Abstract
Purpose:
Experiments were performed to evaluate the validity of absolute flow velocity measurements with a dual-beam bidirectional Doppler Fourier-domain optical coherence tomography (FD-OCT) system.
Methods:
In vitro and in vivo experiments were done. The flow velocities of diluted milk through a glass capillary were measured at 30 different preset velocities In vivo the validity of the method for measuring blood flow in retinal vessels was tested at bifurcations and the continuity equation was verified. In addition, the effect of 100% oxygen breathing was assessed and the data obtained from retinal arteries and veins were compared. Measurements of retinal diameters, using the Dynamic Vessel Analyzer.
Results:
Flow velocities as measured with bidirectional Doppler FD-OCT in the glass capillary were in good agreement with the preset velocities (r = 0.994, P < 0.001 each). No significant difference was found between flow in the trunk vessels before the bifurcation (11.3 +/- 5.2 micorL/min) and the sum of flows in the daughter vessels (10.7 +/- 4.8 micorL/min). 100% oxygen breathing caused a pronounced decrease in retinal blood flow (-52%, p < 0.001). Good agreement was found between measurement of retinal blood flow as assessed from arteries and veins.
Conclusions:
Dual-beam bidirectional Doppler FD-OCT is an accurate method for measuring retinal blood velocity and, thus, offers high potential for examination of retinal blood flow in ocular disease.
Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
436 blood supply •
688 retina