Doctor  of Medical Sciences, Head of the Department of Endoscopy, State Budgetary  Healthcare Institution “City Clinical Hospital No. 31 named after.  Academician G.M. Savelyeva" of the Department of Health, Chief  Researcher of the Research Laboratory of Surgical Gastroenterology and  Endoscopy of the Federal State Budgetary Educational Institution of Higher  Education "Russian National Research Medical University named after.  N.I. Pirogov" Ministry of Health of Russia, Moscow