(28 days)
The Miethke proGAV Programmable Shunt System is intended to shunt cerebrospinal fluid (CSF) from the lateral ventricles of the brain into the peritoneum. Adjustments of the proGAV shunt can be verified by using the verification instrument but must be confirmed by radiograph (X-ray).
The proGAV is a "programmable" shunt that can be set for a range of pressures. The valve in the proGAV is a leaf spring and ball mechanism that is mechanically controlled by internal magnets. The outer case for the device is made of titanium. The shunt comes with a manual device to verify the pressure setting and another to set or re-set the pressure. These manual accessories are both for external use by the physician. Once verified using the instrument the setting must be confirmed with an X-ray. Various Miethke shunt system accessories such as shunt assistants, catheters, connectors, deflectors and reservoirs are also offered with the proGAV . The proposed modification is to the internal magnet.
Acceptance Criteria and Study for Miethke proGAV Shunt (K103003)
This 510(k) pertains to a modification of the Miethke proGAV Shunt, specifically to its internal magnet. The submission claims substantial equivalence to the previously cleared proGAV Shunt (K062009) and focuses on ensuring the modified device maintains the same safety and effectiveness.
1. Table of Acceptance Criteria and Reported Device Performance
The provided document does not explicitly present a table of numerical acceptance criteria or performance metrics for the proGAV shunt. Instead, it lists the types of tests conducted to demonstrate safety and effectiveness, particularly concerning MRI compatibility, which is a critical aspect for devices with internal magnets.
| Acceptance Criteria Category | Test Performed | Reported Device Performance (Implied) |
|---|---|---|
| MRI Safety - Image Artifacts | ASTM F2119: Evaluation of MR Image Artifacts | The device passed this test, implying that it does not produce unacceptable MR image artifacts that would hinder diagnostic imaging or compromise patient safety during MRI procedures. |
| MRI Safety - RF Induced Heating | ASTM F2182: Measurement of Radio Frequency Induced Heating During Magnetic Resonance Imaging | The device passed this test, indicating that it does not undergo significant or unsafe temperature increases when exposed to radiofrequency fields during MRI. This prevents the risk of thermal injury to the patient. |
| MRI Safety - Magnetically Induced Torque | ASTM F2213: Qualitative Measurement of Magnetically Induced Torque in the Magnetic Resonance Environment | The device passed this test, suggesting that it does not experience dangerous levels of torque when exposed to the strong static magnetic fields of an MRI scanner. This ensures the device remains in its intended location and does not cause internal damage. |
| MRI Safety - Magnetically Induced Displacement Force | ASTM F2052: Measurement of Magnetically Induced Displacement Force on the in the Magnetic Resonance Environment | The device passed this test, implying that it does not experience significant displacement forces that would cause it to move or migrate within the body when exposed to the magnetic fields of an MRI. This is crucial for avoiding internal injury or compromising the shunt's intended function. |
| Functional Equivalence | Not explicitly detailed in the performance data section | Implicitly, the modified internal magnet is assumed to maintain the same functional characteristics (e.g., pressure adjustment range, accuracy) as the predicate device (K062009). The statement "The materials, design, principle of operation and intended use is equivalent to the previously cleared proGAV Shunt" supports this. |
2. Sample Size Used for the Test Set and Data Provenance
The provided document does not specify the sample size for the mechanical/biophysical tests conducted (ASTM F2119, F2182, F2213, F2052). These are typically bench tests performed on a defined number of device units rather than human patient data.
The data provenance is retrospective in the sense that it relies on demonstrating equivalence to an already cleared device and likely leverages existing knowledge about its performance. The tests themselves are laboratory/bench studies and do not involve human or animal subjects in this specific submission. Therefore, country of origin of data is not applicable in the context of clinical data.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
Not applicable. The tests performed are objective, standardized engineering/biophysical tests (ASTM standards) that do not require expert consensus or qualitative interpretation to establish ground truth. The 'ground truth' for these tests is the physical measurement itself, compared against predetermined engineering specifications and safety thresholds outlined in the ASTM standards.
4. Adjudication Method for the Test Set
Not applicable. As noted above, these are objective physical tests, not clinical evaluations 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
Not applicable. This device is a medical implant (shunt), not an AI-powered diagnostic or assistive tool. Therefore, an MRMC study comparing human readers with AI assistance is not relevant or applicable to this submission.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Not applicable. This is a physical medical device, not a software algorithm.
7. The Type of Ground Truth Used
The ground truth for the performance data (MRI compatibility tests) is the physical measurements and observations derived from standardized ASTM test methods. These methods provide objective, quantifiable data that are compared against predefined safety limits and performance characteristics.
8. The Sample Size for the Training Set
Not applicable. This device does not involve a "training set" in the context of machine learning or AI algorithms. The "training" for this type of device development involves engineering design, material selection, and manufacturing processes, culminating in verification and validation testing.
9. How the Ground Truth for the Training Set Was Established
Not applicable, for the same reason as point 8. The "ground truth" during the development and manufacturing of such a device would be established through a rigorous quality management system, engineering specifications, design controls, and adherence to relevant standards, ensuring the device consistently meets its intended performance and safety requirements.
§ 882.5550 Central nervous system fluid shunt and components.
(a)
Identification. A central nervous system fluid shunt is a device or combination of devices used to divert fluid from the brain or other part of the central nervous system to an internal delivery site or an external receptacle for the purpose of relieving elevated intracranial pressure or fluid volume (e.g., due to hydrocephalus). Components of a central nervous system shunt include catheters, valved catheters, valves, connectors, and other accessory components intended to facilitate use of the shunt or evaluation of a patient with a shunt.(b)
Classification. Class II (performance standards).