Normal pressure hydrocephalus (NPH), also called malresorptive hydrocephalus, is a form of communicating hydrocephalus in which excess cerebrospinal fluid (CSF) builds up in the ventricles, leading to normal or slightly elevated cerebrospinal fluid pressure. The fluid build-up causes the ventricles to enlarge and the pressure inside the head to increase, compressing surrounding brain tissue and leading to neurological complications. Although the cause of idiopathic (also referred to as primary) NPH remains unclear, it has been associated with various co-morbidities including hypertension, diabetes mellitus, Alzheimer's disease, and hyperlipidemia. The disease presents in a classic triad of symptoms, which are memory impairment, urinary frequency, and balance problems/gait deviations (note: use of this triad as the diagnostic method is obsolete; the triad symptoms appear at a relatively late stage, and each of the three can be caused by a number of other conditions). The disease was first described by Salomón Hakim and Raymond Adams in 1965. - Source: Wikipedia
