Evaluation of diagnostician user interface aspects in a virtual reality-based tele-ultrasonography simulation

Ultrasonography (USG) is a common medical examination that can be performed remotely and that highly benefits from robotics. In this paper, we evaluate a novel interface for a telediagnosis system that features haptic feedback and a 2D/3D visualization of the remote site. A Virtual Environment (VE) representing the patient site was used for the validation to stress the interaction capabilities of the interface and to decouple expert's interface performance from the effects of the whole teleoperation loop of a telediagnosis system. The interface evaluation measures include the accuracy that doctors achieve when positioning the interface's end-effector in the VE and the success of experts to perform tasks related to cardiac USG that require force feedback. Twelve experienced sonographers performed four experiments in which visualization modality and VE navigation technique varied. Given the limitations of an evaluation in simulated settings, both quantitative results and experts' opinions suggest that the interface is suitable for integration in tele-USG systems. After a positive evaluation of latencies and rendered forces, we show how navigation condition influences the accuracy of the end-effector positioning as well as the covered distance and the elapsed time to accomplish the tasks. Similarly, we highlight the effect of visualization on accuracy.