CAMRT Radiography Practice Exam

Which of the following factors affects motion blur in radiography?

1. OID (Magnification distortion)

2. Patient factors such as shape and position

3. SID (Distance from source to image receptor)

4. Focal spot size

The correct answer is: Patient factors such as shape and position

Motion blur in radiography primarily occurs due to the relative movement between the patient and the image receptor during the exposure. Patient factors such as shape and position play a crucial role in this context. For instance, if a patient cannot remain still or if their anatomical features are positioned in a way that does not maintain alignment with the image receptor, this can lead to misrepresentations on the radiographic image. In practice, if a patient's position changes during the exposure time—even slightly—this motion is recorded, resulting in blurring. Therefore, understanding how to stabilize the patient and ensuring they are positioned correctly is vital to minimizing motion blur in radiographic images. While other factors mentioned, such as OID, SID, and focal spot size, do influence the clarity and quality of images, it is the patient’s motion that directly contributes to motion blur specifically.