(204 days)
The Pachycam is designed to photograph the eye and take Scheimpflug images of the anterior segment of the eye to evaluate the thickness of the cornea. The implanted keratometer measures the central radii of the cornea.
The Pachycam is a non-invasive, diagnostic system created to take photos of the anterior segment of the eye, portable and AC powered. The system is based on the Scheimpflug Principle for Slit Image photography. The device consists of a measurement unit, power supply and a CPU. The measuring system uses blue light (UV-free) given to a slit to illuminate the eye, and a CCD-Camera for photography. The device takes a series of the anterior segment of the eye from one fixed location (180°) and analyses one, selected by software.
The Pachycam Scheimpflug Camera is a non-invasive diagnostic system designed to photograph the eye and take Scheimpflug images of the anterior segment of the eye to evaluate the thickness of the cornea. It also measures the central radii of the cornea using an implanted keratometer.
1. Table of Acceptance Criteria and Reported Device Performance:
The provided document does not explicitly state quantitative acceptance criteria or specific performance metrics in a structured table. Instead, it focuses on demonstrating substantial equivalence to a predicate device (OCULUS Pentacam) and safety. The key aspects of "performance" are implicitly related to its ability to perform its intended functions accurately, consistently, and safely, as shown by internal company studies.
However, based on the device description and comparison to the predicate, we can infer some performance aspects:
| Feature/Metric | Acceptance Criteria (Inferred from Predicate Equivalence & Intended Use) | Reported Device Performance (Pachycam) |
|---|---|---|
| Accuracy of corneal thickness evaluation | Sufficiently accurate for clinical evaluation, comparable to predicate. | "The Pachycam is designed to photograph the eye and take Scheimpflug images of the anterior segment of the eye to evaluate the thickness of the cornea." "The Pachycam is proven effective for its intended uses through internal company studies." (Implies meeting the accuracy requirement for its stated purpose). |
| Accuracy of central radii measurement (keratometry) | Sufficiently accurate for clinical measurement, comparable to predicate. | "The implanted keratometer measures the central radii of the cornea." "The Pachycam is proven effective for its intended uses through internal company studies." (Implies meeting the accuracy requirement for its stated purpose). |
| Image Resolution | Clear enough for diagnostic interpretation (e.g., to evaluate corneal thickness). | 640 x 480 pixels (Compared to Pentacam's 800 x 600 pixels) - This difference is noted in the comparison table but is deemed acceptable for substantial equivalence, implying it still meets diagnostic utility. |
| Measurement Points per Image | Sufficient data points for accurate corneal analysis, comparable to predicate. | 600 per image (Compared to Pentacam's 500 per image) - This indicates an improvement in data density. |
| Safety (Eye, Electrical) | Must be eye-safe and meet electrical safety standards for medical devices. | "The light output is of an eye safe intensity and wavelength. The electrical safety requirements for medical devices are met." |
| Non-invasiveness | Device contact limited to chin and forehead, no direct eye contact during measurement. | "The Pachycam is a non-invasive diagnostic system, which contacts the patient only on his/her chin and forehead." |
Study Proving Acceptance Criteria:
The document explicitly states: "The Pachycam is proven effective for its intended uses through internal company studies."
This indicates that internal testing was conducted by OCULUS Optikgeräte GmbH to validate the device's performance against its intended uses, including the evaluation of corneal thickness and measurement of central corneal radii. While the specific details of these internal studies are not provided in the publicly available summary, the FDA's clearance (K041841) suggests they found sufficient evidence to support the claims of safety and effectiveness for substantial equivalence.
2. Sample Size Used for the Test Set and Data Provenance:
The document does not provide specific details on the sample size used for the test set or the data provenance (e.g., country of origin, retrospective/prospective) for the "internal company studies."
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications:
The document does not specify the number or qualifications of experts used to establish ground truth for the test set in the internal company studies.
4. Adjudication Method for the Test Set:
The document does not describe any adjudication method used for a test set. This detail is typically found in studies involving subjective interpretation of data, which may not be the primary evaluation method for a device like a Scheimpflug camera that provides quantitative measurements.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
A Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not explicitly mentioned or described in the provided document. The submission focuses on substantial equivalence to a predicate device based on technical and functional similarity, and internal effectiveness studies, rather than a direct comparison of human reader performance with and without AI assistance. The Pachycam primarily provides objective measurements.
6. Standalone (Algorithm Only) Performance Study:
Yes, the "internal company studies" that proved the device effective for its intended uses can be considered a form of standalone performance study. The Pachycam is described as generating images and measurements, implying the algorithm's ability to perform these functions independently to evaluate corneal thickness and measure central radii. The device's "effectiveness" through these studies would refer to the performance of its built-in measurement algorithms in producing accurate data.
7. Type of Ground Truth Used:
The document does not explicitly state the specific "type" of ground truth used for the internal company studies. However, for a device measuring corneal thickness and radii, the ground truth would typically involve:
- Reference Measurements: Comparison to established gold standard devices or methods (e.g., ultrasonic pachymetry, other validated keratometers, optical coherence tomography).
- Clinical Correlation: Evaluation of the device's measurements against clinical findings and established norms.
8. Sample Size for the Training Set:
The document does not provide any information regarding a training set sample size. This is understandable as the Pachycam is described as an optical imaging and measurement device based on a physical principle (Scheimpflug principle) and its effectiveness is likely validated through its measurement accuracy against known standards, rather than through a machine learning model that requires explicit training data.
9. How the Ground Truth for the Training Set Was Established:
As no training set is mentioned or implied for a machine learning model, specific information on how ground truth for a training set was established is not applicable/not provided in this document. The device's functionality relies on optical physics and algorithms inherent to the Scheimpflug principle for image acquisition and measurement, not on a machine learning model that is "trained."
§ 886.1850 AC-powered slitlamp biomicroscope.
(a)
Identification. An AC-powered slitlamp biomicroscope is an AC-powered device that is a microscope intended for use in eye examination that projects into a patient's eye through a control diaphragm a thin, intense beam of light.(b)
Classification. Class II (special controls). The device, when it is intended only for the visual examination of the anterior segment of the eye, is classified as Group 1 per FDA-recognized consensus standard ANSI Z80.36, does not provide any quantitative output, and is not intended for screening or automated diagnostic indications, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 886.9.