Early onset benign occipital susceptibility syndrome: video-EEG documentation of an illustrative case.

Early onset benign occipital susceptibility syndrome (EBOSS) is a recently delineated form of idiopathic childhood partial epilepsy, which is still not recognized by the International League Against Epilepsy as a distinct epileptic syndrome. It occurs with generally nocturnal, prolonged partial seizures, which can become a status epilepticus. The seizures are characterized by tonic eye deviation, vomiting, progressive impairment of consciousness, autonomic symptoms, frequent progression to hemiconvulsions or generalized tonic-clonic seizures. Age at onset is usually between 3 and 7 years, frequency is remarkably low (often a single seizure), and outcome is excellent. Interictal EEG shows occipital paroxysms with fixation-off sensitivity. We present the first video-EEG documentation of a typical case of EBOSS and discuss the clinical and EEG features of the case. The documentation is useful for a better definition of the syndrome and also permits a differential diagnosis with respect to other occipital forms of epilepsy and other sleep related paroxysmal disorders.