(42 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 medical device, the Nexus Morpheus 3D CSR, and its premarket notification (510(k)) submission to the FDA. The submission focuses on establishing substantial equivalence to a predicate device, the Nexus Tetris 3D CSR, rather than proving the device meets acceptance criteria through a study demonstrating performance metrics in a clinical setting against a defined ground truth.
Therefore, many of the requested details related to a performance study (like sample size, data provenance, expert ground truth, MRMC study, standalone performance, training set details) are not applicable or not present in the provided document, as it describes a different type of regulatory submission. The verification and test summary focuses on bench testing to ensure the new device functions similarly to the predicate.
Here's an attempt to answer based on the available information:
1. Table of Acceptance Criteria and Reported Device Performance
For this 510(k) submission, the "acceptance criteria" are the established engineering and functional benchmarks for the device, and "reported device performance" indicates whether these benchmarks were met.
| Bench Testing Acceptance Criteria | Reported Device Performance |
|---|---|
| Coil Deformation met established criteria | Met established criteria |
| Dimensional & Visual Analysis met established criteria | Met established criteria |
| Ease of Delivery/Coil Frictional Characteristics met established criteria | Met established criteria |
| In Vitro Aneurysm Fills and Reliability After Fatigue met established criteria | Met established criteria |
| Microfilament Pull-Out met established criteria | Met established criteria |
| Tensile Strength met established criteria | Met established criteria |
2. Sample size used for the test set and the data provenance
The document does not specify sample sizes for these bench tests. The data provenance is internal testing performed by Micro Therapeutics, Inc. (DBA ev3 Neurovascular) on the device components. This is not clinical data, but rather engineering and material testing.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
Not applicable. Ground truth as typically defined for clinical performance studies (e.g., expert consensus on medical images or pathology results) is not relevant for the bench testing described. The "ground truth" here would be engineering specifications and standards.
4. Adjudication method for the test set
Not applicable. This was bench testing against predefined engineering criteria, not a subjective assessment requiring adjudication.
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 medical device (neurovascular embolization coil), not an AI diagnostic or assistance system. Therefore, an MRMC study related to AI assistance is not applicable.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
No. This is a physical medical device. "Standalone" performance in this context refers to the device's functional integrity during bench testing, not an algorithm's performance.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
The "ground truth" for the bench tests would have been the internal engineering specifications and standards that the device's performance was measured against. This is not clinical ground truth.
8. The sample size for the training set
Not applicable. There is no mention of a training set as this is a physical medical device, not a machine learning algorithm.
9. How the ground truth for the training set was established
Not applicable, as there is no training set.
§ 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).