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The CA, an auxiliary lens adapter, when used in conjunction with RTVue, is indicated for in vivo imaging and measurement of the cornea and the other ocular structures of the anterior segment of the eve, including pachymetry and corneal power.

The already cleared (K071250) RTVue CA Module (CAM) is an instrument based on Fourier-Domain Optical Coherence Tomography (OCT) for in vivo imaging and measurement of the cornea and other ocular structures of the anterior segment of the eye with US FDA 510(k) clearance (K071250) in 2007. The RTVue CAM has been used in clinical practice for imaging the cornea, measuring corneal thickness, and visualizing the anterior segment angle. The RTVue CAM device uses the same Optical Coherence Tomography (OCT) technology that was previously cleared by FDA (K101505). The CAM adapter gives the user an option to use the RTVue device as previously approved for retina scans, or to use it for cornea and anterior eye scans. Aside from the CAM auxiliary attachment, the RTVue is virtually unchanged for the CAM use except the CAM software module provides for menu selections in the graphical user interface, which are selected by the operator to label corresponding corneal landmarks instead of those of the retina. The system scans a beam into patient's eye and uses a low coherence interferometer to measure the reflectivity of the ocular tissue. The cross-sectional ocular tissue structure is composed of sequence of A-scans. The RTVue has a traditional patient and instrumentinterface like most ophthalmic devices. The device is mounted on a motorized patient table. The patient will rest their head on the forehead and chin rest. The operator uses joystick to align the device to patient's eye. The computer has a graphic user interface for acquiring, and displaying the acquired image. The RTVue image acquisition speed and image resolution remain the same when used in conjunction with CAM.

The provided document describes the RTVue CAM with Corneal Power Measurement device and its performance data to support substantial equivalence. Here's a breakdown of the requested information:

1. Table of Acceptance Criteria and Reported Device Performance

2. Sample Size Used for the Test Set and Data Provenance

• Sample Size for Bench Test: Four ceramic balls of different known diameters were used. For each ball, 3 measurements (scans) were performed.
• Data Provenance: The data is from a "bench test" conducted by Optovue. The country of origin is not explicitly stated, but the manufacturer is based in Fremont, CA, USA. The data is retrospective in the context of the 510(k) submission, as it was collected prior to market approval.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

• This section describes a bench test using ceramic balls with known physical properties. Therefore, no human experts were involved in establishing the ground truth for this test set. The ground truth (true power and diameter of the ceramic balls) was determined by the physical characteristics of the manufactured ceramic balls.

4. Adjudication Method for the Test Set

• No adjudication method was used, as the test set consisted of inanimate ceramic balls with known ground truth values. The measurements were compared directly against these known values.

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

• No MRMC comparative effectiveness study involving human readers and AI assistance was conducted or mentioned in the provided document. The device is a measurement tool, not an AI diagnostic aid for human readers.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was Done

• Yes, a standalone performance test (bench test) of the RTVue CAM with Corneal Power Measurement was performed to verify its accuracy in measuring corneal power. This test involved the device measuring known ceramic balls.

7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)

• For the bench test, the ground truth was physical measurements/specifications of the ceramic balls (known diameter, from which a "truth value" for power was calculated using a specific refractive index).

8. The Sample Size for the Training Set

• The document does not provide information about a specific "training set" or its sample size. The device is a measurement instrument, and the upgrade is a software change for calculating corneal power from acquired images. It mentions a "calibration" process using a single ceramic ball with a prespecified radius of curvature. This calibration can be considered part of setting up the system, rather than a typical machine learning "training set."

9. How the Ground Truth for the Training Set was Established

• As noted above, no traditional "training set" for a machine learning algorithm is described. The "ground truth" for the device's calibration involves using a single ceramic ball with a known curvature (diameter 15.875mm, equivalent power 47.37D using index 1.376). This known physical property of the calibration sphere serves as the ground truth for the calibration process.

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