Although clinical examination is the gold standard for differential diagnosis between unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS), clinical signs denoting the first occurrence of conscious behavior in patients with UWS have not been clarified. In this prospective single-center cohort study, 31 consecutive patients with UWS after traumatic brain injury (TBI) (17 patients) or non-TBI were assessed with the Coma Recovery Scale Revised (CRS-R) at admission to a rehabilitation department and after 1, 2, 3, 6, and 12 months. Of the 21 patients who recovered consciousness during the study, 90.5% recovered consciousness within the first 3 months. At the first diagnosis of emergence from UWS, 52.4% of patients showed signs of awareness in only one CRS-R subscale. In particular, 42.9% of patients showed conscious behaviors on the visual CRS-R subscale (23.8% showed visual fixation and 19.1% showed visual pursuit), and 9.5% showed conscious behaviors on the motor CRS-R subscale (half showed localization to a noxious stimulus and half showed object manipulation). Moreover, 23.8% of patients had conscious behaviors on two CRS subscales, always involving the visual and motor CRS-R subscales. The remaining patients showed conscious behaviors on more than two CRS-R subscales. In conclusion, visual fixation and visual pursuit are the commonest early clinical signs denoting MCS. When emerging from UWS, patients with TBI often showed more signs of consciousness and had higher CRS-R scores than patients with non-TBI.
Keywords: Coma Recovery Scale Revised; MCS; TBI; disorders of consciousness; vegetative state.