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It is now understood that asymptomatic communicating hydrocephalus can develop in many healthy older people, and that over time this can develop into a symptomatic state that sometimes responds to CSF shunting, but to a variable extent. This review looks at the historical background of NPH, the use of predictive tests, the current state of clinical evidence for the diagnosis and treatment of idiopathic NPH and the possible underlying causes, to provide a contemporary practical guide for assessing patients with the radiological features of idiopathic NPH.<\/jats:p>","DOI":"10.1136\/pn-2021-003291","type":"journal-article","created":{"date-parts":[[2022,9,26]],"date-time":"2022-09-26T13:22:32Z","timestamp":1664198552000},"page":"15-22","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":42,"title":["Idiopathic normal pressure hydrocephalus: historical context and a contemporary guide"],"prefix":"10.1136","volume":"23","author":[{"given":"Christopher","family":"Carswell","sequence":"first","affiliation":[{"name":"Imperial College Healthcare NHS Trust, London, UK"},{"name":"Department of Brain Sciences, Imperial College London, London, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2022,9,26]]},"reference":[{"key":"2025090410342102000_23.1.15.1","doi-asserted-by":"publisher","DOI":"10.1016\/0022-510X(65)90016-X"},{"key":"2025090410342102000_23.1.15.2","first-page":"28","article-title":"A technique for pneumo-encephalography","volume":"43","author":"Hepburn","year":"1940","journal-title":"Can Med Assoc J"},{"key":"2025090410342102000_23.1.15.3","doi-asserted-by":"publisher","DOI":"10.1056\/NEJM196507152730301"},{"key":"2025090410342102000_23.1.15.4","doi-asserted-by":"crossref","first-page":"316","DOI":"10.1093\/neurosurgery\/24.CN_suppl_1.316","article-title":"Occult hydrocephalus: results of shunting correlated with diagnostic tests","volume":"24","author":"Laws","year":"1977","journal-title":"Clin Neurosurg"},{"key":"2025090410342102000_23.1.15.5","doi-asserted-by":"publisher","DOI":"10.3171\/jns.1969.31.3.0279"},{"key":"2025090410342102000_23.1.15.6","doi-asserted-by":"crossref","first-page":"609","DOI":"10.1056\/NEJM197009172831201","article-title":"Diagnosis of normal-pressure hydrocephalus","volume":"283","author":"Benson","year":"1970","journal-title":"N Engl J Med"},{"key":"2025090410342102000_23.1.15.7","doi-asserted-by":"crossref","first-page":"1014","DOI":"10.1016\/S0140-6736(67)90288-7","article-title":"Isotope encephalography in the diagnosis of dementia due to communicating hydrocephalus","volume":"2","author":"Bannister","year":"1967","journal-title":"Lancet Lond Engl"},{"key":"2025090410342102000_23.1.15.8","doi-asserted-by":"publisher","DOI":"10.1001\/jama.1976.03260310024015"},{"key":"2025090410342102000_23.1.15.9","doi-asserted-by":"publisher","DOI":"10.1001\/jama.1973.03220400024005"},{"key":"2025090410342102000_23.1.15.10","doi-asserted-by":"publisher","DOI":"10.3171\/jns.1980.52.3.0371"},{"key":"2025090410342102000_23.1.15.11","doi-asserted-by":"publisher","DOI":"10.1136\/jnnp.40.4.336"},{"key":"2025090410342102000_23.1.15.12","doi-asserted-by":"publisher","DOI":"10.1136\/jnnp.36.1.146"},{"key":"2025090410342102000_23.1.15.13","doi-asserted-by":"crossref","first-page":"501","DOI":"10.1212\/WNL.26.6.501","article-title":"Computerized axial transverse tomography in normal pressure hydrocephalus","volume":"26","author":"Jacobs","year":"1976","journal-title":"Neurology"},{"key":"2025090410342102000_23.1.15.14","doi-asserted-by":"publisher","DOI":"10.1136\/jnnp.40.8.736"},{"key":"2025090410342102000_23.1.15.15","doi-asserted-by":"crossref","first-page":"534","DOI":"10.1212\/WNL.20.6.534","article-title":"A simple constant-infusion manometric test for measurement of CSF absorption. 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