Intraoperative computed tomography-guided robotic needle biopsy system with real-time imaging ability and remote-center-of-motion control

Objective Traditional computed tomography (CT)-guided tumor ablation procedures are often hampered by the need for repeated scans and significant radiation exposure, primarily due to challenges in manual needle insertion and the iterative realignment process. This research introduces an advanced intraoperative CT (iCT)-guided robotic system. The core aim is to enhance procedural accuracy and efficiency by implementing precise, real-time remote-center-of-motion (RCM) control for needle interventions. Methods This study develops an integrated iCT-guided robotic needle biopsy/ablation system. A key distinction from conventional iterative navigation systems is their capability for surgeons to dynamically adjust the intervention line in situ. Real-time visualization of relative positioning is achieved using 3D (three-dimensional) Slicer software. This is coupled with a novel and robust RCM control strategy, meticulously engineered based on screw axis theory and velocity twist, and further optimized with interpolation and feedforward control laws. This framework enables precise, surgeon-guided adjustments of the guiding catheter's posture throughout the procedure. Results The RCM control system effectively and reliably governed the motion of the robotic guidance arm. This ensured that the catheter tube consistently maintained its accurate orientation relative to the target even after multiple surgeon-adjusted posture modifications. Experimental validation demonstrated the system's high performance, achieving exceptionally low RCM errors as 2×10 −4 m. Consequently, any deliberate pause during the robotic arm's movement could be utilized to define a precisely targeted and safe puncture path. Conclusion and significance Comprehensive numerical modeling and experimental evaluations using a TM5-700 robotic arm with phantoms have provided validation for the proposed screw axis-based RCM control concept. Integrating iCT guidance with this RCM system indicates increased precision, operational flexibility, and overall safety of robotic needle-based interventions. This work presents a noteworthy contribution with potential for clinical adoption in various minimally invasive procedures.