Electromagnetic noise measurement of the Motor Assisted Robotic Stereotaxy System (MARS)

Stereotactic intervention is a standard way to treat neuropsychiatric degenerative diseases. Deep brain stimulation (DBS) presents an effective tool to treat Parkinson’s disease (PD) and other movement disorders as well as psychiatric diseases [1]. Besides PD, DBS can be used to treat chronic pain or mental decline [2]. Accurate positioning of stimulating probes in the patient’s brain is crucial to the outcome of the interventions [3]. The use of high-accuracy robotic aids is beneficial and many systems have been introduced since the late 1980’s. An overview can be found in [4]. During the surgical intervention, an electrode is inserted into the brain. The neuronal firing at the electrode’s tip is continuously monitored using a microelectrode recording (MER) system. The signal is displayed to the surgeon via loudspeakers. Every brain region has its specific firing patterns, expressed through frequency and amplitude [5]. Skilled surgeons can determine the current position of the electrode based on the firing pattern they hear. Once the target position is reached, the area is stimulated by the electrode. One problem that arises when using robotic aids is the electromagnetic noise induced by the motors and controllers of the robot. This noise can interfere undesirably with microelectrode recordings and stimulations. The Motor Assisted Robotic Stereotaxy system (MARS) is a newly developed robot for stereotactic interventions [6]. It was specially designed to show low electromagnetic noise. This is achieved by using lownoise brushless DC motors and controllers, consequent shielding of current-carrying cables and careful mechanical and electric design. In this work, we present the results of electronic noise measurements and we discuss the impact of the noise on the MER system.