Comparing en face swept-source optical coherence tomography images to RetCam photographs in the assessment of retinopathy of prematurity

Abstract

Purpose : In retinopathy of prematurity (ROP), color photographs are often used to document retinal findings or for telemedicine screening. This study aims to assess how processed SS-OCT images are affected by fundus pigmentation and may be used in evaluating Plus disease in premature infants when compared to color fundus images.

Methods : Premature infants with ROP had investigational handheld SS-OCT retinal imaging in the nursery and a record of fundus pigmentation (blonde, medium, or dark) under IRB-approved protocol. Several infants also had clinical RetCam imaging. SS-OCT images were auto-segmented and processed using custom software (DOCTRAP v63.9) to optimize en face retinal vessel visualization. Uncorrected OCT-based vascular images (OCTvi) were auto-montaged (i2K Retina; DualAlign LLC) and missed OCTvi were manually added to the montage. Multiple RetCam images per eye were adjusted in brightness/contrast to enhance vessel visibility. Three ROP experts rated OCTvi montages, then original and corrected RetCam images, for gradability and fundus pigmentation (Fig 1). Experts were then shown paired OCTvi and RetCam images for each eye and asked to note preference for evaluation of Plus disease.

Results : Viewing OCTvi montages from 6 visits of 5 eyes (3 blonde, 2 dark), 2 graders could not distinguish fundus pigmentation and the 3rd grader correctly classified pigmentation in 33% of eyes. In RetCam image assessment, graders identified fundus pigmentation in all eyes and were correct in 78% (14/18) of eyes. Contrast/brightness correction of RetCam images was considered useful in increasing vessel visibility in blonde and darkly pigmented eyes. OCTvi montages were preferred in 44% (8/18) of eyes due to reduced glare or clearer vessel visibility on a grayscale background. RetCam photographs were preferred in 56% (10/18) of eyes due to greater field of view or lack of artifacts. Of 72 assessed quadrants, experts reported that 63 OCTvi and 71 RetCam quadrants were visible. All graders expressed comfort using either imaging modality to evaluate Plus disease in all eyes.

Conclusions : OCTvi vasculature visibility appeared to be independent of fundus pigmentation. The findings from this sample encourage future studies to address the limitations of the OCTvi montages field of view and to explore the feasibility of using OCTvi montages as an alternative to color photographs.

This is a 2020 ARVO Annual Meeting abstract.