(60 days)
The Axium™ Detachable Coil System is indicated for the endovascular embolization of intracranial aneurysms and other neurovascular abnormalities, such as arteriovenous malformations and arteriovenous fistulae. The Axium™ Detachable Coils are also indicated for arterial and venous embolizations in the peripheral vasculature.
The Axium™ Detachable Coil System consists of a platinum/tungsten embolization coil attached to a composite implant delivery pusher with a radiopaque positioning marker and a hand-held Axium™ I.D. (Instant Detacher) which, when activated, detaches the coil from the delivery pusher tip. The Axium™ I.D. (Instant Detacher) is sold separately.
This submission expands the size offerings of the Axium™ Detachable Coil (subject device) by adding thirty-five (35) new model numbers to the currently cleared Axium product portfolio (predicate device). These new model numbers are a line extension of the currently sold predicate device and range in size from 1mm diameter x 1cm length to 3.5mm diameter x 10cm length. All thirtv-five (35) new SKUs have a smaller primary wire diameter than the predicate device. This line extension includes six (6) coils having a 1mm diameter which is outside of the currently cleared Axium size range of 1.5mm diameter x 1cm length to 25mm diameter x 50cm length.
The second modification features a change to the Implant Delivery Pusher by replacing the PET material of the Positive Load Indicator (PLI) and Hypotube Break Indicator (BI) with a laser mark.
These modifications to the currently cleared predicate device were made solely to accommodate the new smaller implant coil size of the subject line extension. All other aspects of the subject device (materials of construction of the implant coil, principles of operation, packaging, labeling and indications for use) are identical to the predicate device.
This document describes a 510(k) submission for a medical device called the Axium™ Detachable Coil System. The submission is for a line extension of an already cleared device, introducing new coil sizes and a minor change to the implant delivery pusher.
Here's an analysis of the provided information regarding acceptance criteria and the study that proves the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance:
The document summarizes the bench tests performed. The acceptance criteria for each test are implicitly that "All devices met acceptance criteria." The device performance is reported as meeting these criteria.
| Test | Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|---|
| Visual and Dimensional Inspection (Coil, Sheath, Implant Delivery Pusher) | Dimensions (ID, OD, length) were measured, and key characteristics were inspected of the implant coil, sheath, and coupler tube, within specified tolerances. | All devices met acceptance criteria. |
| Softness and Conformability (Coil Deformation) | The first loop of the coil is advanced until it exits the sheath and is compressed to a deformation distance that is a percentage of the coil's loop OD. The peak force is recorded within an acceptable range for proper coil softness and conformability. | All devices met acceptance criteria. |
| Ease of Deliverability (Force Transfer, Friction Testing, Fatigue and Knotting) | Force Transfer: Peak delivery force measured through a representative tortuous anatomical model must be within acceptable limits. Friction Testing: The proximal end of the device is advanced until the distal force exceeds a specified value, and the force transfer must be calculated within acceptable limits. Fatigue and Knotting: The device is placed inside the microcatheter and advanced until the coil is deployed completely inside the aneurysm model, then retracted and the cycle repeated for a required number of cycles without evidence of fatigue or knotting upon inspection. | All devices met acceptance criteria. |
| Detachment (Coil Tensile – Polypropylene, Coil Tensile – Implant/Weld) | Coil Tensile – Polypropylene: The coil is stretched until the stretch resistant member breaks, and the peak force result is recorded and must be within an acceptable range. Coil Tensile – Implant/Weld: The primary wire of the coil is stretched until the coil-coil shell weld breaks, and the peak force result is recorded and must be within an acceptable range to ensure proper detachment and integrity. | All devices met acceptance criteria. |
| Labeling Verification | Text and format of drawings were visually compared to labeling and packaging product specifications and must match. | All devices met acceptance criteria. |
| Physician Usability Testing | The device was navigated through a tortuous benchtop model and deployed into a simulated silicone aneurysm to assess coil softness, conformability, ease of delivery, and biomechanical stability according to pre-defined criteria. | All test results met the acceptance criteria. |
| Adopted Tests (from predicate device): | ||
| Torque Response | The device's response to applied torque must be within acceptable limits to ensure steerability and control. | Passed (implied by adoption from cleared predicate) |
| Coil Tensile - Assembly | The tensile strength of the coil assembly (excluding specific weld/fiber breaks, which have individual tests) must meet predefined strength requirements. | Passed (implied by adoption from cleared predicate) |
| Pusher Dimensions | Dimensions of the implant delivery pusher must conform to specifications. | Passed (implied by adoption from cleared predicate) |
| Marker Radiopacity | The radiopacity of the marker on the device must be sufficient for clear visualization under fluoroscopy. | Passed (implied by adoption from cleared predicate) |
| Tip Buckling | The device tip must not buckle under specified forces or conditions. | Passed (implied by adoption from cleared predicate) |
| Detachment Zone Stiffness | The stiffness of the detachment zone must be within an acceptable range to ensure reliable detachment while maintaining appropriate flexibility. | Passed (implied by adoption from cleared predicate) |
| Kink Resistance | The device must resist kinking when navigated through tortuous paths or under simulated use conditions. | Passed (implied by adoption from cleared predicate) |
| Hypotube and Weld Tensile Strength | The tensile strength of the hypotube and its welds must meet specified requirements to prevent breakage during use. | Passed (implied by adoption from cleared predicate) |
| Pusher Elongation | The implant delivery pusher must not elongate beyond specified limits under typical forces encountered during use. | Passed (implied by adoption from cleared predicate) |
| MRI Compatibility | The device must be demonstrated to be safe for use in an MRI environment according to relevant standards. | Passed (implied by adoption from cleared predicate) |
| Sterilization, Biocompatibility, and Aging data (for the new SKUs) | Must demonstrate sterility, biocompatibility, and shelf-life equivalent to the predicate device due to no changes in manufacturing process, packaging, or materials of construction for the implant coil, and reduced mass. For the laser marks, physicochemical and cytotoxicity testing confirmed no impact on safety. | Passed (implied by adoption from cleared predicate, and specific testing for laser marks) |
2. Sample Size Used for the Test Set and Data Provenance:
- Test Set (Bench Testing): The document does not explicitly state the sample sizes for each specific bench test (e.g., "n=X coils"). It states "All devices met acceptance criteria," suggesting that multiple units of each new SKU were tested. The total number of new SKUs is 35.
- Data Provenance: The data is based on bench testing performed by the manufacturer (Micro Therapeutics, Inc. d/b/a ev3 Neurovascular). It is prospective in the sense that the tests were conducted specifically for this 510(k) submission to demonstrate substantial equivalence of the new offerings. There is no mention of geographical origin for the bench testing data; it's assumed to be from the manufacturer's testing facilities.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:
- This submission relies primarily on engineering and performance bench testing, not clinical data or expert visual assessment in the traditional sense of diagnostic imaging.
- For the "Physician Usability Testing," the document states, "The device was navigated through a tortuous benchtop model and deployed into a simulated silicone aneurysm in order to assess coil softness, conformability, ease of delivery and biomechanical stability." It doesn't specify the number or qualifications of physicians who performed or assessed this usability testing. Given it's a benchtop test, it likely involved internal engineering or R&D personnel with relevant medical device experience, possibly overseen or advised by clinicians. It is not mentioned as a formal clinical study with expert ground truth establishment.
4. Adjudication Method for the Test Set:
- Not applicable in the typical sense of diagnostic performance or clinical outcomes. The bench tests have defined parameters and measurements, with results either meeting or not meeting the acceptance criteria. The "Physician Usability Testing" outcome is reported as "All test results met the acceptance criteria," indicating a singular decision based on the assessment criteria.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- No, an MRMC comparative effectiveness study was not done. The document explicitly states: "No clinical study was performed as there is no change to the indications for use or the fundamental scientific technology for the new model numbers."
6. Standalone (Algorithm Only) Performance Study:
- No, this is a physical medical device (embolization coils), not an AI or software algorithm. Therefore, a standalone algorithm performance study is not applicable.
7. Type of Ground Truth Used:
- Engineering Specifications and Performance Standards: For the bench testing, the "ground truth" is defined by established engineering specifications, performance requirements, and industry standards for medical devices of this type. These standards relate to dimensions, mechanical properties (e.g., force, tensile strength, resistance to deformation), and functional performance (e.g., detachment, deliverability).
- Predicate Device Data: A significant portion of the "ground truth" or basis for comparison comes from the predicate Axium™ Detachable Coil System. The new devices are deemed substantially equivalent by demonstrating similar performance to the already cleared predicate device, and in many cases, adopting the predicate's testing data for aspects where no change occurred or where the change (e.g., smaller size, laser mark) was proven not to negatively impact performance.
8. Sample Size for the Training Set:
- Not applicable. This device does not use machine learning or AI algorithms that would require a 'training set.'
9. How the Ground Truth for the Training Set Was Established:
- Not applicable, as there is no training set for this type of device submission.
§ 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).