Title:Evolution of Global and Local Grey Matter Atrophy on Serial MRI Scans During the Progression from MCI to AD
VOLUME: 9 ISSUE: 4
Author(s): Gabriela Spulber, Eini Niskanen, Stuart MacDonald, Miia Kivipelto, Daniel Ferreira Padilla, Valtteri Julkunen, Merja Hallikainen, Ritva Vanninen, Lars-Olof Wahlund and Hilkka Soininen
Affiliation:University of Eastern Finland, Kuopio Campus, Institute of Clinical Medicine/Neurology, P.O.Box 1627, FI-70211 Kuopio; Finland
Keywords:Alzheimer's disease, longitudinal voxel based morphometry mild cognitive impairment, MRI
Abstract:Mild cognitive impairment (MCI) often represents a prodromal form of dementia, conferring a significantly
higher risk of converting to probable Alzheimer's disease (AD). The aim of this study is to characterise the differences of
grey matter (GM) distribution and dynamics between progressive and stable MCI subjects during a 2 year period preceding
the conversion to AD. We included 48 stable MCI and 12 progressive MCI cases based on the availability of 3 serial
scans acquired with approximately 1 year scan interval. For the progressive MCI group, the third scan was acquired at the
time of the clinical diagnosis of AD, while the first two scans were acquired approximately 2 and 1 years earlier. For the
stable MCI group, the three scans were acquired at approximately 1 year intervals during a period free from significant
cognitive decline. We used longitudinal voxel-based morphometry (VBM) for mapping the progression of GM loss over
time. For the progressive MCI group, the cross-sectional analysis revealed areas of lower GM volumes in the parahippocampal
gyrus, precuneus and posterior cingulate 12 months before the AD diagnosis. For the longitudinal VBM analysis
the progressive MCI group revealed increased GM loss in cortical regions belonging to the temporal neocortex, parahippocampal
cortex, and cingulate gyrus. The frontal lobe, insula and the cerebellum were also affected. This accelerated atrophy
may offer new insights into the understanding of neurodegenerative pathology and the clinical relevance of these
changes remains to be verified by subsequent studies.
