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Medicine

MRI Physics and Artifact Recognition in Clinical Imaging

Quick fact

MRI images are not photographs; they are maps of how hydrogen protons in water and fat relax after being excited by radio waves, and a single 'slice' is actually built from millions of tiny signals that are mathematically reconstructed.

Why this is interesting

You've seen stunning MRI images of the brain—but have you ever wondered why sometimes a black smudge appears where there's a metal filling, or why flowing blood can look completely different in the same scan?