The value of spontaneous EEG oscillations in distinguishing patients in vegetative and minimally conscious states.

OBJECTIVE The value of spontaneous electroencephalography (EEG) oscillations in distinguishing patients in vegetative state (VS) and minimally conscious states (MCS) was studied. METHODS We quantified dynamic repertoire of EEG oscillations in resting condition with closed eyes in patients in VS and MCS. The exact composition of EEG oscillations was assessed by the probability-classification analysis of short-term EEG spectral patterns. RESULTS The probability of delta, theta, and slow-alpha oscillations occurrence was smaller for patients in MCS than for VS. Additionally, only patients in MCS demonstrated fast-alpha oscillation occurrence. Depending on the type and composition of EEG oscillations, the probability of their occurrence was either etiology dependent or independent. The probability of EEG oscillations occurrence differentiated brain injuries with different etiologies. CONCLUSIONS Spontaneous EEG oscillations have a potential value in distinguishing patients in VS and MCS. SIGNIFICANCE This work may have implications for clinical care, rehabilitative programs, and medical-legal decisions in patients with impaired consciousness states following coma due to acute brain injuries. HIGHLIGHTS The probability of delta, theta, and slow-alpha oscillations occurrence was smaller and the probability of fast-alpha oscillations occurrence was higher for patients in MCS than for patients in VS. The probability of EEG oscillations occurrence differentiated brain injuries with different etiologies. Spontaneous EEG has a potential value in distinguishing patients in VS and MCS.