field and required annotation afterward.

What image receptor (IR) size and orientation were used for this examination?

An IR size of $23 \times 30\,cm$ was used, oriented with its long axis aligned with the long axis of the cervical spine.

What radiographic evidence demonstrates that there was no patient motion?

The cortical bone margins appear sharp without motion blurring.

Which items are considered non-removable foreign bodies in this specific trauma situation?

The dental filling, sheets, transfer device/mattress, cervical collar, and clothing overlying C5.