【作者】 贾永磊；

【导师】 林晓梅；

【作者基本信息】 长春工业大学 ， 测试计量技术及仪器， 2011， 硕士

【摘要】 随着人们生活水平的提高,心脑血管疾病成为了影响人类健康最主要的病因之一,计算可视化技术及医学影像技术的发展,为心脑血管疾病的诊断输入了新的血液,脑血管的提取和可视化,使得医生从传统的诊断方法中脱离出来,不仅仅使医生获得了更丰富的医疗信息,更将人为的误差降低到最小。针对图像中存在的噪声干扰,采用图像平滑算法对图像进行滤波,以此来消除图像中的噪声,平滑图像边缘；针对图像对比度差,采用了对比度增强算法增强了图像对比度；为了方便医生多视角观察切片组织,引入了几何变换算法,为血管提取及三维显示奠定基础。血管轮廓的提取对于血管疾病的研究及血管中轴参数的确定是一个基础,对血管树的三维显示精度起着决定性的作用,纵观现有算法及其优缺点,综合采用了基于区域生长算法及基于Sobel算子的边缘检测算法,用于提取血管边缘轮廓。血管中轴跟原图像具有相同拓扑性和相似的几何形状,因此能较好的反映血管的走向及空间结构,同时可以有效的佐证血管轮廓的提取的准确性。针对血管造影图像自身对比度差及背景复杂等缺陷,本文采用了多尺度Gabor变换算法提取血管中轴,在增强血管中轴的同时有效抑制图像噪声,通过调节方位带宽和频率得到最大响应图像,对响应图进行非极大值抑制,并通过阈值分割求出血管中轴。利用三维重建技术,将提取后的血管图像进行三维还原,本文采用改进的移动立方体法(简称MC算法)进行血管的三维绘制,绘制结果表面平滑,没有空洞,达到了理想的效果。更多还原

【Abstract】 With the improving of the life of the people, cardiovascular and cerebrovascular diseases become one main cause of disease which affect human health, the development of the computer graphics and visualization and the medical imaging join the new blood to the diagnosis of the cardiovascular and cerebrovascular diseases. The extraction and visualization of the Cerebral hemorrhage,which provide more medical information and less error, freed the doctor from the traditional diagnostic method.In view of the noise in the data, smoothing filter is used to remove the noise and contrast enhancement is used to enhancement the contrast of the image, however, the geometric transformation algorithm are designed to provide the multi-angle of view for the medical worker, it set the stage for the extraction and the visualization of the blood.The extraction of the blood edge,which play a critical part on the 3D reconstruction, lay the root for the research of the cerebrovascular and seeking for the parameter of the blood center shaft. In this thesis more algorithms were weighted, region growing algorithm and edge detection based on Sobel operator are used to detection the edge of the cerebrovascular.The vessel axis can reflect well of the vessel direction and the space structure because of it having the same topology and geometrical, however, it can proved the efficiency of the vessel extraction.Multiple scales Gabor filter is used to extract the vessel axis owing to the complicated background and lower contrast of the angiography images, the vessel axis is enhanced while the noise is moved, we can get the maximal response diagram by adjusting the orientation bandwidth and the frequency bandwidth, after that, non-maximal rejection algorithm and threshold segmentation algorithm are adopted to detection the vessel axis.3D reconstruct technology is used to restore the 3D structure of the extracted vessels. The improved moving cubes algorithm is (MC algorithm in short) adopted to plot the 3D vessels and the surface are smoothness without the hole as expected.更多还原