Objective Assess outer retinal layer maturation during late gestation and early postnatal life using optical coherence tomography (OCT) and histology. Methods Thirty-nine subjects ranging from 32 weeks post-menstrual age (PMA) to 4 years were imaged using a hand held OCT (102 imaging sessions). Foveal images from 16 subjects (21 imaging sessions) were normal and evaluated for inner retinal excavation and presence of outer retinal reflective bands. Reflectivity profiles of central, parafoveal, and perifoveal retina were extracted and compared to age-matched histological sections. Results Foveal pit morphology in infants was generally distinguishable from adults. Reflectivity profiles showed a single hyper-reflective band at the fovea in all infants less than 42 weeks PMA. Multiple bands were distinguishable in the outer retina at the perifovea by 32 weeks PMA, and at the fovea by 3 months post term. By 17 months postnatal the characteristic appearance of four hyper-reflective bands was evident across the foveal region. These features are consistent with previous results from histology. A ‘temporal divot’ was present in some infants and foveal pit morphology and extent of inner retinal excavation was variable. Conclusions Hand-held OCT imaging is a viable technique for evaluating neonatal retinas. In premature infants, who do not develop ROP, the foveal region appears to follow a developmental time course similar to in utero maturation. Clinical Relevance As pediatric OCT imaging becomes more common, a better understanding of normal foveal and macular development is needed. Longitudinal imaging offers the opportunity to track postnatal foveal development in preterm infants where poor visual outcomes are anticipated or to track treatment outcomes in this population.

Objective To evaluate subclinical macular findings in premature patients at risk of retinopathy of prematurity (ROP) with the use of handheld spectral domain-optical coherence tomography (SD-OCT). Design Prospective, observational case series. Participants Forty-nine prematurely born neonates. Methods Forty-nine infants were imaged using a handheld SD-OCT. Images were acquired in non-sedated infants in the neonatal intensive care unit. Some patients were followed and re-imaged over the course of several weeks. Two hundred ninety-eight total images were acquired, and evaluated for cystoid macular edema (CME) and persistence of inner retinal layers. Main Outcome Measures In vivo determination of foveal retinal lamination, image analysis and clinical observation. Results Two hundred forty (81%) of the images from 45 patients were usable (defined as having scans passing through the fovea with clearly identifiable retinal layers). Persistence of one or more inner retinal layers was seen in 42 patients (93%). Patients with at least one persistent layer, 16, 5, 7, 13 and 1 had a maximum ROP stage of 0, 1, 2, 3, and 4A respectively. CME was seen in 25 of the 45 patients (56%) during one or more imaging sessions. CME was present in 9, 1, 5, 9, and 1 patient with maximum ROP stage of 0, 1, 2, 3, and 4A respectively. Conclusions Our data suggests there is persistence of inner retinal layers in premature infants, regardless of maximal ROP stage. Subclinical CME is seen in premature infants; however, CME does not appear to be correlated with ROP stage. This suggests that there maybe other etiologies for the CME seen in this patient population. Hand-held SD-OCT imaging is a viable technique for evaluating subclinical macular findings in premature infants, though larger datasets are needed from multiple centers to further evaluate the generalizability of these findings.