title: Diffusion tensor imaging and tractography of the white matter in normal aging: The rate-of-change differs between segments within tracts.
abstract: Knowledge concerning the normal aging of cerebral white matter will improve our understanding of abnormal changes in neurodegenerative diseases. The microstructural basis of white matter maturation and aging can be investigated using diffusion tensor imaging (DTI). Generally, diffusion anisotropy increases during childhood and adolescence followed by a decline in middle age. However, this process is subject to spatial variations between tracts. The aim of this study was to investigate to what extent age-related variations also occur within tracts. DTI parameters were compared between segments of two white matter tracts, the cingulate bundle (CB) and the inferior fronto-occipital fasciculus (IFO), in 257 healthy individuals between 13 and 84years of age. Segments of the CB and the IFO were extracted and parameters for each segment were averaged across the hemispheres. The data was analysed as a function of age. Results show that age-related changes differ both between and within individual tracts. Different age trajectories were observed in all segments of the analysed tracts for all DTI parameters. In conclusion, aging does not affect white matter tracts uniformly but is regionally specific; both between and within white matter tracts.
authors.affiliation: Department of Surgical Sciences/Radiology, Uppsala University, Uppsala, Sweden. Electronic address: johanna.martensson@radiol.uu.se.
authors.forename: J
authors.initials: J
authors.lastname: Mårtensson
authors.affiliation: Center for Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden. Electronic address: jimmy.latt@med.lu.se.
authors.forename: J
authors.initials: J
authors.lastname: Lätt
authors.affiliation: Department of Psychology, Uppsala University, Uppsala, Sweden. Electronic address: fredrik.ahs@psyk.uu.se.
authors.forename: F
authors.initials: F
authors.lastname: Åhs
authors.affiliation: Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden. Electronic address: mats.fredrikson@psyk.uu.se.
authors.forename: M
authors.initials: M
authors.lastname: Fredrikson
authors.affiliation: Department of Psychology, Uppsala University, Uppsala, Sweden. Electronic address: hedvig.soderlund@psyk.uu.se.
authors.forename: H
authors.initials: H
authors.lastname: Söderlund
authors.affiliation: Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden. Electronic address: helgi.schioth@neuro.uu.se.
authors.forename: H B
authors.initials: HB
authors.lastname: Schiöth
authors.affiliation: University of Groningen, University Medical Center Groningen, Department of Neurology, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Kok
authors.affiliation: University of Groningen, University Medical Center Groningen, Department of Neurology, The Netherlands. Electronic address: h.p.h.kremer@umcg.nl.
authors.forename: B
authors.initials: B
authors.lastname: Kremer
authors.affiliation: Department of Diagnostic Radiology, Skåne University Hospital, Lund, Sweden. Electronic address: danielle.van_westen@med.lu.se.
authors.forename: Danielle
authors.initials: D
authors.lastname: van Westen
authors.affiliation: Department of Surgical Sciences/Radiology, Uppsala University, Uppsala, Sweden. Electronic address: elna-marie.larsson@radiol.uu.se.
authors.forename: E-M
authors.initials: EM
authors.lastname: Larsson
authors.affiliation: Lund University Bioimaging Center, Lund University, Lund, Sweden. Electronic address: markus.nilsson@med.lu.se.
authors.forename: M
authors.initials: M
authors.lastname: Nilsson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D066127:White Matter / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D055815:Young Adult
keywords: Aging; Cingulum; Inferior fronto-occipital fasciculus; Tractography; White matter degeneration; White matter tract