Sacrificing One Visual Hemifield during Pediatric Epilepsy Surgery: Effects on Visual Search

Purpose: To investigate early and late effects of planned surgically acquired homonymous hemianopias on visual search in children and adolescents.

Methods: This prospective study included five patients (5 years 5 months–18 years 0 months; 2 girls) in whom one visual hemifield was sacrificed as part of the surgical strategy, and, as controls, seven patients (5 years 11 months–18 years 0 months; 6 girls) undergoing epilepsy surgeries not affecting the visual fields. Visual search was studied using the “Table Test,” which is an everyday life-like visual search test. Processing speed was studied using standard IQ subtests.

Results: All five patients with newly acquired homonymous hemianopias showed a relative disadvantage of visual search times for objects in their newly blind hemifields immediately after the surgery. Six months later, this relative disadvantage had recovered completely in all patients. Nevertheless, compared with the preoperative situation, overall search times were still prolonged in the hemianopic patients, but this effect could be mitigated or even overcompensated by improvements in processing speed.

Conclusion: Children with homonymous hemianopias inflicted by epilepsy surgery develop effective compensation strategies to minimize the relative disadvantage of visual search in their blind hemifields. For changes in overall visual search times between the preoperative and the 6-month follow-up examination, we could demonstrate overlapping effects of (1) deterioration by hemianopia and (2) amelioration by improved processing speed as part of the cognitive improvements achieved by amelioration of the epilepsy.

Publication History

Article published online:
28 October 2021