ABSTRACT
Although the diagnosis of dementia remains primarily clinically based, the past decade has yielded
important advances in adjunctive tests, particularly in the use of neuroimaging. Until recently,
neuroimaging was primarily used to exclude causes of dementia other than Alzheimer’s disease
(AD), such as cerebrovascular disease, and more rarely, tumor, subdural hematoma or normal
pressure hydrocephalus. Several neuroimaging techniques, however, have now shown promise in
making a more accurate, positive diagnosis of AD. This chapter will focus on functional
neuroimaging. Functional imaging techniques, particularly positron emission tomography (PET)
and single-photon emission computed tomography (SPECT), have now been shown to improve
diagnostic accuracy in patients with AD. Recently, functional neuroimaging techniques have also
been used to predict subsequent diagnosis of AD prior to the onset of clinical dementia. Early,
accurate diagnosis of dementia will become increasingly important over the next decade, as
potential disease modifying therapies for AD become available.
