Design And Realization Of Visualization Module Used In HIFU Localization Software

Nowadays High Intensity Focused Ultrasound (HIFU) has been a hotspot of noninvasive therapy in solid tumor treatment. Different from other treatments, its mechanism is focus with high-energy ultrasound in treated target area in vivo, to coagulate specified tissues and cause to necrosis in a high temperature(above 65 C ) at moment.The key of HIFU treatment is the accurate localization of target areas. Because of its quick imaging, convenience and low-cost, the B-mode ultrasound imaging system is the mostly used localization method. However, it has difficulty of accurate three-dimensional localization due to its low image quality. Consequently, an effective method of three-dimensional localization has become a big problem to be resolved in HIFU treatment.With the development of computer technology, the technology of three-dimensional reconstruction has become an important study area in computer graphic and image field. Three-dimensional reconstruct and visualization may help HIFU doctor localize the target areas, make sure the safety of other areas.To realize the image-guide HIFU localization system, our research team divided the big project into three modules (image segmentation and registration, visualization, interactive user interface). This paper studies the design and realization of visualization module and refers to its process based on VTK and the key technique in direct volume rendering.The dissertation includes two parts below.Part one is about the key technique in direct volume rendering as the theory basis. This part includes three chapters. Chapter one introduces visualization in medical images. In Chapter two we talk about the design, deduction and calculation process of transfer function in detail. Chapter three as a conclusion is the interpretation of chapter two.Part two is the practice part based on part one. We use visual C++ developer environment and visualization toolkit to develop the visualization module. This part includes five chapters. Chapter four introduces the whole design. Chapter five to seven introduces the development process of sub-modules from medical image reading, medical image processing to medical image visualization separately. Chapter eight as a conclusion gives a whole example.The visualization module realized in this dissertation can read standard medical image files, process and visualization in two or three-dimension. With the design method of transfer function talked in this dissertation and a little few proper by-hands adjustment, we can get satisfying three-dimensional visualization effects. In the future, combining with other modules (image segmentation, registration and interactive user interface), we will complete the whole project and realize the image-guide HIFU localization system.