A newly designed flow-regulating device in shunt therapy of hydrocephalus.

A new flow-regulating device for shunting in hydrocephalus was designed to limit an excess flow by a pressure-head between the cerebral ventricle and the abdominal cavity in a standing position. The device has two diaphragm valves connected to each other by two lines: one is a shunting line to transfer cerebrospinal fluid and the other is a control line filled with a control fluid with a higher density than cerebrospinal fluid. The performance of the model device with a natural rubber sheet diaphragm was tested in a mock system, using glycerol for the control fluid and water for the transfer fluid in vitro. Results show that device decreases the excess flow when the pressure-head between two valves exceeds 35 cm.