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Visual inspection: during the investigation, no significant deformations or damages of the valves were determined.Permeability test a permeability test has shown that both valves are permeable.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 not within the accepted tolerances in the horizontal position.However, the m.Blue operates within the specified tolerances in the vertical position.An accelerated outflow of progav 2.0 could be determined.Adjustment test: the valves were tested and the m.Blue is adjustable, but the progav 2.0 is not adjustable to all pressure settings.Braking force and brake function test: the brake functionality test at the m.Blue has shown that the brake function operates as expected and the braking force is within the given tolerance.The brake functionality test at the pro gav 2.0 has shown the brake function operates as expected.However, the braking force cannot be measured due to the non-adjustability of the valve.Internal inspection: after dismantling of the valves, organic deposits were found in both valves.Results: based on our investigation results, we can determine accelerated outflow and non-adjustability on the progav 2.0.The deposits visible in the valve have led to functional impairment.Furthermore, we can see visible deposits in the m.Blue.The deposits did not affect the technical properties at the time of testing.Deposits caused by natural substances found 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.The investigation of the return shipment is complete with the preparation of this report.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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