(182 days)
The KOWA KT-800 is indicated for measuring intraocular pressure without contacting the eye to aid in the screening and diagnosis of glaucoma.
The KOWA KT-800 is a non-contact tonometer with an auto alignment ability of back and forth direction in addition to the same ability as the predicate device.
The KOWA KT-800 is a non-contact tonometer indicated for measuring intraocular pressure to aid in the screening and diagnosis of glaucoma. The study submitted to support its clearance was a substantial equivalence comparison to its predicate device, the Kowa Automated Tonometer KT-500.
Here's the breakdown of the acceptance criteria and the study:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for the KOWA KT-800 were implicitly defined by demonstrating equivalence to the predicate device, Kowa Automated Tonometer KT-500, across several technical and performance specifications. Since it's a substantial equivalence comparison, the "reported device performance" of the KOWA KT-800 is generally stated as being "same" or meeting the specified standards, implying it performs equivalently to the predicate.
| Acceptance Criteria (Based on Predicate) | Reported Device Performance (KOWA KT-800) |
|---|---|
| Measuring Function | |
| Measuring range: 0 to 60mmHg | Same |
| Measuring accuracy: +/-1mmHg for 0-30mmHg, +/-2mmHg for 30-60mmHg | Same |
| Measurement time: within 100 milliseconds | Same |
| Working distance: 11mm | Same |
| Automatic alignment function: Horizontal & vertical direction, manual alignment | 2D auto alignment (H&V), 3D auto alignment (H&V, F&B), Manual alignment |
| Automatic measurement function: Automatic air blow, manual air blow | Same |
| Moving range for measurement head (Up/Down): +/- 3mm | Up/Down: +/- 3mm |
| Moving range for measurement head (Right/Left): +/- 3mm | Right/Left: +/- 3mm |
| Fixation light: Internal green LED | Same |
| Electrical Safety IEC60601-1:1988, Amend 1:1991, Amend 2:1995 | Met all requirements |
| Electromagnetic Compatibility IEC60601-1-2:2001 | Met all requirements |
| Risk Management ISO14971:2000 | Met all requirements |
| Ophthalmic Instrument Requirements ISO15004:1997 | Met all requirements |
| Optical Hazard IEC60825-1:1993, Amend 1:1997, Amend 2:2001 | Class 1 |
| Tonometer Requirements ISO8612:2001 | Met all requirements |
2. Sample Size Used for the Test Set and Data Provenance
The provided document does not specify a patient-based test set or its sample size. The performance data primarily relies on bench testing and adherence to international standards rather than a clinical study with patient samples. Therefore, there is no information on data provenance (country of origin, retrospective/prospective).
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
Since no clinical test set with patient data was used to establish ground truth in the traditional sense, this information is not applicable. The "ground truth" for the device's performance was established through its compliance with recognized industry standards and direct comparison of technical specifications to a previously cleared predicate device.
4. Adjudication Method for the Test Set
As there was no clinical test set requiring expert interpretation or consensus, an adjudication method is not applicable.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
A MRMC comparative effectiveness study was not conducted, as the submission focused on substantial equivalence based on technical specifications and adherence to standards, not on human-in-the-loop performance improvement with AI assistance.
6. Standalone Performance Study (Algorithm Only Without Human-in-the-Loop Performance)
A standalone performance study, as typically understood in the context of an algorithm's diagnostic accuracy on images, was not performed. The assessment was of the device's functional and safety characteristics in a standalone capacity, specifically its ability to perform measurements and comply with safety standards, but not in terms of image interpretation or classification by an algorithm.
7. Type of Ground Truth Used
The "ground truth" for this device's performance was established through:
- Compliance with international standards for electrical safety (IEC60601-1), electromagnetic compatibility (IEC60601-1-2), risk management (ISO14971), ophthalmic instruments (ISO15004), optical hazard (IEC60825-1), and tonometers (ISO8612).
- Direct technical comparison to a legally marketed predicate device (Kowa Automated Tonometer KT-500), where the predicate device's established performance served as the benchmark.
8. Sample Size for the Training Set
Since this device is a hardware medical device with automated measurement functions and not an AI/ML-driven imaging or diagnostic algorithm, the concept of a "training set" for an algorithm does not apply. The device's internal mechanisms and algorithms would have been developed and refined during its engineering and manufacturing process, but this is not typically referred to as a "training set" in the context of an FDA submission for such a device.
9. How the Ground Truth for the Training Set Was Established
As there is no training set in the AI/ML context, this information is not applicable. The functional integrity and performance of the device's components and automated processes would be validated through engineering tests and quality control during design and manufacturing.
§ 886.1930 Tonometer and accessories.
(a)
Identification. A tonometer and accessories is a manual device intended to measure intraocular pressure by applying a known force on the globe of the eye and measuring the amount of indentation produced (Schiotz type) or to measure intraocular tension by applanation (applying a small flat disk to the cornea). Accessories for the device may include a tonometer calibrator or a tonograph recording system. The device is intended for use in the diagnosis of glaucoma.(b)
Classification. Class II.