Abstract
Purpose :
To compare visual acuity of 6 and 12 month old infants admitted to Neonatal Intensive Care Unit (NICU) with an age-matched control sample.
Methods :
The Neonatal Vision Study (NVS) recruited a sample of 66 infants from the Royal Prince Alfred Hospital NICU, Sydney Australia, with ocular examination performed at 3, 6 and 12 months old. An age-matched control sample of 360 infants was identified from the Sydney Paediatric Eye Disease Study (SPEDS). These infants were born >36 weeks gestation, birth weight >2500g and no history of admission to NICU. Infants in both studies received vision testing on Teller Acuity Cards (TAC), orthoptic assessment for binocular function and ocular alignment, and screening for ocular pathology by ophthalmoscopy. Questionnaires provided information on demographics, maternal health, and the infant’s general health. Ethics approval for NVS was obtained from the Sydney Local Health District Human Research Ethics Committee (HREC) and ratified by University of Technology Sydney HREC. Ethics approval for SPEDS was obtained from the University of Sydney HREC.
Results :
At 6 months old NVS infants had a lower mean gestational age (32.55 weeks) and birth weight (1792.02g) compared to the SPEDS comparison group (39.59 weeks and 3462.43g, all p<.0001). At 12 months of age, the NVS infants also had a lower mean gestational age (32.41 weeks) and birth weight (1785.41g) compared to the SPEDS group (39.35 weeks and 3503.94g, all p<.0001). There were no differences in gender distribution (p=0.94). At 6 months there was a lower mean binocular TAC score of 4.97cpd±2.16 in the NVS infants admitted to NICU compared to the SPEDS infants 6.11cpd±2.18 (p=0.002). Although mean right eye monocular TAC scores between the NVS infants (4.65cpd±2.10) and SPEDS infants (5.43cpd±2.49), were comparable (p=0.052). By 12 months old, binocular TAC scores of NVS infants (14.46cpd±7.32) were significantly higher than the SPEDS comparison group (6.61cpd±2.58, p<.0001). The right eye monocular TAC scores were also higher in NVS infants (12.58cpd±7.58) compared to SPEDS infants (5.34cpd±2.18, p<.0001).
Conclusions :
Infants admitted to NICU in the NVS study had a lower binocular TAC score at 6 months. However, development of vision improved significantly by 12 months and exceeded age matched norms in the SPEDS study. These findings are important to consider when determining early intervention protocols for infants followed-up in NICU.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.