Shear‐induced diffusion of red blood cells measured with dynamic light scattering‐optical coherence tomography

Abstract

Quantitative measurements of intravascular microscopic dynamics, such as absolute blood flow velocity, shear stress and the diffusion coefficient of red blood cells (RBCs), are fundamental in understanding the blood flow behavior within the microcirculation, and for understanding why diffuse correlation spectroscopy (DCS) measurements of blood flow are dominantly sensitive to the diffusive motion of RBCs. Dynamic light scattering‐optical coherence tomography (DLS‐OCT) takes the advantages of using DLS to measure particle flow and diffusion within an OCT resolution‐constrained three‐dimensional volume, enabling the simultaneous measurements of absolute RBC velocity and diffusion coefficient with high spatial resolution. In this work, we applied DLS‐OCT to measure both RBC velocity and the shear‐induced diffusion coefficient within penetrating venules of the somatosensory cortex of anesthetized mice. Blood flow laminar profile measurements indicate a blunted laminar flow profile and the degree of blunting decreases with increasing vessel diameter. The measured shear‐induced diffusion coefficient was proportional to the flow shear rate with a magnitude of ~0.1 to 0.5 × 10−6 mm2. These results provide important experimental support for the recent theoretical explanation for why DCS is dominantly sensitive to RBC diffusive motion.

Document Details

Document Type
Pub Defense Publication
Publication Date
Aug 09, 2017
Source ID
10.1002/jbio.201700070

Entities

People

  • Baoqiang Li
  • Buyin Fu
  • David A. Boas
  • Jianbo Tang
  • Jonghwan Lee
  • Sava Sakadzic
  • Sefik Evren Erdener
  • Stefan A Carp

Organizations

  • Air Force Office of Scientific Research
  • Brown University
  • Harvard Medical School
  • National Institutes of Health

Tags

Fields of Study

  • Physics

Readers

  • Cardiovascular Physiology
  • Fluid Mechanics and Fluid Dynamics.
  • Medical Imaging.