Simple phonic tic in multiple sclerosis.

Movement disorders occurring in association with multiple sclerosis (MS) are rare. Among them paroxysmal dystonia is the most common, although chorea, ballism, palatal myoclonia, spasmodic torticollis, writer's cramp and generalized dystonia have been reported. We describe a 34-year old woman with MS who developed simple phonic tic characterized by throat-clearing sounds. Magnetic resonance imaging showed demyelinating lesions involving the thalamus and basal ganglia. This is the first report of tic disorder occurring as a manifestation of MS.