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Testing and Performance Requirements for MR Receive-Only Coils for General Diagnostic Use

This guidance covers MR receive-only coils intended for hydrogen/proton imaging with no patient contact or limited contact with intact skin. The devices should be air-cooled and designed for general diagnostic use. The guidance excludes coils for specific clinical indications, new imaging agents, or endocavity coils.

  1. Conduct all required performance testing according to specified standards
  2. Obtain clinical image review from qualified physician
  3. Perform biocompatibility evaluation or provide rationale for exemption
  4. Prepare comprehensive test documentation including:
    • Results summaries
    • Declarations of Conformity
    • Circuit diagrams
    • Clinical image samples
    • Biocompatibility documentation
  5. Consider Pre-Submission if additional testing beyond guidance scope is needed
  6. Ensure all temperature and safety limits are met
  7. Document decoupling mechanisms
  8. Prepare EMC and electrical safety testing documentation

Key Considerations

Clinical testing

  • Sample clinical images must be reviewed by a US Board Certified or international equivalent qualified physician
  • Images must be of diagnostic quality for all target anatomical locations

Non-clinical testing

  • Image Signal to Noise (SNR) requirements: >130 for 1.5T coils, >215 for 3T coils
  • Image Uniformity: Worst-case non-uniformity < 50%
  • Surface heating: Temperature < 41°C for both normal use and single fault conditions
  • Decoupling circuit must be present and documented
  • EMC testing: pass at ±8 kV contact, ±2 kV, ±4 kV, ±8 kV, ± 15 kV air
  • General electrical/mechanical safety testing required

Biocompatibility

  • Required testing for surface devices with intact skin contact ≤24 hours:
    • Cytotoxicity
    • Sensitization
    • Irritation or Intracutaneous Reactivity

Safety

  • Must comply with electrical safety standards
  • Temperature limits must be maintained
  • Decoupling mechanisms must be present

Other considerations

  • IEC 62464-1: Magnetic resonance equipment for medical imaging - Part 1: Determination of essential image quality parameters
  • NEMA MS 1: Determination of Signal-to-Noise Ratio (SNR) in Diagnostic Magnetic Resonance Imaging
  • NEMA MS 6: Determination of Signal-to-Noise Ratio and Image Uniformity for Single-Channel, Non-Volume Coils
  • NEMA MS 9: Characterization of Phased Array Coils for Diagnostic Magnetic Resonance Images
  • NEMA MS 14: Characterization of Radiofrequency (RF) Coil Heating
  • IEC 60601-1-2: Medical electrical equipment – EMC requirements
  • AAMI/ANSI ES60601-1: Medical electrical equipment - General Requirements for Basic Safety
  • IEC 60601-2-33: Particular requirements for MR equipment safety
  • ISO 10993-1: Biological evaluation of medical devices

Original guidance

  • Testing and Performance Requirements for MR Receive-Only Coils for General Diagnostic Use
  • HTML / PDF
  • Issue date: 2020-12-11
  • Last changed date: 2020-12-10
  • Status: FINAL
  • Official FDA topics: Radiation-Emitting Products, Medical Devices, 510(k), Premarket, Radiology
  • ReguVirta summary file ID: 2ebf4acf79a476930a33645939fe1b51
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