In contrast to postmortem studies, in vivo magnetic resonance (MR) modalities constitute safe, noninvasive methods for longitudinal examination of the condition of the brain in patients with alcoholism during the natural course of chronic alcohol consumption, detoxification, abstinence or relapse. Such MR studies have demonstrated that some structural brain changes are reversible with prolonged abstinence from alcohol.72,80–82 Indeed, ARBD may have two components, one of which is transient and the other being permanent.83 If brain volume loss is due to neuronal loss, brain volume recovery will be incomplete with abstinence. For example, some MR spectroscopy studies have shown that in spite of prolonged abstinence, individuals who have chronically consumed alcohol demonstrate persistent N-acetylaspartate (a putative marker of neuronal integrity) decreases in the frontal lobes,84–86 the thalamus86 and the cerebellum.86,87 Other studies, however, have found improvements in the levels of N-acetylaspartate and choline—another metabolite that may indicate remyelination—with abstinence.88–90 Structural repair of myelin could explain the increase in white matter volume that has been shown to occur after periods of abstinence from alcohol.91–93
