How does patient motion affect image quality, and what strategies reduce motion artifacts?

How does patient motion affect image quality, and what strategies reduce motion artifacts?

• A. Motion improves image sharpness.
• B. Motion causes blur and reduced sharpness; mitigate with shorter exposure times, immobilization, clear instructions, and prompt acquisition.
• C. Motion has no effect on digital radiography.
• D. Motion artifacts can be completely corrected in post-processing.

Answer: (B)

Motion during exposure causes blur and reduced sharpness because the anatomy moves while the detector is recording photons. The image is formed over the exposure time, so any movement smears edges and lowers spatial resolution. To reduce motion artifacts, use shorter exposure times to shrink the window in which movement can occur, apply immobilization or supports to physically restrict movement, give clear instructions so the patient knows to stay still and, when appropriate, hold a breath, and perform the exposure promptly to minimize the time between positioning and exposure. In digital radiography, motion artifacts degrade detail and are not fully correctable in post-processing, so prevention through technique and patient management is preferred. The other options miss the reality that motion harms sharpness, affects digital systems, and cannot be completely corrected after the fact.

Motion during exposure causes blur and reduced sharpness because the anatomy moves while the detector is recording photons. The image is formed over the exposure time, so any movement smears edges and lowers spatial resolution. To reduce motion artifacts, use shorter exposure times to shrink the window in which movement can occur, apply immobilization or supports to physically restrict movement, give clear instructions so the patient knows to stay still and, when appropriate, hold a breath, and perform the exposure promptly to minimize the time between positioning and exposure. In digital radiography, motion artifacts degrade detail and are not fully correctable in post-processing, so prevention through technique and patient management is preferred. The other options miss the reality that motion harms sharpness, affects digital systems, and cannot be completely corrected after the fact.