(28 days)
Oxycon (wilofocon A) Rigid Gas Permeable, Spherical, Aspherical, Toric, and Bifocal Contact Lenses are indicated for daily wear correction of refractive ametropia (myopia, hyperopia, astigmatism and presbyopia) in aphakic and nonaphakic persons with non-diseased eyes. The lens may be disinfected using a chemical disinfection system only.
The Oxycon (wilofocon A) Rigid Gas Permeable Contact Lens is available as a spherical, aspherical, and astigmatic (toric) lens. The lens material, wilofocon A, is a fluoro silicone acrylate polymer which contains D&C Green No. 6 as a color additive. The Oxycon (wilofocon A) Contact Lens is a hemispherical shell.
The provided text describes the characteristics of the Oxycon™ RGP Contact Lens and a clinical study conducted to support its safety and effectiveness. However, it does not explicitly define specific numerical acceptance criteria for device performance (e.g., "visual acuity must improve by X lines for Y% of patients"). Instead, the study reports observed outcomes and concludes whether these outcomes are within "expecteds" for RGP contact lens wearers.
Therefore, I will interpret "acceptance criteria" based on the qualitative conclusions drawn from the clinical study, as these represent the implicit criteria for the device's acceptance. The reported device performance will be derived directly from the study's findings.
Acceptance Criteria and Reported Device Performance (Oxycon™ RGP Contact Lens)
1. A table of acceptance criteria and the reported device performance
| Acceptance Criteria Category | Qualitative Acceptance Criteria (Inferred from Study Conclusions) | Reported Device Performance (from Clinical Study) |
|---|---|---|
| Safety (Adverse Events) | No adverse reactions requiring treatment. | "There were no eyes that experienced adverse reactions, SLFs requiring treatment or SPCs requiring treatment." |
| Safety (Slit-Lamp Findings - SLFs) | Slit-lamp findings (e.g., corneal staining, injection) should be within expected ranges for RGP lens wearers and resolve with lens changes if Grade 2. | Total of 99 Grade 1 SLFs (mostly corneal staining, 18% of visits). 5 Grade 2 SLFs (all staining), resolved by lens changes. "The total number of slit-lamp findings were within expecteds for wearers of an RGP contact lens." |
| Safety (Symptoms, Problems, Complaints - SPCs) | Symptoms, problems, or complaints (e.g., variable vision, lens awareness) should be within expected ranges for RGP lens wearers and reduce over time. | Total of 135 SPC reports (variable vision 8.7%, lens awareness 6.2%). "All symptoms, problems or complaints were reduced over time." "None of the categories for symptoms, problems, and complaints can be considered outside of the normal expecteds for a rigid gas permeable contact lens." |
| Effectiveness (Keratometry) | Keratometry changes should be generally low and attributable to adaptation or measurement variation. | Majority (90.4%) showed no change to 0.50 diopters change. 90.6% showed 1.00 diopter or less change. Average change of 0.08 diopters flattening. 3 patients showed >1.00 diopter change (two -1.25 D, one +1.25 D), with no change in 20/20 VA. "The changes in keratometry were generally low and may be attributed to adaptation to a new lens type or usual clinical measurement variation." |
| Effectiveness (Refraction) | Refraction changes should be generally low and attributable to better fit or measurement variation. | Majority (99.1%) showed no change to 1.00 diopters change. Average change near zero. 2 patients showed >1.00 diopter change (one +1.50 D sphere, one -1.50 D cylinder in both eyes). These had no change in 20/20 VA. "The changes in refraction were generally low and may be attributed to a better fitting lens or usual clinical measurement variation." |
| Effectiveness (Visual Acuity) | No patient should experience a drop in visual acuity greater than one line. | "There were no patients who experienced a drop of visual acuity that was greater than one line during the course of this study." "Visual acuity results when wearing Oxycon Rigid Gas Permeable Contact Lenses during the course of this investigation were found to be within expecteds." |
| Wearing Time | Acceptable average daily wearing time. | Average wearing time achieved at the end of the study was 14.9 hours. |
| Overall Safety & Wearability | Device shown to be worn safely. | "The Oxycon rigid gas permeable contact lens was shown to be worn safely by all patient eyes in this study including those that completed (110 eyes) and discontinued (12 eyes) the study." |
2. Sample size used for the test set and the data provenance
- Sample size for the test set: A total of 122 eyes were enrolled in the clinical study. 110 eyes completed at least three months of wear, and 12 eyes were discontinued.
- Data provenance: The data is from a prospective clinical study. The country of origin of the data is not explicitly stated, but the submission is to the U.S. FDA, suggesting the study was likely conducted in the U.S. or under U.S. regulatory standards.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
The document does not explicitly state the number or qualifications of medical experts (e.g., ophthalmologists, optometrists) who conducted the clinical examinations to establish the "ground truth" (i.e., measured outcomes) for the test set. It implies that trained clinical staff performed the assessments (e.g., slit-lamp examinations, keratometry, refraction, visual acuity checks).
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
The document does not describe any specific adjudication method for the test set data (e.g., multiple independent readers reviewing cases to resolve discrepancies). The clinical data seems to be collected and reported by the attending clinical investigator(s).
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
No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This study is for a contact lens, not an AI-powered diagnostic or assistive device. Therefore, there is no discussion of human readers improving with or without AI assistance.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
No, a standalone performance study (algorithm only) was not done. This study assesses the performance of a physical contact lens worn by human subjects, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
The "ground truth" for the device's performance was established through direct clinical observation and measurement of physiological and visual parameters in human subjects by clinical investigators. This includes:
- Visual acuity measurements
- Slit-lamp examination findings (for corneal staining, injection, etc.)
- Subjective patient reports of symptoms, problems, and complaints (SPCs)
- Keratometry measurements
- Refraction measurements
These are "outcomes data" derived from clinical examinations rather than expert consensus on retrospective images or pathology reports.
8. The sample size for the training set
The document describes a clinical study for device approval. It does not mention a "training set" in the context of an algorithmic or AI-based device. The 122 enrolled eyes constitute the clinical study population used to demonstrate safety and effectiveness.
9. How the ground truth for the training set was established
As there is no mention of a "training set" in the context of an algorithmic device, this question is not applicable to the provided document. The clinical study was designed to evaluate the physical contact lens directly in patients.
§ 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.