CAMRT Radiography Practice Exam

How should the central ray be directed for an AP axial projection of the clavicle?

1. Cephalad

2. Caudad

3. Medially

4. Laterally

The correct answer is: Cephalad

For an AP axial projection of the clavicle, the central ray should be directed cephalad. This positioning is essential because it allows for the best visualization of the clavicle's length and curve while minimizing superimposition over the thorax. The cephalad angle typically ranges from 15 to 30 degrees, depending on the patient's anatomy and the specific protocol being followed. This angling helps to project the clavicle above the ribs, highlighting both the bone's structure and its alignment, which is critical for accurate diagnosis and assessment of potential fractures or abnormalities. The direction of the central ray is crucial for proper image interpretation and should always be adjusted in relation to the patient’s posture and the specific projection being performed.