Toward Bipolar Electrosurgery with Concentric Tube Robots

Abstract

Some of the earliest clinical motivations for concen- tric tube robots (CTRs) involved procedures which are often accomplished via electrosurgery [1], [2]. However, the development of electrosurgery in physical prototypes was initially left to future work, as early research focused on mechanics-based models and model-based control methods [3], [4]. In recent years, monopolar electro- surgery has been delivered through CTRs in physical prototypes [5], [6]. Since the ground is attached else- where on the patient’s body, monopolar tools typically simply require an exposed metal tip to cut. Bipolar tools, in contrast, carry two electrodes, are traditionally made in the shape of a forceps with each jaw containing one of the electrodes. Bipolar electro- surgery has several general advantages over monopolar, in applications where it can be used, including more localized heating and lower voltages, which lead to a lower risk of injury to the patient [7]. Motivated by these advantages, a bipolar electrosurgery forceps has been designed for delivery through for CTRs [8]. In this paper we propose an alternate approach in which the CTR itself acts as one of the active electrodes, with the other delivered through the CTR’s central lumen. We demonstrate teleoperated tissue cutting using a concentric tube robot equipped with this approach to electrosurgery.