SEP allow an early reliable assessment of both poor and good prognosis in SBD, in particular when applied serially. BLCR does not always imply a fatal diagnosis, as a circumscribed contusional lesion rarely may lead to selective reversible blockage of ascending somatosensory pathways in the brainstem. In contradiction to this lesional etiology, a hypoxia-induced BLCR pattern seems to correlate strictly with a poor prognosis, reflecting a different pathogenesis with diffuse destruction of cortex and thalamocortical pathways.