Research On The Technique Of 3D Reconstruction And Measurement Of Vertebra Based On CT Image

With the development of computerized tomography and nuclear magnetic resonance, three-dimensional reconstruction based on layer data have become one of the most popular research topics not only at home but also abroad. Using three-dimensional imaging for spatial structure morphology and quantitative research has become an important shape testing means of medical research. Vertebral measurements have been widely employed in many fields, including the anthropology, anatomy, clinical medicine, forensic medicine, medical equipment design, biomedical engineering and others.This thesis studied on the three-dimensional reconstruction of spine and vertebra and computed scientifically the three-dimensional geometric characteristics of the vertebra based on the medical theory of spine and vertebra by using the computer visualization technology.It mainly includes:1. The reconstruction of the 3D model. Firstly, it achieved images restoration by using median filter for the two-dimensional CT images of the vertebra, and then completed the three-dimensional reconstruction of the vertebra by using VTK and OpenGL. It used marching cubes (MC) algorithm to implement the surface rendering of the vertebra, as well as ray-casting algorithm for the volume rendering.2. The simplification of triangular mesh model. More triangles should be stored after the 3D reconstruction, which affect the display and calculation of the model. Based on the analysis of existing algorithm, a new mesh simplification algorithm based on discrete curvature is proposed. Experimental results show that this algorithm is significantly simplified and the characteristics of the details are maintained.3. 3D measurement technology. Firstly, it presented technologies as three-dimension interactive observation, rotation and picking. Also, it realized the picking of three-dimensional points. Focus on the vertebra geometric character, a new method in calculating the sectional area is proposed, which was verified to be practical through experiments. Furthermore, it provided the methods in calculating the distance, angles, sectional area, volume, and accomplished 3D measurement of the vertebra model. 4. The design and implementation of the 3D reconstruction and measurement system "SpineEditor". The function of SpineEditor consists of the inputting and preprocessing of the data, contour extract and simplification, 3D reconstruction, triangle mesh simplification, 3D model display, 3D interaction, 3D measurement and so on.This research work is supported by National Natural Science Foundation of China "Research on Three Dimension Statistic Geometrical Shape Models of the Spine and vertebrae" (No.60871097).