(86 days)
The CONTAFLEX 55 (methafilcon A) Spherical Soft Contact Lenses for daily wear are indicated for the correction of visual acuity in aphakic and not aphakic persons with non-diseased eyes with myopia or hyperopia. The lens may be worn by persons who exhibit refractive astigmatism of .75 diopters or less where the astigmatism does not interfere with visual acuity. The lens may be disinfected using a chemical disinfecting system.
Eyecare practitioners may prescribe the lenses for frequent/planned replacement wear, with cleaning, disinfection and scheduled replacement. When prescribed for frequent/planned replacement wear, the lens may be cleaned and disinfected using a chemical (not heat) lens care system.
The CONTAFLEX 55 Spherical Soft Contact Lenses are fabricated from methafilcon A, which in the dry (unhydrated) state may be machined and polished. The hydrophilic nature of this material allows the lens to become soft and pliable when immersed in an aqueous solution.
The ionic lens material. (methafilcon A) is a co-polymer of 2-Hydroxyethylmethacrylate (2-HEMA) and Methacrylic Acid, cross-linked with ethylene glycol dimethacrylate (EGDMA), plus an initiator. The co-polymer consists of 45% methafilcon A and 55% water by weight when immersed in normal buffered saline solution. The lens is available in clear and with a blue visibility-handling tint, [phthalocyaninato (2-)] copper. The methafilcon A name has been adopted by the United States Adopted Names Council (USAN).
In the hydrated state, the lens conforms to the curvature of the eye covering the cornea and extending slightly beyond the limbus forming a colorless, transparent optical surface. The (methafilcon A) soft hydrophilic contact lens has a spherical back surface. The hydrophilic properties of the lens require that it be maintained in a fully hydrated state in a solution compatible with the eye. If the lens dries out, it will become hard and appear somewhat warped however, it will return to its proper configuration when completely rehydrated in the proper storage solution.
The hydrophilic characteristics allow aqueous solutions to enter the lens and in its fully hydrated state the lens is approximately 55% water by weight. The physical properties of the lens are:
Refractive Index 1.405 (hydrated)
Light Transmission (clear) greater than 94%
Light Transmission (tinted) greater than 94%
Water Content 55 % ± 2%
Specific Gravity 1.067
Oxygen Permeability 19.6 X 10-11 (cm²/sec) (ml O₂/ml x mm Hg @ 35°C), (revised Fatt method).
The provided text describes the CONTAFLEX 55 (methafilcon A) Spherical Soft Contact Lens and its substantial equivalence to a predicate device. However, the document does not describe a study involving acceptance criteria in the typical sense of a clinical trial or algorithm performance study.
Instead, the submission for CONTAFLEX 55 focuses on establishing substantial equivalence to an already marketed device ("BENZ methafilcon A"). This is a regulatory pathway where the new device is compared to a legally marketed predicate device to demonstrate it is as safe and effective. The "acceptance criteria" here are essentially the demonstration that the new device shares fundamental technological characteristics and intended use with the predicate device, and does not raise new questions of safety or effectiveness.
Here's an analysis based on your requested information, acknowledging the nature of this 510(k) submission:
Acceptance Criteria and Device Performance (based on Substantial Equivalence)
Since this is a substantial equivalence submission, the "acceptance criteria" are implied by the comparison to the predicate device. The performance is demonstrated by showing similar characteristics.
| Acceptance Criteria (Implied by Predicate) | Reported Device Performance (CONTAFLEX 55) |
|---|---|
| Intended Use: Correct visual acuity in aphakic/non-aphakic persons with non-diseased eyes (myopia/hyperopia), astigmatism ≤ 0.75 D. | Indicated for daily wear for the correction of visual acuity in aphakic and not aphakic persons with non-diseased eyes with myopia or hyperopia. The lens may be worn by persons who exhibit refractive astigmatism of .75 diopters or less where the astigmatism does not interfere with visual acuity. |
| Functionality: Act as a refractive medium. | After machining from the optical blank, the contact lenses act as a refractive medium that focus light rays from near and distant objects on the retina. |
| Indications: Daily wear, Soft (hydrophilic) contact lens. | Daily wear, Soft (hydrophilic) contact lens. |
| Production Method: Lathe-cut. | Lathe-cut. |
| FDA Group #: Group # 4 (>50% Water, ionic Polymers). | Group # 4 (>50% Water, ionic Polymers). |
| USAN name: methafilcon A. | methafilcon A. |
| Water Content: 55.0%. | 55.0% ± 2% (reported in device description, 55.0% in table). |
| Oxygen Permeability: Comparable to 18.3 X 10-11 (cm²/sec). | 19.6 X 10-11 (cm²/sec) (ml O₂/ml x mm Hg @ 35°C), (revised Fatt method). |
| Specific Gravity: Comparable to 1.128. | 1.067. |
| Toxicology: Non-cytotoxic, non-systemically toxic, non-ocularly irritating. | Meets requirements of Agarose Overlay Method (cytotoxicity). Considered non-toxic (systemic). Produced no ocular irritation. |
| Shelf Life: Satisfied. | Satisfied via referencing rights granted to Contamac Ltd. for 510(k) 973597. |
The "study" that proves the device meets these "acceptance criteria" is the pre-clinical equivalency and safety testing performed to demonstrate its characteristics align with the predicate device.
Detailed Study Information:
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Sample size used for the test set and the data provenance:
- The document describes pre-clinical testing (in-vitro cytotoxicity, systemic toxicity, acute ocular irritation) rather than a clinical "test set" with human subjects for performance evaluation like an AI device would have. Specific sample sizes for these preclinical tests are not provided in the summary.
- Data provenance: Not explicitly stated, but these are laboratory-based preclinical tests conducted on the device material itself, likely in a controlled lab environment.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience):
- This question is not applicable to this type of submission. There was no "ground truth" to establish in the context of expert review of images or clinical outcomes. The "ground truth" for the preclinical tests would be the established scientific methods and standards (e.g., ISO 10993-5 for cytotoxicity).
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Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not applicable. This submission does not involve adjudication of expert opinions or discrepancies in a clinical test set.
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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. This is not an AI device. This section is entirely not applicable.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- No. This is not an AI device. This section is entirely not applicable.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc):
- For the preclinical tests, the "ground truth" refers to the established scientific and regulatory standards for material safety (e.g., ISO 10993-5 for cytotoxicity, and generally accepted methods for systemic toxicity and ocular irritation). For material properties (water content, oxygen permeability), the ground truth is derived from standardized laboratory measurement methods (e.g., revised Fatt method for oxygen permeability).
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The sample size for the training set:
- Not applicable. This contact lens is not an AI/ML device that requires a training set.
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How the ground truth for the training set was established:
- Not applicable. This contact lens is not an AI/ML device that requires a training set.
§ 886.5925 Soft (hydrophilic) contact lens.
(a)
Identification. A soft (hydrophilic) contact lens is a device intended to be worn directly against the cornea and adjacent limbal and scleral areas of the eye to correct vision conditions or act as a therapeutic bandage. The device is made of various polymer materials the main polymer molecules of which absorb or attract a certain volume (percentage) of water.(b)
Classification. (1) Class II if the device is intended for daily wear only.(2) Class III if the device is intended for extended wear.
(c)
Date PMA or notice of completion of a PDP is required. As of May 28, 1976, an approval under section 515 of the act is required before a device described in paragraph (b)(2) of this section may be commercially distributed. See § 886.3.