Robotically assisted needle driver: Evaluation of safety release, force profiles, and needle spin in a swine abdominal model

Objective: The objective of this study was to evaluate two features of a new rotating needle driver in a domestic swine model: (1) a quick release safety mechanism and (2) the impact of spinning the needle on the force profile. Materials and methods: The experiments were conducted in a multi-modality interventional suite. An initial CT scan was obtained to determine the location of the target, in the liver or lung. The robotic arm was positioned directly over the marked skin entry point. Control parameters were set to rotation speeds of 0, 90, or 180 rpm. The breakaway force magnitude was also preset to a predetermined force. The physician used the joystick to drive the needle towards the target while the system recorded needle insertion depth and forces. Results: Sixteen insertions were completed (14 in liver and 2 in lung) and 12 released the needle upon the desired set force. The mean response time of the quick release mechanism was 202 ± 39 ms. Needle rotation resulted in reduced insertion force. Conclusion: The robot-assisted needle insertion system was shown to be functional in a multimodality imaging clinical environment on a swine model. The system has potential future applications in precision minimally invasive procedures including biopsy and radiofrequency ablation.