Early years examination to identify suspect cerebral visual impairment (EYE-CVI): a feasibility study

Abstract

Objective: Early identification of cerebral visual impairment (CVI) is important in providing timely educational support. This study explores the feasibility of early years teachers (EYT) administering in-nursery assessments of visual function.

Methods and analysis: EYT within six nursery settings were recruited and underwent training and supervision in visual acuity and tablet-delivered visuoperceptual testing (children's visual impairment test; CVIT 3-6). Binocular visual acuity was recorded at 1.5 m and 33 cm. A crowding ratio was calculated if visual acuity was poorer than 0.3 logMAR. Engagement scores were completed to offer insights into areas of testing children found easiest/hardest to engage with.

Results: Four nursery settings completed training and the families of 37 children aged 3-4 years consented to participate; 97% of participants completed acuity testing (mean testing time 5 min) and 86% participants underwent CVIT 3-6 testing (mean testing time 15 min). Mean CVIT 3-6 score was 54.6/70, (expected 10th centile score for age=53). Only 55% children completed all 14 CVIT 3-6 domains. The subtests with poor performance in all three areas (pass rate, completion rate and engagement score) were 'structure from motion', 'missing part' and 'coherent motion'.

Conclusion: Training EYT to administer visual function testing is feasible, in that some elements can be conducted in all children with a reasonably short test time. Further studies are required to identify which visuoperceptual testing domains offer the highest sensitivity/specificity for CVI-related visual dysfunction in this age group.

Keywords: Child health (paediatrics); Vision; Visual (cerebral) Cortex; Visual perception.

Figure 1. Sample images from CVIT3–6 testing protocol. CVIT 3–6, children’s visual impairment test.

Figure 2. CVIT 3–6 scores by participant showing age-corrected expected score (where skipped domains score 0). CVIT 3–6, children’s visual impairment test.