(92 days)
The M.blue Adjustable Shunt System is used for cerebrospinal fluid (CSF) shunting.
M.blue is an adjustable valve that combines an adjustable gravitational unit and a fixed differential pressure unit. The M.blue valve can be set for a range of pressures and is offered in four pressure level settings. The M.blue valve is comprised of a titanium housing enclosed by a thin titanium membrane with a curved wave profile design. The gravitational unit of the M.blue valve contains a tantalum weight, leaf spring and ball mechanically controlled by internal magnets. The differential pressure unit (ball-in-cone) of the M.blue valve contains a sapphire ball and titanium spring.
Manual devices are available to locate, verify the pressure setting and to set or change the pressure pre and postoperatively. These manual accessories are for external use by the Healthcare provider.
The M.blue valve will be distributed by itself or in combination with the proGAV 2.0 valve. The M.blue valve includes the same legally marketed accessories that are available with the Miethke Shunt Systems.
The provided document describes the K192266 submission for the M.blue Adjustable Shunt System. This document focuses on the device's performance criteria and its substantial equivalence to a predicate device, rather than the performance of an AI/ML device or a medical imaging device. Therefore, many of the requested categories for AI/ML study descriptions are not applicable.
Here's an analysis based on the available information:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for the M.blue Adjustable Shunt System are based on various performance tests demonstrating its safety and efficacy, often by showing it performs substantially equivalent to the predicate device.
| Test | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Radiopacity | Shunt identifiable by radiographic pressure coding and flow direction via X-ray examination. | Samples passed the acceptance criteria and therefore substantially equivalent to the predicate device. |
| Resistance to Leakage | No leakage with a differential pressure of 100 cm water column within 5 min when 100 cm of air applied while submerged in water. | Samples passed the acceptance criteria and therefore substantially equivalent to the predicate device. |
| Control of the Implanted Shunt | Functionality of the shunt and the method of control. | Functional characteristics and control procedure are cited in the Instructions of Use and therefore substantially equivalent to the predicate device. |
| Pressure-Flow | Measured pressure must remain within manufacturer's declaration for flow range of 5 to 50 ml/h. | Samples passed the acceptance criteria and therefore substantially equivalent to the predicate device. |
| Overpressure | Device function and integrity must withstand a positive pressure of 1 meter water column applied to the open shunt. | Samples passed the acceptance criteria and therefore substantially equivalent to the predicate device. |
| Dynamic Break Strength | Withstand 100,000 cycles with a frequency of 1 Hz ±0.2, tension applied in flow direction leading to 10% elongation or a maximum force of 5 N. | Samples passed the acceptance criteria and therefore substantially equivalent to the predicate device. |
| Bursting Pressure | Withstand a positive pressure of 2 meters water column inside the device without any change within ±10% tolerance (within 2 hours after burst pressure application). | Samples passed the acceptance criteria and therefore substantially equivalent to the predicate device. |
| Reflux performance | Maximum flow of 0.04 ml/min allowed to be drained back when subjected to 500 mm of water column against flow direction. | Samples passed the acceptance criteria and therefore substantially equivalent to the predicate device. |
| Long Term Stability | Maintain performance over 28 days immersed in distilled water at 36°C ±5, pumping distilled water at 20 ml/h, with simulated patient position (14 days horizontal, 14 days vertical). | Samples passed the acceptance criteria and therefore substantially equivalent to the predicate device. |
| Influence of the changed posture of the patient on the valve performance | Valve characteristics should explicitly depend on patient posture and be cited in the Instructions for Use. | The performance characteristics are cited in the Instructions for Use and therefore substantially equivalent to the predicate device. |
| Accuracy of the M.blue plus Compass | Equivalence between radiographic verification method and non-invasive method. | Samples passed the acceptance criteria and therefore substantially equivalent to the predicate device. |
| Effects of Exposure to MRI conditions | No effect on valve function and adjustability after MRI exposure. | Samples passed the acceptance criteria and therefore substantially equivalent to the predicate device. |
| Brake safety test evaluation | Active-Lock mechanism protects against inadvertent re-adjustment by external magnetic fields. | There was no change in pressure setting and therefore substantially equivalent to the predicate device. |
| MRI safety testing | Meet standards for image artifacts (ASTM F2119), RF-induced heating (ASTM F2182), magnetically induced torque (ASTM F2213), and magnetically induced displacement force (ASTM E2052). | The results demonstrate that the device is MR Conditional in 3-Tesla Magnetic Resonance Imaging (MRI) systems according to ASTM F 2503 and is substantially equivalent to the predicate device. |
| Biocompatibility (Cytotoxicity) | Cell culture treated with test sample exhibited no leachable substances in cytotoxic concentrations / no substances with cytotoxic potential released from the test item for the M.blue plus with Control reservoir and Peritoneal catheter, M.blue plus Compass scale ring, and M. blue Checkmate. | Non-Cytotoxic (for all components tested). |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state numerical sample sizes for each test listed. It generally refers to "samples" passing the acceptance criteria. The data provenance (country of origin, retrospective/prospective) is not mentioned, but these are likely laboratory or bench tests conducted by the manufacturer.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
Not applicable. This is a device performance and biocompatibility study, not an AI/ML study requiring expert ground truth for image interpretation or diagnosis. The "ground truth" here is objective physical or chemical measurement against established standards.
4. Adjudication Method for the Test Set
Not applicable. There's no subjective assessment requiring adjudication in these device performance tests.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No, an MRMC comparative effectiveness study was not done. This device is a medical implant, not an AI-assisted diagnostic tool.
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 an algorithm. The performance tests are for the physical device itself.
7. The Type of Ground Truth Used
The ground truth used for these tests are:
- Established engineering standards and physical properties: e.g., pressure-flow characteristics, mechanical strength, resistance to leakage, bursting pressure, radiopacity.
- Biological and chemical standards: e.g., cytotoxicity assays against ISO standards (ISO-10993).
- MRI safety standards: as per ASTM guidelines.
- Manufacturer's declarations: for certain performance characteristics mentioned in the Instructions for Use.
8. The Sample Size for the Training Set
Not applicable. There is no "training set" as this is not an AI/ML product.
9. How the Ground Truth for the Training Set Was Established
Not applicable. There is no "training set."
Summary of Device and Study:
The K192266 submission describes the M.blue Adjustable Shunt System, a medical device for cerebrospinal fluid shunting. The core of the submission is to demonstrate its substantial equivalence to a legally marketed predicate device (Aesculap Miethke proSA Adjustable Shunt System K161853) and a reference device (Miethke Shunt System miniNAV Valve K110206).
The acceptance criteria are based on various physical and biological performance tests, as detailed in the table above. These tests cover aspects like radiopacity, resistance to leakage, pressure-flow performance, mechanical integrity (dynamic break strength, bursting pressure), long-term stability, and MRI compatibility. The device's components were also subjected to biocompatibility testing, specifically cytotoxicity, demonstrating the absence of cytotoxic potential.
The studies conducted are primarily bench testing (in vitro) and biocompatibility assessments. The document states that "All samples met predefined acceptance criteria and the proposed devices passed design verification test activities," concluding that the device "performs as intended and is substantially equivalent to the predicate device." The "performance data is provided in support of the substantial equivalence determination." This implies that the 'study' is a series of verification and validation tests aligned with relevant standards (e.g., EN ISO 7197:2009 for shunt safety and performance, and ISO-10993 for biocompatibility).
§ 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).