DeBakey Heart and Vascular Center, Houston Methodist Hospital, Houston, Tex.
Department of Mechanical Engineering, Rice University, Houston, Tex.
J Vasc Surg. 2018 Apr;67(4):1274-1281. doi: 10.1016/j.jvs.2017.01.072. Epub 2017 Jun 2.
Combining three-dimensional (3D) catheter control with electromagnetic (EM) tracking-based navigation significantly reduced fluoroscopy time and improved robotic catheter movement quality in a previous in vitro pilot study. The aim of this study was to expound on previous results and to expand the value of EM tracking with a novel feature, assistednavigation, allowing automatic catheter orientation and semiautomatic vessel cannulation.
Eighteen users navigated a robotic catheter in an aortic aneurysm phantom using an EM guidewire and a modified 9F robotic catheter with EM sensors at the tip of both leader and sheath. All users cannulated two targets, the left renal artery and posterior gate, using four visualization modes: (1) Standard fluoroscopy (control). (2) 2D biplane fluoroscopy showing real-time virtual catheter localization and orientation from EM tracking. (3) 2D biplane fluoroscopy with novel EM assisted navigation allowing the user to define the target vessel. The robotic catheter orients itself automatically toward the target; the user then only needs to advance the guidewire following this predefined optimized path to catheterize the vessel. Then, while advancing the catheter over the wire, the assisted navigation automatically modifies catheter bending and rotation in order to ensure smooth progression, avoiding loss of wire access. (4) Virtual 3D representation of the phantom showing real-time virtual catheter localization and orientation. Standard fluoroscopy was always available; cannulation and fluoroscopy times were noted for every mode and target cannulation. Quality of catheter movement was assessed by measuring the number of submovements of the catheter using the 3D coordinates of the EM sensors. A t-test was used to compare the standard fluoroscopy mode against EM tracking modes.
EM tracking significantly reduced the mean fluoroscopy time (P < .001) and the number of submovements (P < .02) for both cannulation tasks. For the posterior gate, mean cannulation time was also significantly reduced when using EM tracking (P < .001). The use of novel EM assisted navigation feature (mode 3) showed further reduced cannulation time for the posterior gate (P = .002) and improved quality of catheter movement for the left renal artery cannulation (P = .021).
These results confirmed the findings of a prior study that highlighted the value of combining 3D robotic catheter control and 3D navigation to improve safety and efficiency of endovascular procedures. The novel EM assisted navigation feature augments the robotic master/slave concept with automated catheter orientation toward the target and shows promising results in reducing procedure time and improving catheter motion quality.
在之前的一项体外试验研究中，将三维（3D）导管控制与基于电磁（EM）跟踪的导航相结合，显著减少了透视时间并提高了机器人导管的运动质量。本研究旨在进一步阐述先前的结果，并通过一种新的功能——辅助导航，来扩展 EM 跟踪的价值，该功能允许自动导管定向和半自动血管插管。
18 名使用者使用 EM 导丝和经改良的带有 EM 传感器的 9F 机器人导管对主动脉瘤模型中的机器人导管进行导航，传感器位于导管头端的导丝和鞘管上。所有使用者均使用四种可视化模式对两个靶标，即左肾动脉和后腔门进行插管：（1）标准透视（对照）。（2）二维双平面透视，实时显示 EM 跟踪的虚拟导管定位和定向。（3）二维双平面透视与新型 EM 辅助导航，允许使用者定义目标血管。机器人导管自动朝向目标定向；然后，使用者只需沿此预定义的优化路径推进导丝即可插管血管。接着，在导丝上推进导管的同时，辅助导航会自动修改导管的弯曲和旋转，以确保顺利进行，避免导丝丢失。（4）显示实时虚拟导管定位和定向的虚拟 3D 模型。始终提供标准透视；记录每种模式和目标插管的透视时间和插管时间。使用 EM 传感器的 3D 坐标测量导管的微运动次数来评估导管运动质量。使用 t 检验比较标准透视模式与 EM 跟踪模式。
EM 跟踪显著减少了两个插管任务的平均透视时间（P<0.001）和导管微运动次数（P<0.02）。对于后腔门，EM 跟踪也显著减少了平均插管时间（P<0.001）。新型 EM 辅助导航功能（模式 3）进一步减少了后腔门的插管时间（P=0.002），并提高了左肾动脉插管的导管运动质量（P=0.021）。
这些结果证实了先前研究的发现，即强调将 3D 机器人导管控制与 3D 导航相结合，以提高血管内手术的安全性和效率。新型 EM 辅助导航功能通过自动将导管定向到目标来增强机器人主从控制概念，并在减少手术时间和提高导管运动质量方面显示出有希望的结果。
