Tonometers for Measuring Intraocular Pressure - Testing and Performance Requirements
This guidance applies to manual and AC-powered tonometers intended to measure intraocular pressure (IOP) for glaucoma diagnosis. It covers contact tonometers (including Schiotz type, applanation type, and strain gauge) and non-contact (air-puff) tonometers, as well as devices that adjust IOP based on other ocular parameters.
Recommended Actions
- Conduct comprehensive bench testing for accuracy and repeatability
- Perform clinical testing if device is non-Goldmann-type
- Validate all cleaning and sterilization procedures
- Complete biocompatibility evaluation for patient-contacting materials
- Verify electrical safety and EMC compliance
- Prepare detailed device description including principles of operation
- Develop comprehensive labeling including all required elements
- Document software validation if applicable
- Conduct risk analysis and implement mitigations
- Prepare 510(k) submission including all test results and documentation
Key Considerations
Clinical testing
- Required for non-Goldmann-type tonometers only
- Comparison with calibrated Goldmann-type applanation tonometer
- Sample size of 150 eyes recommended
- Follow ANSI Z80.10-2003 protocol or equivalent
- Analysis should include scatter plots, Bland-Altman plots, and comparability assessment
Non-clinical testing
- Accuracy testing across nominal pressure range
- Repeatability testing with minimum 3 eyes per pressure value
- 10 measurements per eye
- Validation of any IOP adjustment features
Software
- Information based on “level of concern” as per FDA software guidance
Labeling
- Clear instructions for use
- Performance testing summary
- List of single use, disposable, and reusable parts
- Sterilization instructions if applicable
- Indications for use statement
- Scientific basis for IOP adjustment features
Biocompatibility
- Evaluation per ISO-10993 for limited contact with intact corneas
- List of patient-contacting materials
Safety
- Electrical safety per IEC 60601-1
- Electromagnetic compatibility per IEC 60601-1-2
- Sterility assurance level (SAL) of 1x10-6 for sterile devices
Other considerations
- Cleaning and sterilization validation for reusable devices
- High-level disinfection or sterilization for tip covers
Relevant Guidances
- Content of Premarket Submissions for Device Software Functions
- Use of ISO 10993-1 for Biological Evaluation and Testing of Medical Devices
- Reprocessing Instructions for Reusable Medical Devices and Non-Sterile Single-Use Devices - Development and Validation
- Electromagnetic Compatibility for Medical Devices and Accessories: Testing, Documentation, and Labeling Requirements
Related references and norms
- ANSI Z80.10-2003: Tonometers for measuring intraocular pressure
- ISO-10993: Biological Evaluation of Medical Devices Part 1
- IEC 60601-1: Medical Electrical Equipment Part 1: General Requirements for Safety
- IEC 60601-1-2: Electromagnetic Compatibility Requirements and Tests
Original guidance
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