Purpose To test the sensitivity and reproducibility of a 25-gauge force-sensing micropick during microsurgical maneuvers that are below tactile sensation. Methods Forces were measured during membrane peeling in a “raw egg” and the chick chorioallantoic membrane models (N = 12) of epiretinal membranes. Forces were also measured during posterior hyaloid detachment and creation of retinal tears during vitrectomy in live rabbits (n = 6). Results With the raw egg model, 0.5 ± 0.4 mN of force was detected during membrane peeling. In the chorioallantoic membrane model, delaminating the upper membrane produced 2.8 ± 0.2 mN of force. While intentionally rupturing the lower membrane to simulate a retinal tear, 7.3 ± 0.5 mN (range, 5.1–9.2 mN; P < 0.001) of force was generated while peeling the upper membrane. During vitrectomy, the minimum force that detached the posterior hyaloid was 6.7 ± 1.1 mN, which was similar to the force of 6.4 ± 1.4 mN that caused a retinal tear. The rate of force generation, as indicated by the first derivative of force generation, was 3.4 ± 1.2 mN/second during posterior hyaloid detachment, compared with 7.7 ± 2.4 mN/second during the creation of a retinal tear (P = 0.04). Conclusion Force-sensing microsurgical instruments can detect forces below tactile sensation, and importantly, they can distinguish the forces generated during normal maneuvers from those that cause a surgical complication.

This paper reports new developments and optimizations for clinical use of the Steady-Hand Eye Robot for vitreoretinal surgery. Vitreoretinal surgery requires precise micro-manipulation of delicate tissues. Surgical performance is limited by physiological hand tremor, fatigue, poor kinesthetic feedback, as well as patient movement. The previously developed Steady-Hand Eye Robot has been extensively used in in vivo experiments. Several safety and ergonomic limitations observed in the in vivo environment serve as motivation for a novel robot wrist design. The new robot wrist consists of a symmetric remote center of motion (RCM) tilt mechanism and a slim tool holder with a quick release mechanism for the surgical instruments. The RCM tilt mechanism provides a tilt motion range of ±45° and a stiffness of 21 N/mm. Two different release force thresholds for the quick release mechanism were designed. The soft configuration requires 2–3 N to retract the surgical instruments while the hard configuration requires 5–6 N.

NA. Laryngoscope, 127:2495-2500, 2017.

Objectives/Hypothesis: To evaluate gains in microlaryngeal precision achieved by using a novel robotic "steady hand" microsurgery platform in performing simulated phonosurgical tasks.Study Design: Crossover comparative study of surgical performance and descriptive analysis of surgeon feedback. Methods: A novel robotic ear, nose, and throat microsurgery system (REMS) was tested in simulated phonosurgery. Participants navigated a 0.4-mm-wide microlaryngeal needle through spirals of varying widths, both with and without robotic assistance. Fail time (time the needle contacted spiral edges) was measured, and statistical comparison was performed. Participants were surveyed to provide subjective feedback on the REMS.Results: Nine participants performed the task at three spiral widths, yielding 27 paired testing conditions. In 24 of 27 conditions, robot-assisted performance was better than unassisted; five trials were errorless, all achieved with the robot. Paired analysis of all conditions revealed fail time of 0.769 6 0.568 seconds manually, improving to 0.284 6 0.584 seconds with the robot (P 5 .003). Analysis of individual spiral sizes showed statistically better performance with the REMS at spiral widths of 2 mm (0.156 6 0.226 seconds vs. 0.549 6 0.545 seconds, P 5 .019) and 1.5 mm (0.075 6 0.099 seconds vs. 0.890 6 0.518 seconds, P 5 .002). At 1.2 mm, all nine participants together showed similar performance with and without robotic assistance (0.621 6 0.923 seconds vs. 0.868 6 0.634 seconds, P 5 .52), though subgroup analysis of five surgeons most familiar with microlaryngoscopy showed statistically better performance with the robot (0.204 6 0.164 seconds vs. 0.664 6 0.354 seconds, P 5 .036).Conclusions: The REMS is a novel platform with potential applications in microlaryngeal phonosurgery. Further feasibility studies and preclinical testing should be pursued as a bridge to eventual clinical use.