A 3-D Non-Rigid Warping Method Based on Free Formed Deformation for Temporal Subtraction on Thoracic MDCT Images

Abstract

Recently, the development of the Computer Aided Diagnoses (CAD) systems has been rapidly remarked. As one of the CAD systems, temporal subtraction technique can emphasize the temporal changes of interested regions by subtracting a previous image from a current image. However, subtraction artifacts are still remained due to misregistration, which caused by the variation of pose and inhalation differences when a patient accepts CT inspection at different times. Therefore, high accurate registration technique between a previous image and a current image is necessary. The purpose of this paper is to propose a nonrigid warping algorithm in local image matching based on the feature-driven Free Formed Deformation (FFD). The proposal was performed on thoracic MDCT images and the satisfactory results were obtained.

Mean projection image application to the automatic rotation axis alignment in cone-beam CT

“…To a certain extent, the mean projection image p(x, z) may be regarded as a fusion of the measured object data and it may be generalized in the form of linear functional depending on the whole collection of projection images [33,34].…”