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Doppler Optical Coherence Tomography of Retinal Circulation
Published on: September 18, 2012
High-velocity-flow imaging with real-time Doppler optical coherence tomography
Richard Villey1, Lionel Carrion, Dominic Morneau
1Centre d'optique, photonique et laser, Department of Engineering Physics, Ecole Polytechnique de Montréal, P.O. Box 6079, Station Centre-ville, Montreal, Quebec, Canada.
Applied Optics
|June 3, 2010
Summary
We developed a real-time Doppler optical coherence tomography (OCT) system using the zero-crossing method for accurate fluid velocity measurements up to 10 m/s. This system provides reliable, artifact-free velocity maps for laminar and turbulent flows, even with steep gradients.
Area of Science:
- Biomedical Engineering
- Optical Physics
- Fluid Dynamics
Background:
- Optical Coherence Tomography (OCT) is a valuable imaging technique.
- Measuring fluid velocity with OCT often faces challenges like phase aliasing and artifacts.
- Existing methods may struggle with complex flow patterns and steep velocity gradients.
Purpose of the Study:
- To present a novel real-time time-domain Doppler OCT system.
- To enable accurate velocity measurements in fluid flows using the zero-crossing method.
- To overcome limitations of existing OCT velocimetry techniques.
Main Methods:
- Development of a real-time time-domain Doppler OCT system.
- Implementation of the zero-crossing method for velocity estimation.
- Acquisition and real-time processing of 1D and 2D velocity profiles.
Main Results:
- The system achieved a line rate of approximately 500 Hz with real-time image processing.
- Accurate velocity measurements were obtained for fluid flows ranging from 1 cm/s to over 3 m/s.
- The system successfully mapped velocity profiles in both laminar and turbulent flows, including those with steep gradients.
Conclusions:
- The developed zero-crossing based Doppler OCT system offers reliable, artifact-free fluid velocity measurements.
- The system is highly suitable for investigating complex velocity profiles and steep gradients in real time.
- This technology advances the capability for precise fluid dynamics analysis in various scientific and engineering fields.
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