Dual shear wave induced laser speckle contrast signal and the improvement in shear wave speed measurement
Author(s)
Li, S
Cheng, Y
Eckersley, RJ
Elson, DS
Tang, M-X
Type
Journal Article
Abstract
Shear wave speed is quantitatively related to tissue viscoelasticity.
Previously we reported shear wave tracking at centimetre depths in
a turbid optical medium using laser speckle contrast detection. Shear wave
progression modulates displacement of optical scatterers and therefore modulates
photon phase and changes the laser speckle patterns. Time-resolved
charge-coupled device (CCD)-based speckle contrast analysis was used to
track shear waves and measure the time-of-flight of shear waves for speed
measurement. In this manuscript, we report a new observation of the laser
speckle contrast difference signal for dual shear waves. A modulation of
CCD speckle contrast difference was observed and simulation reproduces
the modulation pattern, suggesting its origin. Both experimental and
simulation results show that the dual shear wave approach generates an
improved definition of temporal features in the time-of-flight optical signal
and an improved signal to noise ratio with a standard deviation less than
50% that of individual shear waves. Results also show that dual shear waves
can correct the bias of shear wave speed measurement caused by shear wave
reflections from elastic boundaries.
Previously we reported shear wave tracking at centimetre depths in
a turbid optical medium using laser speckle contrast detection. Shear wave
progression modulates displacement of optical scatterers and therefore modulates
photon phase and changes the laser speckle patterns. Time-resolved
charge-coupled device (CCD)-based speckle contrast analysis was used to
track shear waves and measure the time-of-flight of shear waves for speed
measurement. In this manuscript, we report a new observation of the laser
speckle contrast difference signal for dual shear waves. A modulation of
CCD speckle contrast difference was observed and simulation reproduces
the modulation pattern, suggesting its origin. Both experimental and
simulation results show that the dual shear wave approach generates an
improved definition of temporal features in the time-of-flight optical signal
and an improved signal to noise ratio with a standard deviation less than
50% that of individual shear waves. Results also show that dual shear waves
can correct the bias of shear wave speed measurement caused by shear wave
reflections from elastic boundaries.
Date Issued
2015-05-05
Date Acceptance
2015-02-25
Citation
Biomedical Optics Express, 2015, 6 (6), pp.1954-1962
ISSN
2156-7085
Publisher
Optical Society of America: Open Access Journals
Start Page
1954
End Page
1962
Journal / Book Title
Biomedical Optics Express
Volume
6
Issue
6
Copyright Statement
This is an open access article available at https://dx.doi.org/10.1364/BOE.6.001954
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (E
Grant Number
EP/H02316X/1
EP/K503733/1
Subjects
Science & Technology
Life Sciences & Biomedicine
Physical Sciences
Biochemical Research Methods
Optics
Radiology, Nuclear Medicine & Medical Imaging
Biochemistry & Molecular Biology
OPTICAL COHERENCE ELASTOGRAPHY
ACOUSTIC RADIATION FORCE
TOMOGRAPHY
BURSTS
FIELD
Publication Status
Published