Topographic Features in Retinopathy of Prematurity With en Face Ultra-Widefield OCT

Summary

ROP en face UWF-OCT – Describes 2 techniques to visualize vascular pathology and associated topographic changes.

Abstract

Purpose: This study presents 2 methods of en face visualization enabled by ultra-widefield (UWF) OCT, which provide topographic information of retinopathy of prematurity (ROP) without requiring direct visualization of cross-sectional scans.

Design: Evaluation of diagnostic technology.

Subjects: Infants undergoing ROP screening at Oregon Health Science University between June 2023 and October 2024, who consented to research imaging.

Methods: An investigational contact-based UWF-OCT captured 800 × 800 A-scans. Max intensity projections (MIP) were constructed, from the highest intensity pixel in each A-scan’s x-y coordinate plane. Retinal thickness maps (RTMs) were generated by first segmenting the retina with a previously trained U-net, then calculating the retinal thickness at each position in microns, and displaying it with a topographic colormap.

Main outcome measures: Cross-sectional and longitudinal qualitative evaluation of the diagnostic utility of MIP and RTM across the spectrum of ROP stage.

Results: MIP highlights areas of high signal attenuation, such as blood vessels and the atypical neurovascular thickening accompanying stage 1 or greater ROP. Retinal thickness maps reflect thickness information in the retina that highlights complementary aspects of the progression and spectrum of the stage. Retinal thickness maps also reveal subclinical elements of ROP morphology, such as the foveal contour, in some cases “stage 0” ROP, and cystoid macular edema.

Conclusions: This study presents 2 techniques to visualize pathology in ROP from UWF-OCT. Together, they enable both high-contrast visualization of the vascular features of ROP and the associated topographic changes across the spectrum of ROP.