Wang Lejing, Traub Joerg, Weidert Simon, Heining Sandro Michael, Euler Ekkehard, Navab Nassir
Chair for Computer Aided Medical Procedures (CAMP), TU Munich, Germany.
Med Image Comput Comput Assist Interv. 2009;12(Pt 1):173-80. doi: 10.1007/978-3-642-04268-3_22.
In this paper, we present a novel method to create parallax-free panoramic X-ray images of long bones during surgery by making the C-arm rotate around its X-ray source, relative to the patient's table. In order to ensure that the C-arm motion is a relative pure rotation around its X-ray source, we move the table to compensate for the translational part of the motion based on C-arm pose estimation, for which we employed a Camera Augmented Mobile C-arm system and a visual planar marker pattern. Thus, we are able to produce a parallax-free panoramic X-ray image that preserves the property of linear perspective projection. We additionally implement a method to reduce the error caused by varying intrinsic parameters of C-arm X-ray imaging. The results show that our proposed method can generate a parallax-free panoramic X-ray image, independent of the configuration of bone structures and without the requirement of a fronto-parallel setup or any overlap in the X-ray images. The resulting panoramic images have a negligible difference (below 2 pixels) in the overlap between two consecutive individual X-ray images and have a high visual quality, which promises suitability for intra-operative clinical applications in orthopedic and trauma surgery.
在本文中，我们提出了一种新颖的方法，通过使C形臂相对于患者手术台绕其X射线源旋转，来创建手术过程中长骨的无视差全景X射线图像。为确保C形臂运动是绕其X射线源的相对纯旋转，我们基于C形臂姿态估计移动手术台以补偿运动的平移部分，为此我们采用了摄像头增强移动C形臂系统和视觉平面标记图案。这样，我们能够生成保留线性透视投影特性的无视差全景X射线图像。我们还实现了一种方法来减少由C形臂X射线成像固有参数变化引起的误差。结果表明，我们提出的方法可以生成无视差全景X射线图像，与骨结构配置无关，并且无需额面平行设置或X射线图像有任何重叠。所得全景图像在两个连续的单独X射线图像之间的重叠部分差异可忽略不计（低于2像素），并且具有很高的视觉质量，这表明适用于骨科和创伤手术的术中临床应用。
