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Visual inspection: during the investigation, no significant deformations or damage of the valves were determined.Permeability test: a permeability test has shown that the paedigav 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 valve is tested in both the horizontal as well as the vertical positions.The results show that the valve operates within the accepted tolerance in the vertical but not in the horizontal position.An accelerated/reduced outflow of paedigav could be determined.Internal inspection: after dismantling of the valve, visible deposits were found in the paedigav.Results: based on our test results, we can determine a reduced outflow at the valve.The deposits visible in the valve may have led to the change in flow rate.Deposits caused by substances naturally present in the patient's body, such as organic matter, blood or tissue particles, are among the known and unavoidable risks and side effects of hydrocephalus therapy.Even small amounts of organic material can affect the integrity of the valve.The examination of the return has been completed with the drafting of this report.We would also like to point out that the condition of the product may be affected by the period between the explantation date and the release of the product.Long storage times may additionally affect the investigation results.We can exclude a defect at the time of release.The valve 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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