In occipital lobe epilepsy, seizures arise from the occipital lobe of the brain, which sits at the back of the brain, just below the parietal lobe and just behind the temporal lobe. The occipital lobe is the main center of the visual system. Occipital lobe epilepsy accounts for about 5-10% of all epilepsy syndromes. This kind of epilepsy can be either idiopathic (of unknown, presumed genetic, cause) or symptomatic (associated with a known or suspected underlying lesion). Benign occipital epilepsies usually begin in childhood and are discussed elsewhere.
Occipital seizures usually begin with visual hallucinations like flickering or colored lights, rapid blinking, or other symptoms related to the eyes and vision. They may occur spontaneously but can often be triggered by particular visual stimuli, such as seeing flashing lights or a repeating pattern. Occipital seizures are often mistaken for migraine headache because they share similar symptoms including visual disturbances, partial blindness, nausea and vomiting, and headache.
The following are the different types of seizure symptoms associated with occipital lobe seizures:
As with any epilepsy syndrome, detailed patient history, neurological examination, and EEG are very important. In occipital lobe epilepsy, the EEG may provide information that is very helpful in making the correct diagnosis. An abnormal response in the EEG to intermittent photic stimulation (rapidly flashing strobe light) often occurs in occipital lobe epilepsy. However, this response can occur in other epilepsy syndromes as well.
Treatment with a drug used for partial epilepsy, often carbamazepine, is usually effective. In intractable cases (those that do not respond to medication), surgical options may be considered.