(38 days)
The Modified Merci® Retriever is intended to restore blood flow in the neurovasculature by removing thrombus in patients experiencing ischemic stroke. Patients who are ineligible for intravenous tissue plasminogen activator (IV t-PA) or who fail IV t-PA therapy are candidates for treatment. The Modified Merci® Retriever is also indicated for use in the retrieval of foreign bodies misplaced during interventional radiological procedures in the neuro, peripheral and coronary vasculature.
Like the predicate device, the Modified Merci Retriever consists of a flexible, Nitinol core wire with shaped loops at the distal end. A radiopaque coil covers the tip allowing visualization under fluoroscopy.
Both the predicate Retriever and the Modified Merci Retriever are placed distal to the thrombus or foreign body using a microcatheter which is retracted to deploy the loops of the Retriever. The Retriever and microcatheter are pulled back into the thrombus or foreign body, engaging it in the loops of the Retriever. The Retriever, the thrombus or foreign body, and the microcather are then removed from the body.
This document is a 510(k) summary for the Concentric Medical, Inc. Modified Merci Retriever. It aims to demonstrate substantial equivalence to the predicate device, the Merci® Retriever X6, rather than proving the device meets specific acceptance criteria through a clinical study. Therefore, most of the requested information regarding study design, sample sizes, expert involvement, and ground truth establishment is not present in this document.
Here's an analysis based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance:
The document does not provide a table of specific, quantifiable acceptance criteria or reported device performance in the context of typical clinical study results (e.g., sensitivity, specificity, accuracy, workflow time, etc.). Instead, it states that the device was tested and found to meet "required specifications."
| Acceptance Criteria (Not Explicitly Stated) | Reported Device Performance |
|---|---|
| Functional Equivalence to Predicate Device (Merci® Retriever X6): Implicit expectation that the Modified Merci Retriever performs as well as or better than the predicate in all critical functions. | "All devices met the required specifications for the completed tests." |
| Material Suitability: Implicit expectation that materials are safe and effective for intended use. | "All materials used in the manufacture of the Modified Merci Retriever are suitable for the intended use of the device and have been used in numerous previously cleared products." |
| Design Compliance: Implicit expectation that the device adheres to quality system regulations. | "The Modified Merci Retriever was designed under the Concentric Quality System in compliance with 21CFR 8820.30." |
| Intended Use Equivalence: Implicit expectation that the new device supports the same indications. | "The Modified Merci Retriever is equivalent to the predicate device, Merci® Retriever X6. The indications for use, function, and materials used are substantially equivalent." |
2. Sample size used for the test set and the data provenance:
- Sample Size: Not specified. The document indicates "All devices" were tested, implying all manufactured units or a representative sample from a production lot were subjected to engineering/performance tests, but no test set in the context of clinical data is mentioned.
- Data Provenance: Not applicable. The testing described appears to be engineering and design verification, not clinical data from patients or a specific geographical region.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable. The document describes product testing (design verification, material suitability) rather than a study requiring expert-established ground truth for clinical cases.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not applicable. There is no mention of clinical data or adjudication processes.
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. This is a 510(k) submission for a medical device (thrombus retriever), not an AI diagnostic tool. Therefore, an MRMC study related to AI performance is not relevant or included.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Not applicable. This is not an AI algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Not explicitly stated for clinical ground truth. For the engineering tests, the "ground truth" would be the predefined specifications and performance metrics for the device (e.g., tensile strength, flexibility, material composition, deployment mechanism integrity), which are internally established by the manufacturer and often align with industry standards or recognized test methods.
8. The sample size for the training set:
- Not applicable. There is no mention of a "training set" as this is not a machine learning or AI product.
9. How the ground truth for the training set was established:
- Not applicable for the same reason as above.
Summary of the Study (as described):
The "study" described in the document is a design verification and validation process for the Modified Merci Retriever. It is a comparison to a predicate device (Merci® Retriever X6) to establish substantial equivalence.
- Study Type: Design verification and validation.
- Objective: To demonstrate that the Modified Merci Retriever is substantially equivalent to the predicate device (Merci® Retriever X6) in terms of indications for use, function, materials, and safety/performance.
- Methodology: The device underwent "the same manner" of testing as the predicate device. This implies a series of internal engineering and performance tests (e.g., mechanical tests, material compatibility tests, deployment tests in a simulated environment) to ensure the device meets its design specifications and performs comparably to the predicate.
- Conclusion: The manufacturer concluded that "All devices met the required specifications for the completed tests" and that the Modified Merci Retriever is "substantially equivalent" to the predicate device.
This 510(k) summary focuses on demonstrating that the new device does not raise new questions of safety or effectiveness compared to a previously cleared device, which is the standard for 510(k) submissions. It does not provide detailed clinical trial data or performance metrics from a large patient cohort, as would be expected for a novel device or an AI clinical decision support tool.
§ 870.1250 Percutaneous catheter.
(a)
Identification. A percutaneous catheter is a device that is introduced into a vein or artery through the skin using a dilator and a sheath (introducer) or guide wire.(b)
Classification. Class II (performance standards).