Prevalence of Vision and Eye Movement Abnormalities in Children Referred to the Children's Epilepsy Surgery Service: A 5-Year Observational Study

Purpose:
To report the prevalence of visual acuity, visual field, and ocular motility problems in children with epilepsy referred to the Children's Epilepsy Surgery Service (CESS) for surgery.

Methods:
This was a retrospective observational study of all children referred to the CESS in Bristol between 2015 and 2020. Data extraction included age, age at epilepsy diagnosis, epilepsy etiology (as determined by seizure semiology, neuroimaging, and electroencephalography), anti-seizure drugs, visual acuity, visual field, ocular motility, and fundus imaging.

Results:
A total of 221 children with epilepsy were seen during the study period: 60% (132/221) had structural etiologies, 8% (18/221) were genetic, and in 28% (62/221) the etiology was unknown. Overall, 53% (117/221) were found to have abnormalities, particularly strabismus (16%, 36/221), visual field defects (14%, 27/198), and reduced visual acuity (12%, 26/219). Notably, 54% (63/117) of children with ophthalmic abnormalities were new diagnoses in the CESS clinic. Younger children and those with neurodevelopmental disorders were less likely to complete all vision tests.

Conclusions:
Ophthalmic abnormalities were prevalent among children referred for epilepsy surgery in Bristol and more than half were previously undiag-nosed. The data support the adoption of an orthopticled vision screening service for children with medically refractory epilepsy, structural etiologies, and focal seizures, to better support their needs in the community.