Purpose
To prospectively report foveal morphology on spectral domain optical coherence tomography (SD-OCT) in premature infants with and without retinopathy of prematurity (ROP) in their first corrected year of life and to correlate this with visual acuity
Methods
Fifty eyes (25 premature infants) who completed photo documented ROP screening were subjected to hand-held SD-OCT (Bioptigen,NC,USA) imaging in the office along with visual acuity assessment using Teller Acuity Cards at 3,6,9 and 12 months of corrected ages respectively. Best rectangular scans representing the foveal center were selected by masked pediatric retinal specialists. Images were evaluated for individual layers of the retina, inner retinal layer fusion or immaturity, foveal dip and foveal tent.Factorial ANOVA and univariate analysis of variance tests were performed.
Results
The overall mean visual acuity improved with increasing study intervals (1.75, 1.50, 1.28 and 1.17 logMar at 3,6,9, and 12 months respectively (P < 0.0001).Morphological features on SD-OCT that positively correlated with visual acuity included:1) inner retinal layer fusion (41.3%, 54.2%, 70%, 72%, P=0.006) and presence of 2)outer segment-retinal pigment epithelium (OS-RPE)(4.3%, 47.9%, 72.0%, 76.0%, P < 0.0001) 3)external limiting membrane(10.9%, 52.1%, 74.%, 84%, P < 0.0001) 4)foveal tent (8.7%, 52.1%, 76%, 86%, P < 0.0001) assessed at 3,6,9,and 12 months respectively.Subgroup analysis correlating SD-OCT layers with the presence (n=32) and absence (n=18) of ROP showed that in the group without ROP there was a significant difference between those with and without these layers,with the former showing better acuity through the study period.However, in the group that had ROP, there was no significant different between those with and without these layers (Fig. 1 and 2)
Conclusions
This is the first prospective study correlating visual acuity with SD-OCT morphology in premature infants in the first year of life.Visual acuity improves as the infant grows from 3 to 12 months.Four morphological features on SD-OCT correlated with better vision in the group without ROP.In the ROP cohort, although vision improved with age, SD-OCT features seemed to play a less influential role in this process