van de Berg Nick J, Dankelman Jenny, van den Dobbelsteen John J
Department of Biomechanical Engineering, Delft University of Technology, Faculty of Mechanical, Maritime and Materials Engineering, Mekelweg 2, Delft 2628CD, The Netherlands.
Department of Biomechanical Engineering, Delft University of Technology, Faculty of Mechanical, Maritime and Materials Engineering, Mekelweg 2, Delft 2628CD, The Netherlands.
J Vasc Interv Radiol. 2017 Feb;28(2):276-283.e2. doi: 10.1016/j.jvir.2016.07.018. Epub 2016 Oct 6.
To study the ability of a human operator to manually correct for errors in the needle insertion path without partial withdrawal of the needle by means of an active, tip-articulated steerable needle.
The needle is composed of a 1.32-mm outer-diameter cannula, with a flexure joint near the tip, and a retractable stylet. The bending stiffness of the needle resembles that of a 20-gauge hypodermic needle. The needle functionality was evaluated in manual insertions by steering to predefined targets and a lateral displacement of 20 mm from the straight insertion line. Steering tasks were conducted in 5 directions and 2 tissue simulants under image guidance from a camera. The repeatability in instrument actuations was assessed during 100 mm deep automated insertions with a linear motor. In addition to tip position, tip angles were tracked during the insertions.
The targeting error (mean absolute error ± standard deviation) during manual steering to 5 different targets in stiff tissue was 0.5 mm ± 1.1. This variability in manual tip placement (1.1 mm) was less than the variability among automated insertions (1.4 mm) in the same tissue type. An increased tissue stiffness resulted in an increased lateral tip displacement. The tip angle was directly controlled by the user interface, and remained unaffected by the tissue stiffness.
This study demonstrates the ability to manually steer needles to predefined target locations under image guidance.
研究人类操作员通过主动式、尖端可弯曲的可控针在不完全拔出针的情况下手动纠正针插入路径错误的能力。
该针由外径1.32毫米的套管组成，尖端附近有一个挠性接头，以及一个可伸缩的探针。针的弯曲刚度类似于20号皮下注射针。在手动插入过程中，通过将针导向预定义目标并使其从直线插入线横向位移20毫米来评估针的功能。在摄像头的图像引导下，在5个方向和2种组织模拟物中进行导向任务。使用线性电机在100毫米深度的自动插入过程中评估仪器操作的重复性。除了尖端位置外，在插入过程中还跟踪尖端角度。
在硬组织中手动导向5个不同目标时的靶向误差（平均绝对误差±标准差）为0.5毫米±1.1。手动尖端放置的这种变异性（1.1毫米）小于相同组织类型中自动插入之间的变异性（1.4毫米）。组织硬度增加导致尖端横向位移增加。尖端角度由用户界面直接控制，不受组织硬度影响。
本研究证明了在图像引导下将针手动导向预定义目标位置的能力。
