Zeng Bowei, Meng Fanle, Ding Hui, Wang Guangzhi
Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, People's Republic of China.
Int J Comput Assist Radiol Surg. 2017 Aug;12(8):1355-1368. doi: 10.1007/s11548-017-1634-1. Epub 2017 Jun 29.
Using existing stereoelectroencephalography (SEEG) electrode implantation surgical robot systems, it is difficult to intuitively validate registration accuracy and display the electrode entry points (EPs) and the anatomical structure around the electrode trajectories in the patient space to the surgeon. This paper proposes a prototype system that can realize video see-through augmented reality (VAR) and spatial augmented reality (SAR) for SEEG implantation. The system helps the surgeon quickly and intuitively confirm the registration accuracy, locate EPs and visualize the internal anatomical structure in the image space and patient space.
We designed and developed a projector-camera system (PCS) attached to the distal flange of a robot arm. First, system calibration is performed. Second, the PCS is used to obtain the point clouds of the surface of the patient's head, which are utilized for patient-to-image registration. Finally, VAR is produced by merging the real-time video of the patient and the preoperative three-dimensional (3D) operational planning model. In addition, SAR is implemented by projecting the planning electrode trajectories and local anatomical structure onto the patient's scalp.
The error of registration, the electrode EPs and the target points are evaluated on a phantom. The fiducial registration error is [Formula: see text] mm (max 1.22 mm), and the target registration error is [Formula: see text] mm (max 1.18 mm). The projection overlay error is [Formula: see text] mm, and the TP error after the pre-warped projection is [Formula: see text] mm. The TP error caused by a surgeon's viewpoint deviation is also evaluated.
The presented system can help surgeons quickly verify registration accuracy during SEEG procedures and can provide accurate EP locations and internal structural information to the surgeon. With more intuitive surgical information, the surgeon may have more confidence and be able to perform surgeries with better outcomes.
使用现有的立体定向脑电图(SEEG)电极植入手术机器人系统,难以直观地验证配准精度并向外科医生展示患者空间中电极入点(EP)以及电极轨迹周围的解剖结构。本文提出了一种用于SEEG植入的能够实现视频透视增强现实(VAR)和空间增强现实(SAR)的原型系统。该系统帮助外科医生快速直观地确认配准精度、定位EP,并在图像空间和患者空间中可视化内部解剖结构。
我们设计并开发了一种附着在机器人手臂远端法兰上的投影相机系统(PCS)。首先,进行系统校准。其次,使用PCS获取患者头部表面的点云,用于患者到图像的配准。最后,通过合并患者的实时视频和术前三维(3D)手术规划模型来生成VAR。此外,通过将规划电极轨迹和局部解剖结构投影到患者头皮上来实现SAR。
在体模上评估配准误差、电极EP和目标点。基准配准误差为[公式:见原文]毫米(最大1.22毫米),目标配准误差为[公式:见原文]毫米(最大1.18毫米)。投影叠加误差为[公式:见原文]毫米,预变形投影后的TP误差为[公式:见原文]毫米。还评估了外科医生视点偏差引起的TP误差。
所提出的系统可以帮助外科医生在SEEG手术过程中快速验证配准精度,并能为外科医生提供准确的EP位置和内部结构信息。有了更直观的手术信息,外科医生可能会更有信心,从而能够获得更好的手术效果。