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Visual inspection: during the investigation, scratches on the outer housing of the valves, but no significant deformations were determined.Permeability test: a permeability test has shown that both valves are permeable.During the permeability test bloody liquid was flushed out.Computer controlled test: to investigate the claim of under-drainage, the opening pressure is measured using a miethke computer controlled testing apparatus which simulates a cerebrospinal fluid flow.The valves are tested in both the horizontal as well as the vertical position.The result shows that the progav 2.0 operates within the accepted tolerances in the horizontal position.However, the m.Blue does not operate within the specified tolerances in the vertical position.An accelerated outflow of the m.Blue could be determined.Adjustment test: the valves were tested and both valves are adjustable in all pressure settings.Braking force and brake function test: the brake functionality test has shown that the brake function operates as expected and the braking force is within the given tolerance.Internal inspection: after dismantling of the valves, organic deposits were found in m.Blue.Results: based on our investigation results, we can detect an accelerated outflow at the m.Blue.The partially bloody deposits visible in the valve have led to the change in the flow rate.We were able to detect visible bloody deposits in the progav 2.0.The deposits did not affect the technical properties at the time of the investigation.In the control reservoir, we could not detect any functional deviations or other anomalies.The reservoir works within the specification.Deposits caused by natural substances in the body, such as protein, blood or tissue particles, are among the known and unavoidable risks and side effects of hydrocephalus therapy.Even small amounts of organic deposits can impair the integrity of the valve.When valves are opened, it is possible to see a large part of the interior.However, there are areas that cannot be examined visually.These areas may contain organic deposits that can impair the function.It is also possible that deposits are already flushed out when the valve is flushed on the test bench.We can exclude a defect at the time of release.The shunt system met all specifications of the final inspection when released from christoph miethke gmbh & co.Kg.No further regulatory actions are required from our point of view.
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