AAPM/RSNA physics tutorial for residents: MR artifacts, safety, and quality control.

Area of Science:

• Medical Imaging Physics
• Radiology

Background:

• Magnetic Resonance (MR) imaging artifacts arise from complex interactions within imager subsystems.
• Advancements in MR technology, including higher field strengths and multiple RF channels, necessitate a focus on safety.

Purpose of the Study:

• To highlight the sources of MR imaging artifacts.
• To emphasize the importance of understanding biologic effects and physical safety in MR imaging.
• To recommend quality assurance measures for MR systems.

Main Methods:

• Review of MR imaging system components and their contribution to artifacts.
• Discussion of biologic effects of magnetic fields, acoustic noise, and radiofrequency (RF) energy.
• Emphasis on equipment testing, monitoring, and accreditation programs.

Main Results:

• Artifacts are a result of interactions between magnets, gradient coils, RF systems, and reconstruction algorithms.
• Increased MR field strengths and RF channels require attention to potential physiologic effects and safety.
• Regular equipment checks and physicist evaluations are vital for stable MR functioning.

Conclusions:

• Awareness of artifact sources aids in optimizing MR imaging performance.
• Radiologists must be cognizant of potential patient safety issues and implement accident prevention strategies.
• Implementing a robust quality assurance program, including accreditation, is recommended for all MR imaging facilities.