Development of Tele-echography Interface Considering Contact Force of Ultrasound Probe to Body Surface

Abstract

We have developed a human interface for medical doctor to control a remote diagnosis robot by a controller in tele-echography. We have completed signal and image communication between the robot and controller. The remote doctor was able to sense restitution force on patient's body surface by introducing bilateral control method. However, not only the position of the ultrasound probe but also the positional relationship between the probe and body surface were difficult to understand because all information for the doctor was on the remote monitor. Therefore we have reconstructed all the environment of the patient's body shape and the probe to be visualized as computer graphics (CG) using OpenGL. To evaluate delay time, the both positions of the probe and the actual handle were visualized on the same GUI window. To calculate the distance between the probe and the patient for safe control of the robot, precise shape of body surface was measured by detecting contact force on body and was reconstructed by introducing Delaunay triangulation method. We have also designed the console window including echogram, patient scene and CG with automatic control of image quality by considering contact force. We have confirmd operativity of the interface through actual remote diagnosis of tele-echography.