Most artifacts are fixable in post-processing. The few that aren’t (breathing) just mean the scan needs to be redone.
Recognition: noticeable step-off that involves the sternum/ribs alongside the heart.
Fix: cannot be fixed in post-processing — rescan the patient with better breath-hold instructions.
Recognition: step-off that does not involve the sternum — heart-only misalignment.
Fix: reconstruct the dataset at different cardiac phases.
Recognition: blurring or a crescent shape in a vessel (classically the RCA).
Fix: reconstruct at a different cardiac phase (mid-diastole or end-systole), or use a wider temporal window.
Recognition: dark hypoattenuated spots and bright radial streaks caused by high-density materials — pacemaker leads (especially the RA lead next to the RCA) absorbing low-energy photons.
Fix: high-energy X-rays or high-energy virtual monoenergetic images.
Recognition: extensive calcified plaques or stents visually “bloom” and obscure the lumen — leading to false-positive overestimation of stenosis.
Fix: reconstruct with thinner slices, sharper kernels, or iterative reconstruction (at the cost of higher noise).