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Rui Y, Zhang M, Lee DM, Snyder VC, Raghuraman R, Gofas-Salas E, Mecê P, Yadav S, Tiruveedhula P, Grieve K, Sahel JA, Errera MH, Rossi EA. Label-Free Imaging of Inflammation at the Level of Single Cells in the Living Human Eye. OPHTHALMOLOGY SCIENCE 2024; 4:100475. [PMID: 38881602 PMCID: PMC11179426 DOI: 10.1016/j.xops.2024.100475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 12/22/2023] [Accepted: 01/16/2024] [Indexed: 06/18/2024]
Abstract
Purpose Putative microglia were recently detected using adaptive optics ophthalmoscopy in healthy eyes. Here we evaluate the use of nonconfocal adaptive optics scanning light ophthalmoscopy (AOSLO) for quantifying the morphology and motility of presumed microglia and other immune cells in eyes with retinal inflammation from uveitis and healthy eyes. Design Observational exploratory study. Participants Twelve participants were imaged, including 8 healthy participants and 4 posterior uveitis patients recruited from the clinic of 1 of the authors (M.H.E.). Methods The Pittsburgh AOSLO imaging system was used with a custom-designed 7-fiber optical fiber bundle for simultaneous confocal and nonconfocal multioffset detection. The inner retina was imaged at several locations at multiple timepoints in healthy participants and uveitis patients to generate time-lapse images. Main Outcome Measures Microglia and macrophages were manually segmented from nonconfocal AOSLO images, and their morphological characteristics quantified (including soma size, diameter, and circularity). Cell soma motion was quantified across time for periods of up to 30 minutes and their speeds were calculated by measuring their displacement over time. Results A spectrum of cell morphologies was detected in healthy eyes from circular amoeboid cells to elongated cells with visible processes, resembling activated and ramified microglia, respectively. Average soma diameter was 16.1 ± 0.9 μm. Cell movement was slow in healthy eyes (0.02 μm/sec on average), but macrophage-like cells moved rapidly in some uveitis patients (up to 3 μm/sec). In an eye with infectious uveitis, many macrophage-like cells were detected; during treatment their quantity and motility decreased as vision improved. Conclusions In vivo adaptive optics ophthalmoscopy offers promise as a potentially powerful tool for detecting and monitoring inflammation and response to treatment at a cellular level in the living eye. Financial Disclosures Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Affiliation(s)
- Yuhua Rui
- Department of Ophthalmology, University of Pittsburgh School of Medicine Pittsburgh, Pennsylvania
- Eye Center of Xiangya Hospital, Central South University Hunan Key Laboratory of Ophthalmology Changsha, Hunan, China
| | - Min Zhang
- Department of Ophthalmology, University of Pittsburgh School of Medicine Pittsburgh, Pennsylvania
| | - Daniel M.W. Lee
- Department of Bioengineering, University of Pittsburgh Swanson School of Engineering Pittsburgh, Pennsylvania
| | - Valerie C. Snyder
- Department of Ophthalmology, University of Pittsburgh School of Medicine Pittsburgh, Pennsylvania
| | - Rashmi Raghuraman
- Department of Ophthalmology, University of Pittsburgh School of Medicine Pittsburgh, Pennsylvania
| | - Elena Gofas-Salas
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, Paris, France
| | - Pedro Mecê
- Institut Langevin, ESPCI Paris, Université PSL, CNRS, Paris, France
| | - Sanya Yadav
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | | | - Kate Grieve
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, Paris, France
| | - José-Alain Sahel
- Department of Ophthalmology, University of Pittsburgh School of Medicine Pittsburgh, Pennsylvania
| | - Marie-Hélène Errera
- Department of Ophthalmology, University of Pittsburgh School of Medicine Pittsburgh, Pennsylvania
| | - Ethan A. Rossi
- Department of Ophthalmology, University of Pittsburgh School of Medicine Pittsburgh, Pennsylvania
- Department of Bioengineering, University of Pittsburgh Swanson School of Engineering Pittsburgh, Pennsylvania
- McGowan Institute for Regenerative Medicine Pittsburgh, Pennsylvania
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Govindahari V, Dornier R, Ferdowsi S, Moser C, Mantel I, Behar-Cohen F, Kowalczuk L. High-resolution adaptive optics-trans-scleral flood illumination (AO-TFI) imaging of retinal pigment epithelium (RPE) in central serous chorioretinopathy (CSCR). Sci Rep 2024; 14:13689. [PMID: 38871803 DOI: 10.1038/s41598-024-64524-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 06/10/2024] [Indexed: 06/15/2024] Open
Abstract
This study aims to correlate adaptive optics-transscleral flood illumination (AO-TFI) images of the retinal pigment epithelium (RPE) in central serous chorioretinopathy (CSCR) with standard clinical images and compare cell morphological features with those of healthy eyes. After stitching 125 AO-TFI images acquired in CSCR eyes (including 6 active CSCR, 15 resolved CSCR, and 3 from healthy contralateral), 24 montages were correlated with blue-autofluorescence, infrared and optical coherence tomography images. All 68 AO-TFI images acquired in pathological areas exhibited significant RPE contrast changes. Among the 52 healthy areas in clinical images, AO-TFI revealed a normal RPE mosaic in 62% of the images and an altered RPE pattern in 38% of the images. Morphological features of the RPE cells were quantified in 54 AO-TFI images depicting clinically normal areas (from 12 CSCR eyes). Comparison with data from 149 AO-TFI images acquired in 33 healthy eyes revealed significantly increased morphological heterogeneity. In CSCR, AO-TFI not only enabled high-resolution imaging of outer retinal alterations, but also revealed RPE abnormalities undetectable by all other imaging modalities. Further studies are required to estimate the prognosis value of these abnormalities. Imaging of the RPE using AO-TFI holds great promise for improving our understanding of the CSCR pathogenesis.
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Affiliation(s)
- Vishal Govindahari
- Department of Retina, Pushpagiri Eye Institute, Hyderabad, 500026, India
- INSERM UMRS 1138 From Physiopathology of Ocular Diseases to Clinical Developments, Centre de Recherche des Cordeliers, Université Pierre et Marie Curie - Paris 6, 75006, Paris, France
| | - Rémy Dornier
- Laboratory of Applied Photonic Devices (LAPD), School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | | | - Christophe Moser
- Laboratory of Applied Photonic Devices (LAPD), School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Irmela Mantel
- Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, CH-1004, Lausanne, Switzerland
- Faculty of Biology and Medicine, University of Lausanne, CH-1005, Lausanne, Switzerland
| | - Francine Behar-Cohen
- INSERM UMRS 1138 From Physiopathology of Ocular Diseases to Clinical Developments, Centre de Recherche des Cordeliers, Université Pierre et Marie Curie - Paris 6, 75006, Paris, France
- Assistance Publique - Hôpitaux de Paris, Ophtalmopôle, Cochin Hospital, 75014, Paris, France
- Université Paris Cité, 75006, Paris, France
- Hôpital Foch, Suresnes, France
| | - Laura Kowalczuk
- Laboratory of Applied Photonic Devices (LAPD), School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.
- Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, CH-1004, Lausanne, Switzerland.
- Faculty of Biology and Medicine, University of Lausanne, CH-1005, Lausanne, Switzerland.
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Das V, Zhang F, Bower AJ, Li J, Liu T, Aguilera N, Alvisio B, Liu Z, Hammer DX, Tam J. Revealing speckle obscured living human retinal cells with artificial intelligence assisted adaptive optics optical coherence tomography. COMMUNICATIONS MEDICINE 2024; 4:68. [PMID: 38600290 PMCID: PMC11006674 DOI: 10.1038/s43856-024-00483-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 03/13/2024] [Indexed: 04/12/2024] Open
Abstract
BACKGROUND In vivo imaging of the human retina using adaptive optics optical coherence tomography (AO-OCT) has transformed medical imaging by enabling visualization of 3D retinal structures at cellular-scale resolution, including the retinal pigment epithelial (RPE) cells, which are essential for maintaining visual function. However, because noise inherent to the imaging process (e.g., speckle) makes it difficult to visualize RPE cells from a single volume acquisition, a large number of 3D volumes are typically averaged to improve contrast, substantially increasing the acquisition duration and reducing the overall imaging throughput. METHODS Here, we introduce parallel discriminator generative adversarial network (P-GAN), an artificial intelligence (AI) method designed to recover speckle-obscured cellular features from a single AO-OCT volume, circumventing the need for acquiring a large number of volumes for averaging. The combination of two parallel discriminators in P-GAN provides additional feedback to the generator to more faithfully recover both local and global cellular structures. Imaging data from 8 eyes of 7 participants were used in this study. RESULTS We show that P-GAN not only improves RPE cell contrast by 3.5-fold, but also improves the end-to-end time required to visualize RPE cells by 99-fold, thereby enabling large-scale imaging of cells in the living human eye. RPE cell spacing measured across a large set of AI recovered images from 3 participants were in agreement with expected normative ranges. CONCLUSIONS The results demonstrate the potential of AI assisted imaging in overcoming a key limitation of RPE imaging and making it more accessible in a routine clinical setting.
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Affiliation(s)
- Vineeta Das
- National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Furu Zhang
- National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Andrew J Bower
- National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Joanne Li
- National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Tao Liu
- National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Nancy Aguilera
- National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Bruno Alvisio
- National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Zhuolin Liu
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Daniel X Hammer
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Johnny Tam
- National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
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Gofas-Salas E, Lee DMW, Rondeau C, Grieve K, Rossi EA, Paques M, Gocho K. Comparison between Two Adaptive Optics Methods for Imaging of Individual Retinal Pigmented Epithelial Cells. Diagnostics (Basel) 2024; 14:768. [PMID: 38611681 PMCID: PMC11012195 DOI: 10.3390/diagnostics14070768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 03/18/2024] [Accepted: 03/27/2024] [Indexed: 04/14/2024] Open
Abstract
The Retinal Pigment Epithelium (RPE) plays a prominent role in diseases such as age-related macular degeneration, but imaging individual RPE cells is challenging due to their high absorption and low autofluorescence emission. The RPE lies beneath the highly reflective photoreceptor layer (PR) and contains absorptive pigments, preventing direct backscattered light detection when the PR layer is intact. Here, we used near-infrared autofluorescence adaptive optics scanning laser ophthalmoscopy (NIRAF AOSLO) and transscleral flood imaging (TFI) in the same healthy eyes to cross-validate these approaches. Both methods revealed a consistent RPE mosaic pattern and appeared to reflect a distribution of fluorophores consistent with findings from histological studies. Interestingly, even in apparently healthy RPE, we observed dynamic changes over months, suggesting ongoing cellular activity or alterations in fluorophore distribution. These findings emphasize the value of NIRAF AOSLO and TFI in understanding RPE morphology and dynamics.
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Affiliation(s)
- Elena Gofas-Salas
- Department of Photonics, Institut de la Vision, INSERM, CNRS, Sorbonne Université, 17 rue Moreau, F-75012 Paris, France;
- CIC 1423, CHNO des Quinze-Vingts, INSERM-DGOS 28 rue de Charenton, F-75012 Paris, France; (M.P.); (K.G.)
| | - Daniel M. W. Lee
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, USA; (D.M.W.L.); (E.A.R.)
| | | | - Kate Grieve
- Department of Photonics, Institut de la Vision, INSERM, CNRS, Sorbonne Université, 17 rue Moreau, F-75012 Paris, France;
- CIC 1423, CHNO des Quinze-Vingts, INSERM-DGOS 28 rue de Charenton, F-75012 Paris, France; (M.P.); (K.G.)
| | - Ethan A. Rossi
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, USA; (D.M.W.L.); (E.A.R.)
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA
| | - Michel Paques
- CIC 1423, CHNO des Quinze-Vingts, INSERM-DGOS 28 rue de Charenton, F-75012 Paris, France; (M.P.); (K.G.)
| | - Kiyoko Gocho
- CIC 1423, CHNO des Quinze-Vingts, INSERM-DGOS 28 rue de Charenton, F-75012 Paris, France; (M.P.); (K.G.)
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5
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Anderson DM, Brager DC, Kearsley AJ. Spatially-dependent model for rods and cones in the retina. J Theor Biol 2024; 579:111687. [PMID: 38103677 DOI: 10.1016/j.jtbi.2023.111687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 10/17/2023] [Accepted: 11/27/2023] [Indexed: 12/19/2023]
Abstract
We develop a mathematical model for photoreceptors in the retina. We focus on rod and cone outer segment dynamics and interactions with a nutrient source associated with the retinal pigment epithelium cells. Rod and cone densities (number per unit area of retinal surface) are known to have significant spatial dependence in the retina with cones located primarily near the fovea and the rods located primarily away from the fovea. Our model accounts for this spatial dependence of the rod and cone photoreceptor density as well as for the possibility of nutrient diffusion. We present equilibrium and dynamic solutions, discuss their relation to existing models, and estimate model parameters through comparisons with available experimental measurements of both spatial and temporal photoreceptor characteristics. Our model compares well with existing data on spatially-dependent regrowth of photoreceptor outer segments in the macular region of Rhesus Monkeys. Our predictions are also consistent with existing data on the spatial dependence of photoreceptor outer segment length near the fovea in healthy human subjects. We focus primarily on the healthy eye but our model could be the basis for future efforts designed to explore various retinal pathologies, eye-related injuries, and treatments of these conditions.
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Affiliation(s)
- Daniel M Anderson
- Applied & Computational Mathematics Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, 20899, MD, USA; Department of Mathematical Sciences, George Mason University, 4400 University Drive, Fairfax, 22030, VA, USA.
| | - Danielle C Brager
- Applied & Computational Mathematics Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, 20899, MD, USA.
| | - Anthony J Kearsley
- Applied & Computational Mathematics Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, 20899, MD, USA.
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6
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Luo T, Gilbert RN, Sapoznik KA, Walker BR, Burns SA. Automatic montaging of adaptive optics SLO retinal images based on graph theory. BIOMEDICAL OPTICS EXPRESS 2024; 15:1021-1037. [PMID: 38404321 PMCID: PMC10890876 DOI: 10.1364/boe.505013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 01/15/2024] [Accepted: 01/15/2024] [Indexed: 02/27/2024]
Abstract
We present a fully automatic montage pipeline for adaptive optics SLO retinal images. It contains a flexible module to estimate the translation between pairwise images. The user can change modules to accommodate the alignment of the dataset using the most appropriate alignment technique, provided that it estimates the translation between image pairs and provides a quantitative confidence metric for the match between 0 and 1. We use these pairwise comparisons and associated metrics to construct a graph where nodes represent frames and edges represent the overlap relations. We use a small diameter spanning tree to determine the best pairwise alignment for each image based on the entire set of image relations. The final stage of the pipeline is a blending module that uses dynamic programming to improve the smoothness of the transition between frames. Data sets ranging from 26 to 119 images were obtained from individuals aged 24 to 81 years with a mix of visually normal control eyes and eyes with glaucoma or diabetes. The resulting automatically generated montages were qualitatively and quantitatively compared to results from semi-automated alignment. Data sets were specifically chosen to include both high quality and medium quality data. The results obtained from the automatic method are comparable or better than results obtained by an experienced operator performing semi-automated montaging. For the plug-in pairwise alignment module, we tested a technique that utilizes SIFT + RANSAC, Normalized cross-correlation (NCC) and a combination of the two. This pipeline produces consistent results not only on outer retinal layers, but also on inner retinal layers such as a nerve fiber layer or images of the vascular complexes, even when images are not of excellent quality.
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Affiliation(s)
- Ting Luo
- School of Optometry, Indiana University, 800 E. Atwater Ave, Bloomington, IN 47405, USA
| | - Robert N. Gilbert
- School of Optometry, Indiana University, 800 E. Atwater Ave, Bloomington, IN 47405, USA
| | - Kaitlyn A. Sapoznik
- School of Optometry, Indiana University, 800 E. Atwater Ave, Bloomington, IN 47405, USA
- College of Optometry, University of Houston, 4401 Martin Luther King Blvd, Houston, TX 77204, USA
| | - Brittany R. Walker
- School of Optometry, Indiana University, 800 E. Atwater Ave, Bloomington, IN 47405, USA
| | - Stephen A. Burns
- School of Optometry, Indiana University, 800 E. Atwater Ave, Bloomington, IN 47405, USA
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7
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von der Emde L, Saßmannshausen M, Morelle O, Rennen G, Holz FG, Wintergerst MWM, Ach T. Reliability of Retinal Layer Annotation with a Novel, High-Resolution Optical Coherence Tomography Device: A Comparative Study. Bioengineering (Basel) 2023; 10:bioengineering10040438. [PMID: 37106625 PMCID: PMC10136209 DOI: 10.3390/bioengineering10040438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 03/24/2023] [Accepted: 03/25/2023] [Indexed: 04/03/2023] Open
Abstract
Optical coherence tomography (OCT) enables in vivo diagnostics of individual retinal layers in the living human eye. However, improved imaging resolution could aid diagnosis and monitoring of retinal diseases and identify potential new imaging biomarkers. The investigational high-resolution OCT platform (High-Res OCT; 853 nm central wavelength, 3 µm axial-resolution) has an improved axial resolution by shifting the central wavelength and increasing the light source bandwidth compared to a conventional OCT device (880 nm central wavelength, 7 µm axial-resolution). To assess the possible benefit of a higher resolution, we compared the retest reliability of retinal layer annotation from conventional and High-Res OCT, evaluated the use of High-Res OCT in patients with age-related macular degeneration (AMD), and assessed differences of both devices on subjective image quality. Thirty eyes of 30 patients with early/intermediate AMD (iAMD; mean age 75 ± 8 years) and 30 eyes of 30 age-similar subjects without macular changes (62 ± 17 years) underwent identical OCT imaging on both devices. Inter- and intra-reader reliability were analyzed for manual retinal layer annotation using EyeLab. Central OCT B-scans were graded for image quality by two graders and a mean-opinion-score (MOS) was formed and evaluated. Inter- and intra-reader reliability were higher for High-Res OCT (greatest benefit for inter-reader reliability: ganglion cell layer; for intra-reader reliability: retinal nerve fiber layer). High-Res OCT was significantly associated with an improved MOS (MOS 9/8, Z-value = 5.4, p < 0.01) mainly due to improved subjective resolution (9/7, Z-Value 6.2, p < 0.01). The retinal pigment epithelium drusen complex showed a trend towards improved retest reliability in High-Res OCT in iAMD eyes but without statistical significance. Improved axial resolution of the High-Res OCT benefits retest reliability of retinal layer annotation and improves perceived image quality and resolution. Automated image analysis algorithms could also benefit from the increased image resolution.
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Affiliation(s)
- Leon von der Emde
- Department of Ophthalmology, University Hospital Bonn, 53127 Bonn, Germany
| | | | - Olivier Morelle
- B-IT and Institut for Informatics, Universität Bonn, 53127 Bonn, Germany
| | - Geena Rennen
- Department of Ophthalmology, University Hospital Bonn, 53127 Bonn, Germany
| | - Frank G. Holz
- Department of Ophthalmology, University Hospital Bonn, 53127 Bonn, Germany
| | | | - Thomas Ach
- Department of Ophthalmology, University Hospital Bonn, 53127 Bonn, Germany
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8
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Lee B, Jeong S, Lee J, Kim TS, Braaf B, Vakoc BJ, Oh WY. Wide-Field Three-Dimensional Depth-Invariant Cellular-Resolution Imaging of the Human Retina. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2203357. [PMID: 36642824 PMCID: PMC10023497 DOI: 10.1002/smll.202203357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 12/02/2022] [Indexed: 06/17/2023]
Abstract
Three-dimensional (3D) cellular-resolution imaging of the living human retina over a large field of view will bring a great impact in clinical ophthalmology, potentially finding new biomarkers for early diagnosis and improving the pathophysiological understanding of ocular diseases. While hardware-based and computational adaptive optics (AO) optical coherence tomography (OCT) have been developed to achieve cellular-resolution retinal imaging, these approaches support limited 3D imaging fields, and their high cost and intrinsic hardware complexity limit their practical utility. Here, this work demonstrates 3D depth-invariant cellular-resolution imaging of the living human retina over a 3 × 3 mm field of view using the first intrinsically phase-stable multi-MHz retinal swept-source OCT and novel computational defocus and aberration correction methods. Single-acquisition imaging of photoreceptor cells, retinal nerve fiber layer, and retinal capillaries is presented across unprecedented imaging fields. By providing wide-field 3D cellular-resolution imaging in the human retina using a standard point-scan architecture routinely used in the clinic, this platform proposes a strategy for expanded utilization of high-resolution retinal imaging in both research and clinical settings.
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Affiliation(s)
- ByungKun Lee
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
- KI for Health Science and Technology, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Sunhong Jeong
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
- KI for Health Science and Technology, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Joosung Lee
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
- KI for Health Science and Technology, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Tae Shik Kim
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston 02140, USA
| | - Boy Braaf
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston 02140, USA
| | - Benjamin J. Vakoc
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston 02140, USA
| | - Wang-Yuhl Oh
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
- KI for Health Science and Technology, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
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9
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Soltanian-Zadeh S, Liu Z, Liu Y, Lassoued A, Cukras CA, Miller DT, Hammer DX, Farsiu S. Deep learning-enabled volumetric cone photoreceptor segmentation in adaptive optics optical coherence tomography images of normal and diseased eyes. BIOMEDICAL OPTICS EXPRESS 2023; 14:815-833. [PMID: 36874491 PMCID: PMC9979662 DOI: 10.1364/boe.478693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 06/11/2023]
Abstract
Objective quantification of photoreceptor cell morphology, such as cell diameter and outer segment length, is crucial for early, accurate, and sensitive diagnosis and prognosis of retinal neurodegenerative diseases. Adaptive optics optical coherence tomography (AO-OCT) provides three-dimensional (3-D) visualization of photoreceptor cells in the living human eye. The current gold standard for extracting cell morphology from AO-OCT images involves the tedious process of 2-D manual marking. To automate this process and extend to 3-D analysis of the volumetric data, we propose a comprehensive deep learning framework to segment individual cone cells in AO-OCT scans. Our automated method achieved human-level performance in assessing cone photoreceptors of healthy and diseased participants captured with three different AO-OCT systems representing two different types of point scanning OCT: spectral domain and swept source.
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Affiliation(s)
| | - Zhuolin Liu
- Center for Devices and Radiological Health (CDRH), U.S. Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Yan Liu
- School of Optometry, Indiana University, Bloomington, IN 47405, USA
| | - Ayoub Lassoued
- School of Optometry, Indiana University, Bloomington, IN 47405, USA
| | - Catherine A. Cukras
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Donald T. Miller
- School of Optometry, Indiana University, Bloomington, IN 47405, USA
| | - Daniel X. Hammer
- Center for Devices and Radiological Health (CDRH), U.S. Food and Drug Administration, Silver Spring, MD 20993, 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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10
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Morgan JIW, Chui TYP, Grieve K. Twenty-five years of clinical applications using adaptive optics ophthalmoscopy [Invited]. BIOMEDICAL OPTICS EXPRESS 2023; 14:387-428. [PMID: 36698659 PMCID: PMC9841996 DOI: 10.1364/boe.472274] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 11/22/2022] [Accepted: 11/27/2022] [Indexed: 05/02/2023]
Abstract
Twenty-five years ago, adaptive optics (AO) was combined with fundus photography, thereby initiating a new era in the field of ophthalmic imaging. Since that time, clinical applications of AO ophthalmoscopy to investigate visual system structure and function in both health and disease abound. To date, AO ophthalmoscopy has enabled visualization of most cell types in the retina, offered insight into retinal and systemic disease pathogenesis, and been integrated into clinical trials. This article reviews clinical applications of AO ophthalmoscopy and addresses remaining challenges for AO ophthalmoscopy to become fully integrated into standard ophthalmic care.
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Affiliation(s)
- Jessica I. W. Morgan
- Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Contributed equally
| | - Toco Y. P. Chui
- Department of Ophthalmology, The New York Eye and Ear Infirmary of Mount Sinai, New York, NY 10003, USA
- Contributed equally
| | - Kate Grieve
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, and CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, 28 rue de Charenton, F-75012 Paris, France
- Contributed equally
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11
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Liu Z, Zhang F, Zucca K, Agrawal A, Hammer DX. Ultrahigh-speed multimodal adaptive optics system for microscopic structural and functional imaging of the human retina. BIOMEDICAL OPTICS EXPRESS 2022; 13:5860-5878. [PMID: 36733751 PMCID: PMC9872887 DOI: 10.1364/boe.462594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 09/16/2022] [Accepted: 09/20/2022] [Indexed: 05/02/2023]
Abstract
We describe the design and performance of a multimodal and multifunctional adaptive optics (AO) system that combines scanning laser ophthalmoscopy (SLO) and optical coherence tomography (OCT) for simultaneous retinal imaging at 13.4 Hz. The high-speed AO-OCT channel uses a 3.4 MHz Fourier-domain mode-locked (FDML) swept source. The system achieves exquisite resolution and sensitivity for pan-macular and transretinal visualization of retinal cells and structures while providing a functional assessment of the cone photoreceptors. The ultra-high speed also enables wide-field scans for clinical usability and angiography for vascular visualization. The FDA FDML-AO system is a powerful platform for studying various retinal and neurological diseases for vision science research, retina physiology investigation, and biomarker development.
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Affiliation(s)
- Zhuolin Liu
- Center for Devices and Radiological Health
(CDRH), U. S. Food and Drug Administration (FDA), Silver Spring, Maryland 20993, USA
| | - Furu Zhang
- Center for Devices and Radiological Health
(CDRH), U. S. Food and Drug Administration (FDA), Silver Spring, Maryland 20993, USA
- Co-first author
| | - Kelvy Zucca
- Center for Devices and Radiological Health
(CDRH), U. S. Food and Drug Administration (FDA), Silver Spring, Maryland 20993, USA
| | - Anant Agrawal
- Center for Devices and Radiological Health
(CDRH), U. S. Food and Drug Administration (FDA), Silver Spring, Maryland 20993, USA
| | - Daniel X. Hammer
- Center for Devices and Radiological Health
(CDRH), U. S. Food and Drug Administration (FDA), Silver Spring, Maryland 20993, USA
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12
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Tan LX, Li J, Germer CJ, Lakkaraju A. Analysis of mitochondrial dynamics and function in the retinal pigment epithelium by high-speed high-resolution live imaging. Front Cell Dev Biol 2022; 10:1044672. [PMID: 36393836 PMCID: PMC9651161 DOI: 10.3389/fcell.2022.1044672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 10/19/2022] [Indexed: 11/13/2022] Open
Abstract
Mitochondrial dysfunction is strongly implicated in neurodegenerative diseases including age-related macular degeneration (AMD), which causes irreversible blindness in over 50 million older adults worldwide. A key site of insult in AMD is the retinal pigment epithelium (RPE), a monolayer of postmitotic polarized cells that performs essential functions for photoreceptor health and vision. Recent studies from our group and others have identified several features of mitochondrial dysfunction in AMD including mitochondrial fragmentation and bioenergetic defects. While these studies provide valuable insight at fixed points in time, high-resolution, high-speed live imaging is essential for following mitochondrial injury in real time and identifying disease mechanisms. Here, we demonstrate the advantages of live imaging to investigate RPE mitochondrial dynamics in cell-based and mouse models. We show that mitochondria in the RPE form extensive networks that are destroyed by fixation and discuss important live imaging considerations that can interfere with accurate evaluation of mitochondrial integrity such as RPE differentiation status and acquisition parameters. Our data demonstrate that RPE mitochondria show localized heterogeneities in membrane potential and ATP production that could reflect focal changes in metabolism and oxidative stress. Contacts between the mitochondria and organelles such as the ER and lysosomes mediate calcium flux and mitochondrial fission. Live imaging of mouse RPE flatmounts revealed a striking loss of mitochondrial integrity in albino mouse RPE compared to pigmented mice that could have significant functional consequences for cellular metabolism. Our studies lay a framework to guide experimental design and selection of model systems for evaluating mitochondrial health and function in the RPE.
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Affiliation(s)
- Li Xuan Tan
- Department of Ophthalmology, School of Medicine, University of California, San Francisco, CA, United States
| | - Jianlong Li
- Department of Cell and Tissue Biology, School of Dentistry, University of California, San Francisco, CA, United States
| | - Colin J. Germer
- Department of Ophthalmology, School of Medicine, University of California, San Francisco, CA, United States
- Pharmaceutical Sciences and Pharmacogenomics Graduate Program, University of California, San Francisco, CA, United States
| | - Aparna Lakkaraju
- Department of Ophthalmology, School of Medicine, University of California, San Francisco, CA, United States
- Pharmaceutical Sciences and Pharmacogenomics Graduate Program, University of California, San Francisco, CA, United States
- Department of Anatomy, School of Medicine, University of California, San Francisco, CA, United States
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13
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Kowalczuk L, Dornier R, Kunzi M, Iskandar A, Misutkova Z, Gryczka A, Navarro A, Jeunet F, Mantel I, Behar-Cohen F, Laforest T, Moser C. In Vivo Retinal Pigment Epithelium Imaging using Transscleral Optical Imaging in Healthy Eyes. OPHTHALMOLOGY SCIENCE 2022; 3:100234. [PMID: 36545259 PMCID: PMC9762198 DOI: 10.1016/j.xops.2022.100234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 10/10/2022] [Accepted: 10/12/2022] [Indexed: 11/05/2022]
Abstract
Objective To image healthy retinal pigment epithelial (RPE) cells in vivo using Transscleral OPtical Imaging (TOPI) and to analyze statistics of RPE cell features as a function of age, axial length (AL), and eccentricity. Design Single-center, exploratory, prospective, and descriptive clinical study. Participants Forty-nine eyes (AL: 24.03 ± 0.93 mm; range: 21.9-26.7 mm) from 29 participants aged 21 to 70 years (37.1 ± 13.3 years; 19 men, 10 women). Methods Retinal images, including fundus photography and spectral-domain OCT, AL, and refractive error measurements were collected at baseline. For each eye, 6 high-resolution RPE images were acquired using TOPI at different locations, one of them being imaged 5 times to evaluate the repeatability of the method. Follow-up ophthalmic examination was repeated 1 to 3 weeks after TOPI to assess safety. Retinal pigment epithelial images were analyzed with a custom automated software to extract cell parameters. Statistical analysis of the selected high-contrast images included calculation of coefficient of variation (CoV) for each feature at each repetition and Spearman and Mann-Whitney tests to investigate the relationship between cell features and eye and subject characteristics. Main Outcome Measures Retinal pigment epithelial cell features: density, area, center-to-center spacing, number of neighbors, circularity, elongation, solidity, and border distance CoV. Results Macular RPE cell features were extracted from TOPI images at an eccentricity of 1.6° to 16.3° from the fovea. For each feature, the mean CoV was < 4%. Spearman test showed correlation within RPE cell features. In the perifovea, the region in which images were selected for all participants, longer AL significantly correlated with decreased RPE cell density (R Spearman, Rs = -0.746; P < 0.0001) and increased cell area (Rs = 0.668; P < 0.0001), without morphologic changes. Aging was also significantly correlated with decreased RPE density (Rs = -0.391; P = 0.036) and increased cell area (Rs = 0.454; P = 0.013). Lower circular, less symmetric, more elongated, and larger cells were observed in those > 50 years. Conclusions The TOPI technology imaged RPE cells in vivo with a repeatability of < 4% for the CoV and was used to analyze the influence of physiologic factors on RPE cell morphometry in the perifovea of healthy volunteers. Financial Disclosures Proprietary or commercial disclosure may be found after the references.
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Key Words
- AF, autofluorescence
- AL, axial length
- AO, adaptive optics
- Adaptive Optics Transscleral Flood Illumination
- BCVA, best-corrected visual acuity
- CCS, center-to-center spacing
- CoV, coefficient of variation
- D, diopters
- FOV, field of view
- Healthy volunteers
- High resolution retinal imaging
- IOP, intraocular pressure
- NIR, near-infrared
- PRL, preferred retinal locus
- QC, quality criterion
- RE, refractive error
- RPE, retinal pigment epithelium
- Retinal Pigment Epithelium
- SD, standard deviation
- SLO, scanning laser ophthalmoscope
- TOPI, transscleral optical imaging
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Affiliation(s)
- Laura Kowalczuk
- Laboratory of Applied Photonic Devices, School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland,Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland,Jules-Gonin Eye Hospital, Fondation Asile des aveugles, Lausanne, Switzerland,Correspondence: Laura Kowalczuk, PhD, École Polytechnique Fédérale de Lausanne, School of Engineering, Institute of Electrical and Micro-engineering, Laboratory of Applied Photonics Devices, BM 4127, Station 17, CH-1015, Lausanne, Switzerland.
| | - Rémy Dornier
- Laboratory of Applied Photonic Devices, School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Mathieu Kunzi
- Laboratory of Applied Photonic Devices, School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Antonio Iskandar
- Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland,Jules-Gonin Eye Hospital, Fondation Asile des aveugles, Lausanne, Switzerland
| | - Zuzana Misutkova
- Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland,Jules-Gonin Eye Hospital, Fondation Asile des aveugles, Lausanne, Switzerland
| | - Aurélia Gryczka
- Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland,Jules-Gonin Eye Hospital, Fondation Asile des aveugles, Lausanne, Switzerland
| | - Aurélie Navarro
- Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland,Jules-Gonin Eye Hospital, Fondation Asile des aveugles, Lausanne, Switzerland
| | - Fanny Jeunet
- Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland,Jules-Gonin Eye Hospital, Fondation Asile des aveugles, Lausanne, Switzerland
| | - Irmela Mantel
- Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland,Jules-Gonin Eye Hospital, Fondation Asile des aveugles, Lausanne, Switzerland
| | - Francine Behar-Cohen
- Centre de Recherche des Cordeliers, Université Pierre et Marie Curie, Paris, France,INSERM U1138, USPC, Université de Paris-Cité, Sorbonne Université, Paris, France,Assistance Publique - Hôpitaux de Paris, Ophtalmopôle, Cochin Hospital, Paris, France,Université Paris Cité, Paris, France,Hôpital Foch, Suresnes, France
| | - Timothé Laforest
- Laboratory of Applied Photonic Devices, School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Christophe Moser
- Laboratory of Applied Photonic Devices, School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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14
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Srinivasan VJ, Kho AM, Chauhan P. Visible Light Optical Coherence Tomography Reveals the Relationship of the Myoid and Ellipsoid to Band 2 in Humans. Transl Vis Sci Technol 2022; 11:3. [PMID: 36053140 PMCID: PMC9440607 DOI: 10.1167/tvst.11.9.3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Purpose We employ visible light optical coherence tomography (OCT) to investigate the relationship between the myoid, ellipsoid, and band 2 in the living human retina. Rather than refute existing theories, we aim to reveal new bands and better delineate the structures at hand. Methods An upgraded spectral/Fourier domain visible light OCT prototype, with 1.0-µm axial resolution, imaged 13 eyes of 13 young adult human subjects (23–40 years old) without a history of ocular pathology. The external limiting membrane (band 1) and band 2 edges were segmented. Reflectivity was examined along the inner segment (IS), defined as extending from band 1 to the band 2 center, and within band 2 itself. Results Images highlight a nearly continuously resolved extrafoveal internal limiting membrane, the peripheral single-cell thick ganglion cell layer, and the peripheral photoreceptor axonal fiber layer, a peripheral division of band 2 into bands 2a and 2b, and a reflectivity-based division of the IS into “m” and “e” zones. Discussion Topography and transverse intensity variations of the outermost band 2b suggest an association with rods. The “m” and “e” zone border is consistent with the myoid–ellipsoid boundary, even recapitulating the well-documented distribution of mitochondria throughout the IS at the foveal center. Theories of outer retinal reflectivity in OCT must adequately explain these observations. Translational Relevance Findings support that band 2 does partially overlap with the ellipsoid in transversally averaged OCT images due to photoreceptor IS length dispersion but argue that the inner ellipsoid must be inner to band 2, as suggested by prior quantitative measurements.
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Affiliation(s)
- Vivek J Srinivasan
- Department of Ophthalmology, NYU Langone Health, New York, NY, USA.,Department of Radiology, NYU Langone Health, New York, NY, USA.,Tech4Health Institute, NYU Langone Health, New York, NY, USA.,Department of Biomedical Engineering, University of California, Davis, CA, USA
| | - Aaron M Kho
- Department of Biomedical Engineering, University of California, Davis, CA, USA
| | - Pooja Chauhan
- Department of Radiology, NYU Langone Health, New York, NY, USA.,Tech4Health Institute, NYU Langone Health, New York, NY, USA
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15
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von der Emde L, Vaisband M, Hasenauer J, Bourauel L, Bermond K, Saßmannshausen M, Heintzmann R, Holz FG, Curcio CA, Sloan KR, Ach T. Histologic Cell Shape Descriptors for the Retinal Pigment Epithelium in Age-Related Macular Degeneration: A Comparison to Unaffected Eyes. Transl Vis Sci Technol 2022; 11:19. [PMID: 35984669 PMCID: PMC9419462 DOI: 10.1167/tvst.11.8.19] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Phenotype alterations of the retinal pigment epithelium (RPE) are a main characteristic of age-related macular degeneration (AMD). Individual RPE cell shape descriptors may help to delineate healthy from AMD-affected cells in early disease stages. Methods Twenty-two human RPE flatmounts (7 eyes with AMD [early, 3; geographic atrophy, 1; neovascular, 3); 15 unaffected eyes [8 aged ≤51 years; 7 aged >80 years)] were imaged at the fovea, perifovea, and near periphery (predefined sample locations) using a laser-scanning confocal fluorescence microscope. RPE cell boundaries were manually marked with computer assistance. For each cell, 11 shape descriptors were calculated and correlated with donor age, cell autofluorescence (AF) intensity, and retinal location. Statistical analysis was performed using an ensemble classifier based on logistic regression. Results In AMD, RPE was altered at all locations (most pronounced at the fovea), with area, solidity, and form factor being the most discriminatory descriptors. In the unaffected macula, aging had no significant effect on cell shape factors; however, with increasing distance to the fovea, area, solidity, and convexity increased while form factor decreased. Reduced AF in AMD was significantly associated with decreased roundness and solidity. Conclusions AMD results in an altered RPE with enlarged and deformed cells that could precede clinically visible lesions and thus serve as early biomarkers for AMD onset. Our data may also help guide the interpretation of RPE morphology in in vivo studies utilizing high-resolution single-cell imaging. Translational Relevance Our histologic RPE cell shape data have the ability to identify robust biomarkers for the early detection of AMD-affected cells, which also could serve as a basis for automated segmentation of RPE sheets.
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Affiliation(s)
- Leon von der Emde
- Department of Ophthalmology, University Hospital Bonn, Bonn, Germany
| | - Marc Vaisband
- University of Bonn, Life & Medical Sciences Institute, Bonn, Germany.,Department of Internal Medicine III with Haematology, Medical Oncology, Haemostaseology, Infectiology and Rheumatology, Oncologic Center; Salzburg Cancer Research Institute-Laboratory for Immunological and Molecular Cancer Research (SCRI-LIMCR); Paracelsus Medical University, Salzburg, Austria, Cancer Cluster Salzburg, Austria
| | - Jan Hasenauer
- University of Bonn, Life & Medical Sciences Institute, Bonn, Germany.,Helmholtz Center Munich- German Research Center for Environmental Health, Institute of Computational Biology, Neuherberg, Germany
| | - Leonie Bourauel
- Department of Ophthalmology, University Hospital Bonn, Bonn, Germany
| | - Katharina Bermond
- Department of Ophthalmology, Ludwigshafen Hospital, Ludwigshafen, Germany
| | | | - Rainer Heintzmann
- Leibniz Institute of Photonic Technology, Jena, Germany.,Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University Jena, Jena, Germany
| | - Frank G Holz
- Department of Ophthalmology, University Hospital Bonn, Bonn, Germany
| | - Christine A Curcio
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, AL, USA
| | - Kenneth R Sloan
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, AL, USA
| | - Thomas Ach
- Department of Ophthalmology, University Hospital Bonn, Bonn, Germany
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16
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Alexopoulos P, Madu C, Wollstein G, Schuman JS. The Development and Clinical Application of Innovative Optical Ophthalmic Imaging Techniques. Front Med (Lausanne) 2022; 9:891369. [PMID: 35847772 PMCID: PMC9279625 DOI: 10.3389/fmed.2022.891369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/23/2022] [Indexed: 11/22/2022] Open
Abstract
The field of ophthalmic imaging has grown substantially over the last years. Massive improvements in image processing and computer hardware have allowed the emergence of multiple imaging techniques of the eye that can transform patient care. The purpose of this review is to describe the most recent advances in eye imaging and explain how new technologies and imaging methods can be utilized in a clinical setting. The introduction of optical coherence tomography (OCT) was a revolution in eye imaging and has since become the standard of care for a plethora of conditions. Its most recent iterations, OCT angiography, and visible light OCT, as well as imaging modalities, such as fluorescent lifetime imaging ophthalmoscopy, would allow a more thorough evaluation of patients and provide additional information on disease processes. Toward that goal, the application of adaptive optics (AO) and full-field scanning to a variety of eye imaging techniques has further allowed the histologic study of single cells in the retina and anterior segment. Toward the goal of remote eye care and more accessible eye imaging, methods such as handheld OCT devices and imaging through smartphones, have emerged. Finally, incorporating artificial intelligence (AI) in eye images has the potential to become a new milestone for eye imaging while also contributing in social aspects of eye care.
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Affiliation(s)
- Palaiologos Alexopoulos
- Department of Ophthalmology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY, United States
| | - Chisom Madu
- Department of Ophthalmology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY, United States
| | - Gadi Wollstein
- Department of Ophthalmology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY, United States
- Department of Biomedical Engineering, NYU Tandon School of Engineering, Brooklyn, NY, United States
- Center for Neural Science, College of Arts & Science, New York University, New York, NY, United States
| | - Joel S. Schuman
- Department of Ophthalmology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY, United States
- Department of Biomedical Engineering, NYU Tandon School of Engineering, Brooklyn, NY, United States
- Center for Neural Science, College of Arts & Science, New York University, New York, NY, United States
- Department of Electrical and Computer Engineering, NYU Tandon School of Engineering, Brooklyn, NY, United States
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17
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Multi-modal and multi-scale clinical retinal imaging system with pupil and retinal tracking. Sci Rep 2022; 12:9577. [PMID: 35688890 PMCID: PMC9187716 DOI: 10.1038/s41598-022-13631-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 05/17/2022] [Indexed: 11/08/2022] Open
Abstract
We present a compact multi-modal and multi-scale retinal imaging instrument with an angiographic functional extension for clinical use. The system integrates scanning laser ophthalmoscopy (SLO), optical coherence tomography (OCT) and OCT angiography (OCTA) imaging modalities and provides multi-scale fields of view. For high resolution, and high lateral resolution in particular, cellular imaging correction of aberrations by adaptive optics (AO) is employed. The entire instrument has a compact design and the scanning head is mounted on motorized translation stages that enable 3D self-alignment with respect to the subject's eye by tracking the pupil position. Retinal tracking, based on the information provided by SLO, is incorporated in the instrument to compensate for retinal motion during OCT imaging. The imaging capabilities of the multi-modal and multi-scale instrument were tested by imaging healthy volunteers and patients.
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18
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Abstract
The eye, the photoreceptive organ used to perceive the external environment, is of great importance to humans. It has been proven that some diseases in humans are accompanied by fundus changes; therefore, the health status of people may be interpreted from retinal images. However, the human eye is not a perfect refractive system for the existence of ocular aberrations. These aberrations not only affect the ability of human visual discrimination and recognition, but restrict the observation of the fine structures of human eye and reduce the possibility of exploring the mechanisms of eye disease. Adaptive optics (AO) is a technique that corrects optical wavefront aberrations. Once integrated into ophthalmoscopes, AO enables retinal imaging at the cellular level. This paper illustrates the principle of AO in correcting wavefront aberrations in human eyes, and then reviews the applications and advances of AO in ophthalmology, including the adaptive optics fundus camera (AO-FC), the adaptive optics scanning laser ophthalmoscope (AO-SLO), the adaptive optics optical coherence tomography (AO-OCT), and their combined multimodal imaging technologies. The future development trend of AO in ophthalmology is also prospected.
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19
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Fadjukov J, Wienbar S, Hakanen S, Aho V, Vihinen-Ranta M, Ihalainen TO, Schwartz GW, Nymark S. Gap junctions and connexin hemichannels both contribute to the electrical properties of retinal pigment epithelium. J Gen Physiol 2022; 154:213064. [PMID: 35275193 PMCID: PMC8922333 DOI: 10.1085/jgp.202112916] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 02/17/2022] [Indexed: 12/13/2022] Open
Abstract
Gap junctions are intercellular channels that permit the transfer of ions and small molecules between adjacent cells. These cellular junctions are particularly dense in the retinal pigment epithelium (RPE), and their contribution to many retinal diseases has been recognized. While gap junctions have been implicated in several aspects of RPE physiology, their role in shaping the electrical properties of these cells has not been characterized in mammals. The role of gap junctions in the electrical properties of the RPE is particularly important considering the growing appreciation of RPE as excitable cells containing various voltage-gated channels. We used a whole-cell patch clamp to measure the electrical characteristics and connectivity between RPE cells, both in cultures derived from human embryonic stem cells and in the intact RPE monolayers from mouse eyes. We found that the pharmacological blockade of gap junctions eliminated electrical coupling between RPE cells, and that the blockade of gap junctions or Cx43 hemichannels significantly increased their input resistance. These results demonstrate that gap junctions function in the RPE not only as a means of molecular transport but also as a regulator of electrical excitability.
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Affiliation(s)
- Julia Fadjukov
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Sophia Wienbar
- Department of Ophthalmology, Northwestern University, Chicago, IL.,Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL.,Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL
| | - Satu Hakanen
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
| | - Vesa Aho
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
| | - Maija Vihinen-Ranta
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
| | - Teemu O Ihalainen
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Gregory W Schwartz
- Department of Ophthalmology, Northwestern University, Chicago, IL.,Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL.,Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL
| | - Soile Nymark
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
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20
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Zouache MA. Variability in Retinal Neuron Populations and Associated Variations in Mass Transport Systems of the Retina in Health and Aging. Front Aging Neurosci 2022; 14:778404. [PMID: 35283756 PMCID: PMC8914054 DOI: 10.3389/fnagi.2022.778404] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 01/13/2022] [Indexed: 11/17/2022] Open
Abstract
Aging is associated with a broad range of visual impairments that can have dramatic consequences on the quality of life of those impacted. These changes are driven by a complex series of alterations affecting interactions between multiple cellular and extracellular elements. The resilience of many of these interactions may be key to minimal loss of visual function in aging; yet many of them remain poorly understood. In this review, we focus on the relation between retinal neurons and their respective mass transport systems. These metabolite delivery systems include the retinal vasculature, which lies within the inner portion of the retina, and the choroidal vasculature located externally to the retinal tissue. A framework for investigation is proposed and applied to identify the structures and processes determining retinal mass transport at the cellular and tissue levels. Spatial variability in the structure of the retina and changes observed in aging are then harnessed to explore the relation between variations in neuron populations and those seen among retinal metabolite delivery systems. Existing data demonstrate that the relation between inner retinal neurons and their mass transport systems is different in nature from that observed between the outer retina and choroid. The most prominent structural changes observed across the eye and in aging are seen in Bruch’s membrane, which forms a selective barrier to mass transfers at the interface between the choroidal vasculature and the outer retina.
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21
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Kim TH, Ding J, Yao X. Intrinsic signal optoretinography of dark adaptation kinetics. Sci Rep 2022; 12:2475. [PMID: 35169239 PMCID: PMC8847457 DOI: 10.1038/s41598-022-06562-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 02/02/2022] [Indexed: 12/13/2022] Open
Abstract
Delayed dark adaptation due to impaired rod photoreceptor homeostasis has been reported as the earliest symptom of eye diseases such as age-related macular degeneration, diabetic retinopathy, and retinitis pigmentosa. Objective measurement of dark adaptation can facilitate early diagnosis to enable prompt intervention to prevent vision loss. However, there is a lack of noninvasive methods capable of spatiotemporal monitoring of photoreceptor changes during dark adaptation. Here we demonstrate functional optical coherence tomography (OCT) for in vivo intrinsic signal optoretinography (ORG) of dark adaptation kinetics in the C57BL/6J mouse retina. Functional OCT revealed a shortening of the outer retina, a rearrangement of the cone and rod photoreceptor interdigitation zone, and a reduction in intrinsic signal amplitude at the photoreceptor inner segment ellipsoid (ISe). A strong positive correlation between the outer retinal shortening and ISe intensity reduction was also confirmed. Functional OCT of dark adaptation kinetics promises an objective method for rapid ORG assessment of physiological integrity of retinal photoreceptors.
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Affiliation(s)
- Tae-Hoon Kim
- Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Jie Ding
- Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Xincheng Yao
- Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA.
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, 60612, USA.
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22
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Baraas RC, Pedersen HR, Knoblauch K, Gilson SJ. Human Foveal Cone and RPE Cell Topographies and Their Correspondence With Foveal Shape. Invest Ophthalmol Vis Sci 2022; 63:8. [PMID: 35113142 PMCID: PMC8819292 DOI: 10.1167/iovs.63.2.8] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Purpose To characterize the association between foveal shape and cone and retinal pigment epithelium (RPE) cell topographies in healthy humans. Methods Multimodal adaptive scanning light ophthalmoscopy and optical coherence tomography (OCT) were used to acquire images of foveal cones, RPE cells, and retinal layers in eyes of 23 healthy participants with normal foveas. Distributions of cone and RPE cell densities were fitted with nonlinear mixed-effects models. A linear mixed-effects model was used to examine the relationship between cone and RPE inter-cell distances and foveal shape as obtained from the OCT scans of retinal thickness. Results The best-fit model to the cone densities was a power function with a nasal–temporal asymmetry. There was a significant linear relationship among cone and RPE cell spacing, foveal shape, and foveal cell topography. The model predictions of the central 10° show that the contributions of both the cones and RPE cells are necessary to account for foveal shape. Conclusions The results indicate that there is a strong relationship between cone and RPE cell spacing and the shape of the human adolescent and adult fovea. This finding adds to the existing evidence of the critical role that the RPE serves in fetal foveal development and through adolescence, possibly via the imposition of constraints on the number and distribution of foveal cones.
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Affiliation(s)
- Rigmor C Baraas
- National Centre for Optics, Vision and Eye Care, Faculty of Health and Social Sciences, University of South-Eastern Norway, Kongsberg, Norway
| | - Hilde R Pedersen
- National Centre for Optics, Vision and Eye Care, Faculty of Health and Social Sciences, University of South-Eastern Norway, Kongsberg, Norway
| | - Kenneth Knoblauch
- National Centre for Optics, Vision and Eye Care, Faculty of Health and Social Sciences, University of South-Eastern Norway, Kongsberg, Norway.,Stem Cell and Brain Research Institute, INSERM U1208, Bron, France.,Université de Lyon, Lyon, France
| | - Stuart J Gilson
- National Centre for Optics, Vision and Eye Care, Faculty of Health and Social Sciences, University of South-Eastern Norway, Kongsberg, Norway
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Brunner E, Shatokhina J, Shirazi MF, Drexler W, Leitgeb R, Pollreisz A, Hitzenberger CK, Ramlau R, Pircher M. Retinal adaptive optics imaging with a pyramid wavefront sensor. BIOMEDICAL OPTICS EXPRESS 2021; 12:5969-5990. [PMID: 34745716 PMCID: PMC8548025 DOI: 10.1364/boe.438915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 08/04/2021] [Indexed: 05/25/2023]
Abstract
The pyramid wavefront sensor (P-WFS) has replaced the Shack-Hartmann (SH-) WFS as the sensor of choice for high-performance adaptive optics (AO) systems in astronomy. Many advantages of the P-WFS, such as its adjustable pupil sampling and superior sensitivity, are potentially of great benefit for AO-supported imaging in ophthalmology as well. However, so far no high quality ophthalmic AO imaging was achieved using this novel sensor. Usually, a P-WFS requires modulation and high precision optics that lead to high complexity and costs of the sensor. These factors limit the competitiveness of the P-WFS with respect to other WFS devices for AO correction in visual science. Here, we present a cost-effective realization of AO correction with a non-modulated P-WFS based on standard components and apply this technique to human retinal in vivo imaging using optical coherence tomography (OCT). P-WFS based high quality AO imaging was successfully performed in 5 healthy subjects and smallest retinal cells such as central foveal cone photoreceptors are visualized. The robustness and versatility of the sensor is demonstrated in the model eye under various conditions and in vivo by high-resolution imaging of other structures in the retina using standard and extended fields of view. As a quality benchmark, the performance of conventional SH-WFS based AO was used and successfully met. This work may trigger a paradigm shift with respect to the wavefront sensor of choice for AO in ophthalmic imaging.
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Affiliation(s)
- Elisabeth Brunner
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria
| | - Julia Shatokhina
- Johann Radon Institute for Computational and Applied Mathematics, Altenbergerstrasse 69, A-4040 Linz, Austria
| | - Muhammad Faizan Shirazi
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria
| | - Wolfgang Drexler
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria
| | - Rainer Leitgeb
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria
| | - Andreas Pollreisz
- Department of Ophthalmology and Optometry, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria
| | - Christoph K. Hitzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria
| | - Ronny Ramlau
- Johann Radon Institute for Computational and Applied Mathematics, Altenbergerstrasse 69, A-4040 Linz, Austria
- Johannes Kepler University Linz, Industrial Mathematics Institute, Altenbergerstrasse 69, A-4040 Linz, Austria
| | - Michael Pircher
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria
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24
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Pandiyan VP, Jiang X, Kuchenbecker JA, Sabesan R. Reflective mirror-based line-scan adaptive optics OCT for imaging retinal structure and function. BIOMEDICAL OPTICS EXPRESS 2021; 12:5865-5880. [PMID: 34692221 PMCID: PMC8515964 DOI: 10.1364/boe.436337] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/16/2021] [Accepted: 08/20/2021] [Indexed: 05/06/2023]
Abstract
Line-scan OCT incorporated with adaptive optics (AO) offers high resolution, speed, and sensitivity for imaging retinal structure and function in vivo. Here, we introduce its implementation with reflective mirror-based afocal telescopes, optimized for imaging light-induced retinal activity (optoretinography) and weak retinal reflections at the cellular scale. A non-planar optical design was followed based on previous recommendations with key differences specific to a line-scan geometry. The three beam paths fundamental to an OCT system -illumination/sample, detection, and reference- were modeled in Zemax optical design software to yield theoretically diffraction-limited performance over a 2.2 deg. field-of-view and 1.5 D vergence range at the eye's pupil. The performance for imaging retinal structure was exemplified by cellular-scale visualization of retinal ganglion cells, macrophages, foveal cones, and rods in human observers. The performance for functional imaging was exemplified by resolving the light-evoked optical changes in foveal cone photoreceptors where the spatial resolution was sufficient for cone spectral classification at an eccentricity 0.3 deg. from the foveal center. This enabled the first in vivo demonstration of reduced S-cone (short-wavelength cone) density in the human foveola, thus far observed only in ex vivo histological preparations. Together, the feasibility for high resolution imaging of retinal structure and function demonstrated here holds significant potential for basic science and translational applications.
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Affiliation(s)
- Vimal Prabhu Pandiyan
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA 98109, USA
- Co-first authors with equal contribution
| | - Xiaoyun Jiang
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA 98109, USA
- Co-first authors with equal contribution
| | - James A Kuchenbecker
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA 98109, USA
| | - Ramkumar Sabesan
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA 98109, USA
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25
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Cideciyan AV, Krishnan AK, Roman AJ, Sumaroka A, Swider M, Jacobson SG. Measures of Function and Structure to Determine Phenotypic Features, Natural History, and Treatment Outcomes in Inherited Retinal Diseases. Annu Rev Vis Sci 2021; 7:747-772. [PMID: 34255540 DOI: 10.1146/annurev-vision-032321-091738] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Inherited retinal diseases (IRDs) are at the forefront of innovative gene-specific treatments because of the causation by single genes, the availability of microsurgical access for treatment delivery, and the relative ease of quantitative imaging and vision measurement. However, it is not always easy to choose a priori, from scores of potential measures, an appropriate subset to evaluate efficacy outcomes considering the wide range of disease stages with different phenotypic features. This article reviews measurements of visual function and retinal structure that our group has used over the past three decades to understand the natural history of IRDs. We include measures of light sensitivity, retinal structure, mapping of natural fluorophores, evaluation of pupillary light reflex, and oculomotor control. We provide historical context and examples of applicability. We also review treatment trial outcomes using these measures of function and structure. Expected final online publication date for the Annual Review of Vision Science, Volume 7 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Artur V Cideciyan
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA;
| | - Arun K Krishnan
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA;
| | - Alejandro J Roman
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA;
| | - Alexander Sumaroka
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA;
| | - Malgorzata Swider
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA;
| | - Samuel G Jacobson
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA;
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26
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Zhang T, Kho AM, Yiu G, Srinivasan VJ. Visible Light Optical Coherence Tomography (OCT) Quantifies Subcellular Contributions to Outer Retinal Band 4. Transl Vis Sci Technol 2021; 10:30. [PMID: 34003965 PMCID: PMC7998011 DOI: 10.1167/tvst.10.3.30] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Purpose To use visible light optical coherence tomography (OCT) to investigate subcellular reflectivity contributions to the outermost (4th) of the retinal hyperreflective bands visualized by current clinical near-infrared (NIR) OCT. Methods Visible light OCT, with 1.0 µm axial resolution, was performed in 28 eyes of 19 human subjects (21–57 years old) without history of ocular pathology. Two foveal and three extrafoveal hyperreflective zones were consistently depicted within band 4 in all eyes. The two outermost hyperreflective bands, occasionally visualized by NIR OCT, were presumed to be the retinal pigment epithelium (RPE) and Bruch's membrane (BM). RPE thickness, BM thickness, and RPE interior reflectivity were quantified topographically across the macula. Results A method for correcting RPE multiple scattering tails was found to both improve the Gaussian goodness-of-fit for the BM intensity profile and reduce the coefficient of variation of BM thickness in vivo. No major topographical differences in macular BM thickness were noted. RPE thickness decreased with increasing eccentricity. Visible light OCT signal intensity in the RPE was weighted to the apical side and attenuated more across the RPE in the fovea than peripherally. Conclusions Morphometry of the presumed RPE and BM bands is consistent with known anatomy. Weighting of RPE reflectivity toward the apical side suggests that melanosomes are the predominant contributors to RPE backscattering and signal attenuation in young eyes. Translational Relevance By enabling morphometric analysis of the RPE and BM, visible light OCT deciphers the main reflectivity contributions to outer retinal band 4, commonly visualized by commercial OCT systems.
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Affiliation(s)
- Tingwei Zhang
- Department of Biomedical Engineering, University of California Davis, Davis, California, USA
| | - Aaron M Kho
- Department of Biomedical Engineering, University of California Davis, Davis, California, USA
| | - Glenn Yiu
- Department of Ophthalmology and Vision Science, University of California Davis, Davis School of Medicine, Sacramento, California, USA
| | - Vivek J Srinivasan
- Department of Biomedical Engineering, University of California Davis, Davis, California, USA.,Department of Ophthalmology and Vision Science, University of California Davis, Davis School of Medicine, Sacramento, California, USA.,Department of Ophthalmology, New York University Langone Health, New York, New York, USA.,Department of Radiology, New York University Langone Health, New York, New York, USA.,Tech4Health Institute, New York University Langone Health, New York, New York, USA
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27
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Armento A, Ueffing M, Clark SJ. The complement system in age-related macular degeneration. Cell Mol Life Sci 2021; 78:4487-4505. [PMID: 33751148 PMCID: PMC8195907 DOI: 10.1007/s00018-021-03796-9] [Citation(s) in RCA: 104] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 02/05/2021] [Accepted: 02/19/2021] [Indexed: 12/13/2022]
Abstract
Age-related macular degeneration (AMD) is a chronic and progressive degenerative disease of the retina, which culminates in blindness and affects mainly the elderly population. AMD pathogenesis and pathophysiology are incredibly complex due to the structural and cellular complexity of the retina, and the variety of risk factors and molecular mechanisms that contribute to disease onset and progression. AMD is driven by a combination of genetic predisposition, natural ageing changes and lifestyle factors, such as smoking or nutritional intake. The mechanism by which these risk factors interact and converge towards AMD are not fully understood and therefore drug discovery is challenging, where no therapeutic attempt has been fully effective thus far. Genetic and molecular studies have identified the complement system as an important player in AMD. Indeed, many of the genetic risk variants cluster in genes of the alternative pathway of the complement system and complement activation products are elevated in AMD patients. Nevertheless, attempts in treating AMD via complement regulators have not yet been successful, suggesting a level of complexity that could not be predicted only from a genetic point of view. In this review, we will explore the role of complement system in AMD development and in the main molecular and cellular features of AMD, including complement activation itself, inflammation, ECM stability, energy metabolism and oxidative stress.
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Affiliation(s)
- Angela Armento
- Department for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Marius Ueffing
- Department for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls University of Tübingen, Tübingen, Germany.
- Department for Ophthalmology, University Eye Clinic, Eberhard Karls University of Tübingen, Tübingen, Germany.
| | - Simon J Clark
- Department for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls University of Tübingen, Tübingen, Germany.
- Department for Ophthalmology, University Eye Clinic, Eberhard Karls University of Tübingen, Tübingen, Germany.
- Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
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28
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Li H, Yu H, Kim YK, Wang F, Teodoro G, Jiang Y, Nickerson JM, Kong J. Computational Model-Based Estimation of Mouse Eyeball Structure From Two-Dimensional Flatmount Microscopy Images. Transl Vis Sci Technol 2021; 10:25. [PMID: 34004004 PMCID: PMC8088229 DOI: 10.1167/tvst.10.4.25] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 02/17/2021] [Indexed: 11/25/2022] Open
Abstract
Purpose Retinal pigment epithelial (RPE) cells serve as a supporter for the metabolism and visual function of photoreceptors and a barrier for photoreceptor protection. Morphology dynamics, spatial organization, distribution density, and growth patterns of RPE cells are important for further research on these RPE main functions. To enable such investigations within the authentic eyeball structure, a new method for estimating the three-dimensional (3D) eyeball sphere from two-dimensional tissue flatmount microscopy images was investigated. Methods An error-correction term was formulated to compensate for the reconstruction error as a result of tissue distortions. The effect of the tissue-distortion error was evaluated by excluding partial data points from the low- and high-latitude zones. The error-correction parameter was learned automatically using a set of samples with the ground truth eyeball diameters measured with noncontact light-emitting diode micrometry at submicron accuracy and precision. Results The analysis showed that the error-correction term in the reconstruction model is a valid method for modeling tissue distortions in the tissue flatmount preparation steps. With the error-correction model, the average relative error of the estimated eyeball diameter was reduced from 14% to 5%, and the absolute error was reduced from 0.22 to 0.03 mm. Conclusions A new method for enabling RPE morphometry analysis with respect to locations on an eyeball sphere was created, an important step in increasing RPE research and eye disease diagnosis. Translational Relevance This method enables one to derive RPE cell information from the 3D eyeball surface and helps characterize eyeball volume growth patterns under diseased conditions.
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Affiliation(s)
- Hongxiao Li
- Department of Mathematics and Statistics, Georgia State University, Atlanta, GA, USA
- Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
| | - Hanyi Yu
- Department of Computer Science, Emory University, Atlanta, GA, USA
| | - Yong-Kyu Kim
- Department of Ophthalmology, Hallym University College of Medicine, Kangdong Sacred Heart Hospital, Seoul, South Korea
| | - Fusheng Wang
- Department of Computer Science, Stony Brook University, Stony Brook, NY, USA
| | - George Teodoro
- Department of Computer Science, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Yi Jiang
- Department of Mathematics and Statistics, Georgia State University, Atlanta, GA, USA
| | | | - Jun Kong
- Department of Mathematics and Statistics, Georgia State University, Atlanta, GA, USA
- Department of Computer Science, Emory University, Atlanta, GA, USA
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29
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Li J, Liu T, Flynn OJ, Turriff A, Liu Z, Ullah E, Liu J, Dubra A, Johnson MA, Brooks BP, Hufnagel RB, Hammer DX, Huryn LA, Jeffrey BG, Tam J. Persistent Dark Cones in Oligocone Trichromacy Revealed by Multimodal Adaptive Optics Ophthalmoscopy. Front Aging Neurosci 2021; 13:629214. [PMID: 33767618 PMCID: PMC7985087 DOI: 10.3389/fnagi.2021.629214] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 02/09/2021] [Indexed: 11/13/2022] Open
Abstract
Dark cone photoreceptors, defined as those with diminished or absent reflectivity when observed with adaptive optics (AO) ophthalmoscopy, are increasingly reported in retinal disorders. However, their structural and functional impact remain unclear. Here, we report a 3-year longitudinal study on a patient with oligocone trichromacy (OT) who presented with persistent, widespread dark cones within and near the macula. Diminished electroretinogram (ERG) cone but normal ERG rod responses together with normal color vision confirmed the OT diagnosis. In addition, the patient had normal to near normal visual acuity and retinal sensitivity. Occasional dark gaps in the photoreceptor layer were observed on optical coherence tomography, in agreement with reflectance AO scanning light ophthalmoscopy, which revealed that over 50% of the cones in the fovea were dark, increasing to 74% at 10° eccentricity. In addition, the cone density was 78% lower than normal histologic value at the fovea, and 20-40% lower at eccentricities of 5-15°. Interestingly, color vision testing was near normal at locations where cones were predominantly dark. These findings illustrate how a retina with predominant dark cones that persist over at least 3 years can support near normal central retinal function. Furthermore, this study adds to the growing evidence that cones can continue to survive under non-ideal conditions.
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Affiliation(s)
- Joanne Li
- National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Tao Liu
- National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Oliver J Flynn
- National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Amy Turriff
- National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Zhuolin Liu
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD, United States
| | - Ehsan Ullah
- National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Jianfei Liu
- National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Alfredo Dubra
- Department of Ophthalmology, Stanford University, Palo Alto, CA, Unites States
| | - Mary A Johnson
- Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Brian P Brooks
- National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Robert B Hufnagel
- National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Daniel X Hammer
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD, United States
| | - Laryssa A Huryn
- National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Brett G Jeffrey
- National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Johnny Tam
- National Eye Institute, National Institutes of Health, Bethesda, MD, United States
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30
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Bower AJ, Liu T, Aguilera N, Li J, Liu J, Lu R, Giannini JP, Huryn LA, Dubra A, Liu Z, Hammer DX, Tam J. Integrating adaptive optics-SLO and OCT for multimodal visualization of the human retinal pigment epithelial mosaic. BIOMEDICAL OPTICS EXPRESS 2021; 12:1449-1466. [PMID: 33796365 PMCID: PMC7984802 DOI: 10.1364/boe.413438] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 01/29/2021] [Accepted: 01/31/2021] [Indexed: 05/03/2023]
Abstract
In vivo imaging of human retinal pigment epithelial (RPE) cells has been demonstrated through multiple adaptive optics (AO)-based modalities. However, whether consistent and complete information regarding the cellular structure of the RPE mosaic is obtained across these modalities remains uncertain due to limited comparisons performed in the same eye. Here, an imaging platform combining multimodal AO-scanning light ophthalmoscopy (AO-SLO) with AO-optical coherence tomography (AO-OCT) is developed to make a side-by-side comparison of the same RPE cells imaged across four modalities: AO-darkfield, AO-enhanced indocyanine green (AO-ICG), AO-infrared autofluorescence (AO-IRAF), and AO-OCT. Co-registered images were acquired in five subjects, including one patient with choroideremia. Multimodal imaging provided multiple perspectives of the RPE mosaic that were used to explore variations in RPE cell contrast in a subject-, location-, and even cell-dependent manner. Estimated cell-to-cell spacing and density were found to be consistent both across modalities and with normative data. Multimodal images from a patient with choroideremia illustrate the benefit of using multiple modalities to infer the cellular structure of the RPE mosaic in an affected eye, in which disruptions to the RPE mosaic may locally alter the signal strength, visibility of individual RPE cells, or even source of contrast in unpredictable ways.
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Affiliation(s)
- Andrew J. Bower
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tao Liu
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nancy Aguilera
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Joanne Li
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jianfei Liu
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Rongwen Lu
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - John P. Giannini
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Laryssa A. Huryn
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Alfredo Dubra
- Department of Ophthalmology, Stanford University, Palo Alto, CA 94303, USA
| | - Zhuolin Liu
- Center for Devices and Radiological Health (CDRH), U.S. Food and Drug Administration, 10903 New Hampshire Ave, Silver Spring, MD 20993, USA
| | - Daniel X. Hammer
- Center for Devices and Radiological Health (CDRH), U.S. Food and Drug Administration, 10903 New Hampshire Ave, Silver Spring, MD 20993, USA
| | - Johnny Tam
- National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
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31
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Kurokawa K, Crowell JA, Do N, Lee JJ, Miller DT. Multi-reference global registration of individual A-lines in adaptive optics optical coherence tomography retinal images. JOURNAL OF BIOMEDICAL OPTICS 2021; 26:JBO-200266R. [PMID: 33410310 PMCID: PMC7787477 DOI: 10.1117/1.jbo.26.1.016001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 12/10/2020] [Indexed: 05/18/2023]
Abstract
SIGNIFICANCE Adaptive optics optical coherence tomography (AO-OCT) technology enables non-invasive, high-resolution three-dimensional (3D) imaging of the retina and promises earlier detection of ocular disease. However, AO-OCT data are corrupted by eye-movement artifacts that must be removed in post-processing, a process rendered time-consuming by the immense quantity of data. AIM To efficiently remove eye-movement artifacts at the level of individual A-lines, including those present in any individual reference volume. APPROACH We developed a registration method that cascades (1) a 3D B-scan registration algorithm with (2) a global A-line registration algorithm for correcting torsional eye movements and image scaling and generating global motion-free coordinates. The first algorithm corrects 3D translational eye movements to a single reference volume, accelerated using parallel computing. The second algorithm combines outputs of multiple runs of the first algorithm using different reference volumes followed by an affine transformation, permitting registration of all images to a global coordinate system at the level of individual A-lines. RESULTS The 3D B-scan algorithm estimates and corrects 3D translational motions with high registration accuracy and robustness, even for volumes containing microsaccades. Averaging registered volumes improves our image quality metrics up to 22 dB. Implementation in CUDA™ on a graphics processing unit registers a 512 × 512 × 512 volume in only 10.6 s, 150 times faster than MATLAB™ on a central processing unit. The global A-line algorithm minimizes image distortion, improves regularity of the cone photoreceptor mosaic, and supports enhanced visualization of low-contrast retinal cellular features. Averaging registered volumes improves our image quality up to 9.4 dB. It also permits extending the imaging field of view (∼2.1 × ) and depth of focus (∼5.6 × ) beyond what is attainable with single-reference registration. CONCLUSIONS We can efficiently correct eye motion in all 3D at the level of individual A-lines using a global coordinate system.
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Affiliation(s)
- Kazuhiro Kurokawa
- Indiana University, School of Optometry, Bloomington, Indiana, United States
| | - James A. Crowell
- Indiana University, School of Optometry, Bloomington, Indiana, United States
| | - Nhan Do
- Purdue School of Engineering and Technology, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana, United States
- Google, Mountain View, California, United States
| | - John J. Lee
- Purdue School of Engineering and Technology, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana, United States
| | - Donald T. Miller
- Indiana University, School of Optometry, Bloomington, Indiana, United States
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Liu J, Han YJ, Liu T, Aguilera N, Tam J. Spatially Aware Dense-LinkNet Based Regression Improves Fluorescent Cell Detection in Adaptive Optics Ophthalmic Images. IEEE J Biomed Health Inform 2020; 24:3520-3528. [PMID: 32750947 DOI: 10.1109/jbhi.2020.3004271] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Retinal pigment epithelial (RPE) cells play an important role in nourishing retinal neurosensory photoreceptor cells, and numerous blinding diseases are associated with RPE defects. Their fluorescence signature can now be visualized in the living human eye using adaptive optics (AO) imaging combined with indocyanine green (ICG), which motivates us to develop an automated RPE detection method to improve the quantitative evaluation of RPE status in patients. This paper proposes a spatially-aware, Dense-LinkNet-based regression approach to improve the detection of in vivo fluorescent cell patterns, achieving precision, recall, and F1-Score of 93.6 ± 4.3%, 81.4 ± 9.5%, and 86.7 ± 5.7%, respectively. These results demonstrate the utility of incorporating spatial inputs into a deep learning-based regression framework for cell detection.
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Wynne N, Carroll J, Duncan JL. Promises and pitfalls of evaluating photoreceptor-based retinal disease with adaptive optics scanning light ophthalmoscopy (AOSLO). Prog Retin Eye Res 2020; 83:100920. [PMID: 33161127 DOI: 10.1016/j.preteyeres.2020.100920] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 10/28/2020] [Accepted: 10/31/2020] [Indexed: 12/15/2022]
Abstract
Adaptive optics scanning light ophthalmoscopy (AOSLO) allows visualization of the living human retina with exquisite single-cell resolution. This technology has improved our understanding of normal retinal structure and revealed pathophysiological details of a number of retinal diseases. Despite the remarkable capabilities of AOSLO, it has not seen the widespread commercial adoption and mainstream clinical success of other modalities developed in a similar time frame. Nevertheless, continued advancements in AOSLO hardware and software have expanded use to a broader range of patients. Current devices enable imaging of a number of different retinal cell types, with recent improvements in stimulus and detection schemes enabling monitoring of retinal function, microscopic structural changes, and even subcellular activity. This has positioned AOSLO for use in clinical trials, primarily as exploratory outcome measures or biomarkers that can be used to monitor disease progression or therapeutic response. AOSLO metrics could facilitate patient selection for such trials, to refine inclusion criteria or to guide the choice of therapy, depending on the presence, absence, or functional viability of specific cell types. Here we explore the potential of AOSLO retinal imaging by reviewing clinical applications as well as some of the pitfalls and barriers to more widespread clinical adoption.
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Affiliation(s)
- Niamh Wynne
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Joseph Carroll
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Jacque L Duncan
- Department of Ophthalmology, University of California, San Francisco, CA, USA.
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Rudraraju M, Narayanan SP, Somanath PR. Regulation of blood-retinal barrier cell-junctions in diabetic retinopathy. Pharmacol Res 2020; 161:105115. [PMID: 32750417 PMCID: PMC7755666 DOI: 10.1016/j.phrs.2020.105115] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 07/22/2020] [Accepted: 07/27/2020] [Indexed: 12/15/2022]
Abstract
Loss of the blood-retinal barrier (BRB) integrity and subsequent damage to the neurovascular unit in the retina are the underlying reasons for diabetic retinopathy (DR). Damage to BRB eventually leads to severe visual impairment in the absence of prompt intervention. Diabetic macular edema and proliferative DR are the advanced stages of the disease where BRB integrity is altered. Primary mechanisms contributing to BRB dysfunction include loss of cell-cell barrier junctions, vascular endothelial growth factor, advanced glycation end products-induced damage, and oxidative stress. Although much is known about the involvement of adherens and tight-junction proteins in the regulation of vascular permeability in various diseases, there is a significant gap in our knowledge on the junctional proteins expressed in the BRB and how BRB function is modulated in the diabetic retina. In this review article, we present our current understanding of the molecular composition of BRB, the changes in the BRB junctional protein turnover in DR, and how BRB functional modulation affects vascular permeability and macular edema in the diabetic retina.
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Affiliation(s)
- Madhuri Rudraraju
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia and Charlie Norwood VA Medical Center, Augusta, GA 30912, United States; James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA 30912, United States
| | - S Priya Narayanan
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia and Charlie Norwood VA Medical Center, Augusta, GA 30912, United States; Vascular Biology Center, Augusta University, Augusta, GA 30912, United States; James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA 30912, United States
| | - Payaningal R Somanath
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia and Charlie Norwood VA Medical Center, Augusta, GA 30912, United States; Vascular Biology Center, Augusta University, Augusta, GA 30912, United States; Department of Medicine, Augusta University, Augusta, GA 30912, United States.
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Zhang T, Kho AM, Zawadzki RJ, Jonnal RS, Yiu G, Srinivasan VJ. Visible light OCT improves imaging through a highly scattering retinal pigment epithelial wall. OPTICS LETTERS 2020; 45:5945-5948. [PMID: 33137037 PMCID: PMC7864585 DOI: 10.1364/ol.405398] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 09/21/2020] [Indexed: 05/15/2023]
Abstract
Here we provide a counter-example to the conventional wisdom in biomedical optics that longer wavelengths aid deeper imaging in tissue. Specifically, we investigate visible light optical coherence tomography of Bruch's membrane (BM) in the non-pathologic eyes of humans and two mouse strains. Surprisingly, we find that shorter visible wavelengths improve the visualization of BM in pigmented eyes, where it is located behind a highly scattering layer of melanosomes in the retinal pigment epithelium (RPE). Monte Carlo simulations of radiative transport suggest that, while absorption and scattering are higher at shorter wavelengths, detected multiply scattered light from the RPE is preferentially attenuated relative to detected backscattered light from the BM.
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Affiliation(s)
- Tingwei Zhang
- Department of Biomedical Engineering, University of California Davis, Davis, California 95616, USA
| | - Aaron M. Kho
- Department of Biomedical Engineering, University of California Davis, Davis, California 95616, USA
| | - Robert J. Zawadzki
- Department of Ophthalmology and Vision Science, University of California Davis, Davis School of Medicine, Sacramento, California 96817, USA
| | - Ravi S. Jonnal
- Department of Ophthalmology and Vision Science, University of California Davis, Davis School of Medicine, Sacramento, California 96817, USA
| | - Glenn Yiu
- Department of Ophthalmology and Vision Science, University of California Davis, Davis School of Medicine, Sacramento, California 96817, USA
| | - Vivek J. Srinivasan
- Department of Biomedical Engineering, University of California Davis, Davis, California 95616, USA
- Department of Ophthalmology and Vision Science, University of California Davis, Davis School of Medicine, Sacramento, California 96817, USA
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36
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Miller DT, Kurokawa K. Cellular-Scale Imaging of Transparent Retinal Structures and Processes Using Adaptive Optics Optical Coherence Tomography. Annu Rev Vis Sci 2020; 6:115-148. [PMID: 32609578 PMCID: PMC7864592 DOI: 10.1146/annurev-vision-030320-041255] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
High-resolution retinal imaging is revolutionizing how scientists and clinicians study the retina on the cellular scale. Its exquisite sensitivity enables time-lapse optical biopsies that capture minute changes in the structure and physiological processes of cells in the living eye. This information is increasingly used to detect disease onset and monitor disease progression during early stages, raising the possibility of personalized eye care. Powerful high-resolution imaging tools have been in development for more than two decades; one that has garnered considerable interest in recent years is optical coherence tomography enhanced with adaptive optics. State-of-the-art adaptive optics optical coherence tomography (AO-OCT) makes it possible to visualize even highly transparent cells and measure some of their internal processes at all depths within the retina, permitting reconstruction of a 3D view of the living microscopic retina. In this review, we report current AO-OCT performance and its success in visualizing and quantifying these once-invisible cells in human eyes.
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Affiliation(s)
- Donald T Miller
- School of Optometry, Indiana University, Bloomington, Indiana 47405, USA; ,
| | - Kazuhiro Kurokawa
- School of Optometry, Indiana University, Bloomington, Indiana 47405, USA; ,
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Mecê P, Gofas-Salas E, Paques M, Grieve K, Meimon S. Optical Incoherence Tomography: a method to generate tomographic retinal cross-sections with non-interferometric adaptive optics ophthalmoscopes. BIOMEDICAL OPTICS EXPRESS 2020; 11:4069-4084. [PMID: 32923029 PMCID: PMC7449754 DOI: 10.1364/boe.396937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/12/2020] [Accepted: 06/16/2020] [Indexed: 05/05/2023]
Abstract
We present Optical Incoherence Tomography (OIT): a completely digital method to generate tomographic retinal cross-sections from en-face through-focus image stacks acquired by non-interferometric imaging systems, such as en-face adaptive optics (AO)-ophthalmoscopes. We demonstrate that OIT can be applied to different imaging modalities using back-scattered light, including systems without inherent optical sectioning and, for the first time, multiply-scattered light, revealing a distinctive cross-sectional view of the retina. The axial dimension of OIT cross-sections is given in terms of focus position rather than optical path, as in OCT. We explore this property to guide focus position in cases where the user is "blind" focusing, allowing precise plane selection for en-face imaging of retinal pigment epithelium, the vascular plexuses and translucent retinal neurons, such as photoreceptor inner segments and retinal ganglion cells, using respectively autofluorescence, motion contrast and split detection techniques.
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Affiliation(s)
- Pedro Mecê
- Institut Langevin, ESPCI Paris, CNRS, PSL University, 1 rue Jussieu, 75005 Paris, France
| | - Elena Gofas-Salas
- Quinze-Vingts National Eye Hospital, 28 Rue de Charenton, Paris, 75012, France
| | - Michel Paques
- Quinze-Vingts National Eye Hospital, 28 Rue de Charenton, Paris, 75012, France
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, F-75012, Paris, France
| | - Kate Grieve
- Quinze-Vingts National Eye Hospital, 28 Rue de Charenton, Paris, 75012, France
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, F-75012, Paris, France
| | - Serge Meimon
- DOTA, ONERA, Université Paris Saclay F-91123 Palaiseau, France
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Shirazi MF, Brunner E, Laslandes M, Pollreisz A, Hitzenberger CK, Pircher M. Visualizing human photoreceptor and retinal pigment epithelium cell mosaics in a single volume scan over an extended field of view with adaptive optics optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2020; 11:4520-4535. [PMID: 32923061 PMCID: PMC7449740 DOI: 10.1364/boe.393906] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 07/13/2020] [Accepted: 07/17/2020] [Indexed: 05/18/2023]
Abstract
Using adaptive optics optical coherence tomography, human photoreceptors and retinal pigment epithelium (RPE) cells are typically visualized on a small field of view of ∼1° to 2°. In addition, volume averaging is required for visualizing the RPE cell mosaic. To increase the imaging area, we introduce a lens based spectral domain AO-OCT system that shows low aberrations within an extended imaging area of 4°×4° while maintaining a high (theoretical) transverse resolution (at >7 mm pupil diameter) in the order of 2 µm. A new concept for wavefront sensing is introduced that uses light mainly originating from the RPE layer and yields images of the RPE cell mosaic in a single volume acquisition. The capability of the instrument for in vivo imaging is demonstrated by visualizing various cell structures within the posterior retinal layers over an extended field of view.
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Affiliation(s)
- Muhammad Faizan Shirazi
- Center for Medical Physics and Biomedical
Engineering, Medical University of Vienna, Waehringer Guertel 18-20,
A-1090 Vienna, Austria
| | - Elisabeth Brunner
- Center for Medical Physics and Biomedical
Engineering, Medical University of Vienna, Waehringer Guertel 18-20,
A-1090 Vienna, Austria
| | - Marie Laslandes
- ALPAO 727 rue Aristide Bergès 38330
Montbonnot-Saint-Martin, France
| | - Andreas Pollreisz
- Department of Ophthalmology and Optometry,
Medical University of Vienna, Vienna, Waehringer Guertel 18-20, A-1090
Vienna, Austria
| | - Christoph K. Hitzenberger
- Center for Medical Physics and Biomedical
Engineering, Medical University of Vienna, Waehringer Guertel 18-20,
A-1090 Vienna, Austria
| | - Michael Pircher
- Center for Medical Physics and Biomedical
Engineering, Medical University of Vienna, Waehringer Guertel 18-20,
A-1090 Vienna, Austria
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Pollreisz A, Neschi M, Sloan KR, Pircher M, Mittermueller T, Dacey DM, Schmidt-Erfurth U, Curcio CA. Atlas of Human Retinal Pigment Epithelium Organelles Significant for Clinical Imaging. Invest Ophthalmol Vis Sci 2020; 61:13. [PMID: 32648890 PMCID: PMC7425708 DOI: 10.1167/iovs.61.8.13] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Accepted: 04/27/2020] [Indexed: 02/07/2023] Open
Abstract
Purpose To quantify organelles impacting imaging in the cell body and intact apical processes of human retinal pigment epithelium (RPE), including melanosomes, lipofuscin-melanolipofuscin (LM), mitochondria, and nuclei. Methods A normal perifovea of a 21-year-old white male was preserved after rapid organ recovery. An aligned image stack was generated using serial block-face scanning electron microscopy and was annotated by expert readers (TrakEM, ImageJ). Acquired measures included cell body and nuclear volume (n = 17); organelle count in apical processes (n = 17) and cell bodies (n = 8); distance of cell body organelles along a normalized apical-basal axis (n = 8); and dimensions of organelle-bounding boxes in apical processes in selected subsamples of cell bodies and apical processes. Results In 2661 sections through 17 cells, apical processes contained 65 ± 24 melanosomes in mononucleate (n = 15) and 131 ± 28 in binucleate cells (n = 2). Cell bodies contained 681 ± 153 LM and 734 ± 170 mitochondria. LM was excluded from the basal quartile, and mitochondria from the apical quartile. Lengths of melanosomes, LM, and mitochondria, respectively were 2305 ± 528, 1320 ± 574, and 1195 ± 294 nm. The ratio of cell body to nucleus volume was 4.6 ± 0.4. LM and mitochondria covered 75% and 63%, respectively, of the retinal imaging plane. Conclusions Among RPE signal sources for optical coherence tomography, LM and mitochondria are the most numerous reflective cell body organelles. These and our published data show that most melanosomes are in apical processes. Overlapping LM and previously mitochondria cushions may support multiple reflective bands in cell bodies. This atlas of subcellular reflectivity sources can inform development of advanced optical coherence tomography technologies.
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Affiliation(s)
- Andreas Pollreisz
- Department of Ophthalmology, Medical University of Vienna, Vienna, Austria
| | - Martina Neschi
- Department of Ophthalmology, Medical University of Vienna, Vienna, Austria
| | - Kenneth R. Sloan
- Department of Ophthalmology and Visual Sciences, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Department of Computer Science, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Michael Pircher
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | | | - Dennis M. Dacey
- Department of Biologic Structure, University of Washington, Seattle, Washington, United States
| | | | - Christine A. Curcio
- Department of Ophthalmology and Visual Sciences, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
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40
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Laforest T, Künzi M, Kowalczuk L, Carpentras D, Behar-Cohen F, Moser C. Transscleral Optical Phase Imaging of the Human Retina. NATURE PHOTONICS 2020; 14:439-445. [PMID: 32607125 PMCID: PMC7326609 DOI: 10.1038/s41566-020-0608-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In-vivo observation of the human retina at the cellular level is crucial to detect the first signs of retinal diseases and properly treat them. Despite the phenomenal advances in adaptive optics (AO) systems, clinical imaging of many retinal cells is still elusive due to the low signal-to-noise ratio induced by transpupillary illumination. We present a transscleral optical phase imaging (TOPI) method, which relies on high-angle oblique illumination of the retina, combined with AO, to enhance cell contrast. Examination of eleven healthy volunteer eyes, without pupil dilation, shows the ability of this method to produce in-vivo images of retinal cells, from the retinal pigment epithelium to the nerve fibre layer. This method also allows the generation of high-resolution label-free ex-vivo phase images of flat-mounted retinas. The 4.4°x 4.4° field-of-view in-vivo images are recorded in less than 10 seconds, opening new avenues in the exploration of healthy and diseased retinas.
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Affiliation(s)
- T. Laforest
- Laboratory of Applied Photonic Devices (LAPD), School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- EarlySight SA, EPFL Innovation Park, Lausanne, Switzerland
| | - M. Künzi
- Laboratory of Applied Photonic Devices (LAPD), School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- EarlySight SA, EPFL Innovation Park, Lausanne, Switzerland
| | - L. Kowalczuk
- Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
- Jules-Gonin Eye Hospital, Fondation Asile des aveugles, Lausanne, Switzerland
| | - D. Carpentras
- Laboratory of Applied Photonic Devices (LAPD), School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - F. Behar-Cohen
- Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
- Centre de Recherche des Cordeliers, Inserm, USPC, Université de Paris, Sorbonne Université, From physiopathology of ocular diseases to clinical developments, F-75006 Paris, France
- Ophtalmopole, Hôpital Cochin, Assistance Publique Hôpitaux de Paris, Université de Paris, Paris, France
| | - C. Moser
- Laboratory of Applied Photonic Devices (LAPD), School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Materials and Correspondence: Correspondence and requests for materials should be addressed to
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41
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Caetano Dos Santos FL, Laforest T, Künzi M, Kowalczuk L, Behar-Cohen F, Moser C. Fully automated detection, segmentation, and analysis of in vivo RPE single cells. Eye (Lond) 2020; 35:1473-1481. [PMID: 32555522 DOI: 10.1038/s41433-020-1036-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 06/09/2020] [Indexed: 11/09/2022] Open
Abstract
OBJECTIVE To develop a fully automated method of retinal pigmented epithelium (RPE) cells detection, segmentation and analysis based on in vivo cellular resolution images obtained with the transscleral optical phase imaging method (TOPI). METHODS Fourteen TOPI-RPE images from 11 healthy individuals were analysed. The developed image processing method encompassed image filtering and normalisation, detection and removal of blood vessels, cell detection and cell membrane segmentation. The produced measures were cellular density of RPE layer, cell area, number of neighbouring cells, eccentricity, circularity and solidity. In addition, we proposed coefficient of variation (CV) of RPE cellular membrane (CMDCV) and the solidity of the RPE cell membrane-shape as new metrics for the assessment of RPE single cells. RESULTS The observed median cellular density of the RPE layer was 3743 cells/µm2 (interquartile rate (IQR) 1687), with a median observed RPE cell area of 193 µm2 (IQR 141). The mean number of neighbouring cells was 5.22 (standard deviation (SD) 0.05) per RPE cell. The mean RPE cell eccentricity was 0.67 (SD 0.02), median circularity 0.83 (IQR 0.01), and median solidity 0.92 (IQR 0.00). The median CMDCV was 0.19 (IQR 0.02). The method is characterised by a median image processing and analysis time of 48 sec (IQR 12) per image. CONCLUSIONS The present study provides the first fully automated quantitative assessment of human RPE single cells in vivo. The method provides a baseline for future research in the field of clinical ophthalmology, enabling characterisation and diagnostics of retinal diseases at the single-cell level.
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Affiliation(s)
| | - Timothé Laforest
- Laboratory of Applied Photonic Devices (LAPD), School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | | | - Laura Kowalczuk
- Laboratory of Applied Photonic Devices (LAPD), School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.,Department of Ophthalmology, Jules-Gonin Eye Hospital, Fondation Asile des aveugles, University of Lausanne, Lausanne, Switzerland
| | - Francine Behar-Cohen
- INSERM UMR_S 1138, Team 17, Centre de Recherche des Cordeliers, University of Pierre et Marie Curie, Paris Descartes University, Sorbonne Paris Cité, Paris, France.,Department of Ophthalmology, Ophthalmopole, Cochin Hospital, Assistance Publique, Hôpitaux de Paris, Paris, France
| | - Christophe Moser
- Laboratory of Applied Photonic Devices (LAPD), School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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42
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Vienola KV, Zhang M, Snyder VC, Sahel JA, Dansingani KK, Rossi EA. Microstructure of the retinal pigment epithelium near-infrared autofluorescence in healthy young eyes and in patients with AMD. Sci Rep 2020; 10:9561. [PMID: 32533046 PMCID: PMC7293312 DOI: 10.1038/s41598-020-66581-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 05/21/2020] [Indexed: 01/18/2023] Open
Abstract
Retinal pigmented epithelial (RPE) cells are essential for maintaining normal visual function, especially in their role in the visual cycle, and are thought to be one of the first cell classes affected by age-related macular degeneration (AMD). Clinical imaging systems routinely evaluate the structure of the RPE at the tissue level, but cellular level information may provide valuable RPE biomarkers of health, aging and disease. In this exploratory study, participants were imaged with 795 nm excitation in adaptive optics scanning laser ophthalmoscopy (AOSLO) to observe the microstructure of the near-infrared autofluorescence (AO-IRAF) from the RPE layer in healthy retinas and patients with AMD. The expected hexagonal mosaic of RPE cells was only sometimes seen in normal eyes, while AMD patients exhibited highly variable patterns of altered AO-IRAF. In some participants, AO-IRAF structure corresponding to cones was observed, as we have demonstrated previously. In some AMD patients, marked alterations in the pattern of AO-IRAF could be seen even in areas where the RPE appeared relatively normal in clinical imaging modalities, such as spectral domain optical coherence tomography (SD-OCT). AO-IRAF imaging using AOSLO offers promise for better detection and understanding of early RPE changes in the course of AMD, potentially before clinical signs appear.
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Affiliation(s)
- Kari V Vienola
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA.
| | - Min Zhang
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Valerie C Snyder
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - José-Alain Sahel
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Kunal K Dansingani
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Ethan A Rossi
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
- Department of Bioengineering, University of Pittsburgh Swanson School of Engineering, Pittsburgh, PA, 15213, USA
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43
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Lakkaraju A, Umapathy A, Tan LX, Daniele L, Philp NJ, Boesze-Battaglia K, Williams DS. The cell biology of the retinal pigment epithelium. Prog Retin Eye Res 2020; 78:100846. [PMID: 32105772 PMCID: PMC8941496 DOI: 10.1016/j.preteyeres.2020.100846] [Citation(s) in RCA: 185] [Impact Index Per Article: 46.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 02/19/2020] [Accepted: 02/23/2020] [Indexed: 02/07/2023]
Abstract
The retinal pigment epithelium (RPE), a monolayer of post-mitotic polarized epithelial cells, strategically situated between the photoreceptors and the choroid, is the primary caretaker of photoreceptor health and function. Dysfunction of the RPE underlies many inherited and acquired diseases that cause permanent blindness. Decades of research have yielded valuable insight into the cell biology of the RPE. In recent years, new technologies such as live-cell imaging have resulted in major advancement in our understanding of areas such as the daily phagocytosis and clearance of photoreceptor outer segment tips, autophagy, endolysosome function, and the metabolic interplay between the RPE and photoreceptors. In this review, we aim to integrate these studies with an emphasis on appropriate models and techniques to investigate RPE cell biology and metabolism, and discuss how RPE cell biology informs our understanding of retinal disease.
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Affiliation(s)
- Aparna Lakkaraju
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA
| | - Ankita Umapathy
- Department of Ophthalmology and Stein Eye Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Li Xuan Tan
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA
| | - Lauren Daniele
- Department of Biochemistry, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Nancy J Philp
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Kathleen Boesze-Battaglia
- Department of Biochemistry, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David S Williams
- Department of Ophthalmology and Stein Eye Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
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44
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Cuenca N, Ortuño-Lizarán I, Sánchez-Sáez X, Kutsyr O, Albertos-Arranz H, Fernández-Sánchez L, Martínez-Gil N, Noailles A, López-Garrido JA, López-Gálvez M, Lax P, Maneu V, Pinilla I. Interpretation of OCT and OCTA images from a histological approach: Clinical and experimental implications. Prog Retin Eye Res 2020; 77:100828. [PMID: 31911236 DOI: 10.1016/j.preteyeres.2019.100828] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 12/16/2019] [Accepted: 12/30/2019] [Indexed: 12/17/2022]
Abstract
Optical coherence tomography (OCT) and OCT angiography (OCTA) have been a technological breakthrough in the diagnosis, treatment, and follow-up of many retinal diseases, thanks to its resolution and its ability to inform of the retinal state in seconds, which gives relevant information about retinal degeneration. In this review, we present an immunohistochemical description of the human and mice retina and we correlate it with the OCT bands in health and pathological conditions. Here, we propose an interpretation of the four outer hyperreflective OCT bands with a correspondence to retinal histology: the first and innermost band as the external limiting membrane (ELM), the second band as the cone ellipsoid zone (EZ), the third band as the outer segment tips phagocytosed by the pigment epithelium (PhaZ), and the fourth band as the mitochondria in the basal portion of the RPE (RPEmitZ). The integrity of these bands would reflect the health of photoreceptors and retinal pigment epithelium. Moreover, we describe how the vascular plexuses vary in different regions of the healthy human and mice retina, using OCTA and immunohistochemistry. In humans, four, three, two or one plexuses can be observed depending on the distance from the fovea. Also, specific structures such as vascular loops in the intermediate capillary plexus, or spider-like structures of interconnected capillaries in the deep capillary plexus are found. In mice, three vascular plexuses occupy the whole retina, except in the most peripheral retina where only two plexuses are found. These morphological issues should be considered when assessing a pathology, as some retinal diseases are associated with structural changes in blood vessels. Therefore, the analysis of OCT bands and OCTA vascular plexuses may be complementary for the diagnosis and prognosis of retinal degenerative processes, useful to assess therapeutic approaches, and it is usually correlated to visual acuity.
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Affiliation(s)
- Nicolás Cuenca
- Department of Physiology, Genetics and Microbiology, University of Alicante, Spain; Institute Ramón Margalef, University of Alicante, Alicante, Spain.
| | | | - Xavier Sánchez-Sáez
- Department of Physiology, Genetics and Microbiology, University of Alicante, Spain
| | - Oksana Kutsyr
- Department of Physiology, Genetics and Microbiology, University of Alicante, Spain
| | | | | | - Natalia Martínez-Gil
- Department of Physiology, Genetics and Microbiology, University of Alicante, Spain
| | - Agustina Noailles
- Department of Physiology, Genetics and Microbiology, University of Alicante, Spain
| | | | | | - Pedro Lax
- Department of Physiology, Genetics and Microbiology, University of Alicante, Spain
| | - Victoria Maneu
- Department of Optics, Pharmacology and Anatomy, University of Alicante, Spain
| | - Isabel Pinilla
- Department of Ophthalmology, Lozano Blesa, University Hospital, Zaragoza, Spain
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45
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Mastey RR, Georgiou M, Langlo CS, Kalitzeos A, Patterson EJ, Kane T, Singh N, Vincent A, Moore AT, Tsang SH, Lin JH, Young MP, Hartnett ME, Héon E, Kohl S, Michaelides M, Carroll J. Characterization of Retinal Structure in ATF6-Associated Achromatopsia. Invest Ophthalmol Vis Sci 2019; 60:2631-2640. [PMID: 31237654 PMCID: PMC6594318 DOI: 10.1167/iovs.19-27047] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Purpose Mutations in six genes have been associated with achromatopsia (ACHM): CNGA3, CNGB3, PDE6H, PDE6C, GNAT2, and ATF6. ATF6 is the most recent gene to be identified, though thorough phenotyping of this genetic subtype is lacking. Here, we sought to test the hypothesis that ATF6-associated ACHM is a structurally distinct form of congenital ACHM. Methods Seven genetically confirmed subjects from five nonconsanguineous families were recruited. Foveal hypoplasia and the integrity of the ellipsoid zone (EZ) band (a.k.a., IS/OS) were graded from optical coherence tomography (OCT) images. Images of the photoreceptor mosaic were acquired using confocal and nonconfocal split-detection adaptive optics scanning light ophthalmoscopy (AOSLO). Parafoveal cone and rod density values were calculated and compared to published normative data as well as data from two subjects harboring CNGA3 or CNGB3 mutations who were recruited for comparative purposes. Additionally, nonconfocal dark-field AOSLO images of the retinal pigment epithelium were obtained, with quantitative analysis performed in one subject with ATF6-ACHM. Results Foveal hypoplasia was observed in all subjects with ATF6 mutations. Absence of the EZ band within the foveal region (grade 3) or appearance of a hyporeflective zone (grade 4) was seen in all subjects with ATF6 using OCT. There was no evidence of remnant foveal cone structure using confocal AOSLO, although sporadic cone-like structures were seen in nonconfocal split-detection AOSLO. There was a lack of cone structure in the parafovea, in direct contrast to previous reports. Conclusions Our data demonstrate a near absence of cone structure in subjects harboring ATF6 mutations. This implicates ATF6 as having a major role in cone development and suggests that at least a subset of subjects with ATF6-ACHM have markedly fewer cellular targets for cone-directed gene therapies than do subjects with CNGA3- or CNGB3-ACHM.
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Affiliation(s)
- Rebecca R Mastey
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Michalis Georgiou
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - Christopher S Langlo
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Angelos Kalitzeos
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - Emily J Patterson
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Thomas Kane
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - Navjit Singh
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - Ajoy Vincent
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, The University of Toronto, Toronto, Canada
| | - Anthony T Moore
- Department of Ophthalmology, University of California-San Francisco Medical School, San Francisco, California, United States
| | - Stephen H Tsang
- Jonas Children's Vision Care, Departments of Ophthalmology, Pathology and Cell Biology, Columbia Stem Cell Initiative, New York, New York, United States
| | - Jonathan H Lin
- Department of Ophthalmology, University of California-San Diego, La Jolla, California, United States.,Department of Pathology, University of California-San Diego, La Jolla, California, United States
| | - Marielle P Young
- Moran Eye Center, University of Utah, Salt Lake City, Utah, United States
| | | | - Elise Héon
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, The University of Toronto, Toronto, Canada
| | - Susanne Kohl
- Centre for Ophthalmology Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - Joseph Carroll
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, United States.,Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
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46
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Gill JS, Moosajee M, Dubis AM. Cellular imaging of inherited retinal diseases using adaptive optics. Eye (Lond) 2019; 33:1683-1698. [PMID: 31164730 PMCID: PMC7002587 DOI: 10.1038/s41433-019-0474-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 02/25/2019] [Accepted: 04/25/2019] [Indexed: 12/14/2022] Open
Abstract
Adaptive optics (AO) is an insightful tool that has been increasingly applied to existing imaging systems for viewing the retina at a cellular level. By correcting for individual optical aberrations, AO offers an improvement in transverse resolution from 10-15 μm to ~2 μm, enabling assessment of individual retinal cell types. One of the settings in which its utility has been recognised is that of the inherited retinal diseases (IRDs), the genetic and clinical heterogeneity of which warrants better cellular characterisation. In this review, we provide a summary of the basic principles of AO, its integration into multiple retinal imaging modalities and its clinical applications, focusing primarily on IRDs. Furthermore, we present a comprehensive summary of AO-based cellular findings in IRDs according to their associated disease-causing genes.
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Affiliation(s)
- Jasdeep S Gill
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL, UK
| | - Mariya Moosajee
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL, UK
- NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Trust and UCL Institute of Ophthalmology, 162 City Road, London, EC1V 9PD, UK
- Great Ormond Street Hospital for Children, Great Ormond Street, London, WC1N 3JH, UK
| | - Adam M Dubis
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL, UK.
- NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Trust and UCL Institute of Ophthalmology, 162 City Road, London, EC1V 9PD, UK.
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47
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Zhang P, Miller EB, Manna SK, Meleppat RK, Pugh EN, Zawadzki RJ. Temporal speckle-averaging of optical coherence tomography volumes for in-vivo cellular resolution neuronal and vascular retinal imaging. NEUROPHOTONICS 2019; 6:041105. [PMID: 31528657 PMCID: PMC6732665 DOI: 10.1117/1.nph.6.4.041105] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 07/31/2019] [Indexed: 05/08/2023]
Abstract
It has been recently demonstrated that structures corresponding to the cell bodies of highly transparent cells in the retinal ganglion cell layer could be visualized noninvasively in the living human eye by optical coherence tomography (OCT) via temporal averaging. Inspired by this development, we explored the application of volumetric temporal averaging in mice, which are important models for studying human retinal diseases and therapeutic interventions. A general framework of temporal speckle-averaging (TSA) of OCT and optical coherence tomography angiography (OCTA) is presented and applied to mouse retinal volumetric data. Based on the image analysis, the eyes of mice under anesthesia exhibit only minor motions, corresponding to lateral displacements of a few micrometers and rotations of a fraction of 1 deg. Moreover, due to reduced eye movements under anesthesia, there is a negligible amount of motion artifacts within the volumes that need to be corrected to achieve volume coregistration. In addition, the relatively good optical quality of the mouse ocular media allows for cellular-resolution imaging without adaptive optics (AO), greatly simplifying the experimental system, making the proposed framework feasible for large studies. The TSA OCT and TSA OCTA results provide rich information about new structures previously not visualized in living mice with non-AO-OCT. The mechanism of TSA relies on improving signal-to-noise ratio as well as efficient suppression of speckle contrast due to temporal decorrelation of the speckle patterns, enabling full utilization of the high volumetric resolution offered by OCT and OCTA.
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Affiliation(s)
- Pengfei Zhang
- University of California Davis, Department of Cell Biology and Human Anatomy, UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Davis, California, United States
| | - Eric B. Miller
- University of California Davis, Center for Neuroscience, Davis, California, United States
| | - Suman K. Manna
- University of California Davis, Department of Cell Biology and Human Anatomy, UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Davis, California, United States
| | - Ratheesh K. Meleppat
- University of California Davis, Department of Cell Biology and Human Anatomy, UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Davis, California, United States
| | - Edward N. Pugh
- University of California Davis, Department of Cell Biology and Human Anatomy, UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Davis, California, United States
- University of California Davis, Department of Ophthalmology and Vision Science, Vision Science and Advanced Retinal Imaging Laboratory, Sacramento, California, United States
| | - Robert J. Zawadzki
- University of California Davis, Department of Cell Biology and Human Anatomy, UC Davis Eye-Pod Small Animal Ocular Imaging Laboratory, Davis, California, United States
- University of California Davis, Department of Ophthalmology and Vision Science, Vision Science and Advanced Retinal Imaging Laboratory, Sacramento, California, United States
- University of California Davis, UC Davis Eye Center, Department of Ophthalmology and Vision Science, Sacramento, California, United States
- Address all correspondence to Robert J. Zawadzki, E-mail:
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48
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Liu Z, Kurokawa K, Hammer DX, Miller DT. In vivo measurement of organelle motility in human retinal pigment epithelial cells. BIOMEDICAL OPTICS EXPRESS 2019; 10:4142-4158. [PMID: 31453000 PMCID: PMC6701538 DOI: 10.1364/boe.10.004142] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 06/24/2019] [Accepted: 06/24/2019] [Indexed: 05/18/2023]
Abstract
Retinal pigment epithelial (RPE) cells are well known to play a central role in the progression of numerous retinal diseases. Changes in the structure and function of these cells thus may serve as sensitive biomarkers of disease onset. While in vivo studies have focused on structural changes, functional ones may better capture cell health owing to their more direct connection to cell physiology. In this study, we developed a method based on adaptive optics optical coherence tomography (AO-OCT) and speckle field dynamics for characterizing organelle motility in individual RPE cells. We quantified the dynamics in terms of an exponential decay time constant, the time required for the speckle field to decorrelate. Using seven normal subjects, we found the RPE speckle field to decorrelate in about 5 s. This result has two fundamental implications for future clinical use. First, it establishes a path for generating a normative baseline to which motility of diseased RPE cells can be compared. Second, it predicts an AO-OCT image acquisition time that is 36 times faster than used in our earlier report for individuating RPE cells, thus a major improvement in clinical efficacy.
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Affiliation(s)
- Zhuolin Liu
- Center for Devices and Radiological Health (CDRH), U.S. Food and Drug Administration, 10903 New Hampshire Ave, Silver Spring, MD, 20993, USA
| | - Kazuhiro Kurokawa
- School of Optometry, Indiana University, 800 East Atwater Avenue, Bloomington, IN 47405, USA
| | - Daniel X. Hammer
- Center for Devices and Radiological Health (CDRH), U.S. Food and Drug Administration, 10903 New Hampshire Ave, Silver Spring, MD, 20993, USA
| | - Donald T. Miller
- School of Optometry, Indiana University, 800 East Atwater Avenue, Bloomington, IN 47405, USA
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49
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Zhang T, Kho AM, Srinivasan VJ. Improving visible light OCT of the human retina with rapid spectral shaping and axial tracking. BIOMEDICAL OPTICS EXPRESS 2019; 10:2918-2931. [PMID: 31259062 PMCID: PMC6583340 DOI: 10.1364/boe.10.002918] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/30/2019] [Accepted: 04/30/2019] [Indexed: 05/23/2023]
Abstract
Visible light optical coherence tomography (OCT) theoretically provides finer axial resolution than near-infrared OCT for a given wavelength bandwidth. To realize this potential in the human retina in vivo, the unique technical challenges of visible light OCT must be addressed. We introduce three advances to further the performance of visible light OCT in the human retina. First, we incorporate a grating light valve spatial light modulator (GLV-SLM) spectral shaping stage to modify the source spectrum. This enables comfortable subject alignment with a red light spectrum, and image acquisition with a broad "white light" spectrum, shaped to minimize sidelobes. Second, we develop a novel, Fourier transform-free, software axial motion tracking algorithm with fast, magnetically actuated stage to maintain near-optimal axial resolution and sensitivity in the presence of eye motion. Third, we implement spatially dependent numerical dispersion compensation for the first time in the human eye in vivo. In vivo human retinal OCT images clearly show that the inner plexiform layer consists of 3 hyper-reflective bands and 2 hypo-reflective bands, corresponding with the standard anatomical division of the IPL. Wavelength-dependent images of the outer retina suggest that, beyond merely improving the axial resolution, shorter wavelength visible light may also provide unique advantages for visualizing Bruch's membrane.
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Affiliation(s)
- Tingwei Zhang
- Biomedical Engineering Department, University of California Davis, Davis, California, 95616, USA
| | - Aaron M. Kho
- Biomedical Engineering Department, University of California Davis, Davis, California, 95616, USA
| | - Vivek J. Srinivasan
- Biomedical Engineering Department, University of California Davis, Davis, California, 95616, USA
- Department of Ophthalmology and Vision Science, University of California Davis School of Medicine, Sacramento, California, 95817, USA
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50
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Granger CE, Yang Q, Song H, Saito K, Nozato K, Latchney LR, Leonard BT, Chung MM, Williams DR, Rossi EA. Human Retinal Pigment Epithelium: In Vivo Cell Morphometry, Multispectral Autofluorescence, and Relationship to Cone Mosaic. Invest Ophthalmol Vis Sci 2019; 59:5705-5716. [PMID: 30513531 PMCID: PMC6280915 DOI: 10.1167/iovs.18-24677] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Purpose To characterize in vivo morphometry and multispectral autofluorescence of the retinal pigment epithelial (RPE) cell mosaic and its relationship to cone cell topography across the macula. Methods RPE cell morphometrics were computed in regularly spaced regions of interest (ROIs) from contiguous short-wavelength autofluorescence (SWAF) and photoreceptor reflectance images collected across the macula in one eye of 10 normal participants (23–65 years) by using adaptive optics scanning light ophthalmoscopy (AOSLO). Infrared autofluorescence (IRAF) images of the RPE were collected with AOSLO in seven normal participants (22–65 years), with participant overlap, and compared to SWAF quantitatively and qualitatively. Results RPE cell statistics could be analyzed in 84% of SWAF ROIs. RPE cell density consistently decreased with eccentricity from the fovea (participant mean ± SD: 6026 ± 1590 cells/mm2 at fovea; 4552 ± 1370 cells/mm2 and 3757 ± 1290 cells/mm2 at 3.5 mm temporally and nasally, respectively). Mean cone-to-RPE cell ratio decreased rapidly from 16.6 at the foveal center to <5 by 1 mm. IRAF revealed cells in six of seven participants, in agreement with SWAF RPE cell size and location. Differences in cell fluorescent structure, contrast, and visibility beneath vasculature were observed between modalities. Conclusions Improvements in AOSLO autofluorescence imaging permit efficient visualization of RPE cells with safe light exposures, allowing individual characterization of RPE cell morphometry that is variable between participants. The normative dataset and analysis of RPE cell IRAF and SWAF herein are essential for understanding microscopic characteristics of cell fluorescence and may assist in interpreting disease progression in RPE cells.
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Affiliation(s)
- Charles E Granger
- Center for Visual Science, University of Rochester, Rochester, New York, United States.,The Institute of Optics, University of Rochester, Rochester, New York, United States
| | - Qiang Yang
- Center for Visual Science, University of Rochester, Rochester, New York, United States
| | - Hongxin Song
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Key Laboratory of Ophthalmology and Visual Sciences, National Engineering Research Center for Ophthalmic Equipment, Beijing, China
| | - Kenichi Saito
- Canon U.S.A., Inc., Melville, New York, United States
| | - Koji Nozato
- Canon U.S.A., Inc., Melville, New York, United States
| | - Lisa R Latchney
- Flaum Eye Institute, University of Rochester Medical Center, Rochester, New York, United States
| | - Bianca T Leonard
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Mina M Chung
- Center for Visual Science, University of Rochester, Rochester, New York, United States.,Flaum Eye Institute, University of Rochester Medical Center, Rochester, New York, United States
| | - David R Williams
- Center for Visual Science, University of Rochester, Rochester, New York, United States.,The Institute of Optics, University of Rochester, Rochester, New York, United States
| | - Ethan A Rossi
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States.,Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
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