Prefrontal lobe growth in a patient with continuous spike-waves during slow sleep.

Epilepsy with continuous spike-waves during slow sleep (CSWS) is characterized by impairment of neuropsychological abilities, frequently associated with behavioral d isorders. These manifestations strongly correlate with frontal lobe dysfunctions. In the present case, an 11-year-old girl presented with progressive behavioral deteriorations after the appearance of electrical status epilepticus in sleep. The duration of CSWS period was 5 months. Serial measurements (at the appearance of the EEG pattern, and 6 months and 1, 2, 3 and 4 years thereafter) of frontal and prefrontal lobe volumes by 3-dimensional magnetic resonance imaging-based volumetry showed growth disturbance of prefrontal lobe volume, particularly prefrontal-to-frontal lobe volume ratio, after the appearance of the EEG pattern when compared with two frontal lobe epilepsy subjects without neuropsychological disorders and 13 control subjects. However, the ratio was restored to the growth ratio and seen to reach control levels, after improvement of the clinical manifestations of CSWS. These results suggest that children with CSWS may be prone to frontal lobe dysfunctions, and that the duration of CSWS period seems to be a significant prognostic factor. The urgent suppression of this EEG abnormality may be necessary to prevent the progression of neuropsychological impairments.