Three-dimensional non-rigid registration of thoracic CT image based on finite element method

Developing of computer aided diagnosis (CAD) system which analyzes the medical image by a computer and provides the doctor as a "second opinion" the result is becoming increasingly popular. Temporal subtraction technique which is one of the CAD systems supports the observation by performing the differential operation of the current image and the previous one of the same patient and emphasizing temporal changes. Process of registration between images exist in this technique, this accuracy is greatly affects to the temporal difference image. However, registration method adaptable to a variety of images with high accuracy has not been established yet. So in this paper, we propose a three-dimensional non-rigid image registration method generic and high precision based on finite element method (FEM). In the proposed method, in order to improve the high cost is the biggest problem of the FEM, introducing the feature point detection in generating a tetrahedral mesh model. Furthermore, we introduce global matching to achieve an improvement of the execution efficiency. In this paper, we verify the effectiveness by the result applying the model data and 3D thoracic CT Images the proposed method.