Neurofunctional imaging in differential diagnosis and evaluation of outcome in vegetative and minimally conscious state.

Following severe brain injury, some patients will recover wakefulness without signs of consciousness, only showing reflex movements (the vegetative state), while others may show non-reflex movements but remain without functional communication (the minimally conscious state). Functional neuroimaging is providing new insights into cerebral activity in patients with severe brain damage. The mapping of cognitive processes (mostly by measuring regional changes in blood flow, initially by PET and now also by fMRI) is shedding new light on the functional neuroanatomy of consciousness. This review focuses on neurofunctional imaging approaches recently introduced in the differential diagnosis and outcome assessment of patients with chronic disorders of consciousness.