Empirical Evaluation of a 3D Virtual Simulator of Hysteroscopy Using Leap Motion for Gestural Interfacing

Surgical training using 3D virtual reality simulators has become an important routine in medical education. Recent research points to Leap Motion as an exciting interface for the control of virtual surgical instruments due to its simplicity and low-cost characteristics. However, previous studies using Leap Motion only evaluated movements of the whole hand, without considering individual finger movements during the manipulation of surgical instruments. This work investigates the use of Leap Motion as an interface for the capture of basic hand and finger movements during a simulated hysteroscopy using a 3D-printed hysteroscope model. We created a virtual simulated uterine environment containing a hysteroscope controlled by movements of the hand and fingers of a user actuating on a 3D-printed model hysteroscope. The model hysteroscope was positioned in a pivot basis allowing the capture of the following basic movements: leftward/rightward, upward/downward, forward/backward, and extrusion/retraction of the virtual resection loop (which rests on the end of the virtual virtual resectoscope). The findings indicate that the arc-shaped paths of the hysteroscope's alpha plane (rightward/leftward) and beta plane (upward/downward) movements are satisfactorily simulated by the virtual reality system. Using Intraclass Correlation, was noted that the similarity between the calculated (ideal standard) and measured arcs was highly significant on both planes (r = 0.9599 on the alpha plane, and r = 0.9208 on the beta plane). Also, the forward/backward trajectory is a straight line; the pinch gesture decreases its accuracy when increase its distance from the Interaction Box of Leap Motion. The results were satisfactorily since compared with previous works, which used Leap Motion for the capture of hands-free gesturing.