Thirty seven chidren who met the diagnostic criteria for early-onset benign occipital seizure susceptibility syndrome (BOSSS) were followed prospectively for more than two years at the Tokyo Women’s Medical University and Doaikai Hospital, Tokyo, Japan. This diagnosis accounted for 11.7% of children with localization-related epilepsy, who developed a first seizure before 13 years of age, and presented at one of two seizure clinics between 1989 and 1998. Diagnostic criteria employed were as follows: 1) normal development before seizure onset; 2) onset 1 to 8 years of age; 3) normal MRI or CT; 4) ictal vomiting and tonic eye-deviations; 5) normal EEG background activity with or without epileptic foci regardless of location. The Panayiotopoulos criterion of occipital EEG paroxysms was excluded, since EEG foci often shift to centrotemporal or frontal regions (Ferrie et al 1997; Oguni et al 1999). In this series initial EEG spike foci were occipital in 26 (70%), 17 of whom later revealed a shift in location, extraoccipital in 19%, and were absent in 11%. At final follow-up, only 43% foci were occipital, 46% extraoccipital, and absent in 11%. A family history of epilepsy was identified in 12 patients (32%), including a family with 2 children having BOSSS. Febrile convulsions preceded onset of BOSSS in 14 (38%). Total number of BOSSS seizures was 1 - 27 (median 5). Status epilepticus occurred in 22 (59%). Remission for longer than 2 years was achieved in 28 (76%); and 80% of these remitted by 3 years after onset. Antiepileptic drugs had been discontinued in 21 (57%). Fifteen children (40%) with recurrent prolonged seizures, initially refractory to AEDs, had an earlier onset and more frequent complications. Seizures remitted by 12 years in all cases. [1]

COMMENT. The clinical features of early-onset BOSSS vary from a single or occasional seizure to cases with recurrent prolonged seizures, initially AED resistant, and even status epilepticus in more than half the patients, despite ultimate remission by 12 years of age. Patients with prolonged seizures, initially resistant to AED, are recognized by an earlier onset and more frequent complications (prematurity with asphyxia, neonatal seizure, borderline IQ). The authors propose that the term occipital be removed from the terminology, since patients meeting all other criteria for BOSSS may have extraoccipital EEG spike foci or sometimes no EEG epileptic foci.