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Chen Z, Gezginer I, Zhou Q, Tang L, Deán-Ben XL, Razansky D. Multimodal optoacoustic imaging: methods and contrast materials. Chem Soc Rev 2024; 53:6068-6099. [PMID: 38738633 PMCID: PMC11181994 DOI: 10.1039/d3cs00565h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Indexed: 05/14/2024]
Abstract
Optoacoustic (OA) imaging offers powerful capabilities for interrogating biological tissues with rich optical absorption contrast while maintaining high spatial resolution for deep tissue observations. The spectrally distinct absorption of visible and near-infrared photons by endogenous tissue chromophores facilitates extraction of diverse anatomic, functional, molecular, and metabolic information from living tissues across various scales, from organelles and cells to whole organs and organisms. The primarily blood-related contrast and limited penetration depth of OA imaging have fostered the development of multimodal approaches to fully exploit the unique advantages and complementarity of the method. We review the recent hybridization efforts, including multimodal combinations of OA with ultrasound, fluorescence, optical coherence tomography, Raman scattering microscopy and magnetic resonance imaging as well as ionizing methods, such as X-ray computed tomography, single-photon-emission computed tomography and positron emission tomography. Considering that most molecules absorb light across a broad range of the electromagnetic spectrum, the OA interrogations can be extended to a large number of exogenously administered small molecules, particulate agents, and genetically encoded labels. This unique property further makes contrast moieties used in other imaging modalities amenable for OA sensing.
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Affiliation(s)
- Zhenyue Chen
- Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Switzerland.
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Irmak Gezginer
- Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Switzerland.
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Quanyu Zhou
- Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Switzerland.
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Lin Tang
- Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Switzerland.
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Xosé Luís Deán-Ben
- Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Switzerland.
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Daniel Razansky
- Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Switzerland.
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
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2
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Ryan C, Haist T, Laskin G, Schröder S, Reichelt S. Technology Selection for Inline Topography Measurement with Rover-Borne Laser Spectrometers. SENSORS (BASEL, SWITZERLAND) 2024; 24:2872. [PMID: 38732976 PMCID: PMC11086144 DOI: 10.3390/s24092872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 04/22/2024] [Accepted: 04/25/2024] [Indexed: 05/13/2024]
Abstract
This work studies enhancing the capabilities of compact laser spectroscopes integrated into space-exploration rovers by adding 3D topography measurement techniques. Laser spectroscopy enables the in situ analysis of sample composition, aiding in the understanding of the geological history of extraterrestrial bodies. To complement spectroscopic data, the inclusion of 3D imaging is proposed to provide unprecedented contextual information. The morphological information aids material characterization and hence the constraining of rock and mineral histories. Assigning height information to lateral pixels creates topographies, which offer a more complete spatial dataset than contextual 2D imaging. To aid the integration of 3D measurement into future proposals for rover-based laser spectrometers, the relevant scientific, rover, and sample constraints are outlined. The candidate 3D technologies are discussed, and estimates of performance, weight, and power consumptions guide the down-selection process in three application examples. Technology choice is discussed from different perspectives. Inline microscopic fringe-projection profilometry, incoherent digital holography, and multiwavelength digital holography are found to be promising candidates for further development.
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Affiliation(s)
- Conor Ryan
- Institute for Applied Optics (ITO), University of Stuttgart, 70569 Stuttgart, Germany
- Institute of Optical Sensor Systems, German Aerospace Center, 12489 Berlin, Germany
| | - Tobias Haist
- Institute for Applied Optics (ITO), University of Stuttgart, 70569 Stuttgart, Germany
| | - Gennadii Laskin
- Department of Production Control, Fraunhofer Institute for Physical Measurement Techniques IPM, 79110 Freiburg, Germany
| | - Susanne Schröder
- Institute of Optical Sensor Systems, German Aerospace Center, 12489 Berlin, Germany
| | - Stephan Reichelt
- Institute for Applied Optics (ITO), University of Stuttgart, 70569 Stuttgart, Germany
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3
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Ge S, Li X, Liu Z, Zhao J, Wang W, Li S, Zhang W. Polarization-multiplexed metasurface enabled tri-functional imaging. OPTICS LETTERS 2023; 48:5683-5686. [PMID: 37910733 DOI: 10.1364/ol.502632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 10/08/2023] [Indexed: 11/03/2023]
Abstract
Diffraction-limited focusing imaging, edge-enhanced imaging, and long depth of focus imaging offer crucial technical capabilities for applications such as biological microscopy and surface topography detection. To conveniently and quickly realize the microscopy imaging of different functions, the multifunctional integrated system of microscopy imaging has become an increasingly important research direction. However, conventional microscopes necessitate bulky optical components to switch between these functionalities, suffering from the system's complexity and unstability. Hence, solving the problem of integrating multiple functions within an optical system is a pressing need. In this work, we present an approach using a polarization-multiplexed tri-functional metasurface, capable of realizing the aforementioned imaging functions simply by changing the polarization state of the input and output light, enhancing the system structure's compactness and flexibility. This work offers a new avenue for multifunctional imaging, with potential applications in biomedicine and microscopy imaging.
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4
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Asghari H. Visible wavelength time-stretch optical coherence tomography. OPTICS EXPRESS 2023; 31:24085-24096. [PMID: 37475244 DOI: 10.1364/oe.492753] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 06/21/2023] [Indexed: 07/22/2023]
Abstract
Visible light optical coherence tomography (OCT) is an emerging non-invasive imaging modality that offers new opportunities for anatomical and functional imaging of biological tissues. Time-stretch dispersive Fourier transform, also known as photonic time-stretch, is an all-optical processing method that enables real-time Fourier transformation of ultrafast optical signals and allows for OCT at high A-scan rates. In this work, a working prototype of a photonic time-stretch OCT (TS-OCT) method in the visible wavelength region is proposed and experimentally demonstrated. The proposed visible-light TS-OCT system achieves unprecedented throughput of 100 giga voxels/second and OCT volume rate of 4,000 volumes/second and can be used to expand the range of applications of TS-OCT systems.
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5
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Nelson MS, Liu Y, Wilson HM, Li B, Rosado-Mendez IM, Rogers JD, Block WF, Eliceiri KW. Multiscale Label-Free Imaging of Fibrillar Collagen in the Tumor Microenvironment. Methods Mol Biol 2023; 2614:187-235. [PMID: 36587127 DOI: 10.1007/978-1-0716-2914-7_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
With recent advances in cancer therapeutics, there is a great need for improved imaging methods for characterizing cancer onset and progression in a quantitative and actionable way. Collagen, the most abundant extracellular matrix protein in the tumor microenvironment (and the body in general), plays a multifaceted role, both hindering and promoting cancer invasion and progression. Collagen deposition can defend the tumor with immunosuppressive effects, while aligned collagen fiber structures can enable tumor cell migration, aiding invasion and metastasis. Given the complex role of collagen fiber organization and topology, imaging has been a tool of choice to characterize these changes on multiple spatial scales, from the organ and tumor scale to cellular and subcellular level. Macroscale density already aids in the detection and diagnosis of solid cancers, but progress is being made to integrate finer microscale features into the process. Here we review imaging modalities ranging from optical methods of second harmonic generation (SHG), polarized light microscopy (PLM), and optical coherence tomography (OCT) to the medical imaging approaches of ultrasound and magnetic resonance imaging (MRI). These methods have enabled scientists and clinicians to better understand the impact collagen structure has on the tumor environment, at both the bulk scale (density) and microscale (fibrillar structure) levels. We focus on imaging methods with the potential to both examine the collagen structure in as natural a state as possible and still be clinically amenable, with an emphasis on label-free strategies, exploiting intrinsic optical properties of collagen fibers.
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Affiliation(s)
- Michael S Nelson
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, WI, USA.,Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Yuming Liu
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, WI, USA
| | - Helen M Wilson
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, WI, USA.,Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Bin Li
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, WI, USA.,Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA.,Morgridge Institute for Research, Madison, WI, USA
| | - Ivan M Rosado-Mendez
- Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, USA
| | - Jeremy D Rogers
- Morgridge Institute for Research, Madison, WI, USA.,McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, USA
| | - Walter F Block
- Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, USA
| | - Kevin W Eliceiri
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, WI, USA. .,Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA. .,Morgridge Institute for Research, Madison, WI, USA. .,Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, USA. .,McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, USA.
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6
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Dey R, Alexandrov S, Owens P, Kelly J, Phelan S, Leahy M. Skin cancer margin detection using nanosensitive optical coherence tomography and a comparative study with confocal microscopy. BIOMEDICAL OPTICS EXPRESS 2022; 13:5654-5666. [PMID: 36733740 PMCID: PMC9872867 DOI: 10.1364/boe.474334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/23/2022] [Accepted: 09/26/2022] [Indexed: 05/08/2023]
Abstract
Excision biopsy and histology represent the gold standard for morphological investigation of the skin, in particular for cancer diagnostics. Nevertheless, a biopsy may alter the original morphology, usually requires several weeks for results, is non-repeatable on the same site and always requires an iatrogenic trauma. Hence, diagnosis and clinical management of diseases may be substantially improved by new non-invasive imaging techniques. Optical Coherence Tomography (OCT) is a non-invasive depth-resolved optical imaging modality based on low coherence interferometry that enables high-resolution, cross-sectional imaging in biological tissues and it can be used to obtain both structural and functional information. Beyond the resolution limit, it is not possible to detect structural and functional information using conventional OCT. In this paper, we present a recently developed technique, nanosensitive OCT (nsOCT), improved using broadband supercontinuum laser, and demonstrate nanoscale sensitivity to structural changes within ex vivo human skin tissue. The extended spectral bandwidth permitted access to a wider distribution of spatial frequencies and improved the dynamic range of the nsOCT. Firstly, we demonstrate numerical and experimental detection of a few nanometers structural difference using the nsOCT method from single B-scan images of phantoms with sub-micron periodic structures, acting like Bragg gratings, along the depth. Secondly, our study shows that nsOCT can distinguish nanoscale structural changes at the skin cancer margin from the healthy region in en face images at clinically relevant depths. Finally, we compare the nsOCT en face image with a high-resolution confocal microscopy image to confirm the structural differences between the healthy and lesional/cancerous regions, allowing the detection of the skin cancer margin.
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Affiliation(s)
- Rajib Dey
- Tissue Optics and Microcirculation Imaging (TOMI) Facility, National Biophotonics and Imaging Platform School of Physics, National University of Ireland, Galway, Galway, Ireland
| | - Sergey Alexandrov
- Tissue Optics and Microcirculation Imaging (TOMI) Facility, National Biophotonics and Imaging Platform School of Physics, National University of Ireland, Galway, Galway, Ireland
| | - Peter Owens
- Center for Microscopy and Imaging, National University of Ireland, Galway, Galway, Ireland
| | - Jack Kelly
- Plastic and Reconstructive Surgery, Galway University Hospital, Galway, Ireland
| | - Sine Phelan
- Department of Anatomic Pathology, Galway University Hospital and Department of Pathology, National University of Ireland, Galway, Galway, Ireland
| | - Martin Leahy
- Tissue Optics and Microcirculation Imaging (TOMI) Facility, National Biophotonics and Imaging Platform School of Physics, National University of Ireland, Galway, Galway, Ireland
- Institute of Photonic Sciences (ICFO), Barcelona, Spain
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7
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Fang R, Rubinoff I, Zhang HF. Multiple forward scattering reduces the measured scattering coefficient of whole blood in visible-light optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2022; 13:4510-4527. [PMID: 36187273 PMCID: PMC9484418 DOI: 10.1364/boe.459607] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 05/10/2023]
Abstract
The optical properties of blood encode oxygen-dependent information. Noninvasive optical detection of these properties is increasingly desirable to extract biomarkers for tissue health. Recently, visible-light optical coherence tomography (vis-OCT) demonstrated retinal oxygen saturation (sO2) measurements by inversely measuring the oxygen-dependent absorption and scattering coefficients of whole blood. However, vis-OCT may be sensitive to optical scattering properties of whole blood, different from those reported in the literature. Incorrect assumptions of such properties can add additional uncertainties or biases to vis-OCT's sO2 model. This work investigates whole blood's scattering coefficient measured by vis-OCT. Using Monte Carlo simulation of a retinal vessel, we determined that vis-OCT almost exclusively detects multiple-scattered photons in whole blood. Meanwhile, photons mostly forward scatter in whole blood within the visible spectral range, allowing photons to maintain ballistic paths and penetrate deeply, leading to a reduction in the measured scattering coefficient. We defined a scattering scaling factor (SSF) to account for such a reduction and found that SSF varied with measurement conditions, such as numerical aperture, depth resolution, and depth selection. We further experimentally validated SSF in ex vivo blood phantoms with pre-set sO2 levels and in the human retina, both of which agreed well with our simulation.
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Affiliation(s)
- Raymond Fang
- Department of Biomedical Engineering, Northwestern University, Evanston IL 60208, USA
- These authors contributed equally to this work
| | - Ian Rubinoff
- Department of Biomedical Engineering, Northwestern University, Evanston IL 60208, USA
- These authors contributed equally to this work
| | - Hao F. Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston IL 60208, USA
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8
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Kendall WY, Bordas J, Mirminachi S, Joseph A, Roper J, Wax A. Spectroscopic optical coherence tomography for classification of colorectal cancer in a mouse model. JOURNAL OF BIOPHOTONICS 2022; 15:e202100387. [PMID: 35338763 DOI: 10.1002/jbio.202100387] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 06/14/2023]
Abstract
Noninvasive diagnosis of the malignant potential of colon polyps can improve prevention of colorectal cancer without the need for time-consuming and expensive biopsies. This study examines the use of spectroscopic optical coherence tomography (OCT) to classify tissue from genetically engineered mouse models of early-stage adenoma (APC) and advanced adenocarcinoma (AKP) in which tumors are induced in the distal colon. The optical tissue properties of scattering power and scattering attenuation coefficient are evaluated by analyzing the imaging data collected from tissues. Classifications are generated using 2D linear discriminant analysis with high levels of discrimination obtained. The overall classification accuracy obtained was 91.5%, with 100% sensitivity and 96.7% specificity in separating tumors from benign tissue, and 77.8% sensitivity and 99.4% specificity in separating adenocarcinoma from nonmalignant tissue. Thus, this study demonstrates the clinical potential of using spectroscopic OCT for rapid detection of colon adenoma and colorectal cancer.
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Affiliation(s)
- Wesley Y Kendall
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA
| | - Julianna Bordas
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA
| | | | - Abel Joseph
- Department of Gastroenterology, Duke Medicine, Durham, North Carolina, USA
| | - Jatin Roper
- Department of Gastroenterology, Duke Medicine, Durham, North Carolina, USA
| | - Adam Wax
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA
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9
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Wang J, Song W, Sadlak N, Fiorello MG, Desai M, Yi J. A Baseline Study of Oxygen Saturation in Parafoveal Vessels Using Visible Light Optical Coherence Tomography. Front Med (Lausanne) 2022; 9:886576. [PMID: 35646980 PMCID: PMC9133487 DOI: 10.3389/fmed.2022.886576] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/20/2022] [Indexed: 01/02/2023] Open
Abstract
The retinal macula is at the center of our visual field, and thus pathological damage in the macula significantly impacts an individual's quality of life. The parafoveal vessels form the inner retina provide oxygen perfusion, and the measurement of parafoveal oxygen saturation (sO2) can evaluate macular metabolism and provide pathophysiological insight. In this paper, for the first time, we present a baseline study of microvascular oxygen saturation (sO2) in perifoveal macular region using visible light optical coherence tomography (VIS-OCT) on normal eyes. The arterial and venous sO2 from all eyes was 92.1 ± 7.1 (vol %) and 48.4 ± 5.0 (vol %) (mean ± SD), respectively. Arteriovenous sO2 difference was 43.8 ± 9.5 (vol %). Marginal correlation was found between venous sO2 and intraocular pressure (IOP) among eyes. No significant correlation was found between sO2 and vessel topological features, including length, diameter, and distance to fovea. This baseline study could serve as a benchmark for the future sO2 investigation of retinal macular pathologies.
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Affiliation(s)
- Jingyu Wang
- Department of Ophthalmology, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Weiye Song
- School of Mechanical Engineering, Shandong University, Jinan, China,Department of Ophthalmology, Boston Medical Center, Boston, MA, United States
| | - Natalie Sadlak
- Department of Ophthalmology, Boston Medical Center, Boston, MA, United States
| | - Marissa G. Fiorello
- Department of Ophthalmology, Boston Medical Center, Boston, MA, United States
| | - Manishi Desai
- Department of Ophthalmology, Boston Medical Center, Boston, MA, United States
| | - Ji Yi
- Department of Ophthalmology, School of Medicine, Johns Hopkins University, Baltimore, MD, United States,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States,*Correspondence: Ji Yi
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10
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Wang A, Qi W, Gao T, Tang X. Molecular Contrast Optical Coherence Tomography and Its Applications in Medicine. Int J Mol Sci 2022; 23:ijms23063038. [PMID: 35328454 PMCID: PMC8949853 DOI: 10.3390/ijms23063038] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 03/05/2022] [Accepted: 03/08/2022] [Indexed: 12/28/2022] Open
Abstract
The growing need to understand the molecular mechanisms of diseases has prompted the revolution in molecular imaging techniques along with nanomedicine development. Conventional optical coherence tomography (OCT) is a low-cost in vivo imaging modality that provides unique high spatial and temporal resolution anatomic images but little molecular information. However, given the widespread adoption of OCT in research and clinical practice, its robust molecular imaging extensions are strongly desired to combine with anatomical images. A range of relevant approaches has been reported already. In this article, we review the recent advances of molecular contrast OCT imaging techniques, the corresponding contrast agents, especially the nanoparticle-based ones, and their applications. We also summarize the properties, design criteria, merit, and demerit of those contrast agents. In the end, the prospects and challenges for further research and development in this field are outlined.
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11
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Portable, handheld, and affordable blood perfusion imager for screening of subsurface cancer in resource-limited settings. Proc Natl Acad Sci U S A 2022; 119:2026201119. [PMID: 34983869 PMCID: PMC8764675 DOI: 10.1073/pnas.2026201119] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2021] [Indexed: 12/11/2022] Open
Abstract
Existing procedures of screening subsurface cancers are either prohibitively resource-intensive and expensive or are unable to provide direct quantitative estimates of the relevant physiological parameters for accurate classification accommodating interpatient variabilities and overlapping clinical manifestations. Here, we introduce a handheld and inexpensive blood perfusion imager that provides a noninvasive in situ screening approach for distinguishing precancer, cancer, and normal scenarios by precise quantitative estimation of the localized blood circulation in the tissue over an unrestricted region of interest without any unwarranted noise in the data, augmented by machine learning–based classification. Clinical trials in minimally resourced settings have established the efficacy of the method in differentiating cancerous and precancerous stages of suspected oral abnormalities, as verified by gold-standard biopsy reports. Precise information on localized variations in blood circulation holds the key for noninvasive diagnostics and therapeutic assessment of various forms of cancer. While thermal imaging by itself may provide significant insights on the combined implications of the relevant physiological parameters, viz. local blood perfusion and metabolic balance due to active tumors as well as the ambient conditions, knowledge of the tissue surface temperature alone may be somewhat inadequate in distinguishing between some ambiguous manifestations of precancer and cancerous lesions, resulting in compromise of the selectivity in detection. This, along with the lack of availability of a user-friendly and inexpensive portable device for thermal-image acquisition, blood perfusion mapping, and data integration acts as a deterrent against the emergence of an inexpensive, contact-free, and accurate in situ screening and diagnostic approach for cancer detection and management. Circumventing these constraints, here we report a portable noninvasive blood perfusion imager augmented with machine learning–based quantitative analytics for screening precancerous and cancerous traits in oral lesions, by probing the localized alterations in microcirculation. With a proven overall sensitivity >96.66% and specificity of 100% as compared to gold-standard biopsy-based tests, the method successfully classified oral cancer and precancer in a resource-limited clinical setting in a double-blinded patient trial and exhibited favorable predictive capabilities considering other complementary modes of medical image analysis as well. The method holds further potential to achieve contrast-free, accurate, and low-cost diagnosis of abnormal microvascular physiology and other clinically vulnerable conditions, when interpreted along with complementary clinically evidenced decision-making perspectives.
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12
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Kho AM, Srinivasan VJ. Proactive spectrometer matching for excess noise suppression in balanced visible light optical coherence tomography (OCT). OPTICS EXPRESS 2021; 29. [PMCID: PMC8970694 DOI: 10.1364/oe.439919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Supercontinuum sources for visible light spectral domain OCT (SDOCT) are noisy and often expensive. Balanced detection can reduce excess noise, but is rarely used in SDOCT. Here, we show that balanced detection can achieve effective excess noise cancellation across all depths if two linear array spectrometers are spectrally well-matched. We propose excess noise correlation matrices as tools to achieve such precise spectral matching. Using optomechanical adjustments, while monitoring noise correlations, we proactively match wavelength sampling of two different spectrometers to just a few picometers in wavelength, or 0.001% of the overall spectral range. We show that proactively-matched spectrometers can achieve an excess noise suppression of more than two orders-of-magnitude in balanced visible light OCT, outperforming simple retrospective software calibration of mismatched spectrometers. High noise suppression enables visible light OCT of the mouse retina at 70 kHz with 125 microwatts incident power, with an inexpensive, 30 MHz repetition rate supercontinuum source. Averaged images resolve the retinal pigment epithelium in a highly pigmented mouse strain.
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Affiliation(s)
- Aaron M. Kho
- Department of Biomedical Engineering, University of California Davis, Davis, California 95616, USA
| | - Vivek J. Srinivasan
- Department of Biomedical Engineering, University of California Davis, Davis, California 95616, USA
- Department of Ophthalmology and Vision Science, University of California Davis, Davis School of Medicine, Sacramento, California 96817, USA
- Department of Ophthalmology, NYU Langone Health, New York, New York 10017, USA
- Department of Radiology, NYU Langone Health, New York, New York 10016, USA
- Tech4Health Institute, NYU Langone Health, New York, New York 10010, USA
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13
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Alexandrov S, Arangath A, Zhou Y, Murphy M, Duffy N, Neuhaus K, Shaw G, McAuley R, Leahy M. Accessing depth-resolved high spatial frequency content from the optical coherence tomography signal. Sci Rep 2021; 11:17123. [PMID: 34429483 PMCID: PMC8385072 DOI: 10.1038/s41598-021-96619-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 07/28/2021] [Indexed: 11/17/2022] Open
Abstract
Optical coherence tomography (OCT) is a rapidly evolving technology with a broad range of applications, including biomedical imaging and diagnosis. Conventional intensity-based OCT provides depth-resolved imaging with a typical resolution and sensitivity to structural alterations of about 5–10 microns. It would be desirable for functional biological imaging to detect smaller features in tissues due to the nature of pathological processes. In this article, we perform the analysis of the spatial frequency content of the OCT signal based on scattering theory. We demonstrate that the OCT signal, even at limited spectral bandwidth, contains information about high spatial frequencies present in the object which relates to the small, sub-wavelength size structures. Experimental single frame imaging of phantoms with well-known sub-micron internal structures confirms the theory. Examples of visualization of the nanoscale structural changes within mesenchymal stem cells (MSC), which are invisible using conventional OCT, are also shown. Presented results provide a theoretical and experimental basis for the extraction of high spatial frequency information to substantially improve the sensitivity of OCT to structural alterations at clinically relevant depths.
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Affiliation(s)
- Sergey Alexandrov
- National University of Ireland, National Biophotonics and Imaging Platform, School of Physics, Tissue Optics and Microcirculation Imaging Group, Galway, H91 TK33, Ireland.
| | - Anand Arangath
- National University of Ireland, National Biophotonics and Imaging Platform, School of Physics, Tissue Optics and Microcirculation Imaging Group, Galway, H91 TK33, Ireland
| | - Yi Zhou
- National University of Ireland, National Biophotonics and Imaging Platform, School of Physics, Tissue Optics and Microcirculation Imaging Group, Galway, H91 TK33, Ireland
| | - Mary Murphy
- Regenerative Medicine Institute, School of Medicine, National University of Ireland, Galway, Ireland
| | - Niamh Duffy
- Regenerative Medicine Institute, School of Medicine, National University of Ireland, Galway, Ireland
| | - Kai Neuhaus
- National University of Ireland, National Biophotonics and Imaging Platform, School of Physics, Tissue Optics and Microcirculation Imaging Group, Galway, H91 TK33, Ireland
| | - Georgina Shaw
- Regenerative Medicine Institute, School of Medicine, National University of Ireland, Galway, Ireland
| | - Ryan McAuley
- National University of Ireland, National Biophotonics and Imaging Platform, School of Physics, Tissue Optics and Microcirculation Imaging Group, Galway, H91 TK33, Ireland
| | - Martin Leahy
- National University of Ireland, National Biophotonics and Imaging Platform, School of Physics, Tissue Optics and Microcirculation Imaging Group, Galway, H91 TK33, Ireland.,Institute of Photonic Sciences (ICFO), Barcelona, Spain
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14
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Song G, Jelly ET, Chu KK, Kendall WY, Wax A. A review of low-cost and portable optical coherence tomography. PROGRESS IN BIOMEDICAL ENGINEERING (BRISTOL, ENGLAND) 2021; 3:032002. [PMID: 37645660 PMCID: PMC10465117 DOI: 10.1088/2516-1091/abfeb7] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Optical coherence tomography (OCT) is a powerful optical imaging technique capable of visualizing the internal structure of biological tissues at near cellular resolution. For years, OCT has been regarded as the standard of care in ophthalmology, acting as an invaluable tool for the assessment of retinal pathology. However, the costly nature of most current commercial OCT systems has limited its general accessibility, especially in low-resource environments. It is therefore timely to review the development of low-cost OCT systems as a route for applying this technology to population-scale disease screening. Low-cost, portable and easy to use OCT systems will be essential to facilitate widespread use at point of care settings while ensuring that they offer the necessary imaging performances needed for clinical detection of retinal pathology. The development of low-cost OCT also offers the potential to enable application in fields outside ophthalmology by lowering the barrier to entry. In this paper, we review the current development and applications of low-cost, portable and handheld OCT in both translational and research settings. Design and cost-reduction techniques are described for general low-cost OCT systems, including considerations regarding spectrometer-based detection, scanning optics, system control, signal processing, and the role of 3D printing technology. Lastly, a review of clinical applications enabled by low-cost OCT is presented, along with a detailed discussion of current limitations and outlook.
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Affiliation(s)
- Ge Song
- Author to whom any correspondence should be addressed.
| | | | - Kengyeh K Chu
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, United States of America
| | - Wesley Y Kendall
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, United States of America
| | - Adam Wax
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, United States of America
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15
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Chen X, Kandel ME, Popescu G. Spatial light interference microscopy: principle and applications to biomedicine. ADVANCES IN OPTICS AND PHOTONICS 2021; 13:353-425. [PMID: 35494404 PMCID: PMC9048520 DOI: 10.1364/aop.417837] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In this paper, we review spatial light interference microscopy (SLIM), a common-path, phase-shifting interferometer, built onto a phase-contrast microscope, with white-light illumination. As one of the most sensitive quantitative phase imaging (QPI) methods, SLIM allows for speckle-free phase reconstruction with sub-nanometer path-length stability. We first review image formation in QPI, scattering, and full-field methods. Then, we outline SLIM imaging from theory and instrumentation to diffraction tomography. Zernike's phase-contrast microscopy, phase retrieval in SLIM, and halo removal algorithms are discussed. Next, we discuss the requirements for operation, with a focus on software developed in-house for SLIM that enables high-throughput acquisition, whole slide scanning, mosaic tile registration, and imaging with a color camera. We introduce two methods for solving the inverse problem using SLIM, white-light tomography, and Wolf phase tomography. Lastly, we review the applications of SLIM in basic science and clinical studies. SLIM can study cell dynamics, cell growth and proliferation, cell migration, mass transport, etc. In clinical settings, SLIM can assist with cancer studies, reproductive technology, blood testing, etc. Finally, we review an emerging trend, where SLIM imaging in conjunction with artificial intelligence brings computational specificity and, in turn, offers new solutions to outstanding challenges in cell biology and pathology.
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16
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Optical density based quantification of total haemoglobin concentrations with spectroscopic optical coherence tomography. Sci Rep 2021; 11:8680. [PMID: 33883617 PMCID: PMC8060256 DOI: 10.1038/s41598-021-88063-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 04/05/2021] [Indexed: 11/21/2022] Open
Abstract
Spectroscopic optical coherence tomography (sOCT) has emerged as a new possibility for non-invasive quantification of total haemoglobin concentrations [tHb]. Recently, we demonstrated that [tHb] measured in ex-vivo human whole-blood with a conventional sOCT system achieves a precision of 9.10 g/dL with a bias of 1.50 g/dL. This precision improved by acquiring data with a combination of focus tracking and zero-delay acquisition (FZA) that compensated for experimental limitations, increasing to 3.80 g/dL with a bias of 1.50 g/dL. Nevertheless, sOCT precision should improve at least to \documentclass[12pt]{minimal}
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\begin{document}$$\sim 2$$\end{document}∼2 g/dL to be clinically relevant. Therefore, sOCT-based [tHb] determinations require the development of new analysis methods that reduce the variability of [tHb] estimations. In this work, we aim to increase sOCT precision by retrieving the [tHb] content from a numerical optimisation of the optical density (OD), while considering the blood absorption flattening effect. The OD-based approach simplifies previous two-step Lambert–Beer fitting approaches to a single step, thereby reducing errors during the fitting procedure. We validated our model with ex-vivo [tHb] measurements on flowing whole-blood samples in the clinical range (7–23 g/dL). Our results show that, with the new model, conventional sOCT can determine [tHb] with a precision of 3.09 g/dL and a bias of 0.86 g/dL compared to a commercial blood analyser. We present further precision improvement by combining the OD methodology with FZA, leading to a precision of 2.08 g/dL with a bias of 0.46 g/dL.
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17
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Ringel MJ, Tang EM, Tao YK. Advances in multimodal imaging in ophthalmology. Ther Adv Ophthalmol 2021; 13:25158414211002400. [PMID: 35187398 PMCID: PMC8855415 DOI: 10.1177/25158414211002400] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 02/23/2021] [Indexed: 12/12/2022] Open
Abstract
Multimodality ophthalmic imaging systems aim to enhance the contrast, resolution, and functionality of existing technologies to improve disease diagnostics and therapeutic guidance. These systems include advanced acquisition and post-processing methods using optical coherence tomography (OCT), combined scanning laser ophthalmoscopy and OCT systems, adaptive optics, surgical guidance, and photoacoustic technologies. Here, we provide an overview of these ophthalmic imaging systems and their clinical and basic science applications.
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Affiliation(s)
- Morgan J. Ringel
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Eric M. Tang
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Yuankai K. Tao
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37235, USA
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18
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Xing F, Lee JH, Polucha C, Lee J. Design and optimization of line-field optical coherence tomography at visible wavebands. BIOMEDICAL OPTICS EXPRESS 2021; 12:1351-1365. [PMID: 33796358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 01/25/2021] [Accepted: 01/29/2021] [Indexed: 06/12/2023]
Abstract
Parallel line-field Fourier-domain optical coherence tomography (LF-FDOCT) has emerged to enable relatively higher speeds than the conventional FDOCT system. In the LF-FDOCT, one B-scan is captured at a time instead of scanning the beam to acquire hundreds of A-scans. On the other hand, spectroscopic OCT using the visible waveband provides absorption information over multiple wavelengths at each voxel. This information of spectral absorption enables quantitative measurement of blood oxygenation, voxel by voxel. Here, we presented the design and optimization of a LF-FDOCT system at the visible waveband (520-620 nm), especially using a generic Camera Link area sensor (2048 × 1088 pixels). To optimize the axial resolution and depth of imaging volume, we simulated various parameters and found that two Nyquist optima can exist, the origin and implication of which has been discussed. As a result, our system acquired 1088 A-scans in parallel at the camera's frame rate of 281 frame per second, achieving an equivalent rate of over 300,000 A-scan/s, while minimizing sacrifice in the point spread function (2.8 × 3.1 × 3.2 µm3, x × y × z) and the field of view (750 × 750 × 750 µm3). As an example of application, we presented high-speed imaging of blood oxygenation in the rodent brain cortex.
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Affiliation(s)
- Fangjian Xing
- School of Computer and Electronic information, Nanjing Normal University, Nanjing, 210023, China
- Center for Biomedical Engineering, School of Engineering, Brown University, Providence, Rhode Island 02912, USA
| | - Jang-Hoon Lee
- Center for Biomedical Engineering, School of Engineering, Brown University, Providence, Rhode Island 02912, USA
| | - Collin Polucha
- Center for Biomedical Engineering, School of Engineering, Brown University, Providence, Rhode Island 02912, USA
| | - Jonghwan Lee
- Center for Biomedical Engineering, School of Engineering, Brown University, Providence, Rhode Island 02912, USA
- Carney Institute for Brain Science, Brown University, Providence, Rhode Island 02912, USA
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19
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Xing F, Lee JH, Polucha C, Lee J. Design and optimization of line-field optical coherence tomography at visible wavebands. BIOMEDICAL OPTICS EXPRESS 2021; 12:1351-1365. [PMID: 33796358 PMCID: PMC7984778 DOI: 10.1364/boe.413424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 01/25/2021] [Accepted: 01/29/2021] [Indexed: 06/17/2023]
Abstract
Parallel line-field Fourier-domain optical coherence tomography (LF-FDOCT) has emerged to enable relatively higher speeds than the conventional FDOCT system. In the LF-FDOCT, one B-scan is captured at a time instead of scanning the beam to acquire hundreds of A-scans. On the other hand, spectroscopic OCT using the visible waveband provides absorption information over multiple wavelengths at each voxel. This information of spectral absorption enables quantitative measurement of blood oxygenation, voxel by voxel. Here, we presented the design and optimization of a LF-FDOCT system at the visible waveband (520-620 nm), especially using a generic Camera Link area sensor (2048 × 1088 pixels). To optimize the axial resolution and depth of imaging volume, we simulated various parameters and found that two Nyquist optima can exist, the origin and implication of which has been discussed. As a result, our system acquired 1088 A-scans in parallel at the camera's frame rate of 281 frame per second, achieving an equivalent rate of over 300,000 A-scan/s, while minimizing sacrifice in the point spread function (2.8 × 3.1 × 3.2 µm3, x × y × z) and the field of view (750 × 750 × 750 µm3). As an example of application, we presented high-speed imaging of blood oxygenation in the rodent brain cortex.
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Affiliation(s)
- Fangjian Xing
- School of Computer and Electronic information, Nanjing Normal University, Nanjing, 210023, China
- Center for Biomedical Engineering, School of Engineering, Brown University, Providence, Rhode Island 02912, USA
| | - Jang-Hoon Lee
- Center for Biomedical Engineering, School of Engineering, Brown University, Providence, Rhode Island 02912, USA
| | - Collin Polucha
- Center for Biomedical Engineering, School of Engineering, Brown University, Providence, Rhode Island 02912, USA
| | - Jonghwan Lee
- Center for Biomedical Engineering, School of Engineering, Brown University, Providence, Rhode Island 02912, USA
- Carney Institute for Brain Science, Brown University, Providence, Rhode Island 02912, USA
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20
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Chen F, Si P, de la Zerda A, Jokerst JV, Myung D. Gold nanoparticles to enhance ophthalmic imaging. Biomater Sci 2021; 9:367-390. [PMID: 33057463 PMCID: PMC8063223 DOI: 10.1039/d0bm01063d] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The use of gold nanoparticles as diagnostic tools is burgeoning, especially in the cancer community with a focus on theranostic applications to both cancer diagnosis and treatment. Gold nanoparticles have also demonstrated great potential for use in diagnostic and therapeutic approaches in ophthalmology. Although many ophthalmic imaging modalities are available, there is still a considerable unmet need, in particular for ophthalmic molecular imaging for the early detection of eye disease before morphological changes are more grossly visible. An understanding of how gold nanoparticles are leveraged in other fields could inform new ways they could be utilized in ophthalmology. In this paper, we review current ophthalmic imaging techniques and then identify optical coherence tomography (OCT) and photoacoustic imaging (PAI) as the most promising technologies amenable to the use of gold nanoparticles for molecular imaging. Within this context, the development of gold nanoparticles as OCT and PAI contrast agents are reviewed, with the most recent developments described in detail.
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Affiliation(s)
- Fang Chen
- Mary M. and Sash A. Spencer Center for Vision Research, Byers Eye Institute, Department of Ophthalmology, Stanford University, CA 94305, USA.
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21
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Rubinoff I, Kuranov RV, Zhang HF. Intrinsic spectrally-dependent background in spectroscopic visible-light optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2021; 12:110-124. [PMID: 33520380 PMCID: PMC7818955 DOI: 10.1364/boe.410011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/15/2020] [Accepted: 11/16/2020] [Indexed: 05/10/2023]
Abstract
Visible-light optical coherence tomography (vis-OCT) has enabled new spectroscopic applications, such as retinal oximetry, as a result of increased optical absorption and scattering contacts in biological tissue and improved axial resolution. Besides extracting tissue properties from back-scattered light, spectroscopic analyses must consider spectral alterations induced by image reconstruction itself. We investigated an intrinsic spectral bias in the background noise floor, which is hereby referred to as the spectrally-dependent background (SDBG). We developed an analytical model to predict the SDBG-induced bias and validated this model using numerically simulated and experimentally acquired data. We found that SDBG systemically altered the measured spectra of blood in human retinal vessels in vis-OCT, as compared to literature data. We provided solutions to quantify and compensate for SDBG in retinal oximetry. This work is particularly significant for clinical applications of vis-OCT.
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Affiliation(s)
- Ian Rubinoff
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Roman V. Kuranov
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
- Opticent Health, Evanston, IL 60201, USA
| | - Hao F. Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
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22
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Intravital Optical Imaging to Monitor Anti-Tumor Immunological Response in Preclinical Models. Bioanalysis 2021. [DOI: 10.1007/978-3-030-78338-9_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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23
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Everett M, Magazzeni S, Schmoll T, Kempe M. Optical coherence tomography: From technology to applications in ophthalmology. TRANSLATIONAL BIOPHOTONICS 2020. [DOI: 10.1002/tbio.202000012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
| | | | - Tilman Schmoll
- Carl Zeiss Meditec Inc. Dublin California USA
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
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24
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Martell MT, Haven NJM, Zemp RJ. Multimodal imaging with spectral-domain optical coherence tomography and photoacoustic remote sensing microscopy. OPTICS LETTERS 2020; 45:4859-4862. [PMID: 32870876 DOI: 10.1364/ol.398940] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
We develop a multimodal imaging platform, combining depth-resolved scattering contrast from spectral-domain optical coherence tomography (SD-OCT) with complementary, non-contact absorption contrast using photoacoustic remote sensing (PARS) microscopy. The system provides a widefield OCT mode using a telecentric scan lens, and a high-resolution, dual-contrast mode using a 0.26 numerical aperture apochromatic objective. An interlaced acquisition approach is used to achieve simultaneous, co-registered imaging. The SD-OCT modality provides a 9.7 µm axial resolution. Comprehensive in vivo imaging of a nude mouse ear is demonstrated, with the SD-OCT scattering intensity revealing dermal morphology, and PARS microscopy providing a map of microvasculature.
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25
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Zhang T, Kho AM, Srinivasan VJ. Water wavenumber calibration for visible light optical coherence tomography. JOURNAL OF BIOMEDICAL OPTICS 2020; 25:JBO-200166LR. [PMID: 32935500 PMCID: PMC7490762 DOI: 10.1117/1.jbo.25.9.090501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 08/28/2020] [Indexed: 06/11/2023]
Abstract
SIGNIFICANCE Visible light optical coherence tomography (OCT) is emerging for spectroscopic and ultrahigh resolution imaging, but challenges remain. Depth-dependent dispersion limits retinal image quality and current correction approaches are cumbersome. Inconsistent group refractive indices during image reconstruction also limit reproducibility. AIM To introduce and evaluate water wavenumber calibration (WWC), which corrects depth-dependent dispersion and provides an accurate depth axis in water. APPROACH Enabled by a visible light OCT spectrometer configuration with a 3- to 4-dB sensitivity roll-off over 1 mm in air across a 90-nm bandwidth, we determine the spectral phase of a 1-mm water cell, an affine function of water wavenumber. Via WWC, we reconstruct visible light OCT human retinal images with 1.3-μm depth resolution in water. RESULTS Images clearly reveal Bruch's membrane, inner plexiform layer lamination, and a thin nerve fiber layer in the temporal parafovea. WWC halves the processing time, while achieving the same image definition as an assumption-free gold standard approach, suggesting that water wavenumber is a suitable proxy for tissue wavenumber. WWC also provides a depth axis in water without explicitly assuming a group refractive index. CONCLUSIONS WWC is a simple method that helps to realize the full potential of visible light OCT.
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Affiliation(s)
- Tingwei Zhang
- University of California Davis, Department of Biomedical Engineering, Davis, California, United States
| | - Aaron M. Kho
- University of California Davis, Department of Biomedical Engineering, Davis, California, United States
| | - Vivek J. Srinivasan
- University of California Davis, Department of Biomedical Engineering, Davis, California, United States
- University of California Davis, School of Medicine, Department of Ophthalmology and Vision Science, Sacramento, California, United States
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26
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Chen X, Kandel ME, Hu C, Lee YJ, Popescu G. Wolf phase tomography (WPT) of transparent structures using partially coherent illumination. LIGHT, SCIENCE & APPLICATIONS 2020; 9:142. [PMID: 32864117 DOI: 10.1117/12.2582903] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 07/30/2020] [Accepted: 08/03/2020] [Indexed: 05/27/2023]
Abstract
In 1969, Emil Wolf proposed diffraction tomography using coherent holographic imaging to extract 3D information from transparent, inhomogeneous objects. In the same era, the Wolf equations were first used to describe the propagation correlations associated with partially coherent fields. Combining these two concepts, we present Wolf phase tomography (WPT), which is a method for performing diffraction tomography using partially coherent fields. WPT reconstruction works directly in the space-time domain, without the need for Fourier transformation, and decouples the refractive index (RI) distribution from the thickness of the sample. We demonstrate the WPT principle using the data acquired by a quantitative-phase-imaging method that upgrades an existing phase-contrast microscope by introducing controlled phase shifts between the incident and scattered fields. The illumination field in WPT is partially spatially coherent (emerging from a ring-shaped pupil function) and of low temporal coherence (white light), and as such, it is well suited for the Wolf equations. From three intensity measurements corresponding to different phase-contrast frames, the 3D RI distribution is obtained immediately by computing the Laplacian and second time derivative of the measured complex correlation function. We validate WPT with measurements of standard samples (microbeads), spermatozoa, and live neural cultures. The high throughput and simplicity of this method enables the study of 3D, dynamic events in living cells across the entire multiwell plate, with an RI sensitivity on the order of 10-5.
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Affiliation(s)
- Xi Chen
- Quantitative Light Imaging Laboratory, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Mikhail E Kandel
- Quantitative Light Imaging Laboratory, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Chenfei Hu
- Quantitative Light Imaging Laboratory, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Young Jae Lee
- Quantitative Light Imaging Laboratory, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Gabriel Popescu
- Quantitative Light Imaging Laboratory, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
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27
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Chen X, Kandel ME, Hu C, Lee YJ, Popescu G. Wolf phase tomography (WPT) of transparent structures using partially coherent illumination. LIGHT, SCIENCE & APPLICATIONS 2020; 9:142. [PMID: 32864117 PMCID: PMC7438521 DOI: 10.1038/s41377-020-00379-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 07/30/2020] [Accepted: 08/03/2020] [Indexed: 05/03/2023]
Abstract
In 1969, Emil Wolf proposed diffraction tomography using coherent holographic imaging to extract 3D information from transparent, inhomogeneous objects. In the same era, the Wolf equations were first used to describe the propagation correlations associated with partially coherent fields. Combining these two concepts, we present Wolf phase tomography (WPT), which is a method for performing diffraction tomography using partially coherent fields. WPT reconstruction works directly in the space-time domain, without the need for Fourier transformation, and decouples the refractive index (RI) distribution from the thickness of the sample. We demonstrate the WPT principle using the data acquired by a quantitative-phase-imaging method that upgrades an existing phase-contrast microscope by introducing controlled phase shifts between the incident and scattered fields. The illumination field in WPT is partially spatially coherent (emerging from a ring-shaped pupil function) and of low temporal coherence (white light), and as such, it is well suited for the Wolf equations. From three intensity measurements corresponding to different phase-contrast frames, the 3D RI distribution is obtained immediately by computing the Laplacian and second time derivative of the measured complex correlation function. We validate WPT with measurements of standard samples (microbeads), spermatozoa, and live neural cultures. The high throughput and simplicity of this method enables the study of 3D, dynamic events in living cells across the entire multiwell plate, with an RI sensitivity on the order of 10-5.
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Affiliation(s)
- Xi Chen
- Quantitative Light Imaging Laboratory, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Mikhail E. Kandel
- Quantitative Light Imaging Laboratory, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Chenfei Hu
- Quantitative Light Imaging Laboratory, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Young Jae Lee
- Quantitative Light Imaging Laboratory, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Gabriel Popescu
- Quantitative Light Imaging Laboratory, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
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28
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Wang G, Le NM, Hu X, Cheng Y, Jacques SL, Subhash H, Wang RK. Semi-automated registration and segmentation for gingival tissue volume measurement on 3D OCT images. BIOMEDICAL OPTICS EXPRESS 2020; 11:4536-4547. [PMID: 32923062 PMCID: PMC7449737 DOI: 10.1364/boe.396599] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 06/28/2020] [Accepted: 07/17/2020] [Indexed: 05/17/2023]
Abstract
The change in gingival tissue volume may be used to indicate changes in gingival inflammation, which may be useful for the clinical assessment of gingival health. Properly quantifying gingival tissue volume requires a robust technique for accurate registration and segmentation of longitudinally captured 3-dimensional (3D) images. In this paper, a semi-automated registration and segmentation method for micrometer resolution measurement of gingival-tissue volume is proposed for 3D optical coherence tomography (OCT) imaging. For quantification, relative changes in gingiva tissue volume are measured based on changes in the gingiva surface height using the tooth surface as a reference. This report conducted repeatability tests on this method drawn from repeated scans in one patient, indicating an error of the point cloud registration method for oral OCT imaging is 63.08 ± 4.52µm (1σ), and the measurement error of the gingival tissue average thickness is -3.40 ± 21.85µm (1σ).
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Affiliation(s)
- Geng Wang
- University of Washington, Department of
Bioengineering, Seattle, WA 98195, USA
| | - Nhan Minh Le
- University of Washington, Department of
Bioengineering, Seattle, WA 98195, USA
| | - Xiaohui Hu
- University of Washington, Department of
Bioengineering, Seattle, WA 98195, USA
| | - Yuxuan Cheng
- University of Washington, Department of
Bioengineering, Seattle, WA 98195, USA
| | - Steven L. Jacques
- University of Washington, Department of
Bioengineering, Seattle, WA 98195, USA
| | - Hrebesh Subhash
- Clinical Method Development - Oral Care,
Colgate-Palmolive Company, Piscataway, NJ 08854, USA
| | - Ruikang K. Wang
- University of Washington, Department of
Bioengineering, Seattle, WA 98195, USA
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29
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Lu GJ, Chou LD, Malounda D, Patel AK, Welsbie DS, Chao DL, Ramalingam T, Shapiro MG. Genetically Encodable Contrast Agents for Optical Coherence Tomography. ACS NANO 2020; 14:7823-7831. [PMID: 32023037 PMCID: PMC7685218 DOI: 10.1021/acsnano.9b08432] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Optical coherence tomography (OCT) has gained wide adoption in biological research and medical imaging due to its exceptional tissue penetration, 3D imaging speed, and rich contrast. However, OCT plays a relatively small role in molecular and cellular imaging due to the lack of suitable biomolecular contrast agents. In particular, while the green fluorescent protein has provided revolutionary capabilities to fluorescence microscopy by connecting it to cellular functions such as gene expression, no equivalent reporter gene is currently available for OCT. Here, we introduce gas vesicles, a class of naturally evolved gas-filled protein nanostructures, as genetically encodable OCT contrast agents. The differential refractive index of their gas compartments relative to surrounding aqueous tissue and their nanoscale motion enables gas vesicles to be detected by static and dynamic OCT. Furthermore, the OCT contrast of gas vesicles can be selectively erased in situ with ultrasound, allowing unambiguous assignment of their location. In addition, gas vesicle clustering modulates their temporal signal, enabling the design of dynamic biosensors. We demonstrate the use of gas vesicles as reporter genes in bacterial colonies and as purified contrast agents in vivo in the mouse retina. Our results expand the utility of OCT to image a wider variety of cellular and molecular processes.
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Affiliation(s)
- George J. Lu
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Li-dek Chou
- OCT Medical Imaging Inc., 9272 Jeronimo Road, Irvine, CA 92618, USA
| | - Dina Malounda
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Amit K. Patel
- Shiley Eye Institute, Andrew Viterbi Department of Ophthalmology, University of California San Diego, La Jolla, CA 92093, USA
| | - Derek S. Welsbie
- Shiley Eye Institute, Andrew Viterbi Department of Ophthalmology, University of California San Diego, La Jolla, CA 92093, USA
| | - Daniel L. Chao
- Shiley Eye Institute, Andrew Viterbi Department of Ophthalmology, University of California San Diego, La Jolla, CA 92093, USA
| | | | - Mikhail G. Shapiro
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
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Song W, Shao W, Yi W, Liu R, Desai M, Ness S, Yi J. Visible light optical coherence tomography angiography (vis-OCTA) facilitates local microvascular oximetry in the human retina. BIOMEDICAL OPTICS EXPRESS 2020; 11:4037-4051. [PMID: 33014584 PMCID: PMC7510897 DOI: 10.1364/boe.395843] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 06/18/2020] [Accepted: 06/22/2020] [Indexed: 05/06/2023]
Abstract
We report herein the first visible light optical coherence tomography angiography (vis-OCTA) for human retinal imaging. Compared to the existing vis-OCT systems, we devised a spectrometer with a narrower bandwidth to increase the spectral power density for OCTA imaging, while retaining the major spectral contrast in the blood. We achieved a 100 kHz A-line rate, the fastest acquisition speed reported so far for human retinal vis-OCT. We rigorously optimized the imaging protocol such that a single acquisition took < 6 seconds with a field of view (FOV) of 3×7.8 mm2. The angiography enables accurate localization of microvasculature down to the capillary level and thus enables oximetry at vessels < 100 µm in diameter. We demonstrated microvascular hemoglobin oxygen saturation (sO2) at the feeding and draining vessels at the perifoveal region. The longitudinal repeatability was assessed by < 5% coefficient of variation (CV). The unique capabilities of our vis-OCTA system may allow studies on the role of microvascular oxygen in various retinal pathologies.
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Affiliation(s)
- Weiye Song
- Department of Medicine, Boston University School of Medicine, Boston Medical Center, Boston 02118, USA
| | - Wenjun Shao
- Department of Medicine, Boston University School of Medicine, Boston Medical Center, Boston 02118, USA
| | - Wei Yi
- Department of Medicine, Boston University School of Medicine, Boston Medical Center, Boston 02118, USA
| | - Rongrong Liu
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Manishi Desai
- Department of Ophthalmology, Boston University School of Medicine, Boston Medical Center, Boston 02118, USA
| | - Steven Ness
- Department of Ophthalmology, Boston University School of Medicine, Boston Medical Center, Boston 02118, USA
| | - Ji Yi
- Department of Medicine, Boston University School of Medicine, Boston Medical Center, Boston 02118, USA
- Department of Biomedical Engineering, Boston University, Boston 02118, USA
- Department of Electronic and Computer Engineering, Boston University, Boston 02118, USA
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31
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Srinivasan VJ, Moshiri A. Imaging oxygenation of retinal capillaries with depth resolution. Proc Natl Acad Sci U S A 2020; 117:14626-14628. [PMID: 32554605 PMCID: PMC7334518 DOI: 10.1073/pnas.2008404117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Vivek J Srinivasan
- Biomedical Engineering Department, University of California, Davis, CA 95616;
- Department of Ophthalmology and Vision Science, University of California Davis School of Medicine, Sacramento, CA 95817
| | - Ala Moshiri
- Department of Ophthalmology and Vision Science, University of California Davis School of Medicine, Sacramento, CA 95817
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32
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Zhou KC, Qian R, Farsiu S, Izatt JA. Spectroscopic optical coherence refraction tomography. OPTICS LETTERS 2020; 45:2091-2094. [PMID: 32236076 DOI: 10.1364/ol.389703] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 03/05/2020] [Indexed: 05/24/2023]
Abstract
In optical coherence tomography (OCT), the axial resolution is often superior to the lateral resolution, which is sacrificed for long imaging depths. To address this anisotropy, we previously developed optical coherence refraction tomography (OCRT), which uses images from multiple angles to computationally reconstruct an image with isotropic resolution, given by the OCT axial resolution. On the other hand, spectroscopic OCT (SOCT), an extension of OCT, trades axial resolution for spectral resolution and hence often has superior lateral resolution. Here, we present spectroscopic OCRT (SOCRT), which uses SOCT images from multiple angles to reconstruct a spectroscopic image with isotropic spatial resolution limited by the OCT lateral resolution. We experimentally show that SOCRT can estimate bead size based on Mie theory at simultaneously high spectral and isotropic spatial resolution. We also applied SOCRT to a biological sample, achieving axial resolution enhancement limited by the lateral resolution.
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33
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Sahoo GR, Dey R, Das N, Ghosh N, Pradhan A. Two dimensional multifractal detrended fluctuation analysis of low coherence images for diagnosis of cervical pre-cancer. Biomed Phys Eng Express 2020; 6:025011. [PMID: 33438637 DOI: 10.1088/2057-1976/ab6e17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We report detection of cervical pre-cancer through their low coherence images by applying two dimensional multifractal detrended fluctuation analysis. Low coherent backscattered images of pre-cancerous cervical tissue sections were captured using a common path interferometric setup. The captured images contain both depth and lateral information of the spatial variation in refractive index (RI) occurring with progression of cervical pre-cancer. A two-dimensional multifractal detrended fluctuation analysis (2D MFDFA) was applied on these low coherent images to study the variations occurring in their fractal nature. Long-range correlations were observed in the RI fluctuations and the strength of multifractality was found to be stronger for higher grades of cervical pre-cancer. A combination of derived multifractal parameters, namely, the generalized Hurst exponent and width of singularity spectrum showed clear differences among the different grades of pre-cancers. Normal, CIN-I and CIN-II were clearly discriminated by application of support vector machine (SVM) using radial Bessel function (RBF) kernel. The specificities and sensitivities between normal and CIN-I, CIN-I and CIN-II and normal and CIN-II were found to be 94%, 88% and 93%, 96% and 98%, 100% respectively.
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Yoon C, Qi Y, Mestre H, Canavesi C, Marola OJ, Cogliati A, Nedergaard M, Libby RT, Rolland JP. Gabor domain optical coherence microscopy combined with laser scanning confocal fluorescence microscopy. BIOMEDICAL OPTICS EXPRESS 2019; 10:6242-6257. [PMID: 31853397 PMCID: PMC6913392 DOI: 10.1364/boe.10.006242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 10/26/2019] [Accepted: 11/05/2019] [Indexed: 06/10/2023]
Abstract
We report on the development of fluorescence Gabor domain optical coherence microscopy (Fluo GD-OCM), a combination of GD-OCM with laser scanning confocal fluorescence microscopy (LSCFM) for synchronous micro-structural and fluorescence imaging. The dynamic focusing capability of GD-OCM provided the adaptive illumination environment for both modalities without any mechanical movement. Using Fluo GD-OCM, we imaged ex vivo DsRed-expressing cells in the brain of a transgenic mouse, as well as Cy3-labeled ganglion cells and Cy3-labeled astrocytes from a mouse retina. The self-registration of images taken by the two different imaging modalities showed the potential for a correlative study of subjects and double identification of the target.
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Affiliation(s)
- Changsik Yoon
- The Institute of Optics, University of Rochester, Wilmot Building, Rochester, New York 14627, USA
| | - Yue Qi
- Department of Biomedical Engineering, University of Rochester, Robert B. Goergen Hall, Rochester, New York 14627, USA
| | - Humberto Mestre
- Center for Translational Neuromedicine, Department of Neurosurgery, University of Rochester Medical Center, Rochester, New York 14642, USA
| | - Cristina Canavesi
- LighTopTech Corp., 150 Lucius Gordon Dr., Ste 201, West Henrietta, New York 14586, USA
| | - Olivia J. Marola
- Flaum Eye Institute, Department of Ophthalmology, University of Rochester Medical Center, Rochester, New York 14642, USA
| | - Andrea Cogliati
- LighTopTech Corp., 150 Lucius Gordon Dr., Ste 201, West Henrietta, New York 14586, USA
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, Department of Neurosurgery, University of Rochester Medical Center, Rochester, New York 14642, USA
| | - Richard T. Libby
- Flaum Eye Institute, Department of Ophthalmology, University of Rochester Medical Center, Rochester, New York 14642, USA
| | - Jannick P. Rolland
- The Institute of Optics, University of Rochester, Wilmot Building, Rochester, New York 14627, USA
- Department of Biomedical Engineering, University of Rochester, Robert B. Goergen Hall, Rochester, New York 14627, USA
- LighTopTech Corp., 150 Lucius Gordon Dr., Ste 201, West Henrietta, New York 14586, USA
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35
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Harper DJ, Konegger T, Augustin M, Schützenberger K, Eugui P, Lichtenegger A, Merkle CW, Hitzenberger CK, Glösmann M, Baumann B. Hyperspectral optical coherence tomography for in vivo visualization of melanin in the retinal pigment epithelium. JOURNAL OF BIOPHOTONICS 2019; 12:e201900153. [PMID: 31334610 PMCID: PMC7065636 DOI: 10.1002/jbio.201900153] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 06/19/2019] [Accepted: 07/18/2019] [Indexed: 05/09/2023]
Abstract
Previous studies for melanin visualization in the retinal pigment epithelium (RPE) have exploited either its absorption properties (using photoacoustic tomography or photothermal optical coherence tomography [OCT]) or its depolarization properties (using polarization sensitive OCT). However, these methods are only suitable when the melanin concentration is sufficiently high. In this work, we present the concept of hyperspectral OCT for melanin visualization in the RPE when the concentration is low. Based on white light OCT, a hyperspectral stack of 27 wavelengths (440-700 nm) was created in post-processing for each depth-resolved image. Owing to the size and shape of the melanin granules in the RPE, the variations in backscattering coefficient as a function of wavelength could be identified-a result which is to be expected from Mie theory. This effect was successfully identified both in eumelanin-containing phantoms and in vivo in the low-concentration Brown Norway rat RPE.
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Affiliation(s)
- Danielle J. Harper
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Thomas Konegger
- Institute of Chemical Technologies and Analytics, TU WienViennaAustria
| | - Marco Augustin
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Kornelia Schützenberger
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Pablo Eugui
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Antonia Lichtenegger
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Conrad W. Merkle
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | | | - Martin Glösmann
- Core Facility for Research and TechnologyUniversity of Veterinary MedicineViennaAustria
| | - Bernhard Baumann
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
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Liu R, Cheng S, Tian L, Yi J. Deep spectral learning for label-free optical imaging oximetry with uncertainty quantification. LIGHT, SCIENCE & APPLICATIONS 2019; 8:102. [PMID: 31754429 PMCID: PMC6864044 DOI: 10.1038/s41377-019-0216-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 10/17/2019] [Accepted: 11/01/2019] [Indexed: 05/06/2023]
Abstract
Measurement of blood oxygen saturation (sO2) by optical imaging oximetry provides invaluable insight into local tissue functions and metabolism. Despite different embodiments and modalities, all label-free optical-imaging oximetry techniques utilize the same principle of sO2-dependent spectral contrast from haemoglobin. Traditional approaches for quantifying sO2 often rely on analytical models that are fitted by the spectral measurements. These approaches in practice suffer from uncertainties due to biological variability, tissue geometry, light scattering, systemic spectral bias, and variations in the experimental conditions. Here, we propose a new data-driven approach, termed deep spectral learning (DSL), to achieve oximetry that is highly robust to experimental variations and, more importantly, able to provide uncertainty quantification for each sO2 prediction. To demonstrate the robustness and generalizability of DSL, we analyse data from two visible light optical coherence tomography (vis-OCT) setups across two separate in vivo experiments on rat retinas. Predictions made by DSL are highly adaptive to experimental variabilities as well as the depth-dependent backscattering spectra. Two neural-network-based models are tested and compared with the traditional least-squares fitting (LSF) method. The DSL-predicted sO2 shows significantly lower mean-square errors than those of the LSF. For the first time, we have demonstrated en face maps of retinal oximetry along with a pixel-wise confidence assessment. Our DSL overcomes several limitations of traditional approaches and provides a more flexible, robust, and reliable deep learning approach for in vivo non-invasive label-free optical oximetry.
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Affiliation(s)
- Rongrong Liu
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208 USA
| | - Shiyi Cheng
- Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215 USA
| | - Lei Tian
- Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215 USA
| | - Ji Yi
- Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215 USA
- Department of Biomedical Engineering, Boston University, Boston, MA 02215 USA
- Department of Medicine, Boston University School of Medicine, Boston Medical Center, Boston, MA 02118 USA
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37
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Ge X, Tang H, Wang X, Liu X, Chen S, Wang N, Ni G, Yu X, Chen S, Liang H, Bo E, Wang L, Braganza CS, Xu C, Rowe SM, Tearney GJ, Liu L. Geometry-Dependent Spectroscopic Contrast in Deep Tissues. iScience 2019; 19:965-975. [PMID: 31522119 PMCID: PMC6745491 DOI: 10.1016/j.isci.2019.08.046] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 07/10/2019] [Accepted: 08/22/2019] [Indexed: 12/19/2022] Open
Abstract
Nano-structures of biological systems can produce diverse spectroscopic effects through interactions with broadband light. Although structured coloration at the surface has been extensively studied, natural spectroscopic contrasts in deep tissues are poorly understood, which may carry valuable information for evaluating the anatomy and function of biological systems. Here we investigated the spectroscopic characteristics of an important geometry in deep tissues at the nanometer scale: packed nano-cylinders, in the near-infrared window, numerically predicted and experimentally proved that transversely oriented and regularly arranged nano-cylinders could selectively backscatter light of the long wavelengths. Notably, we found that the spectroscopic contrast of nanoscale fibrous structures was sensitive to the pressure load, possibly owing to the changes in the orientation, the degree of alignment, and the spacing. To explore the underlying physical basis, we further developed an analytical model based on the radial distribution function in terms of their radius, refractive index, and spatial distribution.
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Affiliation(s)
- Xin Ge
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Republic of Singapore
| | - Hongying Tang
- College of Information, Mechanical and Electrical Engineering, Shanghai Normal University, Shanghai 200234, China
| | - Xianghong Wang
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Republic of Singapore
| | - Xinyu Liu
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Republic of Singapore
| | - Si Chen
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Republic of Singapore
| | - Nanshuo Wang
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Republic of Singapore
| | - Guangming Ni
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Xiaojun Yu
- School of Automation, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China
| | - Shufen Chen
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Republic of Singapore
| | - Haitao Liang
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Republic of Singapore
| | - En Bo
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Republic of Singapore
| | - Lulu Wang
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Republic of Singapore
| | - Cilwyn Shalitha Braganza
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Republic of Singapore
| | - Chenjie Xu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Republic of Singapore
| | - Steven M Rowe
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, AL 35294, USA; Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
| | - Guillermo J Tearney
- Wellman Center for Photomedicine, Harvard Medical School and Massachusetts General Hospital, Boston, MA 02114, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139, USA; Department of Pathology, Harvard Medical School and Massachusetts General Hospital, Boston, MA 02114, USA.
| | - Linbo Liu
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Republic of Singapore; School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Republic of Singapore.
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38
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Qian R, Huang WF, McNabb RP, Zhou KC, Liu QH, Kuo AN, Izatt JA. Ocular anterior chamber blood cell population differentiation using spectroscopic optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2019; 10:3281-3300. [PMID: 31467779 PMCID: PMC6706034 DOI: 10.1364/boe.10.003281] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 05/22/2019] [Accepted: 05/29/2019] [Indexed: 05/24/2023]
Abstract
There is potential clinical significance in identifying cellular responses in the anterior chamber (AC) of the eye, which can indicate hyphema (an accumulation of red blood cells [RBCs]) or aberrant intraocular inflammation (an accumulation of white blood cells [WBCs]). In this work, we developed a spectroscopic OCT analysis method to differentiate between populations of RBCs and subtypes of WBCs, including granulocytes, lymphocytes and monocytes, both in vitro and in ACs of porcine eyes. We developed an algorithm to track single cells within OCT data sets, and extracted the backscatter reflectance spectrum of each single cell from the detected interferograms using the short-time Fourier transform (STFT). A look-up table of Mie back-scattering spectra was generated and used to correlate the backscatter spectral features of single cells to their characteristic sizes. The extracted size distributions based on the best Mie spectra fit were significantly different between each cell type. We also studied theoretical backscattering models of single RBCs to further validate our experimental results. The described work is a promising step towards clinically differentiating and quantifying AC blood cell types.
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Affiliation(s)
- Ruobing Qian
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Wei-feng Huang
- Department of Electrical and Computer Engineering, Duke University, Durham, NC 27708, USA
| | - Ryan P. McNabb
- Department of Ophthalmology, Duke University Medical Center, NC 27710, USA
| | - Kevin C. Zhou
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Qing H. Liu
- Department of Electrical and Computer Engineering, Duke University, Durham, NC 27708, USA
| | - Anthony N. Kuo
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
- Department of Ophthalmology, Duke University Medical Center, NC 27710, USA
| | - Joseph A. Izatt
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
- Department of Ophthalmology, Duke University Medical Center, NC 27710, USA
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39
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Shu X, Beckmann L, Wang Y, Rubinoff I, Lucy K, Ishikawa H, Wollstein G, Fawzi AA, Schuman JS, Kuranov RV, Zhang HF. Designing visible-light optical coherence tomography towards clinics. Quant Imaging Med Surg 2019; 9:769-781. [PMID: 31281773 PMCID: PMC6571199 DOI: 10.21037/qims.2019.05.01] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 05/04/2019] [Indexed: 12/31/2022]
Abstract
BACKGROUND The capabilities of visible-light optical coherence tomography (vis-OCT) in noninvasive anatomical and functional retinal imaging have been demonstrated by multiple groups in both rodents and healthy human subjects. Translating laboratory prototypes to an integrated clinical-environment-friendly system is required to explore the full potential of vis-OCT in disease management. METHODS We developed and optimized a portable vis-OCT system for human retinal imaging in clinical settings. We acquired raster- and circular-scan images from both healthy and diseased human eyes. RESULTS The new vis-OCT provided high-quality retinal images of both subjects without any known eye diseases and patients with various retinal diseases, including retinal occlusive disease and diabetic retinopathy (DR) over a broad range of ages. CONCLUSIONS A newly designed vis-OCT system is sufficiently optimized to be suited for routine patients' examinations in clinics. Vis-OCT has the potential to add new anatomical and functional imaging capabilities to ophthalmic clinical care.
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Affiliation(s)
- Xiao Shu
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, USA
| | - Lisa Beckmann
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, USA
| | | | - Ian Rubinoff
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, USA
| | - Katie Lucy
- NYU Langone Eye Center, NYU School of Medicine, New York, NY, USA
| | - Hiroshi Ishikawa
- NYU Langone Eye Center, NYU School of Medicine, New York, NY, USA
| | - Gadi Wollstein
- NYU Langone Eye Center, NYU School of Medicine, New York, NY, USA
| | - Amani A. Fawzi
- Department of Ophthalmology, Northwestern University, Chicago, IL, USA
| | - Joel S. Schuman
- NYU Langone Eye Center, NYU School of Medicine, New York, NY, USA
| | - Roman V. Kuranov
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, USA
- Opticent Health, Evanston, IL, USA
| | - Hao F. Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, USA
- Department of Ophthalmology, Northwestern University, Chicago, IL, USA
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40
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Evaluation of the Returned Electromagnetic Signal from Retro-reflectors in Turbid Media. Sci Rep 2019; 9:6550. [PMID: 31024049 PMCID: PMC6484034 DOI: 10.1038/s41598-019-43059-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 04/08/2019] [Indexed: 11/15/2022] Open
Abstract
We provide first-principle theoretical and numerical simulations using the coherent Transfer Matrix Approach (TMA) to describe the behavior of the three main class of the optical beacons namely phase conjugators, reflectors, and retroreflectors within a turbid medium. Our theory describes the extraordinary enhancement (about 5 dB) offered by retroreflectors compared to reflectors in our detailed experiments and shows that they effectively act as local optical phase conjugators. Moreover, the performance of retroreflectors shows little degradation for increased light incident angles in turbid media, while the performance of reflectors degrades drastically. These results may find applications for detection of the echoes of electromagnetic radiation in turbid media.
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41
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Steelman ZA, Ho DS, Chu KK, Wax A. Light scattering methods for tissue diagnosis. OPTICA 2019; 6:479-489. [PMID: 33043100 PMCID: PMC7544148 DOI: 10.1364/optica.6.000479] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Light scattering has become a common biomedical research tool, enabling diagnostic sensitivity to myriad tissue alterations associated with disease. Light-tissue interactions are particularly attractive for diagnostics due to the variety of contrast mechanisms that can be used, including spectral, angle-resolved, and Fourier-domain detection. Photonic diagnostic tools offer further benefit in that they are non-ionizing, non-invasive, and give real-time feedback. In this review, we summarize recent innovations in light scattering technologies, with a focus on clinical achievements over the previous ten years.
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42
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Kho A, Srinivasan VJ. Compensating spatially dependent dispersion in visible light OCT. OPTICS LETTERS 2019; 44:775-778. [PMID: 30767984 PMCID: PMC6503663 DOI: 10.1364/ol.44.000775] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 01/06/2019] [Indexed: 05/02/2023]
Abstract
Visible light optical coherence tomography (OCT) has recently emerged in retinal imaging, with claims of micrometer-scale axial resolution and multi-color (sub-band) imaging. Here, we show that the large dispersion of optical glass and aqueous media, together with broad optical bandwidths often used in visible light OCT, compromises both of these claims. To rectify this, we introduce the notion of spatially dependent (i.e., depth and transverse position-dependent) dispersion. We use a novel sub-band, sub-image correlation algorithm to estimate spatially dependent dispersion in our 109 nm bandwidth visible light OCT mouse retinal imaging system centered at 587 nm. After carefully compensating spatially dependent dispersion, we achieve delineation of fine outer retinal bands in mouse strains of varying pigmentation. Spatially dependent dispersion correction is critical for broader bandwidths and shorter visible wavelengths.
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Affiliation(s)
- Aaron Kho
- Department of Biomedical Engineering, University of California, Davis, California 95616, USA
| | - Vivek J. Srinivasan
- Department of Biomedical Engineering, University of California, Davis, California 95616, USA
- Department of Ophthalmology and Vision Science, University of California Davis School of Medicine, Sacramento, California 96817, USA
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43
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Liu R, Song W, Backman V, Yi J. Quantitative quality-control metrics for in vivo oximetry in small vessels by visible light optical coherence tomography angiography. BIOMEDICAL OPTICS EXPRESS 2019; 10:465-486. [PMID: 30800493 PMCID: PMC6377897 DOI: 10.1364/boe.10.000465] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 12/14/2018] [Accepted: 12/14/2018] [Indexed: 05/23/2023]
Abstract
Biological functions rely on local microvasculature to deliver oxygen and nutrients and carry away metabolic waste. Alterations to local oxygenation levels are manifested in diseases including cancer, diabetes mellitus, etc. The ability to quantify oxygen saturation (sO2) within microvasculature in vivo to assess local tissue oxygenation and metabolic function is highly sought after. Visible light optical coherence tomography (vis-OCT) angiography has shown promise in reaching this goal. However, achieving reliable measurements in small vessels can be challenging due to the reduced contrast and requires data averaging to improve the spectral data quality. Therefore, a method for quality-control of the vis-OCT data from small vessels becomes essential to reject unreliable readings. In this work, we present a quantitative metrics to evaluate the spectral data for a reliable measurement of sO2, including angiography signal to noise ratio (SNR), spectral anomaly detection and discard, and theory-experiment correlation analysis. The thresholds for each quantity can be flexibly adjusted according to different applications and system performance. We used these metrics to measure sO2 of C57BL/6J mouse lower extremity microvasculature and validated it by introducing hyperoxia for expected sO2 changes. After validation, we applied this protocol on C57BL/6J mouse ear microvasculature to conduct in vivo small blood vessel OCT oximetry. This work seeks to standardize the data processing method for in vivo oximetry in small vessels by vis-OCT.
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Affiliation(s)
- Rongrong Liu
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Weiye Song
- Department of Medicine, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Vadim Backman
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Ji Yi
- Department of Medicine, Boston University School of Medicine, Boston, MA, 02118, USA
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Israelsen NM, Petersen CR, Barh A, Jain D, Jensen M, Hannesschläger G, Tidemand-Lichtenberg P, Pedersen C, Podoleanu A, Bang O. Real-time high-resolution mid-infrared optical coherence tomography. LIGHT, SCIENCE & APPLICATIONS 2019; 8:11. [PMID: 30675345 PMCID: PMC6342823 DOI: 10.1038/s41377-019-0122-5] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 01/07/2019] [Accepted: 01/07/2019] [Indexed: 05/05/2023]
Abstract
The potential for improving the penetration depth of optical coherence tomography systems by using light sources with longer wavelengths has been known since the inception of the technique in the early 1990s. Nevertheless, the development of mid-infrared optical coherence tomography has long been challenged by the maturity and fidelity of optical components in this spectral region, resulting in slow acquisition, low sensitivity, and poor axial resolution. In this work, a mid-infrared spectral-domain optical coherence tomography system operating at a central wavelength of 4 µm and an axial resolution of 8.6 µm is demonstrated. The system produces two-dimensional cross-sectional images in real time enabled by a high-brightness 0.9- to 4.7-µm mid-infrared supercontinuum source with a pulse repetition rate of 1 MHz for illumination and broadband upconversion of more than 1-µm bandwidth from 3.58-4.63 µm to 820-865 nm, where a standard 800-nm spectrometer can be used for fast detection. The images produced by the mid-infrared system are compared with those delivered by a state-of-the-art ultra-high-resolution near-infrared optical coherence tomography system operating at 1.3 μm, and the potential applications and samples suited for this technology are discussed. In doing so, the first practical mid-infrared optical coherence tomography system is demonstrated, with immediate applications in real-time non-destructive testing for the inspection of defects and thickness measurements in samples that exhibit strong scattering at shorter wavelengths.
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Affiliation(s)
- Niels M. Israelsen
- DTU Fotonik, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark
- NORBLIS IVS, Virumgade 35 D, Virum, 2830 Denmark
| | - Christian R. Petersen
- DTU Fotonik, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark
- NORBLIS IVS, Virumgade 35 D, Virum, 2830 Denmark
| | - Ajanta Barh
- DTU Fotonik, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark
| | - Deepak Jain
- DTU Fotonik, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark
| | - Mikkel Jensen
- DTU Fotonik, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark
| | - Günther Hannesschläger
- Research Center for Non-Destructive Testing (RECENDT), Altenberger Straße 69, 4040 Linz, Austria
| | - Peter Tidemand-Lichtenberg
- DTU Fotonik, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark
- NLIR ApS, Hirsemarken 1, Farum, 3520 Denmark
| | - Christian Pedersen
- DTU Fotonik, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark
- NLIR ApS, Hirsemarken 1, Farum, 3520 Denmark
| | - Adrian Podoleanu
- Applied Optics Group, School of Physical Sciences, University of Kent, Canterbury, CT2 7NH UK
| | - Ole Bang
- DTU Fotonik, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark
- NORBLIS IVS, Virumgade 35 D, Virum, 2830 Denmark
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Winkelmann JA, Eid A, Spicer G, Almassalha LM, Nguyen TQ, Backman V. Spectral contrast optical coherence tomography angiography enables single-scan vessel imaging. LIGHT, SCIENCE & APPLICATIONS 2019; 8:7. [PMID: 30651982 PMCID: PMC6333625 DOI: 10.1038/s41377-018-0117-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 12/14/2018] [Accepted: 12/15/2018] [Indexed: 05/06/2023]
Abstract
Optical coherence tomography angiography relies on motion for contrast and requires at least two data acquisitions per pointwise scanning location. We present a method termed spectral contrast optical coherence tomography angiography using visible light that relies on the spectral signatures of blood for angiography from a single scan using endogenous contrast. We demonstrate the molecular sensitivity of this method, which enables lymphatic vessel, blood, and tissue discrimination.
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Affiliation(s)
- James A. Winkelmann
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208 USA
| | - Aya Eid
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208 USA
| | - Graham Spicer
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208 USA
| | - Luay M. Almassalha
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208 USA
| | - The-Quyen Nguyen
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208 USA
| | - Vadim Backman
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208 USA
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46
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Spectroscopic Optical Coherence Tomography by Using Multiple Multipole Expansion. PHOTONICS 2018. [DOI: 10.3390/photonics5040044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This paper presents a pre-processing method to remove multiple scattering artifacts in spectroscopic optical coherence tomography (SOCT) using time–frequency analysis approaches. The method uses a multiple multipole expansion approach to model the light fields in SOCT. It is shown that the multiple scattered fields can be characterized by higher order terms of the multiple multipole expansion. Hence, the multiple scattering artifact can thus be eliminated by applying the time–frequency transform on the SOCT measurements characterized by the lower order terms. Simulation and experimental results are presented to show the effectiveness of the proposed pre-processing method.
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Veenstra C, Petersen W, Vellekoop IM, Steenbergen W, Bosschaart N. Spatially confined quantification of bilirubin concentrations by spectroscopic visible-light optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2018; 9:3581-3589. [PMID: 30338141 PMCID: PMC6191639 DOI: 10.1364/boe.9.003581] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 05/09/2018] [Accepted: 06/06/2018] [Indexed: 05/18/2023]
Abstract
Spatially confined measurements of bilirubin in tissue can be of great value for noninvasive bilirubin estimations during neonatal jaundice, as well as our understanding of the physiology behind bilirubin extravasation. This work shows the potential of spectroscopic visible-light optical coherence tomography (sOCT) for this purpose. At the bilirubin absorption peak around 460 nm, sOCT suffers from a strong signal decay with depth, which we overcome by optimizing our system sensitivity through a combination of zero-delay acquisition and focus tracking. In a phantom study, we demonstrate the quantification of bilirubin concentrations between 0 and 650 µM with only a 10% difference to the expected value, thereby covering the entire clinical pathophysiological range.
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48
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Yang Q, Miao Y, Huo T, Li Y, Heidari E, Zhu J, Chen Z. Deep imaging in highly scattering media by combining reflection matrix measurement with Bessel-like beam based optical coherence tomography. APPLIED PHYSICS LETTERS 2018; 113:011106. [PMID: 30034015 PMCID: PMC6029932 DOI: 10.1063/1.5036661] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 06/11/2018] [Indexed: 05/25/2023]
Abstract
Multiple scattering in biomedical tissue limits the imaging depth within a range of 1-2 mm for conventional optical imaging techniques. To extend the imaging depth into the scattering medium, a computational method based on the reflection matrix measurement has been developed to retrieve the singly back-scattered signal light from the dominant detrimental multiple-scattered background. After applying singular value decomposition on the measured matrix in the post-process, the target image underneath the turbid media is clearly recovered. To increase the depth of focus of the incident light by elongating the focal spot along the optical axis, a digital grating pattern is specially designed and displayed on a phase-only spatial light modulator to generate the Bessel-like beam for lateral point scanning. According to the results, the depth of focus is increased up to 2.4 mm which is much longer than the value of ∼50 μm obtained by using the conventional focused Gaussian beam, leading to a deeper penetration depth due to the self-healing feature of the Bessel-like beam. In addition, generation of the Bessel-like beam simplifies the axial scanning process by getting rid of the need to mechanically translate the focal zone along the optical axis of an objective with a high numerical aperture. By combining this method with an optical coherence tomography system with a low coherence light source, a depth-resolved optical image is obtained underneath a highly turbid medium.
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Affiliation(s)
- Qiang Yang
- Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Road East, Irvine, California 92612, USA
| | | | - Tiancheng Huo
- Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Road East, Irvine, California 92612, USA
| | | | | | - Jiang Zhu
- Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Road East, Irvine, California 92612, USA
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Song W, Zhou L, Zhang S, Ness S, Desai M, Yi J. Fiber-based visible and near infrared optical coherence tomography (vnOCT) enables quantitative elastic light scattering spectroscopy in human retina. BIOMEDICAL OPTICS EXPRESS 2018; 9:3464-3480. [PMID: 29984110 PMCID: PMC6033571 DOI: 10.1364/boe.9.003464] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 06/09/2018] [Accepted: 06/21/2018] [Indexed: 05/18/2023]
Abstract
Elastic light scattering spectroscopy (ELSS) has been proven a powerful method in measuring tissue structures with exquisite nanoscale sensitivity. However, ELSS contrast in the living human retina has been relatively underexplored, primarily due to the lack of imaging tools with a large spectral bandwidth. Here, we report a simple all fiber-based setup to implement dual-channel visible and near infrared (NIR) optical coherence tomography (vnOCT) for human retinal imaging, bridging over a 300nm spectral gap. Remarkably, the fiber components in our vnOCT system support single-mode propagation for both visible and NIR light, both of which maintain excellent interference efficiencies with fringe visibility of 97% and 90%, respectively. The longitudinal chromatic aberration from the eye is corrected by a custom-designed achromatizing lens. The elegant fiber-based design enables simultaneous imaging for both channels and allows comprehensive ELSS analysis on several important anatomical layers, including nerve fiber layer, outer segment of the photoreceptors and retinal pigment epithelium. This vnOCT platform and method of ELSS analysis open new opportunities in understanding structure-function relationship in the human retina and in exploring new biomarkers for retinal diseases.
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Affiliation(s)
- Weiye Song
- Department of Medicine, Boston University School of Medicine, Boston Medical Center, Boston, MA 02118, USA
| | - Libo Zhou
- College of Electronic Science and Engineering, Jilin University, Changchun, Jilin, 130012, China
| | - Sui Zhang
- Danna-Farber Cancer Institute, Boston, MA 02215, USA
| | - Steven Ness
- Department of Ophthalmology, Boston Medical Center, Boston University School of Medicine, Boston, MA 02118, USA
| | - Manishi Desai
- Department of Ophthalmology, Boston Medical Center, Boston University School of Medicine, Boston, MA 02118, USA
| | - Ji Yi
- Department of Medicine, Boston University School of Medicine, Boston Medical Center, Boston, MA 02118, USA
- Department of Biomedical Engineering, Boston University, Boston, MA 02118, USA
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Harper DJ, Augustin M, Lichtenegger A, Eugui P, Reyes C, Glösmann M, Hitzenberger CK, Baumann B. White light polarization sensitive optical coherence tomography for sub-micron axial resolution and spectroscopic contrast in the murine retina. BIOMEDICAL OPTICS EXPRESS 2018; 9:2115-2129. [PMID: 29760974 PMCID: PMC5946775 DOI: 10.1364/boe.9.002115] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 03/29/2018] [Accepted: 03/30/2018] [Indexed: 05/03/2023]
Abstract
A white light polarization sensitive optical coherence tomography system has been developed, using a supercontinuum laser as the light source. By detecting backscattered light from 400 - 700 nm, an axial resolution of 1.0 µm in air was achieved. The system consists of a free-space interferometer and two homemade spectrometers that detect orthogonal polarization states. Following system specifications, images of a healthy murine retina as acquired by this non-contact system are presented, showing high resolution reflectivity images as well as spectroscopic and polarization sensitive contrast. Additional images of the very-low-density-lipoprotein-receptor (VLDLR) knockout mouse model were acquired. The high resolution allows the detection of small lesions in the retina.
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Affiliation(s)
- Danielle J. Harper
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4L, 1090 Vienna,
Austria
| | - Marco Augustin
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4L, 1090 Vienna,
Austria
| | - Antonia Lichtenegger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4L, 1090 Vienna,
Austria
| | - Pablo Eugui
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4L, 1090 Vienna,
Austria
| | - Carlos Reyes
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4L, 1090 Vienna,
Austria
| | - Martin Glösmann
- University of Veterinary Medicine Vienna, Core Facility for Research and Technology, Veterinaerplatz 1, 1210 Vienna,
Austria
| | - Christoph K. Hitzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4L, 1090 Vienna,
Austria
| | - Bernhard Baumann
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4L, 1090 Vienna,
Austria
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