1
|
Pattni K, Wood A, Cassels N, Margrain T. Visual pigment concentration and photoreceptor outer segment length in the human retina. Ophthalmic Physiol Opt 2024; 44:917-924. [PMID: 38572814 DOI: 10.1111/opo.13307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 03/14/2024] [Accepted: 03/15/2024] [Indexed: 04/05/2024]
Abstract
PURPOSE The Beer-Lambert law suggests that visual pigment optical density (OD) should be linearly related to the length of photoreceptor outer segments (POSs). Mammalian studies indicate that visual pigment concentration increases with POS length, but the nature of this relationship may vary due to factors such as visual pigment packing density or retinal eccentricity, and may not necessarily be linearly related. The purpose of this study was to establish the relationship between OD and POS length in humans. METHODS Spectral domain optical coherence tomography (OCT) was used to image POS, and imaging retinal densitometry (IRD) was used to measure OD at corresponding locations in 19 healthy participants (age range 25-82 years). POS length and OD measurements were extracted from OCT and IRD images at 23 discrete locations spanning the central 9° of the retina. The averaged data from all participants were fitted with models based on the Beer-Lambert law to establish the relationship between OD and POS length. RESULTS Visual pigment OD increased monotonically with POS length, but the relationship was non-linear, and a straight-line fit, based on a simple interpretation of the Beer-Lambert law, provided a poor description. A model allowing for different rod and cone visual pigment concentrations provided a superior fit. Specifically, the data were well described by a model where the molar concentration of visual pigment in cones and rods were 3.8 × 10-3 mol/L and 1.8 × 10-3mol/L, respectively. CONCLUSIONS In accordance with the Beer-Lambert law, the results indicate that OD increases monotonically with POS length in humans, but the precise relationship is dependent on photoreceptor type. These results suggest that visual pigment concentration in rods is only about 48% of that found in cones. This may be due to the ubiquitous nature of artificial light that works to reduce the concentration of rhodopsin in rod photoreceptors.
Collapse
Affiliation(s)
- Krishna Pattni
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| | - Ashley Wood
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| | - Nicola Cassels
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| | - Tom Margrain
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| |
Collapse
|
2
|
Tan B, Li H, Zhuo Y, Han L, Mupparapu R, Nanni D, Barathi VA, Palanker D, Schmetterer L, Ling T. Light-evoked deformations in rod photoreceptors, pigment epithelium and subretinal space revealed by prolonged and multilayered optoretinography. Nat Commun 2024; 15:5156. [PMID: 38898002 DOI: 10.1038/s41467-024-49014-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 05/21/2024] [Indexed: 06/21/2024] Open
Abstract
Phototransduction involves changes in concentration of ions and other solutes within photoreceptors and in subretinal space, which affect osmotic pressure and the associated water flow. Corresponding expansion and contraction of cellular layers can be imaged using optoretinography (ORG), based on phase-resolved optical coherence tomography (OCT). Until now, ORG could reliably detect only photoisomerization and phototransduction in photoreceptors, primarily in cones under bright stimuli. Here, by employing a phase-restoring subpixel motion correction algorithm, which enables imaging of the nanometer-scale tissue dynamics during minute-long recordings, and unsupervised learning of spatiotemporal patterns, we discover optical signatures of the other retinal structures' response to visual stimuli. These include inner and outer segments of rod photoreceptors, retinal pigment epithelium, and subretinal space in general. The high sensitivity of our technique enables detection of the retinal responses to dim stimuli: down to 0.01% bleach level, corresponding to natural levels of scotopic illumination. We also demonstrate that with a single flash, the optoretinogram can map retinal responses across a 12° field of view, potentially replacing multifocal electroretinography. This technique expands the diagnostic capabilities and practical applicability of optoretinography, providing an alternative to electroretinography, while combining structural and functional retinal imaging in the same OCT machine.
Collapse
Affiliation(s)
- Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE) Program, Singapore, Singapore
| | - Huakun Li
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore
| | - Yueming Zhuo
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA, 94305, USA
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Le Han
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE) Program, Singapore, Singapore
| | - Rajeshkumar Mupparapu
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE) Program, Singapore, Singapore
| | - Davide Nanni
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore
| | - Veluchamy Amutha Barathi
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore, Singapore
| | - Daniel Palanker
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA, 94305, USA.
- Department of Ophthalmology, Stanford University, Stanford, CA, 94305, USA.
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.
- SERI-NTU Advanced Ocular Engineering (STANCE) Program, Singapore, Singapore.
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore.
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.
- Ophthalmology and Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore, Singapore.
- Department of Ophthalmology, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland.
| | - Tong Ling
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.
- SERI-NTU Advanced Ocular Engineering (STANCE) Program, Singapore, Singapore.
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore.
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, Singapore.
| |
Collapse
|
3
|
Luo X, Deng W, Sheng F, Ren X, Zhao Z, Zhao C, Liu Y, Shi J, Liu Z, Zhang X, Jie J. Bionic Scotopic Adaptation Transistors for Nighttime Low Illumination Imaging. ACS NANO 2024; 18:13726-13737. [PMID: 38742941 DOI: 10.1021/acsnano.4c01663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Human vision excels in perceiving nighttime low illumination due to biological feedforward adaptation. Replicating this ability in biomimetic vision using solid-state devices has been highly sought after. However, emulating scotopic adaptation, entailing a confluence of efficient photoexcitation and dynamic carrier modulation, presents formidable challenges. Here, we demonstrate a low-power and bionic scotopic adaptation transistor by coupling a light-absorption layer and an electron-trapping layer at the bottom of the semiconducting channel, enabling simultaneous achievement of efficient generation of free photocarriers and adaptive carrier accumulation within a single device. This innovation empowers our transistor to exhibit sensitivity-potentiated characteristics after adaptation, detecting scotopic-level illumination (0.001 lx) with exceptional photosensitivity up to 103 at low voltages below 2 V. Moreover, we have successfully replicated diverse scotopic vision functions, encompassing time-dependent visual threshold enhancement, light intensity-dependent adaptation index, imaging contrast enhancement for nighttime low illumination imaging, opening an opportunity for artificial night vision.
Collapse
Affiliation(s)
- Xiangkai Luo
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, China
| | - Wei Deng
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, China
| | - Fangming Sheng
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, China
| | - Xiaobin Ren
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, China
| | - Zishen Zhao
- School of Advanced Technology, Xi'an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
| | - Chun Zhao
- School of Advanced Technology, Xi'an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
| | - Yang Liu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, China
| | - Jialin Shi
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, China
| | - Zeke Liu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, China
| | - Xiujuan Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, China
| | - Jiansheng Jie
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, China
| |
Collapse
|
4
|
Xu P, Cooper RF, Jiang YY, Morgan JIW. Parafoveal cone function in choroideremia assessed with adaptive optics optoretinography. Sci Rep 2024; 14:8339. [PMID: 38594294 PMCID: PMC11004114 DOI: 10.1038/s41598-024-58059-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 03/25/2024] [Indexed: 04/11/2024] Open
Abstract
Choroideremia (CHM) is an X-linked retinal degeneration leading to loss of the photoreceptors, retinal pigment epithelium (RPE), and choroid. Adaptive optics optoretinography is an emerging technique for noninvasive, objective assessment of photoreceptor function. Here, we investigate parafoveal cone function in CHM using adaptive optics optoretinography and compare with cone structure and clinical assessments of vision. Parafoveal cone mosaics of 10 CHM and four normal-sighted participants were imaged with an adaptive optics scanning light ophthalmoscope. While acquiring video sequences, a 2 s 550Δ10 nm, 450 nW/deg2 stimulus was presented. Videos were registered and the intensity of each cone in each frame was extracted, normalized, standardized, and aggregated to generate the population optoretinogram (ORG) over time. A gamma-pdf was fit to the ORG and the peak was extracted as ORG amplitude. CHM ORG amplitudes were compared to normal and were correlated with bound cone density, ellipsoid zone to RPE/Bruch's membrane (EZ-to-RPE/BrM) distance, and foveal sensitivity using Pearson correlation analysis. ORG amplitude was significantly reduced in CHM compared to normal (0.22 ± 0.15 vs. 1.34 ± 0.31). In addition, CHM ORG amplitude was positively correlated with cone density, EZ-to-RPE/BrM distance, and foveal sensitivity. Our results demonstrate promise for using ORG as a biomarker of photoreceptor function.
Collapse
Affiliation(s)
- Peiluo Xu
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Robert F Cooper
- Department of Ophthalmology, Joint Department of Biomedical Engineering, Medical College of Wisconsin, Marquette University and Medical College of Wisconsin, Milwaukee, WI, 53233, USA
| | - Yu You Jiang
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Jessica I W Morgan
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania, Philadelphia, PA, 19104, USA.
| |
Collapse
|
5
|
Boff JM, Shrestha AP, Madireddy S, Viswaprakash N, Della Santina L, Vaithianathan T. The Interplay between Neurotransmitters and Calcium Dynamics in Retinal Synapses during Development, Health, and Disease. Int J Mol Sci 2024; 25:2226. [PMID: 38396913 PMCID: PMC10889697 DOI: 10.3390/ijms25042226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/25/2024] Open
Abstract
The intricate functionality of the vertebrate retina relies on the interplay between neurotransmitter activity and calcium (Ca2+) dynamics, offering important insights into developmental processes, physiological functioning, and disease progression. Neurotransmitters orchestrate cellular processes to shape the behavior of the retina under diverse circumstances. Despite research to elucidate the roles of individual neurotransmitters in the visual system, there remains a gap in our understanding of the holistic integration of their interplay with Ca2+ dynamics in the broader context of neuronal development, health, and disease. To address this gap, the present review explores the mechanisms used by the neurotransmitters glutamate, gamma-aminobutyric acid (GABA), glycine, dopamine, and acetylcholine (ACh) and their interplay with Ca2+ dynamics. This conceptual outline is intended to inform and guide future research, underpinning novel therapeutic avenues for retinal-associated disorders.
Collapse
Affiliation(s)
- Johane M Boff
- Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Abhishek P Shrestha
- Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Saivikram Madireddy
- College of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Nilmini Viswaprakash
- Department of Medical Education, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | | | - Thirumalini Vaithianathan
- Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Department of Ophthalmology, Hamilton Eye Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| |
Collapse
|
6
|
Kurokawa K, Nemeth M. Multifunctional adaptive optics optical coherence tomography allows cellular scale reflectometry, polarimetry, and angiography in the living human eye. BIOMEDICAL OPTICS EXPRESS 2024; 15:1331-1354. [PMID: 38404344 PMCID: PMC10890865 DOI: 10.1364/boe.505395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 01/15/2024] [Accepted: 01/16/2024] [Indexed: 02/27/2024]
Abstract
Clinicians are unable to detect glaucoma until substantial loss or dysfunction of retinal ganglion cells occurs. To this end, novel measures are needed. We have developed an optical imaging solution based on adaptive optics optical coherence tomography (AO-OCT) to discern key clinical features of glaucoma and other neurodegenerative diseases at the cellular scale in the living eye. Here, we test the feasibility of measuring AO-OCT-based reflectance, retardance, optic axis orientation, and angiogram at specifically targeted locations in the living human retina and optic nerve head. Multifunctional imaging, combined with focus stacking and global image registration algorithms, allows us to visualize cellular details of retinal nerve fiber bundles, ganglion cell layer somas, glial septa, superior vascular complex capillaries, and connective tissues. These are key histologic features of neurodegenerative diseases, including glaucoma, that are now measurable in vivo with excellent repeatability and reproducibility. Incorporating this noninvasive cellular-scale imaging with objective measurements will significantly enhance existing clinical assessments, which is pivotal in facilitating the early detection of eye disease and understanding the mechanisms of neurodegeneration.
Collapse
Affiliation(s)
- Kazuhiro Kurokawa
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Research Institute, Legacy Health, Portland, OR 97232, USA
| | - Morgan Nemeth
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Research Institute, Legacy Health, Portland, OR 97232, USA
| |
Collapse
|
7
|
Britten-Jones AC, Thai L, Flanagan JPM, Bedggood PA, Edwards TL, Metha AB, Ayton LN. Adaptive optics imaging in inherited retinal diseases: A scoping review of the clinical literature. Surv Ophthalmol 2024; 69:51-66. [PMID: 37778667 DOI: 10.1016/j.survophthal.2023.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 09/22/2023] [Accepted: 09/25/2023] [Indexed: 10/03/2023]
Abstract
Adaptive optics (AO) imaging enables direct, objective assessments of retinal cells. Applications of AO show great promise in advancing our understanding of the etiology of inherited retinal disease (IRDs) and discovering new imaging biomarkers. This scoping review systematically identifies and summarizes clinical studies evaluating AO imaging in IRDs. Ovid MEDLINE and EMBASE were searched on February 6, 2023. Studies describing AO imaging in monogenic IRDs were included. Study screening and data extraction were performed by 2 reviewers independently. This review presents (1) a broad overview of the dominant areas of research; (2) a summary of IRD characteristics revealed by AO imaging; and (3) a discussion of methodological considerations relating to AO imaging in IRDs. From 140 studies with AO outcomes, including 2 following subretinal gene therapy treatments, 75% included fewer than 10 participants with AO imaging data. Of 100 studies that included participants' genetic diagnoses, the most common IRD genes with AO outcomes are CNGA3, CNGB3, CHM, USH2A, and ABCA4. Confocal reflectance AO scanning laser ophthalmoscopy was the most reported imaging modality, followed by flood-illuminated AO and split-detector AO. The most common outcome was cone density, reported quantitatively in 56% of studies. Future research areas include guidelines to reduce variability in the reporting of AO methodology and a focus on functional AO techniques to guide the development of therapeutic interventions.
Collapse
Affiliation(s)
- Alexis Ceecee Britten-Jones
- Department of Optometry and Vision Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia; Department of Surgery (Ophthalmology), Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia.
| | - Lawrence Thai
- Department of Surgery (Ophthalmology), Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
| | - Jeremy P M Flanagan
- Department of Surgery (Ophthalmology), Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
| | - Phillip A Bedggood
- Department of Optometry and Vision Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Thomas L Edwards
- Department of Surgery (Ophthalmology), Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
| | - Andrew B Metha
- Department of Optometry and Vision Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Lauren N Ayton
- Department of Optometry and Vision Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia; Department of Surgery (Ophthalmology), Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
| |
Collapse
|
8
|
Chen S, Ni S, Jiménez-Villar A, Jian Y, Jia Y, Huang D. Optical coherence tomography split-spectrum amplitude-decorrelation optoretinography. OPTICS LETTERS 2023; 48:3921-3924. [PMID: 37527083 DOI: 10.1364/ol.492178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 06/29/2023] [Indexed: 08/03/2023]
Abstract
This pilot study reports the development of optical coherence tomography (OCT) split-spectrum amplitude-decorrelation optoretinography (SSADOR) that measures spatially resolved photoreceptor response to light stimuli. Using spectrally multiplexed narrowband OCT, SSADOR improves sensitivity to microscopic changes without the need for cellular resolution or optical phase detection. Therefore, a large field of view (up to 3 × 1 mm2 demonstrated) using conventional OCT instrument design can be achieved, paving the way for clinical translation. SSADOR promises a fast, objective, and quantifiable functional biomarker for photoreceptor damage in the macula.
Collapse
|
9
|
Fernández-Suárez E, González-del Pozo M, García-Núñez A, Méndez-Vidal C, Martín-Sánchez M, Mejías-Carrasco JM, Ramos-Jiménez M, Morillo-Sánchez MJ, Rodríguez-de la Rúa E, Borrego S, Antiñolo G. Expanding the phenotype of THRB: a range of macular dystrophies as the major clinical manifestations in patients with a dominant splicing variant. Front Cell Dev Biol 2023; 11:1197744. [PMID: 37547476 PMCID: PMC10401274 DOI: 10.3389/fcell.2023.1197744] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 06/27/2023] [Indexed: 08/08/2023] Open
Abstract
Inherited retinal dystrophies (IRDs) are a clinically and genetically heterogeneous group of disorders that often severely impair vision. Some patients manifest poor central vision as the first symptom due to cone-dysfunction, which is consistent with cone dystrophy (COD), Stargardt disease (STGD), or macular dystrophy (MD) among others. Here, we aimed to identify the genetic cause of autosomal dominant COD in one family. WGS was performed in 3 affected and 1 unaffected individual using the TruSeq Nano DNA library kit and the NovaSeq 6,000 platform (Illumina). Data analysis identified a novel spliceogenic variant (c.283 + 1G>A) in the thyroid hormone receptor beta gene (THRB) as the candidate disease-associated variant. Further genetic analysis revealed the presence of the same heterozygous variant segregating in two additional unrelated dominant pedigrees including 9 affected individuals with a diagnosis of COD (1), STGD (4), MD (3) and unclear phenotype (1). THRB has been previously reported as a causal gene for autosomal dominant and recessive thyroid hormone resistance syndrome beta (RTHβ); however, none of the IRD patients exhibited RTHβ. Genotype-phenotype correlations showed that RTHβ can be caused by both truncating and missense variants, which are mainly located at the 3' (C-terminal/ligand-binding) region, which is common to both THRB isoforms (TRβ1 and TRβ2). In contrast, the c.283 + 1G>A variant is predicted to disrupt a splice site in the 5'-region of the gene that encodes the N-terminal domain of the TRβ1 isoform protein, leaving the TRβ2 isoform intact, which would explain the phenotypic variability observed between RTHβ and IRD patients. Interestingly, although monochromacy or cone response alterations have already been described in a few RTHβ patients, herein we report the first genetic association between a pathogenic variant in THRB and non-syndromic IRDs. We thereby expand the phenotype of THRB pathogenic variants including COD, STGD, or MD as the main clinical manifestation, which also reflects the extraordinary complexity of retinal functions mediated by the different THRB isoforms.
Collapse
Affiliation(s)
- Elena Fernández-Suárez
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain
- Center for Biomedical Network Research on Rare Diseases (CIBERER), Seville, Spain
| | - María González-del Pozo
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain
- Center for Biomedical Network Research on Rare Diseases (CIBERER), Seville, Spain
| | - Alejandro García-Núñez
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain
| | - Cristina Méndez-Vidal
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain
- Center for Biomedical Network Research on Rare Diseases (CIBERER), Seville, Spain
| | - Marta Martín-Sánchez
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain
- Center for Biomedical Network Research on Rare Diseases (CIBERER), Seville, Spain
| | - José Manuel Mejías-Carrasco
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain
| | - Manuel Ramos-Jiménez
- Department of Clinical Neurophysiology, University Hospital Virgen Macarena, Seville, Spain
| | | | - Enrique Rodríguez-de la Rúa
- Department of Ophthalmology, University Hospital Virgen Macarena, Seville, Spain
- RETICS Patología Ocular, OFTARED, Instituto de Salud Carlos III, Madrid, Spain
| | - Salud Borrego
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain
- Center for Biomedical Network Research on Rare Diseases (CIBERER), Seville, Spain
| | - Guillermo Antiñolo
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain
- Center for Biomedical Network Research on Rare Diseases (CIBERER), Seville, Spain
| |
Collapse
|
10
|
Hisham M, Salih AE, Butt H. 3D Printing of Multimaterial Contact Lenses. ACS Biomater Sci Eng 2023; 9:4381-4391. [PMID: 37364228 PMCID: PMC10336843 DOI: 10.1021/acsbiomaterials.3c00175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 06/12/2023] [Indexed: 06/28/2023]
Abstract
3D printing of multimaterial objects is an emerging field with promising applications. The layer-by-layer material addition technique used in 3D printing enables incorporation of distinct functionalized materials into the specialized devices. However, very few studies have been performed on the usage of multimaterial 3D printing for printable photonic and wearable devices. Here, we employ vat photopolymerization-based 3D printing to produce multimaterial contact lenses, offering enhanced multiband optical filtration, which can be valuable for tackling ocular conditions such as color blindness. A combination of hydroxyethyl methacrylate (HEMA) and polyethylene glycol diacrylate (PEGDA) was used as the base hydrogel for 3D printing. Atto565 and Atto488 dyes were added to the hydrogel for wavelength filtering, each dye suitable for a different type of color blindness. Multimaterial disks and contact lenses, with separate sections containing distinct dyes, were 3D-printed, and their optical properties were studied. The characteristics of multimaterial printing were analyzed, focusing on the formation of a uniform multimaterial interface. In addition, a novel technique was developed for printing multiple dyed materials in complex lateral geometrical patterns, by employing suitable variations in CAD models and the UV curing time. It was observed that the multimaterial printing process does not negatively affect the optical properties of the contact lenses. The printed multimaterial contact lenses offered a combined multi-band color blindness correction due to the two dyes used. The resulting optical spectrum was a close match to the commercially available color blindness correction glasses.
Collapse
Affiliation(s)
- Muhammed Hisham
- Department of Mechanical
Engineering, Khalifa University, Abu Dhabi 127788, United Arab Emirates
| | - Ahmed E. Salih
- Department of Mechanical
Engineering, Khalifa University, Abu Dhabi 127788, United Arab Emirates
| | - Haider Butt
- Department of Mechanical
Engineering, Khalifa University, Abu Dhabi 127788, United Arab Emirates
| |
Collapse
|
11
|
Duncan JL, Carroll J. Adaptive Optics Imaging of Inherited Retinal Disease. Cold Spring Harb Perspect Med 2023; 13:a041285. [PMID: 36220331 PMCID: PMC10317068 DOI: 10.1101/cshperspect.a041285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The human retina is amenable to direct, noninvasive visualization using a wide array of imaging modalities. In the ∼140 years since the publication of the first image of the living human retina, there has been a continued evolution of retinal imaging technology. Advances in image acquisition and processing speed now allow real-time visualization of retinal structure, which has revolutionized the diagnosis and management of eye disease. Enormous advances have come in image resolution, with adaptive optics (AO)-based systems capable of imaging the retina with single-cell resolution. In addition, newer functional imaging techniques provide the ability to assess function with exquisite spatial and temporal resolution. These imaging advances have had an especially profound impact on the field of inherited retinal disease research. Here we will review some of the advances and applications of AO retinal imaging in patients with inherited retinal disease.
Collapse
Affiliation(s)
- Jacque L Duncan
- Department of Ophthalmology, University of California, San Francisco, California 94143-4081, USA
| | - Joseph Carroll
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin Eye Institute, Milwaukee, Wisconsin 53226, USA
| |
Collapse
|
12
|
Wang Y, Wong J, Duncan JL, Roorda A, Tuten WS. Enhanced S-Cone Syndrome: Elevated Cone Counts Confer Supernormal Visual Acuity in the S-Cone Pathway. Invest Ophthalmol Vis Sci 2023; 64:17. [PMID: 37459066 PMCID: PMC10362924 DOI: 10.1167/iovs.64.10.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023] Open
Abstract
Purpose To measure photoreceptor packing density and S-cone spatial resolution as a function of retinal eccentricity in patients with enhanced S-cone syndrome (ESCS) and to discuss the possible mechanisms supporting their supernormal S-cone acuity. Methods We used an adaptive optics scanning laser ophthalmoscope (AOSLO) to characterize photoreceptor packing. A custom non-AO display channel was used to measure L/M- and S-cone-mediated visual acuity during AOSLO imaging. Acuity measurements were obtained using a four-alternative, forced-choice, tumbling E paradigm along the temporal meridian between the fovea and 4° eccentricity in five of six patients and in seven control subjects. L/M acuity was tested by presenting long-pass-filtered optotypes on a black background, excluding wavelengths to which S-cones are sensitive. S-cone isolation was achieved using a two-color, blue-on-yellow chromatic adaptation method that was validated on three control subjects. Results Inter-cone spacing measurements revealed a near-uniform cone density profile (ranging from 0.9-1.5 arcmin spacing) throughout the macula in ESCS. For comparison, normal cone density decreases by a factor of 14 from the fovea to 6°. Cone spacing of ESCS subjects was higher than normal in the fovea and subnormal beyond 2°. Compared to the control subjects (n = 7), S-cone-mediated acuities in patients with ESCS were normal near the fovea and became increasingly supernormal with retinal eccentricity. Beyond 2°, S-cone acuities were superior to L/M-cone-mediated acuity in the ESCS cohort, a reversal of the trend observed in normal retinas. Conclusions Higher than normal parafoveal cone densities (presumably dominated by S-cones) confer better than normal S-cone-mediated acuity in ESCS subjects.
Collapse
Affiliation(s)
- Yiyi Wang
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, California, United States
| | - Jessica Wong
- Department of Ophthalmology, University of California, San Francisco, California, United States
| | - Jacque L Duncan
- Department of Ophthalmology, University of California, San Francisco, California, United States
| | - Austin Roorda
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, California, United States
| | - William S Tuten
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, California, United States
| |
Collapse
|
13
|
Beygi A. Universality of Form: The Case of Retinal Cone Photoreceptor Mosaics. ENTROPY (BASEL, SWITZERLAND) 2023; 25:e25050766. [PMID: 37238521 DOI: 10.3390/e25050766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/28/2023] [Accepted: 05/05/2023] [Indexed: 05/28/2023]
Abstract
Cone photoreceptor cells are wavelength-sensitive neurons in the retinas of vertebrate eyes and are responsible for color vision. The spatial distribution of these nerve cells is commonly referred to as the cone photoreceptor mosaic. By applying the principle of maximum entropy, we demonstrate the universality of retinal cone mosaics in vertebrate eyes by examining various species, namely, rodent, dog, monkey, human, fish, and bird. We introduce a parameter called retinal temperature, which is conserved across the retinas of vertebrates. The virial equation of state for two-dimensional cellular networks, known as Lemaître's law, is also obtained as a special case of our formalism. We investigate the behavior of several artificially generated networks and the natural one of the retina concerning this universal, topological law.
Collapse
Affiliation(s)
- Alireza Beygi
- Department of Molecular Bioinformatics, Institute of Computer Science, Goethe University Frankfurt, 60325 Frankfurt am Main, Germany
| |
Collapse
|
14
|
Huang L, Li R, Ye L, Zhang S, Tian H, Du M, Qu C, Li S, Li J, Yang M, Wu B, Chen R, Huang G, Zhong L, Yang H, Yu M, Shi Y, Wang C, Zhang H, Chen W, Yang Z. Deep Sc-RNA sequencing decoding the molecular dynamic architecture of the human retina. SCIENCE CHINA. LIFE SCIENCES 2023; 66:496-515. [PMID: 36115892 DOI: 10.1007/s11427-021-2163-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 07/13/2022] [Indexed: 10/14/2022]
Abstract
The human retina serves as a light detector and signals transmission tissue. Advanced insights into retinal disease mechanisms and therapeutic strategies require a deep understanding of healthy retina molecular events. Here, we sequenced the mRNA of over 0.6 million single cells from human retinas across six regions at nine different ages. Sixty cell sub-types have been identified from the human mature retinas with unique markers. We revealed regional and age differences of gene expression profiles within the human retina. Cell-cell interaction analysis indicated a rich synaptic connection within the retinal cells. Gene expression regulon analysis revealed the specific expression of transcription factors and their regulated genes in human retina cell types. Some of the gene's expression, such as DKK3, are elevated in aged retinas. A further functional investigation suggested that over expression of DKK3 could impact mitochondrial stability. Overall, decoding the molecular dynamic architecture of the human retina improves our understanding of the vision system.
Collapse
Affiliation(s)
- Lulin Huang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
- Research Unit for Blindness Prevention of Chinese Academy of Medical Sciences (2019RU026), Sichuan Academy of Medical Sciences, Chengdu, 610075, China
| | - Runze Li
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Lin Ye
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Shanshan Zhang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Huaping Tian
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Mingyan Du
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Chao Qu
- Department of Ophthalmology, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Shujin Li
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Jie Li
- Department of Ophthalmology, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Mu Yang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Biao Wu
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, 325035, China
| | - Ran Chen
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, 325035, China
| | - Guo Huang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Ling Zhong
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Hongjie Yang
- Department of Organ Transplant Center, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Man Yu
- Department of Ophthalmology, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Yi Shi
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Changguan Wang
- Department of Ophthalmology, Peking University Third Hospital, Beijing, 100730, China
| | - Houbin Zhang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Wei Chen
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, 325035, China
| | - Zhenglin Yang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China.
- Research Unit for Blindness Prevention of Chinese Academy of Medical Sciences (2019RU026), Sichuan Academy of Medical Sciences, Chengdu, 610075, China.
| |
Collapse
|
15
|
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.
Collapse
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
| |
Collapse
|
16
|
Palczewska G, Wojtkowski M, Palczewski K. From mouse to human: Accessing the biochemistry of vision in vivo by two-photon excitation. Prog Retin Eye Res 2023; 93:101170. [PMID: 36787681 PMCID: PMC10463242 DOI: 10.1016/j.preteyeres.2023.101170] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 02/03/2023] [Accepted: 02/06/2023] [Indexed: 02/13/2023]
Abstract
The eye is an ideal organ for imaging by a multi-photon excitation approach, because ocular tissues such as the sclera, cornea, lens and neurosensory retina, are highly transparent to infrared (IR) light. The interface between the retina and the retinal pigment epithelium (RPE) is especially informative, because it reflects the health of the visual (retinoid) cycle and its changes in response to external stress, genetic manipulations, and drug treatments. Vitamin A-derived retinoids, like retinyl esters, are natural fluorophores that respond to multi-photon excitation with near IR light, bypassing the filter-like properties of the cornea, lens, and macular pigments. Also, during natural aging some retinoids form bisretinoids, like diretinoid-pyridiniumethanolamine (A2E), that are highly fluorescent. These bisretinoids appear to be elevated concurrently with aging. Vitamin A-derived retinoids and bisretinoidss are detected by two-photon ophthalmoscopy (2PO), using a new class of light sources with adjustable spatial, temporal, and spectral properties. Furthermore, the two-photon (2P) absorption of IR light by the visual pigments in rod and cone photoreceptors can initiate visual transduction by cis-trans isomerization of retinal, enabling parallel functional studies. Recently we overcame concerns about safety, data interpretation and complexity of the 2P-based instrumentation, the major roadblocks toward advancing this modality to the clinic. These imaging and retina-function assessment advancements have enabled us to conduct the first 2P studies with humans.
Collapse
Affiliation(s)
- Grazyna Palczewska
- Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, CA, USA; International Center for Translational Eye Research, Polish Academy of Sciences, Warsaw, Poland; Polgenix, Inc., Department of Medical Devices, Cleveland, OH, USA; Department of Physical Chemistry of Biological Systems, Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland.
| | - Maciej Wojtkowski
- International Center for Translational Eye Research, Polish Academy of Sciences, Warsaw, Poland; Department of Physical Chemistry of Biological Systems, Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland; Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Torun, Poland.
| | - Krzysztof Palczewski
- Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, CA, USA; Department of Physiology & Biophysics, School of Medicine, And Chemistry, Molecular Biology and Biochemistry, University of California, Irvine, CA, USA.
| |
Collapse
|
17
|
Ma G, Son T, Adejumo T, Yao X. Rotational Distortion and Compensation in Optical Coherence Tomography with Anisotropic Pixel Resolution. Bioengineering (Basel) 2023; 10:313. [PMID: 36978706 PMCID: PMC10045376 DOI: 10.3390/bioengineering10030313] [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: 12/16/2022] [Revised: 02/24/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023] Open
Abstract
Accurate image registration is essential for eye movement compensation in optical coherence tomography (OCT) and OCT angiography (OCTA). The spatial resolution of an OCT instrument is typically anisotropic, i.e., has different resolutions in the lateral and axial dimensions. When OCT images have anisotropic pixel resolution, residual distortion (RD) and false translation (FT) are always observed after image registration for rotational movement. In this study, RD and FT were quantitively analyzed over different degrees of rotational movement and various lateral and axial pixel resolution ratio (RL/RA) values. The RD and FT provide the evaluation criteria for image registration. The theoretical analysis confirmed that the RD and FT increase significantly with the rotation degree and RL/RA. An image resizing assisting registration (RAR) strategy was proposed for accurate image registration. The performance of direct registration (DR) and RAR for retinal OCT and OCTA images were quantitatively compared. Experimental results confirmed that unnormalized RL/RA causes RD and FT; RAR can effectively improve the performance of OCT and OCTA image registration and distortion compensation.
Collapse
Affiliation(s)
- Guangying Ma
- Department of Biomedical Engineering, University of Illinois Chicago, Chicago, IL 60607, USA
| | - Taeyoon Son
- Department of Biomedical Engineering, University of Illinois Chicago, Chicago, IL 60607, USA
| | - Tobiloba Adejumo
- Department of Biomedical Engineering, University of Illinois Chicago, Chicago, IL 60607, USA
| | - Xincheng Yao
- Department of Biomedical Engineering, University of Illinois Chicago, Chicago, IL 60607, USA
- Department of Ophthalmology and Visual Sciences, University of Illinois Chicago, Chicago, IL 60612, USA
| |
Collapse
|
18
|
Williams DR, Burns SA, Miller DT, Roorda A. Evolution of adaptive optics retinal imaging [Invited]. BIOMEDICAL OPTICS EXPRESS 2023; 14:1307-1338. [PMID: 36950228 PMCID: PMC10026580 DOI: 10.1364/boe.485371] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 02/02/2023] [Indexed: 05/02/2023]
Abstract
This review describes the progress that has been achieved since adaptive optics (AO) was incorporated into the ophthalmoscope a quarter of a century ago, transforming our ability to image the retina at a cellular spatial scale inside the living eye. The review starts with a comprehensive tabulation of AO papers in the field and then describes the technological advances that have occurred, notably through combining AO with other imaging modalities including confocal, fluorescence, phase contrast, and optical coherence tomography. These advances have made possible many scientific discoveries from the first maps of the topography of the trichromatic cone mosaic to exquisitely sensitive measures of optical and structural changes in photoreceptors in response to light. The future evolution of this technology is poised to offer an increasing array of tools to measure and monitor in vivo retinal structure and function with improved resolution and control.
Collapse
Affiliation(s)
- David R. Williams
- The Institute of Optics and the Center for
Visual Science, University of Rochester,
Rochester NY, USA
| | - Stephen A. Burns
- School of Optometry, Indiana
University at Bloomington, Bloomington IN, USA
| | - Donald T. Miller
- School of Optometry, Indiana
University at Bloomington, Bloomington IN, USA
| | - Austin Roorda
- Herbert Wertheim School of Optometry and
Vision Science, University of California at Berkeley, Berkeley CA, USA
| |
Collapse
|
19
|
Veysset D, Zhuo Y, Hattori J, Buckhory M, Palanker D. Interferometric thermometry of ocular tissues for retinal laser therapy. BIOMEDICAL OPTICS EXPRESS 2023; 14:37-53. [PMID: 36698667 PMCID: PMC9842005 DOI: 10.1364/boe.475705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/13/2022] [Accepted: 11/14/2022] [Indexed: 06/17/2023]
Abstract
Controlling the tissue temperature rise during retinal laser therapy is highly desirable for predictable and reproducible outcomes of the procedure, especially with non-damaging settings. In this work, we demonstrate a method for determining the optical absorption, the thermal conductivity, and the thermal expansion coefficients of RPE and choroid using phase-resolved optical coherence tomography (pOCT). These parameters are extracted from the measured changes in the optical path length (ΔOPL) using an axisymmetric thermo-mechanical model. This allows the calculation of the temperature rise during hyperthermia, which was further validated by imaging the temperature-sensitive fluorescence at the same location. We demonstrate that, with a temperature uncertainty of ±0.9°C and a peak heating of about 17°C following a laser pulse of 20 ms, this methodology is expected to be safe and sufficiently precise for calibration of the non-damaging retinal laser therapy. The method is directly translatable to in-vivo studies, where we expect a similar precision.
Collapse
Affiliation(s)
- David Veysset
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305, USA
- Department of Ophthalmology, Stanford University, Stanford, CA 94305, USA
| | - Yueming Zhuo
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305, USA
- Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Junya Hattori
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305, USA
- Department of Mechanical Engineering, The University of Tokyo, Tokyo, Japan
| | - Mohajeet Buckhory
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305, USA
- Department of Ophthalmology, Stanford University, Stanford, CA 94305, USA
| | - Daniel Palanker
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305, USA
- Department of Ophthalmology, Stanford University, Stanford, CA 94305, USA
| |
Collapse
|
20
|
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.
Collapse
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
| |
Collapse
|
21
|
Pandiyan VP, Schleufer S, Slezak E, Fong J, Upadhyay R, Roorda A, Ng R, Sabesan R. Characterizing cone spectral classification by optoretinography. BIOMEDICAL OPTICS EXPRESS 2022; 13:6574-6594. [PMID: 36589563 PMCID: PMC9774847 DOI: 10.1364/boe.473608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 10/26/2022] [Accepted: 10/27/2022] [Indexed: 05/02/2023]
Abstract
Light propagation in photoreceptor outer segments is affected by photopigment absorption and the phototransduction amplification cascade. Photopigment absorption has been studied using retinal densitometry, while recently, optoretinography (ORG) has provided an avenue to probe changes in outer segment optical path length due to phototransduction. With adaptive optics (AO), both densitometry and ORG have been used for cone spectral classification based on the differential bleaching signatures of the three cone types. Here, we characterize cone classification by ORG, implemented in an AO line-scan optical coherence tomography (OCT), and compare it against densitometry. The cone mosaics of five color normal subjects were classified using ORG showing high probability (∼0.99), low error (<0.22%), high test-retest reliability (∼97%), and short imaging durations (< 1 hour). Of these, the cone spectral assignments in two subjects were compared against AO-scanning laser opthalmoscope densitometry. High agreement (mean: 91%) was observed between the two modalities in these two subjects, with measurements conducted 6-7 years apart. Overall, ORG benefits from higher sensitivity and dynamic range to probe cone photopigments compared to densitometry, and thus provides greater fidelity for cone spectral classification.
Collapse
Affiliation(s)
- Vimal Prabhu Pandiyan
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA, USA
| | - Sierra Schleufer
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA, USA
- Graduate Program in Neuroscience, University of Washington, Seattle, WA, USA
| | - Emily Slezak
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA, USA
| | - James Fong
- Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA, USA
| | - Rishi Upadhyay
- Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA, USA
| | - Austin Roorda
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA, USA
| | - Ren Ng
- Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA, USA
| | - Ramkumar Sabesan
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA, USA
- Graduate Program in Neuroscience, University of Washington, Seattle, WA, USA
| |
Collapse
|
22
|
Berkowitz BA, Podolsky RH, Childers KL, Roberts R, Katz R, Waseem R, Robbings BM, Hass DT, Hurley JB, Sweet IR, Goodman C, Qian H, Alvisio B, Heaps S. Transducin-Deficient Rod Photoreceptors Evaluated With Optical Coherence Tomography and Oxygen Consumption Rate Energy Biomarkers. Invest Ophthalmol Vis Sci 2022; 63:22. [PMID: 36576748 PMCID: PMC9804021 DOI: 10.1167/iovs.63.13.22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Purpose To test the hypothesis that rod energy biomarkers in light and dark are similar in mice without functional rod transducin (Gnat1rd17). Methods Gnat1rd17 and wildtype (WT) mice were studied in canonically low energy demand (light) and high energy demand (dark) conditions. We measured rod inner segment ellipsoid zone (ISez) profile shape, external limiting membrane-retinal pigment epithelium (ELM-RPE) thickness, and magnitude of a hyporeflective band (HB) intensity dip located between photoreceptor tips and apical RPE; antioxidants were given in a subset of mice. Oxygen consumption rate (OCR) and visual performance indexes were also measured. Results The lower energy demand expected in light-adapted wildtype retinas was associated with an elongated ISez, thicker ELM-RPE, and higher HB magnitude, and lower OCR compared to high energy demand conditions in the dark. Gnat1rd17 mice showed a wildtype-like ISez profile shape at 20 minutes of light that became rounder at 60 minutes; at both times, ELM-RPE was smaller than wildtype values, and the HB magnitude was unmeasurable. OCR was higher than in the dark. Light-adapted Gnat1rd17 mice biomarkers were unaffected by anti-oxidants. Gnat1rd17 mice showed modest outer nuclear layer thinning and no reduction in visual performance indexes. Conclusions Light-stimulated changes in all biomarkers in WT mice are consistent with the established light-induced decrease in net energy demand. In contrast, biomarker changes in Gnat1rd17 mice raise the possibility that light increases net energy demand in the absence of rod phototransduction.
Collapse
Affiliation(s)
- Bruce A Berkowitz
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Robert H Podolsky
- Biostatistics and Study Methodology, Children's National Hospital, Silver Spring, Maryland, United States
| | - Karen Lins Childers
- Beaumont Research Institute, Beaumont Health, Royal Oak, Michigan, United States
| | - Robin Roberts
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Ryan Katz
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Rida Waseem
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Brian M Robbings
- Department of Biochemistry, Department of Ophthalmology, University of Washington, Seattle, Washington, United States.,Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, Washington, United States
| | - Daniel T Hass
- Department of Biochemistry, Department of Ophthalmology, University of Washington, Seattle, Washington, United States
| | - James B Hurley
- Department of Biochemistry, Department of Ophthalmology, University of Washington, Seattle, Washington, United States
| | - Ian R Sweet
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, Washington, United States
| | - Cole Goodman
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Haohua Qian
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Bruno Alvisio
- OSIO Bioinformatics Core, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Sam Heaps
- OSIO Bioinformatics Core, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| |
Collapse
|
23
|
Warner RL, Brainard DH, Morgan JIW. Repeatability and reciprocity of the cone optoretinogram. BIOMEDICAL OPTICS EXPRESS 2022; 13:6561-6573. [PMID: 36589578 PMCID: PMC9774868 DOI: 10.1364/boe.471990] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 11/08/2022] [Accepted: 11/08/2022] [Indexed: 05/02/2023]
Abstract
Optoretinography has enabled noninvasive visualization of physiological changes in cone photoreceptors exposed to light. Understanding the cone optoretinogram in healthy subjects is essential for establishing it as a biomarker for cone function in disease. Here, we measure the population cone intensity optoretinogram in healthy adults, for multiple irradiance/duration combinations of visible stimuli with equal energy. We study the within and between session repeatability and reciprocity of the ORG in five healthy subjects. We find the cone optoretinogram exhibits equivalent amplitudes for equal-energy stimuli. We also find good within-subject repeatability, which allows us to show differences across the five subjects.
Collapse
Affiliation(s)
- R. L. Warner
- Scheie Eye Institute, Department of
Ophthalmology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - D. H. Brainard
- Psychology Department, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - J. 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
| |
Collapse
|
24
|
Mozaffari S, Feroldi F, LaRocca F, Tiruveedhula P, Gregory PD, Park BH, Roorda A. Retinal imaging using adaptive optics optical coherence tomography with fast and accurate real-time tracking. BIOMEDICAL OPTICS EXPRESS 2022; 13:5909-5925. [PMID: 36733754 PMCID: PMC9872892 DOI: 10.1364/boe.467634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/11/2022] [Accepted: 10/04/2022] [Indexed: 05/02/2023]
Abstract
One of the main obstacles in high-resolution 3-D retinal imaging is eye motion, which causes blur and distortion artifacts that require extensive post-processing to be corrected. Here, an adaptive optics optical coherence tomography (AOOCT) system with real-time active eye motion correction is presented. Correction of ocular aberrations and of retinal motion is provided by an adaptive optics scanning laser ophthalmoscope (AOSLO) that is optically and electronically combined with the AOOCT system. We describe the system design and quantify its performance. The AOOCT system features an independent focus adjustment that allows focusing on different retinal layers while maintaining the AOSLO focus on the photoreceptor mosaic for high fidelity active motion correction. The use of a high-quality reference frame for eye tracking increases revisitation accuracy between successive imaging sessions, allowing to collect several volumes from the same area. This system enables spatially targeted retinal imaging as well as volume averaging over multiple imaging sessions with minimal correction of motion in post processing.
Collapse
Affiliation(s)
- Sanam Mozaffari
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Fabio Feroldi
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Francesco LaRocca
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Pavan Tiruveedhula
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Patrick D. Gregory
- Department of Bioengineering, University of California, Riverside, CA 92521, USA
| | - B. Hyle Park
- Department of Bioengineering, University of California, Riverside, CA 92521, USA
| | - Austin Roorda
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA 94720, USA
| |
Collapse
|
25
|
Jiang X, Liu T, Pandiyan VP, Slezak E, Sabesan R. Coarse-scale optoretinography (CoORG) with extended field-of-view for normative characterization. BIOMEDICAL OPTICS EXPRESS 2022; 13:5989-6002. [PMID: 36733759 PMCID: PMC9872880 DOI: 10.1364/boe.473475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/04/2022] [Accepted: 10/11/2022] [Indexed: 05/02/2023]
Abstract
Optoretinography (ORG) has the potential to be an effective biomarker for light-evoked retinal activity owing to its sensitive, objective, and precise localization of retinal function and dysfunction. Many ORG implementations have used adaptive optics (AO) to localize activity on a cellular scale. However, the use of AO restricts field-of-view (FOV) to the isoplanatic angle, necessitating the montaging of multiple regions-of-interest to cover an extended field. In addition, subjects with lens opacities, increased eye movements and decreased mobility pose challenges for effective AO operation. Here, we developed a coarse-scale ORG (CoORG) system without AO, which accommodates FOVs up to 5.5 deg. in a single acquisition. The system is based on a line-scan spectral domain OCT with volume rates of up to 32 Hz (16,000 B-frames per second). For acquiring ORGs, 5.5 deg. wide OCT volumes were recorded after dark adaptation and two different stimulus bleaches. The stimulus-evoked optical phase change was calculated from the reflections encasing the cone outer segments and its variation was assessed vs. eccentricity in 12 healthy subjects. The general behavior of ΔOPL vs. time mimicked published reports. High trial-to-trial repeatability was observed across subjects and with eccentricity. Comparison of ORG between CoORG and AO-OCT based ORG at 1.5°, 2.5°, and 3.5° eccentricity showed an excellent agreement in the same 2 subjects. The amplitude of the ORG response decreased with increasing eccentricity. The variation of ORG characteristics between subjects and versus eccentricity was well explained by the photon density of the stimulus on the retina and the outer segment length. Overall, the high repeatability and rapid acquisition over an extended field enabled the normative characterization of the cone ORG response in healthy eyes, and provides a promising avenue for translating ORG for widespread clinical application.
Collapse
Affiliation(s)
- Xiaoyun Jiang
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA 98109, USA
| | - Teng Liu
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA 98109, USA
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Vimal Prabhu Pandiyan
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA 98109, USA
| | - Emily Slezak
- 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
| |
Collapse
|
26
|
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.
Collapse
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
| |
Collapse
|
27
|
Patterson EJ, Kalitzeos A, Kane TM, Singh N, Kreis J, Pennesi ME, Hardcastle AJ, Neitz J, Neitz M, Michaelides M, Carroll J. Foveal Cone Structure in Patients With Blue Cone Monochromacy. Invest Ophthalmol Vis Sci 2022; 63:23. [PMID: 36301530 PMCID: PMC9624264 DOI: 10.1167/iovs.63.11.23] [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: 04/04/2022] [Accepted: 09/22/2022] [Indexed: 11/24/2022] Open
Abstract
Purpose Blue cone monochromacy (BCM) is a rare inherited cone disorder in which both long- (L-) and middle- (M-) wavelength sensitive cone classes are either impaired or nonfunctional. Assessing genotype-phenotype relationships in BCM can improve our understanding of retinal development in the absence of functional L- and M-cones. Here we examined foveal cone structure in patients with genetically-confirmed BCM, using adaptive optics scanning light ophthalmoscopy (AOSLO). Methods Twenty-three male patients (aged 6-75 years) with genetically-confirmed BCM were recruited for high-resolution imaging. Eight patients had a deletion of the locus control region (LCR), and 15 had a missense mutation-Cys203Arg-affecting the first two genes in the opsin gene array. Foveal cone structure was assessed using confocal and non-confocal split-detection AOSLO across a 300 × 300 µm area, centered on the location of peak cell density. Results Only one of eight patients with LCR deletions and 10 of 15 patients with Cys203Arg mutations had analyzable images. Mean total cone density for Cys203Arg patients was 16,664 ± 11,513 cones/mm2 (n = 10), which is, on average, around 40% of normal. Waveguiding cone density was 2073 ± 963 cones/mm2 (n = 9), which was consistent with published histological estimates of S-cone density in the normal eye. The one patient with an LCR deletion had a total cone density of 10,246 cones/mm2 and waveguiding density of 1535 cones/mm2. Conclusions Our results show that BCM patients with LCR deletions and Cys203Arg mutations have a population of non-waveguiding photoreceptors, although the spectral identity and level of function remain unknown.
Collapse
Affiliation(s)
- Emily J. Patterson
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
| | - Angelos Kalitzeos
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
| | - Thomas M. Kane
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
| | - Navjit Singh
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
| | - Joseph Kreis
- Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Mark E. Pennesi
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Alison J. Hardcastle
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
| | - Jay Neitz
- Ophthalmology, University of Washington, Seattle, Washington, United States
| | - Maureen Neitz
- Ophthalmology, University of Washington, Seattle, Washington, United States
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
| | - Joseph Carroll
- Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| |
Collapse
|
28
|
Bedggood P, Britten-Jones AC, Ayton LN, Metha A. Assessment of photoreceptor function with ultrafast retinal densitometry. BIOMEDICAL OPTICS EXPRESS 2022; 13:5311-5326. [PMID: 36425640 PMCID: PMC9664880 DOI: 10.1364/boe.472174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 08/26/2022] [Accepted: 08/26/2022] [Indexed: 05/02/2023]
Abstract
The optical density of visual pigment can be measured by imaging the dark-adapted eye while bleaching with visible light. This measurement can be made for individual photoreceptor cells using adaptive optics; however, activation of the phototransduction cascade imparts rapid changes in phase that modulate the signal via optical interference. This limits utility because data must be averaged over many experimental runs. Here we used a "flood" illuminated adaptive optics system at 4000 fps, bright light to achieve rapid bleaching, and broad illumination bandwidth to mitigate interference effects. Data were super-resolved using the natural motion of the eye to overcome the reduced pixel resolution of the ultrafast camera. This approach was applied to classify the trichromatic cone photoreceptor mosaic at a single fixation locus within the foveal region of 3 healthy subjects. Subjects were dark adapted for 6 minutes to replenish cone photopigment. This was followed either directly by imaging at 555 ± 50 nm, or by first pre-adapting the retina to 700 nm light to preferentially deplete "L" cone pigment. A total of 3,252 cones were classified as either "S", "M", or "L" type based on clustering of the intensity data observed under these two conditions. Mean classification probability ranged from 99.3 to 99.8%, with individual cell probabilities exceeding 95% in 97.0 to 99.2% of cones. Accuracy of cone classification peaked when using the first 10-30 ms of data, with significant reductions in accuracy noted with the inclusion of data from later times. Our results show that rapid bleaching and data acquisition significantly improve the robustness of cell-resolved densitometry.
Collapse
Affiliation(s)
- Phillip Bedggood
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville, Australia
| | - Alexis Ceecee Britten-Jones
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
| | - Lauren N. Ayton
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
- Department of Surgery (Ophthalmology), The University of Melbourne, East Melbourne, Australia
| | - Andrew Metha
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville, Australia
| |
Collapse
|
29
|
Human cone elongation responses can be explained by photoactivated cone opsin and membrane swelling and osmotic response to phosphate produced by RGS9-catalyzed GTPase. Proc Natl Acad Sci U S A 2022; 119:e2202485119. [PMID: 36122241 PMCID: PMC9522364 DOI: 10.1073/pnas.2202485119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Optical coherence tomography has established that human cone photoreceptor outer segments elongate in response to stimuli bleaching large fractions of their visual pigment. Elongation responses are completely described over their 200-fold bleaching range as the sum of two exponentially rising components differing 13-fold in time constants and 4-fold in light sensitivity. Bleaching measurements of individual cones with adaptive optics scanning laser ophthalmoscopy (SLO) suggest that component 2 arises from cone opsin and disk membrane swelling triggered by photoactivation. Application of a model of phototransduction suggests that component 1 corresponds to free phosphate generated by regulator of G-protein signaling 9 (RGS9)-catalyzed hydrolysis of guanosine triphosphate (GTP) in the α-subunit of G protein complexed with phosphodiesterase. Human cone outer segment (COS) length changes in response to stimuli bleaching up to 99% of L- and M-cone opsins were measured with high resolution, phase-resolved optical coherence tomography (OCT). Responses comprised a fast phase (∼5 ms), during which COSs shrink, and two slower phases (1.5 s), during which COSs elongate. The slower components saturated in amplitude (∼425 nm) and initial rate (∼3 nm ms−1) and are well described over the 200-fold bleaching range as the sum of two exponentially rising functions with time constants of 80 to 90 ms (component 1) and 1,000 to 1,250 ms (component 2). Measurements with adaptive optics reflection densitometry revealed component 2 to be linearly related to cone pigment bleaching, and the hypothesis is proposed that it arises from cone opsin and disk membrane swelling triggered by isomerization and rate-limited by chromophore hydrolysis and its reduction to membrane-localized all-trans retinol. The light sensitivity and kinetics of component 1 suggested that the underlying mechanism is an osmotic response to an amplified soluble by-product of phototransduction. The hypotheses that component 1 corresponds to G-protein subunits dissociating from the membrane, metabolites of cyclic guanosine monophosphate (cGMP) hydrolysis, or by-products of activated guanylate cyclase are rejected, while the hypothesis that it corresponds to phosphate produced by regulator of G-protein signaling 9 (RGS9)-catalyzed hydrolysis of guanosine triphosphate (GTP) in G protein–phosphodiesterase complexes was found to be consistent with the results. These results provide a basis for the assessment with optoretinography of phototransduction in individual cone photoreceptors in health and during disease progression and therapeutic interventions.
Collapse
|
30
|
Samimi K, Pattnaik BR, Capowski EE, Saha K, Gamm DM, Skala MC. In situ autofluorescence lifetime assay of a photoreceptor stimulus response in mouse retina and human retinal organoids. BIOMEDICAL OPTICS EXPRESS 2022; 13:3476-3492. [PMID: 35781966 PMCID: PMC9208582 DOI: 10.1364/boe.455783] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/25/2022] [Accepted: 05/05/2022] [Indexed: 06/15/2023]
Abstract
Photoreceptors are the key functional cell types responsible for the initiation of vision in the retina. Phototransduction involves isomerization and conversion of vitamin A compounds, known as retinoids, and their recycling through the visual cycle. We demonstrate a functional readout of the visual cycle in photoreceptors within stem cell-derived retinal organoids and mouse retinal explants based on spectral and lifetime changes in autofluorescence of the visual cycle retinoids after exposure to light or chemical stimuli. We also apply a simultaneous two- and three-photon excitation method that provides specific signals and increases contrast between these retinoids, allowing for reliable detection of their presence and conversion within photoreceptors. This multiphoton imaging technique resolves the slow dynamics of visual cycle reactions and can enable high-throughput functional screening of retinal tissues and organoid cultures with single-cell resolution.
Collapse
Affiliation(s)
- Kayvan Samimi
- Morgridge Institute for Research, Madison, WI 53715, USA
| | - Bikash R. Pattnaik
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI 53705, USA
- Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53706, USA
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | | | - Krishanu Saha
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI 53705, USA
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI 53715, USA
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - David M. Gamm
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI 53705, USA
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Melissa C. Skala
- Morgridge Institute for Research, Madison, WI 53715, USA
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI 53705, USA
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| |
Collapse
|
31
|
Giannini JP, Lu R, Bower AJ, Fariss R, Tam J. Visualizing retinal cells with adaptive optics imaging modalities using a translational imaging framework. BIOMEDICAL OPTICS EXPRESS 2022; 13:3042-3055. [PMID: 35774328 PMCID: PMC9203084 DOI: 10.1364/boe.454560] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 04/08/2022] [Accepted: 04/08/2022] [Indexed: 05/18/2023]
Abstract
Adaptive optics reflectance-based retinal imaging has proved a valuable tool for the noninvasive visualization of cells in the living human retina. Many subcellular features that remain at or below the resolution limit of current in vivo techniques may be more easily visualized with the same modalities in an ex vivo setting. While most microscopy techniques provide significantly higher resolution, enabling the visualization of fine cellular detail in ex vivo retinal samples, they do not replicate the reflectance-based imaging modalities of in vivo retinal imaging. Here, we introduce a strategy for imaging ex vivo samples using the same imaging modalities as those used for in vivo retinal imaging, but with increased resolution. We also demonstrate the ability of this approach to perform protein-specific fluorescence imaging and reflectance imaging simultaneously, enabling the visualization of nearly transparent layers of the retina and the classification of cone photoreceptor types.
Collapse
|
32
|
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.
Collapse
|
33
|
Kim TH, Ma G, Son T, Yao X. Functional Optical Coherence Tomography for Intrinsic Signal Optoretinography: Recent Developments and Deployment Challenges. Front Med (Lausanne) 2022; 9:864824. [PMID: 35445037 PMCID: PMC9013890 DOI: 10.3389/fmed.2022.864824] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 03/16/2022] [Indexed: 11/13/2022] Open
Abstract
Intrinsic optical signal (IOS) imaging of the retina, also termed as optoretinogram or optoretinography (ORG), promises a non-invasive method for the objective assessment of retinal function. By providing the unparalleled capability to differentiate individual retinal layers, functional optical coherence tomography (OCT) has been actively investigated for intrinsic signal ORG measurements. However, clinical deployment of functional OCT for quantitative ORG is still challenging due to the lack of a standardized imaging protocol and the complication of IOS sources and mechanisms. This article aims to summarize recent developments of functional OCT for ORG measurement, OCT intensity- and phase-based IOS processing. Technical challenges and perspectives of quantitative IOS analysis and ORG interpretations are discussed.
Collapse
Affiliation(s)
- Tae-Hoon Kim
- Richard and Loan Hill Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, United States
| | - Guangying Ma
- Richard and Loan Hill Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, United States
| | - Taeyoon Son
- Richard and Loan Hill Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, United States
| | - Xincheng Yao
- Richard and Loan Hill Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, United States
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, United States
| |
Collapse
|
34
|
Tomczewski S, Węgrzyn P, Borycki D, Auksorius E, Wojtkowski M, Curatolo A. Light-adapted flicker optoretinograms captured with a spatio-temporal optical coherence-tomography (STOC-T) system. BIOMEDICAL OPTICS EXPRESS 2022; 13:2186-2201. [PMID: 35519256 PMCID: PMC9045926 DOI: 10.1364/boe.444567] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 02/20/2022] [Accepted: 02/23/2022] [Indexed: 06/14/2023]
Abstract
For many years electroretinography (ERG) has been used for obtaining information about the retinal physiological function. More recently, a new technique called optoretinography (ORG) has been developed. In one form of this technique, the physiological response of retinal photoreceptors to visible light, resulting in a nanometric photoreceptor optical path length change, is measured by phase-sensitive optical coherence tomography (OCT). To date, a limited number of studies with phase-based ORG measured the retinal response to a flickering light stimulation. In this work, we use a spatio-temporal optical coherence tomography (STOC-T) system to capture optoretinograms with a flickering stimulus over a 1.7 × 0.85 mm2 area of a light-adapted retina located between the fovea and the optic nerve. We show that we can detect statistically-significant differences in the photoreceptor optical path length (OPL) modulation amplitudes in response to different flicker frequencies and with better signal to noise ratios (SNRs) than for a dark-adapted eye. We also demonstrate the ability to spatially map such response to a patterned stimulus with light stripes flickering at different frequencies, highlighting the prospect of characterizing the spatially-resolved temporal-frequency response of the retina with ORG.
Collapse
Affiliation(s)
- Sławomir Tomczewski
- International Centre for Translational Eye Research, Skierniewicka 10A, 01-230, Warszawa, Poland
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warszawa, Poland
- Equal contributors
| | - Piotr Węgrzyn
- International Centre for Translational Eye Research, Skierniewicka 10A, 01-230, Warszawa, Poland
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warszawa, Poland
- Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warszawa, Poland
- Equal contributors
| | - Dawid Borycki
- International Centre for Translational Eye Research, Skierniewicka 10A, 01-230, Warszawa, Poland
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warszawa, Poland
| | - Egidijus Auksorius
- International Centre for Translational Eye Research, Skierniewicka 10A, 01-230, Warszawa, Poland
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warszawa, Poland
- Center for Physical Sciences and Technology (FTMC), Saulėtekio al. 3, LT-10257 Vilnius, Lithuania
| | - Maciej Wojtkowski
- International Centre for Translational Eye Research, Skierniewicka 10A, 01-230, Warszawa, Poland
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warszawa, Poland
| | - Andrea Curatolo
- International Centre for Translational Eye Research, Skierniewicka 10A, 01-230, Warszawa, Poland
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warszawa, Poland
| |
Collapse
|
35
|
Zhang L, Dong R, Zawadzki RJ, Zhang P. Volumetric data analysis enabled spatially resolved optoretinogram to measure the functional signals in the living retina. JOURNAL OF BIOPHOTONICS 2022; 15:e202100252. [PMID: 34817116 PMCID: PMC8901551 DOI: 10.1002/jbio.202100252] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 10/21/2021] [Accepted: 11/22/2021] [Indexed: 05/05/2023]
Abstract
Optoretinogram, a technique in which optical coherence tomography (OCT) is used to measure retinal functions in response to a visible light stimulus, can be a potentially useful tool to quantify retinal health alterations. Existing experimental studies on animals have focused on measuring the global retinal response by transversally averaging 3D data across the retina, which minimizes the spatial resolution of the signals, and limits the signal-to-noise ratio because only central B-scans are collected and analyzed. These problems were addressed in this study by collecting volumetric data to probe functional signals and developing an improved 3D registration approach to align such series-acquired OCT volumes. These data were then divided into small blocks and subject to a spatiotemporal analysis, whose results confirmed the spatial-dependence of functional signals. By further averaging, the overall measurement accuracies for the position and the scattering signals were estimated to be approximately 30 nm and 1.1 %, respectively. With improved accuracy, this method revealed certain novel functional signals that have not been previously reported. In conclusion, this work provides a powerful tool to monitor retinal local and global functional changes in aging, diseased, or treated rodent eyes.
Collapse
Affiliation(s)
- Lijie Zhang
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, 116024, China
| | - Rongyao Dong
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, 116024, China
| | - Robert J. Zawadzki
- UC Davis Eye-Pod Small Animals Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, California, 95616, United States
- UC Davis Eye Center, Department of Ophthalmology & Vision Science, University of California Davis, Sacramento, California, 95817, United States
| | - Pengfei Zhang
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, 116024, China
- UC Davis Eye-Pod Small Animals Ocular Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, California, 95616, United States
- Correspondence: Pengfei Zhang, Dalian University of Technology, 116024, China,
| |
Collapse
|
36
|
Bensinger E, Wang Y, Roorda A. Patches of Dysflective Cones in Eyes With No Known Disease. Invest Ophthalmol Vis Sci 2022; 63:29. [PMID: 35072690 PMCID: PMC8802026 DOI: 10.1167/iovs.63.1.29] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Purpose To characterize the structure and function of patches of dysflective cones in the foveal region of subjects with normal vision and no known pathology. Dysflective cones are cones that have little or no reflective properties in optical coherence tomography (OCT) or adaptive optics scanning laser ophthalmoscope (AOSLO) images yet exhibit measurable function. Methods AOSLO images were surveyed for the presence of hyporeflective cone patches, and subjects were brought back for imaging to determine the changes in the hyporeflective region. Adaptive optics microperimetry (AOMP) was used to assess the function of hyporeflective patches in four subjects to determine that they did, in fact, contain dysflective cones. AOMP utilized a stimulus size of less than 1 arcmin to measure thresholds inside and outside the hyporeflective region. Results Nineteen out of 47 individuals retrospectively reviewed had one or more regions with hyporeflective cone patches in one or both eyes. Ten subjects with hyporeflective cone patches were brought back for imaging. Seven of the 10 had resolved at follow up, and in three subjects new hyporeflective patches appeared in a different location. All AOMP-measured subjects had measurable function in the dysflective cone region. Three out of four subjects showed no difference in light sensitivity in the dysflective region compared to adjacent areas, and one subject showed a 3× reduction in sensitivity in the area. Conclusions Patches of dysflective cone have been identified in subjects with normal vision and no known pathology, and we have observed instances where dysflective cones in these subjects regain normal reflective properties.
Collapse
Affiliation(s)
- Ethan Bensinger
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, California, United States
| | - Yiyi Wang
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, California, United States
| | - Austin Roorda
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, California, United States
| |
Collapse
|
37
|
|
38
|
The Impact of the Spectral Radiation Environment on the Maximum Absorption Wavelengths of Human Vision and Other Species. Life (Basel) 2021; 11:life11121337. [PMID: 34947867 PMCID: PMC8707699 DOI: 10.3390/life11121337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 11/29/2021] [Accepted: 11/30/2021] [Indexed: 12/04/2022] Open
Abstract
Since the earliest development of the eye (and vision) around 530 million years ago (Mya), it has evolved, adapting to different habitats, species, and changing environmental conditions on Earth. We argue that a radiation environment determined by the atmosphere played a determining role in the evolution of vision, specifically on the human eye, which has three vision regimes (photopic-, scotopic-, and mesopic vision) for different illumination conditions. An analysis of the irradiance spectra, reaching the shallow ocean depths, revealed that the available radiation could have determined the bandwidth of the precursor to vision systems, including human vision. We used the radiative transfer model to test the existing hypotheses on human vision. We argue that, once on the surface, the human photopic (daytime) and scotopic (night-time) vision followed different evolutionary directions, maximum total energy, and optimum information, respectively. Our analysis also suggests that solar radiation reflected from the moon had little or no influence on the evolution of scotopic vision. Our results indicate that, apart from human vision, the vision of only a few birds, rodents, and deep-sea fish are strongly correlated to the available radiation within their respective habitats.
Collapse
|
39
|
Daich Varela M, Esener B, Hashem SA, Cabral de Guimaraes TA, Georgiou M, Michaelides M. Structural evaluation in inherited retinal diseases. Br J Ophthalmol 2021; 105:1623-1631. [PMID: 33980508 PMCID: PMC8639906 DOI: 10.1136/bjophthalmol-2021-319228] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/07/2021] [Accepted: 04/21/2021] [Indexed: 12/20/2022]
Abstract
Ophthalmic genetics is a field that has been rapidly evolving over the last decade, mainly due to the flourishing of translational medicine for inherited retinal diseases (IRD). In this review, we will address the different methods by which retinal structure can be objectively and accurately assessed in IRD. We review standard-of-care imaging for these patients: colour fundus photography, fundus autofluorescence imaging and optical coherence tomography (OCT), as well as higher-resolution and/or newer technologies including OCT angiography, adaptive optics imaging, fundus imaging using a range of wavelengths, magnetic resonance imaging, laser speckle flowgraphy and retinal oximetry, illustrating their utility using paradigm genotypes with on-going therapeutic efforts/trials.
Collapse
Affiliation(s)
- Malena Daich Varela
- Moorfields Eye Hospital City Road Campus, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Burak Esener
- Department of Ophthalmology, Inonu University School of Medicine, Malatya, Turkey
| | - Shaima A Hashem
- Moorfields Eye Hospital City Road Campus, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | | | - Michalis Georgiou
- Moorfields Eye Hospital City Road Campus, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Michel Michaelides
- Moorfields Eye Hospital City Road Campus, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| |
Collapse
|
40
|
Pijewska E, Zhang P, Meina M, Meleppat RK, Szkulmowski M, Zawadzki RJ. Extraction of phase-based optoretinograms (ORG) from serial B-scans acquired over tens of seconds by mouse retinal raster scanning OCT system. BIOMEDICAL OPTICS EXPRESS 2021; 12:7849-7871. [PMID: 35003871 PMCID: PMC8713677 DOI: 10.1364/boe.439900] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 11/01/2021] [Accepted: 11/08/2021] [Indexed: 06/14/2023]
Abstract
Several specialized retinal optical coherence tomography (OCT) acquisition and processing methods have been recently developed to allow in vivo probing of light-evoked photoreceptors function, focusing on measurements in individual photoreceptors (rods and cones). Recent OCT investigations in humans and experimental animals have shown that the outer segments in dark-adapted rods and cones elongate in response to the visible optical stimuli that bleach fractions of their visual photopigment. We have previously successfully contributed to these developments by implementing OCT intensity-based "optoretinograms" (ORG), the paradigm of using near-infrared OCT (NIR OCT) to measure bleaching-induced back-scattering and/or elongation changes of photoreceptors in the eye in vivo. In parallel, several groups have successfully implemented phase-based ORGs, mainly in human studies, exploiting changes in the phases of back-scattered light. This allowed more sensitive observations of tiny alterations of photoreceptors structures. Applications of the phase-based ORG have been implemented primarily in high speed and cellular resolution AO-OCT systems that can visualize photoreceptor mosaic, allowing phase measurements of path length changes in outer segments of individual photoreceptors. The phase-based ORG in standard resolution OCT systems is much more demanding to implement and has not been explored extensively. This manuscript describes our efforts to implement a phase analysis framework to retinal images acquired with a standard resolution and raster scanning OCT system, which offers much lower phase stability than line-field or full-field OCT detection schemes due to the relatively slower acquisition speed. Our initial results showcase the successful extraction of phase-based ORG signal from the B-scans acquired at ∼100 Hz rate and its favorable comparison with intensity-based ORG signal extracted from the same data sets. We implemented the calculation of phase-based ORG signals using Knox-Thompson paths and modified signal recovery by adding decorrelation weights. The phase-sensitive ORG signal analysis developed here for mouse retinal raster scanning OCT systems could be in principle extended to clinical retinal raster scanning OCT systems, potentially opening doors for clinically friendly ORG probing.
Collapse
Affiliation(s)
- Ewelina Pijewska
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziądzka 5, 87-100 Torun, Poland
| | - Pengfei Zhang
- UC Davis Eyepod Imaging Laboratory, Dept. of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, USA
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, No. 2 Linggong Road, Ganjingzi District, Dalian City, Liaoning Province 116024, China
| | - Michał Meina
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziądzka 5, 87-100 Torun, Poland
| | - Ratheesh K. Meleppat
- UC Davis Eyepod Imaging Laboratory, Dept. of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, USA
| | - Maciej Szkulmowski
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziądzka 5, 87-100 Torun, Poland
| | - Robert J. Zawadzki
- UC Davis Eyepod Imaging Laboratory, Dept. of Cell Biology and Human Anatomy, University of California Davis, 4320 Tupper Hall, Davis, CA 95616, USA
- Department of Ophthalmology & Vision Science, University of California Davis, 4860 Y Street Suite 2400 Sacramento, CA 95817, USA
| |
Collapse
|
41
|
Cone photoreceptor dysfunction in retinitis pigmentosa revealed by optoretinography. Proc Natl Acad Sci U S A 2021; 118:2107444118. [PMID: 34795055 PMCID: PMC8617487 DOI: 10.1073/pnas.2107444118] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2021] [Indexed: 12/20/2022] Open
Abstract
Many blinding diseases afflict photoreceptors, specialized cells in the retina that capture and transduce light to initiate vision. Biomarkers that are sensitive to photoreceptor health are crucial for early detection and effective treatment monitoring of these diseases yet remain elusive. Here, we develop an optical biomarker, based on optoretinographic photoreceptor responses to light stimulation, that reflects the degree of dysfunction of individual cone photoreceptors in patients with retinitis pigmentosa (RP), the most common inherited retinal degenerative disease. Our results show that this biomarker may be beneficial for assessing the functionality of remaining retinal cells in RP patients and for assessing efficacy of treatments such as gene therapy and stem cell transplantation for RP and other diseases afflicting photoreceptors. Retinitis pigmentosa (RP) is the most common group of inherited retinal degenerative diseases, whose most debilitating phase is cone photoreceptor death. Perimetric and electroretinographic methods are the gold standards for diagnosing and monitoring RP and assessing cone function. However, these methods lack the spatial resolution and sensitivity to assess disease progression at the level of individual photoreceptor cells, where the disease originates and whose degradation causes vision loss. High-resolution retinal imaging methods permit visualization of human cone cells in vivo but have only recently achieved sufficient sensitivity to observe their function as manifested in the cone optoretinogram. By imaging with phase-sensitive adaptive optics optical coherence tomography, we identify a biomarker in the cone optoretinogram that characterizes individual cone dysfunction by stimulating cone cells with flashes of light and measuring nanometer-scale changes in their outer segments. We find that cone optoretinographic responses decrease with increasing RP severity and that even in areas where cone density appears normal, cones can respond differently than those in controls. Unexpectedly, in the most severely diseased patches examined, we find isolated cones that respond normally. Short-wavelength–sensitive cones are found to be more vulnerable to RP than medium- and long-wavelength–sensitive cones. We find that decreases in cone response and cone outer-segment length arise earlier in RP than changes in cone density but that decreases in response and length are not necessarily correlated within single cones.
Collapse
|
42
|
Carrick FR, Azzolino SF, Hunfalvay M, Pagnacco G, Oggero E, D’Arcy RCN, Abdulrahman M, Sugaya K. The Pupillary Light Reflex as a Biomarker of Concussion. Life (Basel) 2021; 11:life11101104. [PMID: 34685475 PMCID: PMC8537991 DOI: 10.3390/life11101104] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/28/2021] [Accepted: 10/12/2021] [Indexed: 11/16/2022] Open
Abstract
The size of our pupils changes continuously in response to variations in ambient light levels, a process known as the pupillary light reflex (PLR). The PLR is not a simple reflex as its function is modulated by cognitive brain function and any long-term changes in brain function secondary to injury should cause a change in the parameters of the PLR. We performed a retrospective clinical review of the PLR of our patients using the BrightLamp Reflex iPhone app. The PLR variables of latency, maximum pupil diameter (MaxPD), minimum pupil diameter (MinPD), maximum constriction velocity (MCV), and the 75% recovery time (75% PRT) were associated with significant differences between subjects who had suffered a concussion and those that had not. There were also significant differences in PLR metrics over the life span and between genders and those subjects with and without symptoms. The differences in PLR metrics are modulated not only by concussion history but also by gender and whether or not the person has symptoms associated with a head injury. A concussive injury to the brain is associated with changes in the PLR that persist over the life span, representing biomarkers that might be used in clinical diagnosis, treatment, and decision making.
Collapse
Affiliation(s)
- Frederick Robert Carrick
- College of Medicine, University of Central Florida, Orlando, FL 32816, USA;
- Burnett School of Biomedical Science, University of Central Florida, Orlando, FL 32816, USA
- MGH Institute for Health Professions, Boston, MA 02129, USA
- Centre for Mental Health Research in Association with University of Cambridge, Cambridge CB2 1TN, UK
- Carrick Institute, Cape Canaveral, FL 32920, USA; (S.F.A.); (M.H.); (G.P.); (E.O.)
- Correspondence:
| | - Sergio F. Azzolino
- Carrick Institute, Cape Canaveral, FL 32920, USA; (S.F.A.); (M.H.); (G.P.); (E.O.)
| | - Melissa Hunfalvay
- Carrick Institute, Cape Canaveral, FL 32920, USA; (S.F.A.); (M.H.); (G.P.); (E.O.)
| | - Guido Pagnacco
- Carrick Institute, Cape Canaveral, FL 32920, USA; (S.F.A.); (M.H.); (G.P.); (E.O.)
- Department of Electrical and Computer Engineering, University of Wyoming, Laramie, WY 82071, USA
| | - Elena Oggero
- Carrick Institute, Cape Canaveral, FL 32920, USA; (S.F.A.); (M.H.); (G.P.); (E.O.)
- Department of Electrical and Computer Engineering, University of Wyoming, Laramie, WY 82071, USA
| | - Ryan C. N. D’Arcy
- BrainNET, Health and Technology District, Vancouver, BC V3V 0C6, Canada;
- Centre for Neurology Studies, HealthTech Connex, Vancouver, BC V3V 0C6, Canada
- DM Centre for Brain Health, Department of Radiology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Mahera Abdulrahman
- Health Informatics and Smart Health Department, Health Regulation Sector, Dubai Health Authority, Dubai 7272, United Arab Emirates;
| | - Kiminobu Sugaya
- College of Medicine, University of Central Florida, Orlando, FL 32816, USA;
- Burnett School of Biomedical Science, University of Central Florida, Orlando, FL 32816, USA
| |
Collapse
|
43
|
Lee KE, Heitkotter H, Carroll J. Challenges Associated With Ellipsoid Zone Intensity Measurements Using Optical Coherence Tomography. Transl Vis Sci Technol 2021; 10:27. [PMID: 34665233 PMCID: PMC8543396 DOI: 10.1167/tvst.10.12.27] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 09/16/2021] [Indexed: 12/11/2022] Open
Abstract
Translational Relevance Qualitative evaluation of the ellipsoid zone band on optical coherence tomography is a valuable clinical tool for assessing photoreceptor structure, though more quantitative metrics are emerging. Awareness of the challenges involved in interpreting quantitative metrics is important for their clinical translation.
Collapse
Affiliation(s)
- Karen E. Lee
- Medical College of Wisconsin, Milwaukee, WI, USA
| | - Heather Heitkotter
- Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Joseph Carroll
- Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
- Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| |
Collapse
|
44
|
Brais-Brunet S, Heckel É, Kanniyappan U, Chemtob S, Boudoux C, Joyal JS, Dehaes M. Morphometric and Microstructural Changes During Murine Retinal Development Characterized Using In Vivo Optical Coherence Tomography. Invest Ophthalmol Vis Sci 2021; 62:20. [PMID: 34698774 PMCID: PMC8556565 DOI: 10.1167/iovs.62.13.20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Purpose The purpose of this study was to develop an in vivo optical coherence tomography (OCT) system capable of imaging the developing mouse retina and its associated morphometric and microstructural changes. Methods Thirty-four wild-type mice (129S1/SvlmJ) were anesthetized and imaged between postnatal (P) day 7 and P21. OCT instrumentation was developed to optimize signal intensity and image quality. Semi-automatic segmentation tools were developed to quantify the retinal thickness of the nerve fiber layer (NFL), inner plexiform layer (IPL), inner nuclear layer (INL), and the outer retinal layers (ORL), in addition to the total retina. The retinal maturation was characterized by comparing layer thicknesses between consecutive time points. Results From P7 to P10, the IPL increased significantly, consistent with retinal synaptogenesis. From P10 to P12, the IPL and ORL also increased, which is coherent with synaptic connectivity and photoreceptor maturation. In contrast, during these periods, the INL decreased significantly, consistent with cellular densification and selective apoptotic “pruning” of the tissue during nuclear migration. Thereafter from P12 to P21, the INL continued to thin (significantly from P17 to P21) whereas the other layers remained unchanged. No time-dependent changes were observed in the NFL. Overall, changes in the total retina were attributed to those in the IPL, INL, and ORL. Regions of the retina adjacent to the optic nerve head were thinner than distal regions during maturation. Conclusions Changes in retinal layer thickness are consistent with retinal developmental mechanisms. Accordingly, this report opens new horizons in using our system in the mouse to characterize longitudinally developmental digressions in models of human diseases.
Collapse
Affiliation(s)
- Simon Brais-Brunet
- Institute of Biomedical Engineering, University of Montréal, Montréal, Canada.,Research Center, CHU Sainte-Justine, Montréal, Canada
| | - Émilie Heckel
- Research Center, CHU Sainte-Justine, Montréal, Canada.,Department of Pharmacology, University of Montréal, Montréal, Canada
| | - Udayakumar Kanniyappan
- Institute of Biomedical Engineering, University of Montréal, Montréal, Canada.,Research Center, CHU Sainte-Justine, Montréal, Canada
| | - Sylvain Chemtob
- Research Center, CHU Sainte-Justine, Montréal, Canada.,Department of Pharmacology, University of Montréal, Montréal, Canada.,Department of Pediatrics, University of Montréal, Montréal, Canada.,Department of Ophthalmology, University of Montréal, Montréal, Canada
| | - Caroline Boudoux
- Research Center, CHU Sainte-Justine, Montréal, Canada.,Department of Engineering Physics, Polytechnique Montréal, Montréal, Canada
| | - Jean-Sébastien Joyal
- Research Center, CHU Sainte-Justine, Montréal, Canada.,Department of Pharmacology, University of Montréal, Montréal, Canada.,Department of Pediatrics, University of Montréal, Montréal, Canada.,Department of Ophthalmology, University of Montréal, Montréal, Canada
| | - Mathieu Dehaes
- Institute of Biomedical Engineering, University of Montréal, Montréal, Canada.,Research Center, CHU Sainte-Justine, Montréal, Canada.,Department of Radiology, Radio-oncology and Nuclear Medicine, University of Montréal, Montréal, Canada
| |
Collapse
|
45
|
Jonnal RS. Toward a clinical optoretinogram: a review of noninvasive, optical tests of retinal neural function. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:1270. [PMID: 34532407 PMCID: PMC8421939 DOI: 10.21037/atm-20-6440] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 07/12/2021] [Indexed: 11/17/2022]
Abstract
The past few years have witnessed rapid development of the optoretinogram—a noninvasive, optical measurement of neural function in the retina, and especially the photoreceptors (Ph). While its recent development has been rapid, it represents the culmination of hundreds of experiments spanning decades. Early work showed measurable and reproducible changes in the optical properties of retinal explants and suspensions of Ph, and uncovered some of the biophysical and biochemical mechanisms underlying them. That work thus provided critical motivation for more recent work based on clinical imaging platforms, whose eventual goal is the improvement of ophthalmic care and streamlining the discovery of novel therapeutics. The first part of this review consists of a selective summary of the early work, and identifies four kinds of stimulus-evoked optical signals that have emerged from it: changes in light scattered from the membranous discs of the Ph’s outer segment (OS), changes in light scattered by the front and back boundaries of the OS, rearrangement of scattering material in and near the OS, and changes in the OS length. In the past decade, all four of these signals have continued to be investigated using imaging systems already used in the clinic or intended for clinical and translational use. The second part of this review discusses these imaging modalities, their potential to detect and quantify the signals of interest, and other factors influencing their translational promise. Particular attention is paid to phase-sensitive optical coherence tomography (OCT) with adaptive optics (AO), a method in which both the amplitude and the phase of light reflected from individual Ph is monitored as visible stimuli are delivered to them. The record of the light’s phase is decoded to reveal a reproducible pattern of deformation in the OS, while the amplitude reveals changes in scattering and structural rearrangements. The method has been demonstrated in a few labs and has been used to measure responses from both rods and cones. With the ability to detect responses to stimuli isomerizing less than 0.01% of photopigment, this technique may prove to be a quick, noninvasive, and objective way to measure subtle disease-related dysfunction at the cellular level, and thus to provide an entirely new and complementary biomarker for retinal disease and recovery.
Collapse
Affiliation(s)
- Ravi S Jonnal
- Department of Ophthalmology and Vision Science, University of California, Davis, CA, USA
| |
Collapse
|
46
|
Kadomoto S, Muraoka Y, Uji A, Ooto S, Kawai K, Ishikura M, Nishigori N, Akagi T, Tsujikawa A. Human Foveal Cone and Müller Cells Examined by Adaptive Optics Optical Coherence Tomography. Transl Vis Sci Technol 2021; 10:17. [PMID: 34559184 PMCID: PMC8475288 DOI: 10.1167/tvst.10.11.17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Purpose The purpose of this study was to image and investigate the foveal microstructure of human cone and Müller cells using adaptive optics-optical coherence tomography. Methods Six healthy subjects underwent the prototype adaptive optics-optical coherence tomography imaging, which allowed an axial resolution of 3.4 µm and a transverse resolution of approximately 3 µm. The morphological features of the individual retinal cells observed in the foveola were qualitatively and quantitatively evaluated. Results In the six healthy subjects, the image B-scans showed hyper-reflective dots that were densely packed in the outer nuclear layer. The mean number, diameter, and density of hyper-reflective dots in the foveola were 250.8 ± 59.6, 12.7 ± 59.6 µm, and 6966 ± 1833/mm2, respectively. These qualitative and quantitative findings regarding the hyper-reflective dots were markedly consistent with the morphological features of the foveal cone cell nuclei. Additionally, the images showed the funnel-shaped hyporeflective bodies running vertically and obliquely between the inner and external limiting membranes, illustrating the cell morphology of the foveal Müller cells. Conclusions Using adaptive optics, we succeeded in visualizing cross-sectional images of the individual cone and Müller cells of the human retina in vivo. Translational Relevance Adaptive optics-optical coherence tomography would help to improve our understanding of the pathogenesis of macular diseases.
Collapse
Affiliation(s)
- Shin Kadomoto
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Yuki Muraoka
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Akihito Uji
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Sotaro Ooto
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Kentaro Kawai
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Masaharu Ishikura
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Naomi Nishigori
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Tadamichi Akagi
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Akitaka Tsujikawa
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| |
Collapse
|
47
|
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.
Collapse
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
| |
Collapse
|
48
|
Zhang F, Kurokawa K, Bernucci MT, Jung HW, Lassoued A, Crowell JA, Neitz J, Neitz M, Miller DT. Revealing How Color Vision Phenotype and Genotype Manifest in Individual Cone Cells. Invest Ophthalmol Vis Sci 2021; 62:8. [PMID: 33544131 PMCID: PMC7873503 DOI: 10.1167/iovs.62.2.8] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Purpose Psychophysical and genetic testing provide substantial information about color vision phenotype and genotype. However, neither reveals how color vision phenotypes and genotypes manifest themselves in individual cones, where color vision and its anomalies are thought to originate. Here, we use adaptive-optics phase-sensitive optical coherence tomography (AO-PSOCT) to investigate these relationships. Methods We used AO-PSOCT to measure cone function—optical response to light stimulation—in each of 16 human subjects with different phenotypes and genotypes of color vision (five color-normal, three deuteranopic, two protanopic, and six deuteranomalous trichromatic subjects). We classified three spectral types of cones (S, M, and L), and we measured cone structure—namely cone density, cone mosaic arrangement, and spatial arrangement of cone types. Results For the different phenotypes, our cone function results show that (1) color normals possess S, M, and L cones; (2) deuteranopes are missing M cones but are normal otherwise; (3) protanopes are missing L cones but are normal otherwise; and (4) deuteranomalous trichromats are missing M cones but contain evidence of at least two subtypes of L cones. Cone function was consistent with the subjects’ genotype in which only the first two M and L genes in the gene array are expressed and was correlated with the estimated spectral separation between photopigments, including in the deuteranomalous trichromats. The L/M cone ratio was highly variable in the color normals. No association was found between cone density and the genotypes and phenotypes investigated, and the cone mosaic arrangement was altered in the dichromats. Conclusions AO-PSOCT is a novel method for assessing color vision phenotype and genotype in single cone cells.
Collapse
Affiliation(s)
- Furu Zhang
- School of Optometry, Indiana University, Bloomington, Indiana, United States.,Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland, United States
| | - Kazuhiro Kurokawa
- School of Optometry, Indiana University, Bloomington, Indiana, United States
| | - Marcel T Bernucci
- School of Optometry, Indiana University, Bloomington, Indiana, United States
| | - Hae Won Jung
- School of Optometry, Indiana University, Bloomington, Indiana, United States
| | - Ayoub Lassoued
- School of Optometry, Indiana University, Bloomington, Indiana, United States
| | - James A Crowell
- School of Optometry, Indiana University, Bloomington, Indiana, United States
| | - Jay Neitz
- Department of Ophthalmology, University of Washington, Seattle, Washington, United States
| | - Maureen Neitz
- Department of Ophthalmology, University of Washington, Seattle, Washington, United States
| | - Donald T Miller
- School of Optometry, Indiana University, Bloomington, Indiana, United States
| |
Collapse
|
49
|
Berkowitz BA, Qian H. OCT imaging of rod mitochondrial respiration in vivo. Exp Biol Med (Maywood) 2021; 246:2151-2158. [PMID: 34024141 DOI: 10.1177/15353702211013799] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
There remains a need for high spatial resolution imaging indices of mitochondrial respiration in the outer retina that probe normal physiology and measure pathogenic and reversible conditions underlying loss of vision. Mitochondria are involved in a critical, but somewhat underappreciated, support system that maintains the health of the outer retina involving stimulus-evoked changes in subretinal space hydration. The subretinal space hydration light-dark response is important because it controls the distribution of vision-critical interphotoreceptor matrix components, including anti-oxidants, pro-survival factors, ions, and metabolites. The underlying signaling pathway controlling subretinal space water management has been worked out over the past 30 years and involves cGMP/mitochondria respiration/pH/RPE water efflux. This signaling pathway has also been shown to be modified by disease-generating conditions, such as hypoxia or oxidative stress. Here, we review recent advances in MRI and commercially available OCT technologies that can measure stimulus-evoked changes in subretinal space water content based on changes in the external limiting membrane-retinal pigment epithelium region. Each step within the above signaling pathway can also be interrogated with FDA-approved pharmaceuticals. A highlight of these studies is the demonstration of first-in-kind in vivo imaging of mitochondria respiration of any cell in the body. Future examinations of subretinal space hydration are expected to be useful for diagnosing threats to sight in aging and disease, and improving the success rate when translating treatments from bench-to-bedside.
Collapse
Affiliation(s)
- Bruce A Berkowitz
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Haohua Qian
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| |
Collapse
|
50
|
Gao S, Li Y, Bissig D, Cohen ED, Podolsky RH, Childers KL, Vernon G, Chen S, Berkowitz BA, Qian H. Functional regulation of an outer retina hyporeflective band on optical coherence tomography images. Sci Rep 2021; 11:10260. [PMID: 33986362 PMCID: PMC8119672 DOI: 10.1038/s41598-021-89599-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 04/27/2021] [Indexed: 12/30/2022] Open
Abstract
Human and animal retinal optical coherence tomography (OCT) images show a hyporeflective band (HB) between the photoreceptor tip and retinal pigment epithelium layers whose mechanisms are unclear. In mice, HB magnitude and the external limiting membrane-retinal pigment epithelium (ELM-RPE) thickness appear to be dependent on light exposure, which is known to alter photoreceptor mitochondria respiration. Here, we test the hypothesis that these two OCT biomarkers are linked to metabolic activity of the retina. Acetazolamide, which acidifies the subretinal space, had no significant impact on HB magnitude but produced ELM-RPE thinning. Mitochondrial stimulation with 2,4-dinitrophenol reduced both HB magnitude and ELM-RPE thickness in parallel, and also reduced F-actin expression in the same retinal region, but without altering ERG responses. For mice strains with relatively lower (C57BL/6J) or higher (129S6/ev) rod mitochondrial efficacy, light-induced changes in HB magnitude and ELM-RPE thickness were correlated. Humans, analyzed from published data captured with a different protocol, showed a similar light–dark change pattern in HB magnitude as in the mice. Our results indicate that mitochondrial respiration underlies changes in HB magnitude upstream of the pH-sensitive ELM-RPE thickness response. These two distinct OCT biomarkers could be useful indices for non-invasively evaluating photoreceptor mitochondrial metabolic activity.
Collapse
Affiliation(s)
- Shasha Gao
- Department of Ophthalmology, the First Affiliated Hospital, Zhengzhou University, Zhengzhou, China.,Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Yichao Li
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - David Bissig
- Department of Neurology, University of California Davis, Sacramento, CA, USA
| | - Ethan D Cohen
- Division of Biomedical Physics, Office of Science and Engineering Labs, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD, USA
| | - Robert H Podolsky
- Beaumont Research Institute, Beaumont Health, Royal Oak, MI, 48073, USA
| | | | - Gregory Vernon
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Sonia Chen
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Bruce A Berkowitz
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, MI, USA
| | - Haohua Qian
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
| |
Collapse
|