[Determination of flow capacity in valves for ventriculo-auricular drainage]

In model experiments both of the customary valves for ventriculo-auricular draining (Spitz-Holter valve and Pudenz-Heyer valve) are tried. Aperient pressures as well as flow amounts in relation to given pressure values are determined and plotted. In long-term examination for 1 year both kinds of valves exhibit irregular flow capacities, that have no significant tendency in the Spitz-Holter valve, whereas the flow through the Pudenz-Heyer valve is more and more diminished during the course of time.