**1. Introduction**

First described by Hakim and Adams [1] in 1965, normal pressure hydrocephalus (NPH) is a potentially reversible cause of dementia. It is a communicating hydrocephalus, which occurs as a result of impaired re‐absorption of cerebrospinal fluid (CSF). This can be caused by a number of conditions including meningitis, trauma and subarachnoid haemorrhage. Howev‐ er, in a large number of cases, it is idiopathic (INPH). INPH is characterised clinically by the triad of gait disturbance, cognitive decline and urinary incontinence. Ventriculomegaly is observed on magnetic resonance imaging (MRI) or computed tomography (CT). However, the symptoms of INPH are non‐specific and can occur in other conditions. Moreover, the classic triad is not always present. Varying combinations and degrees of each element of the triad are encountered in different patients and depending on the stage of the condition. INPH has an

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

insidious onset and progresses gradually. Shunt surgery results in a positive response in as many as 84% in a European multicentre study [2]. Although the treatment is surgical, neurological input is important for the diagnosis and identification of suitable shunt candi‐ dates. In some countries, hydrocephalus is a purely surgical condition. However, like several authors, we believe that a multidisciplinary approach is essential for the optimal manage‐ ment of these patients. In our neuroscience centre, the management of INPH involves the neurologists, neurosurgeons and physiotherapists.

#### **2. Methods**

This review was prompted by the large number of publications on INPH. We searched the databases of Medline, Embase and the Cochrane Library for articles relating to INPH up to February 2016. We included review articles and research studies according to their relevance.
