Neuroimaging Findings in the Evaluation of Dementia: A Review

Dementia is defined as a decline in mental abilities severe enough to interfere with normal everyday activities. It is a generic term that encompasses a wide spectrum of clinical signs and symptoms, and can be caused by various etiologies, which include neurodegenerative processes, infections, intracranial hemorrhages, hydrocephalus, vascular etiologies, and certain genetic mutations. An accurate diagnosis of the underlying etiology can be challenging and relies on correlating the clinical and neuroimaging findings, which often requires invasive procedures for a definitive diagnosis. Overlapping clinical symptoms in certain types of dementias can make it especially difficult to make the correct diagnosis; imaging plays a critical role in these cases. This article describes the characteristic neuroimaging findings seen in common and some less common causes of dementia. When considered in the appropriate clinical context, the high sensitivity and specificity of these imaging findings allow for an early and accurate noninvasive diagnosis of the specific type of dementia.

Learning Objective: Describe the salient neuroimaging findings that distinguish the different types of dementia discussed in the article.