A comparison of neuroimaging modalities for diagnosing dementia

Advances in neuroimaging have permitted knowledge of brain structures and physiology that were unknown 20 years ago and are playing an increasingly important role in the diagnosis of dementia. This article provides information on the types of brain scans, usual indications, risks, costs, and preparation of patients undergoing neuroimaging for the diagnosis of dementia. Each of the major imaging modalities is discussed from the perspective of what it uniquely offers to the diagnostic process. In general, the information gained from anatomic imaging complements that obtained from functional studies. In early stages of dementia, anatomic scans may appear normal while significant abnormalities are evident in functional images. This review familiarizes clinicians with these major developments to prepare them to educate and communicate with patients and their families.