Posted on Jan 13, 2010, 6 a.m.
Italian researchers suggest a new type of magnetic resonance imaging may help doctors to distinguish between the effects of normal aging and the preclinical stages of Alzheimer disease.
Diffusion tensor imaging, a type of Magnetic Resonance Imaging (MRI), detects the random movement of water through brain tissue at the microscopic level. Giovanni Carlesimo, from Tor Vergata University (Italy), and colleagues, used diffusion tensor imaging to scan the brains of 76 healthy individuals, ages 20 to 80 years. The researchers found that mean diffusivity, which can be useful to track pathologic changes in white and gray matter, in the hippocampus, rather than hippocampal volume, predicted performance on memory tests among healthy adults. The team concludes that: “High mean diffusivity values in the hippocampal formation of healthy elderly individuals predict memory decline, as reflected by performance on tests of declarative verbal and visual-spatial memory.”
Giovanni A. Carlesimo, Andrea Cherubini, Carlo Caltagirone, Gianfranco Spalletta. “Hippocampal mean diffusivity and memory in healthy elderly individuals. A cross-sectional study.” Neurology,
January 6, 2010; doi: doi:10.1212/WNL.0b013e3181cb3e39