Reorganization of the primary somatosensory area in epilepsy associated with focal cortical dysplasia

A 5-year-old boy with focal cortical dysplasia was referred to our hospital because of epileptic seizures. He showed mild weakness of the left hand wi thout sensory disturbance. Brain MRI revealed extensive cortical dysplasia with pachygyria and microgyria around the right central sulcus. On EEG exam ination, interictal spikes were noted over the right fronto/centro/parietal region. A 37-channel magnetometer revealed that the sources of the spikes were in a small, restricted region of the normal frontal lobe adjacent to t he dysplastic brain. Somatosensory evoked magnetic fields indicated that th e location of the current source of N20 was in the same area. Our patient s hows a unique case of plasticity and reorganization of the somatosensory fu nction due to cortical dysplasia.