Macular OCT Characteristics at 36 Weeks' Postmenstrual Age in Infants Examined for Retinopathy of Prematurity

Purpose: To report our ability to capture,-grade reliably, and analyze bedside macular OCT images from preterm infants and relate OCT findings to biological factors and retinopathy of prematurity (ROP) status at a single time window in the Study of Eye Imaging in Preterm Infants (BabySTEPS). Design: Prospective, observational study. Participants: Preterm infants eligible for ROP screening with parental consent for research and a 36 +/- 1 weeks' postmenstrual age (PMA) visit. Methods: We imaged both eyes of preterm infants with an investigational noncontact, handheld swept-source (SS) OCT at the time of clinical ROP examinations. Macular OCT features and layer thicknesses for untreated eyes of infants at 36 +/- 1 weeks' PMA were compared with demographic data and clinical ROP examination performed by experts. Statistical analyses accounted for the use of both eyes of infants. Main Outcome Measures: Macular OCT features and layer thicknesses, gender, race or ethnicity, gestational age, birth weight, ROP stage, and plus disease. Results: We captured macular OCT from 169 eyes (1 eye excluded because of prior ROP treatment) at 36 +/- 1 weeks' PMA. The quality of OCT volumes was excellent in 33 eyes (19%), acceptable in 112 eyes (67%), poor in 24 eyes ( 14%), and unusable in 0 eyes (0%). Macular edema was present in 60% of eyes and was bilateral in 82% of infants with edema. At the fovea, retinal and inner nuclear layer thickness increased with edema severity: 183 +/- 36 mu m and 51 +/- 27 mu m in mild (16% of eyes), 308 +/- 57 mu m and 163 +/- 53 mu m in moderate (25%), and 460 +/- 76 mu m and 280 +/- 83 mu m in severe edema (12%), respectively. With an increase in ROP stage from 0 to 2, the mean +/- standard deviation retinal thickness at the fovea increased from 227 +/- 124 mu m to 297 +/- 99 mu m (P < 0.001). The choroid was thinner, 155 +/- 72 mu m, with preplus or plus disease versus without, 236 +/- 79 mu m (P = 0.04), whereas retinal thickness did not vary. Conclusions: We demonstrated the reliability of methods and the prevalence of OCT findings in preterm infants enrolled in BabySTEPS at a single time point of 36 +/- 1 weeks' PMA. Variations in layer thicknesses in infants at this time point may reflect abnormalities resulting from delay in foveal development that may be impacted by macular edema, ROP, or both. (C) 2020 by the American Academy of Ophthalmology

Automated summary

The study reported the reliability of capturing, grading, and analyzing bedside macular OCT images from preterm infants at 36 +/- 1 weeks' postmenstrual age, and the OCT findings were related to biological factors and retinopathy of prematurity status. Macular edema was present in 60% of eyes, and thicker inner nuclear layer was associated with more severe edema. Variations in layer thicknesses at 36 +/- 1 weeks' PMA in preterm infants may reflect abnormalities resulting from delay in foveal development impacted by macular edema, ROP, or both.