Early identification of cerebral visual impairments in infants born extremely preterm.

AIM Children born extremely preterm are at risk of visual processing problems related to brain damage. Damage in visual pathways can remain undetected by conventional magnetic resonance imaging (MRI) and functional consequences cannot always be predicted. The aim of this study was to assess the efficacy of processing visual information in infants born extremely preterm at a corrected age of 1 year using a communication-free visual function test based on eye tracking. METHOD Infants born extremely preterm (<29wks' gestation) without apparent white and grey matter damage on conventional MRI at 30 weeks' postmenstrual age were included (19 males, 1.01y [0.96-1.24] (median [25th-75th centiles]); 11 females, 0.99y [0.98-1.01]). At the corrected age of 1 year, reaction times to fixation (RTF) of specific visual properties displayed on an eye-tracker monitor were quantified and compared with results from a comparison group (eight males, 1.28y [1.01-1.33]; nine females, 1.10y [0.90-1.20]). RESULTS The infants in the preterm group had longer response times in detecting colour patterns (red-green) and motion compared with infants in the comparison group. No impairments were detected in oculomotor functions (saccades, pursuit, and fixations). INTERPRETATION The data suggest that delays in processing visual information can be identified in children born extremely preterm. The delays might be ascribed to deficits in neuronal connectivity in visual pathways at a microstructural level.