is defined as the measurement of objects in an image. It has become increasingly important since the advent of non-invasive magnetic resonance imaging (MRI) which is providing large volumes of data from normal as well of abnormal individuals and allows the time changes to be studied.
Applications are the measurement of tissue shapes from tumors, organ volumes like heart or brain, or specific anatomical structures in the field of neurology or psychiatry.
Voxel-Based Morphometry (VBM) is a computational approach to neuroanatomy that measures differences in local concentrations of brain tissue, through a voxel-wise comparison of multiple brain images.
The procedure is relatively straightforward and involves spatially normalizing high-resolution images from all the subjects in the study into the same stereotactic space, the so-called talairach space. This is followed by segmenting the gray matter from the spatially normalized images and smoothing the gray-matter segments. A comparison of the density of grey matter in the two groups is then conducted in order to identify differences in the concentration of grey matter that are related to specific variables under study.
High-field MRI at 3T and beyond offers the potential for high-resolution VBM of smaller brain structures measuring 3D brain datasets with submillimeter resolution on all 3 axes. Examples from our 3T MRT: