Abstract
Purpose:
To investigate long-term functional and morphological alterations of the fovea in a cohort of former preterm infants screened systematically for retinopathy of prematurity (ROP) with serial wide-field digital imaging (RetCam I).
Methods:
140 children (age 6-12 y, mean 9.3y) took part in the long-term study: former premature infants without ROP (A: n=60); with spontaneously resolved ROP (B: n=40); with treated ROP (C: n=10); and an age-matched control group of children born at term (N: n=30). Examinations included visual acuity (VA) testing with Landolt-C, orthoptic status, fundus-controlled perimetry (FCP) and fixation stability (FS) (both on an MP1), SD-OCT-imaging (Spectralis), Ganzfeld ERG (Espion E3) and mfERG (Veris), retinal imaging (FF450plus) and ultra-widefield-imaging (Optos 200Tx). Foveal light increment sensitivity (LIS) was tested employing a 4-2 staircase strategy with 200ms stimulus duration and stimulus size Goldmann I. OCT single and volume scans were segmented and analyzed with custom made software (DiOCTA). Retinal morphology was compared with RetCam images at the time of ROP screening.
Results:
Mean VA, central LIS and FS decreased with increasing severity of ROP in medical history. In contrast, central full retinal thickness increased with increasing severity from 240µm (A) to 275µm (C), and was thinnest in the control group (N: 221µm). The thickness of the outer nuclear layer increased from 125µm (N) to 145µm (C) and the thickness of the outer segments decreased from 29µm (N) to 24µm (C). With increasing severity of ROP, the depth of the foveal pit decreased and increasingly thicker inner retinal layers were superimposed to the outer nuclear layer in the center (C: 83µm) compared to the control group (N: 7µm). The incidence of a shallow or absent foveal pit increased with severity of ROP from 25% in A, 45% in B and 75% in C. A shallow pit was also seen in 5% in N. The morphology of the fovea could be identified in early screening imaging, matched to current images and reflected the configuration of the foveal pit in current OCT-images.
Conclusions:
The foveae of primary school children with a history of mild or severe ROP display distinct structural changes associated with reduced retinal function. Careful analysis of early screening images allows predicting the subsequent development of the fovea in preterm born children.
Keywords: 698 retinal development •
550 imaging/image analysis: clinical •
706 retinopathy of prematurity