[Experience with shunting operation using a pressure-adjustable valve].

Ten patients, 8 with hydrocephalus and 2 with a subdural fluid collection, were operated using a pressure-adjustable shunt system (SOPHY). The valve-pressure of this shunt device can be adjusted percutaneously by means of a specially designed magnet. In the postoperative course, the valve-pressure was reset in 7 patients. In four patients, valve-resetting was necessitated because of inappropriate valve pressure. In the others, resetting was performed in order to confirm shunt-independence. Especially, in the case with disproportional large communicating fourth ventricle, we could adjust valve-pressure three times without surgical procedure. Although the number of cases in this study is small, this shunt device seems to be efficient in treating both the disorders of CSF circulation and subdural fluid collections. However, this device must make an artifact in the MR imaging because of its small pieces of magnet. So we recommend the device is placed on the chest if the follow-up MR imaging is necessitated. And as it is larger than other kinds of shunt devices, it might cause the necrosis of the skin on the device, especially in the newborn. But we have never seen the necrotic change of the skin since our first operation using it.