E.K. VALEEV, S.V. OGURTSOV, I.E. VALEEV, I.A. SHULMAN Republic Clinical Hospital of the MH of RT, 138 Orenburskiy Trakt, Kazan, Russian Federation, 420064  Valeev E.K. — D. Med. Sc., Chief Researcher, tel. (843) 296-88-52, e-mail: ekv44@mail.ru Ogurtsov S.V. ― neurosurgeon, tel. +7-917-853-95-86, e-mail: sergogurtsov@rambler.ru Valeev I.E. ― Cand. Med. Sc., neurosurgeon, tel. (843) 296-88-52, e-mail: […]