The valve was received submerged in an unidentified liquid in a plastic container.A deformation of the outer housing of the valve was observed through the visual in specification.The prosa valve housing was measured to confirm the presence of the deformation.The housing deformation measured at -0.0710mm, outside the tolerance of -0.02 +-0.02mm.The permeability test showed that the valve had a blockage.The valve was tested and is not adjustable throughout the normal range.The braking functionality test has shown that the brake function operates as expected.However, due to inability of the valve to hold a set pressure, the breaking force was not able to be measured.To test the opening pressure, we use a miethke computer controlled testing apparatus which stimulates a cerebrospinal fluid flow.Because the valve is not permeable, the computer controlled test is not possible.We performed a visual inspection of the prosa valve.A deformation of the outer casing of the valve was observed through the visual inspection.The deformation was confirmed with a measurement of the pain paralleity.Next we performed a permeability and adjustability of the valve, as well as the brake functionality.The valve did not operates as expected.The test results indicates that the prosa has a blockage and is non-adjustable.We were also unable to test the opening pressure to investigate the claim of under drainage due to the non-permeability of the valve.We were unable to determine the required braking force due to the non-adjustability of the valve.Finally, we have dismantled the valve.Inside the prosa we have found a buildup of substance (likely protein).Based on our investigation, we confirm that the valve is non-adjustable, likely due to the deposits observed inside the valve.Furthermore, it is likely that the observed deformations of the housing could have negatively impacted the performance of the valve.The causes of the deformation of the prosa valve could not be determined through our investigation.However, it should be noted that outside pressure, for example by too much force from the prosa adjustment tool or by a fall or impact to the head of the patient, can compromise the integrity of the valve.We can exclude a defect at the time of release.The valve met all specifications of the final inspections.
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