Fundus Peripapillary Vascular Changes in Autism Spectrum Disorder: A Cross-Sectional Study

In this cross-sectional study, participants were recruited through convenience sampling from the Children's Mental Health Research Center at The Affiliated Brain Hospital of Nanjing Medical University and the Department of Ophthalmology at The First Affiliated Hospital of Nanjing Medical University, Nanjing, China, between December 2019 and October 2024. A total of 200 eyes were ultimately enrolled in this study, sourced from 53 individuals with ASD, aged between 7 and 13 years, and an equal number of age- and sex-matched neurotypical (NT) controls. The aim of this research is to explore the changes in retinal and choroidal vasculature in children with ASD, evaluated through optical coherence tomography and its angiography, and to further investigate the potential value of retinal vascular characteristics in the auxiliary screening and diagnosis of ASD. We analyzed intergroup differences in perfusion density (PD), vessel density, flux index (FI), fractal dimension (FD), and vessel diameter (Dm) in the peripapillary region, further stratified by subquadrants and vessel types. The results show that ASD children exhibited significant differences compared to neurotypical controls, including increased PD and Dm in the supero-nasal quadrant (p < 0.01), changes in capillary FI in the nasal quadrant (p = 0.008), increased venous FD (p = 0.009), and abnormal choroidal FI in the temporal quadrant (p = 0.008). A random forest classification model constructed based on these key features demonstrated promising performance (AUC = 0.7853) in distinguishing ASD from NT individuals, highlighting the potential of retinal vascular characteristics for auxiliary ASD screening. Moreover, retinal vascular parameters were significantly correlated (p < 0.01) with blood oxygen level-dependent signals from functional magnetic resonance imaging in several brain regions, such as the amygdala (p = 0.004-0.009) and temporal lobe (p = 0.000-0.009). Further stepwise regression analysis indicates that key retinal vascular characteristics could partially predict core clinical features of ASD, such as social functioning (adjusted R ²  = 0.091-0.104, quantified by total and subscale scores of Social Responsiveness Scale) and cognitive ability (adjusted R ²  = 0.2785, quantified by total intelligence quotient scores). This study underscores the potential of retinal vascular features as biomarkers for ASD and provides a basis for future research on non-invasive retinal imaging-based approaches for ASD screening and diagnosis, while offering new perspectives for understanding the pathological mechanisms and clinical applications of ASD.