Peripheral Choroidal Vascular Development in Retinopathy of Prematurity using Ultra-Widefield Optical Coherence Tomography Angiography

Abstract

Purpose : While the choroid is critical for retinal perfusion and likely retinal development, it has been understudied in retinopathy of prematurity (ROP), in part due to difficulties in imaging the choroid outside of macular structural optical coherence tomography (OCT). In this retrospective case series, we employ an investigational ultra-widefield OCT angiography (UWF-OCTA) device with sufficiently fast scan times capable of performing choroidal angiography, to visualize choroidal growth patterns in neonates with ROP.

Methods : We utilized an 800Khz, 140° field of view UWF-OCTA device to image select infants diagnosed with ROP in the neonatal intensive care unit (NICU) of Oregon Health & Science University between September 2023 and December 2023. Each imaging session collected OCT and OCTA volumes in real-time used to create OCT and OCTA en face images of retinal and choroidal architecture, which were qualitatively assessed with respect to topographic spread compared to noted ROP disease.

Results : Among the 10 NICU infants who were included, the distribution of ROP severity was stage 1 (n=2), stage 2 (n=6), stage 3 (n=2). The mean birth weight was 705.1 ± 163.8g and the mean gestational age was 24 weeks, 6 days ± 7.1 days. Choroidal vessel growth was arrested at the retinal vascular-avascular junction for all stage 2 and 3 cases (80%) (Figure 1). The choroidal vessels in stage 1 cases (20%) progressed peripheral to the retinal avascular junction.

Conclusions : UFW-OCTA demonstrates choroidal vessel development appears to be arrested in stage 2 and 3 ROP, matching that of the overlying retinal vessels. Understanding choroidal vascular growth in ROP patients may present a new biomarker for ROP severity, and suggests new pathophysiologic mechanisms.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.

 

Figure 1. (A) En face OCT image captured using an investigational ultrahigh-speed handheld swept-source OCT angiography imaging system on a NICU patient with stage 3 ROP. (B) Corresponding OCT angiography en face image of the inner retina in the same infant, highlighting the vascularized retina. Blue arrows in both (A) and (B) indicate the region of extraretinal neovascular proliferation. (C) OCT angiography en face image showcasing the choroidal vasculature in the same infant.