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Ashourizadeh H, Fakhri M, Hassanpour K, Masoudi A, Jalali S, Roshandel D, Chen FK. Pearls and Pitfalls of Adaptive Optics Ophthalmoscopy in Inherited Retinal Diseases. Diagnostics (Basel) 2023; 13:2413. [PMID: 37510157 PMCID: PMC10377978 DOI: 10.3390/diagnostics13142413] [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: 06/01/2023] [Revised: 07/12/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Adaptive optics (AO) retinal imaging enables individual photoreceptors to be visualized in the clinical setting. AO imaging can be a powerful clinical tool for detecting photoreceptor degeneration at a cellular level that might be overlooked through conventional structural assessments, such as spectral-domain optical coherence tomography (SD-OCT). Therefore, AO imaging has gained significant interest in the study of photoreceptor degeneration, one of the most common causes of inherited blindness. Growing evidence supports that AO imaging may be useful for diagnosing early-stage retinal dystrophy before it becomes apparent on fundus examination or conventional retinal imaging. In addition, serial AO imaging may detect structural disease progression in early-stage disease over a shorter period compared to SD-OCT. Although AO imaging is gaining popularity as a structural endpoint in clinical trials, the results should be interpreted with caution due to several pitfalls, including the lack of standardized imaging and image analysis protocols, frequent ocular comorbidities that affect image quality, and significant interindividual variation of normal values. Herein, we summarize the current state-of-the-art AO imaging and review its potential applications, limitations, and pitfalls in patients with inherited retinal diseases.
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Affiliation(s)
| | - Maryam Fakhri
- Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Sciences, Shahid Beheshti University of Medical Sciences, Tehran 16666, Iran
| | - Kiana Hassanpour
- Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Sciences, Shahid Beheshti University of Medical Sciences, Tehran 16666, Iran
| | - Ali Masoudi
- Stein Eye Institute, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Sattar Jalali
- Department of Physics, Central Tehran Branch, Islamic Azad University, Tehran 19558, Iran
| | - Danial Roshandel
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Nedlands, WA 6009, Australia
- Ocular Tissue Engineering Laboratory, Lions Eye Institute, Nedlands, WA 6009, Australia
| | - Fred K Chen
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Nedlands, WA 6009, Australia
- Ocular Tissue Engineering Laboratory, Lions Eye Institute, Nedlands, WA 6009, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC 3002, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, VIC 3010, Australia
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Heitkotter H, Patterson EJ, Woertz EN, Cava JA, Gaffney M, Adhan I, Tam J, Cooper RF, Carroll J. Extracting spacing-derived estimates of rod density in healthy retinae. BIOMEDICAL OPTICS EXPRESS 2023; 14:1-17. [PMID: 36698662 PMCID: PMC9842010 DOI: 10.1364/boe.473101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 10/11/2022] [Accepted: 11/11/2022] [Indexed: 05/02/2023]
Abstract
Quantification of the rod photoreceptor mosaic using adaptive optics scanning light ophthalmoscopy (AOSLO) remains challenging. Here we demonstrate a method for deriving estimates of rod density and rod:cone ratio based on measures of rod spacing, cone numerosity, and cone inner segment area. Twenty-two AOSLO images with complete rod visualization were used to validate this spacing-derived method for estimating density. The method was then used to estimate rod metrics in an additional 105 images without complete rod visualization. The spacing-derived rod mosaic metrics were comparable to published data from histology. This method could be leveraged to develop large normative databases of rod mosaic metrics, though limitations persist with intergrader variability in assessing cone area and numerosity.
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Affiliation(s)
- Heather Heitkotter
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
- These authors contributed equally to this work
| | - Emily J. Patterson
- UCL Institute of Ophthalmology, University College London, London, UK
- These authors contributed equally to this work
| | - Erica N. Woertz
- John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA
| | - Jenna A. Cava
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Mina Gaffney
- Joint Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, WI, USA
| | - Iniya Adhan
- School of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Johnny Tam
- National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Robert F. Cooper
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
- Joint Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, WI, USA
| | - Joseph Carroll
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
- Joint Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, WI, USA
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Adaptive Optics Imaging to Analyze the Photoreceptor Layer Reconstitution in Acute Syphilitic Posterior Placoid Chorioretinopathy. Life (Basel) 2022; 12:life12091361. [PMID: 36143395 PMCID: PMC9504081 DOI: 10.3390/life12091361] [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] [Received: 07/30/2022] [Revised: 08/19/2022] [Accepted: 08/23/2022] [Indexed: 11/17/2022] Open
Abstract
Acute posterior syphilitic placoid chorioretinopathy (ASPPC) is a rare ocular manifestation of syphilis characterized by outer retinal layers involvement and drop in visual acuity. The current work documents outer retinal layer involvement in this pathology and their reconstitution with treatment by means of adaptive optics (AO). Three eyes of two patients together with four controls eyes were included in the study. Patients underwent optical coherence tomography (OCT) and OCT angiography (OCTA) scan centered on fovea, where vessel density (VD) and vessel perfusion (VP) were calculated. AO images centered on fovea were acquired and cone density (CD) and cone spacing (CS) were measured and compared to control group. Multimodal imaging was performed at presentation, at 10 days, and at 2-month follow-up. All eyes improved in visual acuity, with reconstitution in outer retinal layers at 2-month follow-up. Overall choriocapillary layer VD and VP improved. AO imaging was able to identify outer retinal alterations at presentation and at follow-ups, with improvement in tissue architecture. CD and CS was respectively lower and greater than controls at all follow-ups and improved within patients at the 2-month follow-up. In conclusion, AO was able to document outer retinal alterations in ASPPC at presentation and improvement over the follow-up, representing a tool to study photoreceptor layer involvement in this pathology.
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Wynne N, Heitkotter H, Woertz EN, Cooper RF, Carroll J. Comparison of Cone Mosaic Metrics From Images Acquired With the SPECTRALIS High Magnification Module and Adaptive Optics Scanning Light Ophthalmoscopy. Transl Vis Sci Technol 2022; 11:19. [PMID: 35583887 PMCID: PMC9123519 DOI: 10.1167/tvst.11.5.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 04/18/2022] [Indexed: 12/02/2022] Open
Abstract
Purpose To compare cone mosaic metrics derived from adaptive optics scanning light ophthalmoscopy (AOSLO) images with those derived from Heidelberg Engineering SPECTRALIS High Magnification Module (HMM) images. Methods Participants with contiguous cone mosaics had HMM imaging performed at locations superior and temporal to the fovea. These images were registered and averaged offline and then aligned to split-detection AOSLO images; 200 × 200-µm regions of interest were extracted from both modalities. Cones were semi-automatically identified by two graders to provide estimates of cone density and spacing. Results Thirty participants with contiguous cone mosaics were imaged (10 males, 20 females; age range, 11-67 years). Image quality varied, and 80% of our participants had analyzable HMM images. The intergrader intraclass correlation coefficients for cone metrics were good for both modalities (0.688-0.757 for HMM; 0.805-0.836 for AOSLO). Cone density estimates from HMM images were lower by 2661 cones/mm2 (24.1%) on average compared to AOSLO-derived estimates. Accordingly, HMM estimates of cone spacing were increased on average compared to AOSLO. Conclusions The cone mosaic can be visualized in vivo using the SPECTRALIS HMM, although image quality is variable and imaging is not successful in every individual. Metrics extracted from HMM images can differ from those from AOSLO, although excellent agreement is possible in individuals with excellent optical quality and precise co-registration between modalities. Translational Relevance Emerging non-adaptive optics-based photoreceptor imaging is more clinically accessible than adaptive optics techniques and has potential to expand high-resolution imaging in a clinical environment.
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Affiliation(s)
- Niamh Wynne
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Heather Heitkotter
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Erica N. Woertz
- School of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Robert F. Cooper
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
- Joint Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, WI, USA
| | - Joseph Carroll
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
- Joint Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, WI, USA
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Gerardy M, Yesilirmak N, Legras R, Behar-Cohen F, Bousquet E. CENTRAL SEROUS CHORIORETINOPATHY: High-Resolution Imaging of Asymptomatic Fellow Eyes Using Adaptive Optics Scanning Laser Ophthalmoscopy. Retina 2022; 42:375-380. [PMID: 34620798 PMCID: PMC8765211 DOI: 10.1097/iae.0000000000003311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To investigate cone density in the asymptomatic fellow eye of patients with unilateral central serous chorioretinopathy (CSCR). METHODS Seventeen asymptomatic fellow eyes of patients with unilateral CSCR and 17 eyes of aged-matched and gender-matched healthy controls underwent adaptive optics ophthalmoscopy. Cone density and spacing were assessed at the fovea. Clinical and multimodal imaging findings were also recorded. RESULTS In the CSCR group, the patient mean age was 48.9 ± 9.8 years. The mean (±SD) subfoveal choroidal thickness was 417.8 ± 125.2 µm. The foveal external limiting membrane and ellipsoid zone were intact in all patients. Adaptive optics fundus imaging showed a significant decrease in cone density at 2° of eccentricity nasal and temporal to the fovea in asymptomatic fellow eyes of patients with unilateral CSCR compared with controls (P = 0.001 and P = 0.027, respectively). No statistically significant difference in cone density was found at 4° of eccentricity nasal and temporal to the fovea between both groups. CONCLUSION Asymptomatic fellow eyes of patients with unilateral CSCR showed a reduced density of foveal cones in the absence of a decreased visual acuity and photoreceptor line disruption on optical coherence tomography. These results suggest that the photoreceptors could be damaged independently of the occurrence of a serous retinal detachment.
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Affiliation(s)
- Melvin Gerardy
- Department of Ophthalmology, OphtalmoPôle, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, AP-HP, Université de Paris, Paris, France
| | - Nilufer Yesilirmak
- Department of Ophthalmology, OphtalmoPôle, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, AP-HP, Université de Paris, Paris, France
| | - Richard Legras
- Laboratoire Lumière, Matière et Interfaces, CNRS, ENS Paris-Saclay, Centrale Supelec, Université Paris Saclay, Orsay, France; and
| | - Francine Behar-Cohen
- Department of Ophthalmology, OphtalmoPôle, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, AP-HP, Université de Paris, Paris, France
- Centre de Recherche des Cordeliers, INSERM U1138, Physiopathology of Ccular Diseases: Therapeutic Innovations, Université de Paris, Paris, France.
| | - Elodie Bousquet
- Department of Ophthalmology, OphtalmoPôle, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, AP-HP, Université de Paris, Paris, France
- Centre de Recherche des Cordeliers, INSERM U1138, Physiopathology of Ccular Diseases: Therapeutic Innovations, Université de Paris, Paris, France.
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Evaluation of focus and deep learning methods for automated image grading and factors influencing image quality in adaptive optics ophthalmoscopy. Sci Rep 2021; 11:16641. [PMID: 34404857 PMCID: PMC8371000 DOI: 10.1038/s41598-021-96068-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 07/19/2021] [Indexed: 11/08/2022] Open
Abstract
Adaptive optics flood illumination ophthalmoscopy (AO-FIO) is an established imaging tool in the investigation of retinal diseases. However, the clinical interpretation of AO-FIO images can be challenging due to varied image quality. Therefore, image quality assessment is essential before interpretation. An image assessment tool will also assist further work on improving the image quality, either during acquisition or post processing. In this paper, we describe, validate and compare two automated image quality assessment methods; the energy of Laplacian focus operator (LAPE; not commonly used but easily implemented) and convolutional neural network (CNN; effective but more complex approach). We also evaluate the effects of subject age, axial length, refractive error, fixation stability, disease status and retinal location on AO-FIO image quality. Based on analysis of 10,250 images of 50 × 50 μm size, at 41 retinal locations, from 50 subjects we demonstrate that CNN slightly outperforms LAPE in image quality assessment. CNN achieves accuracy of 89%, whereas LAPE metric achieves 73% and 80% (for a linear regression and random forest multiclass classifier methods, respectively) compared to ground truth. Furthermore, the retinal location, age and disease are factors that can influence the likelihood of poor image quality.
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Cheng H, Ciuffreda KJ, Jiang H, Zhou K, Lin S, Zheng J, Yu X, Vasudevan B, Liang Y. Cone parameters in different vision levels from the adaptive optics imaging. Medicine (Baltimore) 2021; 100:e25618. [PMID: 33879731 PMCID: PMC8078260 DOI: 10.1097/md.0000000000025618] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 04/04/2021] [Indexed: 11/26/2022] Open
Abstract
To investigate the relationship between visual resolution and cone parameters in eyes with different levels of best corrected visual acuity (BCVA).Seventeen eyes of 10 volunteers with BCVA of 20/12.5 or better (group 1) and 16 eyes of 10 volunteers with BCVA of 20/16 (group 2) were investigated in the study. Images of the cone photoreceptors at 1.5° from the fovea were obtained using an adaptive optics (AO) retinal camera. The BCVA was obtained following a subjective refraction using a standardized logMAR visual acuity chart.The mean cone density (29,570.96 ± 2489.94 cells/mm2) at 1.5° from the fovea in group 1 (BCVA ≥ 20/12.5, n = 17) was significantly greater (P < .001) than that (22,963.59 ± 2987.92 cells/mm2) in group 2 (BCVA = 20/16, n = 16). The cone spacing at 1.5° from the fovea in group 1 was 6.45 ± 0.28 μm (mean ± SD), which was significantly smaller (P < .001) than 7.36 ± 0.50 μm (mean ± SD) in group 2. In the stepwise regression analysis, greater angular cone density (odds ratio [OR], 4.48; P = .005) and smaller angular cone spacing (OR, 0.60; P = .007) at 1.5° from the fovea were significantly associated with the better BCVA.The greater cone density and smaller cone spacing at the parafovea were found in eyes with BCVA of 20/12.5 or better, as compared to that in eyes with BCVA of 20/16. Knowledge of cone distribution for different BCVA levels may be beneficial for different clinical conditions.
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Affiliation(s)
- Huanhuan Cheng
- Department of Ophthalmology, the First People's Hospital of Wuhu City, Wuhu
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
| | - Kenneth J. Ciuffreda
- Department of Biological and Vision Sciences, State University of New York College of Optometry
| | - Huilu Jiang
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
- National Clinical Research Center for Ocular Disease, Wenzhou, China
| | - Kun Zhou
- The First Affiliated Hospital of Northwestern University,Xian,China
| | - Sigeng Lin
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
- National Clinical Research Center for Ocular Disease, Wenzhou, China
| | - Jingwei Zheng
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
- National Clinical Research Center for Ocular Disease, Wenzhou, China
| | - Xinping Yu
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
- National Clinical Research Center for Ocular Disease, Wenzhou, China
| | | | - Yuanbo Liang
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
- National Clinical Research Center for Ocular Disease, Wenzhou, China
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Wynne N, Carroll J, Duncan JL. Promises and pitfalls of evaluating photoreceptor-based retinal disease with adaptive optics scanning light ophthalmoscopy (AOSLO). Prog Retin Eye Res 2020; 83:100920. [PMID: 33161127 DOI: 10.1016/j.preteyeres.2020.100920] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 10/28/2020] [Accepted: 10/31/2020] [Indexed: 12/15/2022]
Abstract
Adaptive optics scanning light ophthalmoscopy (AOSLO) allows visualization of the living human retina with exquisite single-cell resolution. This technology has improved our understanding of normal retinal structure and revealed pathophysiological details of a number of retinal diseases. Despite the remarkable capabilities of AOSLO, it has not seen the widespread commercial adoption and mainstream clinical success of other modalities developed in a similar time frame. Nevertheless, continued advancements in AOSLO hardware and software have expanded use to a broader range of patients. Current devices enable imaging of a number of different retinal cell types, with recent improvements in stimulus and detection schemes enabling monitoring of retinal function, microscopic structural changes, and even subcellular activity. This has positioned AOSLO for use in clinical trials, primarily as exploratory outcome measures or biomarkers that can be used to monitor disease progression or therapeutic response. AOSLO metrics could facilitate patient selection for such trials, to refine inclusion criteria or to guide the choice of therapy, depending on the presence, absence, or functional viability of specific cell types. Here we explore the potential of AOSLO retinal imaging by reviewing clinical applications as well as some of the pitfalls and barriers to more widespread clinical adoption.
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Affiliation(s)
- Niamh Wynne
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Joseph Carroll
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Jacque L Duncan
- Department of Ophthalmology, University of California, San Francisco, CA, USA.
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Mendonça LS, Braun PX, Martin SM, Hüther A, Mehta N, Zhao Y, Abu-Qamar O, Konstantinou EK, Regatieri CV, Witkin AJ, Baumal CR, Duker JS, Waheed NK. Repeatability and Reproducibility of Photoreceptor Density Measurement in the Macula Using the Spectralis High Magnification Module. ACTA ACUST UNITED AC 2020; 4:1083-1092. [DOI: 10.1016/j.oret.2020.04.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 04/06/2020] [Accepted: 04/23/2020] [Indexed: 12/20/2022]
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10
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Cone mosaic characteristics in red-green colour deficiency: a comparative study. Can J Ophthalmol 2020; 55:232-238. [DOI: 10.1016/j.jcjo.2019.11.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 10/26/2019] [Accepted: 11/03/2019] [Indexed: 12/21/2022]
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EVALUATION OF PHOTORECEPTORS, RETINAL CAPILLARY PLEXUSES, AND CHORIOCAPILLARIS IN PATIENTS WITH BIRDSHOT CHORIORETINOPATHY. Retina 2020; 40:977-988. [DOI: 10.1097/iae.0000000000002457] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Vukkadala T, Azad S, Kumar V, Kumari A. Adaptive optics imaging in a case of welder's maculopathy. Indian J Ophthalmol 2020; 68:2240-2241. [PMID: 32971662 PMCID: PMC7728048 DOI: 10.4103/ijo.ijo_2289_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Wang Y, Ye J, Shen M, Yao A, Xue A, Fan Y, Huang S, Wang J, Lu F, Shao Y. Photoreceptor Degeneration is Correlated With the Deterioration of Macular Retinal Sensitivity in High Myopia. Invest Ophthalmol Vis Sci 2019; 60:2800-2810. [PMID: 31266057 DOI: 10.1167/iovs.18-26085] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To investigate structural changes in the retinal outer layers and choroid using adaptive optics (AO) and optical coherence tomography (OCT) in eyes with myopia, and to correlate the changes with decreased macular light sensitivity (MLS). Methods This prospective study included 27 subjects with emmetropia and low myopia (EM/LM), 25 with moderate myopia (MM), and 25 with high myopia (HM). Microperimetry was used to quantify MLS in each subject, while AO and OCT images of fundus were analyzed to quantify cone density and regularity and thickness of outer retinal sublayers and choroid. Differences of MLS, cone distribution, and chorioretinal thicknesses were compared among the three groups, and the associations among photoreceptor morphological alterations, MLS, and other parameters were analyzed. Results In HM, the MLS, cone density and regularity, and thicknesses of the myoid and ellipsoid zone (MEZ), Henle fiber layer and outer nuclear layer, interdigitation zone and RPE/Bruch complex, and choroid were lower than in EM/LM. Decreased MLS was correlated with lower cone density and regularity, and thinner MEZ and choroid in the inner region, and with lower cone density, thinner MEZ and choroid, and longer axial length in the outer region. Multivariate regression showed that better MLS was correlated with thicker MEZ in the inner region and with higher cone density in the outer region. Conclusions Altered cone distribution and outer retinal thickness, especially cone density and MEZ thickness, were significantly correlated with decline of MLS in HM, which may help to evaluate and monitor visual impairment in HM.
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Affiliation(s)
- Yuanyuan Wang
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jie Ye
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Meixiao Shen
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Aixia Yao
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Anquan Xue
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yuchen Fan
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Shenghai Huang
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jianhua Wang
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, Miami, Florida, United States
| | - Fan Lu
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yilei Shao
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
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Bottin C, Grieve K, Rossant F, Pedinielli A, Mrejen S, Paques M. DIRECTIONAL VARIABILITY OF FUNDUS REFLECTANCE IN ACUTE MACULAR NEURORETINOPATHY: EVIDENCE FOR A CONTRIBUTION OF THE STILES-CRAWFORD EFFECT. Retin Cases Brief Rep 2018; 12 Suppl 1:S19-S24. [PMID: 29369084 DOI: 10.1097/icb.0000000000000701] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
PURPOSE To document directional reflectivity of fundus lesions in a case of acute macular neuroretinopathy. METHODS Case report. Clinical and imaging data from a patient with acute macular neuroretinopathy were reviewed. Imaging comprised infrared scanning laser ophthalmoscopy, optical coherence tomography and flood-illumination adaptive optics images acquired through different entry pupils in the cardinal directions (approximately 2° eccentricity). RESULTS The patient reported acute bilateral paracentral scotoma revealing dark, wedge-shaped macular plaques which by optical coherence tomography were associated with focal loss of the visibility of the cone outer segment tip and inner/outer segment lines. Comparing scanning laser ophthalmoscopy images taken at different entry points in the pupil showed that macular plaques varied from hyporeflectance to isoreflectance. Cone counts by flood-illumination adaptive optics within plaques and optical coherence tomography features of the cone outer segment tip showed also a strong directional variability, peaking at near-normal values. Within each modality, fusion images showed that directional variability covered most of macular plaques. CONCLUSION The characteristic fundus abnormalities of acute macular neuroretinopathy may show a strong directional variability. Our findings suggest that the Stiles-Crawford effect may be an important factor in signs and symptoms of acute macular neuroretinopathy.
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Affiliation(s)
- Caroline Bottin
- Ophthalmology Department, Quinze-Vingts Hospital, DHU SightMaintain, INSERM-DHOS Clinical Investigation Center 1423, Paris, France
| | - Kate Grieve
- Ophthalmology Department, Quinze-Vingts Hospital, DHU SightMaintain, INSERM-DHOS Clinical Investigation Center 1423, Paris, France
- Université Pierre et Marie Curie-Paris 6, Paris, France
| | | | | | - Sarah Mrejen
- Ophthalmology Department, Quinze-Vingts Hospital, DHU SightMaintain, INSERM-DHOS Clinical Investigation Center 1423, Paris, France
| | - Michel Paques
- Ophthalmology Department, Quinze-Vingts Hospital, DHU SightMaintain, INSERM-DHOS Clinical Investigation Center 1423, Paris, France
- Université Pierre et Marie Curie-Paris 6, Paris, France
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Tumahai P, Moureaux C, Meillat M, Debellemanière G, Flores M, Delbosc B, Saleh M. High-resolution imaging of photoreceptors in healthy human eyes using an adaptive optics retinal camera. Eye (Lond) 2018; 32:1723-1730. [PMID: 29993035 DOI: 10.1038/s41433-018-0140-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 01/21/2018] [Accepted: 02/19/2018] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To determine the effects of age on perifoveal cone density in healthy subjects using adaptive optics. METHODS Healthy subjects of various ages were imaged using an adaptive optics retinal camera (RTX-1® Imagine Eyes, Orsay, France). All patients underwent a comprehensive ophthalmologic examination and retinal imaging using spectral-domain optical coherence tomography (Spectralis®, Heidelberg Engineering, Heidelberg, Germany). Cone density together with cone spacing and cone mosaic packing were measured in the nasal and temporal area 450 µm from the fovea. A multivariate analysis was performed to determine which of the following parameters were related to a decrease in cone density: age, axial length, central macular thickness, and retrofoveal choroidal thickness. RESULTS One hundred and sixty-seven eyes of 101 subjects aged 6-78 years were studied. Perifoveal cone density significantly decreased with age (R2 = 0.17, p<0.01). Inversely, cone spacing increased with age (R2=0.18, p<0.01). There was no change in the cone packing mosaic (p>0.05). The mean coefficient of variation between fellow eyes was 3.9%. Age and axial length were related to a cone density decrease, while choroidal and retinal thicknesses did not affect cone metrics in healthy subjects. CONCLUSIONS A moderate perifoveal cone loss occurs with age. The precise consequences of these findings on visual function should be investigated. In addition to a better understanding of normal retinal anatomy, these results could act as a comparative database for further studies on normal and diseased retinas.
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Affiliation(s)
- P Tumahai
- Ophthalmology Department, University Hospital of Besançon, Besançon, Franche-Comté, France.
| | - C Moureaux
- Ophthalmology Department, University Hospital of Besançon, Besançon, Franche-Comté, France
| | - M Meillat
- Ophthalmology Department, University Hospital of Besançon, Besançon, Franche-Comté, France
| | - G Debellemanière
- Ophthalmology Department, University Hospital of Besançon, Besançon, Franche-Comté, France
| | - M Flores
- Ophthalmology Department, University Hospital of Besançon, Besançon, Franche-Comté, France
| | - B Delbosc
- Ophthalmology Department, University Hospital of Besançon, Besançon, Franche-Comté, France
| | - M Saleh
- Ophthalmology Department, University Hospital of Besançon, Besançon, Franche-Comté, France
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16
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Morgan JIW, Vergilio GK, Hsu J, Dubra A, Cooper RF. The Reliability of Cone Density Measurements in the Presence of Rods. Transl Vis Sci Technol 2018; 7:21. [PMID: 29946495 PMCID: PMC6016505 DOI: 10.1167/tvst.7.3.21] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 05/14/2018] [Indexed: 11/24/2022] Open
Abstract
Purpose Recent advances in adaptive optics scanning light ophthalmoscopy (AOSLO) have enabled visualization of cone inner segments through nonconfocal split-detection, in addition to rod and cone outer segments revealed by confocal reflectance. Here, we examined the interobserver reliability of cone density measurements in both AOSLO imaging modalities. Methods Five normal subjects (nine eyes) were imaged along the horizontal and vertical meridians using a custom AOSLO with confocal and nonconfocal split-detection modalities. The resulting images were montaged using a previously described semiautomatic algorithm. Regions of interest (ROIs) were selected from the confocal montage at 190 μm, and from split-detection and confocal montages at 900 and 1800 μm from the fovea. Four observers (three experts, one naïve) manually identified cone locations in each ROI, and these locations were used to calculate bound densities. Intraclass correlation coefficients and Dice's coefficients were calculated to assess interobserver agreement. Results Interobserver agreement was high in cone-only images (confocal 190 μm: 0.85; split-detection 900 μm: 0.91; split-detection 1800 μm: 0.89), moderate in confocal images at 900 μm (0.68), and poor in confocal images at 1800 μm (0.24). Excluding the naïve observer data substantially increased agreement within confocal images (190 μm: 0.99; 900 μm: 0.80; 1800 μm: 0.68). Conclusions Interobserver measurements of cone density are more reliable in rod-free retinal images. Moreover, when using manual cell identification, it is essential that observers are trained, particularly for confocal AOSLO images. Translational Relevance This study underscores the need for additional reliability studies in eyes containing pathology where identifying cones can be substantially more difficult.
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Affiliation(s)
- Jessica I W Morgan
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Center for Advanced Retinal and Ocular Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Grace K Vergilio
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jessica Hsu
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Alfredo Dubra
- Department of Ophthalmology, Stanford University, Stanford, CA, USA
| | - Robert F Cooper
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Department of Psychology, University of Pennsylvania, Philadelphia, PA, USA
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17
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Davoudi S, Sevgi DD, Yasa C, Laíns I, Ebrahimiadib N, Roohipoor R, Papavasilieou E, Comander J, Sobrin L. High Reliability of Cone Cell Measurements With Adaptive Optics Scanning Laser Ophthalmoscopy in a Simulated Real-Life Clinical Setting. Ophthalmic Surg Lasers Imaging Retina 2018; 49:228-235. [DOI: 10.3928/23258160-20180329-03] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 10/05/2017] [Indexed: 11/20/2022]
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18
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Alonso-Caneiro D, Sampson DM, Chew AL, Collins MJ, Chen FK. Use of focus measure operators for characterization of flood illumination adaptive optics ophthalmoscopy image quality. BIOMEDICAL OPTICS EXPRESS 2018; 9:679-693. [PMID: 29552404 PMCID: PMC5854070 DOI: 10.1364/boe.9.000679] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 01/12/2018] [Accepted: 01/12/2018] [Indexed: 05/06/2023]
Abstract
Adaptive optics flood illumination ophthalmoscopy (AO-FIO) allows imaging of the cone photoreceptor in the living human retina. However, clinical interpretation of the AO-FIO image remains challenging due to suboptimal quality arising from residual uncorrected wavefront aberrations and rapid eye motion. An objective method of assessing image quality is necessary to determine whether an AO-FIO image is suitable for grading and diagnostic purpose. In this work, we explore the use of focus measure operators as a surrogate measure of AO-FIO image quality. A set of operators are tested on data sets acquired at different focal depths and different retinal locations from healthy volunteers. Our results demonstrate differences in focus measure operator performance in quantifying AO-FIO image quality. Further, we discuss the potential application of the selected focus operators in (i) selection of the best quality AO-FIO image from a series of images collected at the same retinal location and (ii) assessment of longitudinal changes in the diseased retina. Focus function could be incorporated into real-time AO-FIO image processing and provide an initial automated quality assessment during image acquisition or reading center grading.
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Affiliation(s)
- David Alonso-Caneiro
- Contact Lens and Visual Optics Laboratory, School of Optometry and Vision Science, Queensland University of Technology, Victoria Park Road, Kelvin Grove QLD 4059, Brisbane, Australia
- Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth, Australia
- Contributed equally to this work
| | - Danuta M. Sampson
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth, Australia
- Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth, Australia
- Contributed equally to this work
| | - Avenell L. Chew
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth, Australia
- Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth, Australia
| | - Michael J. Collins
- Contact Lens and Visual Optics Laboratory, School of Optometry and Vision Science, Queensland University of Technology, Victoria Park Road, Kelvin Grove QLD 4059, Brisbane, Australia
| | - Fred K. Chen
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth, Australia
- Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth, Australia
- Department of Ophthalmology, Royal Perth Hospital, 197 Wellington St., WA 6000, Perth, Australia
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19
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Legras R, Gaudric A, Woog K. Distribution of cone density, spacing and arrangement in adult healthy retinas with adaptive optics flood illumination. PLoS One 2018; 13:e0191141. [PMID: 29338027 PMCID: PMC5770065 DOI: 10.1371/journal.pone.0191141] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 12/28/2017] [Indexed: 11/18/2022] Open
Abstract
The aim of this article is to analyse cone density, spacing and arrangement using an adaptive optics flood illumination retina camera (rtx1™) on a healthy population. Cone density, cone spacing and packing arrangements were measured on the right retinas of 109 subjects at 2°, 3°, 4°, 5° and 6° of eccentricity along 4 meridians. The effects of eccentricity, meridian, axial length, spherical equivalent, gender and age were evaluated. Cone density decreased on average from 28 884 ± 3 692 cones/mm2, at 2° of eccentricity, to 15 843 ± 1 598 cones/mm2 at 6°. A strong inter-individual variation, especially at 2°, was observed. No important difference of cone density was observed between the nasal and temporal meridians or between the superior and inferior meridians. However, the horizontal and vertical meridians differed by around 14% (T-test, p<0.0001). Cone density, expressed in units of area, decreased as a function of axial length (r2 = 0.60), but remained constant (r2 = 0.05) when cone density is expressed in terms of visual angle supporting the hypothesis that the retina is stretched during the elongation of the eyeball. Gender did not modify the cone distribution. Cone density was slightly modified by age but only at 2°. The older group showed a smaller density (7%). Cone spacing increased from 6,49 ± 0,42 μm to 8,72 ± 0,45 μm respectively between 2° and 6° of eccentricity. The mosaic of the retina is mainly triangularly arranged (i.e. cells with 5 to 7 neighbors) from 2° to 6°. Around half of the cells had 6 neighbors.
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Affiliation(s)
- Richard Legras
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, ENS Paris-Saclay, Université Paris-Saclay, Orsay, France
- * E-mail:
| | - Alain Gaudric
- Université Paris Diderot - APHP Hôpital Lariboisière, Paris, France
| | - Kelly Woog
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, ENS Paris-Saclay, Université Paris-Saclay, Orsay, France
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20
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Chew AL, Sampson DM, Kashani I, Chen FK. Agreement in Cone Density Derived from Gaze-Directed Single Images Versus Wide-Field Montage Using Adaptive Optics Flood Illumination Ophthalmoscopy. Transl Vis Sci Technol 2017; 6:9. [PMID: 29285417 PMCID: PMC5744632 DOI: 10.1167/tvst.6.6.9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 10/25/2017] [Indexed: 11/24/2022] Open
Abstract
Purpose We compared cone density measurements derived from the center of gaze-directed single images with reconstructed wide-field montages using the rtx1 adaptive optics (AO) retinal camera. Methods A total of 29 eyes from 29 healthy subjects were imaged with the rtx1 camera. Of 20 overlapping AO images acquired, 12 (at 3.2°, 5°, and 7°) were used for calculating gaze-directed cone densities. Wide-field AO montages were reconstructed and cone densities were measured at the corresponding 12 loci as determined by field projection relative to the foveal center aligned to the foveal dip on optical coherence tomography. Limits of agreement in cone density measurement between single AO images and wide-field AO montages were calculated. Results Cone density measurements failed in 1 or more gaze directions or retinal loci in up to 58% and 33% of the subjects using single AO images or wide-field AO montage, respectively. Although there were no significant overall differences between cone densities derived from single AO images and wide-field AO montages at any of the 12 gazes and locations (P = 0.01-0.65), the limits of agreement between the two methods ranged from as narrow as -2200 to +2600, to as wide as -4200 to +3800 cones/mm2. Conclusions Cone density measurement using the rtx1 AO camera is feasible using both methods. Local variation in image quality and altered visibility of cones after generating montages may contribute to the discrepancies. Translational Relevance Cone densities from single AO images are not interchangeable with wide-field montage derived-measurements.
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Affiliation(s)
- Avenell L Chew
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Western Australia, Australia.,Ocular Tissue Engineering Laboratory, Lions Eye Institute, Perth, Western Australia, Australia
| | - Danuta M Sampson
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Western Australia, Australia.,Ocular Tissue Engineering Laboratory, Lions Eye Institute, Perth, Western Australia, Australia
| | - Irwin Kashani
- Ocular Tissue Engineering Laboratory, Lions Eye Institute, Perth, Western Australia, Australia.,Save Sight Institute, The University of Sydney, Sydney, New South Wales, Australia
| | - Fred K Chen
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Western Australia, Australia.,Ocular Tissue Engineering Laboratory, Lions Eye Institute, Perth, Western Australia, Australia.,Department of Ophthalmology, Royal Perth Hospital, Perth, Western Australia, Australia
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21
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Quantitative analysis of photoreceptor layer reflectivity on en-face optical coherence tomography as an estimator of cone density. Graefes Arch Clin Exp Ophthalmol 2017; 255:2119-2126. [DOI: 10.1007/s00417-017-3761-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 07/12/2017] [Accepted: 07/17/2017] [Indexed: 10/19/2022] Open
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22
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Jacob J, Paques M, Krivosic V, Dupas B, Erginay A, Tadayoni R, Gaudric A. Comparing Parafoveal Cone Photoreceptor Mosaic Metrics in Younger and Older Age Groups Using an Adaptive Optics Retinal Camera. Ophthalmic Surg Lasers Imaging Retina 2017; 48:45-50. [PMID: 28060393 DOI: 10.3928/23258160-20161219-06] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 11/02/2016] [Indexed: 11/20/2022]
Abstract
BACKGROUND AND OBJECTIVE To analyze cone mosaic metrics on adaptive optics (AO) images as a function of retinal eccentricity in two different age groups using a commercial flood illumination AO device. PATIENTS AND METHODS Fifty-three eyes of 28 healthy subjects divided into two age groups were imaged using an AO flood-illumination camera (rtx1; Imagine Eyes, Orsay, France). A 16° × 4° field was obtained horizontally. Cone-packing metrics were determined in five neighboring 50 µm × 50 µm regions. Both retinal (cones/mm2 and µm) and visual (cones/degrees2 and arcmin) units were computed. RESULTS Results for cone mosaic metrics at 2°, 2.5°, 3°, 4°, and 5° eccentricity were compatible with previous AO scanning laser ophthalmoscopy and histology data. No significant difference was observed between the two age groups. CONCLUSIONS The rtx1 camera enabled reproducible measurements of cone-packing metrics across the extrafoveal retina. These findings may contribute to the development of normative data and act as a reference for future research. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:45-50.].
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23
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Zaleska-Żmijewska A, Wawrzyniak ZM, Ulińska M, Szaflik J, Dąbrowska A, Szaflik JP. Human photoreceptor cone density measured with adaptive optics technology (rtx1 device) in healthy eyes: Standardization of measurements. Medicine (Baltimore) 2017; 96:e7300. [PMID: 28640147 PMCID: PMC5484255 DOI: 10.1097/md.0000000000007300] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The anatomic structures of the anterior segment of the eye enable correct reception of stimuli by the retina, which contains receptors that receive light impulses and transmit them to the visual cortex. The aim of this study was to assess the effect of the size of the sampling window in an adaptive optics (AO) flood-illumination retinal camera (rtx1) on cone density measurements in the eyes of healthy individuals and to investigate the differences in cone density and spacing in different quadrants of the retina. Thirty-three subjects with no ophthalmic or systemic disease underwent a detailed ophthalmologic examination. Photographs of retinal fragments 3 degrees from the fovea were taken using the rtx1 AO retinal camera. We used sampling windows with 3 sizes (50 × 50, 100 × 100, and 250 × 250 μm). Cone density, spacing, and shape were determined using AOdetect software. The median (interquartile range) cone density was 19,269 (4964) cones/mm. There were statistically significant differences between measurements taken with the 50/50 and 250/250-m windows. There were no significant differences in the cone spacing results between any of the windows examined, but the measurements differed according to location between the superior and temporal quadrants. The most common cone shape was hexagonal (47.6%) for all window sizes and locations. These findings may help in the development of a normative database for variation in cone density in healthy subjects and to allow the best window to be chosen for obtain the most correct values for eccentricity measurements of 3 degrees. In our study, the optimal sampling window was 100 × 100 μm.
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Affiliation(s)
| | - Zbigniew M. Wawrzyniak
- Faculty of Electronics and Information Technology, Warsaw University of Technology, Warsaw, Poland
| | - Magdalena Ulińska
- Department of Ophthalmology, SPKSO Ophthalmic Hospital, Medical University of Warsaw
| | - Jerzy Szaflik
- Department of Ophthalmology, SPKSO Ophthalmic Hospital, Medical University of Warsaw
| | - Anna Dąbrowska
- Department of Ophthalmology, SPKSO Ophthalmic Hospital, Medical University of Warsaw
| | - Jacek P. Szaflik
- Department of Ophthalmology, SPKSO Ophthalmic Hospital, Medical University of Warsaw
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Litts KM, Cooper RF, Duncan JL, Carroll J. Photoreceptor-Based Biomarkers in AOSLO Retinal Imaging. Invest Ophthalmol Vis Sci 2017; 58:BIO255-BIO267. [PMID: 28873135 PMCID: PMC5584616 DOI: 10.1167/iovs.17-21868] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 07/28/2017] [Indexed: 01/08/2023] Open
Abstract
Improved understanding of the mechanisms underlying inherited retinal degenerations has created the possibility of developing much needed treatments for these relentless, blinding diseases. However, standard clinical indicators of retinal health (such as visual acuity and visual field sensitivity) are insensitive measures of photoreceptor survival. In many retinal degenerations, significant photoreceptor loss must occur before measurable differences in visual function are observed. Thus, there is a recognized need for more sensitive outcome measures to assess therapeutic efficacy as numerous clinical trials are getting underway. Adaptive optics (AO) retinal imaging techniques correct for the monochromatic aberrations of the eye and can be used to provide nearly diffraction-limited images of the retina. Many groups routinely are using AO imaging tools to obtain in vivo images of the rod and cone photoreceptor mosaic, and it now is possible to monitor photoreceptor structure over time with single cell resolution. Highlighting recent work using AO scanning light ophthalmoscopy (AOSLO) across a range of patient populations, we review the development of photoreceptor-based metrics (e.g., density/geometry, reflectivity, and size) as candidate biomarkers. Going forward, there is a need for further development of automated tools and normative databases, with the latter facilitating the comparison of data sets across research groups and devices. Ongoing and future clinical trials for inherited retinal diseases will benefit from the improved resolution and sensitivity that multimodal AO retinal imaging affords to evaluate safety and efficacy of emerging therapies.
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Affiliation(s)
- Katie M. Litts
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Robert F. Cooper
- Department of Psychology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Jacque L. Duncan
- Department of Ophthalmology, University of California, San Francisco, California, United States
| | - Joseph Carroll
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
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25
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Regeneration of Photoreceptor Outer Segments After Scleral Buckling Surgery for Rhegmatogenous Retinal Detachment. Am J Ophthalmol 2017; 177:17-26. [PMID: 28189482 DOI: 10.1016/j.ajo.2017.01.032] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 01/28/2017] [Accepted: 01/30/2017] [Indexed: 11/22/2022]
Abstract
PURPOSE To investigate the regeneration of the cone outer segments in eyes after surgery for fovea-off rhegmatogenous retinal detachment with an adaptive optics (AO) fundus camera and to correlate these findings with the findings of optical coherence tomography (OCT). DESIGN Retrospective, observational case series. METHODS Medical charts of 21 eyes of 21 patients who had undergone surgery for fovea-off rhegmatogenous retinal detachment were retrospectively studied. Cone mosaic images were obtained with an AO fundus camera. Cone packing density at 2 degrees from the fovea within the previously detached area was measured 6 and 12 months after surgery. Retinal thicknesses between the interdigitation zone and the retinal pigment epithelium (IZ-RPE) and between the ellipsoid zone and the retinal pigment epithelium (EZ-RPE) were measured in OCT images. RESULTS Cone density 12 months after surgery was significantly increased from that at 6 months (P = .001), but was still significantly lower than that of normal fellow eyes (P < .001). IZ-RPE and EZ-RPE thickness significantly increased from 6 to 12 months (P = .045, P = .033, respectively), and these values were not significantly different from those of normal fellow eyes. Multivariate analysis showed that cone density at 12 months was significantly associated with IZ-RPE thickness (P = .002), and increases in cone packing density were significantly associated with increases in IZ-RPE thickness (P = .001). CONCLUSIONS Recovery of cone packing density measured by AO was associated with structural recovery of the outer retina observed in OCT, suggesting regeneration of the photoreceptor outer segment after surgery.
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Ueno S, Nakanishi A, Kominami T, Ito Y, Hayashi T, Yoshitake K, Kawamura Y, Tsunoda K, Iwata T, Terasaki H. In vivo imaging of a cone mosaic in a patient with achromatopsia associated with a GNAT2 variant. Jpn J Ophthalmol 2017; 61:92-98. [PMID: 27718025 DOI: 10.1007/s10384-016-0484-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Accepted: 08/30/2016] [Indexed: 11/26/2022]
Abstract
PURPOSE The 2 most common causative genes for achromatopsia (ACHM) are CNGA3 and CNGB3; other genes including GNAT2 account for only a small portion of ACHM cases. The cone mosaics in eyes with CNGA3 and CNGB3 variants are severely disrupted; the cone mosaics in patients with GNAT2-associated ACHM; however, have been reported to show a contiguous pattern in adaptive optics (AO) retinal images. The purpose of this study was to analyze the cone mosaic of another case of GNAT2-associated ACHM. PATIENT AND METHODS The patient was a 17-year-old Japanese boy. Comprehensive ocular examinations including fundus photography, electroretinography (ERGs), optical coherence tomography (OCT), and whole-exome analysis were performed. The cone mosaic was recorded with a flood-illuminated AO fundus camera, and the cone density was compared with those of 10 normal control eyes. RESULTS The patient had the typical phenotype of ACHM, and a novel homozygous variant, c.730_743del, in GNAT2 was identified. The fundus did not show any specific abnormalities, and the OCT images showed the presence of the ellipsoid zone. The AO fundus image showed a clearly defined cone mosaic around the fovea. The cone density at 500 μm from the fovea was reduced by 15-30 % as compared with those of the normal eyes. CONCLUSIONS This is the first description of a Japanese patient with ACHM with a novel GNAT2 variant. The eyes of this patient had a preserved cone structure with loss of function.
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Affiliation(s)
- Shinji Ueno
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, 466-8550, Japan.
| | - Ayami Nakanishi
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Taro Kominami
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Yasuki Ito
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Takaaki Hayashi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Kazutoshi Yoshitake
- National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Yuichi Kawamura
- National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Kazushige Tsunoda
- National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Takeshi Iwata
- National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Hiroko Terasaki
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, 466-8550, Japan
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High-Resolution Imaging of Parafoveal Cones in Different Stages of Diabetic Retinopathy Using Adaptive Optics Fundus Camera. PLoS One 2016; 11:e0152788. [PMID: 27057752 PMCID: PMC4825992 DOI: 10.1371/journal.pone.0152788] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 03/19/2016] [Indexed: 11/19/2022] Open
Abstract
PURPOSE To assess cone density as a marker of early signs of retinopathy in patients with type II diabetes mellitus. METHODS An adaptive optics (AO) retinal camera (rtx1™; Imagine Eyes, Orsay, France) was used to acquire images of parafoveal cones from patients with type II diabetes mellitus with or without retinopathy and from healthy controls with no known systemic or ocular disease. Cone mosaic was captured at 0° and 2°eccentricities along the horizontal and vertical meridians. The density of the parafoveal cones was calculated within 100×100-μm squares located at 500-μm from the foveal center along the orthogonal meridians. Manual corrections of the automated counting were then performed by 2 masked graders. Cone density measurements were evaluated with ANOVA that consisted of one between-subjects factor, stage of retinopathy and the within-subject factors. The ANOVA model included a complex covariance structure to account for correlations between the levels of the within-subject factors. RESULTS Ten healthy participants (20 eyes) and 25 patients (29 eyes) with type II diabetes mellitus were recruited in the study. The mean (± standard deviation [SD]) age of the healthy participants (Control group), patients with diabetes without retinopathy (No DR group), and patients with diabetic retinopathy (DR group) was 55 ± 8, 53 ± 8, and 52 ± 9 years, respectively. The cone density was significantly lower in the moderate nonproliferative diabetic retinopathy (NPDR) and severe NPDR/proliferative DR groups compared to the Control, No DR, and mild NPDR groups (P < 0.05). No correlation was found between cone density and the level of hemoglobin A1c (HbA1c) or the duration of diabetes. CONCLUSIONS The extent of photoreceptor loss on AO imaging may correlate positively with severity of DR in patients with type II diabetes mellitus. Photoreceptor loss may be more pronounced among patients with advanced stages of DR due to higher risk of macular edema and its sequelae.
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Saleh M. [Adaptive optics for ophthalmology]. J Fr Ophtalmol 2016; 39:380-6. [PMID: 27019970 DOI: 10.1016/j.jfo.2015.12.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Revised: 12/08/2015] [Accepted: 12/09/2015] [Indexed: 11/16/2022]
Abstract
Adaptive optics is a technology enhancing the visual performance of an optical system by correcting its optical aberrations. Adaptive optics have already enabled several breakthroughs in the field of visual sciences, such as improvement of visual acuity in normal and diseased eyes beyond physiologic limits, and the correction of presbyopia. Adaptive optics technology also provides high-resolution, in vivo imaging of the retina that may eventually help to detect the onset of retinal conditions at an early stage and provide better assessment of treatment efficacy.
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Affiliation(s)
- M Saleh
- Département d'ophtalmologie, CHU de Besançon, 3, boulevard Fleming, 25030 Besançon, France.
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Lazareva A, Liatsis P, Rauscher FG. Hessian-LoG filtering for enhancement and detection of photoreceptor cells in adaptive optics retinal images. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2016; 33:84-94. [PMID: 26831589 DOI: 10.1364/josaa.33.000084] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Automated analysis of retinal images plays a vital role in the examination, diagnosis, and prognosis of healthy and pathological retinas. Retinal disorders and the associated visual loss can be interpreted via quantitative correlations, based on measurements of photoreceptor loss. Therefore, it is important to develop reliable tools for identification of photoreceptor cells. In this paper, an automated algorithm is proposed, based on the use of the Hessian-Laplacian of Gaussian filter, which allows enhancement and detection of photoreceptor cells. The performance of the proposed technique is evaluated on both synthetic and high-resolution retinal images, in terms of packing density. The results on the synthetic data were compared against ground truth as well as cone counts obtained by the Li and Roorda algorithm. For the synthetic datasets, our method showed an average detection accuracy of 98.8%, compared to 93.9% for the Li and Roorda approach. The packing density estimates calculated on the retinal datasets were validated against manual counts and the results obtained by a proprietary software from Imagine Eyes and the Li and Roorda algorithm. Among the tested methods, the proposed approach showed the closest agreement with manual counting.
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Chew AL, Bukowska D, Chen FK. Structure-function correlation and natural history of accidental juxtafoveal injury from a 250 milliwatt recreational hand-held green laser device. Clin Exp Ophthalmol 2015; 44:201-3. [DOI: 10.1111/ceo.12668] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 09/22/2015] [Accepted: 09/30/2015] [Indexed: 11/27/2022]
Affiliation(s)
- Avenell L Chew
- Lions Eye Institute; Nedlands Western Australia Australia
| | | | - Fred K Chen
- Lions Eye Institute; Nedlands Western Australia Australia
- Royal Perth Hospital; Perth Western Australia Australia
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Bukowska DM, Chew AL, Huynh E, Kashani I, Wan SL, Wan PM, Chen FK. Semi-automated identification of cones in the human retina using circle Hough transform. BIOMEDICAL OPTICS EXPRESS 2015; 6:4676-93. [PMID: 26713186 PMCID: PMC4679246 DOI: 10.1364/boe.6.004676] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 10/30/2015] [Accepted: 10/30/2015] [Indexed: 05/18/2023]
Abstract
A large number of human retinal diseases are characterized by a progressive loss of cones, the photoreceptors critical for visual acuity and color perception. Adaptive Optics (AO) imaging presents a potential method to study these cells in vivo. However, AO imaging in ophthalmology is a relatively new phenomenon and quantitative analysis of these images remains difficult and tedious using manual methods. This paper illustrates a novel semi-automated quantitative technique enabling registration of AO images to macular landmarks, cone counting and its radius quantification at specified distances from the foveal center. The new cone counting approach employs the circle Hough transform (cHT) and is compared to automated counting methods, as well as arbitrated manual cone identification. We explore the impact of varying the circle detection parameter on the validity of cHT cone counting and discuss the potential role of using this algorithm in detecting both cones and rods separately.
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Affiliation(s)
- Danuta M. Bukowska
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth,
Australia
- Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth,
Australia
| | - Avenell L. Chew
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth,
Australia
- Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth,
Australia
| | - Emily Huynh
- Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth,
Australia
| | - Irwin Kashani
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth,
Australia
| | - Sue Ling Wan
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth,
Australia
- Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth,
Australia
| | | | - Fred K Chen
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth,
Australia
- Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth,
Australia
- Department of Ophthalmology, Royal Perth Hospital, 197 Wellington St, WA 6000, Perth,
Australia
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Debellemanière G, Flores M, Tumahai P, Meillat M, Bidaut Garnier M, Delbosc B, Saleh M. Assessment of parafoveal cone density in patients taking hydroxychloroquine in the absence of clinically documented retinal toxicity. Acta Ophthalmol 2015; 93:e534-40. [PMID: 25989823 DOI: 10.1111/aos.12728] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 03/01/2015] [Indexed: 11/27/2022]
Abstract
PURPOSE To measure cone density in patients taking hydroxychloroquine (HCQ), with no clinical evidence of maculopathy. METHODS Patients visiting for HCQ macular toxicity screening in the Besançon University Hospital Ophthalmology Department (France) were studied. They underwent routine examination including spectral-domain optical coherence tomography, fundus autofluorescence and multifocal electroretinogram to detect HCQ-induced retinal toxicity. Cone metrics (density, spacing and percentage of cones with six neighbours) were obtained using an adaptive optics camera (RTX1, Imagine Eyes, Orsay, France). The region of interest corresponded to a 0.3° × 0.3° square placed nasally and temporally at 2° of eccentricity from the fovea. RESULTS Forty eyes of 23 patients were studied. The majority of the patients (21/23) were female. They were aged from 25 to 60 years (mean age ± SD: 40.1 years ± 10). The cumulative dose for HCQ ranged from 24 to 2160 g (777 ± 558 g). None of them displayed HCQ toxicity on screening tests. Bivariate analysis showed moderate cone loss with escalating doses of HCQ (linear regression, r² = 0.23, p = 0.018). Cone spacing also increased with increasing cumulative dose (r² = 0.17, p = 0.008). Cone packing remained unchanged (p > 0.05). Multivariate analysis showed that age and cumulative dose were additive and independent factors of cone dropout. CONCLUSIONS In this pilot study, we observed moderate cone loss as HCQ cumulative doses increased. The early detection of parafoveal cone metric changes may represent the earliest sign of HCQ macular toxicity during screening.
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Affiliation(s)
- Guillaume Debellemanière
- Department of Ophthalmology; Besançon University Hospital; University of Franche-Comté; Besançon France
| | - Mathieu Flores
- Department of Ophthalmology; Besançon University Hospital; University of Franche-Comté; Besançon France
| | - Perle Tumahai
- Department of Ophthalmology; Besançon University Hospital; University of Franche-Comté; Besançon France
| | - Mathieu Meillat
- Department of Ophthalmology; Besançon University Hospital; University of Franche-Comté; Besançon France
| | - Mélanie Bidaut Garnier
- Department of Ophthalmology; Besançon University Hospital; University of Franche-Comté; Besançon France
| | - Bernard Delbosc
- Department of Ophthalmology; Besançon University Hospital; University of Franche-Comté; Besançon France
| | - Maher Saleh
- Department of Ophthalmology; Besançon University Hospital; University of Franche-Comté; Besançon France
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Flores M, Debellemanière G, Bully A, Meillat M, Tumahai P, Delbosc B, Saleh M. Reflectivity of the outer retina on spectral-domain optical coherence tomography as a predictor of photoreceptor cone density. Am J Ophthalmol 2015; 160:588-595.e2. [PMID: 26095264 DOI: 10.1016/j.ajo.2015.06.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 06/08/2015] [Accepted: 06/09/2015] [Indexed: 10/23/2022]
Abstract
PURPOSE To investigate the relationship between outer retinal reflectivity on spectral-domain optical coherence tomography and cone density in the corresponding area. DESIGN Prospective cross-sectional observational study. METHODS In this institutional-based study, 20 eyes of 10 patients presenting maculopathies with various degrees of impairment of the photoreceptor layer (central serous chorioretinopathy, chronic central serous chorioretinopathy, maculopathy associated with hydroxychloroquine, and healthy eyes) were studied. Selection criteria were intended to ensure good image quality. Inner segment ellipsoid band reflectivity, global retinal reflectivity, and relative inner segment ellipsoid reflectivity (defined as the ratio of inner segment ellipsoid band reflectivity on overall retinal reflectivity) were measured on a longitudinal reflectance profile extracted from the spectral-domain optical coherence tomography B-scan. The cone metrics were measured in the same region of interest, located in the perifoveal area, using an adaptive optics retinal camera. RESULTS Inner segment ellipsoid and relative ellipsoid reflectivity were closely correlated with cone density (Pearson r: 0.72 and 0.70, respectively, P < .01). CONCLUSION Outer retinal reflectivity on the transversal optical coherence tomography scan can be correlated to adaptive optics in terms of photoreceptor density. This quantitative approach using optical coherence tomography images could have important implications in the management of maculopathies.
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Metha A, Symons RA. Careful cone counting critical for clinical care. Clin Exp Ophthalmol 2015; 42:807-9. [PMID: 25521579 DOI: 10.1111/ceo.12460] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Andrew Metha
- Department of Optometry and Vision Sciences, The Royal Melbourne Hospital, The University of Melbourne, Parkville, Victoria, Australia
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