Received: 12 July 2018
Accepted: 1 November 2018
First Online: 21 December 2018
Ethics approval and consent to participate
: Approval of the local Ethics committee of Federal State Autonomous Institution “N.N. Burdenko National Medical Research Center of Neurosurgery” of the Ministry of Health of the Russian Federation was received.
: Сonsent for publication was obtained from each patient.
: The authors declare that they have no competing interests.