Comparative Study of Potential-Based and Sensor-Based Surgical Navigation in Several Liver Environments

Medical navigators have gained recent attention for application in surgery to provide the surgeon with the position and orientation of malignant tumors as accurately as possible. Currently, extensive research is being conducted on producing surgical navigators; however, their practical application is difficult in the case of organ deformation. This study presents a medical navigation system using two types of algorithms to select a pathway from the scalpel tip near a malignant tumor in a 3D liver environment, which avoids blood vessels (arteries, veins, and portal veins) and the malignant tumor when they are regionally segmented inside the liver. The first algorithm involves potential-based navigation, in which the scalpel tip reaches its destination by adjusting the attraction to the destination (currently the malignant tumor) and the repulsion from the blood vessels. The second algorithm involves sensor-based navigation where the surgeon moves the scalpel in a straight line in the direction of the malignant tumor. When a blood vessel is encountered, the scalpel is moved in a clockwise or counterclockwise direction in a certain plane over a certain distance to avoid the blood vessel. It is then moved in a straight line in the direction of the malignant tumor again after approaching the malignant tumor monotonically or asymptotically.

In this study, both navigation algorithms select a path near the malignant tumor in the 3D liver environments with diverse shapes and arrangements of blood vessels and malignant tumors. The potential-based navigation algorithm then selects a shorter straight path near the malignancy, but the direction of the incision varies in a complex manner. Lastly, the sensor-based navigation algorithm selects a longer circuitous path near the malignancy, but the incision direction is uniform.