Abstract
Purpose :
Previous studies have shown changes in retinal microvasculature associated with macular dystrophies such as Stargardt disease (STGD). Optical coherence tomography angiography (OCT-A) can serve as a noninvasive modality to visualize and quantify such changes. We performed a prospective cross-sectional study to compare the macular vessel density (VD) in the choroid (CC), deep retina (DR), outer retina (OR) and superficial retina (SR) using OCT-A in normal individuals and in patients with clinical diagnosis of STGD.
Methods :
OCT-A images of the macula were acquired in 15 eyes of 8 normal individuals and in 25 eyes of 13 patients with STGD. En face images of the retinal vasculature were generated from the various layers. ImageJ software (NIH, Bethesda, MD) was used to assess the VD by calculating the ratio of pixels occupied by the vessels to the total number of pixels in each scan.
Results :
Controls (mean age, 25 years; males, 40%) had a mean VD of 45% in the CC, 36% in the DR, 20% in the OR and 28% in the SR. STGD patients (mean age, 44 years; males, 52%) had a mean VD of 42% in the CC, 27% in the DR, 20% in the OR and 26% in the SR. They had a statistically significantly lower mean VD in the DR than controls (p < 0.001).
Conclusions :
Patients with MD had a lower VD in the DR, suggesting that a measurable and statistically significant decrease in these vascular layers can occur after damage to the photoreceptors and retinal pigment epithelium. The variation in vascular density in different layers may be associated with progression and/or prognosis, which will require a prospective follow-up. OCT-A can be a useful non-invasive biomarker which may turn out useful to measure MD disease progression.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.