(124 days)
The Menicon Z (tisilfocon A) Rigid Gas Permeable Contact Lenses are indicated for the correction of refractive ametropia (myopia, hyperopia, astigmatism and presbyopia) in aphakic or not-aphakic persons with non-diseased eyes.
The lenses may be prescribed in otherwise non-diseased eyes that require a rigid contact lens for the management of irregular corneal conditions such as keratoconus, pellucid marginal degeneration, or following penetrating keratoplasty or refractive (e.g. LASIK) surgery.
The lenses may be disinfected using a chemical disinfection system only.
The Menicon Z lens material, tisilfocon A is a thermoset copolymer derived from fluoromethacrylate and siloxanylstyrene, bound by crosslinking agents. The lens is tinted light blue with color additive D&C Green No. 6 (21 CFR 74.3206). Also, UV absorber (benzotriazol) is added.
Lens designs for the management of irregular corneas include: 1) progressively flattening peripheral curves, 2) a reverse curve or series of reverse curves in the peripheral design, or 3) decentered optic zone and resulting peripheral curves, or 4) a combination of the first three systems.
The provided 510(k) summary for the Menicon Z (tisilfocon A) Rigid Gas Permeable Contact Lenses does not contain specific acceptance criteria, nor does it describe a study designed to prove the device meets such criteria in the way typically expected for novel devices demonstrating performance metrics.
Instead, the submission relies on the concept of substantial equivalence to predicate devices and previously cleared or approved applications for the same material.
Therefore, the following information is not present in the provided text:
- A table of acceptance criteria and reported device performance.
- Sample sizes used for a test set, data provenance, number of experts for ground truth, adjudication method, MRMC study details, or standalone study details related to the performance of the device against specific criteria.
- The type of ground truth used for such a study.
- Sample size for a training set or how ground truth for a training set was established.
Here's an analysis based on the available information:
1. Acceptance Criteria and Reported Device Performance
The submission does not define specific performance acceptance criteria for the Menicon Z lenses in terms of efficacy or safety metrics. Instead, "acceptance" is based on substantial equivalence to predicate devices and previously cleared/approved applications for the material (tisilfocon A).
The reported device performance is summarized qualitatively:
"Results of a retrospective case study using the Menicon Z lenses for the management of keratoconus and other irregular corneal conditions demonstrated that the lenses effectively maintained corneal physiology and visual acuity."
This statement acts as the performance claim, but it's not tied to specific, quantifiable acceptance criteria.
2. Sample Size Used for the Test Set and Data Provenance
The document mentions a "retrospective case study," but it does not provide any details regarding:
- The sample size of this study.
- The country of origin of the data.
- Whether the study was retrospective or prospective (though it explicitly states "retrospective").
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
This information is not provided. The "retrospective case study" is mentioned, but the methodology for establishing "ground truth" (e.g., what constitutes "maintained corneal physiology" or "effectively maintained visual acuity") and who assessed it is not detailed.
4. Adjudication Method (e.g., 2+1, 3+1, none) for the Test Set
This information is not provided.
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
An MRMC study is not mentioned in this 510(k) summary. This type of study is typically relevant for AI/CADe devices, which this contact lens is not.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
This is not applicable as the device is a physical contact lens, not an algorithm.
7. The Type of Ground Truth Used
The "ground truth" for the retrospective case study would likely have been clinical assessments by ophthalmologists or optometrists, focusing on:
- Corneal physiology: Assessed through slit lamp examination, fluorescein staining, etc., to check for signs of hypoxia, edema, infiltrates, or other adverse events.
- Visual acuity: Measured using standard Snellen charts or equivalent.
However, the specific methods or whether this was expert consensus, pathology, or outcomes data is not explicitly stated.
8. The Sample Size for the Training Set
A "training set" isn't applicable in the context of this submission. The device is a physical product based on a known material, not an AI algorithm. The material itself has been previously studied and cleared/approved.
9. How the Ground Truth for the Training Set was Established
This is not applicable as there is no "training set" in the context of this device.
Summary of the Study and its Role in Acceptance:
The core of the submission for Menicon Z (tisilfocon A) Rigid Gas Permeable Contact Lenses relies on:
- Substantial Equivalence: The primary basis for clearance is that the Menicon Z material (tisilfocon A) has been previously cleared/approved in multiple 510(k)s (K962006, K970019) and PMAs (P990018, P990018/S002) for various wear durations and designs. This implies its safety and basic efficacy (biocompatibility, oxygen permeability, etc.) are already established.
- Predicate Devices: The device is considered substantially equivalent to other legally marketed RGP lenses for the correction of refractive ametropia and for the management of irregular corneal conditions (e.g., Rose K Post Graft, Dyna Intra-Limbal, Boston XO/EO/ES). This means the FDA found that the Menicon Z lens is as safe and effective as these existing devices, and does not raise new questions of safety or effectiveness.
- Retrospective Case Study (for Irregular Corneas Indication):
- Purpose: To support the additional indication for the management of irregular corneal conditions (e.g., keratoconus, post-surgical).
- Finding: The study "demonstrated that the lenses effectively maintained corneal physiology and visual acuity."
- Details Missing: Specific details about the study (sample size, exact metrics, and ground truth establishment) are not provided in this summary. However, the FDA's acceptance of this statement implies they found it sufficiently supportive for the expanded indication, likely in conjunction with the established safety profile of the material.
- Clinical Study Necessity: The document explicitly states: "Clinical study for the Menicon Z (tisilfocon A) material has been deemed as not necessary in support of this clearance, as no new or additional questions of safety or effectiveness have been raised." This indicates that the retrospective case study was likely a supportive piece of evidence rather than a primary, meticulously designed clinical trial to establish new safety/efficacy metrics from scratch.
§ 886.5916 Rigid gas permeable contact lens.
(a)
Identification. A rigid gas permeable contact lens is a device intended to be worn directly against the cornea of the eye to correct vision conditions. The device is made of various materials, such as cellulose acetate butyrate, polyacrylate-silicone, or silicone elastomers, whose main polymer molecules generally do not absorb or attract 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.