Practical Tips and Tricks for Salvaging ECG-gated Cardiac CT from Motion Artifacts.

Area of Science:

• Medical Imaging
• Radiology
• Cardiovascular Imaging

Background:

• Motion artifacts are common in cardiac CT, impacting image quality despite technical advances.
• These artifacts can arise from patient motion, breathing, or cardiac dynamics.
• While some artifacts necessitate repeat scans, others are correctable.

Purpose of the Study:

• To review and categorize common cardiac motion artifacts in CT.
• To discuss mitigation strategies for various artifact types without repeating scans.
• To highlight the role of electrocardiographic (ECG) synchronization in artifact correction.

Main Methods:

• Categorization of cardiac motion artifacts into blur, transition, interpolation, and duplication.
• Description of artifact causes related to scanner parameters and patient physiology.
• Explanation of mitigation techniques including cardiac phase selection, motion-correction algorithms, and ECG sync-point manipulation.

Main Results:

• Blur artifacts are mitigated by adjusting cardiac phase, using motion-correction algorithms, or multisegment reconstruction.
• Transition artifacts can be addressed by altering cardiac phase or employing edge-correction algorithms.
• Interpolation and duplication artifacts are often resolved by editing or composing ECG sync-points, especially in cases of arrhythmias.

Conclusions:

• Cardiac motion artifacts, though common, can be effectively managed through various techniques.
• Specific strategies exist for blur, transition, interpolation, and duplication artifacts.
• ECG sync-point manipulation is a key method for correcting interpolation and duplication artifacts, improving cardiac CT image quality.