BIOELECTRIC ACTIVITY OF THE BRAIN AND BRAIN BLOOD VESSELS FUNCTIONING IN ADOLESCENTS IN A LONG-TERM REMISSION (5-12 YEARS) RECOVERED FROM LYMPHOID TUMORS
Background: The five-year survival rate in children recovered from lymphoid tumors is up to 80%. However, long-term consequences may occur. Evaluation of the CNS functional state has not been studied sufficiently in a long-term follow-up of cured patients. Objective: Evaluation of the functional state of the brain in patients in remission recovered after treatment for lymphomas. Methods: The study enrolled 16 adolescents (8 boys and 8 girls) aged 11 to 20 years (mean age 14 years) in remission for 5-12 years recovered from lymphoid tumors (ALL and NHL). The subjects were diagnosed at the age of 2 to 14 years. All patients received antitumor treatment according to the mBFM-90 protocol. The results of electroencephalogram (EEG), echoencephalogram, and rheoencephalogram examinations were studied. The EEG comparison group included healthy children. Results: At the time of the conducted study, in most cases (70%) complaints involved headaches, sleep disturbance, and dizziness. After examination signs of retardation of venous outflow in the basins of internal carotid and vertebral arteries were revealed, as well as signs of liquorodynamic disturbances. Comparative EEG mapping (spectral characteristics of EEG in adolescents in remission were compared with the normative database of EEG records) demonstrated general decrease in amplitude of bioelectrical activity in adolescents in remission. The spectral power values (SM) were reliably reduced in beta-1 and beta-2 frequency bands (p<0.05). Conclusion: The greatest changes were observed in those adolescents in remission who was younger than 6 years at the beginning of the treatment and underwent prophylactic cranial irradiation. In addition to a general decrease in the amplitude of the oscillations, they had an increase in the theta-activity index in the frontal areas of the cerebral cortex. The data of neurobiological research can be used to develop individual rehabilitation programs for children with oncohematological diseases.