Limited physical access to target organs of patients inside an MRI scanner is a major obstruction to real-time MRI-guided interventions. Traditional teleoperation technologies are incompatible with the MRI environment and although several solutions have been explored, a versatile system that provides high-fidelity haptic feedback and access deep inside the bore remains a challenge. We present a passive and nearly frictionless MRI-compatible hydraulic teleoperator designed for in-bore liver biopsies. We describe the design components, characterize the system transparency, and evaluate the performance with a user study in a laboratory and a clinical setting. The results demonstrate $< 5$% difference between input and output forces during realistic manipulation. A user study with participants conducting mock needle biopsy tasks indicates that a remote operator performs equally well when using the device as when holding a biopsy needle directly in hand. Additionally, MRI compatibility tests show no reduction in signal-to-noise ratio in the presence of the device.

中文翻译：

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使用力反馈实现钻孔内 MRI 引导活检

MRI 扫描仪内对患者靶器官的物理接触有限是实时 MRI 引导干预的主要障碍。传统的远程操作技术与 MRI 环境不兼容，尽管已经探索了多种解决方案，但提供高保真触觉反馈和进入钻孔深处的多功能系统仍然是一个挑战。我们提出了一种被动且几乎无摩擦的 MRI 兼容液压遥控操作器，专为钻孔肝活检而设计。我们描述了设计组件，表征了系统透明度，并通过实验室和临床环境中的用户研究来评估性能。结果表明，在实际操作过程中，输入力和输出力之间存在 $<5$% 的差异。一项对执行模拟针活检任务的参与者进行的用户研究表明，远程操作员在使用该设备时的表现与直接手持活检针时的表现一样好。此外，MRI 兼容性测试表明，在设备存在的情况下，信噪比不会降低。