Limitations in the Medical Treatment of Cryptogenic or Symptomatic Localization‐Related Epilepsies of Childhood Onset

We retrospectively examined 169 patients who had cryptogenic or symptomatic localization‐related epilepsies (LRE) and were followed‐up for more than 5 years. The probability of seizure control was 0.13 during the first year of treatment, 0.25 during the first 5 years, and 0.09 during the second and third 5 years. No patients who continued to have intractable seizures for 15 years became free of seizures. The onset of LRE at the age of 3 years or less, seizure cluster, mesial temporal sclerosis (MTS), and temporal lobe epilepsy (TLE) were significantly associated with a poor seizure control. If an antiepileptic drug (AED) failed to control seizures, probability of seizure control by the next drug was low, in particular in patients in whom more than 4 AEDs have already been tried, and seizure control could not be expected after a trial of 6 AEDs. A tentative indication of epilepsy surgery for LRE of childhood onset may be 5 years of poor seizure control and/or failure of four AEDs.