Statistical shape analysis of hippocampus in temporal lobe epilepsy based on Laplace-Beltrami eigenfunction level sets

Shape analysis plays an important role in many medical imaging studies. One of the recent shape analysis methods uses the Laplace Beltrami operator. This article studies the deformation of hippocampus in temporal lobe epilepsy based on Laplace Beltrami operator. The level sets of Laplace Beltrami eigenfunctions are automatically extracted and their circumferences are used as a measure of thickness. Statistical maps of corresponding level sets are computed and visualized using an average atlas. The results suggest significant deformation in both ipsilateral and contralateral hippocampi of epileptic patients. Also it is shown that the pattern of deformation in the seizer side and the other hippocampi are different. Relative to the previous statistical shape analysis studies in epilepsy, the proposed method gives comparable results with the advantage of no need for alignment.