Seeing the Unseen: The Neurodevelopmental Factors Related to Visual Impairments in Children With Unilateral Cerebral Palsy

Abstract

Background: In children with unilateral cerebral palsy (uCP), the relation between different factors (brain damage, prematurity, and cerebral palsy side) and visual impairments, which are common but often 'unseen,' is not fully understood. Methods: Visual functions and functional vision were assessed in 41 children with uCP (7-15 years, 21 left-sided, 19 preterm). Brain damage was scored on structural magnetic resonance imaging regarding lesion timing, location, and severity, and corpus callosum (CC) length and splenium thickness. With nonparametric statistics, we investigated the relation between visual outcomes and brain damage (r(s) ) and differences in visual outcomes and brain damage based on prematurity and uCP side (r). With elastic-net regularized regression models (area under the receiver operating characteristic curve [AUC]; d), we explored if gestational age and brain damage could predict impairments in visual functions. Results: Damage to the lobes and CC was associated with reduced visual functions and functional vision (r(s) = -0.402 to -0.611). Compared to children born at term, preterm children mainly showed reduced geniculostriate functions (r = 0.343-0.443) and damage to the parietal lobe (r = 0.353). No differences in brain damage were found between children with left- and right-sided uCP. In regression models, shorter CC length and parietal lobe lesion (d = -0.526 to 0.564) were the main predictors for impaired stereoacuity (AUC = 0.77), and occipital lobe lesion (d = 0.349) for impaired visuomotor integration (AUC = 0.81). Prediction models of visual perception showed poor predictive performance (AUC<0.70). Conclusions: Specific brain damage and prematurity are related to different visual impairments in children with uCP. Our results could guide clinicians in directing their attention to specific visual assessments and subsequent intervention in children with uCP.