E.M. POKROVSKAYA1, 2, V.N. KRASNOZHEN1, 2, S.A. POLISCHUCK2, D.E. TSYPLAKOV3  1Kazan State Medical Academy — Branch Campus of the FSBEI FPE RMACPE MOH Russia, Kazan 2Kazan (Volga) Federal University, Kazan 3Kazan State Medical University, Kazan   Contact details: Pokrovskaya E.M. — MD, otolaryngologist, Professor of the Department of Surgery, Obstetrics and Gynecology Address: 36 Butlerov St., Kazan, Russian Federation, 420012, tel.: +7-917-263-90-96, […]