Skull Stripping Using Geodesic Active Contours in Magnetic Resonance Images

Skull stripping is an important image processing step in many neuroimaging studies. In this paper, a novel scheme based on a level sets representation of the geodesic active contour (GAC) is employed to detect the boundary of the skull. This approach is based on the relation between active contours and the computation of geodesics (minimal length curves). The contour is evolved from inside the MR image under the influence of geometric measures of the MR image. Before the application of GAC, the MR image is roughly done into two regions, brain and nonbrain. The centroid of the brain region is obtained which is used for drawing an ellipse situated well inside the brain region. This ellipse is the initial contour. After the model converges to a stable solution, the obtained mask is processed using morphological operators. This mask is then used to give the final segmented output.