This paper describes a preliminary study on generating a respiratory motion model using two differnt phases of 4D CT images for the use in a bronchoscope guidance system, where the position and orientation of the bronchoscope is determined and visualized. Present systems use a preinterventional CT image, which is taken at a certain phase of the respiratory cycle as a map, so it is difficult to cope with deformations of the bronchus by respiratory and heart motion. This causes position and orientation error. Therefore we propose to update the position of the bronchoscope by obtaining deformed information of the bronchus from two 3DCT images at different phases respiratory and constructing a respiratory motion model to cope with the deformation of the bronchus. In this paper we discuss interpolation methods to estimate the deformation between the two images taken in inspiration and expiration. We interpolate anatomical feature points between inspiration and expiration. We evaluate linear and trigonometric interpolation on ten CT images. A comparition of our two phases interpolation method to 4D CT data shows average estimation errors of 1.32 mm and 1.17 mm respectively.     «

This paper describes a preliminary study on generating a respiratory motion model using two differnt phases of 4D CT images for the use in a bronchoscope guidance system, where the position and orientation of the bronchoscope is determined and visualized. Present systems use a preinterventional CT image, which is taken at a certain phase of the respiratory cycle as a map, so it is difficult to cope with deformations of the bronchus by respiratory and heart motion. This causes position and orient...     »