Temporal Subtraction Method for Thoracic MDCT Image by Using Intensity Gradient Information

Recently, CAD system has been introduced as a visual screening method in medical field. Also, temporal subtraction method, which enhances temporal changes such as the abnormalities on the image, is implemented as one of technique for CAD by subtracting previous image from current one. Image registration techniques are required for the temporal subtraction method. If the accuracy of image registration is insufficiently, normal structure elements which should be removed are remained on subtraction image. In this study, a novel image registration method for temporal subtraction technique on thoracic MDCT images has been developed to reduce the subtraction artifacts by using intensity gradient information. The proposed method has been applied to thoracic MDCT images, and its efficiency has been indicated