Photosensitive epilepsy beyond adolescence: is freedom from photosensitivity age-dependent?

Patients with photosensitive epilepsy (PSE) are said to lose photosensitivity with age. That is, they do not suffer from photosensitive epileptic seizures after the third decade of life. This claim seems to be an over generalised statement and does not take into account all other important confounding factors that determine the duration and process of neurological illnesses. Hence, there are contradictions pertaining to age of freedom of photosensitivity in epilepsy and in epilepsy with photosensitivity. Often patients are declared free from epileptic activity; however, some of these patients are still found to have seizures a few years later. This paper assesses the freedom photosensitivity in 58 PSE patients to ascertain validity of the claim that patients lose their photosensitivity with age. Thirty-nine of the 58 patients (67%) were female whilst (33%) were male, giving a female/male ratio of 3:1. The average age of onset of photosensitivity was 7 years. Of all the cases studied forty-one (71%) had a family history of photosensitive epilepsy, while seventeen (29%) had no family history of photosensitive epilepsy. Proof of photosensitivity in all the patients was determined by persistent EEG abnormalities including occipital spike and wave discharges. Results show that photosensitivity persisted beyond adolescence; hence, there was no specific age limit of freedom from photosensitivity in patients, especially in those with family history of photosensitive epilepsy. However, those patients who were having regular antiepileptic medication and/or were taking adequate preventive measures had a temporary period of freedom from sensitivity which lasted 1-4 years. These findings suggest that freedom from photosensitivity is not age-dependent, especially in those patients with family history of photosensitive epilepsy.