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

Cerebral 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.

Methods

20 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 (vascular territory, type, and visual pathway involvement) and neuropsychological outcomes were analyzed between cohorts using standard statistical comparison methods and linear regression model.

Results

All childhood stroke patients could complete virtual reality visual search tasks 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 correlated with slower reaction time to fixation on a target independent of age, and the presence of attention deficit or other behavioral disorders.

Conclusions

Bedside VR/ET assessment in children affected by stroke can detect signs of HOVP deficits. Imaging demonstrating involvement of the posterior visual pathway at the time of diagnosis strongly predicts development of impaired visual tracking abilities later in life. While detection of CVI and HOVP using current standard clinical and neuropsychological evaluations can be challenging, our study demonstrates that injury pattern on imaging at stroke onset can help identify children at risk of CVI. This can enable early diagnosis and timely accommodations facilitating functional vision development, critical to learning and skill acquisition.