Patel Niravkumar A, van Katwijk Tim, Li Gang, Moreira Pedro, Shang Weijian, Misra Sarthak, Fischer Gregory S
Annu Int Conf IEEE Eng Med Biol Soc. 2015 Aug;2015:4869-74. doi: 10.1109/EMBC.2015.7319484.
Magnetic resonance imaging (MRI) provides excellent image contrast for various types of tissues, making it a suitable choice over other imaging modalities for various image-guided needle interventions. Furthermore, robot-assistance is maturing for surgical procedures such as percutaneous prostate and brain interventions. Although MRI-guided, robot-assisted needle interventions are approaching clinical usage, they are still typically open-loop in nature due to the lack of continuous intraoperative needle tracking. Closed-loop needle-based procedures can improve the accuracy of needle tip placement by correcting the needle trajectory during insertion. This paper proposes a system for robot-assisted, flexible asymmetric-tipped needle interventions under continuous intraoperative MRI guidance. A flexible needle's insertion depth and rotation angle are manipulated by an MRI-compatible robot in the bore of the MRI scanner during continuous multi-planar image acquisition to reach a desired target location. Experiments are performed on gelatin phantoms to assess the accuracy of needle placement into the target location. The system was able to successfully utilize live MR imaging to guide the path of the needle, and results show an average total targeting error of 2.5±0.47mm, with an average in-plane error of 2.09±0.33mm.
磁共振成像（MRI）能为各种类型的组织提供出色的图像对比度，使其在各种图像引导下的穿刺干预方面比其他成像方式更具优势。此外，机器人辅助技术在经皮前列腺和脑部干预等外科手术中日益成熟。尽管MRI引导下的机器人辅助穿刺干预已接近临床应用，但由于缺乏术中连续的针跟踪，它们本质上仍通常是开环的。基于闭环针的手术可以通过在插入过程中校正针的轨迹来提高针尖放置的准确性。本文提出了一种在术中MRI连续引导下进行机器人辅助的、灵活的不对称针尖穿刺干预系统。在连续多平面图像采集过程中，由MRI兼容机器人在MRI扫描仪的孔腔内操纵柔性针的插入深度和旋转角度，以到达期望的目标位置。在明胶模型上进行实验，以评估针放置到目标位置的准确性。该系统能够成功利用实时MR成像来引导针的路径，结果显示平均总靶向误差为2.5±0.47mm，平均平面内误差为2.09±0.33mm。
