|
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 within the accepted tolerances in the horizontal position.However, the m.Blue does not operate within the specified tolerances in both positions.A slower outflow of 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, bloody organic deposits were found in both valves.Results: based on our investigation results, we can determine a slower outflow of the m.Blue.The determined organic deposits can be named as the cause for the functional deviation.Furthermore, we can determine organic deposits in the progav 2.0.The deposits had no effect to the technical properties at the time of the investigation.Organic matter in the cerebrospinal fluid can influence the function temporarily and are known inherent side effects in hydrocephalus therapy.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.
|