Development of Techniques for 3D Shape Representation

Variability of Shapes: Left hippocampal structure segmented from 3D Magnetic resonance datasets by manual outlining. The surfaces of the volumetric shapes have been parametrized and transformed into series of 3D spherical harmonics. Reconstructions of 22 structures are shown (in collaboration with Gabor Skekely and Andras Kelemen, ETH Zurich). Martha Shenton and Ron Kikinis, Brigham and Women's Hospital Harvard Medical School, are acknowledged for providing the original MRI and the segmented datasets.

First and second eigenshapes. The movies visualize the first and second largest eigenmodes of variation, i.e. deviation from the mean shape. The deviation +/- 2 standard deviations are shown.

3D medial skeletons of the hippocampal structures (in collaboration with Dominique Attali, Grenoble). Medial axis representations represent the global shape and local width of structures and offer advantages over surface-based shape analysis.