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The Keeler TonoCare Tonometer is a hand-held, battery operated, non-contact tonometer intended to be used for measuring intraocular pressure (IOP) of the human eye with less than 3D in corneal astigmatism.

The Keeler TonoCare Tonometer is designed to measure Intra Ocular Pressure (IOP) to aid in the screening and diagnosis of glaucoma without contacting the eye. The Keeler TonoCare Tonometer has been designed using the same ergonomics as the predicate device described in 510(k) submission K093298. Both products consist of an air generation system in the form of a vacuum Diaphragm pump, an air reservoir, a solenoid valve, a light source and an opto-electronic platform which is used for position detection and IOP measurement. The basic concept of operation is the same. The user positions the instrument close to the patient's cornea using a targeting system. As the user moves the instrument closer to the patient, the reflection off the cornea from the built-in light source increases until the predefined firing thresholds on the built-in photodiodes have been met. Once this condition has been met, a quantized puff of air is automatically projected toward the patient's cornea. As the cornea flattens due to the force of the puff of air, the light being reflected off of the cornea changes shape which in turn changes the profile of the light being reflected back onto the photodiodes. The rate of change of this reflection is monitored by the photodiodes and converted into intraocular pressure in units of mmHg by the on-board microprocessor.

The document provided describes performance testing for the Keeler TonoCare Tonometer, primarily focusing on its equivalence to a predicate device and a reference standard tonometer. However, it does not detail acceptance criteria or a study that proves a device meets those acceptance criteria in the context of an AI/algorithm's performance. The document is for a physical medical device (a tonometer for measuring intraocular pressure), not an AI or algorithm.

Therefore, many of the requested points, such as "effect size of how much human readers improve with AI vs without AI assistance," "standalone (i.e. algorithm only without human-in-the-loop performance) was done," or "sample size for the training set," are not applicable to this document as it does not describe an AI medical device.

I will interpret the request as asking for the acceptance criteria and the study that proves the Keeler TonoCare Tonometer (a physical device) meets its performance requirements, based on the provided text.

Here's a breakdown based on the provided text, adapted to the context of a physical medical device:

Device: Keeler TonoCare Tonometer
Intended Use: Measuring intraocular pressure (IOP) of the human eye with less than 3D in corneal astigmatism.

1. A table of acceptance criteria and the reported device performance:

The acceptance criterion is derived from ISO 8612 (comparable to ANSI Z80.10) for comparison with a reference tonometer.

*   **Data Provenance:** The study was a "single visit, single-center" study. While the document mentions "Keeler Ltd, Clewer Hill Road, Windsor, Berkshire, United Kingdom" as the manufacturing location, the specific country of origin for the clinical data is not explicitly stated, but implies a UK or European context given the European market launch mentioned. It was a **prospective** study ("Subjects were recruited according to the following inclusion and exclusion criteria").

• Repeatability/Reproducibility Bench Test:
  • Sample Size:
    • Repeatability: Approximately 50 individual readings for each of 5 pressure values on a manometrically controlled test eye.
    • Reproducibility: Measurements from three different TonoCare units by two different operators across 5 pressure values.
  • Data Provenance: Bench testing. Location not specified, but likely at the manufacturing facility.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

• Number of Experts: Two experienced observers.
• Qualifications of Experts: Described as "experienced observers." No further detail (e.g., specific clinical specialty, years of experience) is provided.

4. Adjudication method for the test set:

• The study design was a "paired crossover study" comparing the TonoCare NCT to the Perkins Applanation Tonometer (AT). The "ground truth" for IOP measurements in this context was established by the reference standard Perkins AT (which itself is described as using the same basic principle as the Goldmann AT, a recognized reference).
• There's no mention of an adjudication process between the "two experienced observers" for the clinical measurements. It's implied that both observers took measurements using both devices.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:

• N/A. This was a study for a physical tonometer device, not an AI or algorithm. Therefore, no MRMC study comparing human readers with and without AI assistance was performed or is relevant to this submission.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:

• N/A. This was a physical device, not an algorithm. The device measures IOP. Human operators are required to use the device.

7. The type of ground truth used:

• Clinical Performance Study: The ground truth for IOP measurement was established by comparison to a reference standard clinical device, specifically the Perkins Applanation Tonometer (AT), which is considered an "established, gold standard" comparable to the Goldmann Tonometer.
• Repeatability/Reproducibility Study: The ground truth was a manometrically controlled test eye with known pressure values.

8. The sample size for the training set:

• N/A. This refers to a physical device, not an AI/ML algorithm that requires a training set. The device was likely designed and calibrated, not "trained" in the typical ML sense.

9. How the ground truth for the training set was established:

• N/A. As above, no training set in the AI/ML sense.
• However, the document mentions:
  • "The TonoCare Tonometer unit was initially cross calibrated on several rubber eyes against Keeler Pulsair IntelliPuff (K093298)."
  • "In addition, a mini trial on volunteers have been conducted to further refine the calibration of the TonoCare Tonometer in order to minimize the error between the devices."
  • The "ground truth" for calibration appears to be mechanical phantom eyes and real-world "mini trial" data compared against a known predicate device (Keeler Pulsair IntelliPuff) and the reference Perkins/Goldmann AT.

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