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Brain Images of Normal Subjects (BRAINS) Bank
David Alexander Dickie Dr Dominic E. Job
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Background Age and disease affect brain structure
The effects are disparate Much MRI data are needed ~300 normal ageing (>60yrs) subjects “Atlases” of the aged brain are limited
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Background Brain Images of Normal Subjects (BRAINS) bank >1000 normal sbjs >60yrs BRAINS models and atlases calculate distributions (not assume) Data requires much image processing Pilot ~200 normal, ~200 AD sjbs, years
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MR Image processing
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Brain extraction
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Brain extraction Brain Extraction Tool (BET) commonly used
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Brain extraction Brain Extraction Tool (BET) commonly used
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Template based brain extraction
Advanced Normalization Tools (ANTS) Uses diffeomorphic (super nonlinear) spatial normalisation
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Image registration
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ANTS diffeomorphic spatial normalisation
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ANTS diffeomorphic spatial normalisation
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ANTS diffeomorphic spatial normalisation
But catastrophes still happen
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ANTS diffeomorphic spatial normalisation
ANTS takes ~1 hour per subject (computer) Still requires by slice checking ~10 minutes checking per subject 460 subjects took ~2.5 months Catastrophes still happen >1000 subjects in full-scale study
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Data driven brain volume models
Statistical models oft used in brain imaging The general linear model (GLM) Assume data generation and distribution Transformations lose natural data, have risks, complexity Image banks support data driven models
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Brains are heteroscedastic
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See, they’re different
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Data driven vs. general models
DDPM has ~65% less error
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Data driven brain voxel models
Statistical voxel based morphometry (VBM) The general linear model (GLM) Assumes data generation and distribution Transformations lose natural data, smoothing Image banks support data driven models
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BRAINS atlases BRAINS MNI 152
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Image registration
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BRAINS atlases 1
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BRAINS atlases Normal Alzheimer’s Red=95th
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White matter lesions
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White matter lesions Percentile 95 75 50 25 5 A
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White matter lesions Percentile 95 75 50 25 5 A
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Percentiles of grey matter density in a normal ageing and Alzheimer’s disease subject
5th 25th 50th 75th 95th Alzheimer’s disease has lowest percentiles of GM in MTL
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Percentiles of grey matter density in a normal ageing and Alzheimer’s disease subject
Bad OK Good Alzheimer’s disease has lowest percentiles of GM in MTL
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Median percentile image of grey matter density in Alzheimer’s disease (n=49) and control (n=49) subjects Alzheimer’s Control Percentile 5th 25th 50th 75th 95th Alzheimer’s has lowest percentiles of GM across the cortex, specifically hippocampus.
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BRAINS vs. VBM
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BRAINS vs. VBM Needs data Less assumptions Anatomical resolution
Specific anatomy Individuals Size of differences Simpler
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SINAPSE SPIRIT, MRC, Tony Watson
Thank you
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