(257 days)
The Bioptigen EnFocusTM device is intended to acquire, process, display and save depth-resolved images of ocular tissue microstructure using Spectral Domain Optical Coherence Tomography (SDOCT).
The EnFocusTM is indicated for use as an aid in the visualization of physiologic conditions of the eye through non-contact optical imaging. It is indicated for use on patient promotions from premature and neonant lintants to adult. The system is indicated for use in supine imaging, mounted to a superiod microscope, with coperative patients or patients under anesthesia.
The EnFocus™ is a non-contact, noninvasive ophthalmic imaging device that includes an OCT Engine, a scan head, a System Computer, an Uninterruptible Power Supply (UPS), a mobile Security Cart and the System Software. The EnFocus™ uses Spectral Domain Optical Coherence Tomography (SD-OCT) and a near infrared light source to image ocular tissue microstructures.
The EnFocus is coupled to a surgical micrsoscope for OCT imaging during ophthalmic surgical procedures. The EnFocus has been validated and found to be compatible for use with the Leica M844 Surgical Microscope and the Insight Instruments Super View™ Wide Angle Viewing System™ for retina visualization.
The software, InVivoVue™ Version 2.6, works with the hardware and the hardware controller to offer intuitive, flexible system control for high-speed volume data acquisition and imaging.
The EnFocus™ system includes two OCT-compatible objective lenses for use with the surgical microscope: a 175mm lens and 200mm lens. The system also offers a choice of accessory masks that may be deployed in the Leica M844 filter port to manage illumination glare artifacts when necessary.
Using the EnFocus™, OCT imaging may be acquired during the surgical procedure, without stopping a procedure or repositioning the surgical microscope. The surgical microscope position is stationary relative to the surgical procedure, and the surgical view is unaltered by the scanning of the OCT beam.
The Bioptigen EnFocus™ device aims to acquire, process, display, and save depth-resolved images of ocular tissue microstructure using Spectral Domain Optical Coherence Tomography (SDOCT). It's intended for visualizing physiological and pathological conditions of the eye through non-contact optical imaging, suitable for premature and neonatal infants to adults. The system is designed for supine imaging, mounted to a surgical microscope, with cooperative patients or patients under anesthesia.
Here's an analysis of the acceptance criteria and study data provided:
1. Acceptance Criteria and Reported Device Performance
The acceptance criteria for the EnFocus device are primarily based on demonstrating substantial equivalence to its predicate device, the Envisu™ SDOIS (Models C2200 and C2300), across three key areas:
- Visualization of ocular physiology of the anterior and posterior segments of the eye.
- Visualization of vascular blood flow in the retina with Doppler OCT.
- Measurement of ocular features using manual placement of on-screen calipers, with agreement within a specified margin.
The reported device performance is presented in comparison to the predicate device, specifically for the EnFocus 2300 and EnFocus 4400 models.
Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria Area | Specific Criterion | Reported Device Performance (EnFocus 2300) | Reported Device Performance (EnFocus 4400) | Met? |
|---|---|---|---|---|
| 1. Visualization of Ocular Physiology | Ability to visualize and identify specific physiologic features in volumetric images, showing high percentage agreement with the predicate. | - Inner limiting membrane: 81.7% agreement |
- Parafoveal nerve fiber layer: 100.0% agreement
- Inner nuclear layer: 100.0% agreement
- Outer plexiform layer: 100.0% agreement
- External limiting membrane: 100.0% agreement
- IS/OS Ellipsoids: 100.0% agreement
- End Tips Photoreceptor: 98.6% agreement
- Retina pigment epithelium: 100.0% agreement
- Choriocapillaris: 100.0% agreement
- Chorioscleral interface: 66.7% agreement
- Cornea epithelium: 100.0% agreement
- Bowman's layer: 94.3% agreement
- Cornea endothelium: 98.6% agreement
- Scleral corneal junction: 98.6% agreement
- Schlemm's canal: 60.0% agreement
- Iridocorneal angle: 81.7% agreement | - Inner limiting membrane: 80.6% agreement
- Parafoveal nerve fiber layer: 100.0% agreement
- Inner nuclear layer: 100.0% agreement
- Outer plexiform layer: 100.0% agreement
- External limiting membrane: 100.0% agreement
- IS/OS Ellipsoids: 100.0% agreement
- End Tips Photoreceptor: 94.4% agreement
- Retina pigment epithelium: 100.0% agreement
- Choriocapillaris: 100.0% agreement
- Chorioscleral interface: 62.5% agreement
- Cornea epithelium: 100.0% agreement
- Bowman's layer: 98.6% agreement
- Cornea endothelium: 98.6% agreement
- Scleral corneal junction: 97.2% agreement
- Schlemm's canal: 57.7% agreement
- Iridocorneal angle: 63.9% agreement | Generally Met (High agreement for most features).
Notably, Chorioscleral interface, Schlemm's canal, and Iridocorneal angle show lower agreement percentages, though specific thresholds for "acceptance" are not explicitly defined beyond "demonstrate substantial equivalence." The overall performance across numerous features implies general competence. |
| 2. Visualization of Vascular Blood Flow (Doppler OCT) | Ability to visualize and identify Doppler flow, showing high percentage agreement with the predicate. | - Doppler flow, superior: 93.1% agreement - Doppler flow, central: 88.9% agreement
- Doppler flow, inferior: 95.8% agreement | - Doppler flow, superior: 95.8% agreement
- Doppler flow, central: 88.9% agreement
- Doppler flow, inferior: 95.8% agreement | Met. All Doppler flow locations demonstrated high percentage agreement (88.9% - 95.8%). |
| 3. Caliper Measurements | Agreement of manual caliper measurements with the predicate device against a target equivalence margin of +/- 15 µm (0.015 mm) at the 95% confidence level. Also, linearity in agreement across the range of measurements (20 µm to 630 µm). | - 95% CI for mean difference for all 6 measured features (parafoveal peak inferior/superior, fovea, nerve fiber layer, cornea, cornea epithelium) within +/- 0.015 mm. - Pooled Graders (ENF23=f(Pred)): A=99.0%, B=-2.0 µm, R²=99.8% | - 95% CI for mean difference for all 6 measured features (parafoveal peak inferior/superior, fovea, nerve fiber layer, cornea, cornea epithelium) within +/- 0.015 mm.
- Pooled Graders (ENF44=f(Pred)): A=100.2%, B=1.4 µm, R²=99.8%
- Pooled Graders (ENF44=f(ENF23)): A=101.2%, B=3.5 µm, R²=99.8% | Met. All individual measurement 95% CIs were within the +/- 0.015 mm equivalence margin. High linearity (R²=99.8%) also indicates good agreement in measurements. |
2. Sample Size and Data Provenance
- Test Set Sample Size: 24 eyes of twelve adult subjects.
- Data Provenance: The study was conducted in an office setting. While a specific country of origin is not explicitly stated, the context of the FDA 510(k) submission strongly suggests the United States. The study was prospective in nature, as images were "collected" and "evaluated."
3. Number and Qualifications of Experts for Ground Truth
- Number of Experts: Three ophthalmic graders.
- Qualifications: "Ophthalmic graders" are mentioned. No specific experience level (e.g., "radiologist with 10 years of experience") or board certification is provided in the document.
4. Adjudication Method for the Test Set
The document states that the three ophthalmic graders "independently reviewed the images and documented evaluations." For the "Ocular Physiology and Presence of Doppler Flow," they "identified the presence or absence of physiologic features in a binary test of agreement." This method implies a comparison of each grader's evaluation against the predicate, and then likely an agreement statistic was calculated among the graders relative to the predicate's findings. However, a specific adjudication method like "2+1" or "3+1" to establish a consensus ground truth from the graders themselves is not explicitly stated. The "Percent Agreement with Predicate" suggests each grader's individual agreement with the predicate's established findings.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No explicit MRMC comparative effectiveness study that assesses how much human readers improve with AI vs. without AI assistance was done. The study evaluated the device's performance (EnFocus 2300 and EnFocus 4400) in terms of agreement with a predicate device, not in comparison to human readers or an AI-assisted workflow. Although human graders were involved in the evaluation of the images from the new devices, their role was to evaluate the images in comparison to the predicate, not to measure an improvement in their own performance with AI assistance.
6. Standalone (Algorithm Only) Performance
Based on the provided text, the EnFocus device itself is the system under evaluation, which includes its image acquisition, processing, display, and saving capabilities. The performance metrics (e.g., visualization agreement and measurement accuracy) evaluate the device's output rather than a separate algorithm's performance in isolation. The study design does not present a standalone algorithm's performance independent of the full device system. The "Key Performance Attributes" section also mentions "Optical performance testing" conducted in accordance with established requirements, suggesting standalone technical performance, but the clinical data focuses on device output.
7. Type of Ground Truth Used
The ground truth for comparison was the predicate device, Envisu 2300. The study measures "Percent Agreement with Predicate" for visualization tasks and "Mean Difference (Predicate - New Device)" for caliper measurements. This indicates that the evaluations from the EnFocus devices were compared against what was already established or visible in images from the predicate device.
8. Sample Size for the Training Set
The document does not provide any information regarding a training set sample size. This is a 510(k) submission for a medical device which is largely based on substantial equivalence to a predicate, rather than an AI/ML device that typically requires extensive training data. The "Software Verification and Validation Testing" indicates compliance with guidance for "Software Contained in Medical Devices" but does not detail machine learning model development.
9. How Ground Truth for the Training Set Was Established
Since no information regarding a training set is provided, there is no mention of how ground truth for a training set was established. The clinical study described served as a validation/test set to demonstrate equivalence to the predicate device.
§ 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.