(14 days)
The Horizon 55 Westint and Horizon 55 (methafilcon A) Soft (hydrophilic) Contact Lenses for daily wear are indicated for the correction of visual acuity in non aphakic persons with non-diseased eyes with myopia or hyperopia.
W-55 (methafilcon A) clear or tinted lens blanks are a hydrophilic polymer of 2hydroxyethy methacrylate crossed linked with ethyleneglycol dimethacrylate. The lens consists of 45% methafilcon and 55% water by weight when immersed in buffered saline solution. When the lens blank is tinted blue, up to .8 % of the color additive Copper Phthalocyanine Blue Pigment will be added to the MA. The color additive conforms to 21 CFR Part 74.3045.
The soft contact lenses that are manufactured from W-55 lens blanks, clear or tinted, can be lathe cut into a hemispherical shell which are designed to fit over the corneal surface of the eye. These lenses are designed with varying base curves which conform to the shape of the radius of the cornea and center over the apex of the cornea to provide corrective myopia (nearsightedness), hyperopia (farsightedness), and astigmatism (multifocal). Each lens provides corrective power, which corresponds to the refractive power of the eye to which it is being treated.
Each lens is designed with a base curve on the internal side of the lens and an optical zone in the center of the lens, generally of a diameter greater than 6 mm. The Secondary and tertiary curves as well as beveled edge configurations are built into the lens for the purpose of aiding on the lens centration and comfort.
This document describes a 510(k) submission for a modification to an approved device, specifically adding a visibility tint to contact lens blanks and the resulting contact lenses. It is not an AI/ML device, so it doesn't contain information typically found in studies for AI/ML devices, such as sample sizes for test/training sets, expert ground truth, or MRMC studies. The "study" here refers to the testing conducted to ensure the safety and effectiveness of the tinted lenses compared to the already approved clear lenses.
Here's an analysis based on the provided text, focusing on the established safety and effectiveness of the modified device:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (from predicate device K954524) | Reported Device Performance (for tinted lenses) | Study/Section |
|---|---|---|
| Safety: | ||
| No identifiable evidence of tint pigment leaching | No identifiable evidence of tint pigment leaching | 6.0 Summary of Safety and Effectiveness |
| No cellular or systemic toxicity | No evidence of cellular or systemic toxicity | 7.1 Toxicology |
| No ocular irritation | No evidence of ocular irritation | 7.1 Toxicology |
| Biocompatibility (cytotoxicity, systemic toxicity, ocular irritation) | Passed (No evidence) | 7.1 Toxicology |
| Effectiveness/Performance: | ||
| Light transmittance within limits | Equivalent to 510(k) K954524 (clear lenses) | 7.2 Physical/Optical Characteristics |
| Refractive index within limits | Equivalent to 510(k) K954524 (clear lenses) | 7.2 Physical/Optical Characteristics |
| Water content within limits | Equivalent to 510(k) K954524 (clear lenses) | 7.2 Physical/Optical Characteristics |
| Linear expansion within limits | Equivalent to 510(k) K954524 (clear lenses) | 7.2 Physical/Optical Characteristics |
| Radial expansion within limits | Equivalent to 510(k) K954524 (clear lenses) | 7.2 Physical/Optical Characteristics |
| Tensile strength within limits | Equivalent to 510(k) K954524 (clear lenses) | 7.2 Physical/Optical Characteristics |
| Manufacturing process validated | No changes to validated process in 510(k) K954524 | 7.3 Microbiology |
| Compatibility (e.g., lens durability over wear cycles) | Within normal limits after 30 cycles | 7.4 Compatibility |
| Shelf life (with 10-year expiration) | Shelf life studies started for tinted lenses, will be completed later. No change to 10-year expiration for button. | 7.5 Shelf Life |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: The document does not specify a numerical sample size for the "test set" in terms of how many tinted lenses were tested for each characteristic. It refers to "samples of tinted lenses" (e.g., in Toxicology and Physical/Optical Characteristics sections). For compatibility, it states "all lenses were within normal limits" after 30 cycles, implying a sample was used but no number is given.
- Data Provenance: The studies were conducted by Westcon Contact Lens Company, Inc. (the submitter). The country of origin is not explicitly stated but implies internal studies based in the US (Grand Junction, CO). The studies are retrospective in the sense that they are comparing the newly tinted lenses against previously established data for the clear lenses (predicate device K954524), and are prospective in that new testing was performed on the tinted lenses.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
- This is not applicable as the device is a medical device (contact lens) and not an AI/ML algorithm that requires expert annotation for ground truth. The "ground truth" here is objective physical and chemical measurements (e.g., light transmittance, toxicity tests).
4. Adjudication Method for the Test Set
- Not applicable as this is not an AI/ML device. The "adjudication" is based on laboratory test results meeting established scientific and regulatory standards.
5. 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
- Not applicable. This is a contact lens, not an AI/ML system that would assist human readers.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not applicable. This is a physical medical device, not an algorithm.
7. The Type of Ground Truth Used
- The "ground truth" for demonstrating safety and effectiveness relies on objective scientific, chemical, and physical measurements and toxicological assessments. This includes:
- Chemical analysis for pigment leaching.
- Biological assays for cytotoxicity, systemic toxicity, and ocular irritation.
- Physical measurements for light transmittance, refractive index, water content, linear expansion, radial expansion, and tensile strength.
- Compatibility testing (e.g., durability cycles).
8. The Sample Size for the Training Set
- Not applicable. This is a physical medical device. The "training" for this device would be the extensive research, development, and testing conducted on the original clear lens (K954524) to establish its safety and effectiveness.
9. How the Ground Truth for the Training Set Was Established
- Not applicable. As above, this is a physical medical device. The "ground truth" for the original clear lens was established through:
- "Non-clinical studies" for the clear lenses run in 1995 (referenced in 7.4 Compatibility).
- Extensive toxicology, physical/optical characteristics, and microbiology studies conducted for the original 510(k) K954524.
- These studies would have involved scientific methods, laboratory tests, and adherence to relevant standards and guidance documents (e.g., "Shelf Life of Medical Devices-April 1991 and Premarket Notification Guidance Document for Daily Wear Contact Lenses-May 1994" mentioned in 7.5 Shelf Life).
§ 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.