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Technical Performance Assessment of Digital Whole Slide Imaging Systems in Anatomic Pathology

This guidance provides recommendations for technical performance assessment data required for regulatory evaluation of digital Whole Slide Imaging (WSI) systems used in surgical pathology. It covers: - Image acquisition subsystems that convert glass slides into digital image files - Workstation environments for viewing digital images - Technical performance assessment at component and system levels - Does NOT cover special stain techniques, fluorescence imaging, non-technical analytical studies, or pivotal clinical studies - Does NOT cover mobile platforms interpretation

  1. Develop comprehensive technical documentation covering all components and systems
  2. Implement testing protocols for:
    • Component level performance
    • System level performance
    • Color reproducibility
    • Spatial resolution
    • Focus quality
    • Tissue coverage
    • Stitching accuracy
  3. Conduct human factors validation testing:
    • Define user populations
    • Identify critical tasks
    • Create simulated use conditions
    • Document results
  4. Establish quality control procedures:
    • Define testing methods
    • Set quantitative action limits
    • Create quality control manual
  5. Prepare complete labeling package:
    • Instructions for use
    • Service instructions
    • Warnings
    • Training materials
  6. Document risk management:
    • Identify hazards
    • Assess risks
    • Implement controls
    • Monitor effectiveness
  7. Validate software components:
    • Image processing
    • Image review
    • Quality control
    • System performance

Key Considerations

Non-clinical testing

  • Component level testing for each part of the imaging chain (slide feeder, light source, optics, scanner, sensor, etc.)
  • System level testing including:
    • Color reproducibility assessment
    • Spatial resolution evaluation
    • Focus quality testing
    • Whole slide tissue coverage verification
    • Stitching error assessment
    • Turnaround time measurement

Human Factors

  • Human factors/usability validation testing required
  • Test with representative users under simulated conditions
  • Evaluate critical tasks and use scenarios
  • Consider user capabilities, expectations and fatigue
  • Assess workstation ergonomics and environmental factors

Software

  • Image processing software requirements
  • Image review manipulation software capabilities
  • Quality control procedures and testing methods
  • Software validation according to FDA guidance

Labeling

  • Must satisfy 21 CFR Part 801 and 21 CFR 809.10
  • Include detailed instructions for use, servicing, warnings
  • Labeling studies separate from usability testing
  • Final version required for validation testing

Safety

  • Risk analysis and management required
  • Use-related hazards identification
  • Risk mitigation strategies
  • Quality control procedures

Other considerations

  • ISO 14971:2007: Medical Devices – Application of Risk Management to Medical Devices
  • AAMI/ANSI HE75:2009: Human Factors Engineering – Design of Medical Devices
  • IEC 62366-1:2015: Medical devices – Application of usability engineering to medical devices
  • ISO 12233:2014(E): Photography — Electronic still picture imaging — Resolution and spatial frequency responses
  • ISO 8039:2014: Optics and optical instruments — Microscopes — Magnification
  • ISO 13653:1996: Optics and optical instruments – General optical test methods
  • ISO 9039:2008: Optics and photonics — Quality evaluation of optical systems
  • ISO 15795:2002: Optics and optical instruments — Quality evaluation of optical systems
  • ISO 230-2:2014: Test code for machine tools —Part 2: Determination of accuracy and repeatability

Original guidance

  • Technical Performance Assessment of Digital Whole Slide Imaging Systems in Anatomic Pathology
  • HTML / PDF
  • Issue date: 2016-04-20
  • Last changed date: 2019-03-28
  • Status: FINAL
  • Official FDA topics: Medical Devices, Laboratory Tests, 510(k), Labeling, Premarket, IVDs (In Vitro Diagnostic Devices)
  • ReguVirta summary file ID: abd3a98d61a40e71105bd7d42e397cad
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