Safety of transcranial magnetic stimulation in patients with multiple sclerosis
Authors: Malakhov V. O. , Gaponov P. K. 
Published: October 2021

Multiple sclerosis is a demyelinating, degenerative disease that is associated with increasing disability. Multiple sclerosis is one of the main reasons for the permanent disability of young people. To improve the quality of life there is a need for comprehensive rehabilitation measures, especially in the initial stages of the disease. In recent years, there are new techniques of non-invasive neuromodulation that can improve the patient's recovery. Methods that can affect neuroplasticity include transcranial magnetic stimulation. The aim of this study was to assess the safety and potential for adverse effects of transcranial magnetic stimulation during and after a session in patients with multiple sclerosis. The results were obtained by examining 80 patients with multiple sclerosis (diagnosed according to the criteria of McDonald et al., 2017), who received a course of rTMS. All patients received disease-modifying therapy drugs, taking into account the recommendations of the European MS Treatment Guidelines Released. For the purpose of noninvasive neuromodulation in the process of treatment and rehabilitation, rTMS was used. The course of treatment was performed on a MagVenture device, MagPro X100 and an 8-shaped inductor (coil). All patients were tested using a safety questionnaire and selected according to the indications and contraindications of rTMS. Depending on the leading clinical manifestations, different protocols for rTMS were used. Protocols with high-frequency stimulation of DLPFC zones and primary motor cortex, M1 zone were selected. Statistical data processing was performed using the licensed office suite Microsoft Excel 2013. In some patients with multiple sclerosis (35.0 %) during rTMS, during the session or the day after the session, and in some cases later, adverse events were noted. Depending on the stimulation zone, the frequency of their occurrence was different. When using high-frequency rTMS of the primary motor cortex, adverse events were observed in 32.5 % of cases in the form of discomfort in the area of the procedure, headache, changes/decrease in hearing, neck pain, episodic paroxysmal anxiety. When using high-frequency rTMS DLPFK, adverse events were observed in 33.8 % of cases in the form of discomfort in the area of the procedure, headache, hearing loss/transient changes, transient changes in cognitive function, neck pain, high blood pressure, shooting pain in the temporal area on the stimulation side. According to our observations, adverse events were observed not only during rTMS, some of them continued to be observed during the day after the session and more. Thus, TMS occupies an important place in the process of non-drug rehabilitation of patients with multiple sclerosis. The safety of TMS includes careful selection of patients in accordance with the criteria of indications and contraindications of the procedure, the patient's consent to TMS, the choice of stimulation protocol with personalized selection of parameters, prevention of side effects and monitoring of the patient during TMS.