Serial T2-weighted magnetic resonance imaging in a 29-year-old woman with juvenile type dentatorubral-pallidoluysian atrophy (DRPLA) demonstrated that a cerebral white matter hyperintensity appeared within 2 months after status epilepticus and persisted for more than 20 months. The patient had rapidly progressive mental regression and became akinetic after status epilepticus. The chronological relationship between the signal changes and the clinical deterioration suggested that the epilepsy, at least in part, contributed to the progression of white matter degeneration, the hallmark of DRPLA.