title: Does MRI scan acceleration affect power to track brain change?
abstract: The Alzheimer's Disease Neuroimaging Initiative recently implemented accelerated T1-weighted structural imaging to reduce scan times. Faster scans may reduce study costs and patient attrition by accommodating people who cannot tolerate long scan sessions. However, little is known about how scan acceleration affects the power to detect longitudinal brain change. Using tensor-based morphometry, no significant difference was detected in numerical summaries of atrophy rates from accelerated and nonaccelerated scans in subgroups of patients with Alzheimer's disease, early or late mild cognitive impairment, or healthy controls over a 6- and 12-month scan interval. Whole-brain voxelwise mapping analyses revealed some apparent regional differences in 6-month atrophy rates when comparing all subjects irrespective of diagnosis (n = 345). No such whole-brain difference was detected for the 12-month scan interval (n = 156). Effect sizes for structural brain changes were not detectably different in accelerated versus nonaccelerated data. Scan acceleration may influence brain measures but has minimal effects on tensor-based morphometry-derived atrophy measures, at least over the 6- and 12-month intervals examined here.
authors.affiliation: Department of Neurology, Neuroscience Graduate Program, UCLA School of Medicine, Los Angeles, CA, USA; Department of Neurology, Imaging Genetics Center, Institute for Neuroimaging & Informatics, University of Southern California, Los Angeles, CA, USA.
authors.forename: Christopher R K
authors.initials: CR
authors.lastname: Ching
authors.affiliation: Department of Neurology, Imaging Genetics Center, Institute for Neuroimaging & Informatics, University of Southern California, Los Angeles, CA, USA.
authors.forename: Xue
authors.initials: X
authors.lastname: Hua
authors.affiliation: Department of Neurology, Imaging Genetics Center, Institute for Neuroimaging & Informatics, University of Southern California, Los Angeles, CA, USA.
authors.forename: Derrek P
authors.initials: DP
authors.lastname: Hibar
authors.affiliation: Department of Neurology, Mayo Clinic and Foundation, Rochester, MN, USA.
authors.forename: Chadwick P
authors.initials: CP
authors.lastname: Ward
authors.affiliation: Department of Neurology, Mayo Clinic and Foundation, Rochester, MN, USA.
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Gunter
authors.affiliation: Department of Neurology, Mayo Clinic and Foundation, Rochester, MN, USA.
authors.forename: Matt A
authors.initials: MA
authors.lastname: Bernstein
authors.affiliation: Department of Neurology, Mayo Clinic and Foundation, Rochester, MN, USA.
authors.forename: Clifford R
authors.initials: CR
authors.lastname: Jack
authors.affiliation: Department of Radiology, UCSF, San Francisco, CA, USA; Department of Medicine, UCSF, San Francisco, CA, USA; Department of Psychiatry, UCSF, San Francisco, CA, USA; Center for Imaging of Neurodegenerative Diseases (CIND), Department Veterans Affairs Medical Center, San Francisco, CA, USA.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Weiner
authors.affiliation: Department of Neurology, Neuroscience Graduate Program, UCLA School of Medicine, Los Angeles, CA, USA; Department of Neurology, Imaging Genetics Center, Institute for Neuroimaging & Informatics, University of Southern California, Los Angeles, CA, USA; Department of Neurology, USC, Los Angeles, CA, USA; Department of Psychiatry, USC, Los Angeles, CA, USA; Department of Radiology, USC, Los Angeles, CA, USA; Department of Engineering, USC, Los Angeles, CA, USA; Department of Pediatrics, USC, Los Angeles, CA, USA; Department of Ophthalmology, USC, Los Angeles, CA, USA. Electronic address: pthomp@usc.edu.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Thompson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis* / Q000473:pathology*; D001284:Atrophy; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods; D060825:Cognitive Dysfunction / Q000175:diagnosis / Q000473:pathology; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D059906:Neuroimaging / Q000379:methods*; D013997:Time Factors
keywords: Alzheimer's disease; Biomarker; Drug trial enrichment; Longitudinal; MRI; Neuroimaging; Scan acceleration; Tensor-based morphometry