The Institute For Research In Cognitive Science Elastically Deforming a Three-Dimensional Atlas to Match Anatomical Brain Images

To evaluate our system for elastically deforming a three dimensional atlas to match anatomical brain images six deformed versions of an atlas were generated The deformed atlases were created by elastically mapping an anatomical brain atlas onto di erent MRI brain image volumes The mapping matches the edges of the ventricles and the surface of the brain the resultant deformations are propagated through the atlas volume deforming the remainder of the structures in the process The atlas was then elastically matched to its deformed versions The accuracy of the resultant matches was evaluated by determining the correspondence of cortical and subcortical structures The system on average matched the centroid of a structure to within mm of its true position and t a structure to within of its true volume The overlap between the matched and true structures de ned by the ratio between the volume of their intersection and the volume of their union averaged When the gray white interface was included for matching the mean overlap improved to each structure was matched to within mm of its true position and t to within of its true volume Preliminary studies were also made to determine the e ect of the compliance of the atlas on the resultant match This work was supported by the U S P H S under Program Project Grant NS To appear in Journal of Computer Assisted Tomography