What Radiologists Should Know About Normal Pressure Hydrocephalus

Abstract

Background Normal pressure hydrocephalus is a disease in elderly patients and one of the most common causes of treatable dementia. It occurs frequently with microangiopathy and Alzheimer’s disease, so that differential diagnosis plays an important role. This is crucially determined by imaging findings. Therapy consists of cerebrospinal fluid drainage through a shunt, which should be performed as early as possible to improve the chances of success.

Method This report is based on a summary of the relevant literature that has been reviewed in PubMed with reference to epidemiology, symptoms, pathophysiology, diagnostics, and therapy. The results were supplemented by the joint guidelines of the German Society of Neurology and the German Society of Neurosurgery.

Results and Conclusion The understanding of the pathophysiologic changes leading to normal pressure hydrocephalus has expanded significantly in recent years to include concepts explaining relevant comorbidities. Diagnosis is based on radiological and clinical indicators, although accurate differentiation with respect to comorbidities is not always possible. A high response rate to treatment can be achieved by good patient selection. Positive prognostic markers for therapeutic success include Disproportionately Enlarged Subarachnoid Space Hydrocephalus (DESH), short disease duration, predominant gait disturbance, and few comorbidities.

Key Points: 

• Normal pressure hydrocephalus mainly affects patients older than 65 years of age with high comorbidity rate for microangiopathy and Alzheimer’s disease

• Radiologic findings play an important role in the diagnosis and follow-up after shunting

• The earlier a shunt is placed, the better the outcome

Citation Format

• Illies T, Eckert B, Kehler U. What Radiologists Should Know About Normal Pressure Hydrocephalus. Fortschr Röntgenstr 2021; 193: 1197 – 1206

Key words

normal pressure hydrocephalus - gait disorder - shunt - Alzheimer’s - microangiopathy

Publication History

Received: 31 August 2020

Accepted: 15 February 2021

Article published online:
16 September 2021

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