基于双平面DR的骨折股骨三维姿态估计  

3D pose estimation of fracture femur based on bi-planar digital radiographs

作　　者：张斌[1,2] 孙金玮[1] 孙绍滨[1] 

机构地区：[1]哈尔滨工业大学自动化测试与控制系,哈尔滨150001 [2]哈尔滨理工大学电子信息工程系,哈尔滨150080

出　　处：《仪器仪表学报》2013年第1期140-146,共7页Chinese Journal of Scientific Instrument

基　　金：黑龙江省自然科学基金(QC2010062);哈尔滨市科技创新人才研究专项资金(2011RFQXS086)资助项目

摘　　要：针对骨折股骨DR缺少三维模态下空间信息的问题,提出一种基于双平面DR进行2D-3D非刚性配准的姿态估计方法,实现骨外科手术术前骨折股骨的三维可视化。本文提出的方法相比于单纯的DR或CT成像诊断方式,具有成本低、成像快、有害辐射小、精度高等优点。该方法首先利用正、侧位骨折股骨DR获得与通用模型投影轮廓的二维配准参数;然后利用基于针孔相机模型的标定法确定二维平面到三维空间的变换关系,最后将通用模型分成骨折的两段,确定每段的姿态,获得患者股骨个体化骨折姿态。实验结果为平均旋转误差小于1.5°,平均平移误差小于2 mm,配准成功率大于90%,表明该方法具有较高的精度和鲁棒性,可为骨外科手术的术前诊断及手术计划制定提供更为有效的三维影像信息。Aiming at the problem that the digital radiography of fracture femur lacks space information in 3D modali- ty, a pose estimation method based on 2D-3D non-rigid registration using biplanar digital radiographs is proposed to realize preoperative 3D pose visualization of fracture femur model. Compared with simple DR or CT diagnosis meth- ods, the proposed method has the advantages of low cost, fast imaging speed, little radiation to the patients and high precision. Firstly, the 2D registration parameters between the projected contours of generic model and DR image contours of fracture femur from frontal and lateral views are obtained. Secondly, the transform relationship from 2D plane to 3 D space is determined by using the calibration method based on pinhole camera model. Finally, the generic model is divided into two fracture parts and the pose of each part is determined. Then the individual fracture pos- ture of patient femur is acquired. Experiment results indicate that the proposed method possesses high precision and good robustness ; the average rotation and translation errors are less than 1.5 - and 2 mm, respectively, and the registration success rate is greater than 90%. The proposed method can provide more effective 3D image information for the preoperative orthopaedic diagnosis and surgery planning.

关 键 词：数字X光片 仿射ICP算法 2D-3D配准 姿态估计 外科手术术前诊断 

分 类 号：TP391.7[自动化与计算机技术—计算机应用技术] TH79[自动化与计算机技术—计算机科学与技术]