The Technology Of Interactive Virtual Hepatic Surgery System

To be able to capture the liver list image from CT to re-construct 3D entity, to further accurately indicate the 3D information of the liver as well as the inner vessel structure and abnormality. Therefore, the virtual liver removal can be operated smoothly, and, at the same time, the volume of the remained liver can be measured. In this way, the patient will be able to simulate and assess the operation more visually and directly, thus, they will be able to choose the best operation project before they are taken into the operation room. The advantage of this interactive system is that the strategy of the operation can be more purposely and interactively to ensure a higher level of the safety of the operation.The main work of this paper:(1) At the part of image pretreatment, first, this paper improve the window function on mapping of the DICOM data to make it be more smooth when accommodate.Then it utilize mid-filter, mean filter and wavelet filter accomplishing the work of image denoisin. At last, to protect the edge of liner and advance the resolution factor of inner-layer, the slice is insered with an improving linearity-layer contour interpolation method.(2) At the part of image segmentation, on reacher of the fractal dimension value of different apparatus in CT image, it proves the conclusion that texture characteristic of the same apparatus in CT image will not be influenced by the noise and contrast. On the base of this, this paper presents a fractal dimension and shape simulation based method for outline distilling of serial CT liver-image. When choosing the control point, we verify the max-grad and the fractal dimension value on the region.(3) At the part of data treatment, a method of distilling optimization path in the distance-field is be used to distill the framework of liver blood vessel. It chooses main points in the distance-field and connects them with optimization path between the root and twig point of the vessel, which are labled by hand.All of our data are provided by The First Hospital of FuJian Medical University .The post-re-construction has a greater visual effect, and can be observed from any angel. In addition, the relationship among the main vessels in the liver can be displayed clearly, therefore, the actual condition of the liver and inner vessel system. Moreover, the CT image of the abnormal area can be cut variously according to different purposes, and volume of the area that is taken off is measurable as well.