Stiffness perception in laparoscopic surgery has an important role in achieving appropriate tissue manipulation. The need for haptic feedback to perceive tissue stiffness and the reduce in haptic feedback when using laparoscopic instruments suggest an inability to sufficiently ex
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Stiffness perception in laparoscopic surgery has an important role in achieving appropriate tissue manipulation. The need for haptic feedback to perceive tissue stiffness and the reduce in haptic feedback when using laparoscopic instruments suggest an inability to sufficiently experience stiffness perception during laparoscopic surgeries. Better understanding of the perception of tissue stiffness could contribute to the development of better laparoscopic instruments. A stiffness ranking task has been performed with 16 participants, to study the influence of force transmission ratio, contact area and grasping strategy on the haptic perception of variable tissue stiffness. Using a newly developed set of laparoscopic grasper handles varying in the chosen independent variables, being the force transmission ratio and contact area, the participants performed multiple grasps with each grasper handle on a randomized order of tissue samples with three different stiffness levels and ranked them according to the perceived level of stiffness. Force measurements were done during the task and a survey was conducted afterwards. The results indicate that force transmission ratio and contact area do not influence the haptic perception of variable tissue stiffness. In terms of grasping strategy, a lower force exertion is shown to be desirable for perceiving the variable tissue stiffness, while the amount of grasps per tissue sample have not shown to influence the perception. Future studies with larger sample sizes might indicate a difference between high and low force transmission ratios. It is concluded that future designs of laparoscopic grasper handles might not be restricted in terms of force transmission ratio and contact area requirements when a greater haptic perception is aimed at. More haptic perception of variable tissue stiffness is gained in the surgical domain of applying the appropriate grasping strategies.