[Reflex epilepsies]

Reflex seizures are provoked by a specific sensory stimulus. Approximately 6% of all epileptic patients have reflex seizures. For identification of these seizures it is necessary to take a directed history and make an EEG study whilst the patient is being exposed to the stimulus, which will confirm the diagnosis.

Many stimuli are effective in provoking reflex seizures, the commonest are visual. Amongst the various epileptic syndromes there are different types of epilepsies with reflex seizures which generally correspond to idiopathic generalized epilepsies. The physiopathogenic mechanisms are usually complex. The cerebral cortex corresponding to the function which induces the epileptic crisis is hyperexcitable, and is the cause of an identifiable lesion or dysfunction without an underlying lesion.

The diagnostic importance of reflex seizures is that when some formerly drug-resistant patients can control the mechanism which triggers off their seizures they attain good control of them.