Age- and sex-related effects on the neuroanatomy of healthy elderly

Groupe d'Imagerie Neurofonctionnelle, UMR 6194, CNRS, CEA, Universités de Caen et Paris 5, GIP Cyceron, BP5229, F-14074 Caen, France.
NeuroImage (Impact Factor: 6.36). 08/2005; 26(3):900-11. DOI: 10.1016/j.neuroimage.2005.02.042
Source: PubMed

ABSTRACT Effects of age and sex, and their interaction on the structural brain anatomy of healthy elderly were assessed thanks to a cross-sectional study of a cohort of 662 subjects aged from 63 to 75 years. T1- and T2-weighted MRI scans were acquired in each subject and further processed using a voxel-based approach that was optimized for the identification of the cerebrospinal fluid (CSF) compartment. Analysis of covariance revealed a classical neuroanatomy sexual dimorphism, men exhibiting larger gray matter (GM), white matter (WM), and CSF compartment volumes, together with larger WM and CSF fractions, whereas women showed larger GM fraction. GM and WM were found to significantly decrease with age, while CSF volume significantly increased. Tissue probability map analysis showed that the highest rates of GM atrophy in this age range were localized in primary cortices, the angular and superior parietal gyri, the orbital part of the prefrontal cortex, and in the hippocampal region. There was no significant interaction between "Sex" and "Age" for any of the tissue volumes, as well as for any of the tissue probability maps. These findings indicate that brain atrophy during the seventh and eighth decades of life is ubiquitous and proceeds at a rate that is not modulated by "Sex".

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Available from: Fabrice Crivello, Aug 07, 2015
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    • "For the purpose of the present study, the hippocampus was considered as a region of specific interest (ROI) given that it is a highly recognized imaging marker of brain aging (Hof and Morrison, 2004). Similar to previous studies (Lemaître et al., 2005b; Crivello et al., 2010) left and right hippocampus volumes were automatically estimated by integrating the voxel intensities of the modulated GM partition images within hippocampus limits as defined by the AAL atlas (Tzourio-Mazoyer et al., 2002). Statistical analysis was performed on the total hippocampus volume (HIP), i.e., on sum of the left and right volumes. "
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    Frontiers in Aging Neuroscience 11/2014; 6:299. DOI:10.3389/fnagi.2014.00299 · 2.84 Impact Factor
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    • "MR images were segmented and stereotactically normalized to the Montreal Neurological Institute (MNI) space using a combined segmentation and registration approach [25] as implemented in the Statistical Parametric Mapping 8 (SPM8) software package (Wellcome Trust Centre for Neuroimaging, London, UK). Preexisting, freely available prior tissue probability maps for GM, white matter (WM), and cerebrospinal fluid (CSF) were used to assist segmentation and registration [26]. The default setting of the unified segmentation engine was used as described in Arlt et al. [27]. "
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    Journal of Alzheimer's disease: JAD 09/2014; 44(1). DOI:10.3233/JAD-141446 · 4.15 Impact Factor
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    • "A topographic histogram (i.e. damaged tissue overlap map) depicting the voxel-wise prevalence of infarct, peri-infarct damage, and white matter hypointensities combined (normalized to a custom older adult template (Lemaitre et al., 2005)) is shown in Fig. 2. FLAIR imaging is often utilized as the clinical standard for quantifying white matter pathology due to its ability to more conspicuously capture infarctions and white matter disease (Alexander et al., 1996). Because the equivalence of different MRI metrics for quantifying white matter pathology (e.g., FLAIR hyperintensities versus T1-weighted hypointensities) has not yet been established, white matter hyperintensities and periventricular hyperintensities were also quantified using Fazekas ratings (Fazekas et al., 1987, see Table 2) for a subset of 38 participants for which non-volumetric FLAIR images were available. "
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