Optical coherence elastography and its applications for the biomechanical characterization of tissues

Abstract

The biomechanical characterization of the tissues provides significant evidence for determining the pathological status and assessing the disease treatment. Incorporating elastography with optical coherence tomography (OCT), optical coherence elastography (OCE) can map the spatial elasticity distribution of biological tissue with high resolution. After the excitation with the external or inherent force, the tissue response of the deformation or vibration is detected by OCT imaging. The elastogram is assessed by stress–strain analysis, vibration amplitude measurements, and quantification of elastic wave velocities. OCE has been used for elasticity measurements in ophthalmology, endoscopy, and oncology, improving the precision of diagnosis and treatment of disease. In this article, we review the OCE methods for biomechanical characterization and summarize current OCE applications in biomedicine. The limitations and future development of OCE are also discussed during its translation to the clinic.

In vivo endoscopic optical coherence elastography based on a miniature probe

“…Based on phase-sensitive OCT (PhS-OCT), it enables the accurate measurement of 1-nm axial displacement by accurately capturing phase changes in spectral interferograms [ 15 ], showcasing exceptional sensitivity and precise quantification [ 16 , 17 ]. This positions OCE as a potent tool for early disease diagnosis by valuable insights into the intricate biomechanical properties of tissues at a microscopic level [ 18 ]. OCE has been reported to be used for ex vivo elasticity assessment of the human vaginal wall [ 19 ], providing real-time and high-accuracy elastic images, thus revealing the potential clinical application of OCE in the vagina.…”

Mapping the strain-stiffening behavior of the lung and lung cancer at microscale resolution using the crystal ribcage

“…Although elastography encompasses a broad range of techniques for assessing the material properties of biological tissues, each method presents limitations when addressing our specific problem ( Costa, 2004 ; De et al, 2010 ; Evans et al, 2012 ; Goenezen et al, 2012 ; Kennedy et al, 2014 ; Garra, 2015 ; Schregel et al, 2018 ; Seidl et al, 2020 ; Silva et al, 2020 ; Ghiuchici et al, 2021 ; Kuo et al, 2021 ; Wang et al, 2023 ). The gold-standard method for microscale elastography is atomic-force microscopy ( Krieg et al, 2018 ), which boasts extremely high-resolution, absolute measurements of stiffness.…”

“…Although strain elastography based on modalities like synchrotron microCT ( Cercos-Pita et al, 2022 ) have near-micron spatial resolution, to our knowledge, these methods lack the control and temporal resolution needed for tracking the same region of interest at alveolar resolution across changes in inflation pressure. Optical elastography ( Kennedy et al, 2014 ; Kennedy et al, 2017 ; Wang et al, 2023 ) offers an alternative method for more precisely estimating the displacements throughout a biological sample. For example, recent papers have implemented optical elastography based on digital image correlation (DIC) to quantify the lung’s strain ( Nelson et al, 2023 ) and stiffness ( Maghsoudi-Ganjeh et al, 2021 ); but in each case, the empirical method does not provide physiologically realistic boundary conditions, and the measurements are not at alveolar resolution.…”