Optical coherence tomography for evaluating capillary waves in blood and plasma

Hsiao-Chuan Liu,Piotr Kijanka,Matthew W Urban

doi:10.1364/boe.382819

Abstract

Capillary waves are associated with fluid mechanical properties. Optical coherence tomography (OCT) has previously been used to determine the viscoelasticity of soft tissues or cornea. Here we report that OCT was able to evaluate phase velocities of capillary waves in fluids. The capillary waves of water, porcine whole blood and plasma on the interfacial surface, air-fluid in this case, are discussed in theory, and phase velocities of capillary waves were estimated by both our OCT experiments and theoretical calculations. Our experiments revealed highly comparable results with theoretical calculations. We concluded that OCT would be a promising tool to evaluate phase velocities of capillary waves in fluids. The methods described in this study could be applied to determine surface tensions and viscosities of fluids for differentiating hematological diseases in the future potential biological applications.

Highlights

Capillary waves are a surface wave propagating along the phase boundary of a fluid
In this article we propose that Optical coherence tomography (OCT) would be a promising tool to estimate phase velocities of capillary waves induced with acoustic radiation force in fluids
We focus on a single wavelength on the 3D-OCT images at 15 ms [Fig. 3(a)], the travel distance was 5.4 mm; the wave velocity is approximately 0.36 m/s

Summary

Introduction

Capillary waves are a surface wave propagating along the phase boundary of a fluid. Blood viscosity is mainly determined by the concentration of hematocrit [5]; the larger aggregation of red blood cells (RBCs), deformability of RBCs and plasma fibrinogen concentration contribute to an increase in blood viscosity [6]. Disorders of blood viscosity are significantly associated with the progression of coronary heart disease [7,8], peripheral artery diseases [9] stroke [10] and hyperviscosity syndromes [11,12] which occur in polycythaemia, leukemia, sickle cell diseases and paraproteinaemias [6]. According to Stokes theory [1], phase velocities of capillary waves are mainly associated with viscosities and surface tensions of fluids; evaluating phase velocities of capillary waves of fluids are essential

Methods

Results

Conclusion