Continuous intracranial pressure recording in adult hydrocephalus.

An implantable intracranial pressure sensor was used to diagnose and monitor the treatment of 17 adults with hydrocephalus. The intracranial pressure sensor was implanted before shunting in most cases and patients were studied in a sleep laboratory for two nights during which the intracranial pressure was measured throughout the night. Cases included five examples of acute hydrocephalus secondary to tumor, subarachnoid hemorrhage or meningitis, and 12 cases of long standing hydrocephalus diagnosed as normal pressure hydrocephalus, aque-ductal stenosis, or hydrocephalus ex vacuo. Continuous intracranial pressure monitoring was a valuable adjunct in the diagnosis and management of these patients. Continuous overnight recordings of intracranial pressure were helpful in determining compromised cerebral compliance by observing the shape and the amplitude of the intracranial pressure waves during desynchronized sleep. A second method for checking cerebral compliance is also described.