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.
What You Need to Know? 👇
What are the key requirements for 510(k) submissions for tonometers?
Tonometer 510(k) submissions must include device description, risk analysis, bench testing for accuracy and repeatability, clinical performance data (for non-Goldmann types), biocompatibility evaluation, electrical safety testing, and validation of cleaning/sterilization methods per FDA guidance.
How should accuracy testing be conducted for tonometers in 510(k) submissions?
Accuracy testing should use pressure-controlled eyes (model, animal, or eye bank) at the lower limit and every 10 mmHg increment up to the upper limit of the measurement range, with proper validation of baseline IOP throughout testing.
What clinical performance requirements apply to non-Goldmann-type tonometers?
Non-Goldmann-type tonometers require comparison with calibrated Goldmann-type applanation tonometers using 150 eyes following ANSI Z80.10-2003 protocol, with scatter plots, Bland-Altman analysis, and demonstrating ≤5% paired differences exceeding tolerance limits.
What biocompatibility testing is required for tonometer patient-contacting materials?
Patient-contacting materials must be evaluated per ISO-10993 for limited contact with intact corneas. If identical materials and processing are used in a predicate device with same contact type/duration, the predicate device may be referenced instead.
How should cleaning and sterilization validation be addressed for reusable tonometers?
Reusable tonometers require validated cleaning, disinfection, and sterilization methods described in the submission. Labeling must include user instructions based on validation processes, achieving sterility assurance level (SAL) of 1 x 10⁻⁶ when applicable.
What electrical safety standards must tonometers comply with for FDA clearance?
Tonometers must comply with IEC 60601-1 for general electrical safety requirements and IEC 60601-1-2 for electromagnetic compatibility requirements and testing, or demonstrate compliance with equivalent methods to ensure device safety and performance.
What You Need to Do 👇
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