(79 days)
ADK (Automated Disposable Keratome) is intended to perform anterior, lamellar, circular corneal resections of a predetermined diameter and thickness.
The Automated Disposable Keratome consists of two components: (a) disposable keratome, (b) power / suction supply and DC motor with foot actuated switch. The ADK is a keratome designed to perform anterior lamellar circular corneal resections of a predetermined diameter and thickness based upon the principle of a carpenter's plane. A cutting blade emerges from the center of the keratome plane. The stainless steel blade oscillates by a small DC motor controlled by foot switch. The keratome, which is fabricated from high density engineering plastic (except the blade and motor), has a one piece head that is pre-assembled with a fixed foot plate, and is available in two standard head sizes, 130 or 160 microns, depending upon the thickness of corneal section desired. The keratome head has dovetail guides, which correspond to guides on the suction ring that is placed upon the ocular globe. Tandem gears on both sides of the keratome head and corresponding gears on the suction ring automatically move the cutting blade along the dovetail guides. Whereas gears on competitive keratomes are exposed, the gears on the ADK are covered to minimize entrapment of lashes and lids. A DC motor controls the gears and blade movement via the foot switch control. The cutting principle is the same as with manual keratomes and other automated keratomes. The automatic movement of the keratome allows for a more uniform translation across the suction ring and thusly across the cornea. The power supply provides the power to both the keratome motor and the suction supply for holding the suction ring in place on the cornea. The ADK has three settings for vacuum control: "off", "low", "high"; whereas predicate devices have only two vacuum settings, "on" and "off". The vacuum suction of predicate devices in the "on" position is the same as the suction of the "high" setting of the ADK. The "low" suction setting of the ADK provides the option of using the suction ring to aid in globe fixation after the resection. Predicate devices require the surgeon to use the "off" position for globe fixation after resection, where residual suction declines variably back to 0 mmHg. The keratome is provided sterile in a sealed blister/Tyvek® tray and is discarded after single use.
Here's an analysis of the provided 510(k) summary regarding acceptance criteria and supporting studies for the Automated Disposable Keratome (ADK):
It's important to note that this document is a 510(k) summary, not a full pre-market approval application. 510(k) submissions typically focus on demonstrating substantial equivalence to a legally marketed predicate device rather than presenting extensive clinical efficacy data as would be required for a novel, high-risk device. Therefore, the information provided reflects this regulatory pathway.
No explicit "acceptance criteria" for performance metrics are defined in this document, nor is there a detailed clinical study demonstrating the device meets specific numerical performance targets. The submission relies on substantial equivalence to predicate devices and general safety and effectiveness.
However, we can infer the implied acceptance criteria and the types of evidence used to support them.
Inferred Acceptance Criteria and Reported Device Performance
Given the nature of the 510(k) submission, the "acceptance criteria" are largely derived from the substantial equivalence concept and the demonstrated safety and effectiveness of the predicate devices. The "reported device performance" is descriptive, highlighting how the ADK maintains or improves upon these characteristics.
| Acceptance Criteria (Inferred from Substantial Equivalence) | Reported Device Performance (ADK) |
|---|---|
| Similar Intended Use: Perform anterior lamellar circular corneal resections of a predetermined diameter and thickness. | Meets: The ADK is intended to shave a partial lamellar section of the cornea, fulfilling the same intended use. |
| Similar Technological Characteristics: Operates on the same principles (carpenter's plane, oscillating blade, DC-powered gear drive), similar power supply, blade oscillation, and vacuum control mechanism as predicate keratomes. | Meets/Improves: Uses the same cutting principle, DC-powered gear drive design (proven safe and effective), 110/120 AC electrical, 10,000 RPM motor, and AC-powered vacuum pump. |
| Improvements: |
- Dual Parallel Drive Action: Adds a second gear and track to reduce torque-induced jamming (a potential drawback of single-sided drives like the Chiron ACS).
- Covered Gears: Minimizes entrapment of lashes and lids, addressing a potential issue with exposed gears on competitive models.
- Three Vacuum Settings ("low" option): Allows for globe fixation after resection, providing better control than predicate devices with only "on/off" settings. |
| Biocompatibility: Device materials are not toxic or irritating to ocular tissue. | Meets: High-density plastic materials, excluding the stainless steel blade, have been tested according to FDA Tripartite Guidelines and ISO 10993-1 Standard and are deemed biocompatible. |
| Sterility: Device can be provided sterile and maintain sterility. | Meets: Provided sterile in a sealed blister/Tyvek® tray, sterilized under a validated gamma irradiation cycle with a SAL of 10⁻⁶, and dosimetric release. |
| Electrical Safety: Conforms to electrical safety standards. | Meets: The ADK power supply conforms to the IEC-601-1 electrical safety standard. |
| Elimination of "Drawbacks" of Predicate Devices: Addresses issues associated with cleaning, re-assembly, component wear, and potential tissue jamming. | Meets: The ADK is pre-assembled, pre-sterilized, and disposable after single use, directly addressing human error during cleaning/assembly/wear, and reducing the potential for tissue jamming by covering gears. |
| Clinical Safety and Effectiveness: Associated with acceptable clinical results in terms of postoperative refraction and visual acuity, and minimal postoperative complications (as demonstrated by long-term use of predicate devices). (This is extrapolated from the general acceptance of keratomes over time). | Supported by Predicate History: A review of published literature on keratomes indicates acceptable clinical results and minimal complications. The ADK's design changes are argued not to affect safety and effectiveness as they do not alter the energy source, cutting parts, or principle of operation, but rather improve usability and reduce potential user-related errors. |
Study Information & Details:
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A table of acceptance criteria and the reported device performance: (See above table)
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Sample size used for the test set and the data provenance:
- No specific test set of patient data or clinical trial with a defined sample size is mentioned or reported for the ADK.
- The submission relies heavily on the historical performance and safety of its predicate devices (Automatic Corneal Shaper, Steinway-Barraquer In-Situ Microkeratome Set, Micro Refractive System Model 1000).
- The "evidence" is primarily based on a literature review regarding the general clinical acceptance of keratomes over 30-45 years, rather than a prospective study on the ADK itself.
- Provenance: "Published literature on keratomes," implying retrospective data from various sources (not specified, but likely international given medical literature) reflecting decades of use.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable. There was no specific "test set" and thus no experts were used to establish ground truth for a novel assessment of the ADK in this submission as typically seen in efficacy trials.
- The "experts" indirectly involved are the broader ophthalmic community whose published literature established the historical safety and efficacy of keratomes, which forms the basis of the substantial equivalence argument.
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Adjudication method for the test set:
- Not applicable. No test set or clinical outcomes requiring adjudication were presented for the ADK.
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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:
- Not applicable. This device is a surgical instrument (keratome), not an AI-powered diagnostic or assistive tool. MRMC studies are not relevant here.
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If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- Not applicable. This is a hardware surgical instrument. Performance is always "human-in-the-loop," as a surgeon operates it. The device itself does not perform any task "stand-alone" in a diagnostic or analytical sense.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- The "ground truth" for the overall class of devices (keratomes) is established through historical clinical outcomes data from decades of use, supported by expert consensus reflected in the published literature.
- For the ADK specifically, the ground truth for its design changes relies on engineering principles (e.g., dual parallel drive reduces torque, covered gears prevent entanglement), biocompatibility testing (ISO 10993-1), and sterilization validation (gamma irradiation).
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The sample size for the training set:
- Not applicable. No "training set" in the context of machine learning or deep learning was used. The device is a mechanical instrument.
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How the ground truth for the training set was established:
- Not applicable. As no training set was used, no ground truth needed to be established for it.
§ 886.4370 Keratome.
(a)
Identification. A keratome is an AC-powered or battery-powered device intended to shave tissue from sections of the cornea for a lamellar (partial thickness) transplant.(b)
Classification. Class I.