Abstract
Purpose :
This study investigates the impact of robotic assistance on manipulation skills in retinal surgery. A quantitative evaluation of bimanual behavior for users with various skill levels is presented by comparing freehand and robot-assisted manipulation.
Methods :
Bimanual retinal surgery simulations with five basic maneuvers (Fig. 1), including rotating the globe around three orthogonal axes, a tool pivot motion, and vessel tracing with a tool tip, were conducted on an eye phantom. The user’s dominant hand manipulated a cooperative control eye robot, and the non-dominant hand remained freehand. Two custom-made surgical tools consisting of stainless-steel wires with FBG sensors embedded in the shaft were used to measure forces applied to the contact point between the tool shaft and sclera. Two participants including one engineer and one clinician repeated the five maneuvers twenty times each. For comparison, all manipulations were replicated without robotic assistance. A t-test and one-way analysis of variance with a predetermined value of p < 0.05 were used in statistical analysis.
Results :
The average forces under robot-assisted conditions (80.61 ± 50.32) were notably higher than freehand conditions (56.82 ± 38.97, p = 0.01) in both the dominant and non-dominant hand. The average force recorded from dominant hand maneuvers (78.96 ± 50.09) was significantly higher than that from the non-dominant hand (57.73 ± 39.20, p = 0.004). Higher forces were measured in both hands for the inexperienced participant (76.20 ± 51.32) as compared to the experienced clinician (61.24 ± 37.97), in all experiments. In the case of novice user the force ratio of non-dominant to dominant hand forces during maneuvers, decreased from freehand (0.88 ± 0.27) to robot-assisted (0.77 ± 0.31). In contrast, the ratio increased from freehand (0.5 ± 0.25) to robot-assisted (0.82 ± 0.21) for clinician users.
Conclusions :
Robotic arm stiffness attenuates hand dexterity and tactile feedback. This results in higher tool-to-sclera forces not only in the dominant hand but also the non-dominant hand, during maneuvers. The force ratio represents hand effectiveness during bimanual manipulation. In our study, the clinician utilizes the non-dominant hand to a greater extent than a robot-familiar engineer. Therefore, clinicians may benefit from robot training prior to utilizing robotic assistance in practice.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.