title: Bidirectional Doppler Fourier-domain optical coherence tomography for measurement of absolute flow velocities in human retinal vessels.
abstract: We describe a bidirectional color Doppler Fourier-domain optical coherence tomography system capable of measuring absolute velocities of moving scatterers by illuminating the sample with two linearly and orthogonally polarized beams, incident at a known angle on the sample. The velocity calculation is independent of the exact orientation of the velocity vector in the detection plane. First measurements were performed on a rotating disk driven at well-defined velocities and tilted by various small angles. Our results indicate a high correlation between preset and calculated velocities (correlation coefficient 0.999) and the independency of these velocities from the tilting angle of the disk. We demonstrate that bidirectional color Doppler optical coherence tomography allows for the measurement of absolute blood flow values in vivo in human retinal vessels.
authors.affiliation: Center for Biomedical Engineering and Physics, Medical University of Vienna, Vienna, Austria.
authors.forename: René M
authors.initials: RM
authors.lastname: Werkmeister
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Dragostinoff
authors.forename: Michael
authors.initials: M
authors.lastname: Pircher
authors.forename: Erich
authors.initials: E
authors.lastname: Götzinger
authors.forename: Christoph K
authors.initials: CK
authors.lastname: Hitzenberger
authors.forename: Rainer A
authors.initials: RA
authors.lastname: Leitgeb
authors.forename: Leopold
authors.initials: L
authors.lastname: Schmetterer
mesh_terms: D001783:Blood Flow Velocity; D004867:Equipment Design; D005583:Fourier Analysis; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D017078:Laser-Doppler Flowmetry / Q000379:methods*; D015233:Models, Statistical; D055095:Optics and Photonics; D012160:Retina / Q000033:anatomy & histology / Q000473:pathology*; D012171:Retinal Vessels / Q000473:pathology*; D012542:Scattering, Radiation; D041623:Tomography, Optical Coherence / Q000379:methods*