Nocturnal paroxysmal dystonia related to a prerolandic dysplasia

Nocturnal paroxysmal dystonia (NPD) is a rare disorder characterized by attacks of short-lived dystonic, tonic, and choreoatetoid movements occurring mainly during sleep. Although seizures are believed to arise from the frontal lobe, their localization is, however, uncertain due to the lack of ictal clinical-electroencephalogram (EEG) correlations. We report two patients with episodes clinically compatible with NPD who also experienced occasional generalized tonic-clonic seizures in which there was a frontal (prerolandic) dysplasia detected by magnetic resonance imaging (MRI). In one patient interictal/ictal single photon emission computed tomography (SPECT) suggested that the seizure focus was over the area of dysplasia. Both patients support the notion that this type of epilepsy is a form of frontal lobe epilepsy, possibly originated in the prerolandic region.