Mapping hippocampal and ventricular change in Alzheimer disease

Laboratory of Neuro Imaging, Brain Mapping Division, Department of Neurology, UCLA School of Medicine, Los Angeles, CA 90095, USA.
NeuroImage (Impact Factor: 6.36). 09/2004; 22(4):1754-66. DOI: 10.1016/j.neuroimage.2004.03.040
Source: PubMed

ABSTRACT We developed an anatomical mapping technique to detect hippocampal and ventricular changes in Alzheimer disease (AD). The resulting maps are sensitive to longitudinal changes in brain structure as the disease progresses. An anatomical surface modeling approach was combined with surface-based statistics to visualize the region and rate of atrophy in serial MRI scans and isolate where these changes link with cognitive decline. Sixty-two [corrected] high-resolution MRI scans were acquired from 12 AD patients (mean [corrected] age +/- SE at first scan: 68.7 +/- 1.7 [corrected] years) and 14 matched controls (age: 71.4 +/- 0.9 years) [corrected] each scanned twice (1.9 +/- 0.2 [corrected] years apart, when all subjects are pooled [corrected] 3D parametric mesh models of the hippocampus and temporal horns were created in sequential scans and averaged across subjects to identify systematic patterns of atrophy. As an index of radial atrophy, 3D distance fields were generated relating each anatomical surface point to a medial curve threading down the medial axis of each structure. Hippocampal atrophic rates and ventricular expansion were assessed statistically using surface-based permutation testing and were faster in AD than in controls. Using color-coded maps and video sequences, these changes were visualized as they progressed anatomically over time. Additional maps localized regions where atrophic changes linked with cognitive decline. Temporal horn expansion maps were more sensitive to AD progression than maps of hippocampal atrophy, but both maps correlated with clinical deterioration. These quantitative, dynamic visualizations of hippocampal atrophy and ventricular expansion rates in aging and AD may provide a promising measure to track AD progression in drug trials.

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Available from: David M Gravano, Jul 15, 2015
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    • "This finding implies the difference of atrophy in terms of its extension and hemisphere dominance at different stages of AD. A closer inspection of the results shows that the top-ranked significant volumetric variables, e.g., hippocampus [30]–[32], ventricular [26], [33], cortical [30], [32], [34] and amygdala [33], [35] are all regions that have been proven to be effective predictors of AD and/or MCI by other research groups. The convergence of these findings comes in support of the merits and usability of the ranking system developed in this study. "
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    • "has already proved to be very powerful. Statistical shape analysis has been useful for studying normal age-related changes in subcortical nuclei, and for studying a number of other diseases (Ashburner, et al., 2003,Csernansky, et al., 1998,Csernansky, et al., 2000,Qiu, et al., 2010,Thompson, et al., 2004,Wang, et al., 2007). The study described here follows our previous work (Miller, et al., 2013) in which we used diffeomorphometry to measure subregional atrophy in three temporal lobe structures -entorhinal cortex (ERC), hippocampus and amygdala -in subjects with preclinical AD, i.e., individuals who were clinically and cognitively normal at the time of their MRI scans. "
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