Copyright © 2012 TBDHD.Diagnosis of (persistent) vegetative state (PVS), minimally consciousness state (MCS) or mesencephalic "locked-in" syndrome (LIS) is challenging resting only on clinical grounds in cases awakening from acute comatose states with eye opening but no consistent cooperativeness. These descriptions are of uttermost critical importance in terms of prognosis declaration and treatment level selection. Stimulus-evoked and task-evoked functional magnetic resonance imaging (fMRI) or resting state fMRI can be used for this purpose. Three cases, in whom convincing discrimination of PVS, LIS and MCS was impossible to be clinically attained are herein presented and discussed. For the sake of fMRI technology, diagnoses of LIS connected to pontomesencephalic infarction, PVD due to pontine hemorrhage and MBD from global cerebral ischemia could be insured. Utility of fMRI in the neurocritical care and neurovascular disease practices is briefly presented.