Liu Wen Pei, Otake Yoshito, Azizian Mahdi, Wagner Oliver J, Sorger Jonathan M, Armand Mehran, Taylor Russell H
Department of Computer Science, Johns Hopkins University, Baltimore, MD, USA,
Int J Comput Assist Radiol Surg. 2015 Aug;10(8):1239-52. doi: 10.1007/s11548-014-1132-7. Epub 2014 Dec 12.
C-arm radiographs are commonly used for intraoperative image guidance in surgical interventions. Fluoroscopy is a cost-effective real-time modality, although image quality can vary greatly depending on the target anatomy. Cone-beam computed tomography (CBCT) scans are sometimes available, so 2D-3D registration is needed for intra-procedural guidance. C-arm radiographs were registered to CBCT scans and used for 3D localization of peritumor fiducials during a minimally invasive thoracic intervention with a da Vinci Si robot.
Intensity-based 2D-3D registration of intraoperative radiographs to CBCT was performed. The feasible range of X-ray projections achievable by a C-arm positioned around a da Vinci Si surgical robot, configured for robotic wedge resection, was determined using phantom models. Experiments were conducted on synthetic phantoms and animals imaged with an OEC 9600 and a Siemens Artis zeego, representing the spectrum of different C-arm systems currently available for clinical use.
The image guidance workflow was feasible using either an optically tracked OEC 9600 or a Siemens Artis zeego C-arm, resulting in an angular difference of Δθ:∼ 30°. The two C-arm systems provided TRE mean ≤ 2.5 mm and TRE mean ≤ 2.0 mm, respectively (i.e., comparable to standard clinical intraoperative navigation systems).
C-arm 3D localization from dual 2D-3D registered radiographs was feasible and applicable for intraoperative image guidance during da Vinci robotic thoracic interventions using the proposed workflow. Tissue deformation and in vivo experiments are required before clinical evaluation of this system.
C形臂X线片常用于手术干预中的术中图像引导。荧光透视是一种具有成本效益的实时成像方式，尽管图像质量会因目标解剖结构的不同而有很大差异。有时可获得锥形束计算机断层扫描（CBCT），因此在手术过程中需要进行二维-三维配准以提供引导。在使用达芬奇Si机器人进行的微创胸科手术中，将C形臂X线片与CBCT扫描进行配准，并用于肿瘤周围基准点的三维定位。
对术中X线片与CBCT进行基于强度的二维-三维配准。使用体模模型确定围绕配置用于机器人楔形切除术的达芬奇Si手术机器人放置的C形臂可实现的X线投影可行范围。在使用OEC 9600和西门子Artis zeego成像的合成体模和动物上进行实验，这两种设备代表了目前临床可用的不同C形臂系统的范围。
使用光学跟踪的OEC 9600或西门子Artis zeego C形臂，图像引导工作流程是可行的，角度差Δθ约为30°。这两种C形臂系统的平均配准误差（TRE）分别≤2.5 mm和≤2.0 mm（即与标准临床术中导航系统相当）。
使用所提出的工作流程，通过双重二维-三维配准的X线片进行C形臂三维定位对于达芬奇机器人胸科手术中的术中图像引导是可行且适用的。在对该系统进行临床评估之前，需要进行组织变形和体内实验。
