Involvement of the Posterior Visual Pathway Correlates with Higher-Order Visual Impairment in Childhood Stroke Patient

Background/ObjectiveCerebral injury due to stroke in childhood increases the risk of higher-order visual processing (HOVP) deficits, like cerebral visual impairment (CVI), which can lead to severe behavioral and learning disabilities if left untreated. Using a virtual reality-based search task and structural Magnetic Resonance Imaging analysis, we assess the extent of functional vision deficits in childhood stroke patients and potential anatomical correlates. Methods20 childhood stroke patients and 38 healthy controls completed a dynamic visual search task using a virtual reality/eye-tracking (VR/ET) paradigm to quantify functional vision abilities between 2021 to 2024 (average 7.34 years after stroke). Virtual reality assessment measures, stroke imaging characteristics (visual pathway involvement) and neuropsychological outcomes were analyzed between cohorts using statistical comparison methods and linear regression model. ResultsAll childhood stroke patients could complete the VR/ET task, whose metrics were associated with neuropsychological testing measures of visual attention and processing speed, as demonstrated by success rates and task compliance in equal measure to controls. However, less accurate search and slower fixation rates together with less sensitivity to changes in task load and greater impairment in initiating a response to a target were observed in our patient cohort. On MRI lesion analysis injury involving the posterior visual pathways, specifically the optic radiations, inferior longitudinal fasciculus, or superior longitudinal fasciculus, correlated with slower reaction time to fixation on a target when controlling for age at time of VR testing. ConclusionsBedside VR/ET assessment in children affected by stroke can detect signs of HOVP deficits as confirmed by neuropsychological testing. Imaging demonstrating involvement of the posterior visual pathway at the time of diagnosis is strongly correlated with development of impaired visual tracking abilities later in life. While detection of HOVP deficits relies on current standard clinical and neuropsychological evaluations between 3 to 6 years of age, our study demonstrates that injury pattern on imaging at stroke onset can help identify children at risk of HOVP deficits. This may enable early monitoring and timely accommodations facilitating functional vision development, critical to learning and skill acquisition.