摘要
脑肿瘤发病率逐日升高，是严重危害人类生命健康的重大疾病之一。随着各种新的医学成像技术的临床应用，脑肿瘤诊断和治疗技术取得了很大的进展，CT、MRI检查是其有效常用的手段。
不同的图像模态能够提供不同的信息，多模态医学图像处理是一个较新的研究领域，涉及多领域的知识，需要医学专家的指导，具有人机结合的特色。包括：医学影像数据获取、医学图像分割、配准、融合、三维可视化等。
医学数据的可视化，已成为数据可视化领域中最为活跃的研究领域之一。医学图像三维重建及可视化在诊断医学、手术规划及模拟仿真以及放疗计划等方面都有重要应用。
本文针对脑肿瘤的不同影像图像进行研究，首先采用奇异值分解方法将密度分辨率最高、显示骨质结构和钙化最佳的CT图像与软组织对比分辨率最高的MRI图像进行配准，然后是利用模糊C均值(FCM)算法对融合后的图像进行分割与标注，最后用Marching Cubes算法对图像进行了三维重建，初步开发了一个医学图像可视化研究系统雏形，在PC机上实现了医学图像的匹配、融合、分割和三维重建以及多种方式的输出。
本文的研究是初步的，尚未对匹配、分割、三维重建结果进行定量的评价，但将为进一步研究适用于微机的可视化算法和软硬件平台打下基础。
As one of the serious diseases threatening the health of human being, the brain tumor has an increasing incidence. Owing to the application of some new imaging techniques to clinic, great achievements have been done in the diagnosis and treatment of the brain tumor. At present CT and MRI are the common uses in medical imaging.
The processing of medical images with multi-modality is a new research field, which involves the knowledge of a lot of variable scientific fields, needing the guidance of the medical experts and having the features of the combination of the man and machine. Its regiment includes medical images' data access, registration, fusion, segmentation and three-dimensional visualization.
The visualization of medical data has been one of the most vigorous fields in the data visualization. Visualization of medical images is widely used in diagnostic, surgical planning and simulating, and radiotherapy planning.
The brain tumor is our object for research. First, single value decomposition is used to register CT and MRI images. Second, fuzzy c means (FCM) method is adopted for segmentation. Last, Marching cube (MC) algorithm is applied to reconstruction of the image.
An elementary visualization system is achieved through our work. We can exercise registration, fusion, segmentation and three-dimensional reconstruction of the medical images in personal computer.
Although our study is premature with the lack of quantitative assessment of the result, the paper can lay a foundation to the further research for visualization algorithm and system platform which is appropriate to personal computer.
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