Effectiveness of transcranial electrical stimulation in the treatment of olfactory dysfunction

Up to 25% of the world’s population has various olfactory dysfunctions. Olfactory dysfunction occurs for various reasons and is caused by conductive or neurosensory mechanisms. Post-infectious olfactory dysfunction is most often of neurosensory nature, and restoration of the sense of smell is complicated by the difficulty of influencing all parts of the olfactory nerve. Transcranial electrical stimulation (TES) device has been applied in various neurological diseases, but has not previously been used to treat olfactory pathology. Objective. To study the effectiveness of TES in the area of the olfactory nerve in patients with olfactory dysfunction. Patients and methods. Treatment of 41 patients with post-infectious hyposmia aged 18—71 years (30 women, 73.17%; 11 men, 26.83%) was performed. The Russian version of the Sniffin’ Sticks test (RVSS) was used to assess olfactory thresholds. TES was carried out with an average current of 2.5 mA, a session duration of 30 minutes and a treatment course of 10 days. Results. Olfactory index of patients with olfactory impairment after TES therapy of the olfactory nerve has improved by 1.5 times. TES has resulted in improvement of odor thresholds in 73% of cases. Significant improvement of olfaction and increase of RVSS indices by 50% or more have been determined in 25% of patients. Improvement of odor perception did not depend on the age and sex of patients. Conclusion. TES therapy is an effective method of treating olfactory dysfunction and can be used in comprehensive therapy of olfactory disorders.