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Visual inspection: during the visual inspection a deformation of the outer housing of the progav valve could be determined.The measurement of the plane parallelism could confirm that with a value of -0,056 mm - outside tolerance (0 ± 0.02 mm).Permeability test: a permeability test has shown that the valve is permeable.Computer controlled test: to investigate the claim of blockage, the opening pressure is measured using a miethke computer controlled testing apparatus which simulates a cerebrospinal fluid flow.The valve is tested in the horizontal position.The results show that the valve operates within the accepted tolerances in the horizontal position.Adjustment test: the progav was tested and is adjustable to all specified pressures.Braking force and brake function test: the brake functionality test has shown that the brake function is fully operational and the braking force is within the given tolerances.Internal inspection: after dismantling of the valve, no deposits were found in progav.To make the proteins / deposits in the valve more visible, they were colored using a staining solution.Result: in advance, we would like to point out that the product sent in was not submerged in liquid at the time of delivery.The testing of dry valves is only of limited value.The product properties can be influenced by dry residues of cerebrospinal fluid or blood.Despite this, we have examined the valve.Based on our investigation results, we can detect a slight deformation on the housing of the valve but no functional deviations or other abnormalities on the product.How the aforementioned functional impairment came about is not clear to us at the time of the investigation.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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