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Investigation: visual inspection: the following observations were made during the visual inspection: -reservoir twisted to the rest of the shunt system -deposits on the reservoir -small hole in the catheter between reservoir and progav® 2.0 permeability test: the test showed that the progav 2.0 shunt system is permeable.Computer control test: the computer control test showed the opening pressure of the progav 2.0, at a reference flow rate of 20 ml/h in a horizontal position of the valve, to be 16.89 cmh2o.This is not within the specified tolerance of 0 ± 3 cmh2o.An applied pressure of 0 cmh2o, with the device in the horizontal position is expected to have a resultant pressure of 0 ± 3 cmh2o.According to our results, we can detect a presence of a slowed outflow.Additionally, the shuntassistant was tested according to standard procedure in the vertical position of the valve.At a fixed opening pressure of 20 cmh2o in the vertical position, a pressure of 20 +4/-2 cmh2o is expected.The results indicated that at a reference flow of 20 ml/h in the vertical position, the shuntassistant had a pressure of 18.81 cmh2o.This is within the specified tolerance of 20 +4/-2 cmh2o.Adjustability test: the progav 2.0 was found to be adjustable to all pressure settings.The shuntassistant is a fixed pressure valve, therefore the adjustability test is inapplicable.Braking force and brake function test: the braking force of the progav 2.0 was within the specified tolerance and the brake function operated as expected.Internal inspection of product: in order to verify whether the investigated shunt system was compromised by the known risks of hydrocephalus therapy, e.G.By a build-up of natural substances (protein, blood, or tissue particles) in the cerebrospinal fluid, the valves were finally opened with a special tool.After dismantling of the valves, deposits were found in both valves.Results: for the sake of thoroughness and transparency, we would like to point out that a permeability test was already carried out after the revision at the hospital.Based on our investigation results, we have determined that there was a slower outflow in the progav 2.0 valve at the time of our investigation.Detected deposits were the cause of the slower outflow.Existing deposits in the csf can temporarily impair the function of the valve and is described as concomitant symptoms 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.From our point of view, no further regulatory actions are required.
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