A follow-up study of 91 patients operated on for focal epilepsy.

Ninety-one patients operated on for focal epilepsy between 1952 and 1973 have been followed regularly. Nontumoral lesions were found in 68 patients, and tumors in 23. Of the 50 patients without tumor who have been followed for more than 2 years, 30% were seizure-free, 50% improved, while only 20% did not benefit from the operation. There was no operative mortality. Ventricular asymmetry in the pneumoencephalogram was associated with a better prognosis than when there was no or symmetrical enlargement. The time between the onset of seizures and the operation did not affect the prognosis, but early operation is important to achieve better and quicker rehabilitation. There was a positive correlation between the postoperative ECoG and EEG and the clinical results.