A Quantitative Normative Database for Widefield Swept-Source OCT Angiography in the Pediatric Population

Abstract

Purpose : Normative data are currently lacking for widefield swept-source optical coherence tomography angiography (WF SS-OCTA) (PLEX® Elite 9000; Carl Zeiss Meditec, Dublin, CA) in the pediatric population as a baseline to compare for pathologic findings. Therefore, we aim to report quantitative vascular metrics of healthy control eyes of children.

Methods : This is a cross-sectional observational study of healthy eyes of children (age 6-18) without ocular comorbidities who were imaged on the PLEX® Elite 9000 instrument at 100-kHz scanning rate using 3×3, 6×6, and 12×12-mm protocols centered on the fovea between July 2019 and September 2023. Scans were uploaded to the ARI Network (Zeiss Portal v5.4) and processed with the macular density algorithm (v.0.7.3.3) to calculate vessel density (VD) and vessel skeletonized density (VSD) in the superficial capillary plexus (SCP), deep capillary plexus, and whole retina (WR), as well as foveal avascular zone (FAZ) metrics. Mixed-effects multiple linear regression models and the Mann-Whitney U test were used for statistical analyses.

Results : A total of 48 eyes of 39 children (72% male) were included. Median age was 14 years (interquartile range 10-16). Male sex was associated with lower VD and VSD compared to female sex (P < 0.05). Greater age was associated with higher VD and VSD in the 6×6-mm scans (P < 0.05). FAZ circularity decreased with age (P=0.017). Children above 14 years demonstrated higher VSD of both the SCP and WR in the inner ETDRS rings of the 6x6-mm scans, and in the outer ETDRS rings of the 12x12-mm scans (P < 0.05). Additionally, they showed an increased VD of the same slabs in the outer rings of both the 6x6 and 12x12-mm scans compared to younger participants (P < 0.05). Children of White race and not of Hispanic ethnicity had a lower VD and VSD of the SCP in the inner superior ring of the 3x3-mm scans, a higher VD and VSD of the SCP and WR in the central ring of the 6x6-mm scans, and a lower FAZ area in the 6×6-mm scans (P<0.05).

Conclusions : This study presents a normative database for widefield vascular metrics in pediatric subjects across various angiogram sizes. Our findings demonstrate that, when referencing these values, researchers should account for variables such as sex, age, race, and ethnicity. This database offers a valuable reference for comparing SS-OCTA measurements in pathological contexts.

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