Volume Rendering Technology Based On Optical Coherence Tomography Surgical Navigation System

Optical Coherence Tomography(OCT),as a high resolution in vivo medical imaging technology,plays an important role in medical diagnosis due to its advantages of non-invasion,non-injury,high resolution and high sensitivity.In recent years,with the significant development of optical technologies such as high-speed tunable laser light source(sweep frequency light source),high-speed CCD camera and CMOS detector,OCT based surgical navigation system is under development.Three-dimensional reconstruction based on OCT slice images has become a research focus in the field of OCT images.The research content of this paper is the three-dimensional reconstruction of OCT images.The main research contents of this paper include volume rendering based on OCT slice data,real-time 3d reconstruction of OCT surgical navigation system,and 3d image dither removing of OCT retinal fundus.1.Based on the basic principle of volume rendering,an OCT image volume rendering method based on ray casting algorithm is implemented,and a solution to the problem of the ray projection algorithm in the three-dimensional reconstruction of OCT images is proposed.Finally,a 3d reconstruction software is designed and implemented for OCT data,and the related image functions are realized.The results show that the 3d reconstruction software implemented in this paper can well realize the volume rendering of OCT slice images.2.In this paper,the main functions and key performance requirements of the threedimensional reconstruction module of slice data in OCT surgical navigation system were analyzed.Ray casting algorithm based on OpenGL was implemented to realize the rapid three-dimensional reconstruction of OCT images.Then,the real-time three-dimensional reconstruction function of OCT surgical navigation system was realized by combining pixel buffer technology.It also solves the problem of 3d texture frame disorder which is caused by the slow data processing speed of OCT system.3.In the three-dimensional reconstruction of OCT fundus retinal images,the 3d images are distorted and deformed.Through analysis,it is found that this problem is mainly caused by the deviation of OCT section data of adjacent frames during the 3d scanning process due to the irregular jitter and heartbeat of the human body,which results in the distortion and deformation of the 3d reconstruction images.In this paper,according to the retinal structure of the fundus and the three-dimensional scanning characteristics of the OCT system,curve fitting method was used to calibrate the deviation of OCT retinal data,effectively reducing the distortion of retinal 3d reconstruction images.