(385 days)
The Boston Keratoprosthesis is indicated to provide a transparent optical pathway through an opacified cornea in an eye that is not a reasonable candidate for any form of corneal transplant, including penetrating keratoplasty.
The Boston Keratoprosthesis is an artificial corneal device that can be used in patients with severe corneal opacity. The Boston Keratoprosthesis is used after standard corneal transplant has failed or when such a transplant would be unlikely to succeed. Thus, keratoprosthesis implantation is a procedure designed to help patients whose conditions are the most difficult to treat. This 510(k) seeks to modify the back plate material from PMMA to titanium. In doing so, the modified implant eliminates the need for a titanium retaining ring which was employed in the predecessors to hold the PMMA back plate in position following implantation. This also simplifies the assembly. It is available in two types. The Type I keratoprosthesis is implanted through and fixed only to the cornea and is used for corneal blindness when the eyelids, blink mechanism and tear film are intact. The Type II keratoprosthesis has an anterior extension to enable implantation through an opening in the closed eyelids. The Type II device is used in eyes with severe dry eye, mucosal keratinization and obliteration of the normal conjunctival fornices, such as after severe chemical injuries or Stevens Johnson syndrome or mucous membrane pemphigoid. Both devices are identical in terms of assembly.
Here's a breakdown of the acceptance criteria and study information for the Boston Keratoprosthesis, based on the provided document:
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state quantitative acceptance criteria in terms of specific performance metrics (e.g., visual acuity targets, failure rates, etc.). Instead, the primary acceptance criterion is substantial equivalence in safety and effectiveness compared to the predicate device.
| Acceptance Criterion (Implicit) | Reported Device Performance (Titanium Back Plate) |
|---|---|
| Safety: The modified device (titanium back plate) is as safe as the predicate device (PMMA back plate), with no new issues of safety raised. This is assessed through biocompatibility and a comparison of adverse events/complications. | Clinical data shows the titanium back plate is "as safe" as the predicate PMMA back plate. Non-clinical testing demonstrates the titanium version is biocompatible. |
| Effectiveness: The modified device is as effective as the predicate device, providing a transparent optical pathway in the intended patient population. This is assessed by comparing outcomes. | Clinical data shows the titanium back plate is "as effective" as the predicate PMMA back plate. The device fulfills prospectively defined performance criteria, and the modified system meets user needs. |
| Biocompatibility: The new material (titanium) is biocompatible. | Non-clinical testing demonstrates that the titanium version is biocompatible. |
| Similar Assembly Strength Profiles: The change in material does not negatively impact the structural integrity of the device. | Non-clinical testing demonstrates the titanium version possesses similar assembly strength profiles to the PMMA version. |
| Manufacturability/Sterility/Shelf Life: The manufacturing process, sterilization, and shelf life are acceptable. | Validation activities included Sterility Validation, Bioburden, LAL, MRI Compatibility, and Shelf Life Testing. (Presumed successful, as equivalence was affirmed). |
| No new issues of safety and effectiveness: The design differences do not introduce unforeseen problems. | All data collected confirms that the differences in the design of the Boston Keratoprosthesis with titanium back plate do not raise any new issues of safety and effectiveness when compared to the predicate design. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size (Clinical Performance Data):
- Modified Titanium Back Plate Device: 86 eyes in 86 subjects
- Predicate PMMA Device: 55 eyes in 50 subjects
- Data Provenance: The document does not explicitly state the country of origin. Given the sponsor is "Massachusetts Eye & Ear Infirmary," it is highly probable the data is from the United States. The study is described as having a "mean follow-up of 14.8 months with a maximum follow-up of 38 months," indicating a prospective collection of follow-up data post-implantation for these cohorts, although the specific start date relative to the device modification isn't given.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications
The document does not mention experts being used to establish "ground truth" in the way one would for an AI diagnostic device (e.g., image interpretation). This device is a surgical implant; its performance is assessed through clinical outcomes and physical properties. Therefore, there's no "ground truth" derived from expert image interpretation in this context.
4. Adjudication Method for the Test Set
Not applicable. As this is not an AI diagnostic device and there's no expert "ground truth" to adjudicate for a test set of data points, there is no mention of an adjudication method. Clinical outcomes would typically be recorded by treating physicians.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No. This is not an AI diagnostic device, so an MRMC study comparing human readers with and without AI assistance is not relevant or reported.
6. Standalone (Algorithm Only) Performance Study
No. This is not an AI algorithm. It's a physical medical device (an implant). Therefore, a standalone performance study in the context of an algorithm is not applicable.
7. Type of Ground Truth Used
The "ground truth" for this device's performance is established through clinical outcomes data (e.g., safety profiles, effectiveness in providing a transparent optical pathway, long-term follow-up results) and non-clinical engineering testing (e.g., biocompatibility, assembly strength, sterility, shelf life). The key is demonstrating that the modified device's performance is "as safe and effective" as the predicate device.
8. Sample Size for the Training Set
Not applicable. This is not an AI algorithm, so there is no "training set."
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no training set.
§ 886.3400 Keratoprosthesis.
(a)
Identification. A keratoprosthesis is a device intended to provide a transparent optical pathway through an opacified cornea, either intraoperatively or permanently, in an eye that is not a reasonable candidate for a corneal transplant.(b)
Classification. Class II. The special controls for this device are FDA's:(1) “Use of International Standard ISO 10993 ‘Biological Evaluation of Medical Devices—Part I: Evaluation and Testing,’ ”
(2) “510(k) Sterility Review Guidance of 2/12/90 (K90-1),” and
(3) “Guidance on 510(k) Submissions for Keratoprostheses.”