CLINICAL-EVALUATION OF EXTRACELLULAR AMINO-ACIDS IN SEVERE HEAD TRAUMA BY INTRACEREBRAL IN-VIVO MICRODIALYSIS

The underlying mechanisms of neuronal dysfunction in head injury are m ultifactorial and not fully understood. Recent experimental evidence i ndicates that excitatory amino acids-for example, glutamate-may play a key part in secondary neuronal damage after head injury. A patient wi th severe head trauma was monitored for extracellular amino acids by i ntracerebral in vivo microdialysis. Very high concentrations of glutam ate, glycine, and gamma-aminobutyric acid were recorded in the microdi alysate specimens collected over three hours. In vivo microdialysis in head injury may prove to be a useful tool in understanding the pathog enesis of cell death in head trauma.