自由变形算法在快速骨重建中的应用  

Application of Free-form Deformation Algorithm in Fast Three-dimensioanl Bone Reconstruction

作　　者：曾祥森[1,2] 周海[1] 王成焘[1] 王冬梅[1] 陈功 

机构地区：[1]上海交通大学生物医学制造与生命质量研究所,上海200240 [2]上海市第一人民医院,上海200080 [3]昆山阔福门业有限公司,昆山215301

出　　处：《生物医学工程学杂志》2014年第5期1121-1126,共6页Journal of Biomedical Engineering

基　　金：973计划资助项目(2011BC711000);国家自然科学基金资助项目(51375304)

摘　　要：本文在传统自由变形算法的基础上,提出了一种应用在人体骨骼快速三维重建的单位自由变形(FFD)算法。文中以股骨为例,依据单位自由变形算法实现利用两张X线片对股骨进行快速三维模型重建的工作。利用专业C臂机上获取两张正交方向拍摄的X线片,并保留拍摄参数;借助X线片提供的轮廓信息对标准模型进行个性化三维重建。文中通过点配对算法建立了X线片外轮廓与三维标准模型外轮廓之间的对应关系,将传统自由变形算法进行简化设计,利用单位自由变形控制格对标准模型进行重建,最终使得X线片外轮廓与标准模型外轮廓一致,从而获得个性化的股骨三维模型。选取35例尸体股骨样本设计外形精度、鲁棒性和重建速度实验,最终得到全骨的二维点配对平均时间为20s,平均重建时间为112s;三维模型的外形平均误差为0.52mm,且精度和速度均保持稳定,具有良好的鲁棒性。本研究将传统自由变形算法简化应用到重建模型算法中,使得重建时间减少,重建精度达到传统方法要求,同时具备良好的可重复性,在临床应用和相关科学研究中具有很好的应用前景。This paper presents a unit free-form deformation（FFD）method applied to rapid three-dimensioanl（3D）bone reconstruction,which was based on traditional FFD.With the femur as an example,we reconstructed a 3D model of femur from two X-ray images and a standardized model by taking advantage of unit FFD algorithm.The Xray images and its parameters were taken by C-arm device.Those parameters and X-ray contour are contributed to3 Dreconstruction.The out contours of X-ray image and standard model were connected by point matching algorithm.The unit-FFD lattice was built to reconstruct standard model and finally made the contour of X-ray image and standard model exactly the same.Experiments on shape accuracy,robustness and time consuming,carried out by 35 specimen from cadaver,showed that mean error of shape（0.52mm）and mean construction time（112s）were lower than those using traditional method（0.7-2.6mm,8-20min）.The method proposed in this paper shows a good prospect in clinical application and related research.

关 键 词：X线片 点配对算法 自由变形算法 三维重建 股骨标准模型 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]