Objective: Two-dimensional fluoroscopy is the standard guidance imaging method for closed endovascular intervention. However, two-dimensional fluoroscopy lacks depth perception for the intervention catheter and causes radiation exposure for both surgeons and patients. In this paper, we extend our previous study and develop the improved three-dimensional (3D) catheter shape estimation using ultrasound imaging. In addition, we perform further quantitative evaluations of endovascular navigation. Method: First, the catheter tracking accuracy in ultrasound images is improved by adjusting the state vector and adding direction information. Then, the 3D catheter points from the catheter tracking are further optimized based on the 3D catheter shape optimization with a high-quality sample set. Finally, the estimated 3D catheter shapes from ultrasound images are overlaid with preoperative 3D tissue structures for the intuitive endovascular navigation. Results: the tracking accuracy of the catheter increased by 24.39%, and the accuracy of the catheter shape optimization step also increased by approximately 17.34% compared with our previous study. Furthermore, the overall error of catheter shape estimation was further validated in the catheter intervention experiment of in vitro cardiovascular tissue and in a vivo swine, and the errors were 2.13 mm and 3.37 mm, respectively. Conclusion: Experimental results demonstrate that the improved catheter shape estimation using ultrasound imaging is accurate and appropriate for endovascular navigation. Significance: Improved navigation reduces the radiation risk because it decreases use of X-ray imaging. In addition, this navigation method can also provide accurate 3D catheter shape information for endovascular surgery.

中文翻译：

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改进的3D导管形状估计使用超声成像的血管内导航：进一步的研究。

目的：二维荧光透视是封闭血管内介入治疗的标准指导成像方法。然而，二维荧光透视术缺乏对介入导管的深度感知，并且导致外科医生和患者都暴露于放射线。在本文中，我们扩展了先前的研究并开发了使用超声成像的改进的三维（3D）导管形状估计。此外，我们进行血管内导航的进一步定量评估。方法：首先，通过调整状态向量和添加方向信息来提高超声图像中的导管跟踪精度。然后，基于具有高质量样本集的3D导管形状优化，进一步优化来自导管跟踪的3D导管点。最后，将超声图像估计的3D导管形状与术前3D组织结构重叠，以进行直观的血管内导航。结果：与我们以前的研究相比，导管的跟踪精度提高了24.39％，导管形状优化步骤的精度也提高了约17.34％。此外，在体外心血管组织和体内猪的导管干预实验中，进一步验证了导管形状估计的总体误差，误差分别为2.13 mm和3.37 mm。结论： 实验结果表明，使用超声成像改进的导管形状估计是准确的，适用于血管内导航。 意义：改进的导航降低了辐射风险，因为它减少了X射线成像的使用。此外，这种导航方法还可以为血管内手术提供准确的3D导管形状信息。