Intraoperative navigation for liver resection by tablet terminal based on augmented reality

Abstract

Introduction: Most of recent surgical navigation systems employ expensive machines. A simple navigation system for liver resection by marker-based augmented reality (AR) which runs on a tablet terminal has been newly developed. Method: Three-dimensional (3-D) images of hepatic parenchyma, vessels and tumors were constructed by a simulation software (SYNAPSE VINCENT, FUJIFILM, Japan) utilizing preoperative CT data, and those were exported to a tablet terminal (ICONIA W4-820/FP, Acer, Taiwan). In operation, the 3-D images were presented on a display of the tablet terminal by real scale and in appropriate position, by visual recognition of a small plastic AR marker which was sutured on the liver surface. The navigation system was employed in 18 cases of liver resections. Position gap was measured in each operation by comparing the liver edge of gallbladder bed or umbilical fissure with those of 3-D reference images. Results: The 3-D images were successfully displayed in all cases. The system clearly indicated not only the locations of intrahepatic tumor and vessels but also the extent of the liver parenchyma to be resected. The median gap of image position ranged 0.3 to 3.2 cm (1.6 cm in median). Conclusions: This study showed a sufficient accuracy of the navigation system which is simple and easily-obtainable. It is a promising and evolvable tool for image-guided liver surgery.