MR-guided microwave ablation (MWA) has proven effective in treating hepatocellular carcinoma (HCC) with small-sized tumors, but the state-of-the-art technique suffers from sub-optimal workflow due to speed and accuracy of needle placement. This paper presents a compact body-mounted MR-conditional robot that can operate in closed-bore MR scanners for accurate needle guidance. The robotic platform consists of two stacked Cartesian XY stages, each with two degrees of freedom, that facilitate needle guidance. The robot is actuated using 3D-printed pneumatic turbines with MR-conditional bevel gear transmission systems. Pneumatic valves and control mechatronics are located inside the MRI control room and are connected to the robot with pneumatic transmission lines and optical fibers. Free space experiments indicated robot-assisted needle insertion error of 2.6$\pm$1.3 mm at an insertion depth of 80 mm. The MR-guided phantom studies were conducted to verify the MR-conditionality and targeting performance of the robot. Future work will focus on the system optimization and validations in animal trials.

翻译：磁共振引导的微波消融（MWA）已被证明对治疗伴有小尺寸肿瘤的肝细胞癌（HCC）有效，但现有技术因针穿刺的速度和精度不足而存在工作流程欠佳的问题。本文提出一种紧凑的体装式MR兼容机器人，可在封闭式磁共振扫描仪中运行以实现精确的针引导。该机器人平台由两个堆叠的笛卡尔XY级组成，每个级具有两个自由度，可辅助针引导。机器人采用3D打印气动涡轮机驱动，并配备MR兼容斜面齿轮传动系统。气动阀和控制机电设备位于MRI控制室内，通过气动传输线和光纤与机器人连接。自由空间实验表明，在80 mm穿刺深度下，机器人辅助的针穿刺误差为2.6±1.3 mm。通过MR引导的仿体实验验证了机器人的MR兼容性和靶向性能。未来工作将聚焦于系统优化及动物试验验证。