Safety and Feasibility of St. Mark's Electrode for the Hypoglossal Nerve and Cortico-lingual Pathway Study

"NCS of nervus hypoglossus (evaluation of M-response parameters) was carried out using a 4-channel electromyographic machine. The stimulation will be carried out from three points:~1. angle of the lower jaw (proximal point),~2. the area of the carotid triangle (distal point),~3. directly from the electrode of St. Mark when it is localized on the muscles of the tongue.~The initial stimulation parameters: strength of an electric current 20 mA, stimulus duration 0.2 ms, and frequency 1 Hz. To achieve supramaximal stimulation, the stimulation strength will be increased with a step of 1-2 mA to a maximum of 35 mA, the duration of the stimulus will be increased to 0.3 ms."

"TMS will be carried out using a Magstim 200 magnetic stimulator connected with a BiStim module (Magstim Co. Ltd., Whitland, Wales, UK). The generated magnetic pulses will be delivered by the coil 65 mm in diameter tangentially located relative to the scalp in the F7 projection - T3 and F8-T4 (according to the international scheme 10-20). The area of cortical stimulation will be localized by supplying single pulses with gradual increase, with a coil displacement with a step of 1 cm, until the contraction of the facial muscles will be obtained, followed by the determination of the MEP threshold value. Analysis of conduction by cortical-lingual pathway will be performed at TMS with magnetic stimulus intensity 20-30% above the MEP threshold."