Graduate School of Engineering, Kobe University, Japan.
Med Image Anal. 2012 Feb;16(2):415-26. doi: 10.1016/j.media.2011.10.005. Epub 2011 Nov 7.
Atlas-based methods for automated preoperative planning of the femoral stem implant in total hip arthroplasty are described. Statistical atlases are constructed from a number of past preoperative plans prepared by experienced surgeons in order to represent the surgeon's expertise of the planning. Two types of atlases are considered. One is a statistical distance map atlas, which represents surgeon's preference of the contact pattern between the femoral canal (host bone) and stem (implant) surfaces. The other is an optimal reference plan, which is selected as the best representative plan expected to minimize the deviation from the surgeon's preferred contact pattern. These atlases are fitted to the patient data to automatically generate the preoperative plan of the femoral stem. In this paper, we formulate a general framework of atlas-based implant planning, and then describe the methods for construction and utilization of the two proposed atlases. In the experiments, we used 40 cases to evaluate the proposed methods and compare them with previous methods by defining the errors as differences between automated and surgeon's plans. By using the proposed methods, the positional and orientation errors were significantly reduced compared with the previous methods and the size error was superior to inter-surgeon variability in size selection using 2D templates on an X-ray image reported in previous work.
描述了基于图谱的全髋关节置换术股骨柄植入物术前自动规划方法。统计图谱是由许多有经验的外科医生术前准备的计划构建而成，以代表外科医生的规划专业知识。考虑了两种类型的图谱。一种是统计距离图图谱，它代表了外科医生对股骨髓腔（宿主骨）和柄（植入物）表面之间接触模式的偏好。另一种是最佳参考计划，它被选为最能最小化与外科医生首选接触模式偏差的最佳代表计划。这些图谱被拟合到患者数据中，以自动生成股骨柄的术前计划。在本文中，我们提出了一个基于图谱的植入物规划的通用框架，然后描述了构建和利用这两种建议图谱的方法。在实验中，我们使用了 40 个病例来评估所提出的方法，并通过将自动规划和外科医生规划之间的差异定义为误差，与以前的方法进行了比较。与以前的方法相比，使用所提出的方法显著降低了位置和方向误差，并且在 X 射线图像上使用 2D 模板进行大小选择的外科医生之间的变异方面优于大小误差。
