Image Navigation And Registration In Interventional Therapy Of Liver

This paper has done some work about image guided system of Interventional therapy. Interventional therapy is curing by probing surgical instruments into the patient body under the guidance of medical image. The premise of interventional therapy is the guidance of medical image, and the key of interventional therapy is placing the surgical instruments to the center of disease in the body of patient accurately. Three dimensional image guided system is completed in this paper because it is difficult to positioning the area of the tumor precisely, with the guidance of Conventional B-mode ultrasound for lack of three-dimensional image information, these factors seriously affect the treatment effect.In our software system, work of image segmentation and volume reconstruction has been finished, and satisfactory results are got. The main work in this paper is to do some research on registration.At first, virtual surgical environment used as model of navigation is established, that is adding path planning, coordinate system and virtual probe on the three dimensional body, and the path planning become more precise with the help of two dimensional measurement. The virtual environment used to guide the surgery is complete.Secondly, I do some systematic research on the registration part of the image guided system. In aspect of two-dimensional registration, In order to modify the deformation of the tissue, B-spine deformation grids is used, and some satisfactory results is received in deformable registration by method of iterating the control points. And also the algorism is improved by exacting Region Of Interest(ROI), which make the calculation more precisely and more rapidly.At last, 2D-3D registration of CT images and X-ray image is achieved by adopting Digitally Reconstructed Radiographs(DRR), a technique aimed getting virtual X-ray image. And also the coordinate transform of three dimensional is got in the registration.