Abstract:
We developed two methods for three-dimensional (3D) evaluation of spinal alignment in standing position by image matching between biplanar x-ray images and 3D vertebral models. One used a Slot-Scanning 3D x-ray Imager (sterEOS) to obtain biplanar x-ray images, and the other used a conventional x-ray system and a rotating table. The 3D vertebral model was constructed from the CT scan data. The spatial position of the vertebral model was determined by minimizing the contour difference between the projected image of the model and the biplanar x-ray images. Verification experiments were conducted using a torso phantom. The relative positions of the upper vertebrae to the lowest vertebrae of the cervical, thoracic, and lumbar vertebrae were evaluated. The mean, standard deviation, and mean square error of the relative position were less than 1° and 1 mm in all cases for sterEOS. The maximum mean squared errors of the conventional x-ray system and the rotating table were 0.7° and 0.4 mm for the cervical spine, 1.0° and 1.2 mm for the thoracic spine, and 1.1° and 1.2 mm for the lumbar spine. Therefore, both methods could be useful for evaluating the spinal alignment in standing position.
摘要:
我们开发了两种方法,通过双平面X射线图像和3D椎骨模型之间的图像匹配,对站立姿势的脊柱对准进行三维(3D)评估。一个人使用狭缝扫描3DX射线成像仪(sterEOS)来获得双平面X射线图像,另一个使用传统的x光系统和旋转台。从CT扫描数据构建3D椎体模型。通过最小化模型的投影图像与双平面X射线图像之间的轮廓差异来确定椎骨模型的空间位置。使用躯干体模进行验证实验。上椎骨与颈椎最低椎骨的相对位置,胸廓,和腰椎进行评估。意思是,标准偏差,在所有情况下,相对位置的均方误差均小于1°和1mm。常规x射线系统和旋转台的最大均方误差分别为颈椎0.7°和0.4mm,胸椎为1.0°和1.2mm,和1.1°和1.2毫米的腰椎。因此,这两种方法都可用于评估站立位置的脊柱排列。