Research Of Precision Improvement And Path Planning Based On Lung Puncture Surgical Navigation

Pulmonary tumor is one of the highest fatality rate diseases in the world, and the lung biopsy surgery directed by CT image is the most conventional ways to detect pulmonary tumor, but the surgery makes patient be punctured and radiated repeatedly. The lung biopsy based on surgical navigation will reduce the number of puncture, radiation and trauma, and improve the precision and success rate. But the navigation precision and the puncture accuracy are the foundation of these. So, under the condition of we have developed a surgical navigation platform, this paper mainly has conducted some researches about the precision promotion and path planning based on the lung puncture surgical navigation.First, the precision promotion based on the lung puncture surgical navigation could be divided into four parts:1) According to the working lung puncture surgical navigation system at this present stage, for the first time, we analysis and classify the errors in the process of its application, and divided the whole error into two categories and six subclasses, each of subclass also has a detail division. Also, the errors that can be avoided or reduced and unable be overcome have been separated out, which provide the guidance and the theoretical basis for the related scientific researchers to further improve the precision of navigation system.2) We have proposed a method that based on the surface projection correction to segment the point set that at the bottom of marker center hole, which promoted the markers segmentation result from point to the point set, and improved the accuracy and comprehensiveness of markers’segmentation and location. This method can be widely used in the segmentation of marked points in nerve, bone and spine surgery navigation system.3) On the basis of markers segmentation, catching the markers point set in the space coordinates, for the first time, we used the ICP algorithm to do registration, and promoted the registration from point to point to the point set to point set. It had greatly improved the precision of space registration, and this method also can be widely used in other surgical navigation system.4) Using the homemade simulated chest phantom, we had conducted some related experiments to research how the fiducial markers on the surface of human body effect the registration precision, and also tested the difference between the Fitzpatrick TRE’s calculation method and the actual TRE, and got a series of conclusions from these experiments.Then, the path planning based on the lung puncture surgical navigation could be divided into two parts:1) We have taken a fast and accurate segmentation and extraction of the important organs (skin, bone, lung parenchyma, trachea, blood vessels) in the chest, and extracted the surface and the skeleton of the trachea and blood vessels, and calculated out the corresponding radius.2) Based on the segmentation result, and according to the existing medical knowledge and the situation of actual lung puncture, for the first time, we proposed a model that used to quantify and evaluate the lung puncture path risk, and based on this model, we also proposed three different planning situations to calculate out the best puncture path. Through the image data simulation testing, we achieved the very accurate result.Finally, based on these two aspects of much of the original studies, we have greatly improved the lung puncture surgery navigation system’s precision and accuracy of puncture, and promoted the surgery navigation system application into the of lung puncture, and expanded the application range of surgical navigation system, which laid a solid foundation for the further clinical test.