EPISODIC BRAIN-STEM COMPRESSION MASQUERADING AS ELECTRODECREMENTAL SEIZURES

An 8-year-old boy developed generalized tonic spasms lasting minutes a ccompanied by an electrodecremental event on electroencephalogram in a ssociation with increased intracranial pressure caused by shunt malfun ction. The electroencephalographic abnormalities and clinical attacks occurred despite an otherwise normal neurologic examination, normal in itial opening pressure on lumbar puncture and shunt tap, and only mild ventricular dilation revealed by brain There was no improvement with antiepileptic drugs. Further signs of uncal herniation led to repeat t ap of the shunt, revealing a pressure of 800 mm of water. After revisi on of the shunt ''seizures' stopped and the electroencephalogram retur ned to normal. Antiepileptic drugs were discontinued, with no recurren ce of events.