Elongation and foreshortening are examples of:

Elongation and foreshortening are examples of:

• A. Size distortion
• B. Shape distortion
• C. Motion
• D. Distortion caused by short SID and long OID

Answer: (B)

Elongation and foreshortening tell you about changes in the appearance of an object's shape on an image. They occur when the x-ray beam, the part, and the image receptor aren’t aligned so the structure’s long axis isn’t captured perpendicularly. The result is a silhouette that looks stretched (elongation) or compressed (foreshortening) even though the actual size hasn’t changed. This is why they’re classified as shape distortion. Motion would cause blur, and pure magnification is a size change due to distance, not a shape change. Distortion from SID/OID can affect the image, but elongation and foreshortening specifically describe altered shape.

Elongation and foreshortening tell you about changes in the appearance of an object's shape on an image. They occur when the x-ray beam, the part, and the image receptor aren’t aligned so the structure’s long axis isn’t captured perpendicularly. The result is a silhouette that looks stretched (elongation) or compressed (foreshortening) even though the actual size hasn’t changed. This is why they’re classified as shape distortion. Motion would cause blur, and pure magnification is a size change due to distance, not a shape change. Distortion from SID/OID can affect the image, but elongation and foreshortening specifically describe altered shape.