Analysis of image formation in optical coherence elastography using a multiphysics approach.
IMAGE FORMATION IN OPTICAL COHERENCE ELASTOGRAPHY (OCE) RESULTS FROM A COMBINATION OF TWO PROCESSES: the mechanical deformation imparted to the sample and the detection of the resulting displacement using optical coherence tomography (OCT). We present a multiphysics model of these processes, validated by simulating strain elastograms acquired using phase-sensitive compression OCE, and demonstrating close correspondence with experimental results. Using the model, we present evidence that the approximation commonly used to infer sample displacement in phase-sensitive OCE is invalidated for smaller deformations than has been previously considered, significantly affecting the measurement precision, as quantified by the displacement sensitivity and the elastogram signal-to-noise ratio. We show how the precision of OCE is affected not only by OCT shot-noise, as is usually considered, but additionally by phase decorrelation due to the sample deformation. This multiphysics model provides a general framework that could be used to compare and contrast different OCE techniques.
Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Australia ; These authors contributed equally to this work.
Lixin
L
Chin
Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Australia ; These authors contributed equally to this work.
Andrea
A
Curatolo
Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Australia.
Brendan F
BF
Kennedy
Vascular Engineering, Intelligent Systems for Medicine Laboratory, School of Mechanical & Chemical Engineering, The University of Western Australia, Crawley, Australia ; Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK.
Barry J
BJ
Doyle
Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Australia ; Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, Crawley, Australia.
Peter R T
PR
Munro
Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Australia.
Robert A
RA
McLaughlin
Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Australia ; Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, Crawley, Australia.
David D
DD
Sampson
(000.3860) Mathematical methods in physics; (000.4430) Numerical approximation and analysis; (030.6140) Speckle; (110.2990) Image formation theory; (110.4500) Optical coherence tomography