Affiliations: Department of Pediatrics, Faculty of Medicine, University of Yamanashi, Yamanashi, Japan | Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan
Note:  Corresponding author: Hideaki Kanemura, Department of Pediatrics, Faculty of Medicine, University of Yamanashi, 1110 Chuo, Yamanashi 409-3898, Japan. Tel.: +81 55 273 9606; Fax: +81 55 273 6745; E-mail: firstname.lastname@example.org.
Abstract: Epilepsy with continuous spike-waves during slow sleep (CSWS) is characterized by impairment of neuropsychological abilities, frequently associated with behavioral disorders. These manifestations strongly correlate with frontal lobe dysfunctions. CSWS in childhood may affect the prefrontal cortex and leave residual mental and behavioral abnormalities as profound and permanent as the loss of speech in Landau-Kleffner syndrome. In our previous volumetric studies, frontal and prefrontal lobe volumes revealed growth disturbance in all CSWS patients compared with those of normal subjects. These studies also revealed that in the patients with shorter seizure durations and CSWS periods, developmental abnormalities of the prefrontal lobes were soon restored to a more normal growth ratio, whereas growth disturbances of the prefrontal lobes were persistent in the patients with longer seizure durations and CSWS periods. These findings suggest that seizure and the duration of paroxysmal anomalies may be associated with prefrontal lobe growth abnormalities, which are associated with neuropsychological problems. Thus, the duration of CSWS period seems to be a significant prognostic factor. The urgent suppression of this electroencephalography abnormality may be necessary to prevent the progression of neuropsychological impairments. The best treatment options may be required to remit seizures and electroencephalography abnormalities as soon as possible to achieve optimal prognosis in CSWS.