Repeatability and Reproducibility of Vascular Density Quantification on CIRRUS HD-OCT with AngioPlex

Abstract

Purpose : To determine the repeatability and reproducibility of vascular density measurements using CIRRUS™ HD-OCT 5000 with AngioPlex™ OCT Angiography (ZEISS, Dublin, CA) on normal and diseased eyes.

Methods : Subjects were divided into 2 groups in this prospective study. Group 1 (n=12) consisted of healthy subjects with no systemic or ocular disease; group 2 (n=15) consisted of subjects with a variety of retinal diseases, including diabetic retinopathy, age-related macular degeneration, and glaucoma. Subjects were scanned on 3 commercial CIRRUS HD-OCT devices with AngioPlex capability. Each study eye was randomized to be scanned with either the Angiography 3x3 mm or 6x6 mm scan pattern, and 3 scans were acquired centered on the fovea, giving a total of 9 scans per eye. The order in which the subjects were scanned with an operator-device combination was randomized. The preset superficial en face layer was then analyzed with investigational software to determine vascular density. Two measures were used: the area of blood vessels, and the length of blood vessels. The software quantified density measurements in each subfield of the ETDRS grid, as well as average densities for each ring of the ETDRS grid. Analysis of variance was used to calculate the repeatability and reproducibility standard deviations for each subfield. Coefficient of variation (CV) was calculated by dividing these by the mean measurement.

Results : Repeatability and reproducibility of vascular density measurements are shown in Table 1 and 2.

Conclusions : Repeatability and reproducibility of vascular density measurements are generally good. The small difference between reproducibility and repeatability suggests that the effect of instrument and operator are negligible. Retinal vasculature is known to be affected in the setting of diseases such as diabetes mellitus and glaucoma.^{1, 2} Several studies have shown that retinal vascular density decreases with progression of disease.³ Given the repeatability and reproducibility of these measurements, retinal vascular density may aid in the monitoring of disease progression or treatment response.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.

 

Table 1. Repeatability and reproducibility of vascular density measurements on healthy eyes.

 

Table 2. Repeatability and reproducibility of vascular density measurements on diseased eyes.