C形臂透视影像的手术引导系统

A Surgical Navigation System Based on C-arm Fluoroscopy Images

研究开发了一种基于校准靶的C形臂X线影像的手术引导系统。系统通过提取分布在校准靶双层模板上的标志点影像,利用标志点特定的分布,提出了确定对应关系的算法,建立了不同坐标系之间标志点中心坐标的联系。基于校准靶影像,校正C形臂X线影像的失真,对C形臂相机模型进行校准。确定C形臂投影模型参数后,术前预先获得病患部位透视影像,术中通过光学定位系统实时跟踪手术工具,在术前影像上形成工具的虚拟投影,引导医生进行手术,从而减少C形臂的使用次数,降低了X线辐射剂量。脊柱标本实验和误差分析表明该系统在临床有一定的使用价值。

A surgical navigation system based on X-rays of C-arm with a calibration target has been studied and developed. Extracting images of markers in the two templates on the calibration target, the system is able to establish the relationship between different markers coordinates in different coordinate systems using the algorithm based on the layout of specific markers. The correction of X-ray image distortion and C-arm camera calibration are performed using the images of calibration target as bases. After the parameters of the C-arm projection model being de-termined, an X-ray image of surgical site will be acquired preoperatively; the surgical instruments will be tracked by the optical position system, and then virtual projections of instruments can be formed on preoperative images. Surgeons will perform operations with the guidance of the system. The C-arm can be used less frequently and the X-ray radiation can be reduced. Cadaveric spine specimen experiments and error analysis have underpinned the clinical feasibility of the system.