Unilateral left brain lesion causing generalized seizures

This 18-month-old first presented with seizures at age five months; the seizures progressed to infantile spasms by age 7 months. The infantile spasms were successfully treated with ACTH, but other partial and generalized seizures occurred, including sudden tonic events that affected the right body more than left and lasted 10 to 15 seconds with a frequency of more than 30 times per day. At 18 months, the child was not walking or talking. Neurologic examination showed a right hemiparesis. Scalp EEG showed bilateral but more left than right hemisphere interictal EEG spikes and polyspikes with greater background slowing over the left hemisphere. Ictal events appeared generalized over both hemispheres. Left hemispherectomy was offered because of evidence of progressive epilepsy-induced encephalopathy, and there was no expected increase in neurologic deficits because of surgery. This child has remained seizure-free for more than 10 years after surgery and is now able to walk, talk, and participate in school activities. This case exemplifies how young children often require large resections in order to obtain seizure control and improve cognitive development. (Contributed by Dr. Gary Mathern.)