Editing Scale-invariant feature transform (section)

=== Analyzing the Human Brain in 3D Magnetic Resonance Images ===
The Feature-based [[Brain morphometry|Morphometry]] (FBM) technique<ref name="Toews2010" /> uses extrema in a difference of Gaussian scale-space to analyze and classify 3D [[magnetic resonance image]]s (MRIs) of the human brain. FBM models the image probabilistically as a collage of independent features, conditional on image geometry and group labels, e.g. healthy subjects and subjects with [[Alzheimer's disease]] (AD). Features are first extracted in individual images from a 4D difference of Gaussian scale-space, then modeled in terms of their appearance, geometry and group co-occurrence statistics across a set of images. FBM was validated in the analysis of AD using a set of ~200 volumetric MRIs of the human brain, automatically identifying established indicators of AD in the brain and classifying mild AD in new images with a rate of 80%.<ref name=Toews2010 />