Early Postnatal Oxygen Exposure Predicts Choroidal Thinning in Neonates

Abstract

To evaluate whether choroidal thickness (CT) using arm-mounted optical coherence tomography (OCT) in infants screened for retinopathy of prematurity (ROP) correlates with oxygen exposure in neonates. METHODS.OCT images were obtained in infants screened for ROP in a single level IV neonatal intensive care unit. CT was measured at three different locations: the subfoveal center and 1.5 mm from the fovea center in each direction. Correlation and regression analyses were performed to determine the relationship between clinical factors and CT. Clinical factors included gestational age, birth weight, presence of bronchopulmonary dysplasia (BPD), and fraction of inspired oxygen (FiO 2 ) at defined time points: 30 weeks postmenstrual age (PMA), 36 weeks PMA, and on day of imaging. RESULTS.Mean subfoveal, nasal, and temporal choroidal thicknesses CT (SFCT, NCT, and TCT, respectively) were 228.0 ± 51.4 μm, 179.7 ± 50.3 μm, and 186.4 ± 43.8 μm, respectively. SFCT was found to be significantly thicker than NCT and TCT (P < 0.0001 and P = 0.0002, respectively), but no significant difference was found between NCT and TCT (P = 0.547). Compared with infants without BPD, infants with BPD had thinner SFCT and NCT (P = 0.01 and P = 0.0008, respectively). Birth weight was positively correlated with SFCT (r = 0.39, P = 0.01) and NCT (r = 0.33, P = 0.045) but not TCT. Gestational age and ROP stage were not significantly associated with CT. SFCT was found to be significantly thinner with higher average FiO 2 supplementation levels at 30 weeks PMA (r = -0.51, P = 0.01) but not at 36 weeks PMA. Regression analysis revealed that FiO 2 at 30 weeks PMA was an independent predictor of SFCT in infants screened for ROP (P = 0.01). CONCLUSIONS.Early postnatal exposure (<32 weeks PMA) to higher oxygen supplementation in premature neonates statistically predicts choroidal thinning.

Characterization of Foveal Development in Treatment-Naïve Extremely Preterm Infants

“…The Spectralis Flex Module (Heidelberg Engineering GmbH, Heidelberg, Germany) was used to obtain the OCT images, using an acquisition protocol consisting of seven horizontal B-scans spaced 60 to 120 microns apart through the central macula, with the foveal center defined as the shallowest point. 19 …”

Choroidal measurements in decision making for retinopathy of prematurity: a decision tree analysis

“…In consensus with previous studies [ 23 ], we also demonstrated the choroid was thinner in ROP neonates with the plus disease compared to not-plus disease. It has been suggested that the thinning of the choroid in ROP neonates may be due to oxidative stress and choroidal vascular loss [ 7 , 12 , 24 , 25 ]. This choroidal vascular loss has been proven angiographically.…”

Preterm infant retinal OCT markers of perinatal health and retinopathy of prematurity

“…They included gestational age, birth weight, PMA at imaging and the fraction of inspired oxygen (FiO 2 ) at 30 weeks, 36 weeks and the day of OCT imaging in their analysis, where higher FiO 2 at 30 weeks was independently associated with choroidal thinning implying that choroidal thickness was mainly impacted by early postnatal oxygen supplementation ( 67 ). Similar to our hypothesis, He et al also concluded that hyperoxia-induced vascular attenuation may be responsible for the choroidal thinning ( 66 , 67 ).…”

“…Several studies have found a correlation between ROP and choroidal thinning ( 8 , 15 , 16 , 67 ). In Moreno et al, we reported thinner choroid in eyes of preterm infants and in those infants with ROP ( 8 ).…”

“…While the exact mechanism underlying the complex relationship between oxygen supplementation, choroidal thinning and ROP is still unknown, it is pertinent to recognize that these published studies demonstrate associations and not causality ( 66 , 67 ). Future directions include additional studies and assessment of the long-term implication of oxygen supplementation and poor postnatal growth related choroidal thinning on visual function and neurodevelopmental outcomes in preterm infants.…”