Photic induced-driven PLEDs in paroxysmal dystonic choreoathetosis.

An 82-year-old female had rare unilateral spontaneous attacks of paroxysmal dystonic choreoathetosis without loss of consciousness since early adolescence. Her maternal aunt had similar episodes. Previous interictal EEGs never recorded in close association to her attacks had been normal. Photic stimulation at low frequencies during EEG recordings performed near to one of her ictus, induced paroxysmal driven lateralized epileptiform discharges from the contralateral hemisphere. This peri-ictal finding in a patient with paroxysmal dystonic choreoathetosis is unique and suggests this disorder may have some epileptogenic basis.