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：磁共振引导下的微波消融（MWA）已被证明对治疗小尺寸肝细胞癌（HCC）有效，但现有技术因进针速度和精度不足导致工作流程欠佳。本文提出一种紧凑型体装式磁共振兼容机器人，可在封闭式磁共振扫描仪中实现精准进针引导。该机器人平台由两个堆叠的笛卡尔XY轴平移台组成，每个平台具备两个自由度，协同完成进针引导。机器人采用3D打印气动涡轮驱动，配合磁共振兼容斜面齿轮传动系统。气动阀门与控制机电组件置于磁共振控制室，通过气动传输管路与光纤与机器人连接。自由空间实验表明，在80mm穿刺深度下，机器人辅助进针误差为2.6±1.3mm。通过磁共振引导仿真体实验验证了机器人的磁共振兼容性与靶向性能。未来工作将聚焦系统优化及动物实验验证。