Sleep abnormalities in four cases of dyssynergia cerebellaris myoclonica of Ramsay-Hunt.

The nocturnal sleep of four patients with dyssynergia cerebellaris myoclonica (DCM) of Ramsay-Hunt was recorded with a polygraph. The following features were observed: a reduction of spindles, K complexes and vertex spikes; frequent arousals; rare rapid eye movements with a modification of their morphology and pattern; change in sleep stage percentages. In addition, myoclonus and polyspike-and-wave complexes appeared less frequently during sleep than during wakefulness. Three generalized convulsive and sixteen clonic seizures were recorded during stage 3/4 or on arousal. The clinical and physiopathological implications of these data are discussed.