A mother and son suffer from hemiplegic
migraine with onset in childhood. Both have nystagmus which has not changed for many years, but the date of onset is uncertain. They have an asymmetrical
tremor, clinically indistinguishable from
essential tremor. Neuroophthalmological examination revealed inability to produce smooth pursuit, gaze-paretic
nystagmus, rebound nystagmus, failure of fixation suppression of the vestibuloocular reflex both horizontally and vertically, and low gain of the optokinetic system. These abnormalities, confirmed by electrooculography, are commonly seen in disease of the cerebellum and brainstem. Treatment with
propranolol and
pizotyline lessened the number of episodes of
hemiplegia and improved the
tremor. Hemiplegic
migraine has been reported in association with nystagmus,
retinal degeneration,
deafness, and
ataxia in varying combinations in three other families with autosomal dominant inheritance. These associated
neurological manifestations likely represent system degenerations rather than the effect of repeated
ischemia imputable to the
migraine itself. The syndrome of hemiplegic
migraine,
tremor, and ocular smooth pursuit system disorder seen in this family appears to be inherited as a single autosomal dominant trait, although more than one autosomal dominant gene may be involved.