Hematocrit significantly confounds diffuse correlation spectroscopy measurements of blood flow

• Type of Material: Article
• Authors: Eashani Sathialingam, Georgia Institute of Technology; Evelyn Kendall Williams, Georgia Institute of Technology; Seung Lee, Emory University; Courtney E. McCracken, Emory University; Wilbur Lam, Emory University; Erin Buckley, Emory University
• Language: English
• Date: 2020-08-01
• Publisher: Optical Society of America
• Publication Version: Final Published Version
• Copyright Statement: © 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.
• License: Creative Commons Attribution-NonCommercial 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1364/BOE.397613
• Title of Journal or Parent Work: Biomedical Optics Express
• Volume: 11
• Issue: 8
• Start Page: 4786
• End Page: 4799
• Grant/Funding Information: National Institutes of Health10.13039/100000002 (R21-HL138062); American Heart Association10.13039/100000968 (19POST34380337).
• Keywords: Self-diffusion; Life Sciences & Biomedicine; Children; Cerebral oxygen metabolism; Science & Technology; Radiology, Nuclear Medicine & Medical Imaging; Cell; Hemodynamics; Optics; Dispersion; Scattering; Concentrated disadvantage; Particles; Biochemical Research Methods; Biochemistry & Molecular Biology; Physical Sciences
• Research Categories: Physics, Optics; Health Sciences, Opthamology; Chemistry, Biochemistry; Biology, Cell

Abstract

Diffuse correlation spectroscopy (DCS) is an optical modality used to measure an index of blood flow in biological tissue. This blood flow index depends on both the red blood cell flow rate and density (i.e., hematocrit), although the functional form of hematocrit dependence is not well delineated. Herein, we develop and validate a novel tissue-simulating phantom containing hundreds of microchannels to investigate the influence of hematocrit on blood flow index. For a fixed flow rate, we demonstrate a significant inverse relationship between hematocrit and blood flow index that must be accounted for to accurately estimate blood flow under anemic conditions.