Pulmonary Nodule Image Volume Rendering Research

Diagnosing the pulmonary nodules with2D lung CT image is difficult and inaccurate. The medicine is in need of an effective means that can render the3D lung image with high quality and can high-lighting the suspect pulmonary nodules which can help diagnosing the pulmonary nodules. This paper focuses on this demand and study the fast-rendering, high-lighting the interesting information. In addition, it is also a worth studying problem that how to build a friendly user interface.This paper studies the process and principle of the volume rendering, transfer function designing and the fast-render technology. The main research results are obtained as follows in this paper:(1) The real-time ray casting volume rendering algorithm is discussed and implemented in this paper, giving the doctors three-dimensional images of the lungs.(2) The pulmonary nodules in the data set are the most interesting. In order to high-light the suspect pulmonary nodules, a transfer function designing method is put forward. First, the images are segmented. Second, the images are reconstructed into3D data set. Then3D features are extracted. Through the classifier, pulmonary nodules are classified. Final, the transfer functions are set up in each class. This transfer function designing method can high-lighting the suspect pulmonary nodules and reduce the missed diagnosis.(3) For fast-rendering, an adaptive accelerated sampling algorithm base on the characteristics of the data set is presented.(4) Sometimes the pulmonary nodules are covered. In order to wipe off the obstructions, a cutting algorithm based on the volume mark is implemented. This implementation will not slow down the rendering.The fast real-time high quality volume rendering based on GPU technology is discussed in this paper, and the acceleration technology, higher dimensional transfer function design, the ray casting algorithm and transfer function designing method are explored deeply in this paper. The work stated in this thesis has good meanings for medical practice and provides a good reference and new ideas for researcher.