(208 days)
Layer 7-T cortical electrodes are intended for temporary (less than 30 days) use with recording, monitoring, and stimulation equipment for the recording, monitoring, and stimulation of electrical signals on the surface of the brain. The electrodes may be placed in either open or burr hole procedures with the optional use of standard imaging techniques such as intraoperative x-ray, fluoroscopy, and computerized tomography (CT).
The Layer 7-T is intended for temporary (less than 30 days) use with recording, monitoring, and stimulation equipment for the recording, monitoring, and stimulation of electrical signals on the surface of the brain. The electrodes may be placed in either open or burr hole procedures with the optional use of standard imaging techniques such as intraoperative x-ray, fluoroscopy, and computerized tomography (CT).
The overall Layer 7-T consists of a sterile thin film 1024-electrode array connected to a more rigid PCB package (known as the headstage) with ribbon cables. Each ribbon cable connects to 64 channels from the electrode array. There are a total of 16 ribbon cables in the headstage, connecting 1024 electrodes on the array. The device is also provided with an intermediary yoke cable that connects the ribbon cables from the Layer 7-T headstage to standard EEG equipment via 64 standard DIN connectors. A yoke stand is also provided as an optional accessory that allows up to 16 yokes to be stacked. Surgical accessories are provided with the array and are intended to aid in deployment of the array.
The system allows the surgeon to place electrode arrays on the surface of the brain through burr holes. The inserted portion of the device can be retrieved following use by pulling the electrode array through the burr hole.
The thin film electrode array is designed to operate in a fashion identical to the currently used ECoG arrays, in that it is to be placed on the surface of the brain to interface with brain tissue through electrical recording and stimulation.
The electrode array consists of a polyimide substrate with platinum electrodes and associated electrically connecting traces and another layer of polyimide on top. A polyimide pocket is adhered via silicone to the backside of the electrode array tip. The array also contains gold radiopaque markers embedded in the silicone pocket adhesive. A rigid stainless steel radiopaque stylet is temporarily placed in the pocket during electrode array deployment.
The overall Layer 7-T system, including the yoke, is intended for single use only. The Layer 7-T is a passive device and only receives power from a connected FDA-cleared EEG system. It does not have any wireless capabilities and does not contain any software. It is not MRI-compatible. It is only intended for use in a professional healthcare environment.
The provided text is a 510(k) summary for a medical device called "Layer 7-T," a cortical electrode. While it details numerous performance tests, biocompatibility studies, electrical safety, human factors, and animal testing, it does not describe a study involving human-in-the-loop performance with an AI component or any study that would require acceptance criteria related to diagnostic accuracy, sensitivity, specificity, or reader improvement.
The document states: "The Layer 7-T is a passive device and only receives power from a connected FDA-cleared EEG system. It does not have any wireless capabilities and does not contain any software." This clearly indicates that the device itself is a passive hardware component and does not incorporate AI or any form of software that analyzes or interprets data to provide a diagnostic or assistive output that would require a "study that proves the device meets the acceptance criteria" in the context of AI performance.
Therefore, I cannot provide the requested information regarding AI acceptance criteria or a study proving device performance in that context, as the provided document explicitly states the device does not contain software or AI.
However, I can extract the general "performance data" that demonstrates the device's safety and effectiveness relative to its predicate, as described in the document.
General Performance Data and Acceptance (Based on Equivalence to Predicate)
The acceptance criteria for the Layer 7-T are implicitly defined by its ability to demonstrate substantial equivalence to the predicate device (Ad-Tech Subdural Electrodes, K191186) through various non-clinical tests. The goal is to show that it is "as safe and effective" as the predicate, even with minor technological differences.
1. Table of Acceptance Criteria and Reported Device Performance:
Since there's no AI or diagnostic software, the "acceptance criteria" for the device relate to fundamental device properties, material safety, and functional performance, with the implicit criterion being "Pass" compared to established standards or a predicate.
| Test/Parameter | Acceptance Criteria (Implicit from "Passed") | Reported Device Performance |
|---|---|---|
| Dimensional Measurements | Conform to hardware specifications by measurement and visual assessment. | Pass |
| Durability | Function safely and effectively under normal use conditions (mechanical testing). | Pass |
| Electrochemical Performance | Conductive properties appropriate for intended use; electrical continuity. | Pass |
| Platinum Dissolution Testing | Level of platinum released following stimulation protocol is acceptable. | Pass |
| Signal-to-Noise Ratio Testing | SNR comparable to the predicate. | Pass |
| Reliability | Maintain electrochemical and physical properties after accelerated aging. | Pass |
| EEG System Compatibility | Verification of signal acquired following cycling of connector. | Pass |
| Packaging Shelf Life | Pass ASTM F2096-11(2019) and ASTM D4169-23 standards. | Pass |
| Sterilization | Pass ISO 11135:2014 for ethylene oxide sterilization. | Pass |
| Biocompatibility | All assessed endpoints (Cytotoxicity, Sensitization, Irritation, Acute Systemic Toxicity, Material Mediated Pyrogenicity, Genotoxicity, Implantation Testing, Hemolysis, Chemical characterization/Toxicological Risk Assessment) are acceptable. | Results support biocompatibility. |
| Electrical Safety & EMC | Conform to IEC 60601-1 (various amendments), IEC 60601-1-2 (various amendments), IEC 80601-2-49:2018, and IEC TR 60601-4-2:2024. | Passed applicable clauses. |
| Human Factors | Usability validated per "Applying Human Factors and Usability Engineering to Medical Devices" guidance and ANSI AAMI HE75:2009. | All evaluations performed and support safety/effectiveness. |
| Animal Testing (GLP Study) | No adverse events specifically related to the Layer 7 cortical electrode array; similar cortical inflammatory response to predicate, subsiding by 6 weeks. | Confirmed biocompatibility; no ongoing neurotoxicity; similar inflammatory response to predicate. |
2. Sample Size Used for the Test Set and Data Provenance:
The document describes non-clinical bench testing and animal studies. There is no "test set" in the context of an AI model's performance on patient data.
- Bench Testing: Sample sizes are not explicitly stated for most bench tests (e.g., durability, electrochemical performance), but it's implied that sufficient samples were tested to demonstrate compliance.
- Animal Testing: 16 female Göttingen swine were used, divided into a 1-week and a 6-week implant duration cohort.
- Data Provenance: The animal study was a GLP (Good Laboratory Practices) study, indicating a controlled, prospective experimental setting. The origin of the animals is not specified beyond "Göttingen swine."
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:
Not applicable, as this is neither an AI device nor does it involve a "test set" requiring expert-established ground truth in the diagnostic sense. The ground truth for biocompatibility and animal study outcomes would be established by qualified pathologists and veterinarians, but their specific number and qualifications are not detailed.
4. Adjudication Method for the Test Set:
Not applicable, as there's no AI model output requiring adjudication.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done:
No, an MRMC study was not performed. This type of study is typically used for AI-assisted diagnostic devices to assess the impact of AI on human reader performance, which is not relevant for this passive hardware device.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:
Not applicable, as the device is a passive hardware component with no embedded algorithm or software for standalone performance evaluation beyond its physical and electrical characteristics.
7. The Type of Ground Truth Used:
- Bench Testing: Ground truth is based on engineering specifications, physical measurements, and adherence to international standards (e.g., ASTM, ISO, IEC).
- Animal Testing: Ground truth was established through neurological evaluations, gross and microscopic pathological analysis performed by qualified personnel (implied).
8. The Sample Size for the Training Set:
Not applicable, as there is no AI or machine learning model that requires a training set.
9. How the Ground Truth for the Training Set Was Established:
Not applicable, as there is no AI or machine learning model.
§ 882.1310 Cortical electrode.
(a)
Identification. A cortical electrode is an electrode which is temporarily placed on the surface of the brain for stimulating the brain or recording the brain's electrical activity.(b)
Classification. Class II (performance standards).