(1)H-MR spectroscopy indicates prominent cerebellar dysfunction in benign adult familial myoclonic epilepsy

PURPOSE: To investigate the neurochemical pattern in patients with benign adult familial myoclonic epilepsy (BAFME/FAME), an inherited form of myoclonic epilepsy, by proton magnetic resonance (MR) spectroscopy ((1)H-MRS). METHODS: Eleven BAFME patients from three families showing linkage to 2p11.1-q12.2 were compared with 11 age-matched healthy control subjects. RESULTS: MR imaging of all the patients and healthy subjects exhibited no structural abnormalities on detailed visual assessment. However, compared with healthy subjects, patients with BAFME displayed elevated choline/creatine ratio in the cerebellar cortex (p = 0.01), whereas there was no significant difference for the other ratios. No (1)H-MRS values in the frontal and occipital cortex differed significantly in the patients compared with the healthy controls. No correlation was detected between (1)H-MRS values and disease duration (p = -0.35) as well as myoclonus severity (p = -0.48). CONCLUSIONS: Our findings suggest that the cerebellum is a prominent site of dysfunction in BAFME. The abnormal choline concentrations could reflect changes in the chemical and functional nature of cell membranes. (1)H-MRS was able to detect brain changes also in patients with recent disease onset and may be a useful tool supporting the diagnosis based on familial and electrophysiologic data. The relationship between cortical tremor and the cerebellum is also discussed.