Fixation-off Sensitivity Research Articles

Early-onset benign occipital seizure susceptibility syndrome.

Childhood epilepsy with occipital paroxysms (CEOP) is characterised by ictal visual hallucinations and occipital epileptiform activity on interictal EEG. A variant has been described with nonvisual symptoms including tonic head and eye deviation, vomiting, and episodes of partial status epilepticus. We fully documented the electroclinical features of such patients to determine whether classification separate from CEOP is justified. This was a multicentre study with participating investigators submitting details of patients with idiopathic occipital seizures characterised by ictal head or eye deviation and vomiting. One hundred thirteen patients were recruited. Seizures began in early childhood (mean, 4.6 years) and occurred infrequently (mean total seizures, 3); 30% of patients had only a single seizure. Two thirds of seizures were nocturnal. Ictal eye deviation occurred in 79%, vomiting in 70%, and head deviation in 35%. Seizures were predominantly complex partial in type. Partial status epilepticus occurred in 44% of patients. Seventy-four percent of patients had occipital interictal EEG epileptiform activity, predominantly right sided, with fixation-off sensitivity. Extraoccipital EEG abnormalities occurred in 35% of patients. Prognosis was excellent: the mean duration of active seizures was 1 year. Although the two groups shared identical EEG features, the distinct clinical symptoms probably justify separate classification. Early-onset benign occipital seizure syndrome (EBOSS) is suggested as an appropriate name for the variant group.

Benign childhood epilepsy with occipital paroxysms: a 15-year prospective study.

Eighteen of 418 children who had onset of epilepsy before the age of 13 years showed clinical and electroencephalographic evidence of benign childhood epilepsy with occipital paroxysms. They represented one-fifth of all benign age- and localization-related idiopathic epilepsies seen. Some patients were followed as long as 15 years. There was a preponderance in females and peak age at onset of epilepsy was 5 years. In 16 children, the seizures were infrequent and sometimes prolonged and consisted mainly of tonic deviation of the eyes and vomiting, often with evolution to unilateral or generalized convulsions. Seizures were only nocturnal in 11 and nocturnal and diurnal in another 5 children. Prognosis was excellent; 5 children had only one fit. Remission usually occurred 1 to 2 years after onset and no seizures occurred after the age of 12 years. The remaining 2 children had frequent diurnal episodes consisting of visual hallucinations, postictal headache, and occasional nocturnal hemiconvulsions. Their prognosis was less favorable. Electroencephalographic abnormalities in all 18 patients consisted of repetitive spike and slow-wave discharges confined to the occipital regions and attenuated when the eyes were open. These outlasted clinical remission for many years, sometimes up to the age of 16. Fixation-off sensitivity was demonstrated frequently. Based on these findings, a unifying definition for benign childhood epilepsy with occipital paroxysms is proposed.