Vision In SyndrOmic Neurodevelopmental disorders-15q (VISiON-15q) study: eye tracking to supplement clinical examination for detection of cerebral/cortical visual impairment in children with Angelman and Duplication of 15q Syndromes.

Abstract

Purpose: To identify children with Angelman syndrome (AS) and Duplication of 15q (Dup15q) syndrome who have cerebral/cortical visual impairment (CVI) using clinical examination combined with eye tracking.

Design: Prospective cohort study.

Participants: Twenty-five children (12 months to 12 years old) with AS and Dup15q syndrome, collectively termed 15q disorders.

Methods: All participants underwent complete pediatric neuro-ophthalmologic evaluation, including assessment of visual acuity using the Visual Behavior Scale (VBS) and Teller acuity cards. The Higher Visual Function Question Inventory (HVFQI) was administered to assess parental report of behaviors suggestive of CVI. Eye tracking was performed in participants who were able to complete accurate calibration. Participants were also administered the Mullen Scales of Early Learning (MSEL) Visual Reception scale, as well as non-visual subscales. Parents completed the Vineland Adaptive Behavior Scales, 3^rd ed. (VABS-III) and Children's Visual Function Questionnaire (CVFQ) to measure adaptive function and vision-specific quality of life, respectively.

Main outcome measures: Proportion of participants classified as having diagnosis or high suspicion of CVI (15q-CVI-DHS) based on multimodal visual assessments; association between CVI status and MSEL, VABS-III, and CVFQ scores.

Results: 15 of 25 (60%) of 15q participants were classified as 15q-CVI-DHS. Of these, 6 (40%) were classified based on eye tracking alone. Compared to children with low suspicion of CVI, children in the 15q-CVI-DHS group had lower MSEL visual reception (17.6 ± 12.4 vs. 43.9 ± 25.7, p = 0.024), fine motor (21.3 ± 14.1 vs. 38.6 ± 20.6, p = 0.044), and verbal (15.0 ± 13.6 vs. 38.8 ± 28.0, p = 0.035) developmental quotients. Children in the 15q-CVI-DHS group also had lower CVFQ scores (overall 0.60 ± 0.18 vs. 0.82 ± 0.10, p = 0.022), without significant differences in VABS-III composite or domain scores.

Discussion: Children with 15q disorders had a high rate of CVI or CVI suspect diagnosis, which was detected by eye tracking alone in 40% of cases. CVI was associated with worse vision-specific quality of life and lower developmental scores on multiple non-visual domains in these children. Future studies are needed to substantiate these findings in a larger cohort and characterize differences between genetic subtypes.