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Karaca EE, Işık FD, Hassanpour R, Oztoprak K, Evren Kemer Ö. Machine learning based endothelial cell image analysis of patients undergoing descemet membrane endothelial keratoplasty surgery. BIOMED ENG-BIOMED TE 2024; 0:bmt-2023-0126. [PMID: 38491745 DOI: 10.1515/bmt-2023-0126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 02/28/2024] [Indexed: 03/18/2024]
Abstract
OBJECTIVES In this study, we developed a machine learning approach for postoperative corneal endothelial cell images of patients who underwent Descemet's membrane keratoplasty (DMEK). METHODS An AlexNet model is proposed and validated throughout the study for endothelial cell segmentation and cell location determination. The 506 images of postoperative corneal endothelial cells were analyzed. Endothelial cell detection, segmentation, and determining of its polygonal structure were identified. The proposed model is based on the training of an R-CNN to locate endothelial cells. Next, by determining the ridges separating adjacent cells, the density and hexagonality rates of DMEK patients are calculated. RESULTS The proposed method reached accuracy and F1 score rates of 86.15 % and 0.857, respectively, which indicates that it can reliably replace the manual detection of cells in vivo confocal microscopy (IVCM). The AUC score of 0.764 from the proposed segmentation method suggests a satisfactory outcome. CONCLUSIONS A model focused on segmenting endothelial cells can be employed to assess the health of the endothelium in DMEK patients.
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Affiliation(s)
- Emine Esra Karaca
- Department of Ophthalmology, 536164 University of Health Sciences, Ankara Bilkent City Hospital , Ankara, Türkiye
| | - Feyza Dicle Işık
- Department of Ophthalmology, 536164 University of Health Sciences, Ankara Bilkent City Hospital , Ankara, Türkiye
| | - Reza Hassanpour
- Department of Computer Science, 3647 University of Groningen , Groningen, Netherlands
| | - Kasım Oztoprak
- Department of Computer Engineering, 435784 Konya Food and Agriculture University , Beyşehir Cd., 42080 Meram, Konya, Türkiye
| | - Özlem Evren Kemer
- Department of Ophthalmology, 536164 University of Health Sciences, Ankara Bilkent City Hospital , Ankara, Türkiye
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Han SB, Liu YC, Liu C, Mehta JS. Applications of Imaging Technologies in Fuchs Endothelial Corneal Dystrophy: A Narrative Literature Review. Bioengineering (Basel) 2024; 11:271. [PMID: 38534545 DOI: 10.3390/bioengineering11030271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 03/06/2024] [Accepted: 03/09/2024] [Indexed: 03/28/2024] Open
Abstract
Fuchs endothelial corneal dystrophy (FECD) is a complex genetic disorder characterized by the slow and progressive degeneration of corneal endothelial cells. Thus, it may result in corneal endothelial decompensation and irreversible corneal edema. Moreover, FECD is associated with alterations in all corneal layers, such as thickening of the Descemet membrane, stromal scarring, subepithelial fibrosis, and the formation of epithelial bullae. Hence, anterior segment imaging devices that enable precise measurement of functional and anatomical changes in the cornea are essential for the management of FECD. In this review, the authors will introduce studies on the application of various imaging modalities, such as anterior segment optical coherence tomography, Scheimpflug corneal tomography, specular microscopy, in vitro confocal microscopy, and retroillumination photography, in the diagnosis and monitoring of FECD and discuss the results of these studies. The application of novel technologies, including image processing technology and artificial intelligence, that are expected to further enhance the accuracy, precision, and speed of the imaging technologies will also be discussed.
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Affiliation(s)
- Sang Beom Han
- Saevit Eye Hospital, Goyang 10447, Republic of Korea
| | - Yu-Chi Liu
- Singapore National Eye Centre, Singapore 168751, Singapore
- Singapore Eye Research Institute, Singapore 168751, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore
| | - Chang Liu
- Singapore Eye Research Institute, Singapore 168751, Singapore
| | - Jodhbir S Mehta
- Singapore National Eye Centre, Singapore 168751, Singapore
- Singapore Eye Research Institute, Singapore 168751, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore
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3
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Diabetic Retinopathy: Soluble and Imaging Ocular Biomarkers. J Clin Med 2023; 12:jcm12030912. [PMID: 36769560 PMCID: PMC9917666 DOI: 10.3390/jcm12030912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/18/2023] [Accepted: 01/22/2023] [Indexed: 01/26/2023] Open
Abstract
Diabetic retinopathy (DR), the most common microvascular complication of diabetes mellitus, represents the leading cause of acquired blindness in the working-age population. Due to the potential absence of symptoms in the early stages of the disease, the identification of clinical biomarkers can have a crucial role in the early diagnosis of DR as well as for the detection of prognostic factors. In particular, imaging techniques are fundamental tools for screening, diagnosis, classification, monitoring, treatment planning and prognostic assessment in DR. In this context, the identification of ocular and systemic biomarkers is crucial to facilitate the risk stratification of diabetic patients; moreover, reliable biomarkers could provide prognostic information on disease progression as well as assist in predicting a patient's response to therapy. In this context, this review aimed to provide an updated and comprehensive overview of the soluble and anatomical biomarkers associated with DR.
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Huang YH, Hung JH. In vivo confocal microscopy for eyes with Behçet's disease: a missing piece of the puzzle. Graefes Arch Clin Exp Ophthalmol 2022; 260:3779-3780. [PMID: 36171458 DOI: 10.1007/s00417-022-05848-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 09/17/2022] [Accepted: 09/21/2022] [Indexed: 11/26/2022] Open
Affiliation(s)
- Yi-Hsun Huang
- Department of Ophthalmology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, No.1, University Road, Tainan 701, Taiwan
| | - Jia-Horung Hung
- Department of Ophthalmology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, No.1, University Road, Tainan 701, Taiwan.
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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Qu JH, Qin XR, Peng RM, Xiao GG, Cheng J, Gu SF, Wang HK, Hong J. A Fully Automated Segmentation and Morphometric Parameter Estimation System for Assessing Corneal Endothelial Cell Images. Am J Ophthalmol 2022; 239:142-153. [PMID: 35288075 DOI: 10.1016/j.ajo.2022.02.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 02/21/2022] [Accepted: 02/27/2022] [Indexed: 11/27/2022]
Abstract
PURPOSE To develop a fully automated segmentation and morphometric parameter estimation system for assessing corneal endothelial cells from in vivo confocal microscopy images. DESIGN Artificial intelligence (neural network) study. METHODS First, a fully automated deep learning system for assessing corneal endothelial cells was developed using the development set (from 99 subjects). Second, 184 images (from 97 subjects) were used to construct the testing set to evaluate the clinical validity and usefulness of the automated segmentation and morphometric system. Third, the automatically calculated endothelial cell density (ECD) values, Topcon's cell density, and manually calculated ECD were compared. RESULTS After slit lamp examination, 88 healthy subjects, 2 Fuchs endothelial dystrophy patients, and 7 corneal endotheliitis patients were identified among the 97 subjects in the testing set. The automatedly estimated morphometric parameters for the testing set were an average number of 234 cells, an ECD of 2592 cells/mm2, a coefficient of variation in the cell area of 32.14%, and a percentage of hexagonal cells of 54.16%. Pearson's correlation coefficient between the automated ECD and Topcon's cell density and between the manually calculated ECD and Topcon's cell density was 0.932 (P < .01) and 0.818 (P < .01), respectively. The Bland-Altman plot of Topcon's cell density and the automated ECD yielded 95% limits of agreement between 271.94 and -572.46 (concordance correlation coefficient = 0.9). CONCLUSIONS A fully automated method for segmenting corneal endothelial cells and estimating morphometric parameters using in vivo confocal microscopy images is more efficient and accurate for assessing the normal corneal endothelium.
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Affiliation(s)
- Jing-Hao Qu
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H); Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H)
| | - Xiao-Ran Qin
- Research Center for Brain-inspired Intelligence, Institute of Automation, Chinese Academy of Sciences, Beijing, China (X-R.Q, J.C)
| | - Rong-Mei Peng
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H); Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H)
| | - Ge-Ge Xiao
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H); Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H)
| | - Jian Cheng
- Research Center for Brain-inspired Intelligence, Institute of Automation, Chinese Academy of Sciences, Beijing, China (X-R.Q, J.C)
| | - Shao-Feng Gu
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H); Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H)
| | - Hai-Kun Wang
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H); Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H)
| | - Jing Hong
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H); Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China (J-H.Q, R-M.P, G-G.X, S-F.G, H-K.W, J.H).
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Fu L, Hollick EJ. Long-term Outcomes of Descemet Stripping Endothelial Keratoplasty: Ten-Year Graft Survival and Endothelial Cell Loss. Am J Ophthalmol 2022; 234:215-222. [PMID: 34416181 DOI: 10.1016/j.ajo.2021.08.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 08/05/2021] [Accepted: 08/05/2021] [Indexed: 12/31/2022]
Abstract
PURPOSE To determine 10-year outcomes for graft and endothelial cell survival after Descemet stripping endothelial keratoplasty (DSEK), including risk factors for graft failure. DESIGN Retrospective clinical cohort study. METHODS Three hundred fifty-six consecutive DSEK grafts performed by 10 surgeons using a standardized protocol were analyzed. Primary outcomes were cumulative graft survival and percentage endothelial cell loss (ECL) from 6 months to 10 years; secondary outcomes included risk factors for graft failure, postoperative complications, visual outcomes, and central corneal thickness. RESULTS Indications include Fuchs endothelial dystrophy (n = 209), bullous keratopathy (n = 88), and previous graft failure (n = 39). One hundred and four eyes (29%) had preoperative glaucoma. Cumulative graft survival rates of all eyes at 1, 3, 5, and 10 years were 97%, 90%, 85%, and 79%, respectively. Ten-year graft survival for Fuchs endothelial dystrophy was 92%. Mean ± SD percentage ECL of all grafts was 46.6% ± 17.3% at year 1, 54.9% ± 18.7% at year 3, 59.6% ± 17.4% at year 5, and 73.1% ± 9.7% at year 10. Cox regression identified preoperative glaucoma (hazard ratio [HR]: 8.41; 95% CI, 1.30-54.5; P = .026), including previous glaucoma surgery (HR: 3.63; 95% CI: 1.03-12.74; P = .04) and regrafts (HR: 5.29; 95% CI: 2.02-13.89; P = .001) as significant risk factors for graft failure. CONCLUSIONS At 10 years, DSEK survival rate was 79% for all eyes, including complex grafts, and ECL was 73%. For Fuchs endothelial dystrophy, 10-year graft survival rate was 92%. Despite a mean 10-year endothelial cell count of only 692 cells/mm2, graft survival remained high with good vision. DSEK continues to be a viable treatment option, especially in complex eyes with comorbidity.
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Affiliation(s)
- Lanxing Fu
- Department of Ophthalmology, King's College Hospital NHS Foundation Trust, London, UK
| | - Emma J Hollick
- Department of Ophthalmology, King's College Hospital NHS Foundation Trust, London, UK.
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An automatic approach for cell detection and segmentation of corneal endothelium in specular microscope. Graefes Arch Clin Exp Ophthalmol 2021; 260:1215-1224. [PMID: 34741660 DOI: 10.1007/s00417-021-05483-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 10/18/2021] [Accepted: 10/24/2021] [Indexed: 10/19/2022] Open
Abstract
PURPOSE Specular microscopy is an indispensable tool for clinicians seeking to monitor the corneal endothelium. Automated methods of determining endothelial cell density (ECD) are limited in their ability to analyze images of poor quality. We describe and assess an image processing algorithm to analyze corneal endothelial images. METHODS A set of corneal endothelial images acquired with a Konan CellChek specular microscope was analyzed using three methods: flex-center, Konan Auto Tracer, and the proposed method. In this technique, the algorithm determines the region of interest, filters the image to differentiate cell boundaries from their interiors, and utilizes stochastic watershed segmentation to draw cell boundaries and assess ECD based on the masked region. We compared ECD measured by the algorithm with manual and automated results from the specular microscope. RESULTS We analyzed a total of 303 images manually, using the Auto Tracer, and with the proposed image processing method. Relative to manual analysis across all images, the mean error was 0.04% in the proposed method (p = 0.23 for difference) whereas Auto Tracer demonstrated a bias towards overestimation, with a mean error of 5.7% (p = 2.06× 10-8). The relative mean absolute errors were 6.9% and 7.9%, respectively, for the proposed and Auto Tracer. The average time for analysis of each image using the proposed method was 2.5 s. CONCLUSION We demonstrate a computationally efficient algorithm to analyze corneal endothelial cell density that can be implemented on devices for clinical and research use.
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Doughty MJ, Aakre BM. Further analysis of assessments of the coefficient of variation of corneal endothelial cell areas from specular microscopic images. Clin Exp Optom 2021; 91:438-46. [DOI: 10.1111/j.1444-0938.2008.00281.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Michael J Doughty
- Glasgow‐Caledonian University, Department of Vision Sciences, Scotland and Buskerud University College, Department of Optometry, Kongsberg, Norway
E‐mail:
| | - Bente Monica Aakre
- Glasgow‐Caledonian University, Department of Vision Sciences, Scotland and Buskerud University College, Department of Optometry, Kongsberg, Norway
E‐mail:
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Ong Tone S, Kocaba V, Böhm M, Wylegala A, White TL, Jurkunas UV. Fuchs endothelial corneal dystrophy: The vicious cycle of Fuchs pathogenesis. Prog Retin Eye Res 2021; 80:100863. [PMID: 32438095 PMCID: PMC7648733 DOI: 10.1016/j.preteyeres.2020.100863] [Citation(s) in RCA: 98] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 04/05/2020] [Accepted: 04/10/2020] [Indexed: 12/13/2022]
Abstract
Fuchs endothelial corneal dystrophy (FECD) is the most common primary corneal endothelial dystrophy and the leading indication for corneal transplantation worldwide. FECD is characterized by the progressive decline of corneal endothelial cells (CECs) and the formation of extracellular matrix (ECM) excrescences in Descemet's membrane (DM), called guttae, that lead to corneal edema and loss of vision. FECD typically manifests in the fifth decades of life and has a greater incidence in women. FECD is a complex and heterogeneous genetic disease where interaction between genetic and environmental factors results in cellular apoptosis and aberrant ECM deposition. In this review, we will discuss a complex interplay of genetic, epigenetic, and exogenous factors in inciting oxidative stress, auto(mito)phagy, unfolded protein response, and mitochondrial dysfunction during CEC degeneration. Specifically, we explore the factors that influence cellular fate to undergo apoptosis, senescence, and endothelial-to-mesenchymal transition. These findings will highlight the importance of abnormal CEC-DM interactions in triggering the vicious cycle of FECD pathogenesis. We will also review clinical characteristics, diagnostic tools, and current medical and surgical management options for FECD patients. These new paradigms in FECD pathogenesis present an opportunity to develop novel therapeutics for the treatment of FECD.
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Affiliation(s)
- Stephan Ong Tone
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Viridiana Kocaba
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Myriam Böhm
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Adam Wylegala
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Tomas L White
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Ula V Jurkunas
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States.
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Kristianslund O, Pathak M, Østern AE, Drolsum L. Corneal endothelial cell loss following cataract surgery in patients with pseudoexfoliation syndrome: a 2-year prospective comparative study. Acta Ophthalmol 2020; 98:337-342. [PMID: 31773906 DOI: 10.1111/aos.14314] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 10/31/2019] [Indexed: 12/23/2022]
Abstract
PURPOSE To compare the corneal endothelial cell density (ECD) before and after cataract surgery in patients with and without pseudoexfoliation syndrome (PEX). METHODS In this prospective study, we compared the ECD in 62 PEX patients with 62 patients without PEX (controls). The mean age was 78.3 ± 6.2 years and 77.2 ± 5.9 years, respectively. Patients were examined before and at 6 months, 1 year and 2 years after cataract surgery. The corneal endothelium was examined with confocal microscopy, and the ECD was counted both automatically and semi-manually. Nine patients in the PEX group (15%) and 11 patients in the control group (18%) were lost to follow-up in the 2-year period. Within the PEX and the control groups, we also compared the ECD between patients with and without glaucoma. RESULTS Before surgery, the ECD (semi-manual counting) was 2258 ± 342 cells/mm2 in the PEX group and 2322 ± 321 cells/mm2 in the control group (p = 0.29). There were no significant differences in postoperative ECD between these groups at any visit. After 2 years, the ECD had changed by -679 ± 337 cells/mm2 and -704 ± 484 cells/mm2 , respectively (p = 0.78). The preoperative ECD was lower in eyes with glaucoma compared to eyes without glaucoma, both within the PEX group (p = 0.05) and the control group (p = 0.03). After surgery, there were no differences between eyes with or without glaucoma. CONCLUSION The ECD was not significantly different in PEX eyes compared with control eyes, neither before nor after cataract surgery. However, there seemed to be a lower ECD in eyes with glaucoma before surgery.
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Affiliation(s)
| | - Meeta Pathak
- Institute of Clinical Medicine University of Oslo Oslo Norway
| | | | - Liv Drolsum
- Department of Ophthalmology Oslo University Hospital Oslo Norway
- Institute of Clinical Medicine University of Oslo Oslo Norway
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Toda M, Yukawa H, Yamada J, Ueno M, Kinoshita S, Baba Y, Hamuro J. In Vivo Fluorescence Visualization of Anterior Chamber Injected Human Corneal Endothelial Cells Labeled With Quantum Dots. ACTA ACUST UNITED AC 2019; 60:4008-4020. [DOI: 10.1167/iovs.19-27788] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Munetoyo Toda
- Department of Frontier Medical Science and Technology for Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hiroshi Yukawa
- Institute of Nano-Life-Systems, Institutes of Innovation for Future Society, Nagoya University, Nagoya, Japan
- Nanobio Analytical Chemistry, Biomolecular Chemistry, Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya, Japan
| | - Jun Yamada
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
- Department of Ophthalmology, Meiji University of Integrative Medicine, Nantan, Japan
| | - Morio Ueno
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Shigeru Kinoshita
- Department of Frontier Medical Science and Technology for Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Yoshinobu Baba
- Institute of Nano-Life-Systems, Institutes of Innovation for Future Society, Nagoya University, Nagoya, Japan
- Nanobio Analytical Chemistry, Biomolecular Chemistry, Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya, Japan
- Institute of Innovation for Future Society, Nagoya University, Nagoya, Japan
- Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tokyo, Japan
- College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan, Republic of China
| | - Junji Hamuro
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
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Tone SO, Jurkunas U. Imaging the Corneal Endothelium in Fuchs Corneal Endothelial Dystrophy. Semin Ophthalmol 2019; 34:340-346. [PMID: 31215821 PMCID: PMC6629500 DOI: 10.1080/08820538.2019.1632355] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 06/12/2019] [Indexed: 10/26/2022]
Abstract
Fuchs endothelial corneal dystrophy (FECD) is characterized by the progressive degeneration of the corneal endothelium (CE). The purpose of this article is to review the diagnostic tools available to image and assess the CE in FECD. Slit-lamp biomicroscopy with specular reflection and retroillumination are important techniques to assess the CE. Objective diagnostic tests, such as retroillumination photographic analysis, specular microscopy, in vivo confocal microscopy (IVCM), and anterior segment optical coherence tomography, are valuable tools to evaluate the CE in FECD. Specular microscopy can be performed rapidly without touching the eye but requires a clear cornea with a smooth CE. In contrast, IVCM can image all layers of the cornea, even in advanced FECD. However, IVCM is contact-based and more technically challenging. It is important to select the appropriate objective diagnostic test to image and assess the CE in managing patients with FECD.
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Affiliation(s)
- Stephan Ong Tone
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA USA
| | - Ula Jurkunas
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA USA
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13
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Ong Tone S, Bruha MJ, Böhm M, Prescott C, Jurkunas U. Regional variability in corneal endothelial cell density between guttae and non-guttae areas in Fuchs endothelial corneal dystrophy. Can J Ophthalmol 2019; 54:570-576. [PMID: 31564347 DOI: 10.1016/j.jcjo.2018.12.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/07/2018] [Accepted: 12/31/2018] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To assess the regional variability of corneal endothelial cell density (ECD) between guttae and non-guttae areas in subjects with Fuchs endothelial corneal dystrophy (FECD) using non-contact specular microscopy and confocal microscopy. DESIGN Retrospective chart review from 2009 to 2014 at the Massachusetts Eye and Ear Infirmary. PARTICIPANTS One hundred fifteen eyes of 73 subjects with FECD. METHODS Subjects with FECD underwent same-day specular and confocal microscopy in the same eye. Clinical stage of disease was documented on the day of image acquisition. Regional variability of ECD associated with guttae and non-guttae areas was assessed. Manual endothelial cell counts were performed. RESULTS Thirty-two percent of subjects had high quality endothelial images by both specular and confocal microscopy. Of these subjects, 83% were classified clinically as early-stage FECD. There was a significant association between stage of disease and the ability to obtain high quality specular images (χ2; p = 0.0012). There was no difference in mean ECD derived from specular (1363 ± 594 cells/mm2) or confocal (1391 ± 493 cells/mm2; p = 0.75) images. There was a statistically significant decrease of 31.8 ± 21.7% in mean ECD in areas surrounding guttae (1296 ± 560 cells/mm2) compared to non-guttae areas (1926 ± 674 cells/mm2; p < 0.0001) as determined by confocal microscopy. CONCLUSION These findings support confocal microscopy as an alternative to specular microscopy for evaluating the corneal endothelium of patients with FECD, especially those with advanced disease. Confocal microscopy also revealed regional differences in ECD in guttae and non-guttae areas in patients with FECD.
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Affiliation(s)
- Stephan Ong Tone
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, Mass
| | | | - Myriam Böhm
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, Mass
| | | | - Ula Jurkunas
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, Mass.
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14
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Fully convolutional architecture vs sliding-window CNN for corneal endothelium cell segmentation. BMC Biomed Eng 2019; 1:4. [PMID: 32903308 PMCID: PMC7412678 DOI: 10.1186/s42490-019-0003-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 01/03/2019] [Indexed: 11/23/2022] Open
Abstract
Background Corneal endothelium (CE) images provide valuable clinical information regarding the health state of the cornea. Computation of the clinical morphometric parameters requires the segmentation of endothelial cell images. Current techniques to image the endothelium in vivo deliver low quality images, which makes automatic segmentation a complicated task. Here, we present two convolutional neural networks (CNN) to segment CE images: a global fully convolutional approach based on U-net, and a local sliding-window network (SW-net). We propose to use probabilistic labels instead of binary, we evaluate a preprocessing method to enhance the contrast of images, and we introduce a postprocessing method based on Fourier analysis and watershed to convert the CNN output images into the final cell segmentation. Both methods are applied to 50 images acquired with an SP-1P Topcon specular microscope. Estimates are compared against a manual delineation made by a trained observer. Results U-net (AUC=0.9938) yields slightly sharper, clearer images than SW-net (AUC=0.9921). After postprocessing, U-net obtains a DICE=0.981 and a MHD=0.22 (modified Hausdorff distance), whereas SW-net yields a DICE=0.978 and a MHD=0.30. U-net generates a wrong cell segmentation in only 0.48% of the cells, versus 0.92% for the SW-net. U-net achieves statistically significant better precision and accuracy than both, Topcon and SW-net, for the estimates of three clinical parameters: cell density (ECD), polymegethism (CV), and pleomorphism (HEX). The mean relative error in U-net for the parameters is 0.4% in ECD, 2.8% in CV, and 1.3% in HEX. The computation time to segment an image and estimate the parameters is barely a few seconds. Conclusions Both methods presented here provide a statistically significant improvement over the state of the art. U-net has reached the smallest error rate. We suggest a segmentation refinement based on our previous work to further improve the performance.
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In Vivo Confocal Microscopy Shows Alterations in Nerve Density and Dendritiform Cell Density in Fuchs' Endothelial Corneal Dystrophy. Am J Ophthalmol 2018; 196:136-144. [PMID: 30194928 DOI: 10.1016/j.ajo.2018.08.040] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 08/28/2018] [Accepted: 08/28/2018] [Indexed: 01/14/2023]
Abstract
PURPOSE To evaluate corneal nerve and immune cell alterations in Fuchs' endothelial corneal dystrophy (FECD) and pseudophakic bullous keratopathy (PBK) by laser in vivo confocal microscopy (IVCM) as correlated to corneal sensation and endothelial cell loss. DESIGN Prospective, cross-sectional, controlled study. METHODS Thirty-three eyes with FECD were compared to 13 eyes with PBK and 17 normal age-matched control eyes at a tertiary referral center. FECD was classified into early (without edema) and late stage (with edema). Corneal IVCM and esthesiometry were performed. Corneal nerve and immune dendritiform cell (DC) alterations were evaluated and correlated to clinical parameters. RESULTS FECD and PBK eyes showed significantly (P = .001) diminished total nerve length (11.5 ± 1.3 and 2.9 ± 0.7 mm/mm2) and number (8.8 ± 1.1 and 2.2 ± 0.4 n/frame), compared to controls (23.3 ± 8.1 mm/mm2 and 25.9 ± 1.3 n/frame). Decreased nerves corresponded to diminished sensation in FECD (4.9 ± 0.2 cm; R = 0.32; P = .045), compared to controls (5.9 ± 0.04 cm). Early- and late-stage FECD showed significantly reduced total nerve length (13.1 ± 1.4 and 9.9 ± 1.2 mm/mm2, respectively) and number (8.2 ± 2.5 and 6.5 ± 2.1 n/frame), compared to controls (P < .001). DC density was significantly increased in FECD (57.8 ± 10.4 cells/mm2; P = .01), but not in PBK (47.7 ± 11.6 cells/mm2; P = .60) compared to controls (22.5 ± 4.5 cells/mm2). A subset of early FECD patients (7/22) demonstrated very high DC density (>100/mm2). CONCLUSION IVCM demonstrates profound diminishment of subbasal corneal nerves in early- and late-stage FECD and in PBK, correlating to decreased sensation. Increased DC density in early FECD demonstrates potential subclinical inflammation. The data suggest that reduction in subbasal nerves and increased immune activation may play a role in the pathophysiology of FECD.
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Comparison of Noncontact Specular and Confocal Microscopy for Evaluation of Corneal Endothelium. Eye Contact Lens 2018; 44 Suppl 1:S144-S150. [PMID: 28346276 DOI: 10.1097/icl.0000000000000362] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To compare endothelial cell analysis obtained by noncontact specular and confocal microscopy, using the Konan NSP-9900 and Nidek ConfoScan4 systems, respectively. METHODS Three groups including 70 healthy eyes, 49 eyes with Fuchs endothelial corneal dystrophy (FECD), and 78 eyes with glaucoma were examined with both the Konan NSP-9900 specular microscope and the Nidek ConfocScan4 confocal microscope. Certified graders at the Doheny Image Reading Center compared corneal endothelial images from both instruments side by side to assess image quality. Endothelial cell density (ECD) measurements were calculated and compared using three different modalities: (1) each instrument's fully automated analysis; (2) each instrument's semiautomatic analysis with grader input; and (3) manual grading methods by certified grader. RESULTS All normal eyes yielded gradable endothelial images, and most but not all glaucomatous eyes yielded images with high enough image quality to allow grading. In addition, in corneas with severe FECD, poor image quality precluded ECD grading by specular microscopy in 20 eyes (40.8%) but in only 4 (8.2%) confocal images from the same eyes. For the gradable images, the ECD values obtained using the manual grading method from either device were comparable with no statistically significant difference (P>0.05) between specular and confocal devices. Machine-generated ECD values were significantly different from manual results, measuring greater in all cases with specular microscopy. Machine-generated ECD values from confocal microscopy also differed significantly from manual determinations, but not in a consistent direction. Semiautomatic methods for both instruments obtained clinically acceptable ECD values. CONCLUSIONS Automatic machine-generated ECD measurements differed significantly from manual assessments of corneal endothelium by both specular and confocal microscopy, suggesting that automated results should be used with caution. But ECD values derived manually were comparable between the two devices in both normal and glaucomatous eyes, suggesting that manually graded images from the two instruments can be used interchangeably for reliable ECD measurements. Because of a higher proportion of gradable images, confocal microscopy may be superior to specular microscopy for ECD measurements in FECD.
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Vigueras-Guillen JP, Andrinopoulou ER, Engel A, Lemij HG, van Rooij J, Vermeer KA, van Vliet LJ. Corneal Endothelial Cell Segmentation by Classifier-Driven Merging of Oversegmented Images. IEEE TRANSACTIONS ON MEDICAL IMAGING 2018; 37:2278-2289. [PMID: 29993573 DOI: 10.1109/tmi.2018.2841910] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Corneal endothelium images obtained by in vivo specular microscopy provide important information to assess the health status of the cornea. Estimation of clinical parameters, such as cell density, polymegethism, and pleomorphism, requires accurate cell segmentation. State-of-the-art techniques to automatically segment the endothelium are error-prone when applied to images with low contrast and/or large variation in cell size. Here, we propose an automatic method to segment the endothelium. Starting with an oversegmented image comprised of superpixels obtained from a stochastic watershed segmentation, the proposed method uses intensity and shape information of the superpixels to identify and merge those that constitute a cell, using support vector machines. We evaluated the automatic segmentation on a data set of in vivo specular microscopy images (Topcon SP-1P), obtaining 95.8% correctly merged cells and 2.0% undersegmented cells. We also evaluated the parameter estimation against the results of the vendor's built-in software, obtaining a statistically significant better precision in all parameters and a similar or better accuracy. The parameter estimation was also evaluated on three other data sets from different imaging modalities (confocal microscopy, phase-contrast microscopy, and fluorescence confocal microscopy) and tissue types (ex vivo corneal endothelium and retinal pigment epithelium). In comparison with the estimates of the data sets' authors, we achieved statistically significant better accuracy and precision in all parameters except pleomorphism, where a similar accuracy and precision were obtained.
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Peripheral Endothelial Cell Count Is a Predictor of Disease Severity in Advanced Fuchs Endothelial Corneal Dystrophy. Cornea 2018; 36:1166-1171. [PMID: 28731879 DOI: 10.1097/ico.0000000000001292] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE In advanced Fuchs endothelial corneal dystrophy (FECD), central endothelial changes do not correlate with disease severity. The peripheral endothelial cell count (ECC) has not been studied as a marker of FECD severity. The goal of this study was to determine the relationship between the peripheral ECC and known clinical markers of FECD in advanced cases. METHODS Patients with FECD examined between January 1, 2013, and September 1, 2016, by 1 cornea specialist were identified. Medical records from all previous visits were reviewed to include eyes with high-quality central and peripheral in vivo confocal microscopy images performed on the same day as a clinical evaluation. Endothelial photographs were used to perform manual cell counts centrally and peripherally. Clinical grading of FECD from 1 to 4 was performed at the slit-lamp. RESULTS We identified 154 eyes of 126 patients that met criteria for inclusion. With higher disease grades, central ECC and peripheral ECC decreased, visual acuity worsened, and central corneal thickness (CCT) increased (all P < 0.05). In patients with advanced disease (defined as either grade 3 or 4, CCT >700, or central ECC <350), the peripheral ECC was the best predictor of disease severity and had the highest number of statistically significant correlations with other clinical markers compared with competing variables. CONCLUSIONS In advanced FECD, severity is best determined by the peripheral ECC compared with the central ECC, visual acuity, clinical disease grade, and CCT. The peripheral ECC should be added to the clinical parameters used to evaluate FECD severity.
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Thomasy SM, Cortes DE, Hoehn AL, Calderon AC, Li JY, Murphy CJ. In Vivo Imaging of Corneal Endothelial Dystrophy in Boston Terriers: A Spontaneous, Canine Model for Fuchs' Endothelial Corneal Dystrophy. Invest Ophthalmol Vis Sci 2017; 57:OCT495-503. [PMID: 27454658 PMCID: PMC4968913 DOI: 10.1167/iovs.15-18885] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Purpose Boston Terriers (BTs) have a greater prevalence of corneal endothelial dystrophy (CED), in comparison to other canine breeds. Similar to Fuchs' endothelial corneal dystrophy (FECD), this condition is characterized by endothelial cell degeneration with secondary corneal edema. This study assessed corneal morphology using in vivo confocal microscopy (IVCM) and Fourier-domain optical coherence tomography (FD-OCT) in BTs with and without CED. Methods The corneas of 16 BTs with CED and 15 unaffected, age-matched BTs underwent clinical evaluation and were imaged using IVCM and FD-OCT. A two-sample t-test or Mann-Whitney rank sum test were used to statistically compare parameters between groups. Data are presented as mean ± SD or median (range). Results Mean age did not significantly differ between affected and unaffected dogs at 10.0 ± 2.0 and 10.6 ± 2.4 years, respectively (P = 0.437). Females (69%) were overrepresented among the CED-affected dogs. In CED patients, IVCM demonstrated endothelial polymegathism and pleomorphism. Corneal endothelial density was significantly less (P < 0.001) in dogs with CED (1026 ± 260 cells/mm2) versus age-matched controls (2297 ± 372 cells/mm2). Fourier-domain OCT demonstrated a significant increase (P < 0.01) in central corneal and endothelium-Descemet's complex thickness in dogs with CED versus age-matched controls at 1019 (485–1550) or 536 (464–650) μm and 32 (22–56) or 25 (15–34) μm, respectively. Conclusions Corneal endothelial dystrophy in BTs is a bilateral, adult-onset condition that shares many similarities with FECD. Thus, CED could serve as a spontaneous disease model to study the pathogenesis of and develop novel treatments for FECD.
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Affiliation(s)
- Sara M Thomasy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, California, United States
| | - Dennis E Cortes
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, California, United States
| | - Alyssa L Hoehn
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, California, United States
| | - Allison C Calderon
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, California, United States
| | - Jennifer Y Li
- Department of Ophthalmology & Vision Science, School of Medicine, University of California, Davis, California, United States
| | - Christopher J Murphy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, California, United States 2Department of Ophthalmology & Vision Science, School of Medicine, University of California, Davis, California, Uni
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Abstract
PURPOSE For morphometric analysis of the cell mosaic of corneal endothelium, checking accuracy and precision of instrumentation is a key step. In this study, a standard reference sample is proposed, developed to reproduce the cornea with its shape and the endothelium with its intrinsic variability in the cell size. METHODS A polystyrene bead layer (representing the endothelium) was deposited on a lens (representing the cornea). Bead diameters were 20, 25, and 30 μm (fractions in number 55%, 30%, and 15%, respectively). Bead density and hexagonality were simulated to obtain the expected true values and measured using a slit-lamp endothelial microscope applied to 1) a Takagi 700GL slit lamp at 40× magnification (recommended standard setup) and 2) a Takagi 2ZL slit lamp at 25× magnification. RESULTS The simulation provided the expected bead density 2001 mm and hexagonality 47%. At 40×, density and hexagonality were measured to be 2009 mm (SD 93 mm) and 45% (SD 3%). At 25× on a different slit lamp, the comparison between measured and expected densities provided the factor 1.526 to resize the image and to use the current algorithms of the slit-lamp endothelial microscope for cell recognition. CONCLUSIONS A variable-size polystyrene bead layer on a lens is proposed as a standard sample mimicking the real shape of the cornea and the variability of cell size and cell arrangement of corneal endothelium. The sample is suggested to evaluate accuracy and precision of cell density and hexagonality obtained by different endothelial microscopes, including a slit-lamp endothelial microscope applied to different slit lamps, also at different magnifications.
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Mooren P, Gobin L, Bostan N, Wouters K, Zakaria N, Mathysen DGP, Koppen C. Evaluation of UVA Cytotoxicity for Human Endothelium in an Ex Vivo Corneal Cross-linking Experimental Setting. J Refract Surg 2016; 32:41-6. [PMID: 26812713 DOI: 10.3928/1081597x-20151207-05] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Accepted: 09/22/2015] [Indexed: 11/20/2022]
Abstract
PURPOSE To evaluate endothelial cytotoxicity after exposure of human corneas to ultraviolet-A (UVA) (λ = 365 nm; 5.4 J/cm(2)) in an experimental ex vivo corneal cross-linking setting. METHODS Sixteen pairs of human donor corneas were cut into two pieces. One piece of each cornea was treated with 0.025% riboflavin solution prior to UVA irradiation (5 minutes; 18 mW/cm(2)), whereas the other piece was not irradiated but treated with riboflavin (right eye) or preservation medium (left eye). By irradiating from the endothelial side, the UVA dosage applied to endothelial cells exceeded at least eight times the cytotoxic threshold established in animal models (0.65 J/cm(2)). Endothelial cell counts were performed by two independent investigators after storage (4 to 5 days at 31 °C) and staining (trypan blue, alizarin red). Normality (Q-Q plot; Shapiro-Wilk test) and equivalence (mixed-effects modeling with a 10% equivalence threshold) of the endothelial cell counts of the different groups were evaluated. RESULTS Equivalence of mean endothelial cell density between both groups was observed: 2,237 ± 208 cells/mm(2) in UVA-irradiated pieces and 2,290 ± 281 cells/mm(2) in control pieces (mean difference of 53 ± 240 cells/mm(2) between both groups). CONCLUSIONS Despite direct irradiation of human donor endothelium using the clinical dosage for cross-linking, equivalence in endothelial cell counts was observed between irradiated tissues and controls. Ex vivo human corneal endothelial cells seem to be far more resistant to riboflavin-enhanced UVA irradiation than previously estimated by animal experiments.
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Abstract
PURPOSE A method called EndoKer was recently devised for the morphometric analysis of the cell mosaic of the corneal endothelium. Fully automatic cell recognition is performed on images acquired by a slit-lamp biomicroscope. The aim of this study was to evaluate the accuracy of the EndoKer results. METHODS Analyses were performed on a polystyrene bead layer stratified on a contact lens and in vivo on 30 adults. Accuracy was evaluated by comparing the results of EndoKer with the true values obtained by manual counting of the cells in the same images. EndoKer results were also compared with those obtained with the Tomey EM3000 microscope. RESULTS The accuracy of the results compared with the manual counting on the same images showed a difference of a few percent for the cell density and for hexagonality. This high accuracy derives from (1) the resolution of the slit-lamp images and (2) the improved cell recognition of the fully automatic method. A good agreement was also found between EndoKer and the Tomey EM3000 microscope results. CONCLUSIONS Based on the investigated 30 cases, the slit-lamp biomicroscope may be a viable alternative to dedicated endothelial instruments, providing the additional advantages of a larger investigated area and the possibility to take images of different portions of the cornea. The calibration was performed during the development of the method by using polystyrene beads. The user is not required to perform this calibration. However, such a calibrated sample is suggested for those interested.
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Overestimation of Corneal Endothelial Cell Density in Smaller Frame Sizes in In Vivo Confocal Microscopy. Cornea 2016; 35:363-9. [DOI: 10.1097/ico.0000000000000698] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Laser Scanning In Vivo Confocal Microscopy of Clear Grafts after Penetrating Keratoplasty. BIOMED RESEARCH INTERNATIONAL 2016; 2016:5159746. [PMID: 27034940 PMCID: PMC4789369 DOI: 10.1155/2016/5159746] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 01/29/2016] [Accepted: 02/01/2016] [Indexed: 12/25/2022]
Abstract
PURPOSE To evaluate the changes of keratocytes and dendritic cells in the central clear graft by laser scanning in vivo confocal microscopy after penetrating keratoplasty (PK). METHODS Thirty adult subjects receiving PK at Shandong Eye Institute and with clear grafts and no sign of immune rejection after surgery were recruited into this study, and 10 healthy adults were controls. The keratocytes and dendritic cells in the central graft were evaluated by laser scanning confocal microscopy, as well as epithelium cells, keratocytes, corneal endothelium cells, and corneal nerves (especially subepithelial plexus nerves). RESULTS Median density of subepithelial plexus nerves, keratocyte density in each layer of the stroma, and density of corneal endothelium cells were all lower in clear grafts than in controls. The dendritic cells of five (16.7%) patients were active in Bowman's membrane and stromal membrane of the graft after PK. CONCLUSIONS Activated dendritic cells and Langerhans cells could be detected in some of the clear grafts, which indicated that the subclinical stress of immune reaction took part in the chronic injury of the clear graft after PK, even when there was no clinical rejection episode.
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Recovery of the Corneal Stroma Associated With Rapid Reepithelialization Induced by the Fibronectin-Derived Peptide PHSRN in 2 Cases of Corneal Perforation Due to a Persistent Epithelial Defect. Cornea 2015; 34:1504-7. [DOI: 10.1097/ico.0000000000000592] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Comparison of 4 Specular Microscopes in Healthy Eyes and Eyes With Cornea Guttata or Corneal Grafts. Cornea 2015; 34:381-6. [DOI: 10.1097/ico.0000000000000385] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Kymionis GD, Grentzelos MA, Kankariya VP, Liakopoulos DA, Portaliou DM, Tsoulnaras KI, Karavitaki AE, Pallikaris AI. Safety of high-intensity corneal collagen crosslinking. J Cataract Refract Surg 2015; 40:1337-40. [PMID: 25088634 DOI: 10.1016/j.jcrs.2013.11.041] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 11/13/2013] [Accepted: 11/13/2013] [Indexed: 10/25/2022]
Abstract
PURPOSE To evaluate the safety of a new high-intensity corneal collagen crosslinking (CXL) treatment protocol for keratoconus. SETTING Vardinoyiannion Eye Institute of Crete, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece. DESIGN Prospective interventional case series. METHODS Patients with progressive keratoconus had CXL using a new treatment protocol with 9 mW/cm(2) irradiance for duration of 10 minutes. The rate of reepithelialization, endothelial cell density (ECD), corrected distance visual acuity (CDVA), and steep and flat keratometry (K) values were evaluated preoperatively and 3 months postoperatively. RESULTS Nine patients (10 eyes) were enrolled. No intraoperative or early postoperative complications were observed in any patient. The ECD did not change significantly 3 months postoperatively (P=.169). The CDVA improved from 0.19 logMAR ± 0.20 (SD) preoperatively to 0.10 ± 0.16 logMAR 3 months postoperatively; however, the improvement did not attain significance (P=.141). No eye lost lines of CDVA. The mean steep K readings decreased significantly from 48.04 ± 2.57 diopters (D) preoperatively to 46.51 ± 2.81 D 3 months postoperatively (P=.047); the mean flat K readings did not change significantly postoperatively (P=.285). CONCLUSIONS Corneal collagen crosslinking at 9 mW/cm(2) irradiance for 10 minutes did not cause significant changes in ECD or intraoperative or early postoperative complications. None patient lost a line of CDVA 3 months after the procedure. FINANCIAL DISCLOSURE No author has a financial or proprietary interest in any material or method mentioned.
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Affiliation(s)
- George D Kymionis
- From Vardinoyiannion Eye Institute of Crete (Kymionis, Grentzelos, Kankariya, Liakopoulos, Portaliou, Tsoulnaras, Karavitaki, Pallikaris), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece; the Department of Ophthalmology (Kymionis, Kankariya, Portaliou), Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA.
| | - Michael A Grentzelos
- From Vardinoyiannion Eye Institute of Crete (Kymionis, Grentzelos, Kankariya, Liakopoulos, Portaliou, Tsoulnaras, Karavitaki, Pallikaris), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece; the Department of Ophthalmology (Kymionis, Kankariya, Portaliou), Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Vardhaman P Kankariya
- From Vardinoyiannion Eye Institute of Crete (Kymionis, Grentzelos, Kankariya, Liakopoulos, Portaliou, Tsoulnaras, Karavitaki, Pallikaris), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece; the Department of Ophthalmology (Kymionis, Kankariya, Portaliou), Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Dimitrios A Liakopoulos
- From Vardinoyiannion Eye Institute of Crete (Kymionis, Grentzelos, Kankariya, Liakopoulos, Portaliou, Tsoulnaras, Karavitaki, Pallikaris), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece; the Department of Ophthalmology (Kymionis, Kankariya, Portaliou), Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Dimitra M Portaliou
- From Vardinoyiannion Eye Institute of Crete (Kymionis, Grentzelos, Kankariya, Liakopoulos, Portaliou, Tsoulnaras, Karavitaki, Pallikaris), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece; the Department of Ophthalmology (Kymionis, Kankariya, Portaliou), Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Konstantinos I Tsoulnaras
- From Vardinoyiannion Eye Institute of Crete (Kymionis, Grentzelos, Kankariya, Liakopoulos, Portaliou, Tsoulnaras, Karavitaki, Pallikaris), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece; the Department of Ophthalmology (Kymionis, Kankariya, Portaliou), Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Alexandra E Karavitaki
- From Vardinoyiannion Eye Institute of Crete (Kymionis, Grentzelos, Kankariya, Liakopoulos, Portaliou, Tsoulnaras, Karavitaki, Pallikaris), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece; the Department of Ophthalmology (Kymionis, Kankariya, Portaliou), Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Aristophanis I Pallikaris
- From Vardinoyiannion Eye Institute of Crete (Kymionis, Grentzelos, Kankariya, Liakopoulos, Portaliou, Tsoulnaras, Karavitaki, Pallikaris), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece; the Department of Ophthalmology (Kymionis, Kankariya, Portaliou), Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA
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Corneal assessment technologies: Current status. Surv Ophthalmol 2014; 59:599-614. [DOI: 10.1016/j.survophthal.2014.05.001] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 05/15/2014] [Accepted: 05/20/2014] [Indexed: 11/22/2022]
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Aging and corneal layers: an in vivo corneal confocal microscopy study. Graefes Arch Clin Exp Ophthalmol 2014; 253:267-75. [DOI: 10.1007/s00417-014-2812-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 09/02/2014] [Accepted: 09/22/2014] [Indexed: 12/19/2022] Open
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Corneal nerve alterations in different stages of Fuchs’ endothelial corneal dystrophy: an in vivo confocal microscopy study. Graefes Arch Clin Exp Ophthalmol 2014; 252:1119-26. [DOI: 10.1007/s00417-014-2678-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 02/20/2014] [Accepted: 05/14/2014] [Indexed: 10/25/2022] Open
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McLaren JW, Bachman LA, Kane KM, Patel SV. Objective assessment of the corneal endothelium in Fuchs' endothelial dystrophy. Invest Ophthalmol Vis Sci 2014; 55:1184-90. [PMID: 24508788 DOI: 10.1167/iovs.13-13041] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To develop a standardized method of endothelial cell density (ECD) assessment in Fuchs' endothelial dystrophy that maximizes the sample area and uses the clearest endothelial cells in confocal images. METHODS The corneal endothelium of 51 eyes from 30 patients, with varying degrees of Fuchs' endothelial dystrophy, was examined using confocal microscopy. In two or three distinct images of the central endothelium, local contiguous cell density was determined using a variable frame method. The effective ECD was the product of the local cell density and the fraction of the image that was free of guttae. Two examiners assessed the severity of disease in each eye during slit-lamp examination and assigned a severity grade of 1 to 6. In a second group of 55 eyes with Fuchs' dystrophy from 30 patients, the clinical grade was predicted from the effective ECD and the regression coefficients of the first group and compared to the subjective clinical grade assigned by one examiner. RESULTS The effective ECD decreased linearly with subjective grade (r = -0.93, P < 0.001). The grade predicted from the effective ECD differed from the subjective clinical grade by -0.1 ± 0.8 (mean difference ± standard deviation). CONCLUSIONS The effective ECD in confocal images provides an objective means of assessing the corneal endothelium in Fuchs' dystrophy and might be a useful tool in clinical studies.
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Affiliation(s)
- Jay W McLaren
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota
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Comparison of Manual and Automated Endothelial Cell Density Analysis in Normal Eyes and DSEK Eyes. Cornea 2013; 32:567-73. [PMID: 22893099 DOI: 10.1097/ico.0b013e31825de8fa] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Park YM, Choi BS, Lee JS. Confocal Microscopic Findings of Corneal Tissue in Fuchs' Corneal Endothelial Dystrophy. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2013. [DOI: 10.3341/jkos.2013.54.9.1435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Young Min Park
- Department of Ophthalmology, Pusan National University School of Medicine, Busan, Korea
| | - Beom Seok Choi
- Department of Ophthalmology, Pusan National University School of Medicine, Busan, Korea
| | - Jong Soo Lee
- Department of Ophthalmology, Pusan National University School of Medicine, Busan, Korea
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Cellular and subbasal nerve alterations in early stage Fuchs' endothelial corneal dystrophy: an in vivo confocal microscopy study. Eye (Lond) 2012; 27:42-9. [PMID: 23154490 DOI: 10.1038/eye.2012.220] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
PURPOSE To analyze the morphology and density of corneal epithelial cells, keratocytes, and subbasal nerves, in patients with early stage Fuchs' endothelial corneal dystrophy (FECD) by in vivo confocal microscopy (IVCM). METHODS IVCM (Confoscan 4, Nidek, Inc.) of the central cornea was performed in 30 corneas of 30 patients with early stage FECD and 13 corneas of 13 normal controls. Images were analyzed for morphology and density of the superficial and basal epithelial cells, keratocyte density, endothelial cell density (ECD), as well as subbasal corneal nerve parameters. Central corneal thickness (CCT) was measured in all patients and normals by ultrasound pachymetry. RESULTS The ECD was significantly lower (-45.5%, P<0.001) in FECD patients as compared with controls. Total number of nerves and main nerve trunks were significantly reduced (-46.3%, P<0.001; -39.7%, P<0.001) in patients with FECD. Posterior keratocyte density was significantly higher in FECD patients (P<0.001). Significant inverse correlations were found between CCT and total number of nerves (r=-0.69, P<0.001), CCT and main nerve trunks (-0.47, P=0.016), as well as CCT and total nerve length (r=-0.62, P=0.006). Significant correlation was found between ECD and total number of nerves (r=0.44, P=0.012) as well as between ECD and main nerve trunks (r=0.65, P<0.001). CONCLUSIONS IVCM demonstrates alterations in corneal innervation in patients with early stage FECD, suggesting a potential role of corneal nerves in the pathogenesis of FECD. Additional studies are required to investigate whether subbasal nerve alterations are caused by nonspecific corneal edema, from FECD-induced decrease in ECD, or potentially leading to loss of endothelial cells.
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[Role of in vivo confocal microscopy in irido-corneo-endothelial syndromes]. J Fr Ophtalmol 2012; 35:716.e1-5. [PMID: 22986025 DOI: 10.1016/j.jfo.2011.12.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 12/05/2011] [Accepted: 12/19/2011] [Indexed: 11/22/2022]
Abstract
INTRODUCTION In vivo confocal microscopy (IVCM) is an increasingly utilized tool in studying complex corneal and anterior segment pathologies. We illustrate the role of this imaging technique in the irido-corneo-endothelial (ICE) syndromes through a case report. CASE REPORT A 47-year-old woman presented unilateral decreased vision associated with ocular hypertension and peripheral anterior synechiae. Slit lamp examination of the cornea was unremarkable but IVCM showed pleomorphism and polymegathism of the corneal endothelium and highly reflective nuclei resulting in an epithelial-like cell morphology. This appearance led to the diagnosis of ICE syndrome. DISCUSSION Confocal microscopic findings in ICE syndromes are similar to histopathologic findings. This technique may be for a useful diagnostic adjunct in ICE syndromes by revealing specific characteristics, particularly in difficult diagnostic situations, such as when corneal edema impedes specular microscopy or when the iris fails to demonstrate pathognomonic anomalies.
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Comparison Between Laser Scanning In Vivo Confocal Microscopy and Noncontact Specular Microscopy in Assessing Corneal Endothelial Cell Density and Central Corneal Thickness. Cornea 2011; 30:754-9. [PMID: 21150426 DOI: 10.1097/ico.0b013e3182000c5d] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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In vivo confocal microscopy of the corneal endothelium: comparison of three morphometry methods after corneal transplantation. Eye (Lond) 2011; 25:1130-7. [PMID: 21660067 DOI: 10.1038/eye.2011.121] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
PURPOSE The purpose of this study was to assess the endothelium of corneal grafts by in vivo confocal microscopy (IVCM), and to evaluate an automated endothelial software system in comparison with a manual cell count and planimetry. PATIENTS AND METHODS Overall, 40 corneal grafts (20 deep anterior lamellar keratoplasties (DALKs) and 20 penetrating keratoplasties (PKs)) were assessed by scanning-slit IVCM. The endothelial cell density (ECD) was estimated with the automated and the manual cell count method of the instrument's Nidek Advanced Vision Information System (NAVIS) software. The results were compared with planimetry as the reference method, and the agreement was assessed. RESULTS The mean (±SD) automated ECD was 2278±524 cells/mm(2) (range 1167-3192 cells/mm(2)), whereas the manual cell count method gave significantly lower ECDs with a mean of 1213±677 cells/mm(2) (range 218-2440 cells/mm(2); P<0.001). The manual cell counts were also significantly lower than those by planimetry, with a mean ECD of 1617±813 cells/mm(2) (range 336-2941, P<0.001). Bland-Altman analyses indicated that the limits of agreement (LoA) between the automated and the planimetry method were -671 and +1992 cells/mm(2), whereas they were -1000 and +202 cells/mm(2) when comparing the manual cell counts with planimetry. CONCLUSION Following keratoplasty, the NAVIS automated method is likely to overestimate endothelial cell counts due to oversegmenting of the cell domains. Automated ECDs are substantially higher than those by the manual counting method or planimetry. The differences are considerably larger post-keratoplasty than for normal corneas, and the methods should not be used interchangeably.
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Al-Aqaba M, Alomar T, Lowe J, Dua HS. Corneal nerve aberrations in bullous keratopathy. Am J Ophthalmol 2011; 151:840-849.e1. [PMID: 21310389 DOI: 10.1016/j.ajo.2010.11.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2010] [Revised: 11/11/2010] [Accepted: 11/12/2010] [Indexed: 10/18/2022]
Abstract
PURPOSE To study the corneal nerves in patients with chronic bullous keratopathy. DESIGN Prospective observational case series with histologic evaluation. METHODS We studied 25 eyes of 25 bullous keratopathy patients of different etiologies (17 female, 8 male; mean age, 76.3 years) as well as 6 eyes of 6 normal control subjects (5 male, 1 female; mean age, 38 years). All subjects were scanned by laser scanning confocal microscope. Five corneal buttons obtained following penetrating keratoplasty from 5 of the above patients and 6 normal control corneal buttons were stained as whole mounts with acetylcholinesterase (AChE) method for corneal nerve demonstration and scanned in multiple layers with digital pathology scanning microscope. RESULTS The density, branching pattern, and diameter of sub-basal nerves were significantly lower in corneas with bullous keratopathy compared with normal corneas (density: 4.42 ± 1.91 mm/mm(2) vs 20.05 ± 4.24 mm/mm(2); branching pattern: 36.02% ± 26.57% vs 70.79% ± 10.53%; diameter: 3.07 ± 0.64 μm vs 4.57 ± 1.12 μm). Aberrations such as localized thickenings or excrescences, abnormal twisting, coiling, and looping of the (mid) stromal nerves were observed in the study group both by in vivo confocal microscopy and on histology. CONCLUSIONS Striking alterations in corneal innervation are present in corneas with bullous keratopathy that are unrelated to any specific etiology of bullous keratopathy. This study provides histologic confirmation of novel in vivo confocal microscopy findings related to corneal nerves in bullous keratopathy.
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Módis L, Szalai E, Németh G, Berta A. Evaluation of a recently developed noncontact specular microscope in comparison with conventional pachymetry devices. Eur J Ophthalmol 2010; 20:831-8. [PMID: 20213610 DOI: 10.1177/112067211002000504] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE The study was conducted to assess the central corneal thickness (CCT) of the healthy cornea with a recently developed noncontact specular microscope (EM-3000; Tomey) and compare the results with those measured with a contact specular microscope and an ultrasound pachymeter. Agreement between measurements taken by 2 investigators was also studied. METHODS The right eyes of 41 healthy individuals who had negative history of contact lens wear, ophthalmic disease, or ocular surgery were examined. The CCT was determined sequentially with a noncontact specular microscope, a contact specular microscope (EM-1000; Tomey), and an ultrasound pachymeter (AL-2000; Tomey). Each evaluation with the specular microscopes was performed by 2 independent operators. RESULTS A significant difference was detected in pachymetry measurements among the 3 instruments (p=0.01; analysis of variance). The mean CCT values were lower measured with the ultrasound pachymeter (537+/-30 microm) than the contact endothelial microscope (543+/-37 microm, p=0.17, Student t-test) and the noncontact microscope (549+/-33 microm, p<0.0001) (operator 1). There was no statistically significant difference in CCT measurements between the 2 endothelial microscopes (p=0.19). We found significant correlations (p<0.0001) in thickness measurements between each pair of instruments (r=0.91, noncontact microscopy and ultrasound pachymetry; r=0.74, noncontact and contact microscopy; r=0.72, contact microscopy and ultrasound pachymetry; Spearman rank correlation). CONCLUSIONS The strong correlations among the 3 pachymetry devices suggest that the tested instruments provide reliable measurements; however, they cannot be used interchangeably.
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Affiliation(s)
- László Módis
- Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary.
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Abstract
Fuchs' corneal dystrophy (FCD) is a progressive, hereditary disease of the cornea first described a century ago by the Austrian ophthalmologist Ernst Fuchs. Patients often present in the fifth to sixth decade of life with blurry morning vision that increases in duration as the disease progresses. Primarily a condition of the posterior cornea, characteristic features include the formation of focal excrescences of Descemet membrane termed 'guttae', loss of endothelial cell density and end-stage disease manifested by corneal edema and the formation of epithelial bullae. Recent advances in our understanding of the genetic and pathophysiological mechanisms of the disease, as well as the application of new imaging modalities and less invasive surgical procedures, present new opportunities for improved outcomes among patients with FCD.
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Affiliation(s)
- Allen O Eghrari
- Cataract, Cornea and External Disease Service, Wilmer Eye Institute, 600 North Wolfe Street, 317 Maumenee Building, Baltimore, MD 21287, USA
| | - John D Gottsch
- Cataract, Cornea and External Disease Service, Wilmer Eye Institute, 600 North Wolfe Street, 317 Maumenee Building, Baltimore, MD 21287, USA, Tel.: +1 410 955 7929, Fax: +1 410 614 2816
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Wells AP, Wakely L, Birchall W. In vivo fluorescence mode confocal microscopy of subepithelial tissues in glaucoma filtering blebs. Ophthalmic Surg Lasers Imaging Retina 2010; 41:78-82. [PMID: 20128574 DOI: 10.3928/15428877-20091230-14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/17/2009] [Indexed: 11/20/2022]
Abstract
BACKGROUND AND OBJECTIVE The miniaturization of confocal imaging technology has resulted in the development of a handheld confocal microscope probe capable of fluorescence mode imaging. Findings in the subepithelial tissues of glaucoma filtering blebs using this novel approach for proof of concept are described. PATIENTS AND METHODS A fiberoptic confocal imaging probe using an illumination wavelength of 488 nm was applied to the bleb surface of 11 eyes after topical or subconjunctival administration of sodium fluorescein. The imaging plane was moved to the subepithelial region and multiple images from multiple bleb regions were captured at a resolution of 1,024 x 1,024 pixels per square inch. RESULTS High-quality images of the bleb wall structure, vasculature, and superficial sclera were obtained and demonstrated subcellular detail. Lateral resolution was between 1 and 1.5 microm and axial resolution was approximately 30 microm. Identifiable structures in the failing blebs included vasculature (including individual erythrocytes, pericytes, and vascular endothelium); microcystic structures; and cells within the Tenon's tissue, some of which resembled fibroblasts. CONCLUSION Fluorescence mode imaging of ocular subsurface detail is a viable and promising tool for assessment of wound healing and other processes in trabeculectomy blebs. The ability to image fluorophores creates the possibility of functional imaging.
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Affiliation(s)
- Anthony P Wells
- Ophthalmology Unit, Department of Surgery, Wellington School of Medicine, Mein Street, Wellington 6008, New Zealand
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Traish AS, Colby KA. Approaching cataract surgery in patients with fuchs' endothelial dystrophy. Int Ophthalmol Clin 2010; 50:1-11. [PMID: 20057291 DOI: 10.1097/iio.0b013e3181c5728f] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Affiliation(s)
- Aisha S Traish
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA
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Shenoy R, Khandekar R, Bialasiewicz A, Al Muniri A. Corneal endothelium in patients with diabetes mellitus: a historical cohort study. Eur J Ophthalmol 2009; 19:369-75. [PMID: 19396780 DOI: 10.1177/112067210901900307] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE Retinopathy is the major cause of ocular morbidity in patients with diabetes mellitus. Chronic hyperglycemia spares no organ and can affect the morphology and function of the various corneal layers, compromising its transparency. This study was conducted to associate the status of corneal endothelium to diabetes mellitus (DM) and identify risk factors of compromised corneal endothelium. METHODS A total of 220 eyes of randomly selected patients (110 diabetic and 110 nondiabetic) were subjected to detailed slitlamp and fundus evaluation. Corneal endothelial status was evaluated using the Nidek Confoscan 2. Cell density, percentage polymegathism, and pleomorphism were calculated. The findings in diabetic patients were compared to those without disease. The outcome was correlated to diabetic retinopathy (DR). The effects of hypertension, hyperlipidemia, age, gender, type, duration, glycemic control, and grades of DR was also considered. RESULTS The mean corneal endothelial cell density was -175 cells/mm2 (95% CI -317 to -33 cells/mm2) less in eyes of diabetic patients. The number of endothelial cells with polymegathism was significantly greater among eyes of diabetic patients. There were less corneal endothelial cells with pleomorphism in nondiabetic patients. Polymegathism and pleomorphism of corneal endothelial cells seems to be positively associated with DM type II. Cell density was significantly lower in eyes with DR than those without DR. CONCLUSIONS Corneal endothelium in diabetic patients seems to be compromised. Evaluation of corneal endothelium should be part of protocol for eye care of diabetic patients.
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Affiliation(s)
- Radha Shenoy
- Department of Ophthalmology, SQU Hospital, College of Medicine and Health Sciences, Al Khoud, Oman.
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Morishige N, Takahashi N, Chikamoto N, Nishida T. Quantitative evaluation of corneal epithelial oedema by confocal microscopy. Clin Exp Ophthalmol 2009; 37:249-53. [PMID: 19472533 DOI: 10.1111/j.1442-9071.2009.02020.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Naoyuki Morishige
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan.
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Coupling of HRT II and AS-OCT to evaluate corneal endothelial cell loss and in vivo visualization of the Ahmed glaucoma valve implant. Eye (Lond) 2008; 23:1836-44. [DOI: 10.1038/eye.2008.321] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Doughty MJ, Oblak E. A comparison of two methods for estimating polymegethism in cell areas of the human corneal endothelium. Ophthalmic Physiol Opt 2008; 28:47-56. [PMID: 18201335 DOI: 10.1111/j.1475-1313.2007.00533.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE To compare the outcome measures from two different methods for estimating the coefficient of variation (COV) in cell area for human corneal endothelia. METHODS A single non-contact specular micrograph was obtained from the central region of the corneal endothelium of 100 healthy non-contact lens-wearing white European subjects, aged from 32 to 62 years. The captured image file was either assessed using a machine-based algorithm in which 21 cells were marked and their areas reported (designated as the TOPCON 'centre-dot' method), or by an overlay and semi-automated computer-based image analysis system of the entire image of around 200 cells (designated as the AUTO method). The average cell area values were used to calculate the endothelial cell density (ECD), while the COV was calculated from the standard deviation of the cell area measures. RESULTS The TOPCON and AUTO methods yielded comparable data for average cell area (395 vs 391 microm(2)) and estimated ECD (2566 vs 2575 cells mm(-2)) that were not statistically different (p > or = 0.351), although there was a slight bias between the two methods. However, the mean COV values were very different at 43.5 and 31.4% (p < 0.001). The overestimation of the COV was related to the difference in the largest cell area domain identified by the two methods (p < 0.001, r = > or =0.748). CONCLUSIONS A centre-dot method using a small number of cells generates useful data on cell area and ECD, but it should be used cautiously for estimates of COV.
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Affiliation(s)
- Michael J Doughty
- Department of Vision Sciences, Glasgow Caledonian University, Cowcaddens Road, Glasgow G4 OBA, UK.
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Doughty MJ. Could the coefficient of variation (COV) of the corneal endothelium be overestimated when a centre-dot method is used? Clin Exp Optom 2008; 91:103-10. [PMID: 18045256 DOI: 10.1111/j.1444-0938.2007.00203.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Little has been published on the reliability of estimates of the coefficient of variation (COV) in cell area for human corneal endothelia. The present study compares two methods. METHODS A non-contact specular micrograph (Topcon SP-2000P) was obtained from the central region of the corneal endothelium of 20 healthy myopic white European subjects, aged from 32 to 53 years, half of whom were successful long-term soft contact lens wearers. The captured image file was either assessed using a machine-based algorithm, in which 25 cells in the middle of the image were marked and their areas reported (designated as 'centre-dot' method) or by a manual method, by which all the cells in the image were outlined on very high magnification prints of the endothelia and the cell areas measured by a manual digitiser in stream mode. The average cell area was used to calculate the endothelial cell density (ECD), while the COV was calculated from the standard deviation (SD) of the cell area measures. RESULTS Identical mean cell area values were found (392 microm(2)) with the two methods, a marginally higher ECD estimate (2,594 versus 2,569) with the centre-dot method (p = NS) but a much higher COV with the centre-dot method (43.8 versus 29.0 per cent). This highly statistically significant difference in COV (p < 0.001) was seen in both contact lens wearers and non-contact lens wearers. A Bland-Altman analysis reveals a bias in the centre-dot method, especially for the COV estimates, that appears to be linked to erroneous definition of a single large cell domain on any individual image. CONCLUSIONS A centre-dot method can be reliably used to generate useful data on cell area and ECD but it should be used cautiously for estimates of polymegethism (COV).
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Affiliation(s)
- Michael J Doughty
- Glasgow-Caledonian University, Department of Vision Sciences, Glasgow, Scotland.
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Lee JY, Lee SH, Chung SK, Lee HY. Comparision of Specular Microscopy and Confocal Microscopy for Evaluation of Corneal Endothelium. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2008. [DOI: 10.3341/jkos.2008.49.10.1572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Ja Young Lee
- Department of Ophthalmology, Seoul Adventist Hospital, Seoul, Korea
| | - Seung Hee Lee
- Department of Ophthalmology, Seoul Adventist Hospital, Seoul, Korea
| | - Sung Kun Chung
- Department of Ophthalmology, St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Hae Young Lee
- Department of Ophthalmology, Seoul Adventist Hospital, Seoul, Korea
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Sheng H, Parker EJ, Bullimore MA. An Evaluation of the Confoscan3 for Corneal Endothelial Morphology Analysis. Optom Vis Sci 2007; 84:888-95. [PMID: 17873775 DOI: 10.1097/opx.0b013e3181559c01] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE We evaluated the ConfoScan3 confocal microscope and its associated software that allows automated analysis of the corneal endothelial morphology. METHODS Images were taken on 30 normal subjects and 29 contact lens wearers with the Konan SP-9000 specular microscope and the ConfoScan3. The Konan images were analyzed with the KSS-300 software (center method). The Confoscan3 images were first analyzed with the automated method and then edited manually (semiautomated method). The agreement between methods was evaluated by calculating the difference between pairs of measurements, determining the mean and standard deviation of these differences, and the 95% limits of agreement. RESULTS For normal subjects, all methods gave similar density values. The agreement with the Konan system was slightly better for the semiautomated method than the automated method. The automated method overestimated the degree of polymegethism (p < 0.001) and pleomorphism (p < 0.001). The semiautomated method showed substantial improvement. For contact lens wearers, agreement with the Konan system was poor for both automated and semiautomated methods. The automated method overestimated the degree of pleomorphism (p < 0.001) and the semiautomated method showed only modest improvement (p < 0.1). Both methods overestimated pleomorphism (automated p < 0.001; semiautomated p < 0.025). CONCLUSIONS When using ConfoScan3 to evaluate the corneal endothelium of normal subjects, investigators should manually edit the processed images to achieve results comparable with the Konan system. When evaluating contact lens wearers, values from the ConfoScan3 are not interchangeable with those from the Konan system.
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Affiliation(s)
- Huan Sheng
- The Ohio State University, College of Optometry, Columbus, Ohio, USA.
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Efron N. Contact lens-induced changes in the anterior eye as observed in vivo with the confocal microscope. Prog Retin Eye Res 2007; 26:398-436. [PMID: 17498998 DOI: 10.1016/j.preteyeres.2007.03.003] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The availability of the confocal microscope over the past decade has allowed clinicians and researchers to refine their understanding of the physiological and pathological basis of the ocular response to contact lens wear, and to discover previously unknown phenomena. Mucin balls, which form in the tear layer in patients wearing silicone hydrogel lenses, can penetrate the full thickness of the epithelium, leading to activation of keratocytes in the underlying anterior stroma. Epithelial cell size increases in response to all forms of lens wear, with lenses of higher oxygen transmissibility (Dk/t) interfering least with the normal process of epithelial desquamation. A higher density of Langerhans' cells is observed in the layer of the sub-basal nerve plexus among contact lens wearers, suggesting that contact lens wear may be altering the immune status of the cornea. Dark lines and folds are observed in the oedematous cornea in response to contact lens wear. Mechanical stimulation of the corneal surface, due to the physical presence of a contact lens, and the consequent release of inflammatory mediators, is the likely cause of reduced keratocyte density associated with lens wear. Highly reflective stromal 'microdot deposits' are observed throughout the entire stroma in higher numbers in lens wearers. 'Blebs' in the endothelium have a bright centre surrounded by a dark annular shadow; this appearance is explained with the aid of an optical model. The confocal microscope has considerable clinical utility in diagnosing Acanthamoeba and fungal keratitis. At the limbus, contact lenses can induce structural changes such as increases in basal epithelial cell size. An increased number of rolling leucocytes is observed in limbal vessels in response to low Dk/t lenses. It is concluded that the confocal microscope has considerable utility in contact lens research and practice.
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Affiliation(s)
- Nathan Efron
- Institute of Health and Biomedical Innovation, and School of Optometry, Queensland University of Technology, Corner Musk Avenue and Blamey Street, Kelvin Grove, Queensland 4059, Australia.
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