Benign childhood occipital epilepsy, Gastaut type. Late onset benign childhood occipital epilepsy. Benign epilepsy of childhood with occipital paroxysms (BECOP).
Incidence
This disorder is a rare form of epilepsy which accounts for 2 to 7% of benign childhood focal seizures. Males and females are equally affected. Autosomal dominant.
Clinical Characteristics
It is an idiopathic form of epilepsy, which manifests with frequent visual seizures of elementary visual hallucinations, blindness or both. The seizures can occur daily or weekly and occur usually during the daytime lasting from seconds to 3 minutes. Visual hallucinations are the most common symptom. Other occipital symptoms such as sensory illusions of ocular movements and ocular pain, tonic deviation of the eyes, eyelid fluttering, or repetitive eye closures may also occur. Complex visual hallucinations may progress to hemiconvulsions or generalized convulsions. Consciousness is intact during the visual symptoms but may be disturbed or lost if the seizures progress to other symptoms and convulsions. Postictal headache, sometimes indistinguishable from migraine headache, often occurs in one-third of the patients. It is considered an epileptic syndrome. There may be an increased family history of epilepsies or migraines. About one third of children have a family history of epilepsy and some children have had seizures with feverish illnesses (febrile convulsions) before starting to have BECOP. The EEG has paroxysms of high-amplitude spike waves or sharp waves recurring rhythmically on the occipital and posterior temporal areas of one or both hemispheres, but only when the eyes are closed. During seizures the occipital discharge may spread to the central or temporal region. Prognosis is unclear. However, current data may indicate that remission occurs in more than 60% of patients by late teens. Most of the cases (90%) respond well to Carbamazepine.
Precipitants
Sleep deprivation can trigger seizures. Some children may have seizures as they go from a dark area into a brighter one, or from a well lit area into a dark one.
Provocation Tests
EEG is mandatory to make the diagnosis. All other tests are normal.
Diagnostic Procedures
It is a clinical-EEG diagnosis. EEG is mandatory to make the diagnosis. All other tests are normal.