PROPOSED GUIDELINES FOR THE ASSESSMENT AND MANAGEMENT OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS IN THE UNITED KINGDOM

Normal pressure hydrocephalus is a potentially treatable disorder of progressive gait decline usually associated with variable degrees of cognitive impairment. It is considered to be predominantly a disorder of gait, although urinary incontinence may be a feature. It still remains a challenging condition to diagnose and treat. There appears to be a lack of clarity with regards to diagnostic criteria and investigation. It is our aim to produce guidelines on diagnosis, investigation and management that do not rely on complex investigations and could be used in most centres. To this end we have performed an extensive literature review focussing on clinical features, radiological diagnostic features and optimum use of the large volume CSF tap test. We feel that a national database would greatly facilitate further research into this disorder and would help to better characterise the clinical and radiological features that predict shunt responsiveness. We propose an assessment framework based on published evidence that takes into account clinical, brain imaging and CSF tap test parameters that can be used as a basis for referral for shunt or more invasive investigation.The framework can also be used to collect data for a national database for retrospective analysis of the outcome of shunting and for further research.