Abstract
PurposeTo evaluate the topographic distribution of the choriocapillaris (CC) flow deficits in a population of healthy subjects.MethodsUsing a swept-source optical-coherence tomography angiography (SS-OCTA) device, two repeated volume 6 x 6 mm and 3 x 3 mm scans were acquired in healthy subjects at the Doheny—UCLA Eye Centers. The en-face CC angiogram was binarized and analyzed for percentage of flow deficits (FD%) using a grid of progressive, concentric rings covering a circular area with a diameter of 2.5 mm (in the 3 x 3 mm scans) and 5 mm (in the 6 x 6 mm scans). The FD% for each ring was plotted against the distance from the fovea. The linear trendline of the resulting curve was analyzed and the slope (m) and intercept (q) were computed.ResultsSeventy-five eyes of 75 subjects were enrolled and divided into three subgroups based on age (year ranges: 21–40, 41–60 and 61–80). For the entire cohort and within each subgroup, there was a significant association between distance from the fovea and FD% in both 3X3 mm and 6X6 mm scans, with flow deficits increasing with closer proximity to the foveal center. Age was a significant predictor for both m and q for both scan patterns, with older subjects showing a steeper slope.ConclusionsIn SS-OCTA images, the topographic distribution of CC flow deficits varies with distance from the fovea and age. In particular, the FD% tends to decrease from the fovea towards the periphery, with a steeper decline with advancing age. These normal trends may need to be accounted for in future studies of the CC in disease.
Highlights
Using a swept-source optical-coherence tomography angiography (SS-optical coherence tomography angiography (OCTA)) device, two repeated volume 6 x 6 mm and 3 x 3 mm scans were acquired in healthy subjects at the Doheny—University of California–Los Angeles (UCLA) Eye Centers
For the entire cohort and within each subgroup, there was a significant association between distance from the fovea and FD% in both 3X3 mm and 6X6 mm scans, with flow deficits increasing with closer proximity to the foveal center
Sadda: Allergan (C,F), Carl Zeiss Meditec (F), Genentech (C, F), Iconic (C), In SS-OCTA images, the topographic distribution of CC flow deficits varies with distance from the fovea and age
Summary
The development of optical coherence tomography angiography (OCTA) has provided new insights into the retinal and choroidal microvasculature. allowing individual vascular plexi to be evaluated at extremely high resolution [1]. A post-processing analysis of these images allows the quantification of the black pixels (flow deficits) within the CC This type of analysis has been used in many studies as an indication of CC impairment in various retinal diseases [13]. It is reasonable to hypothesize that the CC could demonstrate significant regional variation (personal communication, Phil Rosenfeld) This hypothesis is supported by histologic studies which have demonstrated differences in the CC morphology in central compared to more peripheral regions [2]. These topographical variations in the CC may be significant confounders of studies which compare CC flow deficits within regions of interest in the macula [3,4,15,16]. To study the potential impact of these regional and age-related variations, we studied the topographical distribution of CC flow deficits in a cohort of normal subjects
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
