Literal translation, “water on the brain.”  An excessive buildup of cerebrospinal fluid which results in an unusual widening of spaces in the brain called ventricles.  It can be either present at birth, or happen later in life. Hydrocephalus is a “space occupying mass” that increases intracranial pressure (Intracranial Hypertension), which can lead to a vast array of other comorbid conditions including an Acquired Chiari Malformation.