4.0 T water proton T-1 relaxation times in normal human brain and during acute ethanol intoxication

Background: It has been reported that acute ethanol intoxication decreases the brain water proton magnetic resonance T-1 values, an effect that has be en interpreted to indicate brain dehydration during this condition. Because water macromolecular interactions largely determine tissue water T-1, anot her possible explanation for reduced brain water proton T-1 values is that the interaction between water and brain macromolecules is altered by ethano l. Methods: A 4.0 T magnetic resonance imaging (MRI) instrument was used to me asure brain water proton T-1 relavation times before, during, and after eth anol intoxication (dose, 0.75 mg/kg) in healthy centrols. Results: The T-1 relaxation times as assessed with MRI were highly reproduc ible. The mean, paired ethanol-induced differences in T-1 were -0.004 +/- 0 .007 sec (mean +/- standard deviation) for white matter and 0.010 +/- 0.015 sec for internal gray matter structures, neither of which was significant. Conclusions: This reasonably sensitive measurement does not support the vie w that tissue water content or water macromolecule interactions are signifi cantly altered in the brain during acute alcohol intoxication in otherwise healthy subjects.