Which option best reduces distortion by proper setup?

• A. Receptor alignment alone
• B. Beam alignment alone
• C. Patient positioning only
• D. Proper receptor and beam alignment

Answer: (D)

Distortion comes from the geometry of the setup: if the beam, receptor, or the anatomy aren’t aligned just right, sizes and shapes on the image won’t match reality. The best way to minimize distortion is to coordinate both receptor alignment and beam alignment with the anatomy. When the receptor sits parallel to the anatomy and the central ray is directed perpendicular to both, the image suffers less foreshortening and magnification, showing true size and shape. If you fix only the receptor or only the beam, a misalignment in the other element still causes distortion. While patient positioning matters, it doesn’t eliminate distortion on its own unless the beam and receptor are also correctly aligned.