1
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Mehta K, Daghsni M, Raeisossadati R, Xu Z, Davis E, Naidich A, Wang B, Tao S, Pi S, Chen W, Kostka D, Liu S, Gross JM, Kuwajima T, Aldiri I. A cis-regulatory module underlies retinal ganglion cell genesis and axonogenesis. Cell Rep 2024; 43:114291. [PMID: 38823017 DOI: 10.1016/j.celrep.2024.114291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 04/08/2024] [Accepted: 05/13/2024] [Indexed: 06/03/2024] Open
Abstract
Atoh7 is transiently expressed in retinal progenitor cells (RPCs) and is required for retinal ganglion cell (RGC) differentiation. In humans, a deletion in a distal non-coding regulatory region upstream of ATOH7 is associated with optic nerve atrophy and blindness. Here, we functionally interrogate the significance of the Atoh7 regulatory landscape to retinogenesis in mice. Deletion of the Atoh7 enhancer structure leads to RGC deficiency, optic nerve hypoplasia, and retinal blood vascular abnormalities, phenocopying inactivation of Atoh7. Further, loss of the Atoh7 remote enhancer impacts ipsilaterally projecting RGCs and disrupts proper axonal projections to the visual thalamus. Deletion of the Atoh7 remote enhancer is also associated with the dysregulation of axonogenesis genes, including the derepression of the axon repulsive cue Robo3. Our data provide insights into how Atoh7 enhancer elements function to promote RGC development and optic nerve formation and highlight a key role of Atoh7 in the transcriptional control of axon guidance molecules.
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Affiliation(s)
- Kamakshi Mehta
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Marwa Daghsni
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Reza Raeisossadati
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Zhongli Xu
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Emily Davis
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Abigail Naidich
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Bingjie Wang
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Shiyue Tao
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Shaohua Pi
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Wei Chen
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Dennis Kostka
- Department of Computational & Systems Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Silvia Liu
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Jeffrey M Gross
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Takaaki Kuwajima
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Louis J. Fox Center for Vision Restoration, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Issam Aldiri
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Department of Computational & Systems Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Louis J. Fox Center for Vision Restoration, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
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2
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Wang B, Ganjee R, Khandaker I, Flohr K, He Y, Li G, Wesalo J, Sahel JA, da Silva S, Pi S. Deep learning based characterization of human organoids using optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2024; 15:3112-3127. [PMID: 38855657 PMCID: PMC11161340 DOI: 10.1364/boe.515781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 03/11/2024] [Accepted: 04/08/2024] [Indexed: 06/11/2024]
Abstract
Organoids, derived from human induced pluripotent stem cells (hiPSCs), are intricate three-dimensional in vitro structures that mimic many key aspects of the complex morphology and functions of in vivo organs such as the retina and heart. Traditional histological methods, while crucial, often fall short in analyzing these dynamic structures due to their inherently static and destructive nature. In this study, we leveraged the capabilities of optical coherence tomography (OCT) for rapid, non-invasive imaging of both retinal, cerebral, and cardiac organoids. Complementing this, we developed a sophisticated deep learning approach to automatically segment the organoid tissues and their internal structures, such as hollows and chambers. Utilizing this advanced imaging and analysis platform, we quantitatively assessed critical parameters, including size, area, volume, and cardiac beating, offering a comprehensive live characterization and classification of the organoids. These findings provide profound insights into the differentiation and developmental processes of organoids, positioning quantitative OCT imaging as a potentially transformative tool for future organoid research.
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Affiliation(s)
- Bingjie Wang
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Razieh Ganjee
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Irona Khandaker
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Keevon Flohr
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Yuanhang He
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
- School of Medicine, Tsinghua University, Beijing 100084, China
| | - Guang Li
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Joshua Wesalo
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - José-Alain Sahel
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Susana da Silva
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Shaohua Pi
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, USA
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3
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Wang L, Chen S, Liu L, Yin X, Shi G, Mo J. Axial super-resolution optical coherence tomography via complex-valued network. Phys Med Biol 2023; 68:235016. [PMID: 37922558 DOI: 10.1088/1361-6560/ad0997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 11/03/2023] [Indexed: 11/07/2023]
Abstract
Optical coherence tomography (OCT) is a fast and non-invasive optical interferometric imaging technique that can provide high-resolution cross-sectional images of biological tissues. OCT's key strength is its depth resolving capability which remains invariant along the imaging depth and is determined by the axial resolution. The axial resolution is inversely proportional to the bandwidth of the OCT light source. Thus, the use of broadband light sources can effectively improve the axial resolution and however leads to an increased cost. In recent years, real-valued deep learning technique has been introduced to obtain super-resolution optical imaging. In this study, we proposed a complex-valued super-resolution network (CVSR-Net) to achieve an axial super-resolution for OCT by fully utilizing the amplitude and phase of OCT signal. The method was evaluated on three OCT datasets. The results show that the CVSR-Net outperforms its real-valued counterpart with a better depth resolving capability. Furthermore, comparisons were made between our network, six prevailing real-valued networks and their complex-valued counterparts. The results demonstrate that the complex-valued network exhibited a better super-resolution performance than its real-valued counterpart and our proposed CVSR-Net achieved the best performance. In addition, the CVSR-Net was tested on out-of-distribution domain datasets and its super-resolution performance was well maintained as compared to that on source domain datasets, indicating a good generalization capability.
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Affiliation(s)
- Lingyun Wang
- School of Electronics and Information Engineering, Soochow University, Suzhou, People's Republic of China
| | - Si Chen
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore
| | - Linbo Liu
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore
| | - Xue Yin
- The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
| | - Guohua Shi
- Jiangsu Key Laboratory of Medical Optics, Suzhou Institute of Biomedical Engineering and Technology, Suzhou, People's Republic of China
| | - Jianhua Mo
- School of Electronics and Information Engineering, Soochow University, Suzhou, People's Republic of China
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4
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Alexopoulos P, Madu C, Wollstein G, Schuman JS. The Development and Clinical Application of Innovative Optical Ophthalmic Imaging Techniques. Front Med (Lausanne) 2022; 9:891369. [PMID: 35847772 PMCID: PMC9279625 DOI: 10.3389/fmed.2022.891369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/23/2022] [Indexed: 11/22/2022] Open
Abstract
The field of ophthalmic imaging has grown substantially over the last years. Massive improvements in image processing and computer hardware have allowed the emergence of multiple imaging techniques of the eye that can transform patient care. The purpose of this review is to describe the most recent advances in eye imaging and explain how new technologies and imaging methods can be utilized in a clinical setting. The introduction of optical coherence tomography (OCT) was a revolution in eye imaging and has since become the standard of care for a plethora of conditions. Its most recent iterations, OCT angiography, and visible light OCT, as well as imaging modalities, such as fluorescent lifetime imaging ophthalmoscopy, would allow a more thorough evaluation of patients and provide additional information on disease processes. Toward that goal, the application of adaptive optics (AO) and full-field scanning to a variety of eye imaging techniques has further allowed the histologic study of single cells in the retina and anterior segment. Toward the goal of remote eye care and more accessible eye imaging, methods such as handheld OCT devices and imaging through smartphones, have emerged. Finally, incorporating artificial intelligence (AI) in eye images has the potential to become a new milestone for eye imaging while also contributing in social aspects of eye care.
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Affiliation(s)
- Palaiologos Alexopoulos
- Department of Ophthalmology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY, United States
| | - Chisom Madu
- Department of Ophthalmology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY, United States
| | - Gadi Wollstein
- Department of Ophthalmology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY, United States
- Department of Biomedical Engineering, NYU Tandon School of Engineering, Brooklyn, NY, United States
- Center for Neural Science, College of Arts & Science, New York University, New York, NY, United States
| | - Joel S. Schuman
- Department of Ophthalmology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY, United States
- Department of Biomedical Engineering, NYU Tandon School of Engineering, Brooklyn, NY, United States
- Center for Neural Science, College of Arts & Science, New York University, New York, NY, United States
- Department of Electrical and Computer Engineering, NYU Tandon School of Engineering, Brooklyn, NY, United States
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5
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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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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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7
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Guo Y, Hormel TT, Pi S, Wei X, Gao M, Morrison JC, Jia Y. An end-to-end network for segmenting the vasculature of three retinal capillary plexuses from OCT angiographic volumes. BIOMEDICAL OPTICS EXPRESS 2021; 12:4889-4900. [PMID: 34513231 PMCID: PMC8407822 DOI: 10.1364/boe.431888] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/28/2021] [Accepted: 07/06/2021] [Indexed: 06/13/2023]
Abstract
The segmentation of en face retinal capillary angiograms from volumetric optical coherence tomographic angiography (OCTA) usually relies on retinal layer segmentation, which is time-consuming and error-prone. In this study, we developed a deep-learning-based method to segment vessels in the superficial vascular plexus (SVP), intermediate capillary plexus (ICP), and deep capillary plexus (DCP) directly from volumetric OCTA data. The method contains a three-dimensional convolutional neural network (CNN) for extracting distinct retinal layers, a custom projection module to generate three vascular plexuses from OCTA data, and three parallel CNNs to segment vasculature. Experimental results on OCTA data from rat eyes demonstrated the feasibility of the proposed method. This end-to-end network has the potential to simplify OCTA data processing on retinal vasculature segmentation. The main contribution of this study is that we propose a custom projection module to connect retinal layer segmentation and vasculature segmentation modules and automatically convert data from three to two dimensions, thus establishing an end-to-end method to segment three retinal capillary plexuses from volumetric OCTA without any human intervention.
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Affiliation(s)
- Yukun Guo
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Tristan T. Hormel
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Shaohua Pi
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Xiang Wei
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR 97239, USA
| | - Min Gao
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - John C. Morrison
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Yali Jia
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR 97239, USA
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8
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Lejoyeux R, Benillouche J, Ong J, Errera MH, Rossi EA, Singh SR, Dansingani KK, da Silva S, Sinha D, Sahel JA, Freund KB, Sadda SR, Lutty GA, Chhablani J. Choriocapillaris: Fundamentals and advancements. Prog Retin Eye Res 2021; 87:100997. [PMID: 34293477 DOI: 10.1016/j.preteyeres.2021.100997] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 07/02/2021] [Accepted: 07/13/2021] [Indexed: 12/19/2022]
Abstract
The choriocapillaris is the innermost structure of the choroid that directly nourishes the retinal pigment epithelium and photoreceptors. This article provides an overview of its hemovasculogenesis development to achieve its final architecture as a lobular vasculature, and also summarizes the current histological and molecular knowledge about choriocapillaris and its dysfunction. After describing the existing state-of-the-art tools to image the choriocapillaris, we report the findings in the choriocapillaris encountered in the most frequent retinochoroidal diseases including vascular diseases, inflammatory diseases, myopia, pachychoroid disease spectrum disorders, and glaucoma. The final section focuses on the development of imaging technology to optimize visualization of the choriocapillaris as well as current treatments of retinochoroidal disorders that specifically target the choriocapillaris. We conclude the article with pertinent unanswered questions and future directions in research for the choriocapillaris.
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Affiliation(s)
| | | | - Joshua Ong
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Marie-Hélène Errera
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Ethan A Rossi
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Department of Bioengineering, University of Pittsburgh Swanson School of Engineering, Pittsburgh, PA 15213, USA
| | - Sumit R Singh
- Jacobs Retina Center, Shiley Eye Institute, University of California San Diego, San Diego, CA, USA
| | - Kunal K Dansingani
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Susana da Silva
- Department of Ophthalmology and Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Debasish Sinha
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Department of Cell Biology and Center for Biologic Imaging, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - José-Alain Sahel
- Rothschild Foundation, 75019, Paris, France; Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France; CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, Paris, France
| | - K Bailey Freund
- LuEsther T. Mertz Retinal Research Center, Manhattan Eye, Ear, and Throat Hospital, New York, NY, USA; Vitreous Retina Macula Consultants of New York, New York, NY, USA; Department of Ophthalmology, New York University of Medicine, New York, NY, USA; Edward S. Harkness Eye Institute, Columbia University Medical Center, New York, NY, USA
| | - SriniVas R Sadda
- Doheny Image Reading Center, Doheny Eye Institute, Los Angeles, CA, 90033, USA; Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Gerard A Lutty
- Wilmer Ophthalmological Institute, Johns Hopkins Hospital, Baltimore, MD, 21287, USA
| | - Jay Chhablani
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
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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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10
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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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11
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Retinal capillary oximetry with visible light optical coherence tomography. Proc Natl Acad Sci U S A 2020; 117:11658-11666. [PMID: 32398376 DOI: 10.1073/pnas.1918546117] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Assessing oxygen saturation (sO2) remains challenging but is nonetheless necessary for understanding retinal metabolism. We and others previously achieved oximetry on major retinal vessels and measured the total retinal oxygen metabolic rate in rats using visible-light optical coherence tomography. Here we extend oximetry measurements to capillaries and investigate all three retinal vascular plexuses by amplifying and extracting the spectroscopic signal from each capillary segment under the guidance of optical coherence tomography (OCT) angiography. Using this approach, we measured capillary sO2 in the retinal circulation in rats, demonstrated reproducibility of the results, validated the measurements in superficial capillaries with known perfusion pathways, and determined sO2 responses to hypoxia and hyperoxia in the different retinal capillary beds. OCT capillary oximetry has the potential to provide new insights into the retinal circulation in the normal eye as well as in retinal vascular diseases.
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12
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Pi S, Hormel TT, Wei X, Cepurna W, Morrison JC, Jia Y. Imaging retinal structures at cellular-level resolution by visible-light optical coherence tomography. OPTICS LETTERS 2020; 45:2107-2110. [PMID: 32236080 PMCID: PMC8575555 DOI: 10.1364/ol.386454] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 03/05/2020] [Indexed: 05/10/2023]
Abstract
In vivo high-resolution images are the most direct way to understand retinal function and diseases. Here we report the use of visible-light optical coherence tomography with volumetric registration and averaging to achieve cellular-level retinal structural imaging in a rat eye, covering the entire depth of the retina. Vitreous fibers, nerve fiber bundles, and vasculature were clearly revealed, as well as at least three laminar sublayers in the inner plexiform layer. We also successfully visualized ganglion cell somas in the ganglion cell layer, cells in the inner nuclear layer, and photoreceptors in the outer nuclear layer and ellipsoid zone. This technique provides, to the best of our knowledge, a new means to visualize the retina in vivo at a cellular resolution and may enable detection or discovery of cellular neuronal biomarkers to help better diagnose ocular disease.
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Affiliation(s)
- Shaohua Pi
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - Tristan T. Hormel
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - Xiang Wei
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - William Cepurna
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - John C. Morrison
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - Yali Jia
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon 97239, USA
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13
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Wang TA, Chan MC, Lee HC, Lee CY, Tsai MT. Ultrahigh-resolution optical coherence tomography/angiography with an economic and compact supercontinuum laser. BIOMEDICAL OPTICS EXPRESS 2019; 10:5687-5702. [PMID: 31799040 PMCID: PMC6865110 DOI: 10.1364/boe.10.005687] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 10/06/2019] [Accepted: 10/07/2019] [Indexed: 05/19/2023]
Abstract
In this study, a Q-switch pumped supercontinuum laser (QS-SCL) is used as a light source for in vivo imaging via ultrahigh-resolution optical coherence tomography and angiography (UHR-OCT/OCTA). For this purpose, an OCT system based on a spectral-domain detection scheme is constructed, and a spectrometer with a spectral range of 635 - 875 nm is designed. The effective full-width at half maximum of spectrum covers 150 nm, and the corresponding axial and transverse resolutions are 2 and 10 µm in air, respectively. The relative intensity noise of the QS-SCL and mode-locked SCL is quantitatively compared. Furthermore, a special processing algorithm is developed to eliminate the intrinsic noise of QS-SCL. This work demonstrates that QS-SCLs can effectively reduce the cost and size of UHR-OCT/OCTA instruments, making clinical applications feasible.
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Affiliation(s)
- Tai-Ang Wang
- Institute of Photonic System, College of Photonics, National Chiao-Tung University, Tainan City 71150, Taiwan
- The authors contributed equally to this work
| | - Ming-Che Chan
- Institute of Photonic System, College of Photonics, National Chiao-Tung University, Tainan City 71150, Taiwan
- The authors contributed equally to this work
| | - Hsiang-Chieh Lee
- Graduate Institute of Photonics and Optoelectronics, National Taiwan University, 10617, Taiwan
- Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Cheng-Yu Lee
- Department of Electrical Engineering, Chang Gung University, Taoyuan 33302, Taiwan
| | - Meng-Tsan Tsai
- Department of Electrical Engineering, Chang Gung University, Taoyuan 33302, Taiwan
- Department of Neurosurgery, Chang Gung Memorial Hospital, Linkou, Taoyuan 33305, Taiwan
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14
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Pi S, Hormel TT, Wei X, Cepurna W, Camino A, Guo Y, Huang D, Morrison J, Jia Y. Monitoring retinal responses to acute intraocular pressure elevation in rats with visible light optical coherence tomography. NEUROPHOTONICS 2019; 6:041104. [PMID: 31312671 PMCID: PMC6624745 DOI: 10.1117/1.nph.6.4.041104] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 06/21/2019] [Indexed: 05/08/2023]
Abstract
Elevated intraocular pressure (IOP) is an important risk factor for glaucoma. However, the role of IOP in glaucoma progression, as well as retinal physiology in general, remains incompletely understood. We demonstrate the use of visible light optical coherence tomography to measure retinal responses to acute IOP elevation in Brown Norway rats. We monitored retinal responses in reflectivity, angiography, blood flow, oxygen saturation ( sO 2 ), and oxygen metabolism over a range of IOP from 10 to 100 mmHg. As IOP was elevated, nerve fiber layer reflectivity was found to decrease. Vascular perfusion in the three retinal capillary plexuses remained steady until IOP exceeded 70 mmHg and arterial flow was noted to reverse periodically at high IOPs. However, a significant drop in total retinal blood flow was observed first at 40 mmHg. As IOP increased, the venous sO 2 demonstrated a gradual decrease despite steady arterial sO 2 , which is consistent with increased arterial-venous oxygen extraction across the retinal capillary beds. Calculated total retinal oxygen metabolism was steady, reflecting balanced responses of blood flow and oxygen extraction, until IOP exceeded 40 mmHg, and fell to 0 at 70 and 80 mmHg. Above this, measurements were unattainable. All measurements reverted to baseline when the IOP was returned to 10 mmHg, indicating good recovery following acute pressure challenge. These results demonstrate the ability of this system to monitor retinal oxygen metabolism noninvasively and how it can help us understand retinal responses to elevated IOP.
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Affiliation(s)
- Shaohua Pi
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Tristan T. Hormel
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Xiang Wei
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - William Cepurna
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Acner Camino
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Yukun Guo
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - David Huang
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - John Morrison
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Yali Jia
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
- Address all correspondence to Yali Jia, E-mail:
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15
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WEI XIANG, CAMINO ACNER, PI SHAOHUA, HORMEL TRISTANT, CEPURNA WILLIAM, HUANG DAVID, MORRISON JOHNC, JIA YALI. Real-time cross-sectional and en face OCT angiography guiding high-quality scan acquisition. OPTICS LETTERS 2019; 44:1431-1434. [PMID: 30874667 PMCID: PMC7188388 DOI: 10.1364/ol.44.001431] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 02/08/2019] [Indexed: 05/18/2023]
Abstract
Defocusing, vignetting, and bulk motion degrade the image quality of optical coherence tomography angiography (OCTA) more significantly than structural OCT. The assessment of focus, alignment conditions, and stability of imaging subjects in commercially available OCTA systems are currently based on OCT signal quality alone, without knowledge of OCTA signal quality. This results in low yield rates for further quantification. In this Letter, we developed a novel OCTA platform based on a graphics processing unit (GPU) for a real-time, high refresh rate, B-san-by-B-scan split-spectrum amplitude-decorrelation angiography. The GPU provides a real-time display of both cross-sectional and en face images to assist operators during scan acquisition and ensure OCTA scan quality.
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16
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Pi S, Camino A, Wei X, Hormel TT, Cepurna W, Morrison JC, Jia Y. Automated phase unwrapping in Doppler optical coherence tomography. JOURNAL OF BIOMEDICAL OPTICS 2019; 24:1-4. [PMID: 30701724 PMCID: PMC6985683 DOI: 10.1117/1.jbo.24.1.010502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 01/21/2019] [Indexed: 05/24/2023]
Abstract
Phase wrapping is a crucial issue in Doppler optical coherence tomography (OCT) and restricts its automatic implementation for clinical applications that quantify total retinal blood flow. We propose an automated phase-unwrapping technique that takes advantage of the parabolic profile of blood flow velocity in vessels. Instead of inspecting the phase shift manually, the algorithm calculates the gradient magnitude of the phase shift on the cross-sectional image and automatically detects the presence of phase wrapping. The voxels affected by phase wrapping are corrected according to the determined flow direction adjacent to the vessel walls. We validated this technique in the rodent retina using a prototype visible-light OCT and in the human retina with a commercial infrared OCT system. We believe this signal processing method may well accelerate clinical applications of Doppler OCT in ophthalmology.
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Affiliation(s)
- Shaohua Pi
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Acner Camino
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Xiang Wei
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Tristan T. Hormel
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - William Cepurna
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - John C. Morrison
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Yali Jia
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
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17
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Chen C, Shi W, Reyes R, Yang VXD. Buffer-averaging super-continuum source based spectral domain optical coherence tomography for high speed imaging. BIOMEDICAL OPTICS EXPRESS 2018; 9:6529-6544. [PMID: 31065447 PMCID: PMC6491018 DOI: 10.1364/boe.9.006529] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 11/15/2018] [Indexed: 06/09/2023]
Abstract
In super-continuum (SC) source based spectral domain optical coherence tomography (SC-SDOCT), the stability of the power spectral density (PSD) has a significant impact on OCT system sensitivity and image signal to noise ratio (SNR). High speed imaging decreases the camera's exposure time, thus each A-scan contained fewer laser pulse excited SC wideband emissions, resulting in a decrease of SNR. In this manuscript, we present a buffer-averaging SC-SDOCT (BASC-SDOCT) to improve the system's performance without losing imaging speed, taking advantage of the excess output power from typical SC sources. In our proposed technique, the output light from SC was passed through a fiber based light buffering and averaging system to improve the PSD stability by averaging 8 SC emissions. The results showed that 6.96 µs of SC emission after buffering and averaging can achieve the same PSD stability equivalent to a longer exposure time of 55.68 µs, despite increasing the imaging speed from 16.8 kHz to 91.9 kHz. The system sensitivity was improved by 8.6 dB, reaching 100.6 dB, which in turn improved SNR of structural imaging, Doppler OCT velocity measurement, and speckle variance OCT (SVOCT) angiographic imaging as demonstrated by phantom and in vivo experiments.
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Affiliation(s)
- Chaoliang Chen
- Biophotonics and Bioengineering Lab, Department of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, Ontario, Canada
| | - Weisong Shi
- Biophotonics and Bioengineering Lab, Department of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, Ontario, Canada
- Department of Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, China
| | - Robnier Reyes
- Biophotonics and Bioengineering Lab, Department of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, Ontario, Canada
| | - Victor X. D. Yang
- Biophotonics and Bioengineering Lab, Department of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, Ontario, Canada
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
- Division of Neurosurgery, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
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18
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Pi S, Camino A, Wei X, Simonett J, Cepurna W, Huang D, Morrison JC, Jia Y. Rodent retinal circulation organization and oxygen metabolism revealed by visible-light optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2018; 9:5851-5862. [PMID: 30460167 PMCID: PMC6238898 DOI: 10.1364/boe.9.005851] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/22/2018] [Accepted: 10/24/2018] [Indexed: 05/06/2023]
Abstract
Visible light optical coherence tomography (vis-OCT) is an emerging label-free and high-resolution 3-dimensional imaging technique that can provide retinal oximetry, angiography, and flowmetry in one modality. In this paper, we studied the organization of the arterial and venous retinal circulation in rats using vis-OCT. Arterioles were found predominantly in the superficial vascular plexus whereas veins tended to drain capillaries from the deep capillary plexus. After that, we determined the oxygen metabolic rate supported by retinal microcirculation by combining retinal vessel oxygen saturation and blood flow measurements. The ability to visualize and monitor retinal circulation organization and oxygen metabolism by vis-OCT may provide new opportunities for understanding the pathology of ocular diseases.
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Affiliation(s)
- Shaohua Pi
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Acner Camino
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Xiang Wei
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Joseph Simonett
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - William Cepurna
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - David Huang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - John C. Morrison
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Yali Jia
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
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19
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Pi S, Camino A, Cepurna W, Wei X, Zhang M, Huang D, Morrison J, Jia Y. Automated spectroscopic retinal oximetry with visible-light optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2018; 9:2056-2067. [PMID: 29760969 PMCID: PMC5946770 DOI: 10.1364/boe.9.002056] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 03/30/2018] [Accepted: 04/01/2018] [Indexed: 05/18/2023]
Abstract
Accurate, quantitative assessment of retinal blood oxygen saturation (sO2 ) may provide a useful early indicator of pathophysiology in several ocular diseases. Here, with visible-light optical coherence tomography (OCT), we demonstrate an automated spectroscopic retinal oximetry algorithm to measure the sO2 within the retinal arteries (A-sO2 ) and veins (V-sO2 ) in rats by automatically detecting the vascular posterior boundary on cross-sectional structural OCT. The algorithm was validated in vitro with flow phantoms and in vivo in rats by comparing the sO2 results, respectively, to those obtained using a blood gas analyzer and pulse oximetry. We also investigated the response of oxygen extraction (A-V sO2 ), including inter-session reproducibility, at different inhaled oxygen concentrations.
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Affiliation(s)
- Shaohua Pi
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Acner Camino
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - William Cepurna
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Xiang Wei
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Miao Zhang
- Optovue Inc. 2800 Bayview Dr., Fremont, CA 94538, USA
| | - David Huang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - John Morrison
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Yali Jia
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
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20
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Wei X, Camino A, Pi S, Cepurna W, Huang D, Morrison JC, Jia Y. Fast and robust standard-deviation-based method for bulk motion compensation in phase-based functional OCT. OPTICS LETTERS 2018; 43:2204-2207. [PMID: 29714790 PMCID: PMC6411296 DOI: 10.1364/ol.43.002204] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Phase-based optical coherence tomography (OCT), such as OCT angiography (OCTA) and Doppler OCT, is sensitive to the confounding phase shift introduced by subject bulk motion. Traditional bulk motion compensation methods are limited by their accuracy and computing cost-effectiveness. In this Letter, to the best of our knowledge, we present a novel bulk motion compensation method for phase-based functional OCT. Bulk motion associated phase shift can be directly derived by solving its equation using a standard deviation of phase-based OCTA and Doppler OCT flow signals. This method was evaluated on rodent retinal images acquired by a prototype visible light OCT and human retinal images acquired by a commercial system. The image quality and computational speed were significantly improved, compared to two conventional phase compensation methods.
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21
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Chong SP, Zhang T, Kho A, Bernucci MT, Dubra A, Srinivasan VJ. Ultrahigh resolution retinal imaging by visible light OCT with longitudinal achromatization. BIOMEDICAL OPTICS EXPRESS 2018; 9:1477-1491. [PMID: 29675296 PMCID: PMC5905900 DOI: 10.1364/boe.9.001477] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 01/30/2018] [Accepted: 02/03/2018] [Indexed: 05/18/2023]
Abstract
Chromatic aberrations are an important design consideration in high resolution, high bandwidth, refractive imaging systems that use visible light. Here, we present a fiber-based spectral/Fourier domain, visible light OCT ophthalmoscope corrected for the average longitudinal chromatic aberration (LCA) of the human eye. Analysis of complex speckles from in vivo retinal images showed that achromatization resulted in a speckle autocorrelation function that was ~20% narrower in the axial direction, but unchanged in the transverse direction. In images from the improved, achromatized system, the separation between Bruch's membrane (BM), the retinal pigment epithelium (RPE), and the outer segment tips clearly emerged across the entire 6.5 mm field-of-view, enabling segmentation and morphometry of BM and the RPE in a human subject. Finally, cross-sectional images depicted distinct inner retinal layers with high resolution. Thus, with chromatic aberration compensation, visible light OCT can achieve volume resolutions and retinal image quality that matches or exceeds ultrahigh resolution near-infrared OCT systems with no monochromatic aberration compensation.
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Affiliation(s)
- Shau Poh Chong
- Biomedical Engineering Department, University of California Davis, Davis, CA 95616, USA
- Equal contributions
| | - Tingwei Zhang
- Biomedical Engineering Department, University of California Davis, Davis, CA 95616, USA
- Equal contributions
| | - Aaron Kho
- Biomedical Engineering Department, University of California Davis, Davis, CA 95616, USA
| | - Marcel T. Bernucci
- Biomedical Engineering Department, University of California Davis, Davis, CA 95616, USA
| | - Alfredo Dubra
- Byers Eye Institute, Stanford University, Palo Alto, CA 94303, USA
| | - Vivek J. Srinivasan
- Biomedical Engineering Department, University of California Davis, Davis, CA 95616, USA
- Department of Ophthalmology and Vision Science, University of California Davis School of Medicine, Sacramento, CA 95817, USA
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