“…CSF bathes the neural tissues of the brain and spinal cord and should allow detection of the biochemical products of acute CNS ischemia more rapidly than in serum, particularly if the blood brain barrier is intact. Specific biochemical markers that have been examined to date include lactate, pCO 2 , neuron-specific enolase (NSE) (Nagy et al 2002), excitatory neurotransmitters such as glutamate, aspartate, glycine (Brock et al 1997), tau, glucose, pH, and S100β. These markers also markedly increase in serum at other times, including during surgical procedures unrelated to acute brain injury (Anderson et al 2001;Routsi et al 2006).…”