Measurement of retinal blood flow using a Doppler optical coherence tomography auto-flowmeter in humans

Abstract

Purpose : To report the reproducibility of retinal blood flow (RBF) measurements using a newly developed Doppler optical coherence tomography (OCT) auto-flowmeter in humans.

Methods : We measured the retinal arterial blood flow in four healthy volunteers without pupil dilation. The system is based on spectral-domain OCT with fully automated alignment and measurement functionality. Doppler angle was preset at 80 degrees before the measurement to achieve the stable measurement in the automated measurement, where appropriate Doppler angle was predicted and searched by the auto-alignment procedure. Five repeated measurements were performed using the integrated follow-up scheme of the OCT system. RBF was calculated by integrating the velocity within predicted vessel area. The reproducibility of the RBF measurements was assessed by calculating the coefficients of variation (CV) for repeated measurements (5 times) of the Doppler angle (A), mean retinal blood velocity (V), and RBF at the temporal retinal arterioles.

Results : Averaged Doppler angle for four subjects was within a range of 78-83 degrees. The CV for A, V, and RBF were 1.1±0.4%, 12.3±6.6%, and 14.5±11.2%, respectively. These results showed the good repeatability that was comparable to the previously-reported Doppler OCT system (Yoshida et al., IOVS 2013;54:ARVO E-abstract 4664). Since the system used in this study obtains the measurements automatically, it is unnecessary to consider inter-operator differences.

Conclusions : The current study showed that the Doppler OCT auto-flowmeter enables accurate and reproducible measurements of retinal arterial blood flow in humans.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.