Brainstem function in rapid eye movement sleep behavior disorder: The evaluation of brainstem function by proton MR spectroscopy (H-1-MRS)

Brainstem function was evaluated by proton magnetic resonance (MR) spectros copy (H-1-MRS) in a 69-year-old man with idiopathic rapid eye movement (REM ) sleep behavior disorder. An analysis of spectral peak area ratios reveale d an increase in the choline/creatine ratio. This change suggests that brai nstem neurons have functional impairment at the cell membrane level. Furthe r, our results suggest that H-1-MRS may provide for non-invasive, metabolic evaluation of brainstem neuronal function in REM sleep behavior disorder a nd find application in the differentiation of secondary REM sleep behavior disorders with neurodegenerative disorders from idiopathic disorders.