FAILURE OF LOCALIZED HEAD COOLING TO REDUCE BRAIN TEMPERATURE IN ADULT HUMANS

NON-INVASIVE brain temperature measurements using proton magnetic reso nance spectroscopy were used to test the hypothesis that localized hea d cooling would reduce brain temperature in 10 normal adult humans. Te mperature reductions of the head surface to 15.8 +/- 3.5 degrees C did not reduce brain temperature measured in the superficial cortex (36.8 +/- 0.5 degrees C) or thalamus (36.6 +/- 0.7 degrees C), as compared to measurements obtained with a head surface temperature of 34.7 +/- 1 .6 degrees C (37.0 +/- 0.6 degrees C and 36.6 +/- 0.4 degrees C, respe ctively). There was no change in the temperature gradient from the sup erficial to deep brain locations in the presence or absence of head co oling, and brain temperature did not decrease as a function of the dur ation of head cooling for periods up to 50 min. There was no correlati on between the scalp surface (range: 10-38 degrees C) and brain temper ature at either the deep or superficial locations. (C) 1998 Lippincott Williams & Wilkins.