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Measuring the refraction of the eye giving both lower and higher order aberrations
Measurement of the shape of the cornea
Retro-illumination imaging of the eye
Measuring the intraocular pressure without contacting the eye for glaucoma evaluation.
Photographing the eye and taking images of the eye to evaluate the thickness of the central cornea.
Full corneal thickness map.
Scheimpflug imaging.
Anterior chamber imaging.
Pupil image.
Image of the cornea relative to the iris.

The VX130 is a multifunctional ophthalmic diagnostic device.
The VX130 combined wavefront aberrometer, corneal topographer, cataract screening device, Scheimpflug pachymeter, and non-contact tonometer is a single platform that contains five different measurement units.
The wavefront aberrometer works on the Shack-Hartmann principle and is used as an advanced autorefractometer that measures both lower and higher order aberrations of the eye. Retro illumination is used to image ocular opacities. The corneal topographer uses a Placido disk to measure keratometry and the detailed shape of the cornea. A linear scanning Scheimpflug pachymeter measures the thickness of the cornea by illuminating it with a slit of light and photographing it using the Scheimpflug technique. Anterior and posterior corneal shape are also measured from the Scheimpflug images. An air puff non-contact tonometer is included for measurement of the intraocular pressure. The device is fully automated and a number of different measurements can be performed by a single command including alignment and focusing.

Here's an analysis of the acceptance criteria and study proving the device meets them, based on the provided text:

Device: VX130 Ophthalmic Diagnostic Device
Primary Function under review (for the comparison study): Pachymetry (corneal thickness measurement)

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't explicitly state formal "acceptance criteria" in terms of specific thresholds for performance metrics. Instead, the approach is one of demonstrating substantial equivalence to a predicate device (Galilei G4). The implicitly accepted performance is that the VX130's measurements are not significantly different from those of the predicate device, across various anterior segment parameters, and that it demonstrates sufficient repeatability.

Interpretation of Performance: The average differences between the VX130 and Galilei G4 are quite small (e.g., -0.43 µm for CCT), and the 95% confidence intervals (not explicitly provided for CCT, but -15.03 to 14.16 µm for CCT suggests the differences are within a clinically acceptable range for equivalence, especially considering the standard deviations). The repeatability standard deviations for the VX130 are also small, indicating consistent measurements.

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

• Comparison Study (VX130 vs. Galilei G4):

  • Sample Size: Not explicitly stated, however, Table 2 (Repeatability of VX130) mentions "42 eyes were measured 3 times each". It is highly probable that the comparison study (Table 1) also used these 42 eyes, or a similar sample size, as it's part of the same "Tests for pachymetry" section. Assuming 42 subjects, likely n = 42 eyes.
  • Data Provenance: Not specified; retrospective or prospective is not mentioned. Country of origin not mentioned.

• Repeatability Study (Table 2 - Std dev 1):

  • Sample Size: "a single eye was measured ten times".

• Repeatability Study (Table 2 - Std dev 2):

  • Sample Size: "42 eyes were measured 3 times each".

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

The document does not mention the use of experts to establish ground truth for the test set. The study design is a comparison between two devices (VX130 and Galilei G4) and a repeatability assessment of the VX130 itself. The Galilei G4's measurements serve as the reference for comparison, not an expert-derived ground truth.

4. Adjudication Method for the Test Set

No adjudication method is mentioned as there were no human readers/interpreters involved in establishing the ground truth for the measurement comparison. The comparison is between automated device measurements.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No MRMC study was done. This study focuses on device performance for automated measurements, not on human reader performance with or without AI assistance.

6. Standalone Performance Study

Yes, a standalone performance study was done for the pachymetry function of the VX130 in two ways:

• Comparison to a predicate device: This evaluates the VX130's agreement with an established device (Galilei G4). The results are presented in Table 1, showing "small differences between the devices."
• Repeatability study: This demonstrates the consistency of the VX130's own measurements. The results are presented in Table 2, showing low standard deviations for repeated measurements.

7. Type of Ground Truth Used

The ground truth for the comparison study was the measurements obtained from a legally marketed predicate device (Galilei G4). This is a common approach for demonstrating substantial equivalence for quantitative diagnostic devices. For the repeatability study, the "ground truth" is inferred from the consistency of the device's own measurements over multiple trials.

8. Sample Size for the Training Set

The document does not mention a training set. This is not an AI/Machine Learning device that requires a training set in the conventional sense. The device's functionality is based on established optical and measurement principles (Shack-Hartmann, Placido disk, Scheimpflug), and its performance is evaluated against a predicate device and through repeatability.

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

Not applicable, as there is no mention of a training set for an AI/ML algorithm.

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