Visual function and optical coherence tomography angiography features in children born preterm

Abstract

Purpose : Preterm children have an increased risk of impaired vision from retinopathy, strabismus, and high refractive error. Optical coherence tomography studies have confirmed abnormal foveal development in preterm children, and aim of this study was to investigate the relationship between foveal parameters and visual function in preterm children.

Methods : Eighty eyes (40 eyes of former preterm infants and 40 age-matched full-term control eyes) were analyzed. Subjects underwent complete eye examinations including best corrected visual acuity (BCVA), stereovision tests, and imaging with the Optovue XR Avanti optical coherence tomography angiography (OCT-A). Foveal morphological parameters including foveal depth (FD), central foveal thickness (CFT), inner retinal area (IRA) and outer retinal area (ORA) were measured on a central horizontal B-scan (Figure 1). Foveal vasculature parameters including foveal avascular zone (FAZ) area, superficial capillary plexus vessel density (SCP-VD) and deep capillary plexus vessel density (DCP-VD) were measured on OCT-A.

Results : LogMAR BCVA was significantly increased in preterm children compared to controls (0.17 ± 0.17 vs. - 0.02 ± 0.05, p < 0.0001) with insignificant (p = 1) stereovision tests. CFT (251.20 ± 40.63 vs. 186.63 ± 20.46 µm, p < 0.0001), IRA (0.13 ± 0.03 vs. 0.09 ± 0.01 mm², p < 0.0001), and ORA (0.29 ± 0.04 vs. 0.26 ± 0.04 mm², p = 0.03) were significantly increased in preterm compared to control eyes. FD (69.80 ± 32.15 vs. 106.03 ± 17.58 µm, p < 0.0001) and FAZ (0.08 ± 0.10 vs. 0.24 ± 0.10 mm², p < 0.0001) were significantly decreased in preterm compared to control eyes. The SCP-VD (41.49 ± 5.06 vs. 33.90 ± 5.74 %, p < 0.0001) and DCP-VD (38.75 ± 6.21 vs. 31.14 ± 6.51 %, p < 0.0001) at the fovea (1 mm) were significantly increased in preterm compared to control eyes. LogMAR BCVA was negatively correlated to FD (r = - 0.42, p = 0.001) and FAZ (r = - 0.53, p < 0.001), and positively correlated to CFT (r = 0.32, p = 0.01) and IRA (r = 0.32, p = 0.01) indicating worse visual acuity was associated with a smaller FAZ, shallower FD, thicker CFT, and larger IRA.

Conclusions : Foveal morphology and vasculature changes in preterm children were associated with impaired visual function. Further longitudinal studies are required to study changes in these parameters over time.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.

 

Quantification of foveal morphology

 

Quantitative analyses of (A) FAZ, (B) SCP-VD and (C) DCP-VD