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Hong J, Tan SS, Chua J. Optical coherence tomography angiography in glaucoma. Clin Exp Optom 2024; 107:110-121. [PMID: 38266148 DOI: 10.1080/08164622.2024.2306963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 01/11/2024] [Indexed: 01/26/2024] Open
Abstract
The use of optical coherence tomography angiography (OCTA) holds significant promise for optometrists in the diagnosis and management of glaucoma. It offers reliable differentiation of glaucomatous eyes from healthy ones and extends monitoring capabilities for advanced cases. OCTA represents a valuable addition to traditional assessment methods, particularly in complex cases. Glaucoma, a major cause of irreversible blindness, is traditionally diagnosed using structural and functional metrics. With growing interest, OCTA is being explored to diagnose, monitor, and manage glaucoma. This review focuses on the application of OCTA in glaucoma patients. A database search was carried out using Embase Elsevier (n = 664), PubMed (n = 574), and Cochrane Central Register of Controlled Trials (n = 19) on 15 August 2023. After deduplication and screening, 272 original papers were included in the narrative review. Inclusion criteria comprised English-language original studies on OCTA use in human glaucoma patients, with or without healthy controls. Exclusion criteria encompassed animal studies, in-vivo/in-vitro research, reviews, and congress abstracts. OCTA has good repeatability and reproducibility. OCTA metrics have good discriminatory power to differentiate glaucomatous eyes from healthy eyes and show strong associations with structural changes and visual field defects. OCTA can extend the monitoring of advanced glaucoma, addressing the 'floor effect' of traditional structural measurements. OCTA metrics can be affected by the choice of OCTA machine, post-image processing algorithms, systemic diseases, and ocular factors. Image artefacts can affect the accuracy of OCTA measurements, and proper scan quality evaluation is crucial to ensure reliable results. Additionally, artificial intelligence techniques offer promise for enhancing the diagnostic accuracy of OCTA by combining data from various retinal layers and regions. OCTA complements traditional methods in assessing glaucoma, especially in challenging cases, providing valuable insights for detection and management. Further research and clinical validation are needed to integrate OCTA into routine practice.
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Affiliation(s)
- Jimmy Hong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
| | - Shayne S Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
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Ma F, Wang S, Dai C, Qi F, Meng J. A new retinal OCT-angiography diabetic retinopathy dataset for segmentation and DR grading. JOURNAL OF BIOPHOTONICS 2023; 16:e202300052. [PMID: 37421596 DOI: 10.1002/jbio.202300052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 06/29/2023] [Accepted: 06/30/2023] [Indexed: 07/10/2023]
Abstract
PURPOSE Diabetic retinopathy (DR) is one of the most common diseases caused by diabetes and can lead to vision loss or even blindness. The wide-field optical coherence tomography (OCT) angiography is non-invasive imaging technology and convenient to diagnose DR. METHODS A newly constructed Retinal OCT-Angiography Diabetic retinopathy (ROAD) dataset is utilized for segmentation and grading tasks. It contains 1200 normal images, 1440 DR images, and 1440 ground truths for DR image segmentation. To handle the problem of grading DR, we propose a novel and effective framework, named projective map attention-based convolutional neural network (PACNet). RESULTS The experimental results demonstrate the effectiveness of our PACNet. The accuracy of the proposed framework for grading DR is 87.5% on the ROAD dataset. CONCLUSIONS The information on ROAD can be viewed at URL https://mip2019.github.io/ROAD. The ROAD dataset will be helpful for the development of the early detection of DR field and future research. TRANSLATIONAL RELEVANCE The novel framework for grading DR is a valuable research and clinical diagnosis method.
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Affiliation(s)
- Fei Ma
- Qufu Normal University, Rizhao, Shandong, China
| | | | - Cuixia Dai
- College Science, Shanghai Institute of Technology, Shanghai, China
| | - Fumin Qi
- National Supercomputing Center in Shenzhen, Shenzhen, Guangdong, China
| | - Jing Meng
- Qufu Normal University, Rizhao, Shandong, China
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3
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Chen R, Liu X, Yao M, Zou Z, Chen X, Li Z, Chen X, Su M, Lian H, Lu W, Yang Y, McAlinden C, Wang Q, Chen S, Huang J. Precision (repeatability and reproducibility) of papillary and peripapillary vascular density measurements using optical coherence tomography angiography in children. Front Med (Lausanne) 2023; 10:1037919. [PMID: 37035305 PMCID: PMC10076795 DOI: 10.3389/fmed.2023.1037919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 02/27/2023] [Indexed: 04/11/2023] Open
Abstract
Importance Optical coherence tomography angiography (OCTA) has been widely applied into children, however, few studies have assessed the repeatability and reproducibility of papillary and peripapillary VD in healthy children. Objective To assess the precision of papillary and peripapillary vascular density (VD) measurements using optical coherence tomography angiography (OCTA) and analyze the effects of the signal strength index (SSI) and axial length (AL) on precision estimates. Design setting and participants This was a prospective observational study. Seventy-eight children aged 6-16 years underwent 4.5 × 4.5 mm OCTA (RTVue XR Avanti) disc scans: two scans by one examiner (repeatability) and two additional scans by another examiner (reproducibility). Within-subject standard deviation (Sw), test-retest reproducibility (TRT), within-subject coefficient of variation (CoV), intraclass correlation coefficient (ICC), and Bland-Altman analysis were performed. Main outcomes and measures In repeatability measurement, the fluctuation ranges (minimum to maximum) of VD between intraexaminer A/B in Sw, TRT, CoV, and ICC were (1.05-2.17)% / (1.16-2.32)%, (2.9-6)% / (3.21-6.44)%, (1.9-4.47)% / (2.08-5)%, and (0.588-0.783)% / (0.633-0.803)%, respectively. In reproducibility measurement, the fluctuation ranges of VD in Sw, TRT, CoV, and ICC were 1.11-2.13%, 3.07-5.91%, 1.99-4.41%, and 0.644-0.777%, respectively. VD was negatively correlated with SSI in most sectors of the peripapillary (e.g., inferior nasal, temporal inferior, temporal superior, superior temporal, and superior nasal). AL was positively correlated with inferior temporal VD and negatively correlated with superior nasal VD. Conclusion and relevance Optical coherence tomography angiography showed moderate-to-good repeatability and reproducibility for papillary and peripapillary perfusion measurements in healthy children. The SSI value affects most of the peripapillary VD, while AL affects only the temporal inferior and nasal superior peripapillary VD.
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Affiliation(s)
- Ruru Chen
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xinyu Liu
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Mingyu Yao
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zhilin Zou
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xinyi Chen
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zheng Li
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xin Chen
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Mengjuan Su
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Hengli Lian
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Weiwei Lu
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yizhou Yang
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Colm McAlinden
- Department of Ophthalmology, Eye Institute, Eye and ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Department of Ophthalmology, Singleton Hospital, Swansea Bay University Health Board, Swansea, United Kingdom
- Department of Ophthalmology, Royal Gwent Hospital, Aneurin Bevan University Health Board, Newport, United Kingdom
| | - Qinmei Wang
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- *Correspondence: Qinmei Wang,
| | - Shihao Chen
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- Shihao Chen,
| | - Jinhai Huang
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- Department of Ophthalmology, Eye Institute, Eye and ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
- Jinhai Huang,
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Lun K, Sim YC, Chong R, Wong D, Tan B, Husain R, Aung T, Sng CCA, Schmetterer L, Chua J. Investigating the macular choriocapillaris in early primary open-angle glaucoma using swept-source optical coherence tomography angiography. Front Med (Lausanne) 2022; 9:999167. [PMID: 36213634 PMCID: PMC9532514 DOI: 10.3389/fmed.2022.999167] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 09/05/2022] [Indexed: 11/23/2022] Open
Abstract
Introduction There has been a growing interest in the role of vascular factors in glaucoma. Studies have looked at the characteristics of macular choriocapillaris in patients with glaucoma but with conflicting results. Our study aims to use swept-source optical coherence tomography angiography (SS-OCTA) to evaluate macular choriocapillaris metrics in normal participants and compare them with patients with early primary open-angle glaucoma (POAG) (mean deviation better than −6dB). Methods In this prospective, observational, cross-sectional study, 104 normal controls (157 eyes) and 100 patients with POAG (144 eyes) underwent 3 mm × 3mm imaging of the macula using the Plex Elite 9000 (Zeiss Meditec, Dublin, CA, USA). Choriocapillaris OCTA images were extracted from the device’s built-in review software and were subsequently evaluated for the density and size of choriocapillaris flow deficits. Results After adjusting for confounding factors, the density of flow deficits was independently higher in those aged 53 years and above (P ≤ 0.024) whereas the average flow deficit size was significantly larger in those aged 69 years and above (95% CI = 12.39 to 72.91; P = 0.006) in both normal and POAG patients. There were no significant differences in the density of flow deficits (P = 0.453) and average flow deficit size (P = 0.637) between normal and POAG participants. Conclusion Our study found that macular choriocapillaris microvasculature on SS-OCTA is unaltered by subjects with POAG. This suggests that OCTA macular choriocapillaris may not be potentially helpful in differentiating early glaucoma from healthy eyes.
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Affiliation(s)
- Katherine Lun
- Department of Ophthalmology, National University Health System, Singapore, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Yin Ci Sim
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
| | - Rachel Chong
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Ophthalmology & Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Damon Wong
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Bingyao Tan
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
| | - Rahat Husain
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
| | - Tin Aung
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Ophthalmology & Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Chelvin C. A. Sng
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
| | - Leopold Schmetterer
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Ophthalmology & Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
| | - Jacqueline Chua
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Ophthalmology & Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- *Correspondence: Jacqueline Chua,
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Jiang H, Simms AG, Sadaghiani S, Jiang YY, Morgan JIW, Aguirre GK, Pattany PM, Detre JA, Wang J. Multi-Center Repeatability of Macular Capillary Perfusion Density Using Optical Coherence Tomography Angiography. Clin Ophthalmol 2022; 16:3069-3078. [PMID: 36160730 PMCID: PMC9491369 DOI: 10.2147/opth.s383770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 09/06/2022] [Indexed: 02/03/2023] Open
Abstract
Background/Aims This study was to determine the test-retest repeatability in quantifying macular capillary perfusion density (CPD, expressed as fractal dimension) using optical coherence tomography angiography (OCTA) in a multi-center setting. Methods OCTA data were obtained in self-reported healthy subjects from Bascom Palmer Eye Institute at the University of Miami (UM, N = 18) and the University of Pennsylvania (UPenn, N = 22). The right eye of each subject was imaged twice at the first visit and then again at an interval of one week to assess intra-visit and inter-visit repeatability. The macular area of the OCTA-derived capillary perfusion density (OCTA-CPD) was analyzed by custom-made image processing and fractal analysis software. Fractal analysis was performed on the skeletonized microvascular network to yield OCTA-CPD by box-counting to the fractal dimension (Dbox) in the superficial vascular plexus (SVP). Repeatability was assessed by three measures: within-subject standard deviation (Sw), coefficient of variation (CoV) of repeated measures, and intraclass correlation coefficient (ICC). Results OCTA-CPD from both sites (UM and UPENN) showed good to excellent intra-visit repeatability, as demonstrated by the Sw ≤0.004, CoVs ≤0.23%, and ICCs ≥0.61. Similarly, both sites had good to excellent inter-visit repeatability, as shown by the Sw ≤0.005, CoVs ≤0.28%, and ICCs ≥0.61. The Bland-Altman plots of the intra-visit and inter-visit measurements showed excellent agreements between the paired measurements with minimal biases. Conclusion Our data showed that comparable high repeatability of OCTA-CPD can be achieved in both research sites using the same device, scan protocol, and image analysis.
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Affiliation(s)
- Hong Jiang
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA,Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Ava-Gaye Simms
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Shokufeh Sadaghiani
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Yu You Jiang
- Scheie Eye Institute and Center for Advanced Retinal and Ocular Therapeutics, Department of Ophthalmology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Jessica I W Morgan
- Scheie Eye Institute and Center for Advanced Retinal and Ocular Therapeutics, Department of Ophthalmology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Geoffrey K Aguirre
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Pradip M Pattany
- Department of Radiology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - John A Detre
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jianhua Wang
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA,Correspondence: Jianhua Wang, Bascom Palmer Eye Institute, University of Miami, Miller School of Medicine, 1638 NW 10th Avenue, McKnight Building - Room 202A, Miami, FL, 33136, USA, Tel +1 305 482-5010, Fax +1 305 482-5012, Email
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Hao H, Xu C, Zhang D, Yan Q, Zhang J, Liu Y, Zhao Y. Sparse-based Domain Adaptation Network for OCTA Image Super-Resolution Reconstruction. IEEE J Biomed Health Inform 2022; 26:4402-4413. [PMID: 35895639 DOI: 10.1109/jbhi.2022.3194025] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Retinal Optical Coherence Tomography Angiography (OCTA) with high-resolution is important for the quantification and analysis of retinal vasculature. However, the resolution of OCTA images is inversely proportional to the field of view at the same sampling frequency, which is not conducive to clinicians for analyzing larger vascular areas. In this paper, we propose a novel Sparse-based domain Adaptation Super-Resolution network (SASR) for the reconstruction of realistic [Formula: see text]/low-resolution (LR) OCTA images to high-resolution (HR) representations. To be more specific, we first perform a simple degradation of the [Formula: see text]/high-resolution (HR) image to obtain the synthetic LR image. An efficient registration method is then employed to register the synthetic LR with its corresponding [Formula: see text] image region within the [Formula: see text] image to obtain the cropped realistic LR image. We then propose a multi-level super-resolution model for the fully-supervised reconstruction of the synthetic data, guiding the reconstruction of the realistic LR images through a generative-adversarial strategy that allows the synthetic and realistic LR images to be unified in the feature domain. Finally, a novel sparse edge-aware loss is designed to dynamically optimize the vessel edge structure. Extensive experiments on two OCTA sets have shown that our method performs better than state-of-the-art super-resolution reconstruction methods. In addition, we have investigated the performance of the reconstruction results on retina structure segmentations, which further validate the effectiveness of our approach.
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Arnould L, Haddad D, Baudin F, Gabrielle PH, Sarossy M, Bron AM, Aliahmad B, Creuzot-Garcher C. Repeatability and Reproducibility of Retinal Fractal Dimension Measured with Swept-Source Optical Coherence Tomography Angiography in Healthy Eyes: A Proof-of-Concept Study. Diagnostics (Basel) 2022; 12:diagnostics12071769. [PMID: 35885673 PMCID: PMC9323583 DOI: 10.3390/diagnostics12071769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 07/11/2022] [Accepted: 07/18/2022] [Indexed: 11/16/2022] Open
Abstract
The retinal vascular network fractal dimension (FD) could be a promising imaging biomarker. Our objective was to evaluate its repeatability and reproducibility in healthy eyes. A cross-sectional study was undertaken with young, healthy volunteers who had no reported cardiac risk factors or ocular disease history. For each participant, three SS-OCTA images (12 × 12 mm) were acquired using the Plex Elite 9000 (Carl Zeiss Meditec AG, Jena, Germany) by two ophthalmologists. Automated segmentation was obtained from both the superficial and deep capillary plexuses. FD was estimated by box counting. The intraclass correlation coefficients (ICC) were used as measures for repeatability and reproducibility. A total of 43 eyes of healthy volunteers were included. The mean ± standard deviation (SD) age was 30 ± 6.2 years. The results show good repeatability. The ICC was 0.722 (95% CI, 0.541–0.839) in the superficial capillary plexus and 0.828 (95% CI, 0.705–0.903) in the deep capillary plexus. For reproducibility, the ICC was 0.651 (95% CI, 0.439–0.795) and 0.363 (95% CI, 0.073–0.596) at the superficial and deep capillary plexus, respectively. In this study, the FD of the vascular network measured via SS-OCTA showed good repeatability and reproducibility in healthy participants.
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Affiliation(s)
- Louis Arnould
- Ophthalmology Department, Dijon University Hospital, 21000 Dijon, France; (D.H.); (F.B.); (P.-H.G.); (A.M.B.); (C.C.-G.)
- INSERM, CIC1432, Clinical Investigation Center, Clinical Epidemiology/Clinical Trials Unit, Dijon University Hospital, 21000 Dijon, France
- Taste and Food Science Centre, AgroSup Dijon, CNRS, INRAE, Bourgogne Franche-Comté University, 21000 Dijon, France
- Correspondence: ; Tel.: +33-380-293-536; Fax: +33-380-293-879
| | - Déa Haddad
- Ophthalmology Department, Dijon University Hospital, 21000 Dijon, France; (D.H.); (F.B.); (P.-H.G.); (A.M.B.); (C.C.-G.)
| | - Florian Baudin
- Ophthalmology Department, Dijon University Hospital, 21000 Dijon, France; (D.H.); (F.B.); (P.-H.G.); (A.M.B.); (C.C.-G.)
- INSERM, CIC1432, Clinical Investigation Center, Clinical Epidemiology/Clinical Trials Unit, Dijon University Hospital, 21000 Dijon, France
- EA7460, PEC2, Cerebral and Cardiovascular Epidemiology and Physiopathology, 21000 Dijon, France
| | - Pierre-Henry Gabrielle
- Ophthalmology Department, Dijon University Hospital, 21000 Dijon, France; (D.H.); (F.B.); (P.-H.G.); (A.M.B.); (C.C.-G.)
- Taste and Food Science Centre, AgroSup Dijon, CNRS, INRAE, Bourgogne Franche-Comté University, 21000 Dijon, France
| | - Marc Sarossy
- School of Engineering, RMIT University, Melbourne, VIC 3000, Australia; (M.S.); (B.A.)
| | - Alain M. Bron
- Ophthalmology Department, Dijon University Hospital, 21000 Dijon, France; (D.H.); (F.B.); (P.-H.G.); (A.M.B.); (C.C.-G.)
- Taste and Food Science Centre, AgroSup Dijon, CNRS, INRAE, Bourgogne Franche-Comté University, 21000 Dijon, France
| | - Behzad Aliahmad
- School of Engineering, RMIT University, Melbourne, VIC 3000, Australia; (M.S.); (B.A.)
| | - Catherine Creuzot-Garcher
- Ophthalmology Department, Dijon University Hospital, 21000 Dijon, France; (D.H.); (F.B.); (P.-H.G.); (A.M.B.); (C.C.-G.)
- Taste and Food Science Centre, AgroSup Dijon, CNRS, INRAE, Bourgogne Franche-Comté University, 21000 Dijon, France
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A multi-branch convolutional neural network for screening and staging of diabetic retinopathy based on wide-field optical coherence tomography angiography. Ing Rech Biomed 2022. [DOI: 10.1016/j.irbm.2022.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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9
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Sampson DM, Dubis AM, Chen FK, Zawadzki RJ, Sampson DD. Towards standardizing retinal optical coherence tomography angiography: a review. LIGHT, SCIENCE & APPLICATIONS 2022; 11:63. [PMID: 35304441 PMCID: PMC8933532 DOI: 10.1038/s41377-022-00740-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 02/01/2022] [Accepted: 02/14/2022] [Indexed: 05/11/2023]
Abstract
The visualization and assessment of retinal microvasculature are important in the study, diagnosis, monitoring, and guidance of treatment of ocular and systemic diseases. With the introduction of optical coherence tomography angiography (OCTA), it has become possible to visualize the retinal microvasculature volumetrically and without a contrast agent. Many lab-based and commercial clinical instruments, imaging protocols and data analysis methods and metrics, have been applied, often inconsistently, resulting in a confusing picture that represents a major barrier to progress in applying OCTA to reduce the burden of disease. Open data and software sharing, and cross-comparison and pooling of data from different studies are rare. These inabilities have impeded building the large databases of annotated OCTA images of healthy and diseased retinas that are necessary to study and define characteristics of specific conditions. This paper addresses the steps needed to standardize OCTA imaging of the human retina to address these limitations. Through review of the OCTA literature, we identify issues and inconsistencies and propose minimum standards for imaging protocols, data analysis methods, metrics, reporting of findings, and clinical practice and, where this is not possible, we identify areas that require further investigation. We hope that this paper will encourage the unification of imaging protocols in OCTA, promote transparency in the process of data collection, analysis, and reporting, and facilitate increasing the impact of OCTA on retinal healthcare delivery and life science investigations.
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Affiliation(s)
- Danuta M Sampson
- Surrey Biophotonics, Centre for Vision, Speech and Signal Processing and School of Biosciences and Medicine, The University of Surrey, Guildford, GU2 7XH, UK.
| | - Adam M Dubis
- NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Trust and UCL Institute of Ophthalmology, London, EC1V 2PD, UK
| | - Fred K Chen
- Centre for Ophthalmology and Visual Science (incorporating Lions Eye Institute), The University of Western Australia, Nedlands, Western Australia, 6009, Australia
- Department of Ophthalmology, Royal Perth Hospital, Perth, Western Australia, 6000, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, 3002, Australia
| | - Robert J Zawadzki
- Department of Ophthalmology & Vision Science, University of California Davis, Sacramento, CA, 95817, USA
| | - David D Sampson
- Surrey Biophotonics, Advanced Technology Institute, School of Physics and School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, GU2 7XH, UK
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10
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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. BIOMEDICAL OPTICS 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] [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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11
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Wong D, Chua J, Lin E, Tan B, Yao X, Chong R, Sng C, Lau A, Husain R, Aung T, Schmetterer L. Focal Structure-Function Relationships in Primary Open-Angle Glaucoma Using OCT and OCT-A Measurements. Invest Ophthalmol Vis Sci 2021; 61:33. [PMID: 33372979 PMCID: PMC7774057 DOI: 10.1167/iovs.61.14.33] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To evaluate the focal structure-function associations among visual field (VF) loss, optical coherence tomography angiography (OCT-A) vascular measurements, and optical coherence tomography (OCT) structural measurements in glaucoma. Methods In this cross-sectional study, subjects underwent standard automated perimetry, OCT-based nerve fiber thickness measurements, and OCT-A imaging. Mappings of focal VF test locations with OCT and OCT-A measurements were defined using anatomically adjusted nerve fiber trajectories and were studied using multivariate mixed-effects analysis. Segmented regression analysis was used to determine the presence of breakpoints in the structure-function associations. Results The study included 119 eyes from 86 Chinese subjects with primary open-angle glaucoma (POAG). VF mean deviation was significantly associated with global capillary perfusion density (β = 0.13 ± 0.08) and global retinal nerve fiber layer thickness (β = 0.09 ± 0.02). Focal capillary density (FCD) was significantly associated with VF losses at 34 VF test locations (66.7% of 24-2 VF), with 24 of the 34 locations being within 20° of retinal eccentricity. Focal nerve layer (FNL) thickness was significantly associated with 16 VF test locations (31.4% of 24-2 VF; eight locations within 20° eccentricity). For VF test locations in the central 10° VF, VF losses below the breakpoint were significantly associated with FCD (slope, 0.89 ± 0.12, P < 0.001), but not with FNL thickness (slope, 0.57 ± 0.39, P = 0.15). Conclusions Focal capillary densities were significantly associated with a wider range of visual field losses and in a larger proportion of the visual field compared to nerve fiber thickness.
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Affiliation(s)
- Damon Wong
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore.,NTU Institute of Health Technologies, Singapore.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.,Academic Clinical Program, Duke-NUS Medical School, Singapore
| | - Emily Lin
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Bingyao Tan
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore.,NTU Institute of Health Technologies, Singapore.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Xinwen Yao
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore.,NTU Institute of Health Technologies, Singapore.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Rachel Chong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Chelvin Sng
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.,Ophthalmology Department, National University Hospital, Singapore
| | - Amanda Lau
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Rahat Husain
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Tin Aung
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.,Academic Clinical Program, Duke-NUS Medical School, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Leopold Schmetterer
- SERI-NTU Advanced Ocular Engineering (STANCE), 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, Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
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12
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Choriocapillaris microvasculature dysfunction in systemic hypertension. Sci Rep 2021; 11:4603. [PMID: 33633311 PMCID: PMC7907127 DOI: 10.1038/s41598-021-84136-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 02/11/2021] [Indexed: 12/13/2022] Open
Abstract
We examined the choriocapillaris microvasculature using a non-invasive swept-source optical coherence tomography angiography (SS-OCTA) in 41 healthy controls and 71 hypertensive patients and determined possible correlations with BP and renal parameters. BP levels, serum creatinine and urine microalbumin/creatinine ratio (MCR) specimens were collected. The estimated glomerular filtration rate (eGFR) was calculated based on CKD-EPI Creatinine Equation. The main outcome was choriocapillaris flow deficits (CFD) metrics (density, size and numbers). The CFD occupied a larger area and were fewer in number in the hypertensive patients with poor BP control (407 ± 10 µm2; 3260 ± 61) compared to the hypertensives with good BP control (369 ± 5 µm2; 3551 ± 41) and healthy controls (365 ± 11 µm2; 3581 ± 84). Higher systolic BP (β = 9.90, 95% CI, 2.86–16.93), lower eGFR (β = − 0.85; 95% CI, − 1.58 to − 0.13) and higher urine MCR (β = 1.53, 95% CI, 0.32–2.78) were associated with larger areas of CFD. Similar significant associations with systolic BP, eGFR and urine MCR were found with number of CFD. These findings highlight the potential role of choriocapillaris imaging using SS-OCTA as an indicator of systemic microvascular abnormalities secondary to hypertensive disease.
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13
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Effect of vessel enhancement filters on the repeatability of measurements obtained from widefield swept-source optical coherence tomography angiography. Sci Rep 2020; 10:22179. [PMID: 33335182 PMCID: PMC7746686 DOI: 10.1038/s41598-020-79281-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 11/26/2020] [Indexed: 12/13/2022] Open
Abstract
We assessed the inter-visit repeatability of 15 × 9-mm2 swept-source OCTA (SS-OCTA; PLEX Elite 9000, Carl Zeiss Meditec) metrics in 14 healthy participants. We analysed the perfusion density (PD) of large vessels, superficial capillary plexus (SCP), and deep capillary plexus (DCP) as well as choriocapillaris flow voids in 2 different regions: the macular region and peripheral region. Also, retinal plexus metrics were processed further using different filters (Hessian, Gabor and Bayesian) while choriocapillaris flow voids were calculated with 1 and 1.25 standard deviation (SD) thresholding algorithms. We found excellent repeatability in the perfusion densities of large vessels (ICC > 0.96). Perfusion densities varied with different filters in the macular region (SCP: 24.12–38.57% and DCP: 25.16–38.50%) and peripheral (SCP: 30.52–39.84% and DCP: 34.19–41.60%) regions. The ICCs were lower in the macular region compared to the peripheral region and lower for DCP than for SCP. For choriocapillaris flow voids, the 1.25 SD threshold resulted in fewer flow voids, while a good ICC (ICC > 0.81) was achieved using either threshold settings for flow void features in both regions. Our results suggest good repeatability of widefield SS-OCTA for the measurements of retinal perfusion density and choriocapillaris flow voids, but measurements from different filters should not be interchanged.
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14
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Tan B, Sim R, Chua J, Wong DWK, Yao X, Garhöfer G, Schmidl D, Werkmeister RM, Schmetterer L. Approaches to quantify optical coherence tomography angiography metrics. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:1205. [PMID: 33241054 PMCID: PMC7576021 DOI: 10.21037/atm-20-3246] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Optical coherence tomography (OCT) has revolutionized the field of ophthalmology in the last three decades. As an OCT extension, OCT angiography (OCTA) utilizes a fast OCT system to detect motion contrast in ocular tissue and provides a three-dimensional representation of the ocular vasculature in a non-invasive, dye-free manner. The first OCT machine equipped with OCTA function was approved by U.S. Food and Drug Administration in 2016 and now it is widely applied in clinics. To date, numerous methods have been developed to aid OCTA interpretation and quantification. In this review, we focused on the workflow of OCTA-based interpretation, beginning from the generation of the OCTA images using signal decorrelation, which we divided into intensity-based, phase-based and phasor-based methods. We further discussed methods used to address image artifacts that are commonly observed in clinical settings, to the algorithms for image enhancement, binarization, and OCTA metrics extraction. We believe a better grasp of these technical aspects of OCTA will enhance the understanding of the technology and its potential application in disease diagnosis and management. Moreover, future studies will also explore the use of ocular OCTA as a window to link ocular vasculature to the function of other organs such as the kidney and brain.
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Affiliation(s)
- Bingyao Tan
- Institute for Health Technologies, Nanyang Technological University, Singapore, Singapore.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE) Program, Nanyang Technological University, Singapore, Singapore
| | - Ralene Sim
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Damon W K Wong
- Institute for Health Technologies, Nanyang Technological University, Singapore, Singapore.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE) Program, Nanyang Technological University, Singapore, Singapore
| | - Xinwen Yao
- Institute for Health Technologies, Nanyang Technological University, Singapore, Singapore.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE) Program, Nanyang Technological University, Singapore, Singapore
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - René M Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE) Program, Nanyang Technological University, Singapore, Singapore.,Academic Clinical Program, Duke-NUS 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.,Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.,Department of Ophthalmology, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
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15
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Chua J, Schmetterer L. Letter to the Editor on 'Retinal microvascular attenuation in mental cognitive impairment and Alzheimer's disease by optical coherence tomography angiography'. Acta Ophthalmol 2020; 98:e793-e794. [PMID: 32421221 DOI: 10.1111/aos.14464] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 04/19/2020] [Indexed: 01/14/2023]
Affiliation(s)
- Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,Department of Ophthalmology, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, Austria.,Institute of Ophthalmology, Basel, Switzerland
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16
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Lin E, Ke M, Tan B, Yao X, Wong D, Ong L, Schmetterer L, Chua J. Are choriocapillaris flow void features robust to diurnal variations? A swept-source optical coherence tomography angiography (OCTA) study. Sci Rep 2020; 10:11249. [PMID: 32647298 PMCID: PMC7347889 DOI: 10.1038/s41598-020-68204-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Accepted: 06/02/2020] [Indexed: 12/17/2022] Open
Abstract
We evaluated the impact of diurnal variation on choroidal and retinal microvasculature and structural measurements using a swept-source optical coherence tomography angiography machine (SS-OCTA; PLEX Elite 9,000, Carl Zeiss Meditec, Inc., Dublin, USA). Fourteen participants who were without ocular diseases underwent SS-OCTA imaging using 3 × 3-mm2 macular scan pattern on two separate days at five time points. Choriocapillaris flow voids were generated to determine its density (percentage), size (μm) and numbers. Perfusion densities of the large superficial vessels, as well as capillaries on superficial and deep vascular plexuses were generated from retinal angiograms. Subfoveal choroidal and retinal thicknesses were manually measured. Repeated-measures ANOVA was used to investigate the impact of diurnal variation on choroidal and retinal measurements. There was no observable diurnal pattern for any of the flow void features, in terms of the density, size and numbers. There was a significant diurnal pattern observed in the choroidal thickness, where it decreased progressively during the day (P < 0.005). As opposed to sub-foveal choroidal thickness, there does not appear to be significant diurnal variation in choriocapillaris flow voids in normal individuals. This suggests that alterations of choriocapillaris flow deficit seen in pathological eyes will not be confounded by the diurnal fluctuation.
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Affiliation(s)
- Emily Lin
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore
| | - Mengyuan Ke
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,Institute for Health Technologies, Nanyang Technological University, Singapore, Singapore
| | - Xinwen Yao
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,Institute for Health Technologies, Nanyang Technological University, Singapore, Singapore
| | - Damon Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,Institute for Health Technologies, Nanyang Technological University, Singapore, Singapore
| | - Lirong Ong
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,Institute for Health Technologies, Nanyang Technological University, Singapore, Singapore.,Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, Austria.,Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore. .,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore. .,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore.
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17
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Chua J, Sim R, Tan B, Wong D, Yao X, Liu X, Ting DSW, Schmidl D, Ang M, Garhöfer G, Schmetterer L. Optical Coherence Tomography Angiography in Diabetes and Diabetic Retinopathy. J Clin Med 2020; 9:E1723. [PMID: 32503234 PMCID: PMC7357089 DOI: 10.3390/jcm9061723] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 05/24/2020] [Accepted: 06/02/2020] [Indexed: 12/21/2022] Open
Abstract
Diabetic retinopathy (DR) is a common complication of diabetes mellitus that disrupts the retinal microvasculature and is a leading cause of vision loss globally. Recently, optical coherence tomography angiography (OCTA) has been developed to image the retinal microvasculature, by generating 3-dimensional images based on the motion contrast of circulating blood cells. OCTA offers numerous benefits over traditional fluorescein angiography in visualizing the retinal vasculature in that it is non-invasive and safer; while its depth-resolved ability makes it possible to visualize the finer capillaries of the retinal capillary plexuses and choriocapillaris. High-quality OCTA images have also enabled the visualization of features associated with DR, including microaneurysms and neovascularization and the quantification of alterations in retinal capillary and choriocapillaris, thereby suggesting a promising role for OCTA as an objective technology for accurate DR classification. Of interest is the potential of OCTA to examine the effect of DR on individual retinal layers, and to detect DR even before it is clinically detectable on fundus examination. We will focus the review on the clinical applicability of OCTA derived quantitative metrics that appear to be clinically relevant to the diagnosis, classification, and management of patients with diabetes or DR. Future studies with longitudinal design of multiethnic multicenter populations, as well as the inclusion of pertinent systemic information that may affect vascular changes, will improve our understanding on the benefit of OCTA biomarkers in the detection and progression of DR.
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Affiliation(s)
- Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
| | - Ralene Sim
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
- Institute of Health Technologies, Nanyang Technological University, Singapore 639798, Singapore
| | - Damon Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
- Institute of Health Technologies, Nanyang Technological University, Singapore 639798, Singapore
| | - Xinwen Yao
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
- Institute of Health Technologies, Nanyang Technological University, Singapore 639798, Singapore
| | - Xinyu Liu
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
| | - Daniel S. W. Ting
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (D.S.); (G.G.)
| | - Marcus Ang
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (D.S.); (G.G.)
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
- Institute of Health Technologies, Nanyang Technological University, Singapore 639798, Singapore
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (D.S.); (G.G.)
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, 1090 Vienna, Austria
- Institute of Molecular and Clinical Ophthalmology, CH-4031 Basel, Switzerland
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18
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Yao X, Ke M, Ho Y, Lin E, Wong DWK, Tan B, Schmetterer L, Chua J. Comparison of retinal vessel diameter measurements from swept-source OCT angiography and adaptive optics ophthalmoscope. Br J Ophthalmol 2020; 105:426-431. [PMID: 32461263 PMCID: PMC7907556 DOI: 10.1136/bjophthalmol-2020-316111] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/14/2020] [Accepted: 05/01/2020] [Indexed: 11/04/2022]
Abstract
BACKGROUND/IMS To compare the retinal vessel diameter measurements obtained from the swept-source optical coherence tomography angiography (OCTA; Plex Elite 9000, Carl Zeiss Meditec, USA) and adaptive optics ophthalmoscope (AOO; RTX1, Imagine Eyes, France). METHODS Fifteen healthy subjects, 67% women, mean age (SD) 30.87 (6.19) years, were imaged using OCTA and AOO by a single experienced operator on the same day. Each eye was scanned using two OCTA protocols (3×3 mm2 and 9×9 mm2) and two to five AOO scans (1.2×1.2 mm2). The OCTA and AOO scans were scaled to the same pixel resolution. Two independent graders measured the vessel diameter at the same location on the region-of-interest in the three coregistered scans. Differences in vessel diameter measurements between the scans were assessed. RESULTS The inter-rater agreement was excellent for vessel diameter measurement in both OCTA protocols (ICC=0.92) and AOO (ICC=0.98). The measured vessel diameter was widest from the OCTA 3×3 mm2 (55.2±16.3 µm), followed by OCTA 9×9 mm2 (54.7±14.3 µm) and narrowest by the AOO (50.5±15.6 µm; p<0.001). Measurements obtained from both OCTA protocols were significantly wider than the AOO scan (OCTA 3×3 mm2: mean difference Δ=4.7 µm, p<0.001; OCTA 9×9 mm2: Δ=4.2 µm, p<0.001). For vessels >45 µm, it appeared to be larger in OCTA 3×3 mm2 scan than the 9×9 mm2 scan (Δ=1.9 µm; p=0.005), while vessels <45 µm appeared smaller in OCTA 3×3 mm2 scan (Δ=-1.3 µm; p=0.009) CONCLUSIONS: The diameter of retinal vessels measured from OCTA scans were generally wider than that obtained from AOO scans. Different OCTA scan protocols may affect the vessel diameter measurements. This needs to be considered when OCTA measures such as vessel density are calculated.
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Affiliation(s)
- Xinwen Yao
- Institute of Health Technologies, Nanyang Technological University, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore.,Singapore Eye Research Institute, Singapore National Eye Center, Singapore
| | - Mengyuan Ke
- Singapore Eye Research Institute, Singapore National Eye Center, Singapore
| | - Yijie Ho
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Emily Lin
- Singapore Eye Research Institute, Singapore National Eye Center, Singapore
| | - Damon W K Wong
- Institute of Health Technologies, Nanyang Technological University, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore.,Singapore Eye Research Institute, Singapore National Eye Center, Singapore
| | - Bingyao Tan
- Institute of Health Technologies, Nanyang Technological University, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore.,Singapore Eye Research Institute, Singapore National Eye Center, Singapore
| | - Leopold Schmetterer
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore.,Singapore Eye Research Institute, Singapore National Eye Center, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore.,Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Academic Clinical Program, Duke-NUS Medical School, Singapore.,Institute of Ophthalmology, Basel, Switzerland
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Center, Singapore .,Academic Clinical Program, Duke-NUS Medical School, Singapore
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