Study: PET scans are instrumental in early Alzheimer's disease diagnosis
Positron emission tomography (PET) is gaining more evidence that the imaging modality is an accurate method of diagnosing Alzheimer's disease (AD), particularly in its early stages.

The latest study comes from the University of Florence (Italy) and is published in the March issue of The Journal of Nuclear Medicine.

The study offers a new PET technique. Researchers report that AD-related processes leading to altered brain connections between the entorhinal cortex (EC) and both hemispheres of the brain can be clearly identified with 18F-FDG (fluorodeoxyglucose) PET. The EC is a small area located deep in the brain that plays a central role in memory functions, and is an early site for neuronal damage resulting in memory impairment in AD.

"This study shows that most of these connections between the hemispheres are destroyed at a very early stage of AD," said lead author Lisa Mosconi, MD, of the Department of Clinical Pathophysiology Nuclear Medicine Unit at the University of Florence. "For example, when brain metabolism is reduced in the right EC, a parallel reduction can be found in the right neocortical areas. Such a pattern of coupled metabolic reductions between the deep and surface brain may make PET even more accurate at differentiating AD from other forms of dementia."

Early diagnosis of AD has become critical now that drugs are available that may help slow the otherwise unremitting course of the disease. An accurate diagnosis also is critical to determine early therapy, since some promising treatments have been shown to exacerbate other forms of dementia.