FAST

Overview

FAST (FMRIB's Automated Segmentation Tool) segments a 3D image of the brain into different tissue types (Grey Matter, White Matter, CSF, etc.), whilst also correcting for spatial intensity variations (also known as bias field or RF inhomogeneities). The underlying method is based on a hidden Markov random field model and an associated Expectation-Maximization algorithm. The whole process is fully automated and can also produce a bias field-corrected input image and a probabilistic and/or partial volume tissue segmentation. It is robust and reliable, compared to most finite mixture model-based methods, which are sensitive to noise. It is also very fast. Currently, it takes less than ten minutes to segment a 256x256x50 volume on a 500MHz Pentinum III PC.

Papers

A paper on this research has been published in IEEE TMI. For more detail, see a report (PS/PDF/HTML) or view a slideshow.

Software

FAST is available as part of the FMRIB Software Library.