Retinal Prostheses: Clinical, Non-Clinical, and Safety Recommendations for Electrical Stimulation Devices
This guidance is specifically focused on retinal prostheses that are implanted on or beneath the retina, or on/beneath the outer surface of the globe, using electrical stimulation to provide visual perception for people with degenerative retinal conditions. It does not apply to prostheses that stimulate the optic nerve, visual cortex, or other brain areas.
Recommended Actions
- Develop comprehensive pre-clinical testing plan including animal studies, durability testing, and biocompatibility evaluation
- Design clinical protocol with:
- Clear inclusion/exclusion criteria
- Defined safety and effectiveness endpoints
- Statistical analysis plan
- Long-term follow-up strategy
- Create detailed device description documentation including:
- Engineering drawings
- Material specifications
- Software documentation
- Manufacturing process description
- Establish risk management process and documentation
- Develop complete labeling package including:
- Surgical procedure
- Warnings and precautions
- Patient information
- Training materials
- Create sterilization validation protocol
- Prepare IDE submission package with all required elements
- Consider requesting Pre-Submission meeting with FDA to discuss study design and requirements
Key Considerations
Clinical testing
- Follow subjects for minimum 3 years
- Evaluate visual performance at intervals of max 3 months for first year, max 6 months thereafter
- Include assessments of:
- Visual function (acuity, grating, spatial mapping)
- Functional vision in real-world situations
- Patient reported outcomes
- Use independent professionals for orientation/mobility assessments
- Include statistical analysis plan with sample size justification
Non-clinical testing
- Conduct animal testing on active finished device before human trials
- Perform acute tests (24h) and long-term tests (6+ months) in animal models
- Evaluate histology and device functionality post-explantation
- Conduct accelerated lifetime tests for durability
- Validate welding/bonding processes
- Test flexion under simulated use conditions
Human Factors
- Evaluate usability of portable controller
- Assess tactile controls and indicators
- Consider impact resistance and water resistance
- Ensure ease of battery replacement
- Validate all patient and clinician software
Software
- Describe physician fitting software and patient controls
- Include fail-safes and protection against programming errors
- Validate software according to level of concern
- Include resets/presets and device feedback mechanisms
Labelling
- Include contraindications, warnings, precautions
- Describe surgical procedure in detail
- Provide patient information and implant card
- Include electromagnetic compatibility warnings
- Detail storage conditions and battery information
Biocompatibility
- Provide material biocompatibility profiles
- Conduct bacterial endotoxin testing
- Perform leachables testing
- Conduct pyrogen testing
- Test material stability in saline environment
Safety
- Identify primary safety endpoint
- Track surgical complications and adverse events
- Define acceptable risk levels
- Report unanticipated adverse effects within 10 days
- Monitor device hermeticity
Other considerations
- Sterilize implanted components to SAL 10-6
- Validate sterilization processes
- Test package integrity
- Consider MRI compatibility
- Evaluate electromagnetic interference
Relevant Guidances
- Spinal Plating Systems and Vertebral Body Replacement Devices - Content and Testing Requirements for 510k Submissions
- Design Controls for Medical Device Manufacturers
- Use of ISO 10993-1 for Biological Evaluation and Testing of Medical Devices
- Content of Premarket Submissions for Device Software Functions
- Applying Human Factors Engineering and Usability Engineering to Medical Devices
- Benefit-Risk Determinations for Medical Device Premarket Review
Related references and norms
- ISO 15004-1:2006: Ophthalmic instruments - Fundamental requirements and test methods
- IEC 60601-1-2:2001: Medical Electrical Equipment - Electromagnetic compatibility
- ISO 10993-7: Biological Evaluation of Medical Devices - Ethylene Oxide Sterilization Residuals
- ISO 17665-1:2006: Sterilization of health care products - Moist heat
- ISO 11135-1:2007: Sterilization of health care products - Ethylene oxide
- ISO 11607-1/2:2006: Packaging for terminally sterilized medical devices
- ASTM F1980-07: Standard Guide for Accelerated Aging of Sterile Barrier Systems
Original guidance
- Retinal Prostheses: Clinical, Non-Clinical, and Safety Recommendations for Electrical Stimulation Devices
- HTML / PDF
- Issue date: 2013-03-06
- Last changed date: 2020-02-28
- Status: FINAL
- Official FDA topics: Medical Devices, Ophthalmic, Investigational Device Exemption (IDE)
- ReguVirta summary file ID: e13dd67789cd29e513af7961e968e722
This post is licensed under CC BY 4.0 by the author.