Electroencephalography quantitative indicators of patients with bilateral vocal fold paralysis

Abstract

Treatment of patients with bilateral vocal fold paralyses remains a complicated task. Study of central mechanisms of realization of larynx functions in case of stenosis is of interest. By electro­encephalography method (EEG) patients with bilateral vocal fold paralysis were examined: 55 patients without surgical treatment (group I), and 51 patients who had unilateral chordoarytenoidotomy (group II). All the patients showed  changes in percentage content of the α - and β-rhythms and Δ- and θ-rhythms ("slow" waves). The group II patients demonstrated more pronounced rhythms, as compared with the control group. During the background recording, in group I the increase in the percentage content of the Δ-rhythms in frontal and parietal directions up to 28.2±2.3 and 29.2±2.4%, was seen, the group II patients showed the increase in Δ-activity up to 32.2±2.8 and 35.4±2.9% in frontal, temporal and parietal directions accordingly. Besides, the group II patients proved to have an increasing of β-rhythms activity in all the directions, as compared to the control group, as well as an increasing of θ-rhythms in temporal and parietal directions. Herewith, the increase of θ-rhythms in temporal directions up to 21.4±2.2%, was much higher as compared to group I data 16.5±1.3%. Besides, all the patients showed decrease in α-rhythms amplitude. So, the redistribution of electroencephalography rhythms in the way of α-range fluctuation decrease and increase of slow wave activity (θ- и Δ- waves), as well as α-rhythms amplitude decrease in patients having vocal fold motor disorders testify to the prevailing influence of subcortical structures on the bioelectrical brain activity and facts of nervous processes depletion in brain, including chronic hypoxia of patients suffering from larynx stenosis of paralytic origin.