(155 days)
The CIRRUS™ HD-OCT is a non-contact, high resolution tomographic and biomicroscopic imaging device. It is indicated for in-vivo viewing, axial cross-sectional, and three-dimensional imaging and measurement of anterior and posterior ocular structures, including cornea, retinal nerve fiber layer, ganglion cell plus inner plexiform layer, macula, and optic nerve head.
The CIRRUS™ HD-OCT Reference Database is a quantitative tool used for the comparison of retinal nerve fiber layer thickness, macular thickness, ganglion cell plus inner plexiform layer thickness, and optic nerve head measurements to a database of healthy subjects.
CIRRUS™ HD-OCT AngioPlex angiography is indicated as an aid in the visualization of vascular structures of the retina and choroid.
The CIRRUS™ HD-OCT is indicated for use as a diagnostic device to aid in the detection and management of ocular diseases including, but not limited to, macular holes, cystoid macular edema, diabetic retinopathy, age-related macular degeneration, and glaucoma.
The subject device is a computerized instrument that acquires and analyses cross-sectional tomograms of anterior ocular structures (including comea, retinal nerve fiber layer, macula, and optic disc). It employs non-invasive, non-contact, low-coherence interferometry to obtain these high-resolution images. CIRRUS 6000 has a 100kHz scan rate for all structural and angiography scans.
The subject device uses the same optical system, and principle of operation as the previously cleared CIRRUS 6000 (K222200) except for the reference database functionality.
The subject device contains a newly acquired reference database which was collected on K222200. This study data compares macular thickness, ganglion cell thickness, optic disc and RNFL measurements to a reference range of healthy eyes as guided by the age of the patient and /or optic disc size. Reference database outputs are available on Macular Cube 200x200, and Optic Disc Cube 200x20 scan patterns. All other technical specifications have remained the same as the predicate K222200.
Here's a breakdown of the acceptance criteria and the study proving the device meets them, based on the provided text:
Acceptance Criteria and Reported Device Performance
The acceptance criteria are implicitly met by the successful development of the CIRRUS™ HD-OCT Reference Database (RDB) and its ability to provide normative data for comparison. The study aims to establish these reference limits.
| Acceptance Criteria Category | Specific Criteria (Inferred from study purpose) | Reported Device Performance (Summary of RDB Establishment) |
|---|---|---|
| Reference Database Functionality | Device can generate a normative reference database for key ocular parameters (Macular Thickness, Ganglion Cell Thickness, ONH parameters, RNFL thickness). | CIRRUS™ 6000 RDB for macular thickness and optic nerve head scan values was developed. Reference limits were established for Macular Thickness, Ganglion Cell Thickness, Optic Nerve Head parameters, and Retinal Nerve Fiber Layer thickness values. |
| Statistical Validity of RDB | Reference limits are calculated using appropriate statistical methods (regression analysis) and incorporate relevant covariates (age, optic disc size). | Reference range limits were calculated by regression analysis for the 1st, 95th, and 99th percentiles. Age was used as a covariate for Macular Thickness and Ganglion Cell Thickness. Age and Optic Disc Size were used as covariates for ONH parameters and RNFL thickness. |
| Clinical Applicability of RDB | The RDB allows for effective comparison of a patient's measurements to that of healthy subjects, aiding in the assessment and management of ocular diseases. | The RDB was created to help clinicians assess and effectively compare a patient's measurements to that of healthy subjects, representative of the general population. The device provides color-coded indicators based on RDB limits. |
| Image Quality / Scan Acceptability | Only high-quality scans are included in the reference database. | Only the scans that met the pre-determined image quality criteria were included in analysis. |
| Safety | No adverse events or device effects during RDB development. | There were no adverse events or adverse device effects recorded during the study. |
Study Details
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Sample Size and Data Provenance:
- Test Set (for RDB establishment): 870 subjects had one eye included in the analysis from an initial enrollment of 1000 subjects.
- Data Provenance: Prospective, multi-site study conducted at eight (8) clinical sites across the USA.
- Test Set (for RDB establishment): 870 subjects had one eye included in the analysis from an initial enrollment of 1000 subjects.
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Number of Experts and Qualifications for Ground Truth:
- The document does not specify the number or qualifications of experts used to establish the ground truth for the test set regarding the "healthiness" of the subjects. The eligibility and exclusion criteria (e.g., "presence of any clinicant vitreal, retinal optic nerve, or choroidal disease in the study eye, including glaucoma or suspected glaucoma. This was assessed based on clinical examination and fundus photography.") imply that ophthalmologists or optometrists would have made these clinical judgments, but the specific number or their experience level is not detailed.
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Adjudication Method for the Test Set:
- The document does not explicitly describe an adjudication method for determining the "healthy" status of the subjects. It states that inclusion/exclusion was "assessed based on clinical examination and fundus photography" by unnamed personnel at the clinical sites. There is no mention of a consensus process, independent review, or other adjudication for the ground truth.
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Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- No MRMC comparative effectiveness study was done to assess how human readers improve with AI vs. without AI assistance. The study focuses solely on establishing the normative reference database for the device's measurements. The RDB itself is a tool to be used by clinicians, but its impact on clinical decision-making or reader performance was not evaluated in this submission.
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Standalone Performance:
- This is a standalone performance study in the sense that the device, equipped with the new reference database, generates the normative values and compares patient data to them. It's the performance of the device's RDB calculation and display, not an AI algorithm performing diagnostic tasks without human input.
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Type of Ground Truth Used:
- Clinical Ground Truth: The ground truth for defining "healthy subjects" was based on extensive clinical examination, fundus photography, and adherence to strict inclusion/exclusion criteria (e.g., no known ocular disease, specific visual acuity, IOP, refraction limits). This represents a clinically defined healthy population.
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Sample Size for the Training Set:
- The term "training set" is not explicitly used in the context of a machine learning model, as the primary objective was to establish a statistical reference database. The entire dataset of 870 subjects (with qualified scans) was used to develop the reference database. So, the sample size for developing the reference database was 870 subjects.
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How Ground Truth for the Training Set Was Established:
- The "ground truth" for the subjects included in the reference database was established by defining them as "healthy subjects" through rigorous inclusion and exclusion criteria applied at 8 clinical sites across the USA. These criteria included:
- Age 18 years and older
- Best corrected visual acuity (BCVA) of 20/40 or better in either eye
- IOP
- The "ground truth" for the subjects included in the reference database was established by defining them as "healthy subjects" through rigorous inclusion and exclusion criteria applied at 8 clinical sites across the USA. These criteria included:
§ 886.1570 Ophthalmoscope.
(a)
Identification. An ophthalmoscope is an AC-powered or battery-powered device containing illumination and viewing optics intended to examine the media (cornea, aqueous, lens, and vitreous) and the retina of the eye.(b)
Classification. Class II (special controls). The device, when it is an AC-powered opthalmoscope, a battery-powered opthalmoscope, or a hand-held ophthalmoscope replacement battery, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 886.9.