Authors:

Laureys, S., OWEN, A.M. & Schiff, N.

Reference:

Year of publication:

2004

CBU number:

5845

Abstract:

We review the nosological criteria and function neuroanatomical basis for brain death, coma, vegetative state, minimally conscious state and the locked-in state. Functional neuroimaging is providing new insights into cerebral activity in patients with severe brain injuries. Measurements of cerebral metabolism and brain activations in response to sensory stimuli using positron emission tomography (PET), functional magnetic resonance imaging (fMRI) and electrophysiological methods have significant potential to provide unique windows onto mechanism and possible residual brain function. However, use of these techniques in severely brain-injured persons is methodologically complex and requires careful quantitative analysis and interpretation. In addition, ethical frameworks to guide research in these patient populations must be further developed. At present, nosological distinctions confirmed by clinical examinations remain the standard for accurate diagnosis and prognosis. Neuroimaging techniques, while extremely promising, remain important tools for clinical research that ultimately will extend our understanding of the underlying mechanisms of these disorders.