Open AccessComparing 3 T and 1.5 T MRI for tracking Alzheimer's disease progression with tensor‐based morphometry
Author(s) -
Ho April J.,
Hua Xue,
Lee Suh,
Leow Alex D.,
Yanovsky Igor,
Gutman Boris,
Dinov Ivo D.,
Leporé Natasha,
Stein Jason L.,
Toga Arthur W.,
Jack Clifford R.,
Bernstein Matt A.,
Reiman Eric M.,
Harvey Danielle J.,
Kornak John,
Schuff Norbert,
Alexander Gene E.,
Weiner Michael W.,
Thompson Paul M.
Publication year - 2010
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.20882
Subject(s) - atrophy , clinical dementia rating , dementia , alzheimer's disease , psychology , magnetic resonance imaging , temporal lobe , medicine , cognitive decline , cardiology , disease , nuclear medicine , audiology , neuroscience , radiology , epilepsy
A key question in designing MRI‐based clinical trials is how the main magnetic field strength of the scanner affects the power to detect disease effects. In 110 subjects scanned longitudinally at both 3.0 and 1.5 T, including 24 patients with Alzheimer's Disease (AD) [74.8 ± 9.2 years, MMSE: 22.6 ± 2.0 at baseline], 51 individuals with mild cognitive impairment (MCI) [74.1 ± 8.0 years, MMSE: 26.6 ± 2.0], and 35 controls [75.9 ± 4.6 years, MMSE: 29.3 ± 0.8], we assessed whether higher‐field MR imaging offers higher or lower power to detect longitudinal changes in the brain, using tensor‐based morphometry (TBM) to reveal the location of progressive atrophy. As expected, at both field strengths, progressive atrophy was widespread in AD and more spatially restricted in MCI. Power analysis revealed that, to detect a 25% slowing of atrophy (with 80% power), 37 AD and 108 MCI subjects would be needed at 1.5 T versus 49 AD and 166 MCI subjects at 3 T; however, the increased power at 1.5 T was not statistically significant (α = 0.05) either for TBM, or for SIENA, a related method for computing volume loss rates. Analysis of cumulative distribution functions and false discovery rates showed that, at both field strengths, temporal lobe atrophy rates were correlated with interval decline in Alzheimer's Disease Assessment Scale‐cognitive subscale (ADAS‐cog), mini‐mental status exam (MMSE), and Clinical Dementia Rating sum‐of‐boxes (CDR‐SB) scores. Overall, 1.5 and 3 T scans did not significantly differ in their power to detect neurodegenerative changes over a year. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.