Alzheimer’s disease
Structural MRI studies have demonstrated that MTL volumes predict progression to AD from mild states of memory impairment and correlate with impaired memory performance in AD patients, supporting the contention that M TL volumetric measures are both clinically and biologically relevant.
Abstract
The application of neuroimaging technology to study Alzheimer’s disease (AD) has been steadily increasing over the last two decades. To date, the majority of neuroimaging contributions to understanding the pathophysiology and clinical course of AD have utilized structural magnetic resonance imaging (MRI) and positron emission tomography (PET). Influenced by pathological data, which reveal that the earliest disease manifestations are in medial temporal lobe (MTL) structures such as the hippocampus and entorhinal cortex (Braak and Braak 1991), structural MRI studies have largely focused on volumetric measures of the MTL. Starting in the early 1990s, MTL volumes were shown to distinguish agematched normal controls and AD patients, including those with very mild forms of the disease where the diagnosis of dementia was not yet conclusive (Jack et al. 1992, 1997). Further studies using quantitative volumetric measures have now demonstrated that MTL volumes predict progression to AD from mild states of memory impairment (de Leon et al. 1993; Jack et al. 2000; Dickerson et al. 2001; Mungas et al. 2002) and correlate with impaired memory performance in AD patients (de Toledo-Morrell et al. 2000; Petersen et al. 2000), thus supporting the contention that MTL volumetric measures are both clinically and biologically relevant. The application of structural MRI has continued to advance as other measures have complemented the volumetric studies. For example, the use