Department of Computer Science II, University of Bonn, Germany.
Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, China.
Comput Med Imaging Graph. 2021 Jun;90:101905. doi: 10.1016/j.compmedimag.2021.101905. Epub 2021 Mar 31.
In recent years, the radiofrequency ablation (RFA) therapy has become a widely accepted minimal invasive treatment for liver tumor patients. However, it is challenging for doctors to precisely and efficiently perform the percutaneous tumor punctures under free-breathing conditions. This is because the traditional RFA is based on the 2D CT Image information, the missing spatial and dynamic information is dependent on surgeons' experience. This paper presents a novel quantitative and intuitive surgical navigation modality for percutaneous respiratory tumor puncture via augmented virtual reality, which is to achieve the augmented visualization of the pre-operative virtual planning information precisely being overlaid on intra-operative surgical scenario. In the pre-operation stage, we first combine the signed distance field of feasible structures (like liver and tumor) where the puncture path can go through and unfeasible structures (like large vessels and ribs) where the needle is not allowed to go through to quantitatively generate the 3D feasible region for percutaneous puncture. Then we design three constraints according to the RFA specialists consensus to automatically determine the optimal puncture trajectory. In the intra-operative stage, we first propose a virtual-real alignment method to precisely superimpose the virtual information on surgical scenario. Then, a user-friendly collaborative holographic interface is designed for real-time 3D respiratory tumor puncture navigation, which can effectively assist surgeons fast and accurately locating the target step-by step. The validation of our system is performed on static abdominal phantom and in vivo beagle dogs with artificial lesion. Experimental results demonstrate that the accuracy of the proposed planning strategy is better than the manual planning sketched by experienced doctors. Besides, the proposed holographic navigation modality can effectively reduce the needle adjustment for precise puncture as well. Our system shows its clinical feasibility to provide the quantitative planning of optimal needle path and intuitive in situ holographic navigation for percutaneous tumor ablation without surgeons' experience-dependence and reduce the times of needle adjustment. The proposed augmented virtual reality navigation system can effectively improve the precision and reliability in percutaneous tumor ablation and has the potential to be used for other surgical navigation tasks.
近年来，射频消融 (RFA) 治疗已成为一种广泛接受的肝肿瘤患者微创治疗方法。然而，在自由呼吸条件下，医生精确有效地进行经皮肿瘤穿刺具有挑战性。这是因为传统的 RFA 基于 2D CT 图像信息，缺失的空间和动态信息依赖于外科医生的经验。本文提出了一种新颖的定量直观的经皮呼吸肿瘤穿刺手术导航方法，通过增强虚拟现实来实现术前虚拟规划信息的精确叠加到手术场景中。在手术前阶段，我们首先结合可行结构（如肝和肿瘤）的有符号距离场和不可行结构（如大血管和肋骨），定量生成用于经皮穿刺的 3D 可行区域。然后，根据 RFA 专家的共识设计了三个约束条件，自动确定最佳穿刺轨迹。在手术阶段，我们首先提出了一种虚拟-现实对齐方法，精确地将虚拟信息叠加到手术场景上。然后，设计了一个用户友好的协作全息界面，用于实时 3D 呼吸肿瘤穿刺导航，可有效地帮助外科医生逐步快速准确地定位目标。我们的系统在静态腹部体模和体内比格犬的人工病变上进行了验证。实验结果表明，所提出的规划策略的准确性优于经验丰富的医生手工绘制的规划。此外，所提出的全息导航方法还可以有效地减少精确穿刺的针调整次数。我们的系统证明了其临床可行性，可提供定量规划的最佳针路径和直观的原位全息导航，无需外科医生的经验依赖性，并减少针调整次数。所提出的增强虚拟现实导航系统可以有效地提高经皮肿瘤消融的精度和可靠性，并有潜力用于其他手术导航任务。
