Seventeen patients treated for hemiplegic epilepsy by hemispherectomy between 1950 and the present day have been followed up at the National Centre for Children with Epilepsy, The Park Hospital for Children, Oxford. The causes of the seizures were associated with perinatal complications in 8 and early febrile status epilepticus, prolonged and unilateral, in 9. Two of the 17 had congenital abnormalities: Sturge-Weber disease in one and a heterotopia found at operation in the other. Habitual seizures began at age 1 to 10 yrs after an interval of relative freedom varying from 8 mos to 10 yrs. - Gross behavior disorder was a major handicap, schooling was interrupted, and intelligence deteriorated in the years before operation. EEG was of limited value, both hemispheres often being involved. High-voltage discharges occurred in the preserved hemisphere. The median age at operation was 11^ yrs (7-17 yrs). Follow-up ranged from 1-36 yrs.

Post-operatively, (1) habitual epilepsy was interrupted with complete freedom in 11 (65%); (2) behavior improved, sometimes dramatically; (3) drop in IQ was halted; (4) the residual homonymous hemianopia was not a major handicap; and (5) one patient developed hemosiderosis of the postoperative cavity and died 11 years after operation.

The authors make the following recommendations: (1) establish that the lesion is unilateral and medication has been tried fully, (2) weigh dangers of status epilepticus, escalating behavior disorder, and deterioration of IQ when operation is delayed compared to benefits and low risks of early surgery; (3) use improved operative techniques with dissection of cortex in single piece (Falconer and Rushworth) and reconstruction and closure of cavity (Adams), and (4) regular follow-up with CT scans. [1]