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Liu R, Sule AA, Shannon CS, Ravilla T, Taylor H, Rojas-Carabali W, Khanna RC, Mishra C, Sen A, Khatri A, Tan ACS, Sobrin L, Agrawal R. A practical model for effective eye care delivery in Southeast Asian rural communities: A proposal built based on experts' recommendations. Indian J Ophthalmol 2024; 72:S473-S481. [PMID: 38648455 DOI: 10.4103/ijo.ijo_2196_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 01/03/2024] [Indexed: 04/25/2024] Open
Abstract
PURPOSE To evaluate rural community-based eye care models from the perspective of community ophthalmology experts and suggest sustainable technological solutions for enhancing rural eye care delivery. METHODS A semi-structured descriptive survey, using close-ended and open-ended questions, was administered to the experts in community ophthalmology sourced through purposive sampling. The survey was self-administered and was facilitated through online platforms or in-person meetings. Uniform questions were presented to all participants, irrespective of their roles. RESULTS Surveyed participants (n = 22 with 15 from India and 7 from Nepal) in high-volume tertiary eye hospitals faced challenges with resources and rural outreach. Participants had mixed satisfaction with pre-operative screening and theatre resources. Delayed presentations and inexperienced surgeons contributed to the surgery complications. Barriers to rural eye care included resource scarcity, funding disparities, and limited infrastructure. In rural/peri-urban areas 87% of participants agreed with providing primary eye care services, with more than 60% of the experts not in agreement with the makeshift center model of eye care delivery. Key components for an effective eye care model are sustainability, accessibility, affordability, and quality. These can be bolstered through a healthcare management platform and a human-chain supply distribution system. CONCLUSION Tailored interventions are crucial for rural eye care, emphasizing the need for stronger human resources, optimized funding, and community awareness. Addressing challenges pertinent to delayed presentation and surgical training is vital to minimizing complications, especially with advanced cataracts. Enhancements in rural eye care demand a comprehensive approach prioritizing accessibility, affordability, and consistent quality.
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Affiliation(s)
- Renee Liu
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary and Harvard Medical School, Schepens Eye Research Institute, Boston, Massachusetts, USA
| | - Ashita A Sule
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Choo Sheriel Shannon
- Department of Ophthalmology, National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore
| | | | - Hugh Taylor
- Indigenous Eye Health Unit, Melbourne School of Population and Global Health, University of Melbourne, Australia
| | - William Rojas-Carabali
- Department of Ophthalmology, National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore
- Lee Kong Chian School of Medicine, Singapore
| | - Rohit C Khanna
- Allen Foster Community Eye Health Research Centre, Gullapalli Pratibha Rao International Centre for Advancement of Rural Eye Care, L V Prasad Eye Institute, Hyderabad, Telangana, India
| | | | - Alok Sen
- Sadguru Netra Chikatsalaya, Sri Sadguru Seva Sangh Trust, Chitrakoot, Madhya Pradesh, India
| | | | - Anna C S Tan
- Singapore National Eye Centre, Singapore
- Singapore Eye Research Institute, The Academia, Singapore, Singapore
- Department of Ophthalmology and Visual Sciences, Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Lucia Sobrin
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary and Harvard Medical School, Schepens Eye Research Institute, Boston, Massachusetts, USA
| | - Rupesh Agrawal
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Department of Ophthalmology, National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore
- Singapore Eye Research Institute, The Academia, Singapore, Singapore
- Department of Ophthalmology and Visual Sciences, Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- Lee Kong Chian School of Medicine, Singapore
- Moorfields Eye Hospital, NHS Foundation Trust, London, UK
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2
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Peterson CL, Yap CL, Tan TF, Tan LLY, Sim KT, Ong L, Tan ZK, Tan YW, Man R, Fenwick E, Cheung G, Lamoureux E, Tan ACS. Monocular and Binocular Visual Function Assessments and Activities of Daily Living Performance in Age-Related Macular Degeneration. Ophthalmol Retina 2024; 8:32-41. [PMID: 37648064 DOI: 10.1016/j.oret.2023.08.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 08/08/2023] [Accepted: 08/22/2023] [Indexed: 09/01/2023]
Abstract
PURPOSE To evaluate the relationship between specific monocular and binocular visual function (VF) assessments with binocularly performed activities of daily living task tests (ADLTTs) in patients with age-related macular degeneration (AMD) and healthy controls. DESIGN Prospective case-control cohort study. SUBJECTS Thirty-six AMD patients and 36 controls. METHOD Visual field assessments included monocular and binocular best-corrected visual acuity (BCVA), contrast sensitivity (CS), and monocular microperimetry testing for mean macula sensitivity, mean retina sensitivity (MRS), fixation area, and fixation distance from fovea (FDF). Age-related macular degeneration lesion area and sensitivity were measured on OCT and microperimetry, respectively. Participants performed 4 validated ADLTTs with binocular BCVA: (1) reading; (2) item-search; (3) money-counting; and (4) multi-step drink-making tasks. MAIN OUTCOME MEASURES Spearman correlations and multivariate regression analysis, adjusted for age, sex, and potential correlation between the 2 eyes, were used to assess the relationship between monocular and binocular VF assessments, and ADLTT performance in both groups. RESULTS Age-related macular degeneration patients had poorer VF (BCVA, CS, mean macula sensitivity, and MRS) compared with healthy controls. Monocular BCVA in both better- and worse-vision eyes was moderately correlated with the binocular reading speed and money-counting tasks in participants with AMD. In AMD, monocular worse eye CS, MRS, AMD lesion area on OCT, and lesion sensitivity on microperimetry showed moderate correlations to various ADLTTs, such as reading, money-counting, and drink-making. Similar findings were found in our AMD cohort on multivariate regression analysis. Fewer significant correlations were observed for the better-vision eye, whereas no correlations were observed for healthy controls between VF parameters and ADLTTs. In contrast, significant associations were observed between binocular BCVA and CS with binocular ADLTTs (reading and item-search tasks) but not in AMD patients. CONCLUSION Although monocular BCVA remains the most common measure of VF, CS and microperimetry testing also show significant correlations with ADLTTs performance in AMD patients, and should be considered as complimentary VF-outcome measures in both clinical and research settings. Unlike healthy subjects, AMD patients do not rely on binocular VF for ADLTT function, with the worse-vision eye impacting binocular ADLTT function more than the better-vision eye. Therefore, the worse-vision eye should not be neglected during the management of AMD. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Affiliation(s)
- Claire L Peterson
- Singapore National Eye Centre, Singapore; Singapore Eye Research Institute, Singapore; Eye-ACP, Duke-NUS Medical School, Singapore
| | | | - Ting Fang Tan
- Singapore National Eye Centre, Singapore; Singapore Eye Research Institute, Singapore
| | | | | | - Lisa Ong
- Singapore National Eye Centre, Singapore
| | | | - Yan Wen Tan
- Department of Occupational Therapy, Singapore General Hospital, Singapore
| | - Ryan Man
- Singapore National Eye Centre, Singapore; Singapore Eye Research Institute, Singapore; Eye-ACP, Duke-NUS Medical School, Singapore
| | - Eva Fenwick
- Singapore Eye Research Institute, Singapore; Eye-ACP, Duke-NUS Medical School, Singapore
| | - Gemmy Cheung
- Singapore National Eye Centre, Singapore; Singapore Eye Research Institute, Singapore; Eye-ACP, Duke-NUS Medical School, Singapore
| | - Ecosse Lamoureux
- Singapore Eye Research Institute, Singapore; Eye-ACP, Duke-NUS Medical School, Singapore
| | - Anna C S Tan
- Singapore National Eye Centre, Singapore; Singapore Eye Research Institute, Singapore; Eye-ACP, Duke-NUS Medical School, Singapore.
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Fenner BJ, Li H, Gan ATL, Song YS, Tham YC, Jonas JB, Wang YX, Cheng CY, Wong TY, Teo KYC, Tan ACS, Fan Q, Cheung CMG. Genetic Variability of Complement Factor H Has Ethnicity-Specific Associations With Choroidal Thickness. Invest Ophthalmol Vis Sci 2023; 64:10. [PMID: 36749597 PMCID: PMC9919691 DOI: 10.1167/iovs.64.2.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Purpose To identify genetic alleles associated with differences in choroidal thickness (CT) in a population-based multiethnic Asian cohort. Methods A population-based multiethnic Asian cohort without retinal pathology was subjected to spectral-domain OCT (SD-OCT) and genotyping of risk alleles in CFH, VIPR2, ARMS2, and CETP. Subfoveal choroidal thickness (SFCT) values were assessed from SD-OCT, and associations with the risk alleles were determined for each cohort. Results A total of 1045 healthy Asian individuals (550 Chinese, 147 Indians, 348 Malays) were prospectively enrolled in the study. Several CFH alleles (rs800292, rs1061170, and rs1329428) were associated with increased SFCT in Indians (+18.7 to +31.7 µm; P = 0.001-0.038) and marginally associated with decreased SFCT in Malays (-12.7 to -20.6 µm; P = 0.014-0.022). Haplotype analysis of CFH revealed variable associations with SFCT among races, with the H6 haplotype being associated with a 29.08-µm reduction in SFCT in the Chinese cohort (P = 0.02) but a 35.2-µm increase in SFCT in the Indian cohort (P < 0.001). Finally, subfield analysis of the Chinese cohort identified associations between the CFH risk allele rs1061170 and reduced CT in the nasal and superior sectors (-20.2 to -25.8 µm; P = 0.003-0.027). Conclusions CFH variants are variably associated with CT among Asian ethnic groups. This has broad implications for the pathogenesis of common diseases such as age-related macular degeneration and central serous choroidopathy, the pathogenesis of which is associated with CT.
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Affiliation(s)
- Beau J Fenner
- Singapore National Eye Centre, Singapore.,Singapore Eye Research Institute, Singapore
| | | | | | - Young Seok Song
- Singapore Eye Research Institute, Singapore.,Department of Ophthalmology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Yih Chung Tham
- Singapore Eye Research Institute, Singapore.,Centre for Innovation & Precision Eye Health, Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore
| | - Jost B Jonas
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Ya Xing Wang
- Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Ching Yu Cheng
- Singapore Eye Research Institute, Singapore.,Centre for Innovation & Precision Eye Health, Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore
| | - Tien Yin Wong
- School of Medicine, Tsinghua University, Beijing, China
| | - Kelvin Y C Teo
- Singapore National Eye Centre, Singapore.,Singapore Eye Research Institute, Singapore
| | - Anna C S Tan
- Singapore National Eye Centre, Singapore.,Singapore Eye Research Institute, Singapore
| | - Qiao Fan
- Singapore Eye Research Institute, Singapore.,Center for Quantitative Medicine, Duke-NUS Graduate Medical School, Singapore
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Tan TF, Grzybowski A, Ruamviboonsuk P, Tan ACS. Color vision restrictions for medical school admission: a discussion on regulations in ASEAN countries compared to countries across the world. Int J Retina Vitreous 2023; 9:5. [PMID: 36717956 PMCID: PMC9887736 DOI: 10.1186/s40942-023-00441-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Accepted: 01/02/2023] [Indexed: 01/31/2023] Open
Abstract
Color vision deficiency impairs one's ability to perceive and discriminate colors. Color-deficient individuals may face discrimination in various occupations, particularly in medical school admissions. This discussion seeks to compare the existing color vision requirements for entry to medical school in Southeast Asian countries as compared to countries across the world. Following this, we explore the published evidence in this field, to provide recommendations for future guidelines that will maximize the occupational opportunities for color-deficient individuals.
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Affiliation(s)
- Ting Fang Tan
- grid.163555.10000 0000 9486 5048Singapore National Eye Centre, Singapore General Hospital, Singapore, Singapore
| | - Andrzej Grzybowski
- grid.412607.60000 0001 2149 6795Department of Ophthalmology, Institute for Research in Ophthalmology, Foundation for Ophthalmology, University of Warmia and Mazury, Poznan, Poland
| | - Paisan Ruamviboonsuk
- grid.415633.60000 0004 0637 1304Department of Ophthalmology, College of Medicine, Rangsit University, Rajavithi Hospital, Bangkok, Thailand
| | - Anna C. S. Tan
- grid.428397.30000 0004 0385 0924Singapore National Eye Centre, Singapore Eye Research Institute, Duke-NUS, Singapore, Singapore
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5
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Tan ACS, Schwartz R, Anaya D, Chatziralli I, Yuan M, Cicinelli MV, Faes L, Mustapha M, Phasukkijwatana N, Pohlmann D, Reynolds R, Rosenblatt A, Savastano A, Touhami S, Vaezi K, Ventura CV, Vogt D, Ambati J, de Smet MD, Loewenstein A. Are intravitreal injections essential during the COVID-19 pandemic? Global preferred practice patterns and practical recommendations. Int J Retina Vitreous 2022; 8:33. [PMID: 35672810 PMCID: PMC9171474 DOI: 10.1186/s40942-022-00380-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 05/01/2022] [Indexed: 11/12/2022] Open
Abstract
Tertiary outpatient ophthalmology clinics are high-risk environments for COVID-19 transmission, especially retina clinics, where regular follow-up is needed for elderly patients with multiple comorbidities. Intravitreal injection therapy (IVT) for chronic macular diseases, is one of the most common procedures performed, associated with a significant burden of care because of the vigorous treatment regimen associated with multiple investigations. While minimizing the risk of COVID-19 infection transmission is a priority, this must be balanced against the continued provision of sight-saving ophthalmic care to patients at risk of permanent vision loss. This review aims to give evidence-based guidelines on managing IVT during the COVID-19 pandemic in common macular diseases such as age-related macular degeneration, diabetic macula edema and retinal vascular disease and to report on how the COVID-19 pandemic has affected IVT practices worldwide. To illustrate some real-world examples, 18 participants in the International Retina Collaborative, from 15 countries and across four continents, were surveyed regarding pre- and during- COVID-19 pandemic IVT practices in tertiary ophthalmic centers. The majority of centers reported a reduction in the number of appointments to reduce the risk of the spread of COVID-19 with varying changes to their IVT regimen to treat various macula diseases. Due to the constantly evolving nature of the COVID-19 pandemic, and the uncertainty about the normal resumption of health services, we suggest that new solutions for eye healthcare provision, like telemedicine, may be adopted in the future when we consider new long-term adaptations required to cope with the COVID-19 pandemic.
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Affiliation(s)
- A C S Tan
- Singapore National Eye Centre, Singapore, Singapore. .,Singapore Eye Research Institute, Singapore, Singapore. .,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore.
| | - R Schwartz
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - D Anaya
- Department of Retina, Clínica de Oftalmología de Cali, Valle del Cauca, Colombia
| | - I Chatziralli
- 2nd Department of Ophthalmology, National and Kapodistrian University of Athens, Athens, Greece
| | - M Yuan
- Department of Retina, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - M V Cicinelli
- School of Medicine, Vita-Salute San Raffaele University, Milan, Italy.,Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - L Faes
- Moorfields Eye Hospital NHS Foundation Trust, London, UK.,Cantonal Hospital Lucerne, Lucerne, Switzerland
| | - M Mustapha
- Department of Ophthalmology, Universiti Kebangsaan Malaysia, Kulala Lumpur, Malaysia
| | - N Phasukkijwatana
- Department of Ophthalmology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - D Pohlmann
- Charité - Universitätsmedizin Berlin, FreieUiversität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.
| | - R Reynolds
- Department of Ophthalmology, Aneurin Bevan University Health Board, Wales, UK
| | - A Rosenblatt
- Department of Ophthalmology, Tel-Aviv Sourasky Medical Center Tel-Aviv, Israel Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - A Savastano
- Ophthalmology Department, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.,Università Cattolica del Sacro Cuore, Rome, Italy
| | - S Touhami
- Department of Ophthalmology, Reference Center in Rare diseases, DHU Sight Restore, Hôpital Pitié Salpêtrière, Sorbonne Université, 47-83 Boulevard de l'Hôpital, 75013, Paris, France
| | - K Vaezi
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, Canada
| | - C V Ventura
- Department of Ophthalmology, Altino Ventura Foundation (FAV), Recife, Brazil.,Department of Ophthalmology, HOPE Eye Hospital, Recife, Brazil
| | - D Vogt
- Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany
| | - J Ambati
- Center for Advanced Vision Science, Department of Ophthalmology, University of Virginia School of Medicine, Charlottesville, USA
| | - M D de Smet
- Department of Ophthalmology, Leiden University, Leiden, The Netherlands.,MIOS sa, Lausanne, Switzerland
| | - A Loewenstein
- Department of Ophthalmology, Tel-Aviv Sourasky Medical Center Tel-Aviv, Israel Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
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Tan ACS, Jordan-Yu JM, Vyas CH, Gan ATL, Teo KYC, Chan CM, Mathur R, Wong TY, Chakravarthy U, Cheung GCM. OPTICAL COHERENCE TOMOGRAPHY FEATURES OF POLYPOIDAL LESION CLOSURE IN POLYPOIDAL CHOROIDAL VASCULOPATHY TREATED WITH AFLIBERCEPT. Retina 2022; 42:114-122. [PMID: 34412103 DOI: 10.1097/iae.0000000000003285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE To evaluate whether optical coherence tomography (OCT) can determine polypoidal lesion (PL) perfusion in polypoidal choroidal vasculopathy eyes after 12 months of aflibercept monotherapy. Polypoidal lesion perfusion status, assessed by indocyanine green angiography, is an important anatomical outcome in polypoidal choroidal vasculopathy management. METHODS Post hoc data from a prospective randomized, open-label, study in eyes with polypoidal choroidal vasculopathy undergoing monotherapy with aflibercept evaluated PL perfusion status based on indocyanine green angiography (gold standard) and OCT features from baseline to 12 months. RESULTS Individual PLs (110 in total) from 48 eyes (48 patients) showed at 12 months; 57/110 PLs (51.8%) were closed on indocyanine green angiography. At 12 months, eyes with closed PLs were more likely to have the following OCT features: 1) no subretinal fluid (67.1% vs. 32.9%), 2) smaller pigment epithelial detachment height (67.2 [±43.8] vs. 189.2 [±104.9] μm), 3) densely hyperreflective pigment epithelial detachment contents (84.0% vs. 16.0%), 4) an absence of a hyperreflective ring(64.0% vs. 36.0%), and a 5) indistinct overlying retinal pigment epithelial (71.4% vs. 28.6%) (all P < 0.05). The three highest performing OCT features that differentiated perfused from closed PLs were (1), (3), and (4) (area under the receiver operating characteristic curve 0.85, 0.73, and 0.70, respectively). A combination of these three features achieved an area under the receiver operating characteristic curve of 0.90. CONCLUSION Polypoidal lesion closure, an important anatomical treatment outcome in polypoidal choroidal vasculopathy typically defined by indocyanine green angiography, can be accurately detected by specific OCT features.
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Affiliation(s)
- Anna C S Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, National University of Singapore, Singapore; and
| | | | | | - Alfred Tau Liang Gan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
| | - Kelvin Yi Chong Teo
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, National University of Singapore, Singapore; and
| | - ChoI Mun Chan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, National University of Singapore, Singapore; and
| | - Ranjana Mathur
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, National University of Singapore, Singapore; and
| | - Tien Yin Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, National University of Singapore, Singapore; and
| | - Usha Chakravarthy
- Ophthalmology and Vision Sciences, Queen's University Belfast, Belfast, United Kingdom
| | - Gemmy Chui Ming Cheung
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, National University of Singapore, Singapore; and
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7
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Tan W, Yao X, Le TT, Tan ACS, Cheung CY, Chin CWL, Schmetterer L, Chua J. The Application of Optical Coherence Tomography Angiography in Systemic Hypertension: A Meta-Analysis. Front Med (Lausanne) 2021; 8:778330. [PMID: 34859021 PMCID: PMC8630630 DOI: 10.3389/fmed.2021.778330] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 10/20/2021] [Indexed: 01/05/2023] Open
Abstract
Objective: Multiple studies have compared various optical coherence tomography angiography (OCTA) parameters in participants with systemic hypertension vs. controls and have presented discordant findings. We conducted a meta-analysis to pool together data from different studies to generate an overall effect size and find out whether OCTA parameter(s) significantly differed in participants with systemic hypertension as compared to controls. Methods: We conducted a literature search through a search of electronic databases to identify studies before 19 June 2021, which compared OCTA parameters in non-diabetic participants with systemic hypertension vs. controls. If the OCTA parameter had a minimum number of 3 studies that analyzed it, the mean difference between participants with systemic hypertension and controls were analyzed using a random-effects model. Results: We identified 11 eligible studies. At the macula, 9 studies analyzed vessel density at the superficial capillary plexus (SVD), 7 analyzed vessel density at the deep capillary plexus (DVD), and 6 analyzed the area of the superficial foveal avascular zone (FAZ). Participants with systemic hypertension had significantly lower SVD (standardized mean difference [SMD], -0.50 [-0.70, -0.30], P < 0.00001, I 2 = 63%), lower DVD (SMD, -0.38 [-0.64, -0.13], P = 0.004, I 2 = 67%) and larger superficial FAZ (SMD, 0.32 [0.04, 0.61], P = 0.020, I 2 = 77%). Conclusion: The eyes of people with systemic hypertension have robustly lower superficial and deep vascular densities at the macula when compared to control eyes. Our results suggest that OCTA can provide information about pre-clinical microvascular changes from systemic hypertension.
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Affiliation(s)
- Wilson Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore
| | - Xinwen Yao
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
| | - Thu-Thao Le
- National Heart Centre Singapore, National Heart Research Institute Singapore, Singapore, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-National University of Singapore Medical School, Singapore, Singapore
| | - Anna C S Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-National University of Singapore Medical School, Singapore, Singapore
| | - Carol Y Cheung
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Calvin Woon Loong Chin
- National Heart Centre Singapore, National Heart Research Institute Singapore, Singapore, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-National University of Singapore Medical School, Singapore, Singapore
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-National University of Singapore Medical School, Singapore, Singapore.,Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-National University of Singapore Medical School, Singapore, Singapore
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8
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Fenwick EK, Lee EPX, Man REK, Ho KC, Najjar RP, Milea D, Teo KYC, Tan ACS, Lee SY, Yeo IYS, Tan GSW, Mathur R, Wong TY, Cheung CMG, Lamoureux EL. Identifying the content for an item bank and computerized adaptive testing system to measure the impact of age-related macular degeneration on health-related quality of life. Qual Life Res 2021; 31:1237-1246. [PMID: 34562188 DOI: 10.1007/s11136-021-02989-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2021] [Indexed: 11/27/2022]
Abstract
PURPOSE We are developing an age-related macular degeneration (AMD) health-related quality of life (HRQoL) item bank, applicable to Western and Asian populations. We report primarily on content generation and refinement, but also compare the HRQoL issues reported in our study with Western studies and current AMD-HRQoL questionnaires. METHODS In this cross-sectional, qualitative study of AMD patients attending the Singapore National Eye Centre (May-December 2019), items/domains were generated from: (1) AMD-specific questionnaires; (2) published articles; (3) focus groups/semi-structured interviews with AMD patients (n = 27); and (4) written feedback from retinal experts. Following thematic analysis, items were systematically refined to a minimally representative set and pre-tested using cognitive interviews with 16 AMD patients. RESULTS Of the 27 patients (mean ± standard deviation age 67.9 ± 7.0; 59.2% male), 18 (66.7%), two (7.4%), and seven (25.9%) had no, early-intermediate, and late/advanced AMD (better eye), respectively. Whilst some HRQoL issues, e.g. activity limitation, mobility, lighting, and concerns were similarly reported by Western patients and covered by other questionnaires, others like anxiety about intravitreal injections, work tasks, and financial dependency were novel. Overall, 462 items within seven independent HRQoL domains were identified: Activity limitation, Lighting, Mobility, Emotional, Concerns, AMD management, and Work. Following item refinement, items were reduced to 219, with 31 items undergoing amendment. CONCLUSION Our 7-domain, 219-item AMD-specific HRQoL instrument will undergo psychometric testing and calibration for computerized adaptive testing. The future instrument will enable users to precisely, rapidly, and comprehensively quantify the HRQoL impact of AMD and associated treatments, with item coverage relevant across several populations.
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Affiliation(s)
- Eva K Fenwick
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore.,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Ester P X Lee
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore
| | - Ryan E K Man
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore.,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Kam Chun Ho
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore.,UNSW Sydney, Sydney, Australia
| | - Raymond P Najjar
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore.,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Dan Milea
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore
| | - Kelvin Y C Teo
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore.,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Anna C S Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore.,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Shu Yen Lee
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore.,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Ian Yew San Yeo
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore.,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Gavin S W Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore.,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Ranjana Mathur
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore.,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Tien Yin Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore.,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Chui Ming Gemmy Cheung
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore
| | - Ecosse L Lamoureux
- Singapore Eye Research Institute, Singapore National Eye Centre, The Academia, 20 College Road, Level 6, Singapore, 169856, Singapore. .,Duke-NUS Medical School, National University of Singapore, Singapore, Singapore. .,The University of Melbourne, Parkville, Australia.
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9
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Tan B, Sim YC, Chua J, Yusufi D, Wong D, Yow AP, Chin C, Tan ACS, Sng CCA, Agrawal R, Gopal L, Sim R, Tan G, Lamoureux E, Schmetterer L. Developing a normative database for retinal perfusion using optical coherence tomography angiography. Biomed Opt Express 2021; 12:4032-4045. [PMID: 34457397 PMCID: PMC8367249 DOI: 10.1364/boe.423469] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 05/13/2021] [Accepted: 05/13/2021] [Indexed: 05/25/2023]
Abstract
Visualizing and characterizing microvascular abnormalities with optical coherence tomography angiography (OCTA) has deepened our understanding of ocular diseases, such as glaucoma, diabetic retinopathy, and age-related macular degeneration. Two types of microvascular defects can be detected by OCTA: focal decrease because of localized absence and collapse of retinal capillaries, which is referred to as the non-perfusion area in OCTA, and diffuse perfusion decrease usually detected by comparing with healthy case-control groups. Wider OCTA allows for insights into peripheral retinal vascularity, but the heterogeneous perfusion distribution from the macula, parapapillary area to periphery hurdles the quantitative assessment. A normative database for OCTA could estimate how much individual's data deviate from the normal range, and where the deviations locate. Here, we acquired OCTA images using a swept-source OCT system and a 12×12 mm protocol in healthy subjects. We automatically segmented the large blood vessels with U-Net, corrected for anatomical factors such as the relative position of fovea and disc, and segmented the capillaries by a moving window scheme. A total of 195 eyes were included and divided into 4 age groups: < 30 (n=24) years old, 30-49 (n=28) years old, 50-69 (n=109) years old and >69 (n=34) years old. This provides an age-dependent normative database for characterizing retinal perfusion abnormalities in 12×12 mm OCTA images. The usefulness of the normative database was tested on two pathological groups: one with diabetic retinopathy; the other with glaucoma.
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Affiliation(s)
- Bingyao Tan
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore
- NTU Institute for Health Technologies, Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Yin Ci Sim
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Jacqueline Chua
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
| | - Dheo Yusufi
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Damon Wong
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore
- NTU Institute for Health Technologies, Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Ai Ping Yow
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore
- NTU Institute for Health Technologies, Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Calvin Chin
- Duke-NUS Medical School, Singapore
- National Heart Centre Singapore, Singapore
| | - Anna C. S. Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
- Changi General Hospital, Singapore
| | - Chelvin C. A. Sng
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Department of Ophthalmology, National University Hospital, Singapore
| | - Rupesh Agrawal
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Tan Tock Seng Hospital, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | | | - Ralene Sim
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Gavin Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
| | - Ecosse Lamoureux
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
| | - Leopold Schmetterer
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore
- NTU Institute for Health Technologies, Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
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10
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Man REK, Gan ATL, Fenwick EK, Teo KYC, Tan ACS, Cheung GCM, Teo ZL, Kumari N, Wong TY, Cheng CY, Lamoureux EL. Impact of incident age-related macular degeneration and associated vision loss on vision-related quality of life. Br J Ophthalmol 2021; 106:1063-1068. [PMID: 33637622 DOI: 10.1136/bjophthalmol-2020-318269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 02/01/2021] [Accepted: 02/16/2021] [Indexed: 11/03/2022]
Abstract
BACKGROUND We examined the associations between the 6-year incidence of age-related macular degeneration (AMD) and vision-related quality of life (VRQoL), and the contribution of presenting visual acuity (VA), in an Asian population. METHODS Fundus images from the Singapore Chinese Eye Study, a population-based cohort study (baseline: 2009-2011; follow-up: 2015-2017), were graded using a modified Wisconsin age-related maculopathy grading system. Incident AMD was defined as no baseline AMD in both eyes and early/late AMD in the worse eye at follow-up. Presenting VA was assessed using the logarithm of the minimum angle of resolution chart at 4 m under standard lighting conditions with habitual correction. Multiple linear regression models determined the associations between AMD incidence with changes in the Rasch-transformed scores of the Reading, Mobility and Emotional VRQoL domains of the 32-item Impact of Visual Impairment (IVI-32) questionnaire, adjusted for traditional confounders. The contribution of presenting VA to changes in VRQoL was also estimated. RESULTS Of the 2251 participants without AMD at baseline (mean age (SD): 57.7 (9) years, 51.4% women), 101 (4.5%) and 11 (0.5%) developed incident early and late AMD at follow-up, respectively. Incident late AMD was associated with significant 30.3%, 32.5% and 30.9% decrements in Reading, Mobility and Emotional IVI scores, respectively. The contribution of presenting VA ranged between 1.62% and 4.35% of the observed decrements. No significant associations were noted with incident early AMD. CONCLUSION Incident late AMD had a substantial impact on all aspects of VRQoL, with presenting VA contributing only minimally to this longitudinal relationship.
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Affiliation(s)
- Ryan Eyn Kidd Man
- Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore.,Singapore National Eye Centre, Singapore
| | | | | | - Kelvin Yi Chong Teo
- Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore.,Singapore National Eye Centre, Singapore
| | - Anna C S Tan
- Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore.,Singapore National Eye Centre, Singapore
| | - Gemmy Chui Ming Cheung
- Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore.,Singapore National Eye Centre, Singapore
| | - Zhen Ling Teo
- Singapore Eye Research Institute, Singapore.,Singapore National Eye Centre, Singapore
| | - Neelam Kumari
- Singapore Eye Research Institute, Singapore.,Department of Ophthalmology and Visual Sciences, Khoo Teck Puat Hospital, Singapore
| | - Tien Yin Wong
- Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore.,Singapore National Eye Centre, Singapore.,National University of Singapore, Singapore
| | - Ching-Yu Cheng
- Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore.,National University of Singapore, Singapore
| | - Ecosse Luc Lamoureux
- Singapore Eye Research Institute, Singapore .,Duke-NUS Medical School, Singapore.,National University of Singapore, Singapore
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11
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Teo KYC, Jordan-Yu JM, Tan ACS, Yeo IYS, Mathur R, Chan CM, Wong TY, Chakravarthy U, Cheung CMG. Efficacy of a novel personalised aflibercept monotherapy regimen based on polypoidal lesion closure in participants with polypoidal choroidal vasculopathy. Br J Ophthalmol 2021; 106:987-993. [PMID: 33574033 DOI: 10.1136/bjophthalmol-2020-318354] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 01/04/2021] [Accepted: 01/26/2021] [Indexed: 11/03/2022]
Abstract
PURPOSE To compare the efficacy of aflibercept using a personalised versus fixed regimen in treatment-naïve participants with polypoidal choroidal vasculopathy (PCV). DESIGN A 52-week, randomised, open-label, non-inferiority, single-centre study that included participants with symptomatic PCV. Participants were randomised (3:1 ratio) to receive either personalised (n=40) or fixed 8-weekly treatment regimen (n=13). The personalised regimen allowed for either early treat and extend (T&E) after week 12 or late T&E with 3 additional 4-weekly aflibercept injections until week 24 in participants with residual polypoidal lesions (PL) on indocyanine green angiography (ICGA) at week 12. MAIN OUTCOMES AND MEASURES Non-inferiority of personalised to fixed regimen for mean change in best-corrected visual acuity (BCVA) from baseline to week 52 (non-inferiority margin: -5 letters). The key secondary outcomes include reduction in central subfield thickness (CSFT) on optical coherence tomography and the anatomical closure of PL on ICGA. RESULTS Of the 53 participants, the mean (SD) age was 69.2 (8.1) years, 19 (35.8 %) were male. Personalised group was non-inferior to fixed for the primary end point (+8.1 vs +7.9 letters at week 52, respectively; difference 0.16, 95% CI -2.8 to 2.4, p=0.79). There was greater reduction in mean CSFT (SD) in the personalised versus fixed group (-248.8 (169.9) vs -164.8 (148.9) µm, p=0.03). Closure of PL occurred in 21 (55.2%) and 5 (41.6%) of study eyes in personalised and fixed groups, respectively at week 52 (p=0.41). CONCLUSIONS Personalised regimen achieved non-inferior BCVA gain and numerically higher PL closure compared with fixed regimen. TRIAL REGISTRATION NUMBER NCT03117634.
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Affiliation(s)
- Kelvin Yi Chong Teo
- Medical Retina, Singapore National Eye Centre, Singapore.,Retina Research Group, Singapore Eye Research Institute, Singapore.,Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore
| | - Janice Marie Jordan-Yu
- Medical Retina, Singapore National Eye Centre, Singapore.,Retina Research Group, Singapore Eye Research Institute, Singapore
| | - Anna C S Tan
- Medical Retina, Singapore National Eye Centre, Singapore.,Retina Research Group, Singapore Eye Research Institute, Singapore.,Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore
| | - Ian Y S Yeo
- Medical Retina, Singapore National Eye Centre, Singapore.,Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore
| | - Ranjana Mathur
- Medical Retina, Singapore National Eye Centre, Singapore.,Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore
| | - Choi Mun Chan
- Medical Retina, Singapore National Eye Centre, Singapore.,Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore
| | - Tien Yin Wong
- Medical Retina, Singapore National Eye Centre, Singapore.,Retina Research Group, Singapore Eye Research Institute, Singapore.,Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore
| | - Usha Chakravarthy
- Ophthalmology and Vision Sciences, Queen's University Belfast, Belfast, UK
| | - Chui Ming Gemmy Cheung
- Medical Retina, Singapore National Eye Centre, Singapore .,Retina Research Group, Singapore Eye Research Institute, Singapore.,Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore
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12
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Song Y, Tham YC, Chong C, Ong R, Fenner BJ, Cheong KX, Takahashi K, Jordan-Yu JM, Teo KYC, Tan ACS, Cheng CY, Wong TY, Chakravarthy U, Yanagi Y, Cheung GCM. Patterns and Determinants of Choroidal Thickness in a Multiethnic Asian Population: The Singapore Epidemiology of Eye Diseases Study. Ophthalmol Retina 2020; 5:458-467. [PMID: 32858246 DOI: 10.1016/j.oret.2020.08.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 08/16/2020] [Accepted: 08/20/2020] [Indexed: 12/12/2022]
Abstract
PURPOSE To describe the distribution and determinants of choroidal thickness (CT) in participants in a population study based on spectral-domain (SD)-OCT measurements. DESIGN Population-based, cross-sectional study. PARTICIPANTS Ethnic Chinese, Indian, and Malay adults aged more than 50 years without any retinal diseases (e.g., diabetic retinopathy, macular edema, age-related macular degeneration, central serous chorioretinopathy) that might affect the CT were recruited from the Singapore Epidemiology of Eye Diseases Study. METHODS Choroidal imaging was performed by SD-OCT (Spectralis, Heidelberg Engineering, Heidelberg, Germany) in enhanced depth imaging (EDI) mode. Subfoveal choroidal thickness (SFCT) was measured on the foveal line scan by 2 retinal experts independently (YS and KT), and the average was used in the analyses. In Chinese and Indian cohorts in whom macular raster scans were captured, the manufacturer-supplied research software (Heyex SP-X version 6.4.8.116; Heidelberg Engineering) was used to obtain automated segmentation yielding mean choroidal thickness in each of the 9 ETDRS grid sectors. MAIN OUTCOME MEASURES Subfoveal choroidal thickness and regional CT in the 9 ETDRS grid sectors. RESULTS For the SFCT analysis, 2794 eyes of 1619 participants (Chinese, Indian, and Malay ) were included. The mean age was 60.9 years (standard deviation, 7.7), and 797 (49.2%) were male. Mean SFCT was 255.2 μm (standard deviation, 102.6). The normal range of SFCT was 106 to 447 μm (corresponding to 5th and 95th percentile limits of SFCT, respectively). In multivariable models, thinner SFCT was associated with older age, female gender, longer axial length, and Malay (vs. Chinese) ethnicity. In the subset of Chinese and Indian eyes (n = 1842) in whom regional variation was evaluated, the choroid was thickest at the superior and temporal sectors and thinner at the inferior and nasal sectors. CONCLUSIONS Subfoveal choroidal thickness is influenced by age, gender, and ethnicity along with regional differences even within individual eyes. Subfoveal choroidal thickness also shows a wide range in physiologic limits. These data may be used as a reference in future studies.
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Affiliation(s)
- Youngseok Song
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Department of Ophthalmology, Asahikawa Medical University, Asahikawa, Japan
| | - Yih-Chung Tham
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore
| | - Crystal Chong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Ricardo Ong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Beau J Fenner
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Kai Xiong Cheong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Kengo Takahashi
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Department of Ophthalmology, Asahikawa Medical University, Asahikawa, Japan
| | | | - Kelvin Yi Chong Teo
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore
| | - Anna C S Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore
| | - Ching-Yu Cheng
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Tien Yin Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Usha Chakravarthy
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ophthalmology Macular Service, Belfast Health and Social Care Trust and Centre for Population Health, Queen's University Belfast, Belfast, United Kingdom
| | - Yasuo Yanagi
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Department of Ophthalmology, Asahikawa Medical University, Asahikawa, Japan
| | - Gemmy Chui Ming Cheung
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore.
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13
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Tey KY, Teo K, Tan ACS, Devarajan K, Tan B, Tan J, Schmetterer L, Ang M. Optical coherence tomography angiography in diabetic retinopathy: a review of current applications. Eye Vis (Lond) 2019; 6:37. [PMID: 31832448 PMCID: PMC6859616 DOI: 10.1186/s40662-019-0160-3] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 10/14/2019] [Indexed: 01/09/2023]
Abstract
Background Diabetic retinopathy (DR) is a leading cause of vision loss in adults. Currently, the standard imaging technique to monitor and prognosticate DR and diabetic maculopathy is dye-based angiography. With the introduction of optical coherence tomography angiography (OCTA), it may serve as a potential rapid, non-invasive imaging modality as an adjunct. Main text Recent studies on the role of OCTA in DR include the use of vascular parameters e.g., vessel density, intercapillary spacing, vessel diameter index, length of vessels based on skeletonised OCTA, the total length of vessels, vascular architecture and area of the foveal avascular zone. These quantitative measures may be able to detect changes with the severity and progress of DR for clinical research. OCTA may also serve as a non-invasive imaging method to detect diabetic macula ischemia, which may help predict visual prognosis. However, there are many limitations of OCTA in DR, such as difficulty in segmentation between superficial and deep capillary plexus; and its use in diabetic macula edema where the presence of cystic spaces may affect image results. Future applications of OCTA in the anterior segment include detection of anterior segment ischemia and iris neovascularisation associated with proliferative DR and risk of neovascular glaucoma. Conclusion OCTA may potentially serve as a useful non-invasive imaging tool in the diagnosis and monitoring of diabetic retinopathy and maculopathy in the future. Future studies may demonstrate how quantitative OCTA measures may have a role in detecting early retinal changes in patients with diabetes.
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Affiliation(s)
- Kai Yuan Tey
- Hobart Clinical School, Level 3, 43 Collins Street, Hobart, TAS 7000 Australia
| | - Kelvin Teo
- 2Singapore National Eye Centre, 11 Third Hospital Ave, Singapore, 168751 Singapore
| | - Anna C S Tan
- 2Singapore National Eye Centre, 11 Third Hospital Ave, Singapore, 168751 Singapore
| | - Kavya Devarajan
- 3Singapore Eye Research Institute, 20 College Road Discovery Tower, Level 6 The Academia, Singapore, 169856 Singapore
| | - Bingyao Tan
- 3Singapore Eye Research Institute, 20 College Road Discovery Tower, Level 6 The Academia, Singapore, 169856 Singapore
| | - Jacqueline Tan
- 3Singapore Eye Research Institute, 20 College Road Discovery Tower, Level 6 The Academia, Singapore, 169856 Singapore
| | - Leopold Schmetterer
- 3Singapore Eye Research Institute, 20 College Road Discovery Tower, Level 6 The Academia, Singapore, 169856 Singapore
| | - Marcus Ang
- 4Singapore National Eye Centre, 11 Third Hospital Ave, Singapore 168751; Duke-NUS Medical School, 8 College Rd, Singapore, 169857 Singapore
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14
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Fenner BJ, Ting DSW, Tan ACS, Teo K, Chan CM, Mathur R, Yeo IYS, Wong TY, Wong EYM, Cheung CMG. Real-World Treatment Outcomes of Age-Related Macular Degeneration and Polypoidal Choroidal Vasculopathy in Asians. Ophthalmol Retina 2019; 4:403-414. [PMID: 31953109 DOI: 10.1016/j.oret.2019.10.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 10/06/2019] [Accepted: 10/28/2019] [Indexed: 11/26/2022]
Abstract
PURPOSE To describe the 12-month outcomes of treatment-naïve eyes with choroidal neovascularization (CNV) resulting from age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) after initiation of intravitreal anti-vascular endothelial growth factor (VEGF) monotherapy or combination therapy with verteporfin photodynamic therapy (PDT). DESIGN A 12-month single-center, retrospective, comparative, nonrandomized cohort study. PARTICIPANTS Patients with AMD or PCV who initiated intravitreal anti-VEGF therapy during 2015. METHODS Demographics, visual outcomes, OCT, and treatment data were collected at baseline and months 1, 3, 6, and 12 after treatment initiation. Multivariate analysis was performed to identify baseline features predictive of visual maintenance and improvement after 12 months of treatment. MAIN OUTCOME MEASURES Primary end point was visual acuity (VA) change from baseline to month 12. Secondary end points were treatment exposure and change in central subfield thickness on OCT. RESULTS A total of 364 patients (165 AMD and 199 PCV) were included. Baseline vision was 41 and 43 logarithm of the minimum angle of resolution (logMAR) letters for AMD and PCV patients, respectively. Patients with AMD and PCV received 5.5 and 5.3 injections (5.0 monotherapy vs. 5.6 combination therapy; mean, 1.2 PDT sessions), respectively. Patients with AMD gained 4.7 logMAR letters after 12 months (P = 0.002), whereas PCV patients gained 6.6 logMAR letters (P = 0.001) and 10.8 logMAR letters (P < 0.001) for monotherapy and combination therapy, respectively. Only patients with presenting VA of fewer than 35 letters (Snellen equivalent, 6/60) achieved significant visual improvement (10.4 letters for AMD, 17.1 letters for PCV with monotherapy, and 35.5 letters for PCV with combination therapy). Predictors of VA gain included number of intravitreal injections (AMD and PCV adjusted odds ratio, 12.1 [P = 0.001] and 12.5 [P = 0.004] for ≥7 injections, respectively) and baseline VA of 20 logMAR letters or fewer (adjusted odds ratio, 3.8 and 10.6 for AMD and PCV, respectively). Age, gender, race, use of PDT or focal laser therapy, and central subfield thickness were not predictive of significant visual gain at 12 months. CONCLUSIONS In Asian patients, treatment of AMD with anti-VEGF therapy yielded 12-month visual outcomes comparable with those of other real-world studies from Western populations but poorer than those of controlled trials. In contrast, for PCV eyes, anti-VEGF monotherapy and combination therapy with PDT yielded comparable outcomes as those of controlled clinical trials.
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Affiliation(s)
- Beau J Fenner
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Republic of Singapore
| | - Daniel S W Ting
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Republic of Singapore; Duke-NUS Graduate Medical School, Eye Academic Clinical Program, Singapore, Republic of Singapore
| | - Anna C S Tan
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Republic of Singapore; Duke-NUS Graduate Medical School, Eye Academic Clinical Program, Singapore, Republic of Singapore
| | - Kelvin Teo
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Republic of Singapore; Duke-NUS Graduate Medical School, Eye Academic Clinical Program, Singapore, Republic of Singapore
| | - Choi Mun Chan
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Republic of Singapore; Duke-NUS Graduate Medical School, Eye Academic Clinical Program, Singapore, Republic of Singapore
| | - Ranjana Mathur
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Republic of Singapore; Duke-NUS Graduate Medical School, Eye Academic Clinical Program, Singapore, Republic of Singapore
| | - Ian Y S Yeo
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Republic of Singapore; Duke-NUS Graduate Medical School, Eye Academic Clinical Program, Singapore, Republic of Singapore
| | - Tien Y Wong
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Republic of Singapore; Duke-NUS Graduate Medical School, Eye Academic Clinical Program, Singapore, Republic of Singapore
| | - Edmund Y M Wong
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Republic of Singapore; Duke-NUS Graduate Medical School, Eye Academic Clinical Program, Singapore, Republic of Singapore
| | - Chui Ming Gemmy Cheung
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Republic of Singapore; Duke-NUS Graduate Medical School, Eye Academic Clinical Program, Singapore, Republic of Singapore.
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15
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Curcio CA, Tan ACS, Lengyel I. Calcium, Diet, Imaging, and Age-Related Macular Degeneration. JAMA Ophthalmol 2019; 137:1333-1334. [PMID: 31536097 DOI: 10.1001/jamaophthalmol.2019.2725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Christine A Curcio
- Department of Ophthalmology and Visual Sciences, EyeSight Foundation of Alabama Vision Research Laboratories, School of Medicine, University of Alabama at Birmingham
| | - Anna C S Tan
- Singapore National Eye Center, Singapore Eye Research Institute, Singapore
| | - Imre Lengyel
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom
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16
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Abstract
New treatment modalities for the management of central serous chorioretinopathy (CSC) now exist. While acute CSC generally resolves without the requirement for intervention, chronic CSC has been associated with persistent disruption in visual function. Current treatment approaches include photodynamic therapy, oral aldosterone antagonism and subthreshold multifocal laser. There has also been further investigation into a number of new treatments including antivascular endothelial growth factor treatment. Further investigation using developing optical coherence tomography imaging is helping to determine biomarkers of CSC activity, potential indicators of treatment response and indications of chronicity of disease activity. Further comparative study is required to determine the effectiveness of different forms of treatment in a range of patients with varied demographics, aetiology and chronicity of disease.
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Affiliation(s)
- Daren Hanumunthadu
- Moorfields Eye Hospital National Health Service Foundation Trust, London, UK
| | - Anna C S Tan
- Singapore National Eye Centre; Department of Medical Retina, Singapore Eye Research Institute; Department of Medical Retina, Duke-NUS Medical School, Singapore
| | - Sumit Randhir Singh
- Smt. Kanuri Santhamma Retina Vitreous Centre, LV Prasad Eye Institute, Hyderabad, Telangana, India
| | - Niroj Kumar Sahu
- Smt. Kanuri Santhamma Retina Vitreous Centre, LV Prasad Eye Institute, Hyderabad, Telangana, India
| | - Jay Chhablani
- Smt. Kanuri Santhamma Retina Vitreous Centre, LV Prasad Eye Institute, Hyderabad, Telangana, India
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17
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Tan ACS, Pilgrim MG, Fearn S, Bertazzo S, Tsolaki E, Morrell AP, Li M, Messinger JD, Dolz-Marco R, Lei J, Nittala MG, Sadda SR, Lengyel I, Freund KB, Curcio CA. Calcified nodules in retinal drusen are associated with disease progression in age-related macular degeneration. Sci Transl Med 2018; 10:eaat4544. [PMID: 30404862 PMCID: PMC10721335 DOI: 10.1126/scitranslmed.aat4544] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 08/10/2018] [Accepted: 10/17/2018] [Indexed: 12/17/2023]
Abstract
Drusen are lipid-, mineral-, and protein-containing extracellular deposits that accumulate between the basal lamina of the retinal pigment epithelium (RPE) and Bruch's membrane (BrM) of the human eye. They are a defining feature of age-related macular degeneration (AMD), a common sight-threatening disease of older adults. The appearance of heterogeneous internal reflectivity within drusen (HIRD) on optical coherence tomography (OCT) images has been suggested to indicate an increased risk of progression to advanced AMD. Here, in a cohort of patients with AMD and drusen, we show that HIRD indicated an increased risk of developing advanced AMD within 1 year. Using multimodal imaging in an independent cohort, we demonstrate that progression to AMD was associated with increasing degeneration of the RPE overlying HIRD. Morphological analysis of clinically imaged cadaveric human eye samples revealed that HIRD was formed by multilobular nodules. Nanoanalytical methods showed that nodules were composed of hydroxyapatite and that they differed from spherules and BrM plaques, other refractile features also found in the retinas of patients with AMD. These findings suggest that hydroxyapatite nodules may be indicators of progression to advanced AMD and that using multimodal clinical imaging to determine the composition of macular calcifications may help to direct therapeutic strategies and outcome measures in AMD.
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Affiliation(s)
- Anna C S Tan
- Vitreous Retina Macula Consultants of New York, New York, NY 10022, USA
- LuEsther T. Mertz Retinal Research Center, Manhattan, Eye, Ear and Throat Hospital, New York, NY 10075, USA
- Singapore National Eye Center/Singapore Eye Research Institute Singapore, Singapore 168751, Singapore
- Duke-NUS Singapore, Singapore 168751, Singapore
| | - Matthew G Pilgrim
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
- Division of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, University College London, London WC1X 8LD, UK
| | - Sarah Fearn
- Department of Materials, Imperial College London, London SW7 2AZ, UK
| | - Sergio Bertazzo
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, UK
| | - Elena Tsolaki
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, UK
| | - Alexander P Morrell
- Material Physics, Aston University, Aston Express Way, Birmingham B4 7ET, UK
| | - Miaoling Li
- Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 32594-0019, USA
| | - Jeffrey D Messinger
- Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 32594-0019, USA
| | - Rosa Dolz-Marco
- Vitreous Retina Macula Consultants of New York, New York, NY 10022, USA
- LuEsther T. Mertz Retinal Research Center, Manhattan, Eye, Ear and Throat Hospital, New York, NY 10075, USA
| | - Jianqin Lei
- Doheny Image Reading Center, Doheny Eye Institute, Los Angeles, CA 90033, USA
| | - Muneeswar G Nittala
- Doheny Image Reading Center, Doheny Eye Institute, Los Angeles, CA 90033, USA
| | - Srinivas R Sadda
- Doheny Image Reading Center, Doheny Eye Institute, Los Angeles, CA 90033, USA
- Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Imre Lengyel
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK.
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast BT9 7BL, UK
| | - K Bailey Freund
- Vitreous Retina Macula Consultants of New York, New York, NY 10022, USA
- LuEsther T. Mertz Retinal Research Center, Manhattan, Eye, Ear and Throat Hospital, New York, NY 10075, USA
- Department of Ophthalmology, New York University Langone School of Medicine, New York, NY 10016, USA
| | - Christine A Curcio
- Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 32594-0019, USA
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Tan ACS, Tan GS, Denniston AK, Keane PA, Ang M, Milea D, Chakravarthy U, Cheung CMG. An overview of the clinical applications of optical coherence tomography angiography. Eye (Lond) 2018; 32:262-286. [PMID: 28885606 PMCID: PMC5811700 DOI: 10.1038/eye.2017.181] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 07/15/2017] [Indexed: 12/15/2022] Open
Abstract
Optical coherence tomography angiography (OCTA) has emerged as a novel, non-invasive imaging modality that allows the detailed study of flow within the vascular structures of the eye. Compared to conventional dye angiography, OCTA can produce more detailed, higher resolution images of the vasculature without the added risk of dye injection. In our review, we discuss the advantages and disadvantages of this new technology in comparison to conventional dye angiography. We provide an overview of the current OCTA technology available, compare the various commercial OCTA machines technical specifications and discuss some future software improvements. An approach to the interpretation of OCTA images by correlating images to other multimodal imaging with attention to identifying potential artefacts will be outlined and may be useful to ophthalmologists, particularly those who are currently still unfamiliar with this new technology. This review is based on a search of peer-reviewed published papers relevant to OCTA according to our current knowledge, up to January 2017, available on the PubMed database. Currently, many of the published studies have focused on OCTA imaging of the retina, in particular, the use of OCTA in the diagnosis and management of common retinal diseases such as age-related macular degeneration and retinal vascular diseases. In addition, we describe clinical applications for OCTA imaging in inflammatory diseases, optic nerve diseases and anterior segment diseases. This review is based on both the current literature and the clinical experience of our individual authors, with an emphasis on the clinical applications of this imaging technology.
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Affiliation(s)
- A C S Tan
- Singapore National Eye Center, Singapore Eye Research Institute, Singapore, Singapore
- Singapore Eye Research Institute, Singapore Singapore
- Duke-NUS Medical School, Singapore, Singapore
| | - G S Tan
- Singapore National Eye Center, Singapore Eye Research Institute, Singapore, Singapore
- Singapore Eye Research Institute, Singapore Singapore
- Duke-NUS Medical School, Singapore, Singapore
| | - A K Denniston
- Department of Ophthalmology, University Hospitals of Birmingham NHS Foundation Trust, Birmingham, UK
- Academic Unit of Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
- National Institute for Health Research (NIHR) Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
| | - P A Keane
- National Institute for Health Research (NIHR) Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
| | - M Ang
- Singapore National Eye Center, Singapore Eye Research Institute, Singapore, Singapore
- Singapore Eye Research Institute, Singapore Singapore
- Duke-NUS Medical School, Singapore, Singapore
| | - D Milea
- Singapore National Eye Center, Singapore Eye Research Institute, Singapore, Singapore
- Singapore Eye Research Institute, Singapore Singapore
- Duke-NUS Medical School, Singapore, Singapore
| | - U Chakravarthy
- Department of Ophthalmology, Queen's University of Belfast, Royal Victoria Hospital, Belfast, Northern Ireland
| | - C M G Cheung
- Singapore National Eye Center, Singapore Eye Research Institute, Singapore, Singapore
- Singapore Eye Research Institute, Singapore Singapore
- Duke-NUS Medical School, Singapore, Singapore
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Tan ACS, Dansingani KK, Curcio CA, Freund KB. Author Response: The Evolution of the Plateau, an Optical Coherence Tomography Signature Seen in Geographic Atrophy. Invest Ophthalmol Vis Sci 2017; 58:6196. [PMID: 29222549 PMCID: PMC5724397 DOI: 10.1167/iovs.17-23339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Anna C S Tan
- Vitreous Retina Macula Consultants of New York, New York, New York, United States.,The LuEsther T. Mertz Retinal Research Center, New York, New York, United States.,Singapore National Eye Center/Singapore Eye Research Institute, Singapore
| | - Kunal K Dansingani
- Vitreous Retina Macula Consultants of New York, New York, New York, United States.,The LuEsther T. Mertz Retinal Research Center, New York, New York, United States.,University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States
| | - Christine A Curcio
- Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, Alabama, United States; and the
| | - K Bailey Freund
- Vitreous Retina Macula Consultants of New York, New York, New York, United States.,The LuEsther T. Mertz Retinal Research Center, New York, New York, United States.,Department of Ophthalmology, New York University School of Medicine, New York, New York, United States
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Fenner BJ, Tan GSW, Tan ACS, Yeo IYS, Wong TY, Cheung GCM. Identification of imaging features that determine quality and repeatability of retinal capillary plexus density measurements in OCT angiography. Br J Ophthalmol 2017; 102:509-514. [DOI: 10.1136/bjophthalmol-2017-310700] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 07/15/2017] [Accepted: 07/25/2017] [Indexed: 11/04/2022]
Abstract
PurposeOptical coherence tomography angiography (OCT-A) potentially allows for rapid and non-invasive quantification of retinal capillary plexus density in various disease states. This study aims to identify the key features that influenced the repeatability of OCT-A measurements.MethodsWe obtained OCT-A images on two separate visits in 44 healthy eyes from 44 subjects, each imaged with using the Topcon DRI OCT Triton imaging system. The parafoveal vessel density within a 1.5 mm radius centred over the fovea was obtained with the built-in tool for the superficial and deep retinal plexuses. Repeatability of vessel density was determined by intraclass correlation (ICC) and mean variation. We evaluated several image parameters to determine their influence on the repeatability of vessel density measurement in each of the two capillary plexuses.ResultsThe mean age of the subjects was 70.2±9.2 years, with 64% males. Mean parafoveal vessel density measurements for the first and second visits were 53.3±11.1 and 53.3±10.3 for the superficial plexus and 27.3±8.59 and 27.0±8.78 for the deep plexus. ICC analyses demonstrated that high fine vessel visibility, the absence of motion artefact and software-derived image quality score of 60 or above were necessary to obtain a good (ICC>0.6) or excellent (ICC>0.75) repeatability.ConclusionsOur study identified the imaging parameters that determined the repeatability of quantitative retinal vessel density measurements. These findings have implications in determining if OCT-A images can be used to accurately evaluate serial changes in retinal vessel density.
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Tan ACS, Astroz P, Dansingani KK, Slakter JS, Yannuzzi LA, Curcio CA, Freund KB. The Evolution of the Plateau, an Optical Coherence Tomography Signature Seen in Geographic Atrophy. Invest Ophthalmol Vis Sci 2017; 58:2349-2358. [PMID: 28437524 PMCID: PMC5413303 DOI: 10.1167/iovs.16-21237] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Purpose Histologic details of progression routes to geographic atrophy (GA) in AMD are becoming available through optical coherence tomography (OCT). We studied the origins and evolution of an OCT signature called plateau in eyes with GA and suggested a histologic correlate. Methods Serial eye-tracked OCT scans and multimodal imaging were acquired from eight eyes of seven patients with GA and plateau signatures over a mean follow-up of 7.7 years (range, 3.7–11.6). The histology of unrelated donor eyes with AMD was reviewed. Results Drusenoid pigment epithelial detachment (PED) on OCT imaging progressed into wide-based mound-like signatures with flattened apices characterized by a hyporeflective yet heterogeneous interior and an overlying hyperreflective exterior, similar to outer retinal corrugations previously ascribed to persistent basal laminar deposit (BLamD) but larger. These new signatures are described as “plateaus.” An initial increase of the PED volume and hyporeflectivity of its contents was followed by a decrease in PED volume and thinning of an overlying hyperreflective band attributable to the loss of the overlying RPE leaving persistent BLamD. Both imaging and histology revealed persistent BLamD with defects through which gliotic Müller cell processes pass. Conclusions Plateaus can be traced back to drusenoid PEDs on OCT imaging. We hypothesize that during progressive RPE atrophy, Müller cell extension through focal defects in the residual persistent BLamD may contribute to the heterogeneous internal reflectivity of these entities. The role of Müller cell activation and extension in the pathogenesis of AMD should be explored in future studies.
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Affiliation(s)
- Anna C S Tan
- Vitreous Retina Macula Consultants of New York, New York, New York, United States 2The LuEsther T. Mertz Retinal Research Center, New York, New York, United States 3Singapore National Eye Center/Singapore Eye Research Institute/Duke-NUS Medical School, Singapore, Singapore
| | - Polina Astroz
- Vitreous Retina Macula Consultants of New York, New York, New York, United States 4Department of Ophthalmology, Intercity Hospital and University Paris Est, Creteil, France
| | - Kunal K Dansingani
- Vitreous Retina Macula Consultants of New York, New York, New York, United States 2The LuEsther T. Mertz Retinal Research Center, New York, New York, United States 5Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska, United States
| | - Jason S Slakter
- Vitreous Retina Macula Consultants of New York, New York, New York, United States
| | - Lawrence A Yannuzzi
- Vitreous Retina Macula Consultants of New York, New York, New York, United States 2The LuEsther T. Mertz Retinal Research Center, New York, New York, United States
| | - Christine A Curcio
- Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, Alabama, United States
| | - K Bailey Freund
- Vitreous Retina Macula Consultants of New York, New York, New York, United States 2The LuEsther T. Mertz Retinal Research Center, New York, New York, United States 7Department of Ophthalmology, New York University School of Medicine, New York, New York, United States
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Tan ACS, Balaratnasingam C, Yannuzzi LA. Treatment of Macular Telangiectasia Type 2 With Carotenoid Supplements Containing Meso-Zeaxanthin: A Pilot Study. Ophthalmic Surg Lasers Imaging Retina 2017; 47:528-35. [PMID: 27327282 DOI: 10.3928/23258160-20160601-04] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 04/19/2016] [Indexed: 11/20/2022]
Abstract
BACKGROUND AND OBJECTIVE To assess the outcomes of patients with macular telangiectasia type 2 (MacTel 2) in response to lutein (L), meso-zeaxanthin (M), and zeaxanthin (Z) supplements (LMZ3). PATIENTS AND METHODS Thirteen patients diagnosed with MacTel 2 were started on lutein 10 mg, meso-zeaxanthin 10 mg, and zeaxanthin 2 mg and were followed-up for a mean period of 15.7 months ± 4.85 months. RESULTS Visual acuity improved in three patients (13%), and there was a reduction in the percentage of patients who had worsening vision (25% to 4%; P < .05). Optical coherence tomography changes showed a reduction in the number of cavitations and the largest diameter of the cavitation after the LMZ3 supplements were started. The largest diameter of photoreceptor disruption showed mild improvement in the first 6 months after LMZ3 supplements were started. CONCLUSION LMZ3 supplements may stabilize vision and improve the cavitations in patients with MacTel 2. Larger randomized, controlled studies are required to verify these pilot results. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:528-535.].
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Abstract
PURPOSE To describe the multimodal imaging findings observed unilaterally in a patient with Best disease due to a p.G15D mutation in the BEST1 gene. METHODS The clinical history of a 62-year-old female patient with unilateral Best disease was reviewed. Retinal findings were documented by clinical examination and multimodal imaging. RESULTS Posterior segment examination of the patient's right eye demonstrated retinal pigment epithelium hypopigmentation and clumping in the central macula beneath a chronic shallow serous retinal detachment (SRD), confirmed by optical coherence tomography. Fluorescein angiography showed central staining with no evidence of focal leakage or choroidal neovascularization, and correlated with the hypoautofluorescence seen on fundus autofluorescence. There was no evidence of choroidal hyperpermeability on indocyanine green angiography, nor was there any neovascularization detected on optical coherence tomography-angiography. The left eye appeared normal with all imaging modalities. CONCLUSION Best disease is an autosomal dominant disease that is generally bilateral. We present a case of a unilateral Best disease with serous retinal detachment in a patient with a p.G15D mutation in BEST1. Best disease should be considered in the differential diagnosis of serous retinal detachment and may masquerade as central serous chorioretinopathy.
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Affiliation(s)
- Talia R Kaden
- *Vitreous-Retina-Macula Consultants of New York, New York, New York; †The LuEsther T. Mertz Retinal Research Center, New York, New York; ‡Department of Ophthalmology, New York University School of Medicine, New York, New York; §Singapore National Eye Center, Singapore Eye Research Institute, Singapore, Singapore; and ¶NJ Retina, New Jersey
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Dolz-Marco R, Litts KM, Tan ACS, Freund KB, Curcio CA. The Evolution of Outer Retinal Tubulation, a Neurodegeneration and Gliosis Prominent in Macular Diseases. Ophthalmology 2017; 124:1353-1367. [PMID: 28456420 DOI: 10.1016/j.ophtha.2017.03.043] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 03/21/2017] [Accepted: 03/21/2017] [Indexed: 11/26/2022] Open
Abstract
PURPOSE To document outer retinal tubulation (ORT) formation in advanced retinal disorders. DESIGN Retrospective, observational study. PARTICIPANTS Consecutive cases with retinal diseases showing outer retinal disruption and atrophy of the retinal pigment epithelium (RPE) associated with ORT on spectral-domain (SD) optical coherence tomography (OCT) at the final available visit. METHODS Cross-sectional SD OCT scans showing ORT at the last available visit were compared with eye-tracked baseline scans. Only patients showing the formation of ORT over time with absence of ORT at baseline were analyzed. MAIN OUTCOME MEASURES Steps in ORT formation based on shapes of the external limiting membrane (ELM) descent (flat, curved, reflected, and scrolled) at the border of outer retinal and RPE atrophy, ORT characteristics (open, closed), and time between steps through a long-term follow-up. RESULTS From 170 eyes of 86 patients with ORT, 38 eyes of 30 patients (11 men, 19 women) with a mean age of 78.87 years (range, 56-96 years) met inclusion criteria. Of these 38 eyes, 23 (60%) had geographic atrophy secondary to age-related macular degeneration (AMD) and 2 eyes (5%) had geographic atrophy secondary to pattern dystrophy. Twelve eyes (32%) had neovascular AMD and 1 eye (3%) had neovascularization secondary to pseudoxanthoma elasticum, all showing similar ORT formative steps. Seventy-three different retinal areas (1434 cross-sectional images) were analyzed over a mean follow-up of 69.5 months (range, 21-93 months). At 73 borders, grading of eye-tracked follow-up SD OCT line scans showed a flat ELM descent at least once at 34 borders (47%), a curved ELM at 47 borders (64%), a reflected ELM at 37 borders (51%), and a scrolled ELM at 24 borders (33%). Of 81 ORTs, 73 (90%) were closed and 8 (10%) were open. The mean time for ORT formation was 14.9 months (range, 1.4-71.3 months). CONCLUSIONS We propose progressive steps in the development of ORT and analyze the time of progression between these steps. Analyzing the borders of atrophy to determine the origin of ORT provides new insights into the pathophysiology of advanced retinal disease highlighting a role for Müller cells and may inform future therapeutic strategies.
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Affiliation(s)
- Rosa Dolz-Marco
- Vitreous Retina Macula Consultants of New York, New York; LuEsther T. Mertz Retinal Research Center, Manhattan Eye, Ear and Throat Hospital, New York, New York; Unit of Macula, Health Research Institute, University and Polytechnic Hospital La Fe, Valencia, Spain
| | - Katie M Litts
- Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, Alabama
| | - Anna C S Tan
- Vitreous Retina Macula Consultants of New York, New York; LuEsther T. Mertz Retinal Research Center, Manhattan Eye, Ear and Throat Hospital, New York, New York; Singapore National Eye Center, Singapore Eye Research Institute, Singapore, Republic of Singapore
| | - K Bailey Freund
- Vitreous Retina Macula Consultants of New York, New York; LuEsther T. Mertz Retinal Research Center, Manhattan Eye, Ear and Throat Hospital, New York, New York; Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University College of Physicians and Surgeons, New York, New York; Department of Ophthalmology, New York University School of Medicine, New York, New York.
| | - Christine A Curcio
- Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, Alabama
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Phasukkijwatana N, Tan ACS, Chen X, Freund KB, Sarraf D. Optical coherence tomography angiography of type 3 neovascularisation in age-related macular degeneration after antiangiogenic therapy. Br J Ophthalmol 2016; 101:597-602. [DOI: 10.1136/bjophthalmol-2016-308815] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 05/19/2016] [Accepted: 07/14/2016] [Indexed: 11/04/2022]
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Tan ACS, Fleckenstein M, Schmitz-Valckenberg S, Holz FG. Clinical Application of Multicolor Imaging Technology. Ophthalmologica 2016; 236:8-18. [PMID: 27404384 DOI: 10.1159/000446857] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 05/12/2016] [Indexed: 11/19/2022]
Abstract
PURPOSE To assess the clinical application of multicolor imaging by confocal scanning laser ophthalmoscopy (cSLO). METHODS Retinal imaging was performed in 76 patients including cSLO multicolor imaging (SPECTRALIS SD-OCT, Heidelberg Engineering, Heidelberg, Germany) and color fundus photography (CFP). RESULTS The use of confocal optics, reduced light scatter and automated eye tracking enable high-resolution cSLO reflectance images. Compared to CFP, the appearance of pigment alterations and hemorrhages were some of the differences observed. Various artifacts including those derived from optical media alterations need to be considered when interpreting images. Specific pathological findings including epiretinal membranes, fibrovascular proliferations, and reticular pseudodrusen may be better visualized on multicolor images. CONCLUSIONS When using multicolor imaging, ophthalmologists need to be mindful about differences in the appearance of pathological changes and artifacts. Multicolor imaging may offer information over and above conventional CFP; it can be performed through undilated pupils and is less affected by media opacities.
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Affiliation(s)
- Anna C S Tan
- Department of Ophthalmology, University of Bonn, Bonn, Germany
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27
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Tan ACS, Chen L, Png R, Chia A. The diagnosis and assessment of visual function in Singaporean children with electrophysiology: 10-year results. Doc Ophthalmol 2016; 132:189-99. [PMID: 27084553 DOI: 10.1007/s10633-016-9539-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 04/07/2016] [Indexed: 11/30/2022]
Abstract
PURPOSE To study the clinical use and efficacy of electrophysiology in children. METHODS This was a retrospective review of all children aged <16 years, who were referred to the Visual Electrophysiology Laboratory at the Singapore National Eye Center between 2003 and 2013. RESULTS A total of 586 children, median age 8 years (range 0.15-16), were referred for a variety of reasons including investigation of poor vision (40 %), suspected retinal disease or optic nerve/cortical dysfunction (17 %), nystagmus (13 %) and screening or monitoring of a variety of ocular or neurological conditions (12 %). The number of children with vision 6/15 or worse was 418 (71 %), and 103 (18 %) had vision 6/120 or worse in at least one eye. The most common pathology noted was retinal dystrophy or dysfunction (41 %) or optic nerve/cortical dysfunction (12 %). In 30 %, visual electrophysiology was within normal limits, and in 6 %, a conclusive diagnosis could not be obtained. CONCLUSION Electrophysiology testing played an important role in the assessment of children and added to the clinical management of the patient.
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Affiliation(s)
- Anna C S Tan
- Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore. .,Singapore Eye Research Institute, Singapore, Singapore.
| | - LiYu Chen
- Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore
| | - Rena Png
- Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore
| | - Audrey Chia
- Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Singapore Eye Research Institute, Singapore, Singapore
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Jung JJ, Chae B, Tan ACS, Patel SN, Freund KB. Author Response: Use of Clopidogrel and Poor Visual Outcome. Invest Ophthalmol Vis Sci 2015; 56:7052. [PMID: 26529039 DOI: 10.1167/iovs.15-18289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Jesse J Jung
- East Bay Retina Consultants Inc., Oakland, California, United States
| | - Bora Chae
- Department of Ophthalmology, New York University School of Medicine, New York, New York, United States
| | - Anna C S Tan
- Vitreous Retina Macula Consultants of New York, New York, New York, United States; 4LuEsther T. Mertz Retinal Research Center, Manhattan Eye, Ear and Throat Hospital, New York, New York, United States; 5Singapore National Eye Centre/ Singapore Eye Researc
| | - Samir N Patel
- Weill Cornell Medical College, New York, New York, United States
| | - K Bailey Freund
- Department of Ophthalmology, New York University School of Medicine, New York, New York, United States; 3Vitreous Retina Macula Consultants of New York, New York, New York, United States; 4LuEsther T. Mertz Retinal Research Center, Manhattan Eye, Ear and
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Tan ACS, Farooqui S, Li X, Tan YL, Cullen J, Lim W, Leng SL, Looi A, Tow S. Ocular manifestations and the clinical course of carotid cavernous sinus fistulas in Asian patients. Orbit 2014; 33:45-51. [PMID: 24195725 DOI: 10.3109/01676830.2013.851253] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
PURPOSE To study the clinical course with regard to both the angiographic and visual outcomes of carotid cavernous fistulas (CCFs). BACKGROUND Carotid cavernous sinus fistulas (CCFs) are conditions which often present with ocular signs and symptoms. The clinical presentation of CCFs is varied according to the anatomy, haemodynamics and size of the CCF. CCFs causing significant symptoms or vision loss should be treated with embolization. METHODS This is a retrospective review of the medical records of all CCF cases seen in the Singapore National Eye Centre from September 2002 to December 2011. RESULTS 45 patients who had confirmed CCF on conventional cerebral angiography were included. Anterior draining CCFs presented with orbital congestion while posterior draining CCFs presented with pain, diplopia and cranial nerve palsies. Mild residual symptoms were still present in 85% of treated direct CCFs despite complete angiographic closure however 52% of treated dural CCFs had complete resolution of symptoms despite only half of those achieving angiographic closure. Treated and untreated dural CCFs had similar outcomes (87% versus 76% recovered or improved (p > 0.05)). Poor outcomes can result from residual diplopia or vision loss from complications of the CCF itself (e.g. compressive optic neuropathy, glaucoma, retinopathy) or complications from CCF embolization treatment (e.g. central retinal artery occlusion). CONCLUSION Presenting symptoms and signs are related to the angiographic drainage of CCFs. Angiographic outcomes after embolization treatment may not always correlate with clinical outcomes.
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Tan XW, Riau A, Shi ZL, Tan ACS, Neoh KG, Khor KA, Beuerman RW, Tan D, Mehta JS. In vitro effect of a corrosive hostile ocular surface on candidate biomaterials for keratoprosthesis skirt. Br J Ophthalmol 2012; 96:1252-8. [PMID: 22802307 PMCID: PMC3432489 DOI: 10.1136/bjophthalmol-2012-301633] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Aim Keratoprosthesis (KPro) devices are prone to long-term corrosion and microbiological assault. The authors aimed to compare the inflammatory response and material dissolution properties of two candidate KPro skirt materials, hydroxyapatite (HA) and titania (TiO2) in a simulated in vitro cornea inflammation environment. Methods Lipopolysaccharide-stimulated cytokine secretions were evaluated with human corneal fibroblasts on both HA and TiO2. Material specimens were subjected to electrochemical and long-term incubation test with artificial tear fluid (ATF) of various acidities. Topography and surface roughness of material discs were analysed by scanning electron microscopy and atomic force microscopy. Results There were less cytokines secreted from human corneal fibroblasts seeded on TiO2 substrates as compared with HA. TiO2 was more resistant to the corrosion effect caused by acidic ATF in contrast to HA. Moreover, the elemental composition of TiO2 was more stable than HA after long-term incubation with ATF. Conclusions TiO2 is more resistant to inflammatory degradation and has a higher corrosion resistance as compared with HA, and in this regard may be a suitable material to replace HA as an osteo-odonto-keratoprosthesis skirt. This would reduce resorption rates for KPro surgery.
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Affiliation(s)
- Xiao Wei Tan
- Tissue Engineering and Stem Cell Research Group, Singapore Eye Research Institute, Singapore
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Tan ACS, Tay WT, Zheng YF, Tan AG, Wang JJ, Mitchell P, Wong TY, Lamoureux EL. The impact of bilateral or unilateral cataract surgery on visual functioning: when does second eye cataract surgery benefit patients? Br J Ophthalmol 2012; 96:846-51. [PMID: 22408232 DOI: 10.1136/bjophthalmol-2011-301233] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM To examine the impact of bilateral or unilateral cataract surgery on visual functioning. METHODS The Singapore Malay Eye Study is a population-based study of 3280 Singapore Malay patients aged 40-80 years, of which 3225 had data available for inclusion. Cataracts were graded from digital lens photographs according to the Wisconsin scale. Study subjects were categorised as having: bilateral cataract surgery performed; unilateral cataract surgery performed with minimal cataract in the fellow eye; unilateral cataract surgery performed with significant cataract in the fellow eye; and bilateral cataract. Visual functioning was assessed using the modified VF-9 scale culturally adapted for Singaporean individuals, validated by Rasch analysis. The overall Rasch-modified vision-specific functioning score was compared across the four groups after adjusting for confounders such as age, gender, ocular and systemic comorbidities. RESULTS Persons with bilateral cataract had poorer visual functioning than those who had bilateral cataract surgery (mean visual functioning scores 3.38 vs 3.11, respectively, p=0.029). When compared with bilateral surgery, visual functioning improvements among patients with unilateral cataract surgery depended on the status of the fellow eye, with improvements only seen if the fellow eye had significant cataract (mean visual functioning scores 2.81 vs 3.25, p=0.019) or poor visual acuity (mean visual functioning scores 2.78 vs 3.25, p=0.018) after adjusting for confounders. CONCLUSIONS Bilateral cataract surgery was associated with greater visual functioning over unilateral cataract surgery when the fellow eye had a significant cataract or poor presenting visual acuity, supporting the current practice of second eye surgery depending on the fellow eye's cataract status and visual acuity.
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Affiliation(s)
- Anna C S Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.
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Tan ACS, Wang JJ, Lamoureux EL, Wong W, Mitchell P, Li J, Tan AG, Wong TY. Cataract Prevalence Varies Substantially with Assessment Systems: Comparison of Clinical and Photographic Grading in a Population-Based Study. Ophthalmic Epidemiol 2011; 18:164-70. [DOI: 10.3109/09286586.2011.594205] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Narayanaswamy A, Su DH, Baskaran M, Tan ACS, Nongpiur ME, Htoon HM, Wong TY, Aung T. Comparison of ocular response analyzer parameters in chinese subjects with primary angle-closure and primary open-angle glaucoma. ACTA ACUST UNITED AC 2011; 129:429-34. [PMID: 21482869 DOI: 10.1001/archophthalmol.2011.60] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVES To evaluate corneal hysteresis (CH) and intraocular pressure (IOP) measured by the Ocular Response Analyzer in Chinese subjects with primary angle-closure glaucoma (PACG), assess their relationship with Goldmann applanation tonometry (GAT) measurements, and compare this with subjects with primary open-angle glaucoma (POAG) and normal controls. METHODS In this prospective observational study, consecutive subjects with PACG and POAG without prior intraocular surgery were enrolled from glaucoma clinics. Normal subjects were recruited from an ongoing population-based study. One eye of each subject underwent standardized ocular examination and IOP measurement by GAT and the Ocular Response Analyzer. Corneal hysteresis and corneal-compensated IOP were compared between groups. RESULTS Of the 443 subjects recruited, 131 had PACG, 162 had POAG, and 150 were normal. Corneal hysteresis was lower in PACG (9.1 mm Hg; 95% confidence interval [CI], 8.7 to 9.4 mm Hg) and POAG (9.5 mm Hg; 95% CI, 9.2 to 9.5 mm Hg) eyes compared with control eyes (10.4 mm Hg; 95% CI, 10.1 to 10.6 mm Hg; P < .001 for both), with no difference (P = .16) in CH found between PACG and POAG eyes. After adjusting for age, sex, and IOP measurement by GAT, CH persisted to be lower only in eyes with PACG in comparison with control eyes (9.4 vs 10.1 mm Hg; P = .006). Eyes with POAG had lower CH than control eyes but the difference was not statistically significant (9.6 vs 10.1 mm Hg; P = .06). CONCLUSIONS Corneal hysteresis was lower in eyes with glaucoma. After adjusting for age, sex, and IOP measurement by GAT, a persistently lower hysteresis was noted in eyes with PACG compared with other groups.
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Affiliation(s)
- Arun Narayanaswamy
- Glaucoma Service, Singapore National Eye Centre, 11 Third Hospital Ave, Singapore
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