Study On 3 Digital Reconstruction Of Anatomical Structure Of Liver Based On CT Images

Digital Human liver model is a hot spot in digital medical and image analysis research fields. Many researchers pay close attention to it in recent years. The purpose of digital liver reconstruction is to segment and visualize the liver and vessels in abdomen images. The reconstruction result can be a guidance and evidence of clinical diagnosis and resection by supplying a clear, visual and anatomical liver model. So research on the digital liver model reconstruction is significant to science and worthy in clinical application.In this dissertation, we survey medical image processing and 3d reconstruction technology and analyze digital anatomical structure of liver. A new digital liver anatomical model reconstruction method is presented, and this method reconstruct liver anatomical model as doctor desired. The main aspects of research include:Firstly, we analyze the format of medical image and the generally used image format. We research on the grey level transformation, noises moving of abdomen CT images and transform them to bitmap images. This preprocessing procedure is to ensure the efficiency and accuracy.Secondly, we survey the main image segmentation methods and analyze the properties of abdomen CT images. A liver segmentation method based on the slowly changed liver contours is presented. And a new blood vessel system extraction method is presented, as well. Experiments show the segmentation methods are effective.Thirdly, for the application of virtual liver resection, a method of dividing liver functional segments is proposed. The first step is to partition the vessel branches by doctor giving a point. The second step is to label these branches. The third step is to divide the liver functional segments according to those labeled branches by a minimum spatial distance with window algorithm.Finally, a simple but useful interactive hepatectomy plannning system is implemented to visualize the digital liver model to display the inner anatomy structure and measure the volume of liver segments. Experiments are carried out to evaluate the performance of the methods above. It supports the feasibility of these methods.