Needle insertion is commonly performed in minimally invasive medical procedures such as biopsy and radiation cancer treatment. During such procedures, accurate needle tip placement is critical for correct diagnosis or successful treatment. Accurate placement of the needle tip inside tissue is challenging, especially when the target moves and anatomical obstacles must be avoided. We develop a needle steering system capable of autonomously and accurately guiding a steerable needle using two-dimensional (2D) ultrasound images. The needle is steered to a moving target while avoiding moving obstacles in a three-dimensional (3D) non-static environment. Using a 2D ultrasound imaging device, our system accurately tracks the needle tip motion in 3D space in order to estimate the tip pose. The needle tip pose is used by a rapidly exploring random tree-based motion planner to compute a feasible needle path to the target. The motion planner is sufficiently fast such that replanning can be performed repeatedly in a closed-loop manner. This enables the system to correct for perturbations in needle motion, and movement in obstacle and target locations. Our needle steering experiments in a soft-tissue phantom achieves maximum targeting errors of 0.86 ± 0.35 mm (without obstacles) and 2.16 ± 0.88 mm (with a moving obstacle).

中文翻译：

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三维非静态环境中使用二维超声图像的针路径规划和转向

针插入通常在微创医疗程序中进行，例如活检和放射癌治疗。在此类程序中，准确的针尖位置对于正确诊断或成功治疗至关重要。将针尖准确放置在组织内具有挑战性，尤其是在目标移动且必须避免解剖障碍时。我们开发了一种针转向系统，能够使用二维 (2D) 超声图像自主准确地引导可转向针。在 3D (3D) 非静态环境中，将指针转向移动目标，同时避开移动障碍物。使用 2D 超声成像设备，我们的系统可以准确地跟踪 3D 空间中的针尖运动，以估计针尖姿势。针尖姿势由快速探索的基于随机树的运动规划器使用来计算到目标的可行针路径。运动规划器足够快，因此可以以闭环方式重复执行重新规划。这使系统能够校正指针运动中的扰动以及障碍物和目标位置的运动。我们在软组织模型中的针转向实验实现了 0.86 ± 0.35 毫米（无障碍物）和 2.16 ± 0.88 毫米（有移动障碍物）的最大瞄准误差。