1
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Song J, Hu Y, Chen A, Yoo HS, Zawadzki RJ, Matsubara JA, Ju MJ. In vivo multi-contrast depth-resolved choroidal imaging of a mouse using polarization-diversity optical coherence tomography. OPTICS LETTERS 2024; 49:4314-4317. [PMID: 39090922 DOI: 10.1364/ol.529146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Accepted: 06/27/2024] [Indexed: 08/04/2024]
Abstract
The results of depth-resolved multi-contrast in vivo mouse choroidal imaging using a polarization-diversity optical coherence tomography (PD-OCT) system are presented. A selectively chosen depth of focus that was fine-tuned with a sensorless adaptive optics technique and a simple segmentation based on the degree of polarization uniformity signal visualizes the detailed features of a mouse choroid from the OCT angiography images. A comprehensive image analysis of the choroid revealed the distinctive pathological characteristics of the laser-induced choroidal neovascularization mouse.
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2
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Ni S, Ng R, Huang D, Chen S, Young BK, Peter Campbell J, Jian Y. Non-mydriatic ultra-widefield diffraction-limited retinal imaging. OPTICS LETTERS 2024; 49:3902-3905. [PMID: 39008737 DOI: 10.1364/ol.525364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 06/20/2024] [Indexed: 07/17/2024]
Abstract
We demonstrate a new non-mydriatic ultra-widefield optical coherence tomography retinal imaging system, designed with custom optics to improve the imaging field of view, lateral resolution, and patient comfort. The key motivation is to address the challenge with conventional systems that require pupillary dilation, adding time, expense, discomfort, and medical risk to the examination of the retina. Our system provides an ultrawide 100° field of view (beam scanning angle at the scanning pivot point) and maintains a lateral resolution of 20 µm on the center. It also allows a generous working distance of 16 mm, 2-3 times longer than existing ultra-widefield OCT imaging systems. This advanced system was able to avoid iris vignetting artifacts without pharmacological dilation and ensure diffraction-limited ultra-widefield imaging under a generalized eye model. This enables a comprehensive evaluation of retina diseases, especially those affecting the peripheral regions.
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3
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Brennan BD, Heitkotter H, Carroll J, Tarima S, Cooper RF. Quantifying image quality in AOSLO images of photoreceptors. BIOMEDICAL OPTICS EXPRESS 2024; 15:2849-2862. [PMID: 38855680 PMCID: PMC11161361 DOI: 10.1364/boe.516477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 03/04/2024] [Accepted: 03/05/2024] [Indexed: 06/11/2024]
Abstract
The use of "quality" to describe the usefulness of an image is ubiquitous but is often subject to domain specific constraints. Despite its continued use as an imaging modality, adaptive optics scanning light ophthalmoscopy (AOSLO) lacks a dedicated metric for quantifying the quality of an image of photoreceptors. Here, we present an approach to evaluating image quality that extracts an estimate of the signal to noise ratio. We evaluated its performance in 528 images of photoreceptors from two AOSLOs, two modalities, and healthy or diseased retinas. The algorithm was compared to expert graders' ratings of the images and previously published image quality metrics. We found no significant difference in the SNR and grades across all conditions. The SNR and the grades of the images were moderately correlated. Overall, this algorithm provides an objective measure of image quality that closely relates to expert assessments of quality in both confocal and split-detector AOSLO images of photoreceptors.
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Affiliation(s)
- Brea D. Brennan
- Joint Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Heather Heitkotter
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Joseph Carroll
- Joint Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- Department of Ophthalmology and Visual Science, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Sergey Tarima
- Division of Biostatistics, Institute for Health and Equity, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Robert F. Cooper
- Joint Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- Department of Ophthalmology and Visual Science, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
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4
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Cameron P, Courme B, Vernière C, Pandya R, Faccio D, Defienne H. Adaptive optical imaging with entangled photons. Science 2024; 383:1142-1148. [PMID: 38452085 DOI: 10.1126/science.adk7825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 01/23/2024] [Indexed: 03/09/2024]
Abstract
Adaptive optics (AO) has revolutionized imaging in fields from astronomy to microscopy by correcting optical aberrations. In label-free microscopes, however, conventional AO faces limitations because of the absence of a guide star and the need to select an optimization metric specific to the sample and imaging process. Here, we propose an AO approach leveraging correlations between entangled photons to directly correct the point spread function. This guide star-free method is independent of the specimen and imaging modality. We demonstrate the imaging of biological samples in the presence of aberrations using a bright-field imaging setup operating with a source of spatially entangled photon pairs. Our approach performs better than conventional AO in correcting specific aberrations, particularly those involving substantial defocus. Our work improves AO for label-free microscopy and could play a major role in the development of quantum microscopes.
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Affiliation(s)
- Patrick Cameron
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK
| | - Baptiste Courme
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
- Laboratoire Kastler Brossel, ENS-Universite PSL, CNRS, Sorbonne Universite, College de France, 75005 Paris, France
| | - Chloé Vernière
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
| | - Raj Pandya
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
- Laboratoire Kastler Brossel, ENS-Universite PSL, CNRS, Sorbonne Universite, College de France, 75005 Paris, France
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK
| | - Daniele Faccio
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK
| | - Hugo Defienne
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
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5
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Williams DR, Burns SA, Miller DT, Roorda A. Evolution of adaptive optics retinal imaging [Invited]. BIOMEDICAL OPTICS EXPRESS 2023; 14:1307-1338. [PMID: 36950228 PMCID: PMC10026580 DOI: 10.1364/boe.485371] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 02/02/2023] [Indexed: 05/02/2023]
Abstract
This review describes the progress that has been achieved since adaptive optics (AO) was incorporated into the ophthalmoscope a quarter of a century ago, transforming our ability to image the retina at a cellular spatial scale inside the living eye. The review starts with a comprehensive tabulation of AO papers in the field and then describes the technological advances that have occurred, notably through combining AO with other imaging modalities including confocal, fluorescence, phase contrast, and optical coherence tomography. These advances have made possible many scientific discoveries from the first maps of the topography of the trichromatic cone mosaic to exquisitely sensitive measures of optical and structural changes in photoreceptors in response to light. The future evolution of this technology is poised to offer an increasing array of tools to measure and monitor in vivo retinal structure and function with improved resolution and control.
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Affiliation(s)
- David R. Williams
- The Institute of Optics and the Center for
Visual Science, University of Rochester,
Rochester NY, USA
| | - Stephen A. Burns
- School of Optometry, Indiana
University at Bloomington, Bloomington IN, USA
| | - Donald T. Miller
- School of Optometry, Indiana
University at Bloomington, Bloomington IN, USA
| | - Austin Roorda
- Herbert Wertheim School of Optometry and
Vision Science, University of California at Berkeley, Berkeley CA, USA
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6
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Zhang P, Wahl DJ, Mocci J, Miller EB, Bonora S, Sarunic MV, Zawadzki RJ. Adaptive optics scanning laser ophthalmoscopy and optical coherence tomography (AO-SLO-OCT) system for in vivo mouse retina imaging. BIOMEDICAL OPTICS EXPRESS 2023; 14:299-314. [PMID: 36698677 PMCID: PMC9841993 DOI: 10.1364/boe.473447] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 11/22/2022] [Accepted: 11/22/2022] [Indexed: 05/02/2023]
Abstract
Optical coherence tomography (OCT) and scanning laser ophthalmoscopy (SLO) are imaging technologies invented in the 1980s that have revolutionized the field of in vivo retinal diagnostics and are now commonly used in ophthalmology clinics as well as in vision science research. Adaptive optics (AO) technology enables high-fidelity correction of ocular aberrations, resulting in improved resolution and sensitivity for both SLO and OCT systems. The potential of gathering multi-modal cellular-resolution information in a single instrument is of great interest to the ophthalmic imaging community. Although similar instruments have been developed for imaging the human retina, developing such a system for mice will benefit basic science research and should help with further dissemination of AO technology. Here, we present our work integrating OCT into an existing mouse retinal AO-SLO system, resulting in a multi-modal AO-enhanced imaging system of the living mouse eye. The new system allows either independent or simultaneous data acquisition of AO-SLO and AO-OCT, depending on the requirements of specific scientific experiments. The system allows a data acquisition speed of 200 kHz A-scans/pixel rate for OCT and SLO, respectively. It offers ∼6 µm axial resolution for AO-OCT and a ∼1 µm lateral resolution for AO-SLO-OCT imaging.
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Affiliation(s)
- Pengfei Zhang
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, China
- UC Davis EyePod Small Animals Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA 95616, USA
| | - Daniel J. Wahl
- Engineering Science, Simon Fraser University, Burnaby BC, V5A 1S6, Canada
| | - Jacopo Mocci
- Dynamic Optics srl, Piazza Zanellato 5, 35131, Padova, Italy
| | - Eric B. Miller
- Center for Neuroscience, University of California, Davis, CA 95616, USA
| | - Stefano Bonora
- CNR-Institute for Photonics and Nanotechnology, Via Trasea 7, 35131, Padova, Italy
| | - Marinko V. Sarunic
- Engineering Science, Simon Fraser University, Burnaby BC, V5A 1S6, Canada
- Medical Physics and Biomedical Engineering, University College London, United Kingdom
- Institute of Ophthalmology, University College London, United Kingdom
| | - Robert J. Zawadzki
- UC Davis EyePod Small Animals Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA 95616, USA
- UC Davis Eye Center, Dept. of Ophthalmology & Vision Science, University of California Davis, 4860 Y Street, Suite 2400, Sacramento, California 95817, USA
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7
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Wei X, Hormel TT, Pi S, Wang B, Morrison JC, Jia Y. Wide-field sensorless adaptive optics swept-source optical coherence tomographic angiography in rodents. OPTICS LETTERS 2022; 47:5060-5063. [PMID: 36181186 DOI: 10.1364/ol.472387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 09/04/2022] [Indexed: 06/16/2023]
Abstract
In this study, we present a sensorless adaptive optics swept-source optical coherence tomographic angiography (sAO-SS-OCTA) imaging system for mice. Real-time graphics processing unit (GPU)-based OCTA image acquisition and processing software were applied to guide wavefront correction using a deformable mirror based on signal strength index (SSI) from both OCT and OCTA images. High-resolution OCTA images with aberrations corrected and contrast enhanced were successfully acquired. Fifty-degree field of view high-resolution montaged OCTA images were also acquired.
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8
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Gu B, Zhang Y. Adaptive optics wavefront correction using a damped transpose matrix of the influence function. PHOTONICS RESEARCH 2022; 10:1777-1786. [PMID: 37153536 PMCID: PMC10162714 DOI: 10.1364/prj.452364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
To assess the performance of adaptive optics and predict an optimal wavefront correction, we built a wavefront reconstructor with a damped transpose matrix of the influence function. Using an integral control strategy, we tested this reconstructor with four deformable mirrors in an experimental system, an adaptive optics scanning laser ophthalmoscope, and an adaptive optics near-confocal ophthalmoscope. Testing results proved that this reconstructor could ensure a stable and precise correction for wavefront aberration compared to a conventional optimal reconstructor formed by the inverse matrix of the influence function. This method may provide a helpful tool for testing, evaluating, and optimizing adaptive optics systems.
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Affiliation(s)
- Boyu Gu
- Doheny Eye Institute, 150 N Orange Grove Boulevard, Pasadena, California 91103, USA
- Department of Ophthalmology, University of California - Los Angeles, 100 Stein Plaza Driveway, Los Angeles, CA 90095, USA
| | - Yuhua Zhang
- Doheny Eye Institute, 150 N Orange Grove Boulevard, Pasadena, California 91103, USA
- Department of Ophthalmology, University of California - Los Angeles, 100 Stein Plaza Driveway, Los Angeles, CA 90095, USA
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9
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Zhou K, Wu Z, Zhang T, Li F, Iqbal A, Sivanandam S. Active Aberration Correction with Adaptive Coefficient SPGD Algorithm for Laser Scanning Confocal Microscope. SENSORS (BASEL, SWITZERLAND) 2022; 22:3755. [PMID: 35632164 PMCID: PMC9147356 DOI: 10.3390/s22103755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/02/2022] [Accepted: 05/05/2022] [Indexed: 06/15/2023]
Abstract
A laser scanning confocal microscope (LSCM) is an effective scientific instrument for studying sub-micron structures, and it has been widely used in the field of biological detection. However, the illumination depth of LSCMs is limited due to the optical aberrations introduced by living biological tissue, which acts as an optical medium with a non-uniform refractive index, resulting in a significant dispersion of the focus of LSCM illumination light and, hence, a loss in the resolution of the image. In this study, to minimize the effect of optical aberrations, an image-based adaptive optics technology using an optimized stochastic parallel gradient descent (SPGD) algorithm with an adaptive coefficient is applied to the optical path of an LSCM system. The effectiveness of the proposed aberration correction approach is experimentally evaluated in the LSCM system. The results illustrate that the proposed adaptive optics system with an adaptive coefficient SPGD algorithm can effectively reduce the interference caused by aberrations during depth imaging.
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Affiliation(s)
- Kunhua Zhou
- Department of Precision Mechanical Engineering, Shanghai University, Shanghai 200444, China; (K.Z.); (T.Z.)
| | - Zhizheng Wu
- Department of Precision Mechanical Engineering, Shanghai University, Shanghai 200444, China; (K.Z.); (T.Z.)
| | - Tianyu Zhang
- Department of Precision Mechanical Engineering, Shanghai University, Shanghai 200444, China; (K.Z.); (T.Z.)
| | - Feng Li
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China;
| | - Azhar Iqbal
- Dunlap Institute for Astronomy and Astrophysics, University of Toronto, Toronto, ON M5S 3H4, Canada; (A.I.); (S.S.)
| | - Suresh Sivanandam
- Dunlap Institute for Astronomy and Astrophysics, University of Toronto, Toronto, ON M5S 3H4, Canada; (A.I.); (S.S.)
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10
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Liu S, Xia F, Yang X, Wu M, Bizimana LA, Xu C, Adie SG. Closed-loop wavefront sensing and correction in the mouse brain with computed optical coherence microscopy. BIOMEDICAL OPTICS EXPRESS 2021; 12:4934-4954. [PMID: 34513234 PMCID: PMC8407825 DOI: 10.1364/boe.427979] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/28/2021] [Accepted: 06/29/2021] [Indexed: 05/18/2023]
Abstract
Optical coherence microscopy (OCM) uses interferometric detection to capture the complex optical field with high sensitivity, which enables computational wavefront retrieval using back-scattered light from the sample. Compared to a conventional wavefront sensor, aberration sensing with OCM via computational adaptive optics (CAO) leverages coherence and confocal gating to obtain signals from the focus with less cross-talk from other depths or transverse locations within the field-of-view. Here, we present an investigation of the performance of CAO-based aberration sensing in simulation, bead phantoms, and ex vivo mouse brain tissue. We demonstrate that, due to the influence of the double-pass confocal OCM imaging geometry on the shape of computed pupil functions, computational sensing of high-order aberrations can suffer from signal attenuation in certain spatial-frequency bands and shape similarity with lower order counterparts. However, by sensing and correcting only low-order aberrations (astigmatism, coma, and trefoil), we still successfully corrected tissue-induced aberrations, leading to 3× increase in OCM signal intensity at a depth of ∼0.9 mm in a freshly dissected ex vivo mouse brain.
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Affiliation(s)
- Siyang Liu
- School of Electrical and Computer Engineering, Cornell University, Ithaca, NY 14853, USA
- These authors contribute equally to this work
| | - Fei Xia
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA
- These authors contribute equally to this work
| | - Xusan Yang
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA
| | - Meiqi Wu
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Laurie A. Bizimana
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Chris Xu
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA
| | - Steven G. Adie
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
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11
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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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12
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Knutsson P, Thaung J, Owner-Petersen M, Popović Z. Correction of static and non-common path aberrations in an adaptive optics system using inherent calibration data. OPTICS EXPRESS 2021; 29:3406-3414. [PMID: 33770939 DOI: 10.1364/oe.408954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 12/22/2020] [Indexed: 06/12/2023]
Abstract
For low-order adaptive optics systems, a method that is able to correct for system aberrations in the final focal plane is presented. The paper presents a novel figure of merit, corresponding to the integrated non-normalized tip-tilt-free optical transfer function. The inherent singular value decomposition modal content of the interaction matrix is used to optimize this figure of merit. The method has proven to be stable and robust, providing a simple mean to facilitate diffraction limited imaging in an experimental setup for ophthalmic applications.
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13
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Akyol E, Hagag AM, Sivaprasad S, Lotery AJ. Adaptive optics: principles and applications in ophthalmology. Eye (Lond) 2021; 35:244-264. [PMID: 33257798 PMCID: PMC7852593 DOI: 10.1038/s41433-020-01286-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 10/19/2020] [Accepted: 11/04/2020] [Indexed: 12/26/2022] Open
Abstract
This is a comprehensive review of the principles and applications of adaptive optics (AO) in ophthalmology. It has been combined with flood illumination ophthalmoscopy, scanning laser ophthalmoscopy, as well as optical coherence tomography to image photoreceptors, retinal pigment epithelium (RPE), retinal ganglion cells, lamina cribrosa and the retinal vasculature. In this review, we highlight the clinical studies that have utilised AO to understand disease mechanisms. However, there are some limitations to using AO in a clinical setting including the cost of running an AO imaging service, the time needed to scan patients, the lack of normative databases and the very small size of area imaged. However, it is undoubtedly an exceptional research tool that enables visualisation of the retina at a cellular level.
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Affiliation(s)
- Engin Akyol
- Faculty of Medicine, University of Southampton, Southampton, SO17 1BJ, UK
| | - Ahmed M Hagag
- NIHR Moorfields Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust, London, EC1V 2PD, UK
- UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - Sobha Sivaprasad
- NIHR Moorfields Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust, London, EC1V 2PD, UK
- UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - Andrew J Lotery
- Faculty of Medicine, University of Southampton, Southampton, SO17 1BJ, UK.
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14
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Yoon S, Lee H, Hong JH, Lim YS, Choi W. Laser scanning reflection-matrix microscopy for aberration-free imaging through intact mouse skull. Nat Commun 2020; 11:5721. [PMID: 33184297 PMCID: PMC7665219 DOI: 10.1038/s41467-020-19550-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 10/14/2020] [Indexed: 11/09/2022] Open
Abstract
A mouse skull is a barrier for high-resolution optical imaging because its thick and inhomogeneous internal structures induce complex aberrations varying drastically from position to position. Invasive procedures creating either thinned-skull or open-skull windows are often required for the microscopic imaging of brain tissues underneath. Here, we propose a label-free imaging modality termed laser scanning reflection-matrix microscopy for recording the amplitude and phase maps of reflected waves at non-confocal points as well as confocal points. The proposed method enables us to find and computationally correct up to 10,000 angular modes of aberrations varying at every 10 × 10 µm2 patch in the sample plane. We realized reflectance imaging of myelinated axons in vivo underneath an intact mouse skull, with an ideal diffraction-limited spatial resolution of 450 nm. Furthermore, we demonstrated through-skull two-photon fluorescence imaging of neuronal dendrites and their spines by physically correcting the aberrations identified from the reflection matrix.
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Affiliation(s)
- Seokchan Yoon
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, Seoul, 02841, Korea.,Department of Physics, Korea University, Seoul, 02855, Korea
| | - Hojun Lee
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, Seoul, 02841, Korea.,Department of Physics, Korea University, Seoul, 02855, Korea
| | - Jin Hee Hong
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, Seoul, 02841, Korea.,Department of Physics, Korea University, Seoul, 02855, Korea
| | - Yong-Sik Lim
- Department of Nano Science and Mechanical Engineering and Nanotechnology Research Center, Konkuk University, Chungbuk, Korea
| | - Wonshik Choi
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, Seoul, 02841, Korea. .,Department of Physics, Korea University, Seoul, 02855, Korea.
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15
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Bueno JM, Cruz-Castillo R, Avilés-Trigueros M, Bautista-Elivar N. Arrangement of the photoreceptor mosaic in a diabetic rat model imaged with multiphoton microscopy. BIOMEDICAL OPTICS EXPRESS 2020; 11:4901-4914. [PMID: 33014589 PMCID: PMC7510868 DOI: 10.1364/boe.399835] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 06/11/2023]
Abstract
Diabetic retinopathy (DR) is defined as a microvascular pathology. However, some data have suggested that the retinal photoreceptors (PRs) might be important in the pathogenesis of this ocular disease. In this study the organization of the PRs in control and diabetic-induced rats was compared using multiphoton microscopy. The PR mosaic was imaged at different locations in non-stained retinas. The density of PRs was directly quantified from cell counting. The spatially resolved density presents a double-slope pattern (from the central retina towards the periphery) in both healthy and pathological samples, although the values for the latter were significantly lower all across the retina. Moreover, Voronoi analysis was performed to explore changes in PR topography. In control specimens a hexagonally packed structure was dominant. However, despite the non-controlled effects of the disease in retinal structures, this PR regularity was fairly maintained in diabetic retinas.
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Affiliation(s)
- Juan M. Bueno
- Laboratorio de Óptica, Instituto Universitario de Investigación en Óptica y Nanofísica, Universidad de Murcia, Murcia, Spain
| | - Ricardo Cruz-Castillo
- Área Académica de Matemáticas y Física, Instituto de Ciencias Básicas e Ingeniería, Universidad Autónoma del Estado de Hidalgo, Hidalgo, Mexico
| | - Marcelino Avilés-Trigueros
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia e Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca, “Campus Mare Nostrum” de Excelencia International, Murcia, Spain
| | - Nazario Bautista-Elivar
- Departamento de Ingeniería Eléctrica, Tecnológico Nacional de México, Instituto Tecnológico de Pachuca, Hidalgo, Mexico
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16
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Zhu D, Wang R, Žurauskas M, Pande P, Bi J, Yuan Q, Wang L, Gao Z, Boppart SA. Automated fast computational adaptive optics for optical coherence tomography based on a stochastic parallel gradient descent algorithm. OPTICS EXPRESS 2020; 28:23306-23319. [PMID: 32752329 PMCID: PMC7470677 DOI: 10.1364/oe.395523] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The transverse resolution of optical coherence tomography is decreased by aberrations introduced from optical components and the tested samples. In this paper, an automated fast computational aberration correction method based on a stochastic parallel gradient descent (SPGD) algorithm is proposed for aberration-corrected imaging without adopting extra adaptive optics hardware components. A virtual phase filter constructed through combination of Zernike polynomials is adopted to eliminate the wavefront aberration, and their coefficients are stochastically estimated in parallel through the optimization of the image metrics. The feasibility of the proposed method is validated by a simulated resolution target image, in which the introduced aberration wavefront is estimated accurately and with fast convergence. The computation time for the aberration correction of a 512 × 512 pixel image from 7 terms to 12 terms requires little change, from 2.13 s to 2.35 s. The proposed method is then applied for samples with different scattering properties including a particle-based phantom, ex-vivo rabbit adipose tissue, and in-vivo human retina photoreceptors, respectively. Results indicate that diffraction-limited optical performance is recovered, and the maximum intensity increased nearly 3-fold for out-of-focus plane in particle-based tissue phantom. The SPGD algorithm shows great potential for aberration correction and improved run-time performance compared to our previous Resilient backpropagation (Rprop) algorithm when correcting for complex wavefront distortions. The fast computational aberration correction suggests that after further optimization our method can be integrated for future applications in real-time clinical imaging.
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Affiliation(s)
- Dan Zhu
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Ruoyan Wang
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Mantas Žurauskas
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Paritosh Pande
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Jinci Bi
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Qun Yuan
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Lingjie Wang
- Key Laboratory of Optical System Advanced Manufacturing Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Zhishan Gao
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Stephen A. Boppart
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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17
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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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18
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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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19
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Double Interferometer Design for Independent Wavefront Manipulation in Spectral Domain Optical Coherence Tomography. Sci Rep 2019; 9:14651. [PMID: 31601904 PMCID: PMC6787192 DOI: 10.1038/s41598-019-50996-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 09/23/2019] [Indexed: 11/18/2022] Open
Abstract
Spectral domain optical coherence tomography (SD-OCT) is a highly versatile method which allows for three dimensional optical imaging in scattering media. A number of recent publications demonstrated the technique to benefit from structured illumination and beam shaping approaches, e.g. to enhance the signal-to-noise ratio or the penetration depth with samples such as biological tissue. We present a compact and easy to implement design for independent wavefront manipulation and beam shaping at the reference and sample arm of the interferometric OCT device. The design requires a single spatial light modulator and can be integrated to existing free space SD-OCT systems by modifying the source arm only. We provide analytical and numerical discussion of the presented design as well as experimental data confirming the theoretical analysis. The system is highly versatile and lends itself for applications where independent phase or wavefront control is required. We demonstrate the system to be used for wavefront sensorless adaptive optics as well as for iterative optical wavefront shaping for OCT signal enhancement in strongly scattering media.
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20
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Huang XR, Knighton RW, Spector YZ, Kong W, Qiao J. Temporal change of retinal nerve fiber layer reflectance speckle in normal and hypertensive retinas. Exp Eye Res 2019; 186:107738. [PMID: 31325451 PMCID: PMC6703932 DOI: 10.1016/j.exer.2019.107738] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 06/20/2019] [Accepted: 07/16/2019] [Indexed: 11/29/2022]
Abstract
This study investigated temporal change of retinal nerve fiber layer (RNFL) reflectance speckle in retinas with ocular hypertensive (OHT) damage and in control retinas from untreated eyes. Experimental OHT damage to rat retinas was induced by laser photocoagulation of the trabecular meshwork. A series of 660 nm reflectance images was collected from isolated retinas at 10-sec intervals. Areas containing speckled texture were selected on nerve fiber bundles. Correlation coefficients between images with different imaging delays were calculated and plotted as a function of delay. To evaluate the temporal change of speckles, decay of correlation coefficients with time was fitted with an exponential function characterized by a time constant τ. Reflectance per unit thickness (σ) of the areas was also measured and low σ was used as a surrogate of OHT damage. Speckle phenomena occurred in the control RNFL and the RNFL with reduced σ. In the control retinas, τ and σ were nearly constant along bundles but differed significantly among bundles in the same retinas. Among the control retinas, σ was similar, whereas τ varied significantly. In the retinas with OHT damage (low σ) τ could be within, greater or lower than the range in controls. The parameters τ and σ provide independent assessment of the RNFL with OHT damage. Measurements of temporal change of RNFL reflectance speckle may offer a method for detecting functional abnormality of the RNFL.
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Affiliation(s)
- Xiang-Run Huang
- Bascom Palmer Eye Institute, Miller School of Medicine University of Miami, Miami, FL, USA.
| | - Robert W Knighton
- Bascom Palmer Eye Institute, Miller School of Medicine University of Miami, Miami, FL, USA
| | - Ye Z Spector
- Bascom Palmer Eye Institute, Miller School of Medicine University of Miami, Miami, FL, USA
| | - Wei Kong
- Bascom Palmer Eye Institute, Miller School of Medicine University of Miami, Miami, FL, USA
| | - Jianzhong Qiao
- Bascom Palmer Eye Institute, Miller School of Medicine University of Miami, Miami, FL, USA
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21
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Wahl DJ, Ju MJ, Jian Y, Sarunic MV. Non-invasive cellular-resolution retinal imaging with two-photon excited fluorescence. BIOMEDICAL OPTICS EXPRESS 2019; 10:4859-4873. [PMID: 31565530 PMCID: PMC6757458 DOI: 10.1364/boe.10.004859] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 08/13/2019] [Accepted: 08/13/2019] [Indexed: 05/02/2023]
Abstract
Two-photon excited fluorescence (TPEF) imaging of the retina is a developing technique that provides non-invasive compound-specific measurements from the retina. In this report, we demonstrate high-resolution TPEF imaging of the mouse retina using sensorless adaptive optics (SAO) and optical coherence tomography (OCT). A single near-infrared light source was used for simultaneous multi-modal imaging with OCT and TPEF. The image-based SAO could be performed using the en face OCT or the TPEF for aberration correction. Our results demonstrate OCT and TPEF for angiography. Also, we demonstrate non-invasive cellular-resolution imaging of fluorescently labelled cells and the Retinal Pigment Epithelium (RPE) mosaic.
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Affiliation(s)
- Daniel J. Wahl
- Engineering Science, Simon Fraser University, Burnaby, BC, Canada
| | - Myeong Jin Ju
- Engineering Science, Simon Fraser University, Burnaby, BC, Canada
| | - Yifan Jian
- Engineering Science, Simon Fraser University, Burnaby, BC, Canada
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
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22
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Wahl DJ, Zhang P, Mocci J, Quintavalla M, Muradore R, Jian Y, Bonora S, Sarunic MV, Zawadzki RJ. Adaptive optics in the mouse eye: wavefront sensing based vs. image-guided aberration correction. BIOMEDICAL OPTICS EXPRESS 2019; 10:4757-4774. [PMID: 31565523 PMCID: PMC6757457 DOI: 10.1364/boe.10.004757] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 05/10/2019] [Accepted: 05/11/2019] [Indexed: 05/18/2023]
Abstract
Adaptive Optics (AO) is required to achieve diffraction limited resolution in many real-life imaging applications in biology and medicine. AO is essential to guarantee high fidelity visualization of cellular structures for retinal imaging by correcting ocular aberrations. Aberration correction for mouse retinal imaging by direct wavefront measurement has been demonstrated with great success. However, for mouse eyes, the performance of the wavefront sensor (WFS) based AO can be limited by several factors including non-common path errors, wavefront reconstruction errors, and an ill-defined reference plane. Image-based AO can avoid these issues at the cost of algorithmic execution time. Furthermore, image-based approaches can provide improvements to compactness, accessibility, and even the performance of AO systems. Here, we demonstrate the ability of image-based AO to provide comparable aberration correction and image resolution to the conventional Shack-Hartmann WFS-based AO approach. The residual wavefront error of the mouse eye was monitored during a wavefront sensorless optimization to allow comparison with classical AO. This also allowed us to improve the performance of our AO system for small animal retinal imaging.
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Affiliation(s)
- Daniel J Wahl
- Engineering Science, Simon Fraser University, Burnaby, BC, Canada
- These authors contributed equally
| | - Pengfei Zhang
- Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA, USA
- These authors contributed equally
| | - Jacopo Mocci
- Department of Computer Science, University of Verona, Italy
| | | | | | - Yifan Jian
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Stefano Bonora
- CNR-Institute for Photonics and Nanotechnology, Padova, Italy
| | | | - Robert J Zawadzki
- Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA, USA
- UC Davis Eye Center, Department of Ophthalmology & Vision Science, University of California Davis, Sacramento, CA, USA
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23
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Cunefare D, Huckenpahler AL, Patterson EJ, Dubra A, Carroll J, Farsiu S. RAC-CNN: multimodal deep learning based automatic detection and classification of rod and cone photoreceptors in adaptive optics scanning light ophthalmoscope images. BIOMEDICAL OPTICS EXPRESS 2019; 10:3815-3832. [PMID: 31452977 PMCID: PMC6701534 DOI: 10.1364/boe.10.003815] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/26/2019] [Accepted: 06/29/2019] [Indexed: 05/03/2023]
Abstract
Quantification of the human rod and cone photoreceptor mosaic in adaptive optics scanning light ophthalmoscope (AOSLO) images is useful for the study of various retinal pathologies. Subjective and time-consuming manual grading has remained the gold standard for evaluating these images, with no well validated automatic methods for detecting individual rods having been developed. We present a novel deep learning based automatic method, called the rod and cone CNN (RAC-CNN), for detecting and classifying rods and cones in multimodal AOSLO images. We test our method on images from healthy subjects as well as subjects with achromatopsia over a range of retinal eccentricities. We show that our method is on par with human grading for detecting rods and cones.
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Affiliation(s)
- David Cunefare
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Alison L. Huckenpahler
- Department of Cell Biology, Neurobiology, & Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Emily J. Patterson
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Alfredo Dubra
- Department of Ophthalmology, Stanford University, Palo Alto, CA 94303, USA
| | - Joseph Carroll
- Department of Cell Biology, Neurobiology, & Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Sina Farsiu
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
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24
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Iyer RR, Liu YZ, Boppart SA. Automated sensorless single-shot closed-loop adaptive optics microscopy with feedback from computational adaptive optics. OPTICS EXPRESS 2019; 27:12998-13014. [PMID: 31052832 PMCID: PMC6825599 DOI: 10.1364/oe.27.012998] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 04/02/2019] [Accepted: 04/02/2019] [Indexed: 05/02/2023]
Abstract
Traditional wavefront-sensor-based adaptive optics (AO) techniques face numerous challenges that cause poor performance in scattering samples. Sensorless closed-loop AO techniques overcome these challenges by optimizing an image metric at different states of a deformable mirror (DM). This requires acquisition of a series of images continuously for optimization - an arduous task in dynamic in vivo samples. We present a technique where the different states of the DM are instead simulated using computational adaptive optics (CAO). The optimal wavefront is estimated by performing CAO on an initial volume to minimize an image metric, and then the pattern is translated to the DM. In this paper, we have demonstrated this technique on a spectral-domain optical coherence microscope for three applications: real-time depth-wise aberration correction, single-shot volumetric aberration correction, and extension of depth-of-focus. Our technique overcomes the disadvantages of sensor-based AO, reduces the number of image acquisitions compared to traditional sensorless AO, and retains the advantages of both computational and hardware-based AO.
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Affiliation(s)
- Rishyashring R. Iyer
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
USA
| | - Yuan-Zhi Liu
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
USA
| | - Stephen A. Boppart
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
USA
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
USA
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25
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Gardner MR, Rahman AS, Milner TE, Rylander HG. Scattering-Angle-Resolved Optical Coherence Tomography of a Hypoxic Mouse Retina Model. J Exp Neurosci 2019; 13:1179069519837564. [PMID: 30944521 PMCID: PMC6440039 DOI: 10.1177/1179069519837564] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 02/21/2019] [Indexed: 12/27/2022] Open
Abstract
Several studies have noted a correlation between retinal degeneration and traumatic encephalopathy (TE) making the retina a leading candidate for detection and assessment. Scattering-angle-resolved optical coherence tomography (SAR-OCT) is a candidate imaging modality to detect sub-resolution changes in retinal microstructure. SAR-OCT images of murine retinas that experience a hypoxic insult-euthanasia by isoflurane overdose-are presented. A total of 4 SAR-OCT measurement parameters are reported in 6 longitudinal experiments: blood flow volume fraction, total retinal thickness, reflectance index, and scattering angle. As each mouse expires, blood flow volume fraction decreases, total retinal thickness increases, reflectance index decreases, and scattering angle diversity increases. Contribution of the retinal vasculature to scattering angle diversity is discussed. Results of this study suggest the utility of SAR-OCT to measure TE using scattering angle diversity contrast in the retina.
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Affiliation(s)
- Michael R Gardner
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
- Department of Chemical Engineering, University of Bahrain, Isa Town, Bahrain
| | - Ayesha S Rahman
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Thomas E Milner
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Henry G Rylander
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
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26
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Zhang P, Manna SK, Miller EB, Jian Y, Meleppat RK, Sarunic MV, Pugh EN, Zawadzki RJ. Aperture phase modulation with adaptive optics: a novel approach for speckle reduction and structure extraction in optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2019; 10:552-570. [PMID: 30800499 PMCID: PMC6377907 DOI: 10.1364/boe.10.000552] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 12/19/2018] [Accepted: 12/19/2018] [Indexed: 05/03/2023]
Abstract
Speckle is an inevitable consequence of the use of coherent light in imaging and acts as noise that corrupts image formation in most applications. Optical coherence tomographic imaging, as a technique employing coherence time gating, suffers from speckle. We present here a novel method of suppressing speckle noise intrinsically compatible with adaptive optics (AO) for confocal coherent imaging: modulation of the phase in the system pupil aperture with a segmented deformable mirror (DM) to introduce minor perturbations in the point spread function. This approach creates uncorrelated speckle patterns in a series of images, enabling averaging to suppress speckle noise while maintaining structural detail. A method is presented that efficiently determines the optimal range of modulation of DM segments relative to their AO-optimized position so that speckle noise is reduced while image resolution and signal strength are preserved. The method is active and independent of sample properties. Its effectiveness and efficiency are quantified and demonstrated by both ex vivo non-biological and in vivo biological applications.
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Affiliation(s)
- Pengfei Zhang
- UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, USA
| | - Suman K Manna
- UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, USA
| | - Eric B Miller
- Center for Neuroscience, 1544 Newton Court, University of California Davis, Davis, CA 95618, USA
| | - Yifan Jian
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Ratheesh K Meleppat
- UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, USA
| | - Marinko V Sarunic
- Simon Fraser University, School of Engineering Science, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada
| | - Edward N Pugh
- UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, USA
- UC Davis Eye Center, Dept. of Ophthalmology & Vision Science, University of California Davis, 4860 Y Street, Suite 2400, Sacramento, CA 95817, USA
| | - Robert J Zawadzki
- UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, USA
- UC Davis Eye Center, Dept. of Ophthalmology & Vision Science, University of California Davis, 4860 Y Street, Suite 2400, Sacramento, CA 95817, USA
- Vision Science and Advanced Retinal Imaging Laboratory, Dept. of Ophthalmology & Vision Science, University of California Davis, 4860 Y Street, Suite 2400, Sacramento, CA 95817, USA
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27
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Wahl DJ, Ng R, Ju MJ, Jian Y, Sarunic MV. Sensorless adaptive optics multimodal en-face small animal retinal imaging. BIOMEDICAL OPTICS EXPRESS 2019; 10:252-267. [PMID: 30775098 PMCID: PMC6363194 DOI: 10.1364/boe.10.000252] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/26/2018] [Accepted: 11/27/2018] [Indexed: 05/18/2023]
Abstract
Vision researchers often use small animals due to the availability of many transgenic strains that model human diseases or express biomarkers. Adaptive optics (AO) enables non-invasive single-cell imaging in a living animal but often results in high system complexity. Sensorless AO (SAO) can provide depth-resolved aberration correction with low system complexity. We present a multi-modal sensorless AO en face retina imaging system that includes optical coherence tomography (OCT), OCT-angiography, confocal scanning laser ophthalmoscopy (SLO), and fluorescence detection. We present a compact lens-based imaging system design that allows for a 50-degree maximum field of view (FOV), which can be reduced to the region of interest to perform SAO with the modality of choice. The system performance was demonstrated on wild type mice (C57BL/6J), and transgenic mice with GFP labeled cells. SAO SLO was used for imaging microglia (Cx3cr1-GFP) over ~1 hour, where dynamics of the microglia branches were clearly observed. Our results also include volumetric cellular imaging of microglia throughout the inner retina.
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Affiliation(s)
- Daniel J. Wahl
- Engineering Science, Simon Fraser University, Burnaby, BC, Canada
| | - Ringo Ng
- Engineering Science, Simon Fraser University, Burnaby, BC, Canada
| | - Myeong Jin Ju
- Engineering Science, Simon Fraser University, Burnaby, BC, Canada
| | - Yifan Jian
- Engineering Science, Simon Fraser University, Burnaby, BC, Canada
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
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28
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Goswami M, Wang X, Zhang P, Xiao W, Karlen SJ, Li Y, Zawadzki RJ, Burns ME, Lam KS, Pugh EN. Novel window for cancer nanotheranostics: non-invasive ocular assessments of tumor growth and nanotherapeutic treatment efficacy in vivo. BIOMEDICAL OPTICS EXPRESS 2019; 10:151-166. [PMID: 30775090 PMCID: PMC6363190 DOI: 10.1364/boe.10.000151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/09/2018] [Accepted: 11/10/2018] [Indexed: 05/03/2023]
Abstract
In cancer research there is a fundamental need for animal models that allow the in vivo longitudinal visualization and quantification of tumor development, nanotherapeutic delivery, the tumor microenvironment including blood vessels, macrophages, fibroblasts, immune cells, and extracellular matrix, and the tissue response to treatment. To address this need, we developed a novel mouse ocular xenograft model. Green fluorescent protein (GFP) expressing human glioblastoma cells (between 500 and 10,000) were implanted into the subretinal space of immunodeficient mice (56 eyes). The resultant xenografts were imaged in vivo non-invasively with combined fluorescence scanning laser ophthalmoscopy (SLO) and volumetric optical coherence tomography (OCT) for a period up to several months. Most xenografts exhibited a latent phase followed by a stable or rapidly increasing volume, but about 1/3 underwent spontaneous remission. After prescribed growth, a population of tumors was treated with intravenously delivered doxorubicin-containing porphyrin and cholic acid-based nanoparticles ("nanodox"). Fluorescence resonance energy transfer (FRET) emission (doxorubicin → porphyrin) was used to localize nanodox in the xenografts, and 690 nm light exposure to activate it. Such photo-nanotherapy was highly effective in reducing tumor volume. Histopathology and flow cytometry revealed CD4 + and CD8 + immune cell infiltration of xenografts. Overall, the ocular model shows potential for examining the relationships between neoplastic growth, neovascularization and other features of the immune microenvironment, and for evaluating treatment response longitudinally in vivo.
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Affiliation(s)
- Mayank Goswami
- EyePod Small Animal Ocular Imaging Laboratory, University of California, Davis, CA 95616, USA
- Currently with Department of Physics, Indian Institute of Technology Roorkee, Roorkee, 247667, India
| | - Xinlei Wang
- Department of Cell Biology and Human Anatomy, University of California, Davis, CA 95616, USA
| | - Pengfei Zhang
- EyePod Small Animal Ocular Imaging Laboratory, University of California, Davis, CA 95616, USA
| | - Wenwu Xiao
- Department of Biochemistry and Molecular Medicine and Comprehensive Cancer Center, University of California, Davis, Sacramento, CA 95817, USA
| | - Sarah J Karlen
- Department of Cell Biology and Human Anatomy, University of California, Davis, CA 95616, USA
| | - Yuanpei Li
- Department of Biochemistry and Molecular Medicine and Comprehensive Cancer Center, University of California, Davis, Sacramento, CA 95817, USA
| | - Robert J Zawadzki
- EyePod Small Animal Ocular Imaging Laboratory, University of California, Davis, CA 95616, USA
- Vision Science and Advanced Retinal Imaging Laboratory (VSRI) Department of Ophthalmology and Vision Science, University of California, Davis, CA 95616, USA
| | - Marie E Burns
- Department of Cell Biology and Human Anatomy, University of California, Davis, CA 95616, USA
| | - Kit S Lam
- Department of Biochemistry and Molecular Medicine and Comprehensive Cancer Center, University of California, Davis, Sacramento, CA 95817, USA
| | - Edward N Pugh
- EyePod Small Animal Ocular Imaging Laboratory, University of California, Davis, CA 95616, USA
- Department of Cell Biology and Human Anatomy, University of California, Davis, CA 95616, USA
- Department of Physiology and Membrane Biology, University of California, Davis, CA 95616, USA
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Burns SA, Elsner AE, Sapoznik KA, Warner RL, Gast TJ. Adaptive optics imaging of the human retina. Prog Retin Eye Res 2019; 68:1-30. [PMID: 30165239 PMCID: PMC6347528 DOI: 10.1016/j.preteyeres.2018.08.002] [Citation(s) in RCA: 126] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 08/22/2018] [Accepted: 08/24/2018] [Indexed: 12/18/2022]
Abstract
Adaptive Optics (AO) retinal imaging has provided revolutionary tools to scientists and clinicians for studying retinal structure and function in the living eye. From animal models to clinical patients, AO imaging is changing the way scientists are approaching the study of the retina. By providing cellular and subcellular details without the need for histology, it is now possible to perform large scale studies as well as to understand how an individual retina changes over time. Because AO retinal imaging is non-invasive and when performed with near-IR wavelengths both safe and easily tolerated by patients, it holds promise for being incorporated into clinical trials providing cell specific approaches to monitoring diseases and therapeutic interventions. AO is being used to enhance the ability of OCT, fluorescence imaging, and reflectance imaging. By incorporating imaging that is sensitive to differences in the scattering properties of retinal tissue, it is especially sensitive to disease, which can drastically impact retinal tissue properties. This review examines human AO retinal imaging with a concentration on the use of the Adaptive Optics Scanning Laser Ophthalmoscope (AOSLO). It first covers the background and the overall approaches to human AO retinal imaging, and the technology involved, and then concentrates on using AO retinal imaging to study the structure and function of the retina.
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Affiliation(s)
- Stephen A Burns
- 800E. Atwater S, School of Optometry, Indiana University, Bloomington, IN, United States.
| | - Ann E Elsner
- 800E. Atwater S, School of Optometry, Indiana University, Bloomington, IN, United States
| | - Kaitlyn A Sapoznik
- 800E. Atwater S, School of Optometry, Indiana University, Bloomington, IN, United States
| | - Raymond L Warner
- 800E. Atwater S, School of Optometry, Indiana University, Bloomington, IN, United States
| | - Thomas J Gast
- 800E. Atwater S, School of Optometry, Indiana University, Bloomington, IN, United States
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30
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Design Considerations for Murine Retinal Imaging Using Scattering Angle Resolved Optical Coherence Tomography. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8112159] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Optical coherence tomography (OCT), an optical imaging approach enabling cross-sectional analysis of turbid samples, is routinely used for retinal imaging in human and animal models of diseases affecting the retina. Scattering angle resolved (SAR-)OCT has previously been demonstrated as offering additional contrast in human studies, but no SAR-OCT system has been reported in detail for imaging the retinas of mice. An optical model of a mouse eye was designed and extended for validity at wavelengths of light around 1310 nm; this model was then utilized to develop a SAR-OCT design for murine retinal imaging. A Monte Carlo technique simulates light scattering from the retina, and the simulation results are confirmed with SAR-OCT images. Various images from the SAR-OCT system are presented and utility of the system is described. SAR-OCT is demonstrated as a viable and robust imaging platform to extend utility of retinal OCT imaging by incorporating scattering data into investigative ophthalmologic analysis.
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31
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Ju MJ, Huang C, Wahl DJ, Jian Y, Sarunic MV. Visible light sensorless adaptive optics for retinal structure and fluorescence imaging. OPTICS LETTERS 2018; 43:5162-5165. [PMID: 30320845 DOI: 10.1364/ol.43.005162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Optical coherence tomography (OCT) has emerged as a powerful imaging instrument and technology in biomedicine. OCT imaging is predominantly performed using wavelengths in the near infrared; however, visible light (VIS) has been recently employed in OCT systems with encouraging results for high-resolution retinal imaging. Using a broadband supercontinuum VIS source, we present a sensorless adaptive optics (SAO) multimodal imaging system driven by VIS-OCT for volumetric retinal structural imaging, followed by the acquisition of fluorescence emission. The coherence-gated, depth-resolved VIS-OCT images used for image-guided SAO aberration correction enable high-resolution structural and fluorescence imaging.
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32
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Liu S, Lamont MRE, Mulligan JA, Adie SG. Aberration-diverse optical coherence tomography for suppression of multiple scattering and speckle. BIOMEDICAL OPTICS EXPRESS 2018; 9:4919-4935. [PMID: 30319912 PMCID: PMC6179412 DOI: 10.1364/boe.9.004919] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 09/06/2018] [Accepted: 09/07/2018] [Indexed: 05/05/2023]
Abstract
Multiple scattering is a major barrier that limits the optical imaging depth in scattering media. In order to alleviate this effect, we demonstrate aberration-diverse optical coherence tomography (AD-OCT), which exploits the phase correlation between the deterministic signals from single-scattered photons to suppress the random background caused by multiple scattering and speckle. AD-OCT illuminates the sample volume with diverse aberrated point spread functions, and computationally removes these intentionally applied aberrations. After accumulating 12 astigmatism-diverse OCT volumes, we show a 10 dB enhancement in signal-to-background ratio via a coherent average of reconstructed signals from a USAF target located 7.2 scattering mean free paths below a thick scattering layer, and a 3× speckle contrast reduction from an incoherent average of reconstructed signals inside the scattering layer. This AD-OCT method, when implemented using astigmatic illumination, is a promising approach for ultra-deep volumetric optical coherence microscopy.
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Affiliation(s)
- Siyang Liu
- School of Electrical and Computer Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Michael R. E. Lamont
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Jeffrey A. Mulligan
- School of Electrical and Computer Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Steven G. Adie
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
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33
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Xie D, Li Q, Gao Q, Song W, Zhang HF, Yuan X. In vivo blind-deconvolution photoacoustic ophthalmoscopy with total variation regularization. JOURNAL OF BIOPHOTONICS 2018; 11:e201700360. [PMID: 29577625 DOI: 10.1002/jbio.201700360] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 03/22/2018] [Indexed: 06/08/2023]
Abstract
Photoacoustic ophthalmoscopy (PAOM) is capable of noninvasively imaging anatomic and functional information of the retina in living rodents. However, the strong ocular aberration in rodent eyes and limited ultrasonic detection sensitivity affect PAOM's spatial resolution and signal-to-noise ratio (SNR) in in vivo eyes. In this work, we report a computational approach to combine blind deconvolution (BD) algorithm with a regularizing constraint based on total variation (BDTV) for PAOM imaging restoration. We tested the algorithm in retinal and choroidal microvascular images in albino rat eyes. The algorithm improved PAOM's lateral resolution by around 2-fold. Moreover, it enabled the improvement in imaging SNR for both major vessels and capillaries, and realized the well-preserved blood vessels' edges simultaneously, which surpasses conventional Richardson-Lucy BD algorithm. The reported results indicate that the BDTV algorithm potentially facilitate PAOM in extracting retinal pathophysiological information by enhancing in vivo imaging quality without physically modifying PAOM's optical configuration.
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Affiliation(s)
- Deyan Xie
- State Key Laboratory of Integrated Services Networks, School of Telecommunications Engineering, Xidian University, Xi'an, China
| | - Qin Li
- School of Software Engineering, Shenzhen Institute of Information Technology, Shenzhen, China
| | - Quanxue Gao
- State Key Laboratory of Integrated Services Networks, School of Telecommunications Engineering, Xidian University, Xi'an, China
| | - Wei Song
- Nanophotonics Research Centre, Shenzhen University, Shenzhen, China
| | - Hao F Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois
- Department of Ophthalmology, Northwestern University, Chicago, Illinois
| | - Xiaocong Yuan
- Nanophotonics Research Centre, Shenzhen University, Shenzhen, China
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Liu S, Mulligan JA, Adie SG. Volumetric optical coherence microscopy with a high space-bandwidth- time product enabled by hybrid adaptive optics. BIOMEDICAL OPTICS EXPRESS 2018; 9:3137-3152. [PMID: 29984088 PMCID: PMC6033577 DOI: 10.1364/boe.9.003137] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 05/31/2018] [Accepted: 05/31/2018] [Indexed: 05/06/2023]
Abstract
Optical coherence microscopy (OCM) is a promising modality for high resolution imaging, but has limited ability to capture large-scale volumetric information about dynamic biological processes with cellular resolution. To enhance the throughput of OCM, we implemented a hybrid adaptive optics (hyAO) approach that combines computational adaptive optics with an intentionally aberrated imaging beam generated via hardware adaptive optics. Using hyAO, we demonstrate the depth-equalized illumination and collection ability of an astigmatic beam compared to a Gaussian beam for cellular-resolution imaging. With this advantage, we achieved volumetric OCM with a higher space-bandwidth-time product compared to Gaussian-beam acquisition that employed focus-scanning across depth. HyAO was also used to perform volumetric time-lapse OCM imaging of cellular dynamics over a 1mm × 1mm × 1mm field-of-view with 2 μm isotropic spatial resolution and 3-minute temporal resolution. As hyAO is compatible with both spectral-domain and swept-source beam-scanning OCM systems, significant further improvements in absolute volumetric throughput are possible by use of ultrahigh-speed swept sources.
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Affiliation(s)
- Siyang Liu
- School of Electrical and Computer Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Jeffrey A. Mulligan
- School of Electrical and Computer Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Steven G. Adie
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
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35
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Sredar N, Fagbemi OE, Dubra A. Sub-Airy Confocal Adaptive Optics Scanning Ophthalmoscopy. Transl Vis Sci Technol 2018; 7:17. [PMID: 29629239 PMCID: PMC5886094 DOI: 10.1167/tvst.7.2.17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 02/18/2018] [Indexed: 11/24/2022] Open
Abstract
Purpose To demonstrate the viability of improving transverse image resolution in reflectance scanning adaptive optics ophthalmoscopy using sub-Airy disk confocal detection. Methods The foveal cone mosaic was imaged in five human subjects free of known eye disease using two custom adaptive optics scanning light ophthalmoscopes (AOSLOs) in reflectance with 7.75 and 4.30 mm pupil diameters. Confocal pinholes of 0.5, 0.6, 0.8, and 1.0 Airy disk diameters (ADDs) were used in a retinal conjugate plane before the light detector. Average cone photoreceptor intensity profile width and power spectrum were calculated for the resulting images. Detected energy using a model eye was recorded for each pinhole size. Results The cone photoreceptor mosaic is better resolved with decreasing confocal pinhole size, with the high spatial frequency content of the images enhanced in both the large- and small-pupil AOSLOs. The average cone intensity profile width was reduced by ∼15% with the use of a 0.5 ADD pinhole when compared to a 1.0 ADD, with an accompanying reduction in signal greater than a factor of four. Conclusions The use of sub-Airy disk confocal pinhole detection without increasing retinal light exposure results in a substantial improvement in image resolution at the cost of larger than predicted signal reduction. Translational Relevance Improvement in transverse resolution using sub-Airy disk confocal detection is a practical and low-cost approach that is applicable to all point- and line-scanning ophthalmoscopes, including optical coherence tomographers.
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Affiliation(s)
- Nripun Sredar
- Byers Eye Institute, Stanford University, Palo Alto, CA, USA
| | | | - Alfredo Dubra
- Byers Eye Institute, Stanford University, Palo Alto, CA, USA
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36
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Zhang P, Mocci J, Wahl DJ, Meleppat RK, Manna SK, Quintavalla M, Muradore R, Sarunic MV, Bonora S, Pugh EN, Zawadzki RJ. Effect of a contact lens on mouse retinal in vivo imaging: Effective focal length changes and monochromatic aberrations. Exp Eye Res 2018; 172:86-93. [PMID: 29604280 PMCID: PMC6417837 DOI: 10.1016/j.exer.2018.03.027] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 02/26/2018] [Accepted: 03/27/2018] [Indexed: 01/09/2023]
Abstract
For in vivo mouse retinal imaging, especially with Adaptive Optics instruments, application of a contact lens is desirable, as it allows maintenance of cornea hydration and helps to prevent cataract formation during lengthy imaging sessions. However, since the refractive elements of the eye (cornea and lens) serve as the objective for most in vivo retinal imaging systems, the use of a contact lens, even with 0 Dpt. refractive power, can alter the system’s optical properties. In this investigation we examined the effective focal length change and the aberrations that arise from use of a contact lens. First, focal length changes were simulated with a Zemax mouse eye model. Then ocular aberrations with and without a 0 Dpt. contact lens were measured with a Shack-Hartmann wavefront sensor (SHWS) in a customized AO-SLO system. Total RMS wavefront errors were measured for two groups of mice (14-month, and 2.5-month-old), decomposed into 66 Zernike aberration terms, and compared. These data revealed that vertical coma and spherical aberrations were increased with use of a contact lens in our system. Based on the ocular wavefront data we evaluated the effect of the contact lens on the imaging system performance as a function of the pupil size. Both RMS error and Strehl ratios were quantified for the two groups of mice, with and without contact lenses, and for different input beam sizes. These results provide information for determining optimum pupil size for retinal imaging without adaptive optics, and raise critical issues for design of mouse optical imaging systems that incorporate contact lenses.
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Affiliation(s)
- Pengfei Zhang
- UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, United States
| | - Jacopo Mocci
- CNR-Institute for Photonics and Nanotechnology, Via Trasea 7, 35131, Padova, Italy
| | - Daniel J Wahl
- Engineering Science, Simon Fraser University, Burnaby BC, V5A 1S6, Canada
| | - Ratheesh Kumar Meleppat
- UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, United States
| | - Suman K Manna
- UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, United States
| | - Martino Quintavalla
- CNR-Institute for Photonics and Nanotechnology, Via Trasea 7, 35131, Padova, Italy
| | | | - Marinko V Sarunic
- Engineering Science, Simon Fraser University, Burnaby BC, V5A 1S6, Canada
| | - Stefano Bonora
- CNR-Institute for Photonics and Nanotechnology, Via Trasea 7, 35131, Padova, Italy
| | - Edward N Pugh
- UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, United States; UC Davis Eye Center, Dept. of Ophthalmology & Vision Science, University of California Davis, 4860 Y Street, Suite 2400, Sacramento, CA 95817, United States
| | - Robert J Zawadzki
- UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, United States; UC Davis Eye Center, Dept. of Ophthalmology & Vision Science, University of California Davis, 4860 Y Street, Suite 2400, Sacramento, CA 95817, United States.
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37
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Ju MJ, Heisler M, Wahl D, Jian Y, Sarunic MV. Multiscale sensorless adaptive optics OCT angiography system for in vivo human retinal imaging. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:1-10. [PMID: 29094524 DOI: 10.1117/1.jbo.22.12.121703] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 10/05/2017] [Indexed: 05/25/2023]
Abstract
We present a multiscale sensorless adaptive optics (SAO) OCT system capable of imaging retinal structure and vasculature with various fields-of-view (FOV) and resolutions. Using a single deformable mirror and exploiting the polarization properties of light, the SAO-OCT-A was implemented in a compact and easy to operate system. With the ability to adjust the beam diameter at the pupil, retinal imaging was demonstrated at two different numerical apertures with the same system. The general morphological structure and retinal vasculature could be observed with a few tens of micrometer-scale lateral resolution with conventional OCT and OCT-A scanning protocols with a 1.7-mm-diameter beam incident at the pupil and a large FOV (15 deg× 15 deg). Changing the system to a higher numerical aperture with a 5.0-mm-diameter beam incident at the pupil and the SAO aberration correction, the FOV was reduced to 3 deg× 3 deg for fine detailed imaging of morphological structure and microvasculature such as the photoreceptor mosaic and capillaries. Multiscale functional SAO-OCT imaging was performed on four healthy subjects, demonstrating its functionality and potential for clinical utility.
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Affiliation(s)
- Myeong Jin Ju
- Simon Fraser University, Department of Engineering Science, Burnaby, British Columbia, Canada
| | - Morgan Heisler
- Simon Fraser University, Department of Engineering Science, Burnaby, British Columbia, Canada
| | - Daniel Wahl
- Simon Fraser University, Department of Engineering Science, Burnaby, British Columbia, Canada
| | - Yifan Jian
- Simon Fraser University, Department of Engineering Science, Burnaby, British Columbia, Canada
| | - Marinko V Sarunic
- Simon Fraser University, Department of Engineering Science, Burnaby, British Columbia, Canada
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38
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Pircher M, Zawadzki RJ. Review of adaptive optics OCT (AO-OCT): principles and applications for retinal imaging [Invited]. BIOMEDICAL OPTICS EXPRESS 2017; 8:2536-2562. [PMID: 28663890 PMCID: PMC5480497 DOI: 10.1364/boe.8.002536] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 04/08/2017] [Accepted: 04/09/2017] [Indexed: 05/17/2023]
Abstract
In vivo imaging of the human retina with a resolution that allows visualization of cellular structures has proven to be essential to broaden our knowledge about the physiology of this precious and very complex neural tissue that enables the first steps in vision. Many pathologic changes originate from functional and structural alterations on a cellular scale, long before any degradation in vision can be noted. Therefore, it is important to investigate these tissues with a sufficient level of detail in order to better understand associated disease development or the effects of therapeutic intervention. Optical retinal imaging modalities rely on the optical elements of the eye itself (mainly the cornea and lens) to produce retinal images and are therefore affected by the specific arrangement of these elements and possible imperfections in curvature. Thus, aberrations are introduced to the imaging light and image quality is degraded. To compensate for these aberrations, adaptive optics (AO), a technology initially developed in astronomy, has been utilized. However, the axial sectioning provided by retinal AO-based fundus cameras and scanning laser ophthalmoscope instruments is limited to tens of micrometers because of the rather small available numerical aperture of the eye. To overcome this limitation and thus achieve much higher axial sectioning in the order of 2-5µm, AO has been combined with optical coherence tomography (OCT) into AO-OCT. This enabled for the first time in vivo volumetric retinal imaging with high isotropic resolution. This article summarizes the technical aspects of AO-OCT and provides an overview on its various implementations and some of its clinical applications. In addition, latest developments in the field, such as computational AO-OCT and wavefront sensor less AO-OCT, are covered.
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Affiliation(s)
- Michael Pircher
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20/4L, 1090 Vienna, Austria
| | - Robert J Zawadzki
- UC Davis RISE Eye-Pod Laboratory, Dept. of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, USA
- Vision Science and Advanced Retinal Imaging Laboratory (VSRI) and Department of Ophthalmology and Vision Science, UC Davis, 4860 Y Street, Ste. 2400, Sacramento, CA 95817, USA
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Verstraete HRGW, Heisler M, Ju MJ, Wahl D, Bliek L, Kalkman J, Bonora S, Jian Y, Verhaegen M, Sarunic MV. Wavefront sensorless adaptive optics OCT with the DONE algorithm for in vivo human retinal imaging [Invited]. BIOMEDICAL OPTICS EXPRESS 2017; 8:2261-2275. [PMID: 28736670 PMCID: PMC5516811 DOI: 10.1364/boe.8.002261] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 03/07/2017] [Accepted: 03/12/2017] [Indexed: 05/05/2023]
Abstract
In this report, which is an international collaboration of OCT, adaptive optics, and control research, we demonstrate the Data-based Online Nonlinear Extremum-seeker (DONE) algorithm to guide the image based optimization for wavefront sensorless adaptive optics (WFSL-AO) OCT for in vivo human retinal imaging. The ocular aberrations were corrected using a multi-actuator adaptive lens after linearization of the hysteresis in the piezoelectric actuators. The DONE algorithm succeeded in drastically improving image quality and the OCT signal intensity, up to a factor seven, while achieving a computational time of 1 ms per iteration, making it applicable for many high speed applications. We demonstrate the correction of five aberrations using 70 iterations of the DONE algorithm performed over 2.8 s of continuous volumetric OCT acquisition. Data acquired from an imaging phantom and in vivo from human research volunteers are presented.
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Affiliation(s)
- Hans R. G. W. Verstraete
- Delft Center for Systems and Control, Delft University of Technology, Mekelweg 2, 2628 CD, Delft, The
Netherlands
| | - Morgan Heisler
- School of Engineering Science, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6,
Canada
| | - Myeong Jin Ju
- School of Engineering Science, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6,
Canada
| | - Daniel Wahl
- School of Engineering Science, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6,
Canada
| | - Laurens Bliek
- Delft Center for Systems and Control, Delft University of Technology, Mekelweg 2, 2628 CD, Delft, The
Netherlands
| | - Jeroen Kalkman
- Department of Imaging Physics, Delft University of Technology, Lorentzweg 1, 2628 CJ, Delft, The
Netherlands
| | - Stefano Bonora
- Department of Imaging Physics, Delft University of Technology, Lorentzweg 1, 2628 CJ, Delft, The
Netherlands
| | - Yifan Jian
- School of Engineering Science, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6,
Canada
- These authors contributed equally
| | - Michel Verhaegen
- Delft Center for Systems and Control, Delft University of Technology, Mekelweg 2, 2628 CD, Delft, The
Netherlands
- These authors contributed equally
| | - Marinko V. Sarunic
- School of Engineering Science, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6,
Canada
- These authors contributed equally
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40
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Wahl DJ, Huang C, Bonora S, Jian Y, Sarunic MV. Pupil segmentation adaptive optics for invivo mouse retinal fluorescence imaging. OPTICS LETTERS 2017; 42:1365-1368. [PMID: 28362770 DOI: 10.1364/ol.42.001365] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Adaptive Optics (AO) for scanning laser ophthalmoscopy enables high-resolution retinal imaging that can be used for preclinical research of diseases causing vision loss. Pupil Segmentation (PS) is an approach to wavefront-sensorless AO that acquires images within subregions across the imaging pupil to measure the wavefront slopes at the corresponding locations of the beam. We present PS-AO as an approach to correct ocular aberrations in ∼7 s, implemented to minimize respiratory motion from an anesthetized mouse. We demonstrated an improvement in resolution and an image intensity increase of ∼25% across all results using PS-AO for in vivo fluorescence retinal imaging in mice using a MEMS-based segmented deformable mirror.
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41
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Reddikumar M, Tanabe A, Hashimoto N, Cense B. Optical coherence tomography with a 2.8-mm beam diameter and sensorless defocus and astigmatism correction. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:26005. [PMID: 28195602 DOI: 10.1117/1.jbo.22.2.026005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 01/23/2017] [Indexed: 05/02/2023]
Abstract
An optical coherence tomography (OCT) system with a 2.8-mm beam diameter is presented. Sensorless defocus correction can be performed with a Badal optometer and astigmatism correction with a liquid crystal device. OCT B-scans were used in an image-based optimization algorithm for aberration correction. Defocus can be corrected from ? 4.3 ?? D to + 4.3 ?? D and vertical and oblique astigmatism from ? 2.5 ?? D to + 2.5 ?? D . A contrast gain of 6.9 times was measured after aberration correction. In comparison with a 1.3-mm beam diameter OCT system, this concept achieved a 3.7-dB gain in dynamic range on a model retina. Both systems were used to image the retina of a human subject. As the correction of the liquid crystal device can take more than 60 s, the subject’s spectacle prescription was adopted instead. This resulted in a 2.5 times smaller speckle size compared with the standard OCT system. The liquid crystal device for astigmatism correction does not need a high-voltage amplifier and can be operated at 5 V. The correction device is small ( 9 ?? mm × 30 ?? mm × 38 ?? mm ) and can easily be implemented in existing designs for OCT.
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Affiliation(s)
- Maddipatla Reddikumar
- Utsunomiya University, Center for Optical Research and Education, Utsunomiya, Tochigi, Japan
| | - Ayano Tanabe
- Citizen Holding, Development Department, Tokorozawa, Saitama, Japan
| | | | - Barry Cense
- Utsunomiya University, Center for Optical Research and Education, Utsunomiya, Tochigi, Japan
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42
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Polans J, Cunefare D, Cole E, Keller B, Mettu PS, Cousins SW, Allingham MJ, Izatt JA, Farsiu S. Enhanced visualization of peripheral retinal vasculature with wavefront sensorless adaptive optics optical coherence tomography angiography in diabetic patients. OPTICS LETTERS 2017; 42:17-20. [PMID: 28059209 PMCID: PMC5510471 DOI: 10.1364/ol.42.000017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Optical coherence tomography angiography (OCTA) is a promising technique for non-invasive visualization of vessel networks in the human eye. We debut a system capable of acquiring wide field-of-view (>70°) OCT angiograms without mosaicking. Additionally, we report on enhancing the visualization of peripheral microvasculature using wavefront sensorless adaptive optics (WSAO). We employed a fast WSAO algorithm that enabled wavefront correction in <2 s by iterating the mirror shape at the speed of OCT B-scans rather than volumes. Also, we contrasted ∼7° field-of-view OCTA angiograms acquired in the periphery with and without WSAO correction. On average, WSAO improved the sharpness of microvasculature by 65% in healthy eyes and 38% in diseased eyes. Preliminary observations demonstrated that the location of 7° images could be identified directly from the wide field-of-view angiogram. A pilot study on a normal subject and patients with diabetic retinopathy showed the impact of utilizing WSAO for OCTA when visualizing peripheral vasculature pathologies.
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Affiliation(s)
- James Polans
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
- Corresponding author:
| | - David Cunefare
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
| | - Eli Cole
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
| | - Brenton Keller
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
| | - Priyatham S. Mettu
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Scott W. Cousins
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Michael J. Allingham
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Joseph A. Izatt
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Sina Farsiu
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710, USA
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Polans J, Keller B, Carrasco-Zevallos OM, LaRocca F, Cole E, Whitson HE, Lad EM, Farsiu S, Izatt JA. Wide-field retinal optical coherence tomography with wavefront sensorless adaptive optics for enhanced imaging of targeted regions. BIOMEDICAL OPTICS EXPRESS 2017; 8:16-37. [PMID: 28101398 PMCID: PMC5231289 DOI: 10.1364/boe.8.000016] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 10/28/2016] [Accepted: 11/19/2016] [Indexed: 05/03/2023]
Abstract
The peripheral retina of the human eye offers a unique opportunity for assessment and monitoring of ocular diseases. We have developed a novel wide-field (>70°) optical coherence tomography system (WF-OCT) equipped with wavefront sensorless adaptive optics (WSAO) for enhancing the visualization of smaller (<25°) targeted regions in the peripheral retina. We iterated the WSAO algorithm at the speed of individual OCT B-scans (~20 ms) by using raw spectral interferograms to calculate the optimization metric. Our WSAO approach with a 3 mm beam diameter permitted primarily low- but also high- order peripheral wavefront correction in less than 10 seconds. In preliminary imaging studies in five normal human subjects, we quantified statistically significant changes with WSAO correction, corresponding to a 10.4% improvement in average pixel brightness (signal) and 7.0% improvement in high frequency content (resolution) when visualizing 1 mm (~3.5°) B-scans of the peripheral (>23°) retina. We demonstrated the ability of our WF-OCT system to acquire non wavefront-corrected wide-field images rapidly, which could then be used to locate regions of interest, zoom into targeted features, and visualize the same region at different time points. A pilot clinical study was conducted on seven healthy volunteers and two subjects with prodromal Alzheimer's disease which illustrated the capability to image Drusen-like pathologies as far as 32.5° from the fovea in un-averaged volume scans. This work suggests that the proposed combination of WF-OCT and WSAO may find applications in the diagnosis and treatment of ocular, and potentially neurodegenerative, diseases of the peripheral retina, including diabetes and Alzheimer's disease.
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Affiliation(s)
- James Polans
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
| | - Brenton Keller
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
| | - Oscar M. Carrasco-Zevallos
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
| | - Francesco LaRocca
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
| | - Elijah Cole
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
| | - Heather E. Whitson
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710, USA
- Department of Medicine (Geriatrics)/Duke Aging Center, Duke University Medical Center, Durham, North Carolina 27710, USA
- Geriatrics Research Education & Clinical Center, Durham VA Medical Center, Durham, North Carolina 27705, USA
| | - Eleonora M. Lad
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Sina Farsiu
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Joseph A. Izatt
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, North Carolina 27708, USA
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710, USA
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Yu H, Lee P, Jo Y, Lee K, Tuchin VV, Jeong Y, Park Y. Collaborative effects of wavefront shaping and optical clearing agent in optical coherence tomography. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:121510. [PMID: 27792807 DOI: 10.1117/1.jbo.21.12.121510] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 10/05/2016] [Indexed: 06/06/2023]
Abstract
We demonstrate that simultaneous application of optical clearing agents (OCAs) and complex wavefront shaping in optical coherence tomography (OCT) can provide significant enhancement of penetration depth and imaging quality. OCA reduces optical inhomogeneity of a highly scattering sample, and the wavefront shaping of illumination light controls multiple scattering, resulting in an enhancement of the penetration depth and signal-to-noise ratio. A tissue phantom study shows that concurrent applications of OCA and wavefront shaping successfully operate in OCT imaging. The penetration depth enhancement is further demonstrated for <italic<ex vivo</italic< mouse ears, revealing hidden structures inaccessible with conventional OCT imaging.
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Affiliation(s)
- Hyeonseung Yu
- Korea Advanced Institute of Science and Technology, Department of Physics, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of KoreabKAIST Institute of Health Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Peter Lee
- KAIST Institute of Health Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of KoreacKorea Advanced Institute of Science and Technology, Department of Bio and Brain Engineering, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - YoungJu Jo
- Korea Advanced Institute of Science and Technology, Department of Physics, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of KoreabKAIST Institute of Health Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - KyeoReh Lee
- Korea Advanced Institute of Science and Technology, Department of Physics, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of KoreabKAIST Institute of Health Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Valery V Tuchin
- Saratov National Research State University, Research-Education Institute of Optics and Biophotonics, 83, Astrakhanskaya Street, Saratov 410012, RussiaeInstitute of Precision Mechanics and Control of Russian Academy of Sciences, Laboratory of Laser Diagnostics of Technical and Living Systems, 24, Rabochaya Street, Saratov 410028, RussiafNational Research Tomsk State University, Laboratory of Biophotonics, 36, Lenin's Avenue, Tomsk 634050, Russia
| | - Yong Jeong
- KAIST Institute of Health Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of KoreacKorea Advanced Institute of Science and Technology, Department of Bio and Brain Engineering, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - YongKeun Park
- Korea Advanced Institute of Science and Technology, Department of Physics, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of KoreabKAIST Institute of Health Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
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Cua M, Wahl DJ, Zhao Y, Lee S, Bonora S, Zawadzki RJ, Jian Y, Sarunic MV. Coherence-Gated Sensorless Adaptive Optics Multiphoton Retinal Imaging. Sci Rep 2016; 6:32223. [PMID: 27599635 PMCID: PMC5013266 DOI: 10.1038/srep32223] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 08/04/2016] [Indexed: 11/09/2022] Open
Abstract
Multiphoton microscopy enables imaging deep into scattering tissues. The efficient generation of non-linear optical effects is related to both the pulse duration (typically on the order of femtoseconds) and the size of the focused spot. Aberrations introduced by refractive index inhomogeneity in the sample distort the wavefront and enlarge the focal spot, which reduces the multiphoton signal. Traditional approaches to adaptive optics wavefront correction are not effective in thick or multi-layered scattering media. In this report, we present sensorless adaptive optics (SAO) using low-coherence interferometric detection of the excitation light for depth-resolved aberration correction of two-photon excited fluorescence (TPEF) in biological tissue. We demonstrate coherence-gated SAO TPEF using a transmissive multi-actuator adaptive lens for in vivo imaging in a mouse retina. This configuration has significant potential for reducing the laser power required for adaptive optics multiphoton imaging, and for facilitating integration with existing systems.
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Affiliation(s)
- Michelle Cua
- School of Engineering Science, Simon Fraser University, Burnaby, BC V5A 1S6 Canada
| | - Daniel J Wahl
- School of Engineering Science, Simon Fraser University, Burnaby, BC V5A 1S6 Canada
| | - Yuan Zhao
- School of Engineering Science, Simon Fraser University, Burnaby, BC V5A 1S6 Canada
| | - Sujin Lee
- School of Engineering Science, Simon Fraser University, Burnaby, BC V5A 1S6 Canada
| | - Stefano Bonora
- CNR-Institute for Photonics and Nanotechnology, Via Trasea 7, 35131, Padova, Italy
| | - Robert J Zawadzki
- UC Davis RISE Small Animal Ocular Imaging Facility, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA 95616, USA.,Vision Science and Advanced Retinal Imaging laboratory (VSRI), Department of Ophthalmology &Vision Science, University of California Davis, Sacramento, CA 95817 USA
| | - Yifan Jian
- School of Engineering Science, Simon Fraser University, Burnaby, BC V5A 1S6 Canada
| | - Marinko V Sarunic
- School of Engineering Science, Simon Fraser University, Burnaby, BC V5A 1S6 Canada
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46
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Pande P, Liu YZ, South FA, Boppart SA. Automated computational aberration correction method for broadband interferometric imaging techniques. OPTICS LETTERS 2016; 41:3324-7. [PMID: 27420526 PMCID: PMC5458773 DOI: 10.1364/ol.41.003324] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Numerical correction of optical aberrations provides an inexpensive and simpler alternative to the traditionally used hardware-based adaptive optics techniques. In this Letter, we present an automated computational aberration correction method for broadband interferometric imaging techniques. In the proposed method, the process of aberration correction is modeled as a filtering operation on the aberrant image using a phase filter in the Fourier domain. The phase filter is expressed as a linear combination of Zernike polynomials with unknown coefficients, which are estimated through an iterative optimization scheme based on maximizing an image sharpness metric. The method is validated on both simulated data and experimental data obtained from a tissue phantom, an ex vivo tissue sample, and an in vivo photoreceptor layer of the human retina.
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Affiliation(s)
- Paritosh Pande
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Yuan-Zhi Liu
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Fredrick A. South
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Stephen A. Boppart
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Corresponding author:
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Jonnal RS, Kocaoglu OP, Zawadzki RJ, Liu Z, Miller DT, Werner JS. A Review of Adaptive Optics Optical Coherence Tomography: Technical Advances, Scientific Applications, and the Future. Invest Ophthalmol Vis Sci 2016; 57:OCT51-68. [PMID: 27409507 PMCID: PMC4968917 DOI: 10.1167/iovs.16-19103] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 05/29/2016] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Optical coherence tomography (OCT) has enabled "virtual biopsy" of the living human retina, revolutionizing both basic retina research and clinical practice over the past 25 years. For most of those years, in parallel, adaptive optics (AO) has been used to improve the transverse resolution of ophthalmoscopes to foster in vivo study of the retina at the microscopic level. Here, we review work done over the last 15 years to combine the microscopic transverse resolution of AO with the microscopic axial resolution of OCT, building AO-OCT systems with the highest three-dimensional resolution of any existing retinal imaging modality. METHODS We surveyed the literature to identify the most influential antecedent work, important milestones in the development of AO-OCT technology, its applications that have yielded new knowledge, research areas into which it may productively expand, and nascent applications that have the potential to grow. RESULTS Initial efforts focused on demonstrating three-dimensional resolution. Since then, many improvements have been made in resolution and speed, as well as other enhancements of acquisition and postprocessing techniques. Progress on these fronts has produced numerous discoveries about the anatomy, function, and optical properties of the retina. CONCLUSIONS Adaptive optics OCT continues to evolve technically and to contribute to our basic and clinical knowledge of the retina. Due to its capacity to reveal cellular and microscopic detail invisible to clinical OCT systems, it is an ideal companion to those instruments and has the demonstrable potential to produce images that can guide the interpretation of clinical findings.
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Affiliation(s)
- Ravi S. Jonnal
- Vision Science and Advanced Retinal Imaging Laboratory University of California-Davis, Sacramento, California, United States
| | - Omer P. Kocaoglu
- School of Optometry, Indiana University, Bloomington, Indiana, United States
| | - Robert J. Zawadzki
- Vision Science and Advanced Retinal Imaging Laboratory University of California-Davis, Sacramento, California, United States
| | - Zhuolin Liu
- School of Optometry, Indiana University, Bloomington, Indiana, United States
| | - Donald T. Miller
- School of Optometry, Indiana University, Bloomington, Indiana, United States
| | - John S. Werner
- Vision Science and Advanced Retinal Imaging Laboratory University of California-Davis, Sacramento, California, United States
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Lens-based wavefront sensorless adaptive optics swept source OCT. Sci Rep 2016; 6:27620. [PMID: 27278853 PMCID: PMC4899788 DOI: 10.1038/srep27620] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 05/23/2016] [Indexed: 11/08/2022] Open
Abstract
Optical coherence tomography (OCT) has revolutionized modern ophthalmology, providing depth resolved images of the retinal layers in a system that is suited to a clinical environment. Although the axial resolution of OCT system, which is a function of the light source bandwidth, is sufficient to resolve retinal features at a micrometer scale, the lateral resolution is dependent on the delivery optics and is limited by ocular aberrations. Through the combination of wavefront sensorless adaptive optics and the use of dual deformable transmissive optical elements, we present a compact lens-based OCT system at an imaging wavelength of 1060 nm for high resolution retinal imaging. We utilized a commercially available variable focal length lens to correct for a wide range of defocus commonly found in patient’s eyes, and a novel multi-actuator adaptive lens for aberration correction to achieve near diffraction limited imaging performance at the retina. With a parallel processing computational platform, high resolution cross-sectional and en face retinal image acquisition and display was performed in real time. In order to demonstrate the system functionality and clinical utility, we present images of the photoreceptor cone mosaic and other retinal layers acquired in vivo from research subjects.
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49
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Cua M, Lee S, Miao D, Ju MJ, Mackenzie PJ, Jian Y, Sarunic MV. Retinal optical coherence tomography at 1 μm with dynamic focus control and axial motion tracking. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:26007. [PMID: 26882449 DOI: 10.1117/1.jbo.21.2.026007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 01/19/2016] [Indexed: 05/05/2023]
Abstract
High-resolution optical coherence tomography (OCT) retinal imaging is important to noninvasively visualize the various retinal structures to aid in better understanding of the pathogenesis of vision-robbing diseases. However, conventional OCT systems have a trade-off between lateral resolution and depth-of-focus. In this report, we present the development of a focus-stacking OCT system with automatic focus optimization for high-resolution, extended-focal-range clinical retinal imaging by incorporating a variable-focus liquid lens into the sample arm optics. Retinal layer tracking and selection was performed using a graphics processing unit accelerated processing platform for focus optimization, providing real-time layer-specific en face visualization. After optimization, multiple volumes focused at different depths were acquired, registered, and stitched together to yield a single, high-resolution focus-stacked dataset. Using this system, we show high-resolution images of the retina and optic nerve head, from which we extracted clinically relevant parameters such as the nerve fiber layer thickness and lamina cribrosa microarchitecture.
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Affiliation(s)
- Michelle Cua
- Simon Fraser University, Department of Engineering Science, 8888 University Drive, Burnaby, British Columbia V5A1S6, Canada
| | - Sujin Lee
- Simon Fraser University, Department of Engineering Science, 8888 University Drive, Burnaby, British Columbia V5A1S6, Canada
| | - Dongkai Miao
- Simon Fraser University, Department of Engineering Science, 8888 University Drive, Burnaby, British Columbia V5A1S6, Canada
| | - Myeong Jin Ju
- Simon Fraser University, Department of Engineering Science, 8888 University Drive, Burnaby, British Columbia V5A1S6, Canada
| | - Paul J Mackenzie
- University of British Columbia, Department of Ophthalmology and Visual Science, Eye Care Center, 2550 Willow Street, Vancouver, British Columbia V5Z 3N9, Canada
| | - Yifan Jian
- Simon Fraser University, Department of Engineering Science, 8888 University Drive, Burnaby, British Columbia V5A1S6, Canada
| | - Marinko V Sarunic
- Simon Fraser University, Department of Engineering Science, 8888 University Drive, Burnaby, British Columbia V5A1S6, Canada
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50
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Wahl DJ, Jian Y, Bonora S, Zawadzki RJ, Sarunic MV. Wavefront sensorless adaptive optics fluorescence biomicroscope for in vivo retinal imaging in mice. BIOMEDICAL OPTICS EXPRESS 2016; 7:1-12. [PMID: 26819812 PMCID: PMC4722895 DOI: 10.1364/boe.7.000001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 10/15/2015] [Accepted: 10/21/2015] [Indexed: 05/18/2023]
Abstract
Cellular-resolution in vivo fluorescence imaging is a valuable tool for longitudinal studies of retinal function in vision research. Wavefront sensorless adaptive optics (WSAO) is a developing technology that enables high-resolution imaging of the mouse retina. In place of the conventional method of using a Shack-Hartmann wavefront sensor to measure the aberrations directly, WSAO uses an image quality metric and a search algorithm to drive the shape of the adaptive element (i.e. deformable mirror). WSAO is a robust approach to AO and it is compatible with a compact, low-cost lens-based system. In this report, we demonstrated a hill-climbing algorithm for WSAO with a variable focus lens and deformable mirror for non-invasive in vivo imaging of EGFP (enhanced green fluorescent protein) labelled ganglion cells and microglia cells in the mouse retina.
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Affiliation(s)
- Daniel J. Wahl
- Engineering Science, Simon Fraser University, Burnaby BC, V5A 1S6 Canada
- These authors contributed equally to this work
| | - Yifan Jian
- Engineering Science, Simon Fraser University, Burnaby BC, V5A 1S6 Canada
- These authors contributed equally to this work
| | - Stefano Bonora
- CNR-Institute for Photonics and Nanotechnology, Via Trasea 7, 35131, Padova, Italy
- Hilase project, Institute of Physics AS CR v.v.i., Na Slovance 2, 18221, Prague, Czech Republic
| | - Robert J. Zawadzki
- UC Davis RISE Small Animal Ocular Imaging Facility, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA 95616 USA
- Vision Science and Advanced Retinal Imaging Laboratory (VSRI), Department of Ophthalmology & Vision Science, University of California Davis, Sacramento, CA 95817 USA
| | - Marinko V. Sarunic
- Engineering Science, Simon Fraser University, Burnaby BC, V5A 1S6 Canada
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