(15 days)
The Nexus Detachable Coils are intended for the endovascular embolization of intracranial aneurysms that -- because of their morphology, their location, or the patient's general medical condition - are considered by the treating neurosurgical team to be a) very high risk for management by traditional operative techniques, or b) be inoperable. The Nexus Detachable Coils are also intended for the embolization of other neuro vascular abnormalities, such as, arteriovenous malformations and arteriovenous fistulae.
The Nexus coils are platinum alloy coils, enlaced with absorbable polymer fibers, and attached to a stainless steel guiding system with a radiopaque positioning coil. Nexus coils are designed for use with the NXT Detachment System specifically designed for coil detachment. The NXT Detachment System is sold separately.
The provided text describes a 510(k) submission for the Nexus Multi-Diameter CSR and Helix Super Soft CSR neurovascular embolization devices. This document focuses on demonstrating substantial equivalence to a predicate device through bench testing rather than reporting on a study involving human or animal subjects that would result in performance metrics like sensitivity, specificity, or reader improvement. Therefore, many of the requested elements for a study on device performance and acceptance criteria (e.g., sample size for test/training set, number of experts, adjudication method, MRMC studies, standalone performance, ground truth types) are not applicable or cannot be extracted from this specific document.
The acceptance criteria are generally "Met established criteria" for various bench tests. The "study" that proves the device meets these criteria is the bench testing itself, as summarized in the Verification and Test Summary Table.
Here's the information that can be extracted and a note on what cannot be provided based on the input text:
1. Table of acceptance criteria and the reported device performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Coil Deformation (Established Criteria) | Met established criteria |
| Dimensional & Visual Analysis (Established Criteria) | Met established criteria |
| Coating Integrity (Established Criteria) | Met established criteria |
| Force Transfer (Established Criteria) | Met established criteria |
| Ease of Delivery/Coil Frictional Characteristics (Established Criteria) | Met established criteria |
| Fiber Endurance Testing (Established Criteria) | Met established criteria |
| Reliability After Fatigue & Premature Detachment (Established Criteria) | Met established criteria |
| Fiber Pull-Out (Established Criteria) | Met established criteria |
| Tensile Strength (Established Criteria) | Met established criteria |
| Particulate Generation - Adjusted Particles / 1 mL (Established Criteria) | Met established criteria |
| PGLA Tensile Testing (Established Criteria) | Met established criteria |
| Packaging Integrity (Established Criteria) | Met established criteria |
2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Sample Size for Test Set: Not specified in the provided text. The text only mentions "Bench Testing" with various categories of tests, but does not provide details on the number of coils or samples tested for each category.
- Data Provenance: Not applicable. The data comes from internal bench testing conducted by the manufacturer, Micro Therapeutics, Inc., located in Irvine, California, USA. This is an engineering/materials-based evaluation, not a clinical study involving patient data.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
Not applicable. Ground truth in this context refers to engineering specifications and performance benchmarks, not clinical expert consensus. The "ground truth" for the acceptance criteria would be the pre-defined engineering and performance specifications set by Micro Therapeutics, Inc.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable. Adjudication methods are typically relevant for clinical studies where expert consensus is needed to resolve discrepancies in diagnoses or interpretations. Bench testing involves objective measurements against established criteria.
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 document does not mention any MRMC study. The device is a physical medical implant (coil), not an AI diagnostic tool.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This device is a physical medical device, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
The "ground truth" for this device's evaluation is based on pre-defined engineering specifications and performance standards for physical characteristics, material integrity, and functional attributes relevant to the device's intended use. This is a technical/engineering ground truth for bench testing.
8. The sample size for the training set
Not applicable. This document describes a 510(k) submission for a physical medical device, relying on bench testing to demonstrate substantial equivalence. There is no "training set" in the context of machine learning or AI.
9. How the ground truth for the training set was established
Not applicable. As there is no training set mentioned or implied in this submission, the method for establishing its ground truth is irrelevant.
§ 882.5950 Neurovascular embolization device.
(a)
Identification. A neurovascular embolization device is an intravascular implant intended to permanently occlude blood flow to cerebral aneurysms and cerebral ateriovenous malformations. This does not include cyanoacrylates and other embolic agents, which act by polymerization or precipitation. Embolization devices used in other vascular applications are also not included in this classification, see § 870.3300.(b)
Classification. Class II (special controls.) The special control for this device is the FDA guidance document entitled “Class II Special Controls Guidance Document: Vascular and Neurovascular Embolization Devices.” For availability of this guidance document, see § 882.1(e).