首先介绍了医学图像三维重建的面绘制与体绘制方法，讨论了两种绘制方法的思想和优缺点，对常用的Marching Cubes算法和Ray Casting算法的原理和实现过程进行了阐述，并分析了可视化工具包VTK的实现机制。在VC++6．0平台下，结合可视化工具包VTK，分别基于Marching Cubes算法和Ray Casting算法对DICOM格式的CT图像序列进行三维重建，并给出了其实现的关键算法和3D可视化结果。通过人机交互，实现对重建后三维医学图像的旋转、缩放、平移等简单的交互操作。其次，通过设置虚拟切面的法向量和内点来对重建后的三维物体进行切割并获得断面信息，并且在切割的同时可以同步显示出断面图像，进而实现了三维医学图像的任意角度断面图像提取；构造可控制的长方体，可以用鼠标控制长方体进行拉伸、缩放、平移、旋转等操作来对重建对象进行切割，实现用户对三维物体的实时交互切割；在三维空间中通过点击鼠标来获得空间点的三维坐标，实现三维空间中点的鼠标拾取，完成三维物体的空间定量测量。最终，实现对重建后三维医学图像的鼠标拾取、空间角度和距离的测量、平面切割、长方体交互切割、任意角度断面图像提取等交互操作。-Firstly，the realization and principle of Marching Cubes and Ray Casting for 3D medical image reconstruction with surface rendering and volume rendering ale discussed and　contrasted in this paper．The excellence and shortage of the two rendering methods ale discussed．And the realization mechanism of visualization tool package based on VTK is analyzed．In the paper,Marching Cubes and Ray Casting algorithm ale respectively adopted to reconstruct the 3D images for the CT image sequence of the DICOM format under the VC++6.0 and the visual package VTK platform．The key algorithms and 3D visualization results are given in this paper．The simple interactive operations，such as rotation，zoom and transfer Can be realized by user interaction with PC．Secondly，the vector and inner points ale calculated to form the virtual clipping plane，which in turn is used to incise the 3D object。And the information of cross—section images is obtained，at the same time the correspondent images are displayed on the scr