51
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Vekilov DP, Singh M, Aglyamov SR, Larin KV, Grande-Allen KJ. Mapping the spatial variation of mitral valve elastic properties using air-pulse optical coherence elastography. J Biomech 2019; 93:52-59. [PMID: 31300156 PMCID: PMC10575695 DOI: 10.1016/j.jbiomech.2019.06.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 05/18/2019] [Accepted: 06/14/2019] [Indexed: 10/26/2022]
Abstract
The mitral valve is a highly heterogeneous tissue composed of two leaflets, anterior and posterior, whose unique composition and regional differences in material properties are essential to overall valve function. While mitral valve mechanics have been studied for many decades, traditional testing methods limit the spatial resolution of measurements and can be destructive. Optical coherence elastography (OCE) is an emerging method for measuring viscoelastic properties of tissues in a noninvasive, nondestructive manner. In this study, we employed air-pulse OCE to measure the spatial variation in mitral valve elastic properties with micro-scale resolution at 1 mm increments along the radial length of the leaflets. We analyzed differences between the leaflets, as well as between regions of the valve. We found that the anterior leaflet has a higher elastic wave velocity, which is reported as a surrogate for stiffness, than the posterior leaflet, most notably at the annular edge of the sample. In addition, we found a spatial elastic gradient in the anterior leaflet, where the annular edge was found to have a greater elastic wave velocity than the free edge. This gradient was less pronounced in the posterior leaflet. These patterns were confirmed using established uniaxial tensile testing methods. Overall, the anterior leaflet was stiffer and had greater heterogeneity in its mechanical properties than the posterior leaflet. This study measures differences between the two mitral leaflets with greater resolution than previously feasible and demonstrates a method that may be suitable for assessing valve mechanics following repair or during the engineering of synthetic valve replacements.
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Affiliation(s)
| | - Manmohan Singh
- University of Houston, Department of Biomedical Engineering, Houston, TX, United States
| | - Salavat R Aglyamov
- University of Houston, Department of Mechanical Engineering, Houston, TX, United States; University of Texas at Austin, Department of Biomedical Engineering, Austin, TX, United States
| | - Kirill V Larin
- University of Houston, Department of Biomedical Engineering, Houston, TX, United States
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52
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Nair A, Liu CH, Singh M, Das S, Le T, Du Y, Soomro S, Aglyamov S, Mohan C, Larin KV. Assessing colitis ex vivo using optical coherence elastography in a murine model. Quant Imaging Med Surg 2019; 9:1429-1440. [PMID: 31559172 PMCID: PMC6732062 DOI: 10.21037/qims.2019.06.03] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 05/30/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that causes regions of ulceration within the interior of the colon. UC is estimated to afflict hundreds of thousands of people in the United States alone. In addition to traditional colonoscopy, ultrasonic techniques can detect colitis, but have limited spatial resolution, which frequently results in underdiagnoses. Nevertheless, clinical diagnosis of colitis is still generally performed via colonoscopy. Optical techniques such as confocal microscopy and optical coherence tomography (OCT) have been proposed to detect UC with higher resolution. However, UC can potentially alter tissue biomechanical properties, providing additional contrast for earlier and potentially more accurate detection. Although clinically available elastography techniques have been immensely useful, they do not have the resolution for imaging small tissues, such as in small mammalian disease models. However, OCT-based elastography, optical coherence elastography (OCE), is well-suited for imaging the biomechanical properties of small mammal colon tissue. METHODS In this work, we induced elastic waves in ex vivo mouse colon tissue using a focused air-pulse. The elastic waves were detected using a phase-stabilized swept source OCE system, and the wave velocity was translated into stiffness. Measurements were taken at six positions for each sample to assess regional sample elasticity. Additional contrast between the control and diseased tissue was detected by analyzing the dispersion of the elastic wave and tissue optical properties obtained from the OCT structural image. RESULTS The results show distinct differences (P<0.05) in the stiffness between control and colitis disease samples, with a Young's modulus of 11.8±8.0 and 5.1±1.5 kPa, respectively. The OCT signal standard deviations for control and diseased samples were 5.8±0.3 and 5.5±0.2 dB, respectively. The slope of the OCT signal spatial frequency decay in the control samples was 92.7±10.0 and 87.3±4.7 dB∙µm in the colitis samples. The slope of the linearly fitted dispersion curve in the control samples was 1.5 mm, and 0.8 mm in the colitis samples. CONCLUSIONS Our results show that OCE can be utilized to distinguish tissue based on stiffness and optical properties. Our estimates of tissue stiffness suggest that the healthy colon tissue was stiffer than diseased tissue. Furthermore, structural analysis of the tissue indicates a distinct difference in tissue optical properties between the healthy and UC-like diseased tissue.
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Affiliation(s)
- Achuth Nair
- Department of Biomedical Engineering, University of Houston, Houston, TX, USA
| | - Chih Hao Liu
- Department of Biomedical Engineering, University of Houston, Houston, TX, USA
| | - Manmohan Singh
- Department of Biomedical Engineering, University of Houston, Houston, TX, USA
| | - Susobhan Das
- Department of Biomedical Engineering, University of Houston, Houston, TX, USA
| | - Triet Le
- Department of Biomedical Engineering, University of Houston, Houston, TX, USA
| | - Yong Du
- Department of Biomedical Engineering, University of Houston, Houston, TX, USA
| | - Sanam Soomro
- Department of Biomedical Engineering, University of Houston, Houston, TX, USA
| | - Salavat Aglyamov
- Department of Mechanical Engineering, University of Houston, Houston, TX, USA
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, USA
| | - Chandra Mohan
- Department of Biomedical Engineering, University of Houston, Houston, TX, USA
| | - Kirill V. Larin
- Department of Biomedical Engineering, University of Houston, Houston, TX, USA
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53
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Zvietcovich F, Ge GR, Mestre H, Giannetto M, Nedergaard M, Rolland JP, Parker KJ. Longitudinal shear waves for elastic characterization of tissues in optical coherence elastography. BIOMEDICAL OPTICS EXPRESS 2019; 10:3699-3718. [PMID: 31360610 PMCID: PMC6640829 DOI: 10.1364/boe.10.003699] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/30/2019] [Accepted: 06/11/2019] [Indexed: 05/10/2023]
Abstract
In dynamic optical coherence elastography (OCE), surface acoustic waves are the predominant perturbations. They constrain the quantification of elastic modulus to the direction of wave propagation only along the surface of tissues, and disregard elasticity gradients along depth. Longitudinal shear waves (LSW), on the other hand, can be generated at the surface of the tissue and propagate through depth with desirable properties for OCE: (1) LSW travel at the shear wave speed and can discriminate elasticity gradients along depth, and (2) the displacement of LSW is longitudinally polarized along the direction of propagation; therefore, it can be measured by a phase-sensitive optical coherence tomography system. In this study, we explore the capabilities of LSW generated by a circular glass plate in contact with a sample using numerical simulations and tissue-mimicking phantom experiments. Results demonstrate the potential of LSW in detecting an elasticity gradient along axial and lateral directions simultaneously. Finally, LSW are used for the elastography of ex vivo mouse brain and demonstrate important implications in in vivo and in situ measurements of local elasticity changes in brain and how they might correlate with the onset and progression of degenerative brain diseases.
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Affiliation(s)
- Fernando Zvietcovich
- Dept. of Electrical & Computer Engineering, University of Rochester, Rochester, NY 14627,
USA
| | - Gary R. Ge
- The Institute of Optics, University of Rochester, Rochester, NY 14627,
USA
| | - Humberto Mestre
- Center for Translational Neuromedicine, Dept. of Neurosurgery, University of Rochester, Rochester, NY 14642,
USA
| | - Michael Giannetto
- Center for Translational Neuromedicine, Dept. of Neurosurgery, University of Rochester, Rochester, NY 14642,
USA
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, Dept. of Neurosurgery, University of Rochester, Rochester, NY 14642,
USA
| | - Jannick P. Rolland
- The Institute of Optics, University of Rochester, Rochester, NY 14627,
USA
| | - Kevin J. Parker
- Dept. of Electrical & Computer Engineering, University of Rochester, Rochester, NY 14627,
USA
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54
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Pelivanov I, Gao L, Pitre J, Kirby MA, Song S, Li D, Shen TT, Wang RK, O’Donnell M. Does group velocity always reflect elastic modulus in shear wave elastography? JOURNAL OF BIOMEDICAL OPTICS 2019; 24:1-11. [PMID: 31342691 PMCID: PMC6650747 DOI: 10.1117/1.jbo.24.7.076003] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/08/2019] [Indexed: 05/04/2023]
Abstract
Dynamic elastography is an attractive method to evaluate tissue biomechanical properties. Recently, it was extended from US- and MR-based modalities to optical ones, such as optical coherence tomography for three-dimensional (3-D) imaging of propagating mechanical waves in subsurface regions of soft tissues, such as the eye. The measured group velocity is often used to convert wave speed maps into 3-D images of the elastic modulus distribution based on the assumption of bulk shear waves. However, the specific geometry of OCE measurements in bounded materials such as the cornea and skin calls into question elasticity reconstruction assuming a simple relationship between group velocity and shear modulus. We show that in layered media the bulk shear wave assumption results in highly underestimated shear modulus reconstructions and significant structural artifacts in modulus images. We urge the OCE community to be careful in using the group velocity to evaluate tissue elasticity and to focus on developing robust reconstruction methods to accurately reconstruct images of the shear elastic modulus in bounded media.
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Affiliation(s)
- Ivan Pelivanov
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
- Address all correspondence to Ivan Pelivanov, E-mail:
| | - Liang Gao
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - John Pitre
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Mitchell A. Kirby
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Shaozhen Song
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - David Li
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
- University of Washington, Department of Chemical Engineering, Seattle, Washington, United States
| | - Tueng T. Shen
- University of Washington, Department of Ophthalmology, Seattle, Washington, United States
| | - Ruikang K. Wang
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Matthew O’Donnell
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
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55
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Shao P, Eltony AM, Seiler TG, Tavakol B, Pineda R, Koller T, Seiler T, Yun SH. Spatially-resolved Brillouin spectroscopy reveals biomechanical abnormalities in mild to advanced keratoconus in vivo. Sci Rep 2019; 9:7467. [PMID: 31097778 PMCID: PMC6522517 DOI: 10.1038/s41598-019-43811-5] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 04/27/2019] [Indexed: 12/27/2022] Open
Abstract
Mounting evidence connects the biomechanical properties of tissues to the development of eye diseases such as keratoconus, a disease in which the cornea thins and bulges into a conical shape. However, measuring biomechanical changes in vivo with sufficient sensitivity for disease detection has proven challenging. Here, we demonstrate the diagnostic potential of Brillouin light-scattering microscopy, a modality that measures longitudinal mechanical modulus in tissues with high measurement sensitivity and spatial resolution. We have performed a study of 85 human subjects (93 eyes), consisting of 47 healthy volunteers and 38 keratoconus patients at differing stages of disease, ranging from stage I to stage IV. The Brillouin data in vivo reveal increasing biomechanical inhomogeneity in the cornea with keratoconus progression and biomechanical asymmetry between the left and right eyes at the onset of keratoconus. The receiver operating characteristic analysis of the stage-I patient data indicates that mean Brillouin shift of the cone performs better than corneal thickness and maximum curvature respectively. In conjunction with morphological patterns, Brillouin microscopy may add value for diagnosis of keratoconus and potentially for screening subjects at risk of complications prior to laser eye surgeries.
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Affiliation(s)
- Peng Shao
- Harvard Medical School and Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Amira M Eltony
- Harvard Medical School and Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Theo G Seiler
- Harvard Medical School and Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, 02114, USA.,Institute for Refractive and Ophthalmic Surgery (IROC), Zürich, 8002, Switzerland.,Universitätsklinik für Augenheilkunde, Inselspital, Bern, 3010, Switzerland
| | - Behrouz Tavakol
- Harvard Medical School and Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Roberto Pineda
- Massachusetts Eye and Ear Infirmary, Boston, MA, 02114, USA
| | - Tobias Koller
- Institute for Refractive and Ophthalmic Surgery (IROC), Zürich, 8002, Switzerland
| | - Theo Seiler
- Institute for Refractive and Ophthalmic Surgery (IROC), Zürich, 8002, Switzerland.
| | - Seok-Hyun Yun
- Harvard Medical School and Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, 02114, USA. .,Harvard-MIT Health Sciences and Technology, Cambridge, MA, 02139, USA.
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56
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Kazaili A, Lawman S, Geraghty B, Eliasy A, Zheng Y, Shen Y, Akhtar R. Line-Field Optical Coherence Tomography as a tool for In vitro characterization of corneal biomechanics under physiological pressures. Sci Rep 2019; 9:6321. [PMID: 31004101 PMCID: PMC6474860 DOI: 10.1038/s41598-019-42789-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 04/03/2019] [Indexed: 12/02/2022] Open
Abstract
There has been a lot of interest in accurately characterising corneal biomechanical properties under intraocular pressure (IOP) to help better understand ocular pathologies that are associated with elevated IOP. This study investigates the novel use of Line-Field Optical Coherence Tomography (LF-OCT) as an elastographic tool for accurately measuring mechanical properties of porcine corneas based on volumetric deformation following varying IOPs. A custom-built LF-OCT was used to measure geometrical and corneal surface displacement changes in porcine corneas under a range of IOPs, from 0-60 mmHg. Corneal thickness, elastic properties and hysteresis were calculated as a function of pressure. In addition, the effects of hydration were explored. We found that the elastic modulus increased in a linear fashion with IOP. Corneal thickness was found to reduce with IOP, decreasing 14% from 0 to 60 mmHg. Prolonged hydration in phosphate buffered saline (PBS) was found to significantly increase the elastic modulus and corneal hysteresis. Our study demonstrates that LF-OCT can be used to accurately measure the elastic properties based on volumetric deformation following physiological pressures. Furthermore, we show that prolonged hydration in PBS has a significant effect on the measured corneal properties.
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Affiliation(s)
- Ahmed Kazaili
- Department of Mechanical, Materials and Aerospace Engineering, School of Engineering, University of Liverpool, Liverpool, L69 3GH, UK
- Department of Biomedical Engineering, College of Engineering, University of Babylon, Hillah, Iraq
| | - Samuel Lawman
- Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool, L69 3GJ, UK
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L7 8TX, UK
| | - Brendan Geraghty
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L7 8TX, UK
| | - Ashkan Eliasy
- Department of Mechanical, Materials and Aerospace Engineering, School of Engineering, University of Liverpool, Liverpool, L69 3GH, UK
| | - Yalin Zheng
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L7 8TX, UK
| | - Yaochun Shen
- Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool, L69 3GJ, UK
| | - Riaz Akhtar
- Department of Mechanical, Materials and Aerospace Engineering, School of Engineering, University of Liverpool, Liverpool, L69 3GH, UK.
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57
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Sanderson RW, Curatolo A, Wijesinghe P, Chin L, Kennedy BF. Finger-mounted quantitative micro-elastography. BIOMEDICAL OPTICS EXPRESS 2019; 10:1760-1773. [PMID: 31086702 PMCID: PMC6484987 DOI: 10.1364/boe.10.001760] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 01/17/2019] [Accepted: 02/05/2019] [Indexed: 05/14/2023]
Abstract
We present a finger-mounted quantitative micro-elastography (QME) probe, capable of measuring the elasticity of biological tissue in a format that avails of the dexterity of the human finger. Finger-mounted QME represents the first demonstration of a wearable elastography probe. The approach realizes optical coherence tomography-based elastography by focusing the optical beam into the sample via a single-mode fiber that is fused to a length of graded-index fiber. The fiber is rigidly affixed to a 3D-printed thimble that is mounted on the finger. Analogous to manual palpation, the probe compresses the tissue through the force exerted by the finger. The resulting deformation is measured using optical coherence tomography. Elasticity is estimated as the ratio of local stress at the sample surface, measured using a compliant layer, to the local strain in the sample. We describe the probe fabrication method and the signal processing developed to achieve accurate elasticity measurements in the presence of motion artifact. We demonstrate the probe's performance in motion-mode scans performed on homogeneous, bi-layer and inclusion phantoms and its ability to measure a thermally-induced increase in elasticity in ex vivo muscle tissue. In addition, we demonstrate the ability to acquire 2D images with the finger-mounted probe where lateral scanning is achieved by swiping the probe across the sample surface.
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Affiliation(s)
- Rowan W. Sanderson
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, 6009, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia, 6009, Australia
| | - Andrea Curatolo
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, 6009, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia, 6009, Australia
- Current address: Visual Optics and Biophotonics Group, Instituto de Óptica “Daza de Valdés”, Consejo Superior de Investigaciones Cientificas (IO, CSIC), C/Serrano, 121, Madrid 28006, Spain
| | - Philip Wijesinghe
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, 6009, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia, 6009, Australia
- Current address: SUPA, School of Physics and Astronomy, University of St. Andrews, KY16 9SS, UK
| | - Lixin Chin
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, 6009, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia, 6009, Australia
| | - Brendan F. Kennedy
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, 6009, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia, 6009, Australia
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58
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Hepburn MS, Wijesinghe P, Chin L, Kennedy BF. Analysis of spatial resolution in phase-sensitive compression optical coherence elastography. BIOMEDICAL OPTICS EXPRESS 2019; 10:1496-1513. [PMID: 30891363 PMCID: PMC6420276 DOI: 10.1364/boe.10.001496] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/12/2019] [Accepted: 02/12/2019] [Indexed: 05/03/2023]
Abstract
Optical coherence elastography (OCE) is emerging as a method to image the mechanical properties of tissue on the microscale. However, the spatial resolution, a main advantage of OCE, has not been investigated and is not trivial to evaluate. To address this, we present a framework to analyze resolution in phase-sensitive compression OCE that incorporates the three main determinants of resolution: mechanical deformation of the sample, detection of this deformation using optical coherence tomography (OCT), and signal processing to estimate local axial strain. We demonstrate for the first time, through close correspondence between experiment and simulation of structured phantoms, that resolution in compression OCE is both spatially varying and sample dependent, which we link to the discrepancies between the model of elasticity and the mechanical deformation of the sample. We demonstrate that resolution is dependent on factors such as feature size and mechanical contrast. We believe that the analysis of image formation provided by our framework can expedite the development of compression OCE.
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Affiliation(s)
- Matt S. Hepburn
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia, 6009, Australia and Centre for Medical Research, The University of Western Australia, Crawley, Western Australia, 6009, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, 35, Stirling Highway, Perth, Western Australia, 6009, Australia
| | - Philip Wijesinghe
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia, 6009, Australia and Centre for Medical Research, The University of Western Australia, Crawley, Western Australia, 6009, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, 35, Stirling Highway, Perth, Western Australia, 6009, Australia
- Current address: SUPA, School of Physics and Astronomy, University of St. Andrews, KY16 9SS, UK
| | - Lixin Chin
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia, 6009, Australia and Centre for Medical Research, The University of Western Australia, Crawley, Western Australia, 6009, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, 35, Stirling Highway, Perth, Western Australia, 6009, Australia
| | - Brendan F. Kennedy
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia, 6009, Australia and Centre for Medical Research, The University of Western Australia, Crawley, Western Australia, 6009, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, 35, Stirling Highway, Perth, Western Australia, 6009, Australia
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59
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Zhang H, Wu C, Singh M, Nair A, Aglyamov SR, Larin KV. Optical coherence elastography of cold cataract in porcine lens. JOURNAL OF BIOMEDICAL OPTICS 2019; 24:1-7. [PMID: 30864348 PMCID: PMC6444576 DOI: 10.1117/1.jbo.24.3.036004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 02/19/2019] [Indexed: 05/08/2023]
Abstract
Cataract is one of the most prevalent causes of blindness around the world. Understanding the mechanisms of cataract development and progression is important for clinical diagnosis and treatment. Cold cataract has proven to be a robust model for cataract formation that can be easily controlled in the laboratory. There is evidence that the biomechanical properties of the lens can be significantly changed by cataract. Therefore, early detection of cataract, as well as evaluation of therapies, could be guided by characterization of lenticular biomechanical properties. In this work, we utilized optical coherence elastography (OCE) to monitor the changes in biomechanical properties of ex vivo porcine lenses during formation of cold cataract. Elastic waves were induced in the porcine lenses by a focused micro air-pulse while the lenses were cooled, and the elastic wave velocity was translated to Young's modulus of the lens. The results show an increase in the stiffness of the lens due to formation of the cold cataract (from 11.3 ± 3.4 to 21.8 ± 7.8 kPa). These results show a relation between lens opacity and stiffness and demonstrate that OCE can assess lenticular biomechanical properties and may be useful for detecting and potentially characterizing cataracts.
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Affiliation(s)
- Hongqiu Zhang
- University of Houston, Department of Biomedical Engineering, Houston, Texas, United States
| | - Chen Wu
- University of Houston, Department of Biomedical Engineering, Houston, Texas, United States
| | - Manmohan Singh
- University of Houston, Department of Biomedical Engineering, Houston, Texas, United States
| | - Achuth Nair
- University of Houston, Department of Biomedical Engineering, Houston, Texas, United States
| | - Salavat R. Aglyamov
- University of Houston, Department of Mechanical Engineering, Houston, Texas, United States
- University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Kirill V. Larin
- University of Houston, Department of Biomedical Engineering, Houston, Texas, United States
- Address all correspondence to Kirill V. Larin, E-mail:
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60
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Zorgani A, Ghafour TA, Lescanne M, Catheline S, Bel-Brunon A. Optical elastography: tracking surface waves with digital image correlation. Phys Med Biol 2019; 64:055007. [PMID: 30673652 DOI: 10.1088/1361-6560/ab0141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Elastography consists in evaluating the propagation speed of waves into a tissue to estimate its stiffness. Usually this method is based on Ultrasounds, magnetic resonance imaging or optical coherent tomography. This paper proposes a simple optic method using ultrafast cameras. Based on digital image correlation (DIC), the tracking of elastic surface wave from white light intensity pattern, allows estimating the propagation speed as an indicator of the tissue local stiffness. Two configurations are presented: (1) 2D imaging of a flat phantom surface with a single camera and (2) 3D imaging of a curved phantom surface with two cameras. As a feasibility study of the first configuration, surface wave speed was measured on isotropic and anisotropic phantoms. Comparisons with ultrasound methods fully validate this approach. Although more sophisticated, the second configuration account for propagation distortions caused by locally curved topology. Triangulation techniques used to retrieve local topology are named stereo-correlation in the field of biomechanics. Stereo-elastography is thus proposed to determine tissue local elasticity from any soft tissue surface wave.
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Affiliation(s)
- Ali Zorgani
- LabTAU, INSERM, Centre Léon Bérard, Université Lyon 1, Univ Lyon, F-69003, LYON, France. Author to whom any correspondence should be addressed
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61
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Ling Y, Meiniel W, Singh-Moon R, Angelini E, Olivo-Marin JC, Hendon CP. Compressed sensing-enabled phase-sensitive swept-source optical coherence tomography. OPTICS EXPRESS 2019; 27:855-871. [PMID: 30696165 PMCID: PMC6410915 DOI: 10.1364/oe.27.000855] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 11/30/2018] [Accepted: 12/21/2018] [Indexed: 05/21/2023]
Abstract
Here we present a novel phase-sensitive swept-source optical coherence tomography (PhS-SS-OCT) system. The simultaneously recorded calibration signal, which is commonly used in SS-OCT to stabilize the phase, is randomly sub-sampled during the acquisition, and it is later reconstructed based on the Compressed Sensing (CS) theory. We first mathematically investigated the method, and verified it through computer simulations. We then conducted a vibrational frequency test and a flow velocity measurement in phantoms to demonstrate the system's capability of handling phase-sensitive tasks. The proposed scheme shows excellent phase stability with greatly discounted data bandwidth compared with conventional procedures. We further showcased the usefulness of the system in biological samples by detecting the blood flow in ex vivo swine left marginal artery. The proposed system is compatible with most of the existing SS-OCT systems and could be a preferred solution for future high-speed phase-sensitive applications.
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Affiliation(s)
- Yuye Ling
- Department of Electrical Engineering, Columbia University, 500 W 120th St., New York, New York 10027,
USA
| | - William Meiniel
- Institut Mines-Telecom, Telecom-ParisTech, CNRS LTCI, Paris,
France
- Institut Pasteur, BioImage Analysis unit, CNRS UMR 3691, Paris,
France
| | - Rajinder Singh-Moon
- Department of Electrical Engineering, Columbia University, 500 W 120th St., New York, New York 10027,
USA
| | - Elsa Angelini
- Institut Mines-Telecom, Telecom-ParisTech, CNRS LTCI, Paris,
France
- NIHR Imperial BRC, ITMAT Data Science Group, Imperial College, London,
United Kingdom
- Department of Biomedical Engineering, Columbia University, 500 W 120th St., New York, New York 10027,
USA
| | | | - Christine P. Hendon
- Department of Electrical Engineering, Columbia University, 500 W 120th St., New York, New York 10027,
USA
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He Y, Qu Y, Zhu J, Zhang Y, Saidi A, Ma T, Zhou Q, Chen Z. Confocal Shear Wave Acoustic Radiation Force Optical Coherence Elastography for Imaging and Quantification of the In Vivo Posterior Eye. IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS : A PUBLICATION OF THE IEEE LASERS AND ELECTRO-OPTICS SOCIETY 2019; 25:10.1109/jstqe.2018.2834435. [PMID: 32042240 PMCID: PMC7008613 DOI: 10.1109/jstqe.2018.2834435] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Retinal diseases, such as age-related macular degeneration (AMD), are the leading cause of blindness in the elderly population. Since no known cures are currently present, it is crucial to diagnose the condition in its early stages so that disease progression is monitored. Recent advances show that the mechanical elasticity of the posterior eye changes with the onset of AMD. In this work, we present a quantitative method of mapping the mechanical elasticity of the posterior eye using confocal shear wave acoustic radiation force optical coherence elastography (SW-ARF-OCE). This technique has been developed and validated with both an ex-vivo porcine tissue model and a customized in-vivo rabbit model, which both showed the quantified elasticity variations between different layers. This study verifies the feasibility of using this technology for the quantification and diagnosis of retinal diseases from the in-vivo posterior eye.
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Affiliation(s)
- Youmin He
- Department of Biomedical Engineering and the Beckman Laser Institute, University of California, Irvine, CA 92697 USA
| | - Yueqiao Qu
- Department of Biomedical Engineering and the Beckman Laser Institute, University of California, Irvine, CA 92697 USA
| | - Jiang Zhu
- Department of Biomedical Engineering and the Beckman Laser Institute, University of California, Irvine, CA 92697 USA
| | - Yi Zhang
- Roski Eye Institute, Department of Ophthalmology and Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Arya Saidi
- Marshall B. Ketchum University. Southern California College of Optometry, 2575 Yorba Linda Blvd, Fullerton, CA 92831 USA
| | - Teng Ma
- Roski Eye Institute, Department of Ophthalmology and Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Qifa Zhou
- Roski Eye Institute, Department of Ophthalmology and Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Zhongping Chen
- Department of Biomedical Engineering and the Beckman Laser Institute, University of California, Irvine, CA 92697 USA
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63
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Zhu J, He X, Chen Z. Acoustic radiation force optical coherence elastography for elasticity assessment of soft tissues. APPLIED SPECTROSCOPY REVIEWS 2019; 54:457-481. [PMID: 31749516 PMCID: PMC6867804 DOI: 10.1080/05704928.2018.1467436] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Biomechanical properties of soft tissues are important indicators of tissue functions which can be used for clinical diagnosis and disease monitoring. Elastography, incorporating the principles of elasticity measurements into imaging modalities, provides quantitative assessment of elastic properties of biological tissues. Benefiting from high-resolution, noninvasive and three-dimensional optical coherence tomography (OCT), optical coherence elastography (OCE) is an emerging optical imaging modality to characterize and map biomechanical properties of soft tissues. Recently, acoustic radiation force (ARF) OCE has been developed for elasticity measurements of ocular tissues, detection of vascular lesions and monitoring of blood coagulation based on remote and noninvasive ARF excitation to both internal and superficial tissues. Here, we describe the advantages of the ARF-OCE technique, the measurement methods in ARF-OCE, the applications in biomedical detection, current challenges and advances. ARF-OCE technology has the potential to become a powerful tool for in vivo elasticity assessment of biological samples in a non-contact, non-invasive and high-resolution nature.
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Affiliation(s)
- Jiang Zhu
- Beckman Laser Institute, University of California, Irvine, Irvine, California 92612, USA
| | - Xingdao He
- Key Laboratory of Nondestructive Test (Ministry of Education), Nanchang Hangkong University, Nanchang 330063, China
| | - Zhongping Chen
- Beckman Laser Institute, University of California, Irvine, Irvine, California 92612, USA
- Key Laboratory of Nondestructive Test (Ministry of Education), Nanchang Hangkong University, Nanchang 330063, China
- Department of Biomedical Engineering, University of California, Irvine, Irvine, California 92697, USA
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Wu C, Aglyamov SR, Han Z, Singh M, Liu CH, Larin KV. Assessing the biomechanical properties of the porcine crystalline lens as a function of intraocular pressure with optical coherence elastography. BIOMEDICAL OPTICS EXPRESS 2018; 9:6455-6466. [PMID: 31065442 PMCID: PMC6491010 DOI: 10.1364/boe.9.006455] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 11/11/2018] [Accepted: 11/14/2018] [Indexed: 05/04/2023]
Abstract
In this study, we investigated the relationship between the biomechanical properties of the crystalline lens and intraocular pressure (IOP) using a confocal acoustic radiation force (ARF) and phase-sensitive optical coherence elastography (OCE) system. ARF induced a small displacement at the apex of porcine lenses in situ at various artificially controlled IOPs. Maximum displacement, relaxation rate, and Young's modulus were utilized to assess the stiffness of the crystalline lens. The results showed that the stiffness of the crystalline increased as IOP increased, but the lens stiffening was not as significant as the stiffening of other ocular tissues such as the cornea and the sclera. A mechanical hysteresis in the lens was also observed while cycling IOP, indicating that the viscoelastic response of the lens is crucial to fully understanding its biomechanical properties.
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Affiliation(s)
- Chen Wu
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
| | - Salavat R Aglyamov
- Department of Mechanical Engineering, University of Houston, Houston, TX 77204, USA
- Department of Biomedical Engineering, University of Texas, Austin, TX 78712, USA
| | - Zhaolong Han
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
- School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Manmohan Singh
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
| | - Chih-Hao Liu
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
| | - Kirill V Larin
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
- Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, Russia
- Molecular Physiology and Biophysics, Baylor College of Medicine, TX 77584, USA
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Nair A, Liu CH, Das S, Ho T, Du Y, Soomro S, Mohan C, Larin KV. Detecting murine Inflammatory Bowel Disease using Optical Coherence Elastography. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2018; 2018:830-833. [PMID: 30440520 DOI: 10.1109/embc.2018.8512295] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that causes regions of ulceration within the interior of the colon. UC is estimated to afflict hundreds of thousands of people in the United States alone. Ultrasonic techniques can detect colitis, but have limited spatial resolution, which frequently results in underdiagnoses. Nevertheless, clinical diagnosis of colitis is still generally performed via colonoscopy. Optical techniques such as confocal microscopy and optical coherence tomography (OCT) have been proposed as higher resolution alternative imaging modalities to detect colitis. Additionally, IBD can potentially alter tissue biomechanical properties, which cannot be quantified from structural imaging alone. Elastography is a potential method to assess colon biomechanical properties to provide additional contrast for distinguishing healthy and diseased colon tissue. In this work, we induced elastic waves in ex vivo mouse colon tissue using a focused air-pulse. The elastic waves were detected using a phase-stabilized swept source optical coherence elastography system, and the wave velocity was translated into stiffness. Measurements were taken at six random positions for each sample in order to assess regional sample elasticity. The results show distinct differences ($p \lt 0.05$) in the stiffness between healthy and IBD-diseased samples, with a Young's Modulus of $10.2 \pm 3.7$ kPa and $4.9 \pm 0.3$ kPa, respectively. Dispersion analysis presents another parameter to distinguish tissue health. The high frequency components of the phase velocity dispersion curve indicate a variation between healthy and IBD colonic tissue. Our results show that OCE may be useful for detecting IBD noninvasively.
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Karpiouk AB, VanderLaan DJ, Larin KV, Emelianov SY. Integrated optical coherence tomography and multielement ultrasound transducer probe for shear wave elasticity imaging of moving tissues. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-7. [PMID: 30369107 PMCID: PMC6210783 DOI: 10.1117/1.jbo.23.10.105006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 09/25/2018] [Indexed: 05/18/2023]
Abstract
Accurate measurements of microelastic properties of soft tissues in-vivo using optical coherence elastography can be affected by motion artifacts caused by cardiac and respiratory cycles. This problem can be overcome using a multielement ultrasound transducer probe where each ultrasound transducer is capable of generating acoustic radiation force (ARF) and, therefore, creating shear waves in tissue. These shear waves, produced during the phase of cardiac and respiratory cycles when tissues are effectively stationary, are detected at the same observation point using phase-sensitive optical coherence tomography (psOCT). Given the known distance between the ultrasound transducers, the speed of shear wave propagation can be calculated by measuring the difference between arrival times of shear waves. The combined multitransducer ARF/psOCT probe has been designed and tested in phantoms and ex-vivo studies using fresh rabbit heart. The measured values of shear moduli are in good agreement with those reported in literature. Our results suggest that the developed multitransducer ARF/psOCT probe can be useful for many in-vivo applications, including quantifying the microelasticity of cardiac muscle.
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Affiliation(s)
- Andrei B. Karpiouk
- Georgia Institute of Technology, Electrical and Computer Engineering Department, Atlanta, Georgia, United States
| | - Donald J. VanderLaan
- Georgia Institute of Technology, Electrical and Computer Engineering Department, Atlanta, Georgia, United States
| | - Kirill V. Larin
- University of Houston, Biomedical Engineering Department, Houston, Texas, United States
- Tomsk State University, Interdisciplinary Laboratory of Biophotonics, Tomsk, Russia
| | - Stanislav Y. Emelianov
- Georgia Institute of Technology, Electrical and Computer Engineering Department, Atlanta, Georgia, United States
- Georgia Institute of Technology and Emory University, School of Medicine, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
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Shih CC, Qian X, Ma T, Han Z, Huang CC, Zhou Q, Shung KK. Quantitative Assessment of Thin-Layer Tissue Viscoelastic Properties Using Ultrasonic Micro-Elastography With Lamb Wave Model. IEEE TRANSACTIONS ON MEDICAL IMAGING 2018; 37:1887-1898. [PMID: 29993652 DOI: 10.1109/tmi.2018.2820157] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Characterizing the viscoelastic properties of thin-layer tissues with micro-level thickness has long remained challenging. Recently, several micro-elastography techniques have been developed to improve the spatial resolution. However, most of these techniques have not considered the medium boundary conditions when evaluating the viscoelastic properties of thin-layer tissues such as arteries and corneas; this might lead to estimation bias or errors. This paper aims to integrate the Lamb wave model with our previously developed ultrasonic micro-elastography imaging system for obtaining accurate viscoelastic properties in thin-layer tissues. A 4.5-MHz ring transducer was used to generate an acoustic radiation force for inducing tissue displacements to produce guided wave, and the wave propagation was detected using a confocally aligned 40-MHz needle transducer. The phase velocity and attenuation were obtained from k-space by both the impulse and the harmonic methods. The measured phase velocity was fit using the Lamb wave model with the Kelvin-Voigt model. Phantom experiments were conducted using 7% and 12% gelatin and 1.5% agar phantoms with different thicknesses (2, 3, and 4 mm). Biological experiments were performed on porcine cornea and rabbit carotid artery ex vivo. Thin-layer phantoms with different thicknesses were confirmed to have the same elasticity; this was consistent with the estimates of bulk phantoms from mechanical tests and the shear wave rheological model. The trend of the measured attenuations was also confirmed with the viscosity results obtained using the Lamb wave model. Through the impulse and harmonic methods, the shear viscoelasticity values were estimated to be 8.2 kPa for $0.9~\text {Pa}{\cdot} \text {s}$ and 9.6 kPa for $0.8~\text {Pa}{\cdot} \text {s}$ in the cornea and 27.9 kPa for $0.1~\text {Pa}\cdot \text {s}$ and 26.5 kPa for $0.1~\text {Pa}\cdot \text {s}$ in the artery.
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69
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Singh M, Han Z, Li J, Vantipalli S, Aglyamov SR, Twa MD, Larin KV. Quantifying the effects of hydration on corneal stiffness with noncontact optical coherence elastography. J Cataract Refract Surg 2018; 44:1023-1031. [PMID: 30049567 DOI: 10.1016/j.jcrs.2018.03.036] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 02/17/2018] [Accepted: 03/20/2018] [Indexed: 01/08/2023]
Abstract
PURPOSE To quantify the effects of the hydration state on the Young's modulus of the cornea. SETTING Biomedical Optics Laboratory, University of Houston, Houston, Texas, USA. DESIGN Experimental study. METHODS Noncontact, dynamic optical coherence elastography (OCE) measurements were taken of in situ rabbit corneas in the whole eye-globe configuration (n = 10) and at an artificially controlled intraocular pressure of 15 mm Hg. Baseline OCE measurements were taken by topically hydrating the corneas with saline for 1 hour. The corneas were then dehydrated topically with a 20% dextran solution for another hour, and the OCE measurements were repeated. A finite element method was used to quantify the Young's modulus of the corneas based on the OCE measurements. RESULTS The thickness of the corneas shrank considerably after topical addition of the 20% dextran solution (∼680 μm to ∼370 μm), and the OCE-measured elastic-wave speed correspondingly decreased (∼3.2 m/s to ∼2.6 m/s). The finite element method results showed an increase in Young's modulus (500 kPa to 800 kPa) resulting from dehydration and subsequent thinning. CONCLUSION Young's modulus increased significantly as the corneas dehydrated and thinned, showing that corneal geometry and hydration state are critical factors for accurately quantifying corneal biomechanical properties.
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Affiliation(s)
- Manmohan Singh
- From Biomedical Engineering (Singh, Li, Larin) and the College of Optometry (Vantipalli), Mechanical Engineering (Aglyamov), University of Houston, and Molecular Physiology and Biophysics (Larin), Baylor College of Medicine, Houston, Texas, and the School of Optometry (Twa) and Biomedical Engineering (Twa), University of Alabama at Birmingham, Birmingham, Alabama, USA; The School of Naval Architecture (Han), Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China; Interdisciplinary Laboratory of Biophotonics (Larin), Tomsk State University, Tomsk, Russia
| | - Zhaolong Han
- From Biomedical Engineering (Singh, Li, Larin) and the College of Optometry (Vantipalli), Mechanical Engineering (Aglyamov), University of Houston, and Molecular Physiology and Biophysics (Larin), Baylor College of Medicine, Houston, Texas, and the School of Optometry (Twa) and Biomedical Engineering (Twa), University of Alabama at Birmingham, Birmingham, Alabama, USA; The School of Naval Architecture (Han), Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China; Interdisciplinary Laboratory of Biophotonics (Larin), Tomsk State University, Tomsk, Russia
| | - Jiasong Li
- From Biomedical Engineering (Singh, Li, Larin) and the College of Optometry (Vantipalli), Mechanical Engineering (Aglyamov), University of Houston, and Molecular Physiology and Biophysics (Larin), Baylor College of Medicine, Houston, Texas, and the School of Optometry (Twa) and Biomedical Engineering (Twa), University of Alabama at Birmingham, Birmingham, Alabama, USA; The School of Naval Architecture (Han), Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China; Interdisciplinary Laboratory of Biophotonics (Larin), Tomsk State University, Tomsk, Russia
| | - Srilatha Vantipalli
- From Biomedical Engineering (Singh, Li, Larin) and the College of Optometry (Vantipalli), Mechanical Engineering (Aglyamov), University of Houston, and Molecular Physiology and Biophysics (Larin), Baylor College of Medicine, Houston, Texas, and the School of Optometry (Twa) and Biomedical Engineering (Twa), University of Alabama at Birmingham, Birmingham, Alabama, USA; The School of Naval Architecture (Han), Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China; Interdisciplinary Laboratory of Biophotonics (Larin), Tomsk State University, Tomsk, Russia
| | - Salavat R Aglyamov
- From Biomedical Engineering (Singh, Li, Larin) and the College of Optometry (Vantipalli), Mechanical Engineering (Aglyamov), University of Houston, and Molecular Physiology and Biophysics (Larin), Baylor College of Medicine, Houston, Texas, and the School of Optometry (Twa) and Biomedical Engineering (Twa), University of Alabama at Birmingham, Birmingham, Alabama, USA; The School of Naval Architecture (Han), Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China; Interdisciplinary Laboratory of Biophotonics (Larin), Tomsk State University, Tomsk, Russia
| | - Michael D Twa
- From Biomedical Engineering (Singh, Li, Larin) and the College of Optometry (Vantipalli), Mechanical Engineering (Aglyamov), University of Houston, and Molecular Physiology and Biophysics (Larin), Baylor College of Medicine, Houston, Texas, and the School of Optometry (Twa) and Biomedical Engineering (Twa), University of Alabama at Birmingham, Birmingham, Alabama, USA; The School of Naval Architecture (Han), Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China; Interdisciplinary Laboratory of Biophotonics (Larin), Tomsk State University, Tomsk, Russia
| | - Kirill V Larin
- From Biomedical Engineering (Singh, Li, Larin) and the College of Optometry (Vantipalli), Mechanical Engineering (Aglyamov), University of Houston, and Molecular Physiology and Biophysics (Larin), Baylor College of Medicine, Houston, Texas, and the School of Optometry (Twa) and Biomedical Engineering (Twa), University of Alabama at Birmingham, Birmingham, Alabama, USA; The School of Naval Architecture (Han), Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China; Interdisciplinary Laboratory of Biophotonics (Larin), Tomsk State University, Tomsk, Russia.
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Zhu J, Yu J, Qu Y, He Y, Li Y, Yang Q, Huo T, He X, Chen Z. Coaxial excitation longitudinal shear wave measurement for quantitative elasticity assessment using phase-resolved optical coherence elastography. OPTICS LETTERS 2018; 43:2388-2391. [PMID: 29762599 DOI: 10.1364/ol.43.002388] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Optical coherence elastography (OCE) is an emerging imaging modality for the assessment of mechanical properties in soft tissues. Transverse shear wave measurements using OCE can quantify the elastic moduli perpendicular to the force direction, however, missing the elastic information along the force direction. In this study, we developed coaxial excitation longitudinal shear wave measurements for quantification of elastic moduli along the force direction using M-scans. Incorporating Rayleigh wave measurements using non-coaxial lateral scans into longitudinal shear wave measurements, directionally dependent elastic properties can be quantified along the force direction and perpendicular to the force direction. Therefore, the reported system has the capability to image elasticity of anisotropic biological tissues.
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71
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Wang K, Li G, Read AT, Navarro I, Mitra AK, Stamer WD, Sulchek T, Ethier CR. The relationship between outflow resistance and trabecular meshwork stiffness in mice. Sci Rep 2018; 8:5848. [PMID: 29643342 PMCID: PMC5895808 DOI: 10.1038/s41598-018-24165-w] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 03/26/2018] [Indexed: 11/25/2022] Open
Abstract
It has been suggested that common mechanisms may underlie the pathogenesis of primary open-angle glaucoma (POAG) and steroid-induced glaucoma (SIG). The biomechanical properties (stiffness) of the trabecular meshwork (TM) have been shown to differ between POAG patients and unaffected individuals. While features such as ocular hypertension and increased outflow resistance in POAG and SIG have been replicated in mouse models, whether changes of TM stiffness contributes to altered IOP homeostasis remains unknown. We found that outer TM was stiffer than the inner TM and, there was a significant positive correlation between outflow resistance and TM stiffness in mice where conditions are well controlled. This suggests that TM stiffness is intimately involved in establishing outflow resistance, motivating further studies to investigate factors underlying TM biomechanical property regulation. Such factors may play a role in the pathophysiology of ocular hypertension. Additionally, this finding may imply that manipulating TM may be a promising approach to restore normal outflow dynamics in glaucoma. Further, novel technologies are being developed to measure ocular tissue stiffness in situ. Thus, the changes of TM stiffness might be a surrogate marker to help in diagnosing altered conventional outflow pathway function if those technologies could be adapted to TM.
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Affiliation(s)
- Ke Wang
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, 30332, United States of America
| | - Guorong Li
- Department of Ophthalmology, Duke University, Durham, North Carolina, 27708, United States of America
| | - A Thomas Read
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, 30332, United States of America
| | - Iris Navarro
- Department of Ophthalmology, Duke University, Durham, North Carolina, 27708, United States of America
| | - Ashim K Mitra
- School of Pharmacy, University of Missouri-Kansas City, Kansas City, Missouri, 64110, United States of America
| | - W Daniel Stamer
- Department of Ophthalmology, Duke University, Durham, North Carolina, 27708, United States of America
| | - Todd Sulchek
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia, 30332, United States of America
| | - C Ross Ethier
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, 30332, United States of America. .,George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia, 30332, United States of America.
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Wang S, Singh M, Tran TT, Leach J, Aglyamov SR, Larina IV, Martin JF, Larin KV. Biomechanical assessment of myocardial infarction using optical coherence elastography. BIOMEDICAL OPTICS EXPRESS 2018; 9:728-742. [PMID: 29552408 PMCID: PMC5854074 DOI: 10.1364/boe.9.000728] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 12/26/2017] [Accepted: 12/27/2017] [Indexed: 05/18/2023]
Abstract
Myocardial infarction (MI) leads to cardiomyocyte loss, impaired cardiac function, and heart failure. Molecular genetic analyses of myocardium in mouse models of ischemic heart disease have provided great insight into the mechanisms of heart regeneration, which is promising for novel therapies after MI. Although biomechanical factors are considered an important aspect in cardiomyocyte proliferation, there are limited methods for mechanical assessment of the heart in the mouse MI model. This prevents further understanding the role of tissue biomechanics in cardiac regeneration. Here we report optical coherence elastography (OCE) of the mouse heart after MI. Surgical ligation of the left anterior descending coronary artery was performed to induce an infarction in the heart. Two OCE methods with assessment of the direction-dependent elastic wave propagation and the spatially resolved displacement damping provide complementary analyses of the left ventricle. In comparison with sham, the infarcted heart features a fibrotic scar region with reduced elastic wave velocity, decreased natural frequency, and less mechanical anisotropy at the tissue level at the sixth week post-MI, suggesting lower and more isotropic stiffness. Our results indicate that OCE can be utilized for nondestructive biomechanical characterization of MI in the mouse model, which could serve as a useful tool in the study of heart repair.
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Affiliation(s)
- Shang Wang
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
- Equal contribution
| | - Manmohan Singh
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas 77204, USA
- Equal contribution
| | - Thuy Tien Tran
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
| | - John Leach
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
| | - Salavat R. Aglyamov
- Department of Mechanical Engineering, University of Houston, 4726 Calhoun Road, Houston, Texas 77204, USA
| | - Irina V. Larina
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
| | - James F. Martin
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
- The Texas Heart Institute, 6770 Bertner Avenue, Houston, Texas 77030, USA
| | - Kirill V. Larin
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas 77204, USA
- Interdisciplinary Laboratory of Biophotonics, Tomsk State University, 36 Lenin Ave., Tomsk 634050, Russia
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Loehr JA, Wang S, Cully TR, Pal R, Larina IV, Larin KV, Rodney GG. NADPH oxidase mediates microtubule alterations and diaphragm dysfunction in dystrophic mice. eLife 2018; 7:31732. [PMID: 29381135 PMCID: PMC5812717 DOI: 10.7554/elife.31732] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 01/20/2018] [Indexed: 12/18/2022] Open
Abstract
Skeletal muscle from mdx mice is characterized by increased Nox2 ROS, altered microtubule network, increased muscle stiffness, and decreased muscle/respiratory function. While microtubule de-tyrosination has been suggested to increase stiffness and Nox2 ROS production in isolated single myofibers, its role in altering tissue stiffness and muscle function has not been established. Because Nox2 ROS production is upregulated prior to microtubule network alterations and ROS affect microtubule formation, we investigated the role of Nox2 ROS in diaphragm tissue microtubule organization, stiffness and muscle/respiratory function. Eliminating Nox2 ROS prevents microtubule disorganization and reduces fibrosis and muscle stiffness in mdx diaphragm. Fibrosis accounts for the majority of variance in diaphragm stiffness and decreased function, implicating altered extracellular matrix and not microtubule de-tyrosination as a modulator of diaphragm tissue function. Ultimately, inhibiting Nox2 ROS production increased force and respiratory function in dystrophic diaphragm, establishing Nox2 as a potential therapeutic target in Duchenne muscular dystrophy.
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Affiliation(s)
- James Anthony Loehr
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, United States
| | - Shang Wang
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, United States
| | - Tanya R Cully
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, United States
| | - Rituraj Pal
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, United States
| | - Irina V Larina
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, United States
| | - Kirill V Larin
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, United States.,Department of Biomedical Engineering, University of Houston, Houston, United States.,Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, Russia
| | - George G Rodney
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, United States
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Abstract
Optical coherence tomography (OCT) is a high-resolution, three-dimensional, noninvasive imaging modality to examine the human retina. Since the introduction of spectral domain (SD-) OCT-the currently most used variant of OCT-previously unknown details of in vivo retinal morphology of a broad variety of pathologies have become visible. This chapter explains the basic principles of the OCT technology, deals with possible pitfalls in OCT examination or analysis, and hints at the use of OCT technology in functional imaging.
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Affiliation(s)
- Thomas Theelen
- Department of Ophthalmology, Radboud University Medical Center (Radboudumc), Nijmegen, The Netherlands.
| | - Michel M Teussink
- Department of Ophthalmology, Radboud University Medical Center (Radboudumc), Nijmegen, The Netherlands
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Wijesinghe P, Johansen NJ, Curatolo A, Sampson DD, Ganss R, Kennedy BF. Ultrahigh-Resolution Optical Coherence Elastography Images Cellular-Scale Stiffness of Mouse Aorta. Biophys J 2018; 113:2540-2551. [PMID: 29212007 DOI: 10.1016/j.bpj.2017.09.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 08/22/2017] [Accepted: 09/19/2017] [Indexed: 01/08/2023] Open
Abstract
Cellular-scale imaging of the mechanical properties of tissue has helped to reveal the origins of disease; however, cellular-scale resolution is not readily achievable in intact tissue volumes. Here, we demonstrate volumetric imaging of Young's modulus using ultrahigh-resolution optical coherence elastography, and apply it to characterizing the stiffness of mouse aortas. We achieve isotropic resolution of better than 15 μm over a 1-mm lateral field of view through the entire depth of an intact aortic wall. We employ a method of quasi-static compression elastography that measures volumetric axial strain and uses a compliant, transparent layer to measure surface axial stress. This combination is used to estimate Young's modulus throughout the volume. We demonstrate differentiation by stiffness of individual elastic lamellae and vascular smooth muscle. We observe stiffening of the aorta in regulator of G protein signaling 5-deficient mice, a model that is linked to vascular remodeling and fibrosis. We observe increased stiffness with proximity to the heart, as well as regions with micro-structural and micro-mechanical signatures characteristic of fibrous and lipid-rich tissue. High-resolution imaging of Young's modulus with optical coherence elastography may become an important tool in vascular biology and in other fields concerned with understanding the role of mechanics within the complex three-dimensional architecture of tissue.
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Affiliation(s)
- Philip Wijesinghe
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, Australia; Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, Perth, Western Australia, Australia.
| | - Niloufer J Johansen
- Centre for Medical Research, The University of Western Australia, Perth, Western Australia, Australia; Research Department, St John of God Subiaco Hospital, Subiaco, Western Australia, Australia
| | - Andrea Curatolo
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, Australia; School of Electrical, Electronic and Computer Engineering, The University of Western Australia, Perth, Western Australia, Australia
| | - David D Sampson
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, Perth, Western Australia, Australia; Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Perth, Western Australia, Australia
| | - Ruth Ganss
- Vascular Biology and Stromal Targeting, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, Australia
| | - Brendan F Kennedy
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, Australia; School of Electrical, Electronic and Computer Engineering, The University of Western Australia, Perth, Western Australia, Australia
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76
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Kirby MA, Pelivanov I, Song S, Ambrozinski Ł, Yoon SJ, Gao L, Li D, Shen TT, Wang RK, O’Donnell M. Optical coherence elastography in ophthalmology. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:1-28. [PMID: 29275544 PMCID: PMC5745712 DOI: 10.1117/1.jbo.22.12.121720] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 12/14/2017] [Indexed: 05/03/2023]
Abstract
Optical coherence elastography (OCE) can provide clinically valuable information based on local measurements of tissue stiffness. Improved light sources and scanning methods in optical coherence tomography (OCT) have led to rapid growth in systems for high-resolution, quantitative elastography using imaged displacements and strains within soft tissue to infer local mechanical properties. We describe in some detail the physical processes underlying tissue mechanical response based on static and dynamic displacement methods. Namely, the assumptions commonly used to interpret displacement and strain measurements in terms of tissue elasticity for static OCE and propagating wave modes in dynamic OCE are discussed with the ultimate focus on OCT system design for ophthalmic applications. Practical OCT motion-tracking methods used to map tissue elasticity are also presented to fully describe technical developments in OCE, particularly noting those focused on the anterior segment of the eye. Clinical issues and future directions are discussed in the hope that OCE techniques will rapidly move forward to translational studies and clinical applications.
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Affiliation(s)
- Mitchell A. Kirby
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Ivan Pelivanov
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Shaozhen Song
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Łukasz Ambrozinski
- Akademia Górniczo-Hutnicza University of Science and Technology, Krakow, Poland
| | - Soon Joon Yoon
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Liang Gao
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - David Li
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
- University of Washington, Department of Chemical Engineering, Seattle, Washington, United States
| | - Tueng T. Shen
- University of Washington, Department of Ophthalmology, Seattle, Washington, United States
| | - Ruikang K. Wang
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
- University of Washington, Department of Ophthalmology, Seattle, Washington, United States
| | - Matthew O’Donnell
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
- Address all correspondence to: Matthew O’Donnell, E-mail:
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77
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Zhou B, Sit AJ, Zhang X. Noninvasive measurement of wave speed of porcine cornea in ex vivo porcine eyes for various intraocular pressures. ULTRASONICS 2017; 81:86-92. [PMID: 28618301 PMCID: PMC5541902 DOI: 10.1016/j.ultras.2017.06.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 05/30/2017] [Accepted: 06/05/2017] [Indexed: 05/16/2023]
Abstract
The objective of this study was to extend an ultrasound surface wave elastography (USWE) technique for noninvasive measurement of ocular tissue elastic properties. In particular, we aim to establish the relationship between the wave speed of cornea and the intraocular pressure (IOP). Normal ranges of IOP are between 12 and 22mmHg. Ex vivo porcine eye balls were used in this research. The porcine eye ball was supported by the gelatin phantom in a testing container. Some water was pour into the container for the ultrasound measurement. A local harmonic vibration was generated on the side of the eye ball. An ultrasound probe was used to measure the wave propagation in the cornea noninvasively. A 25 gauge butterfly needle was inserted into the vitreous humor of the eye ball under the ultrasound imaging guidance. The needle was connected to a syringe. The IOP was obtained by the water height difference between the water level in the syringe and the water level in the testing container. The IOP was adjusted between 5mmHg and 30mmHg with a 5mmHg interval. The wave speed was measured at each IOP for three frequencies of 100, 150 and 200Hz. Finite element method (FEM) was used to simulate the wave propagation in the corneal according to our experimental setup. A linear viscoelastic FEM model was used to compare the experimental data. Both the experiments and the FEM analyses showed that the wave speed of cornea increased with IOP.
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Affiliation(s)
- Boran Zhou
- Department of Radiology, Mayo Clinic, USA
| | | | - Xiaoming Zhang
- Department of Radiology, Mayo Clinic, USA; Department of Biomedical Engineering and Physiology, Mayo Clinic, USA.
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78
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Lan G, Singh M, Larin KV, Twa MD. Common-path phase-sensitive optical coherence tomography provides enhanced phase stability and detection sensitivity for dynamic elastography. BIOMEDICAL OPTICS EXPRESS 2017; 8:5253-5266. [PMID: 29188118 PMCID: PMC5695968 DOI: 10.1364/boe.8.005253] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 10/16/2017] [Accepted: 10/23/2017] [Indexed: 05/08/2023]
Abstract
Phase-sensitive optical coherence elastography (PhS-OCE) is an emerging optical technique to quantify soft-tissue biomechanical properties. We implemented a common-path OCT design to enhance displacement sensitivity and optical phase stability for dynamic elastography imaging. The background phase stability was greater in common-path PhS-OCE (0.24 ± 0.07nm) than conventional PhS-OCE (1.60 ± 0.11μm). The coefficient of variation for surface displacement measurements using conventional PhS-OCE averaged 11% versus 2% for common-path PhS-OCE. Young's modulus estimates showed good precision (95% CIs) for tissue phantoms: 24.96 ± 2.18kPa (1% agar), 49.69 ± 4.87kPa (1.5% agar), and 116.08 ± 12.14kPa (2% agar), respectively. Common-path PhS-OCE effectively reduced the amplitude of background dynamic optical phase instability to a sub-nanometer level, which provided a larger dynamic detection range and higher detection sensitivity for surface displacement measurements than conventional PhS-OCE.
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Affiliation(s)
- Gongpu Lan
- School of Optometry, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Manmohan Singh
- Biomedical Engineering, University of Houston, Houston, TX, USA
| | - Kirill V. Larin
- Biomedical Engineering, University of Houston, Houston, TX, USA
- Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, Russia
| | - Michael D. Twa
- School of Optometry, University of Alabama at Birmingham, Birmingham, AL, USA
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79
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Ocular fundus pulsations within the posterior rat eye: Chorioscleral motion and response to elevated intraocular pressure. Sci Rep 2017; 7:8780. [PMID: 28821834 PMCID: PMC5562765 DOI: 10.1038/s41598-017-09310-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 07/25/2017] [Indexed: 12/13/2022] Open
Abstract
A multi-functional optical coherence tomography (OCT) approach is presented to determine ocular fundus pulsations as an axial displacement between the retina and the chorioscleral complex in the albino rat eye. By combining optical coherence elastography and OCT angiography (OCTA), we measure subtle deformations in the nanometer range within the eye and simultaneously map retinal and choroidal perfusion. The conventional OCT reflectivity contrast serves as a backbone to segment the retina and to define several slabs which are subsequently used for quantitative ocular pulsation measurements as well as for a qualitative exploration of the multi-functional OCT image data. The proposed concept is applied in healthy albino rats as well as in rats under acute elevation of the intraocular pressure (IOP). The evaluation of this experiment revealed an increased pulsatility and deformation between the retinal and chorioscleral complex while increasing the IOP level from 15 mmHg to 65 mmHg. At IOP levels exceeding 65 mmHg, the pulsatility decreased significantly and retinal as well as choroidal perfusion vanished in OCTA. Furthermore, the evaluation of the multi-parametric experiment revealed a spatial correlation between fundus pulsatility and choroidal blood flow. This indicates that the assessed pulsatility may be a valuable parameter describing the choroidal perfusion.
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80
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Qu Y, Ma T, He Y, Yu M, Zhu J, Miao Y, Dai C, Patel P, Shung KK, Zhou Q, Chen Z. Miniature probe for mapping mechanical properties of vascular lesions using acoustic radiation force optical coherence elastography. Sci Rep 2017; 7:4731. [PMID: 28680156 PMCID: PMC5498569 DOI: 10.1038/s41598-017-05077-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 05/24/2017] [Indexed: 12/15/2022] Open
Abstract
Cardiovascular diseases are the leading cause of fatalities in the United States. Atherosclerotic plaques are one of the primary complications that can lead to strokes and heart attacks if left untreated. It is essential to diagnose the disease early and distinguish vulnerable plaques from harmless ones. Many methods focus on the structural or molecular properties of plaques. Mechanical properties have been shown to change drastically when abnormalities develop in arterial tissue. We report the development of an acoustic radiation force optical coherence elastography (ARF-OCE) system that uses an integrated miniature ultrasound and optical coherence tomography (OCT) probe to map the relative elasticity of vascular tissues. We demonstrate the capability of the miniature probe to map the biomechanical properties in phantom and human cadaver carotid arteries.
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Affiliation(s)
- Yueqiao Qu
- Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Rd., Irvine, CA, 92617, USA.,Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, 92697-2700, USA
| | - Teng Ma
- NIH Ultrasonic Transducer Resource Center, University of Southern California, Los Angeles, CA, 90089, USA
| | - Youmin He
- Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Rd., Irvine, CA, 92617, USA.,Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, 92697-2700, USA
| | - Mingyue Yu
- NIH Ultrasonic Transducer Resource Center, University of Southern California, Los Angeles, CA, 90089, USA
| | - Jiang Zhu
- Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Rd., Irvine, CA, 92617, USA
| | - Yusi Miao
- Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Rd., Irvine, CA, 92617, USA.,Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, 92697-2700, USA
| | - Cuixia Dai
- Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Rd., Irvine, CA, 92617, USA.,Shanghai Institute of Technology, 100 Haiquan Road, Fengxian, Shanghai, China
| | - Pranav Patel
- Division of Cardiology, Irvine Medical Center, University of California, Orange, CA, 92868, USA
| | - K Kirk Shung
- NIH Ultrasonic Transducer Resource Center, University of Southern California, Los Angeles, CA, 90089, USA
| | - Qifa Zhou
- NIH Ultrasonic Transducer Resource Center, University of Southern California, Los Angeles, CA, 90089, USA.
| | - Zhongping Chen
- Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Rd., Irvine, CA, 92617, USA. .,Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, 92697-2700, USA.
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81
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Singh M, Li J, Han Z, Wu C, Aglyamov SR, Twa MD, Larin KV. Investigating Elastic Anisotropy of the Porcine Cornea as a Function of Intraocular Pressure With Optical Coherence Elastography. J Refract Surg 2017; 32:562-7. [PMID: 27505317 DOI: 10.3928/1081597x-20160520-01] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 04/12/2016] [Indexed: 01/02/2023]
Abstract
PURPOSE To evaluate the elastic anisotropy of porcine corneas at different intraocular pressures (IOPs) using a noncontact optical coherence elastography (OCE) technique. METHODS A focused air-pulse induced low amplitude (≤ 10 µm) elastic waves in fresh porcine corneas (n = 7) in situ in the whole eye globe configuration. A home-built phase-stabilized swept source optical coherence elastography (PhS-SSOCE) system imaged the elastic wave propagation at different stepped radial directions. A closed-loop feedback system was used to artificially control the IOP and the OCE measurements were repeated as the IOP was incrementally increased from 15 to 30 mm Hg in 5-mm Hg increments. RESULTS The OCE measurements demonstrated that the stiffness of the cornea increased as a function of IOP and elastic anisotropy of the cornea became more pronounced at higher IOPs. The standard deviation of the modified planar anisotropy coefficient increased from 0.72 ± 0.42 at an IOP of 15 mm Hg to 1.58 ± 0.40 at 30 mm Hg. CONCLUSIONS The presented noncontact OCE method was capable of detecting and assessing the corneal elastic anisotropy as a function of IOP. Due to the noninvasive nature and small amplitude of the elastic wave, this method may be able to provide further information about corneal health and integrity in vivo. [J Refract Surg. 2016;32(8):562-567.].
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82
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Singh M, Li J, Han Z, Vantipalli S, Liu CH, Wu C, Raghunathan R, Aglyamov SR, Twa MD, Larin KV. Evaluating the Effects of Riboflavin/UV-A and Rose-Bengal/Green Light Cross-Linking of the Rabbit Cornea by Noncontact Optical Coherence Elastography. Invest Ophthalmol Vis Sci 2017; 57:OCT112-20. [PMID: 27409461 PMCID: PMC4968774 DOI: 10.1167/iovs.15-18888] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Purpose The purpose of this study was to use noncontact optical coherence elastography (OCE) to evaluate and compare changes in biomechanical properties that occurred in rabbit cornea in situ after corneal collagen cross-linking by either of two techniques: ultraviolet-A (UV-A)/riboflavin or rose-Bengal/green light. Methods Low-amplitude (≤10 μm) elastic waves were induced in mature rabbit corneas by a focused air pulse. Elastic wave propagation was imaged by a phase-stabilized swept source OCE (PhS-SSOCE) system. Corneas were then cross-linked by either of two methods: UV-A/riboflavin (UV-CXL) or rose-Bengal/green light (RGX). Phase velocities of the elastic waves were fitted to a previously developed modified Rayleigh-Lamb frequency equation to obtain the viscoelasticity of the corneas before and after the cross-linking treatments. Micro-scale depth-resolved phase velocity distribution revealed the depth-wise heterogeneity of both cross-linking techniques. Results Under standard treatment settings, UV-CXL significantly increased the stiffness of the corneas by ∼47% (P < 0.05), but RGX did not produce statistically significant increases. The shear viscosities were unaffected by either cross-linking technique. The depth-wise phase velocities showed that UV-CXL affected the anterior ∼34% of the corneas, whereas RGX affected only the anterior ∼16% of the corneas. Conclusions UV-CXL significantly strengthens the cornea, whereas RGX does not, and the effects of cross-linking by UV-CXL reach deeper into the cornea than cross-linking effects of RGX under similar conditions.
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Affiliation(s)
- Manmohan Singh
- Department of Biomedical Engineering, University of Houston, Houston, Texas, United States
| | - Jiasong Li
- Department of Biomedical Engineering, University of Houston, Houston, Texas, United States
| | - Zhaolong Han
- Department of Biomedical Engineering, University of Houston, Houston, Texas, United States
| | | | - Chih-Hao Liu
- Department of Biomedical Engineering, University of Houston, Houston, Texas, United States
| | - Chen Wu
- Department of Biomedical Engineering, University of Houston, Houston, Texas, United States
| | - Raksha Raghunathan
- Department of Biomedical Engineering, University of Houston, Houston, Texas, United States
| | - Salavat R Aglyamov
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas, United States
| | - Michael D Twa
- School of Optometry, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Kirill V Larin
- Department of Biomedical Engineering, University of Houston, Houston, Texas, United States 5Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, Russia
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83
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Zhu J, Miao Y, Qi L, Qu Y, He Y, Yang Q, Chen Z. Longitudinal shear wave imaging for elasticity mapping using optical coherence elastography. APPLIED PHYSICS LETTERS 2017; 110:201101. [PMID: 28611483 PMCID: PMC5432373 DOI: 10.1063/1.4983292] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 03/28/2017] [Indexed: 05/18/2023]
Abstract
Shear wave measurements for the determination of tissue elastic properties have been used in clinical diagnosis and soft tissue assessment. A shear wave propagates as a transverse wave where vibration is perpendicular to the wave propagation direction. Previous transverse shear wave measurements could detect the shear modulus in the lateral region of the force; however, they could not provide the elastic information in the axial region of the force. In this study, we report the imaging and quantification of longitudinal shear wave propagation using optical coherence tomography to measure the elastic properties along the force direction. The experimental validation and finite element simulations show that the longitudinal shear wave propagates along the vibration direction as a plane wave in the near field of a planar source. The wave velocity measurement can quantify the shear moduli in a homogeneous phantom and a side-by-side phantom. Combining the transverse shear wave and longitudinal shear wave measurements, this system has great potential to detect the directionally dependent elastic properties in tissues without a change in the force direction.
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Affiliation(s)
- Jiang Zhu
- Beckman Laser Institute, University of California, Irvine, Irvine, California 92612, USA
| | | | - Li Qi
- Beckman Laser Institute, University of California, Irvine, Irvine, California 92612, USA
| | | | | | - Qiang Yang
- Beckman Laser Institute, University of California, Irvine, Irvine, California 92612, USA
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84
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Chin L, Latham B, Saunders CM, Sampson DD, Kennedy BF. Simplifying the assessment of human breast cancer by mapping a micro-scale heterogeneity index in optical coherence elastography. JOURNAL OF BIOPHOTONICS 2017; 10:690-700. [PMID: 27618159 DOI: 10.1002/jbio.201600092] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 07/08/2016] [Accepted: 08/13/2016] [Indexed: 05/02/2023]
Abstract
Surgical treatment of breast cancer aims to identify and remove all malignant tissue. Intraoperative assessment of tumor margins is, however, not exact; thus, re-excision is frequently needed, or excess normal tissue is removed. Imaging methods applicable intraoperatively could help to reduce re-excision rates whilst minimizing removal of excess healthy tissue. Optical coherence elastography (OCE) has been proposed for use in breast-conserving surgery; however, intraoperative interpretation of complex OCE images may prove challenging. Observations of breast cancer on multiple length scales, by OCE, ultrasound elastography, and atomic force microscopy, have shown an increase in the mechanical heterogeneity of malignant breast tumors compared to normal breast tissue. In this study, a micro-scale mechanical heterogeneity index is introduced and used to form heterogeneity maps from OCE scans of 10 ex vivo human breast tissue samples. Through comparison of OCE, optical coherence tomography images, and corresponding histology, malignant tissue is shown to possess a higher heterogeneity index than benign tissue. The heterogeneity map simplifies the contrast between tumor and normal stroma in breast tissue, facilitating the rapid identification of possible areas of malignancy, which is an important step towards intraoperative margin assessment using OCE.
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Affiliation(s)
- Lixin Chin
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, 6 Verdun St, Nedlands, Perth, WA 6009, Australia
| | - Bruce Latham
- PathWest, Fiona Stanley Hospital, Robin Warren Drive, Murdoch, WA 6150, Australia
| | - Christobel M Saunders
- School of Surgery, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
- Breast Clinic, Royal Perth Hospital, 197 Wellington Street, Perth, WA 6000, Australia
| | - David D Sampson
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
- Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
| | - Brendan F Kennedy
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, 6 Verdun St, Nedlands, Perth, WA 6009, Australia
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85
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Es’haghian S, Kennedy KM, Gong P, Li Q, Chin L, Wijesinghe P, Sampson DD, McLaughlin RA, Kennedy BF. In vivo volumetric quantitative micro-elastography of human skin. BIOMEDICAL OPTICS EXPRESS 2017; 8:2458-2471. [PMID: 28663884 PMCID: PMC5480491 DOI: 10.1364/boe.8.002458] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 03/23/2017] [Accepted: 03/24/2017] [Indexed: 05/17/2023]
Abstract
In this paper, we demonstrate in vivo volumetric quantitative micro-elastography of human skin. Elasticity is estimated at each point in the captured volume by combining local axial strain measured in the skin with local axial stress estimated at the skin surface. This is achieved by utilizing phase-sensitive detection to measure axial displacements resulting from compressive loading of the skin and an overlying, compliant, transparent layer with known stress/strain behavior. We use an imaging probe head that provides optical coherence tomography imaging and compression from the same direction. We demonstrate our technique on a tissue phantom containing a rigid inclusion, and present in vivo elastograms acquired from locations on the hand, wrist, forearm and leg of human volunteers.
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Affiliation(s)
- Shaghayegh Es’haghian
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
| | - Kelsey M. Kennedy
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, 6 Verdun Street, Nedlands, WA 6009, Australia
| | - Peijun Gong
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
| | - Qingyun Li
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
| | - Lixin Chin
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, 6 Verdun Street, Nedlands, WA 6009, Australia
- School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
| | - Philip Wijesinghe
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, 6 Verdun Street, Nedlands, WA 6009, Australia
| | - David D. Sampson
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
- Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
| | - Robert A. McLaughlin
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
- Australian Research Council Centre of Excellence for Nanoscale Biophotonics, School of Medicine, Faculty of Health Sciences, University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Brendan F. Kennedy
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, 6 Verdun Street, Nedlands, WA 6009, Australia
- School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
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86
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Fang Q, Frewer L, Wijesinghe P, Allen WM, Chin L, Hamzah J, Sampson DD, Curatolo A, Kennedy BF. Depth-encoded optical coherence elastography for simultaneous volumetric imaging of two tissue faces. OPTICS LETTERS 2017; 42:1233-1236. [PMID: 28362737 DOI: 10.1364/ol.42.001233] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Depth-encoded optical coherence elastography (OCE) enables simultaneous acquisition of two three-dimensional (3D) elastograms from opposite sides of a sample. By the choice of suitable path-length differences in each of two interferometers, the detected carrier frequencies are separated, allowing depth-ranging from each interferometer to be performed simultaneously using a single spectrometer. We demonstrate depth-encoded OCE on a silicone phantom and a freshly excised sample of mouse liver. This technique minimizes the required spectral detection hardware and halves the total scan time. Depth-encoded OCE may expedite clinical translation in time-sensitive applications requiring rapid 3D imaging of multiple tissue surfaces, such as tumor margin assessment in breast-conserving surgery.
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87
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Wijesinghe P, Sampson DD, Kennedy BF. Computational optical palpation: a finite-element approach to micro-scale tactile imaging using a compliant sensor. J R Soc Interface 2017; 14:20160878. [PMID: 28250098 PMCID: PMC5378127 DOI: 10.1098/rsif.2016.0878] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 02/02/2017] [Indexed: 12/11/2022] Open
Abstract
High-resolution tactile imaging, superior to the sense of touch, has potential for future biomedical applications such as robotic surgery. In this paper, we propose a tactile imaging method, termed computational optical palpation, based on measuring the change in thickness of a thin, compliant layer with optical coherence tomography and calculating tactile stress using finite-element analysis. We demonstrate our method on test targets and on freshly excised human breast fibroadenoma, demonstrating a resolution of up to 15-25 µm and a field of view of up to 7 mm. Our method is open source and readily adaptable to other imaging modalities, such as ultrasonography and confocal microscopy.
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Affiliation(s)
- Philip Wijesinghe
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia 6009, Australia
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, 6 Verdun Street, Nedlands, Western Australia 6009, Australia
| | - David D Sampson
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia 6009, Australia
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia 6009, Australia
| | - Brendan F Kennedy
- School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia 6009, Australia
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, 6 Verdun Street, Nedlands, Western Australia 6009, Australia
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88
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Zvietcovich F, Rolland JP, Yao J, Meemon P, Parker KJ. Comparative study of shear wave-based elastography techniques in optical coherence tomography. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:35010. [PMID: 28358943 DOI: 10.1117/1.jbo.22.3.035010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 03/15/2017] [Indexed: 05/03/2023]
Abstract
We compare five optical coherence elastography techniques able to estimate the shear speed of waves generated by one and two sources of excitation. The first two techniques make use of one piezoelectric actuator in order to produce a continuous shear wave propagation or a tone-burst propagation (TBP) of 400 Hz over a gelatin tissue-mimicking phantom. The remaining techniques utilize a second actuator located on the opposite side of the region of interest in order to create three types of interference patterns: crawling waves, swept crawling waves, and standing waves, depending on the selection of the frequency difference between the two actuators. We evaluated accuracy, contrast to noise ratio, resolution, and acquisition time for each technique during experiments. Numerical simulations were also performed in order to support the experimental findings. Results suggest that in the presence of strong internal reflections, single source methods are more accurate and less variable when compared to the two-actuator methods. In particular, TBP reports the best performance with an accuracy error < 4.1 % . Finally, the TBP was tested in a fresh chicken tibialis anterior muscle with a localized thermally ablated lesion in order to evaluate its performance in biological tissue.
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Affiliation(s)
- Fernando Zvietcovich
- University of Rochester, Department of Electrical and Computer Engineering, Rochester, New York, United States
| | - Jannick P Rolland
- University of Rochester, The Institute of Optics, Rochester, New York, United States
| | - Jianing Yao
- University of Rochester, The Institute of Optics, Rochester, New York, United States
| | - Panomsak Meemon
- University of Rochester, The Institute of Optics, Rochester, New York, United StatescSuranaree University of Technology, School of Physics, Institute of Science, Nakhon Ratchasima, Thailand
| | - Kevin J Parker
- University of Rochester, Department of Electrical and Computer Engineering, Rochester, New York, United States
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89
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Larin KV, Sampson DD. Optical coherence elastography - OCT at work in tissue biomechanics [Invited]. BIOMEDICAL OPTICS EXPRESS 2017; 8:1172-1202. [PMID: 28271011 PMCID: PMC5330567 DOI: 10.1364/boe.8.001172] [Citation(s) in RCA: 217] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 01/18/2017] [Accepted: 01/19/2017] [Indexed: 05/18/2023]
Abstract
Optical coherence elastography (OCE), as the use of OCT to perform elastography has come to be known, began in 1998, around ten years after the rest of the field of elastography - the use of imaging to deduce mechanical properties of tissues. After a slow start, the maturation of OCT technology in the early to mid 2000s has underpinned a recent acceleration in the field. With more than 20 papers published in 2015, and more than 25 in 2016, OCE is growing fast, but still small compared to the companion fields of cell mechanics research methods, and medical elastography. In this review, we describe the early developments in OCE, and the factors that led to the current acceleration. Much of our attention is on the key recent advances, with a strong emphasis on future prospects, which are exceptionally bright.
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Affiliation(s)
- Kirill V Larin
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Blvd., Houston, Texas 77204-5060, USA; Department of Molecular Physiology and Biophysics, Baylor College of Medicine, 1 Baylor Plaza, Houston, Texas 77030, USA;
| | - David D Sampson
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia; Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia;
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90
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Singh M, Li J, Han Z, Raghunathan R, Nair A, Wu C, Liu CH, Aglyamov S, Twa MD, Larin KV. Assessing the effects of riboflavin/UV-A crosslinking on porcine corneal mechanical anisotropy with optical coherence elastography. BIOMEDICAL OPTICS EXPRESS 2017; 8:349-366. [PMID: 28101423 PMCID: PMC5231304 DOI: 10.1364/boe.8.000349] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 12/10/2016] [Accepted: 12/13/2016] [Indexed: 05/02/2023]
Abstract
In this work we utilize optical coherence elastography (OCE) to assess the effects of UV-A/riboflavin corneal collagen crosslinking (CXL) on the mechanical anisotropy of in situ porcine corneas at various intraocular pressures (IOP). There was a distinct meridian of increased Young's modulus in all samples, and the mechanical anisotropy increased as a function of IOP and also after CXL. The presented noncontact OCE technique was able to quantify the Young's modulus and elastic anisotropy of the cornea and their changes as a function of IOP and CXL, opening new avenues of research for evaluating the effects of CXL on corneal biomechanical properties.
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Affiliation(s)
- Manmohan Singh
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
- Contributed equally to the present work
| | - Jiasong Li
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
- Contributed equally to the present work
| | - Zhaolong Han
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
| | - Raksha Raghunathan
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
| | - Achuth Nair
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
| | - Chen Wu
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
| | - Chih-Hao Liu
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
| | - Salavat Aglyamov
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX 78712, USA
| | - Michael D. Twa
- School of Optometry, University of Alabama at Birmingham, Birmingham, AL 35233, USA
- Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Kirill V. Larin
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, USA
- Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, Russia
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030 USA
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91
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Ambroziński Ł, Song S, Yoon SJ, Pelivanov I, Li D, Gao L, Shen TT, Wang RK, O'Donnell M. Acoustic micro-tapping for non-contact 4D imaging of tissue elasticity. Sci Rep 2016; 6:38967. [PMID: 28008920 PMCID: PMC5180181 DOI: 10.1038/srep38967] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 11/15/2016] [Indexed: 01/22/2023] Open
Abstract
Elastography plays a key role in characterizing soft media such as biological tissue. Although this technology has found widespread use in both clinical diagnostics and basic science research, nearly all methods require direct physical contact with the object of interest and can even be invasive. For a number of applications, such as diagnostic measurements on the anterior segment of the eye, physical contact is not desired and may even be prohibited. Here we present a fundamentally new approach to dynamic elastography using non-contact mechanical stimulation of soft media with precise spatial and temporal shaping. We call it acoustic micro-tapping (AμT) because it employs focused, air-coupled ultrasound to induce significant mechanical displacement at the boundary of a soft material using reflection-based radiation force. Combining it with high-speed, four-dimensional (three space dimensions plus time) phase-sensitive optical coherence tomography creates a non-contact tool for high-resolution and quantitative dynamic elastography of soft tissue at near real-time imaging rates. The overall approach is demonstrated in ex-vivo porcine cornea.
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Affiliation(s)
- Łukasz Ambroziński
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA.,AGH University of Science and Technology, Krakow, Poland
| | - Shaozhen Song
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Soon Joon Yoon
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Ivan Pelivanov
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA.,Faculty of Physics, Moscow State University, Moscow, 119991, Russia
| | - David Li
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA.,Department of Chemical Engineering, University of Washington, Seattle, WA 98195, USA
| | - Liang Gao
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Tueng T Shen
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA.,Department of Ophthalmology, University of Washington, Seattle, WA 98104, USA
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA.,Department of Ophthalmology, University of Washington, Seattle, WA 98104, USA
| | - Matthew O'Donnell
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
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92
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Han Z, Li J, Singh M, Wu C, Liu CH, Raghunathan R, Aglyamov SR, Vantipalli S, Twa MD, Larin KV. Optical coherence elastography assessment of corneal viscoelasticity with a modified Rayleigh-Lamb wave model. J Mech Behav Biomed Mater 2016; 66:87-94. [PMID: 27838594 DOI: 10.1016/j.jmbbm.2016.11.004] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 10/27/2016] [Accepted: 11/02/2016] [Indexed: 01/22/2023]
Abstract
The biomechanical properties of the cornea play a critical role in forming vision. Diseases such as keratoconus can structurally degenerate the cornea causing a pathological loss in visual acuity. UV-A/riboflavin corneal collagen crosslinking (CXL) is a clinically available treatment to stiffen the cornea and restore its healthy shape and function. However, current CXL techniques do not account for pre-existing biomechanical properties of the cornea nor the effects of the CXL treatment itself. In addition to the inherent corneal structure, the intraocular pressure (IOP) can also dramatically affect the measured biomechanical properties of the cornea. In this work, we present the details and development of a modified Rayleigh-Lamb frequency equation model for quantifying corneal biomechanical properties. After comparison with finite element modeling, the model was utilized to quantify the viscoelasticity of in situ porcine corneas in the whole eye-globe configuration before and after CXL based on noncontact optical coherence elastography measurements. Moreover, the viscoelasticity of the untreated and CXL-treated eyes was quantified at various IOPs. The results showed that the stiffness of the cornea increased after CXL and that corneal stiffness is close to linear as a function of IOP. These results show that the modified Rayleigh-Lamb wave model can provide an accurate assessment of corneal viscoelasticity, which could be used for customized CXL therapies.
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Affiliation(s)
- Zhaolong Han
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, United States
| | - Jiasong Li
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, United States
| | - Manmohan Singh
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, United States
| | - Chen Wu
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, United States
| | - Chih-Hao Liu
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, United States
| | - Raksha Raghunathan
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, United States
| | - Salavat R Aglyamov
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX 78712, United States
| | - Srilatha Vantipalli
- College of Optometry, University of Houston, Houston, TX 77204, United States
| | - Michael D Twa
- School of Optometry, University of Alabama at Birmingham, Birmingham, AL 35233, United States
| | - Kirill V Larin
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204, United States; Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, Russia; Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, United States.
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93
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Hsieh BY, Song S, Nguyen TM, Yoon SJ, Shen TT, Wang RK, O’Donnell M. Moving-source elastic wave reconstruction for high-resolution optical coherence elastography. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:116006. [PMID: 27822580 PMCID: PMC5995137 DOI: 10.1117/1.jbo.21.11.116006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 10/18/2016] [Indexed: 05/03/2023]
Abstract
Optical coherence tomography (OCT)-based elasticity imaging can map soft tissue elasticity based on speckle-tracking of elastic wave propagation using highly sensitive phase measurements of OCT signals. Using a fixed elastic wave source and moving detection, current imaging sequences have difficulty in reconstructing tissue elasticity within speckle-free regions, for example, within the crystalline lens of the eye. We present a moving acoustic radiation force imaging sequence to reconstruct elastic properties within a speckle-free region by tracking elastic wave propagation from multiple laterally moving sources across the field of view. We demonstrate the proposed strategy using heterogeneous and partial speckle-free tissue-mimicking phantoms. Harder inclusions within the speckle-free region can be detected, and the contrast-to-noise ratio slightly enhanced compared to current OCE imaging sequences. The results suggest that a moving source approach may be appropriate for OCE studies within the large speckle-free regions of the crystalline lens.
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Affiliation(s)
- Bao-Yu Hsieh
- University of Washington, Department of Bioengineering, 3720 15th Avenue NE, P. O. Box 355013, Seattle, Washington 98105, United States
- China Medical University, Department of Biomedical Imaging and Radiological Science, 91 Hsueh-Shih Road, Taichung 40402, Taiwan
- Address all correspondence to: Bao-Yu Hsieh, E-mail:
| | - Shaozhen Song
- University of Washington, Department of Bioengineering, 3720 15th Avenue NE, P. O. Box 355013, Seattle, Washington 98105, United States
| | - Thu-Mai Nguyen
- University of Washington, Department of Bioengineering, 3720 15th Avenue NE, P. O. Box 355013, Seattle, Washington 98105, United States
| | - Soon Joon Yoon
- University of Washington, Department of Bioengineering, 3720 15th Avenue NE, P. O. Box 355013, Seattle, Washington 98105, United States
| | - Tueng T. Shen
- University of Washington, Department of Bioengineering, 3720 15th Avenue NE, P. O. Box 355013, Seattle, Washington 98105, United States
- University of Washington, Department of Ophthalmology, 325 9th Avenue, Seattle, Washington 98104, United States
| | - Ruikang K. Wang
- University of Washington, Department of Bioengineering, 3720 15th Avenue NE, P. O. Box 355013, Seattle, Washington 98105, United States
- University of Washington, Department of Ophthalmology, 325 9th Avenue, Seattle, Washington 98104, United States
| | - Matthew O’Donnell
- University of Washington, Department of Bioengineering, 3720 15th Avenue NE, P. O. Box 355013, Seattle, Washington 98105, United States
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94
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3D mapping of elastic modulus using shear wave optical micro-elastography. Sci Rep 2016; 6:35499. [PMID: 27762276 PMCID: PMC5071855 DOI: 10.1038/srep35499] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 09/30/2016] [Indexed: 12/31/2022] Open
Abstract
Elastography provides a powerful tool for histopathological identification and clinical diagnosis based on information from tissue stiffness. Benefiting from high resolution, three-dimensional (3D), and noninvasive optical coherence tomography (OCT), optical micro-elastography has the ability to determine elastic properties with a resolution of ~10 μm in a 3D specimen. The shear wave velocity measurement can be used to quantify the elastic modulus. However, in current methods, shear waves are measured near the surface with an interference of surface waves. In this study, we developed acoustic radiation force (ARF) orthogonal excitation optical coherence elastography (ARFOE-OCE) to visualize shear waves in 3D. This method uses acoustic force perpendicular to the OCT beam to excite shear waves in internal specimens and uses Doppler variance method to visualize shear wave propagation in 3D. The measured propagation of shear waves agrees well with the simulation results obtained from finite element analysis (FEA). Orthogonal acoustic excitation allows this method to measure the shear modulus in a deeper specimen which extends the elasticity measurement range beyond the OCT imaging depth. The results show that the ARFOE-OCE system has the ability to noninvasively determine the 3D elastic map.
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95
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Wu C, Singh M, Han Z, Raghunathan R, Liu CH, Li J, Schill A, Larin KV. Lorentz force optical coherence elastography. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:90502. [PMID: 27622242 PMCID: PMC5018684 DOI: 10.1117/1.jbo.21.9.090502] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Accepted: 08/16/2016] [Indexed: 05/21/2023]
Abstract
Quantifying tissue biomechanical properties can assist in detection of abnormalities and monitoring disease progression and/or response to a therapy. Optical coherence elastography (OCE) has emerged as a promising technique for noninvasively characterizing tissue biomechanical properties. Several mechanical loading techniques have been proposed to induce static or transient deformations in tissues, but each has its own areas of applications and limitations. This study demonstrates the combination of Lorentz force excitation and phase-sensitive OCE at ?1.5??million A-lines per second to quantify the elasticity of tissue by directly imaging Lorentz force-induced elastic waves. This method of tissue excitation opens the possibility of a wide range of investigations using tissue biocurrents and conductivity for biomechanical analysis.
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Affiliation(s)
- Chen Wu
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Manmohan Singh
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Zhaolong Han
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Raksha Raghunathan
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Chih-Hao Liu
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Jiasong Li
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Alexander Schill
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Kirill V. Larin
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
- Tomsk State University, Interdisciplinary Laboratory of Biophotonics, 36 Lenin Avenue, Tomsk 634050, Russia
- Baylor College of Medicine, Molecular Physiology and Biophysics, One Baylor Plaza, Houston, Texas 77030, United States
- Address all correspondence to: Kirill V. Larin, E-mail:
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96
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Han Z, Singh M, Aglyamov SR, Liu CH, Nair A, Raghunathan R, Wu C, Li J, Larin KV. Quantifying tissue viscoelasticity using optical coherence elastography and the Rayleigh wave model. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:90504. [PMID: 27653931 PMCID: PMC5028422 DOI: 10.1117/1.jbo.21.9.090504] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 08/30/2016] [Indexed: 05/02/2023]
Abstract
This study demonstrates the feasibility of using the Rayleigh wave model (RWM) in combination with optical coherence elastography (OCE) technique to assess the viscoelasticity of soft tissues. Dispersion curves calculated from the spectral decomposition of OCE-measured air-pulse induced elastic waves were used to quantify the viscoelasticity of samples using the RWM. Validation studies were first conducted on 10% gelatin phantoms with different concentrations of oil. The results showed that the oil increased the viscosity of the gelatin phantom samples. This method was then used to quantify the viscoelasticity of chicken liver. The Young’s modulus of the chicken liver tissues was estimated as E=2.04±0.88??kPa with a shear viscosity ?=1.20±0.13??Pa?s. The analytical solution of the RWM correlated very well with the OCE-measured phased velocities (R2=0.96±0.04). The results show that the combination of the RWM and OCE is a promising method for noninvasively quantifying the biomechanical properties of soft tissues and may be a useful tool for detecting disease.
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Affiliation(s)
- Zhaolong Han
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Manmohan Singh
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Salavat R. Aglyamov
- University of Texas at Austin, Department of Biomedical Engineering, 107 West Dean Keeton Street, Stop C0800, Austin, Texas 78712, United States
| | - Chih-Hao Liu
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Achuth Nair
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Raksha Raghunathan
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Chen Wu
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Jiasong Li
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
| | - Kirill V. Larin
- University of Houston, Department of Biomedical Engineering, 3605 Cullen Boulevard, Houston, Texas 77204, United States
- Tomsk State University, Interdisciplinary Laboratory of Biophotonics, 36 Lenin Avenue, Tomsk 634050, Russia
- Baylor College of Medicine, Molecular Physiology and Biophysics, One Baylor Plaza, Houston, Texas 77030, United States
- Address correspondence to: Kirill V. Larin, E-mail:
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97
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Chao PY, Li PC. Three-dimensional shear wave imaging based on full-field laser speckle contrast imaging with one-dimensional mechanical scanning. OPTICS EXPRESS 2016; 24:18860-71. [PMID: 27557169 DOI: 10.1364/oe.24.018860] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The high imaging resolution and motion sensitivity of optical-based shear wave detection has made it an attractive technique in biomechanics studies with potential for improving the capabilities of shear wave elasticity imaging. In this study we implemented laser speckle contrast imaging for two-dimensional (X-Z) tracking of transient shear wave propagation in agarose phantoms. The mechanical disturbances induced by the propagation of the shear wave caused temporal and spatial fluctuations in the local speckle pattern, which manifested as local blurring. By mechanically moving the sample in the third dimension (Y), and performing two-dimensional shear wave imaging at every scan position, the three-dimensional shear wave velocity distribution of the phantom could be reconstructed. Based on comparisons with the reference shear wave velocity measurements obtained using a commercial ultrasound shear wave imaging system, the developed system can estimate the shear wave velocity with an error of less than 6% for homogeneous phantoms with shear moduli ranging from 1.52 kPa to 7.99 kPa. The imaging sensitivity of our system makes it capable of measuring small variations in shear modulus; the estimated standard deviation of the shear modulus was found to be less than 0.07 kPa. A submillimeter spatial resolution for three-dimensional shear wave imaging has been achieved, as demonstrated by the ability to detect a 1-mm-thick stiff plate embedded inside heterogeneous agarose phantoms.
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98
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Liu CH, Schill A, Wu C, Singh M, Larin KV. Non-contact single shot elastography using line field low coherence holography. BIOMEDICAL OPTICS EXPRESS 2016; 7:3021-31. [PMID: 27570694 PMCID: PMC4986810 DOI: 10.1364/boe.7.003021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 06/30/2016] [Accepted: 06/30/2016] [Indexed: 05/18/2023]
Abstract
Optical elastic wave imaging is a powerful technique that can quantify local biomechanical properties of tissues. However, typically long acquisition times make this technique unfeasible for clinical use. Here, we demonstrate non-contact single shot elastographic holography using a line-field interferometer integrated with an air-pulse delivery system. The propagation of the air-pulse induced elastic wave was imaged in real time, and required a single excitation for a line-scan measurement. Results on tissue-mimicking phantoms and chicken breast muscle demonstrated the feasibility of this technique for accurate assessment of tissue biomechanical properties with an acquisition time of a few milliseconds using parallel acquisition.
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Affiliation(s)
- Chih-Hao Liu
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas 77204, USA
| | - Alexander Schill
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas 77204, USA
| | - Chen Wu
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas 77204, USA
| | - Manmohan Singh
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas 77204, USA
| | - Kirill V. Larin
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas 77204, USA
- Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, Russia
- Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77584, USA
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99
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Liu CH, Du Y, Singh M, Wu C, Han Z, Li J, Chang A, Mohan C, Larin KV. Classifying murine glomerulonephritis using optical coherence tomography and optical coherence elastography. JOURNAL OF BIOPHOTONICS 2016; 9:781-91. [PMID: 26791097 PMCID: PMC4956579 DOI: 10.1002/jbio.201500269] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 12/06/2015] [Accepted: 12/19/2015] [Indexed: 05/18/2023]
Abstract
Acute glomerulonephritis caused by antiglomerular basement membrane marked by high mortality. The primary reason for this is delayed diagnosis via blood examination, urine analysis, tissue biopsy, or ultrasound and X-ray computed tomography imaging. Blood, urine, and tissue-based diagnoses can be time consuming, while ultrasound and CT imaging have relatively low spatial resolution, with reduced sensitivity. Optical coherence tomography is a noninvasive and high-resolution imaging technique that provides superior spatial resolution (micrometer scale) as compared to ultrasound and CT. Changes in tissue properties can be detected based on the optical metrics analyzed from the OCT signals, such as optical attenuation and speckle variance. Furthermore, OCT does not rely on ionizing radiation as with CT imaging. In addition to structural changes, the elasticity of the kidney can significantly change due to nephritis. In this work, OCT has been utilized to quantify the difference in tissue properties between healthy and nephritic murine kidneys. Although OCT imaging could identify the diseased tissue, its classification accuracy is clinically inadequate. By combining optical metrics with elasticity, the classification accuracy improves from 76% to 95%. These results show that OCT combined with OCE can be a powerful tool for identifying and classifying nephritis. Therefore, the OCT/OCE method could potentially be used as a minimally invasive tool for longitudinal studies during the progression and therapy of glomerulonephritis as well as complement and, perhaps, substitute highly invasive tissue biopsies. Elastic-wave propagation in mouse healthy and nephritic kidneys.
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Affiliation(s)
- Chih-Hao Liu
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas, 77204, USA
| | - Yong Du
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas, 77204, USA
| | - Manmohan Singh
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas, 77204, USA
| | - Chen Wu
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas, 77204, USA
| | - Zhaolong Han
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas, 77204, USA
| | - Jiasong Li
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas, 77204, USA
| | - Anthony Chang
- Department of Pathology, the University of Chicago, 5841 S. Maryland Avenue, Chicago, IL 60637, USA
| | - Chandra Mohan
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas, 77204, USA.
| | - Kirill V Larin
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Boulevard, Houston, Texas, 77204, USA.
- Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas, 77584, USA.
- Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, 634050, Russia.
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Song S, Wei W, Hsieh BY, Pelivanov I, Shen TT, O'Donnell M, Wang RK. Strategies to improve phase-stability of ultrafast swept source optical coherence tomography for single shot imaging of transient mechanical waves at 16 kHz frame rate. APPLIED PHYSICS LETTERS 2016; 108:191104. [PMID: 27375295 PMCID: PMC4866944 DOI: 10.1063/1.4949469] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 04/25/2016] [Indexed: 05/17/2023]
Abstract
We present single-shot phase-sensitive imaging of propagating mechanical waves within tissue, enabled by an ultrafast optical coherence tomography (OCT) system powered by a 1.628 MHz Fourier domain mode-locked (FDML) swept laser source. We propose a practical strategy for phase-sensitive measurement by comparing the phases between adjacent OCT B-scans, where the B-scan contains a number of A-scans equaling an integer number of FDML buffers. With this approach, we show that micro-strain fields can be mapped with ∼3.0 nm sensitivity at ∼16 000 fps. The system's capabilities are demonstrated on porcine cornea by imaging mechanical wave propagation launched by a pulsed UV laser beam, promising non-contact, real-time, and high-resolution optical coherence elastography.
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Affiliation(s)
- Shaozhen Song
- Department of Bioengineering, University of Washington , Seattle, Washington 98195, USA
| | - Wei Wei
- Department of Bioengineering, University of Washington , Seattle, Washington 98195, USA
| | - Bao-Yu Hsieh
- Department of Bioengineering, University of Washington , Seattle, Washington 98195, USA
| | - Ivan Pelivanov
- Department of Bioengineering, University of Washington , Seattle, Washington 98195, USA
| | | | - Matthew O'Donnell
- Department of Bioengineering, University of Washington , Seattle, Washington 98195, USA
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