[Progress in diagnosis of and therapy for idiopathic normal-pressure hydrocephalus--Classical view of cerebrospinal production, absorption and bulk flow and its criticism].

It has long been considered that cerebrospinal fluid (CSF) flows from choroid plexus through the aqueduct, and finally is absorbed from the arachnoid villi near the superior sagittal to mix the venous blood. Recently, this CSF bulk flow theory is challenged by new ideas, one of which claims that brain capillaries are a major site for production and absorption of CSF. This new idea gives revision of previous understandings of CSF production, absorption and dynamics. However, revision of previous works may provide a great progress in CSF research.