Classification and Definition of Hydrocephalus: Origin, Controversy, and Assignment of the Terminology

Since hydrocephalus is not a single pathological disease, but a pathophysiological condition of disturbed dynamics of the cerebrospinal fluid (CSF) with or without underlying disease, its classification is often complex and confused. There are numerous classification categories, parameters, and criteria (Table 1). In each patient hydrocephalus can be given a classification, to which are added further individual qualifying parameters and variables, so that the full range of classified subtypes of hydrocephalus can be uncountable: congenital-fetal/progressive/high-pressure/non-communicating/idiopathic/macrocephalic/internal-triventricular hydrocephalus, etc.