[Childhood-onset epileptic blindness--clinical correlates and outcomes]

Acute blindness is a rare presentation of epileptic disorders referring to loss of sight without loss of consciousness corroborating with epileptic discharges recorded on the EEG. We summarized the pertinent literature on childhood-onset epileptic blindness. We also report on our overall experience with 26 children having developed epileptic amaurosis. This includes descriptions of the associated seizures. EEG abnormalities and reports on the response to anti-epileptic therapy as regards to resolution of blindness and control of associated seizures.

Our data for children with epileptic blindness is similar to previous reports regarding the reported duration of blindness and associated seizures, as well as the overall response to therapy and outcome. In our study, 25 children experienced acute episodes of complete visual obscuration lasting for 1-10 minutes and one 4-month-old infant had blindness from birth, representing status epilepticus amauroticus. Ten patients had accompanying generalized seizures, with a photosensitive response recorded in three cases. All of these children were treated with valproic acid regaining full vision and eight became seizure free. Ten children had accompanying focal motor seizures and unilateral temporo-posterior epileptic discharges recorded on EEG and two additional cases had isolated blindness and focal discharges. All 12 children were treated with carbamazepine, regaining full vision and complete seizure control in eleven. One infant with status epilepticus amauroticus since birth, secondary to a persistent epileptic focus over the right central-posterior areas, regained full vision following resection of an area of cortical dysplasia at the age of 8 months. Four additional children had the constellation of migraine headaches, focal motor seizures and complete blindness along with occipital EEG discharges, compatible with the syndrome of late-onset benign childhood epilepsy with occipital paroxysms (Gastaut syndrome). They were treated with carbamazepine and all became asymptomatic within a period of 1-4 years.

Analysis of the literature, in addition to our overall experience, indicates that epileptic blindness in children is associated with a favorable outcome providing prompt diagnosis and treatment of the associated seizures or epileptic syndrome. This resulted in complete and long-standing resolution of blindness in all children together with satisfactory control of seizures. As such, we recommend a prompt EEG in any child presenting acute visual obscuration, even in the absence of additional overt epileptic phenomena.