Measurement of total blood flow in the normal human retina using Doppler Fourier-domain optical coherence tomography.
OBJECTIVE
To measure total retinal blood flow in normal human eyes using Doppler Fourier-domain optical coherence tomography (FD-OCT).


METHODS
10 normal people aged 35 to 69 years were measured for the right eye using Doppler FD-OCT. Double circular scans around the optic nerve heads were used. Four pairs of circular scans that transected all retinal branch vessels were completed in 2 s. Total retinal blood flow was obtained by summing the flows in the branch veins. Measurements from the eight scans were averaged. Veins with diameters >33 microm were taken into account.


RESULTS
Total retinal blood flow could be measured in eight of 10 subjects: mean (SD) = 45.6 (3.8) microl/min (range 40.8 to 52.9 microl/min). The coefficient of variation for repeated measurements was 10.5%. Measured vein diameters ranged from 33.3 to 155.4 mum. The averaged flow speed was 19.3 (2.9) mm/s, which did not correlate with vessel diameter. There was no significant difference between flows in the superior and inferior retinal hemispheres.


CONCLUSIONS
Double circular scanning using Doppler FD-OCT is a rapid and reproducible method to measure total retinal blood flow. These flow values are within the range previously established by laser Doppler flowmetry.
Wang
Y
Y
Center for Ophthalmic Optics & Lasers, Doheny Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA. yiminwan@usc.edu
Lu
A
A
Gil-Flamer
J
J
Tan
O
O
Izatt
J A
JA
Huang
D
D
D000328:Adult; D000368:Aged; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow / Q000502:physiology; D015203:Reproducibility of Results; D012169:Retinal Vein / Q000033:anatomy & histology / Q000502:physiology; D012171:Retinal Vessels / Q000502:physiology*; D041623:Tomography, Optical Coherence / Q000379:methods