Abstract
A new type of valve system for surgical treatment of hydrocephalus has been designed and developed. Results obtained from basic experiments by a scale-up model valve are summarized as follows.
1. Regarding the pressure control of the valve, the opening action of the valve occurs at the critical pressure difference, the flow through the valve begins at the pressure more than this critical one. The increase of the pressure difference along with increase of the flow is comparatively small even of large flow.
2. The prevention of counter flow is almost satisfactory with this valve. 3. With this valve, the cerebrospinal fluid pressure is easily controlled and hence, the valve may be applied to all patients with the abnormal cerebrospinal fluid pressure.
4. A significant advantage of this valve is the existence of the popping pressure, compared with other resistance-type valves.
