Non-rigid registration with use of hardware-based 3D Bézier functions

Abstract

In this paper we introduce a new method for non-rigid voxelbased registration. In many medical applications there is a need to establish an alignment between two image datasets. Often a registration of a time-shifted medical image sequence with appearing deformation of soft tissue (e.g. pre- and intraoperative data) has to be conducted. Soft tissue deformations are usually highly non-linear. For the handling of this phenomenon and for obtaining an optimal non-linear alignment of respective datasets we transform one of them using 3D B´ezier functions, which provides some inherent smoothness as well as elasticity. In order to find the optimal transformation, many evaluations of this B´ezier function are necessary. In order to make the method more efficient, graphics hardware is extensively used. We applied our non-rigid algorithm successfully to MR brain images in several clinical cases and showed its value.