【摘要】 目的　实现计算机手术模拟中的三维骨组织分割 ,即在计算机上模拟外科手术中的截骨 ,并使之能实际应用于计算机手术模拟系统中 .方法　用患者的 CT图像作为原始数据进行三维重构与显示 .在三维显示图像上进行三维截骨 .本文定义了实物坐标系与显示坐标系 .实物坐标系经过一系列变换通过三维显示的二维投影面与显示坐标系统一 .以统一的二维投影面作为交互平台确定分割平面 .基于微分的思想将分割面离散成一条条直线 ,求每条直线与三维数据的交点 ,从而确定分割边缘 ,实现三维体数据的分割 .结果　对2 5 6× 2 5 6× 94的 CT图像数据用两种算法进行三维重构的图像进行三维截骨 ,实验表明用该方法成功实现了三维截骨 .两种重构方法截骨响应时间相同 .截骨响应时间依据截骨骨块体积大小的不同和计算机硬件性能的差别有所不同 .本文所用计算机硬件能满足颅颌面整形外科手术模拟系统的需要 .结论　本方法兼顾了截骨的准确性和计算机的动态响应速度 ,用于颅颌面整形外科手术模拟系统中的结果证明了其正确性与实用性更多还原

【Abstract】 AIM To complete 3D bone images segmentation in co mputer operation simulation system and to make it fast enough to be used in computer operation simulation system. METHODS 3D medical images were reconstructed from patient series of t wo-dimensional images produced by computerized tomography. Direct 3D bone image segmentation was done in 3D display images. World coordinate and disp lay coordinate are defined in the paper. World coordinate that had undergone some transform such as translatio n, and rotation was unified with display coordinate through 2D projection plane of 3D display coordinate. We regarded the 2D projection plane as an interactive plane to ascertain the area of the cut bone. According to the idea o f differential we the cut bone area we (decomposedinto) discrete lines. By calcu lating the cross points of the every discrete line and 3D data, we got the edge of the area of the cut bone, and the 3D volume data were thus segmented. RESULTS 3D display images reconstructed by two algorithm from 256×256×94 two-dimensional CT data were s egmented. The results showed 3D osteotomy could realized rapidly. The osteotomy time consume of computer is the same when either of two reconstruction methods was used. The time be varied with computer hardware and t he volume of desired bone. The hardware in the paper is applicable to the Oral Maxillofacial Surgery Simulation System. CONCLUSION The method concerns both osteotomy precision and computer time consumption. The result of the method used in oral and maxillofacial surgery simulation has proved its ava ilability.更多还原