Artifact (medical imaging)

Artifacts are misrepresentations of tissue structures seen in medical images produced by modalities such as  Ultrasonography, X-ray Computed Tomography, and Magnetic Resonance Imaging. These artifacts are caused by a variety of mechanisms, such as:The underlying physics of the energy-tissue interaction (ie: Ultrasound-air)Data acquisition errors (mostly from patient motion)A reconstruction algorithm's inability to represent the anatomy. Physicians learn to recognize these artifacts to avoid confusing them with real pathology.
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