Absolute blood velocity measured with a modified fundus camera.
We present a new method for the quantitative estimation of blood flow velocity, based on the use of the Radon transform. The specific application is for measurement of blood flow velocity in the retina. Our modified fundus camera uses illumination from a green LED and captures imagery with a high-speed CCD camera. The basic theory is presented, and typical results are shown for an in vitro flow model using blood in a capillary tube. Subsequently, representative results are shown for representative fundus imagery. This approach provides absolute velocity and flow direction along the vessel centerline or any lateral displacement therefrom. We also provide an error analysis allowing estimation of confidence intervals for the estimated velocity.
Portland State University, Department of Electrical and Computer Engineering, 1900 Southwest Fourth Avenue, Portland, Oregon 97201, USA. donald.duncan@pdx.edu
Donald D
DD
Duncan
Paul
P
Lemaillet
Mohamed
M
Ibrahim
Quan Dong
QD
Nguyen
Matthias
M
Hiller
Jessica
J
Ramella-Roman
D001783:Blood Flow Velocity; D016001:Confidence Intervals; D003941:Diagnostic Techniques, Ophthalmological / Q000295:instrumentation* / Q000706:statistics & numerical data; D018056:Hemorheology; D006801:Humans; D066298:In Vitro Techniques; D017078:Laser-Doppler Flowmetry; D009887:Ophthalmoscopy; D055620:Optical Phenomena; D019047:Phantoms, Imaging; D012171:Retinal Vessels / Q000502:physiology*; D041623:Tomography, Optical Coherence