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Quantitative blood flow velocity imaging using laser speckle flowmetry.

ABSTRACT: Laser speckle flowmetry suffers from a debated quantification of the inverse relation between decorrelation time (?c) and blood flow velocity (V), i.e. 1/?c?=??V. Using a modified microcirculation imager (integrated sidestream dark field - laser speckle contrast imaging [SDF-LSCI]), we experimentally investigate on the influence of the optical properties of scatterers on ? in vitro and in vivo. We found a good agreement to theoretical predictions within certain limits for scatterer size and multiple scattering. We present a practical model-based scaling factor to correct for multiple scattering in microcirculatory vessels. Our results show that SDF-LSCI offers a quantitative measure of flow velocity in addition to vessel morphology, enabling the quantification of the clinically relevant blood flow, velocity and tissue perfusion.

SUBMITTER: Nadort A

PROVIDER: S-EPMC4850477 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Quantitative blood flow velocity imaging using laser speckle flowmetry.

Nadort Annemarie A Kalkman Koen K van Leeuwen Ton G TG Faber Dirk J DJ

Scientific reports 20160429

Laser speckle flowmetry suffers from a debated quantification of the inverse relation between decorrelation time (τc) and blood flow velocity (V), i.e. 1/τc = αV. Using a modified microcirculation imager (integrated sidestream dark field - laser speckle contrast imaging [SDF-LSCI]), we experimentally investigate on the influence of the optical properties of scatterers on α in vitro and in vivo. We found a good agreement to theoretical predictions within certain limits for scatterer size and mult ...[more]

PMID: 27126250

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