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Chua J, Tan B, Wong D, Garhöfer G, Liew XW, Popa-Cherecheanu A, Loong Chin CW, Milea D, Li-Hsian Chen C, Schmetterer L. Optical coherence tomography angiography of the retina and choroid in systemic diseases. Prog Retin Eye Res 2024; 103:101292. [PMID: 39218142 DOI: 10.1016/j.preteyeres.2024.101292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 08/27/2024] [Accepted: 08/28/2024] [Indexed: 09/04/2024]
Abstract
Optical coherence tomography angiography (OCTA) has transformed ocular vascular imaging, revealing microvascular changes linked to various systemic diseases. This review explores its applications in diabetes, hypertension, cardiovascular diseases, and neurodegenerative diseases. While OCTA provides a valuable window into the body's microvasculature, interpreting the findings can be complex. Additionally, challenges exist due to the relative non-specificity of its findings where changes observed in OCTA might not be unique to a specific disease, variations between OCTA machines, the lack of a standardized normative database for comparison, and potential image artifacts. Despite these limitations, OCTA holds immense potential for the future. The review highlights promising advancements like quantitative analysis of OCTA images, integration of artificial intelligence for faster and more accurate interpretation, and multi-modal imaging combining OCTA with other techniques for a more comprehensive characterization of the ocular vasculature. Furthermore, OCTA's potential future role in personalized medicine, enabling tailored treatment plans based on individual OCTA findings, community screening programs for early disease detection, and longitudinal studies tracking disease progression over time is also discussed. In conclusion, OCTA presents a significant opportunity to improve our understanding and management of systemic diseases. Addressing current limitations and pursuing these exciting future directions can solidify OCTA as an indispensable tool for diagnosis, monitoring disease progression, and potentially guiding treatment decisions across various systemic health conditions.
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Affiliation(s)
- Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
| | - Damon Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore; SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore; School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore; Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria
| | - Xin Wei Liew
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Alina Popa-Cherecheanu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; Emergency University Hospital, Department of Ophthalmology, Bucharest, Romania
| | - Calvin Woon Loong Chin
- Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore; National Heart Research Institute Singapore, National Heart Centre Singapore, Singapore
| | - Dan Milea
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Fondation Ophtalmologique Adolphe De Rothschild, Paris, France
| | - Christopher Li-Hsian Chen
- Memory Aging and Cognition Centre, Departments of Pharmacology and Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore; SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore; School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore; Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland; Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria; Fondation Ophtalmologique Adolphe De Rothschild, Paris, France; Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, Austria.
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Tillmann A, Turgut F, Munk MR. Optical coherence tomography angiography in neovascular age-related macular degeneration: comprehensive review of advancements and future perspective. Eye (Lond) 2024:10.1038/s41433-024-03295-8. [PMID: 39147864 DOI: 10.1038/s41433-024-03295-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 06/09/2024] [Accepted: 08/05/2024] [Indexed: 08/17/2024] Open
Abstract
Optical coherence tomography angiography (OCTA) holds promise in enhancing the care of various retinal vascular diseases, including neovascular age-related macular degeneration (nAMD). Given nAMD's vascular nature and the distinct vasculature of macular neovascularization (MNV), detailed analysis is expected to gain significance. Research in artificial intelligence (AI) indicates that en-face OCTA views may offer superior predictive capabilities than spectral domain optical coherence tomography (SD-OCT) images, highlighting the necessity to identify key vascular parameters. Analyzing vasculature could facilitate distinguishing MNV subtypes and refining diagnosis. Future studies correlating OCTA parameters with clinical data might prompt a revised classification system. However, the combined utilization of qualitative and quantitative OCTA biomarkers to enhance the accuracy of diagnosing disease activity remains underdeveloped. Discrepancies persist regarding the optimal biomarker for indicating an active lesion, warranting comprehensive prospective studies for validation. AI holds potential in extracting valuable insights from the vast datasets within OCTA, enabling researchers and clinicians to fully exploit its OCTA imaging capabilities. Nevertheless, challenges pertaining to data quantity and quality pose significant obstacles to AI advancement in this field. As OCTA gains traction in clinical practice and data volume increases, AI-driven analysis is expected to further augment diagnostic capabilities.
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Affiliation(s)
- Anne Tillmann
- Augenarzt Praxisgemeinschaft Gutblick, Pfäffikon, Switzerland
| | - Ferhat Turgut
- Augenarzt Praxisgemeinschaft Gutblick, Pfäffikon, Switzerland
- Department of Ophthalmology, Stadtspital Zürich, Zürich, Switzerland
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary
| | - Marion R Munk
- Augenarzt Praxisgemeinschaft Gutblick, Pfäffikon, Switzerland.
- Department of Ophthalmology, Inselspital, Bern University Hospital, University of Bern, 3010, Bern, Switzerland.
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60208, USA.
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Chen A, Wei P, Wang J, Liu L, Camino A, Guo Y, Tan O, Jia Y, Huang D. Glaucomatous Focal Perfusion Loss in the Macula Measured by Optical Coherence Tomographic Angiography. Am J Ophthalmol 2024; 268:181-189. [PMID: 39009239 DOI: 10.1016/j.ajo.2024.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Revised: 07/04/2024] [Accepted: 07/05/2024] [Indexed: 07/17/2024]
Abstract
PURPOSE To measure low perfusion area (LPA) and focal perfusion loss (FPL) in the macula using optical coherence tomography (OCT) angiography (OCTA) for glaucoma. DESIGN Prospective, cross-sectional "case-control" comparison study. METHODS A total of 60 patients with primary open-angle glaucoma (POAG) and 37 healthy participants were analyzed. AngioVue 6 × 6-mm high-definition (400 × 400 transverse pixels) macular OCTA scans were performed on one eye of each participant. Flow signal was calculated using the split-spectrum amplitude-decorrelation angiography algorithm. En face ganglion cell layer plexus (GCLP) and superficial vascular complex (SVC) images were generated. Using custom software, vessel density (VD) maps were obtained by computing the fraction of area occupied by flow pixels after low-pass filtering by local averaging 41 × 41 pixels. LPA was defined by local VD below 0.5 percentile over a contiguous area above 98.5 percentile of the healthy reference population. The FPL was the percentage VD loss (relative to normal mean) integrated over the LPA. RESULTS Among patients with POAG, 30 had perimetric and 30 had preperimetric glaucoma. The LPAGCLP-VD was 0.16±0.38 mm2 in normal and 5.78±6.30 mm2 in glaucoma subjects (P < .001). The FPLGCLP-VD was 0.20%±0.47% in normal and 7.52%±8.84% in glaucoma subjects (P < .001). The perimetric glaucoma diagnostic accuracy, measured by the area under the receiver operating curve, was 0.993 for LPAGCLP-VD and 0.990 for FPLGCLP-VD. The sensitivities were, respectively, 96.7% and 93.3% at 95% specificity. The LPAGCLP-VD and FPLGCLP-VD had good repeatability (0.957 and 0.952 by intraclass correlation coefficient). Diagnostic accuracy was better than GCLP VD (AROC 0.950, sensitivity 83.3%) and OCT ganglion cell complex (GCC) thickness (AROC 0.927, sensitivity 80.0%) and GCC focal loss volume (AROC 0.957, sensitivity 80.0%). The LPAGCLP-VD and FPLGCLP-VD correlated well with central VF mean deviations (Pearson r = -0.716 and -0.705 respectively, both P < .001). CONCLUSION Assessment of macular FPL using OCTA is useful in evaluating glaucomatous damage.
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Affiliation(s)
- Aiyin Chen
- From the Casey Eye Institute and Department of Ophthalmology, Oregon Health and Science University, Portland, Oregon, USA
| | - Ping Wei
- From the Casey Eye Institute and Department of Ophthalmology, Oregon Health and Science University, Portland, Oregon, USA
| | - Jie Wang
- From the Casey Eye Institute and Department of Ophthalmology, Oregon Health and Science University, Portland, Oregon, USA
| | - Liang Liu
- From the Casey Eye Institute and Department of Ophthalmology, Oregon Health and Science University, Portland, Oregon, USA
| | - Acner Camino
- From the Casey Eye Institute and Department of Ophthalmology, Oregon Health and Science University, Portland, Oregon, USA
| | - Yukun Guo
- From the Casey Eye Institute and Department of Ophthalmology, Oregon Health and Science University, Portland, Oregon, USA
| | - Ou Tan
- From the Casey Eye Institute and Department of Ophthalmology, Oregon Health and Science University, Portland, Oregon, USA
| | - Yali Jia
- From the Casey Eye Institute and Department of Ophthalmology, Oregon Health and Science University, Portland, Oregon, USA
| | - David Huang
- From the Casey Eye Institute and Department of Ophthalmology, Oregon Health and Science University, Portland, Oregon, USA..
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Heinke A, Zhang H, Deussen D, Galang CMB, Warter A, Kalaw FGP, Bartsch DUG, Cheng L, An C, Nguyen T, Freeman WR. ARTIFICIAL INTELLIGENCE FOR OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY-BASED DISEASE ACTIVITY PREDICTION IN AGE-RELATED MACULAR DEGENERATION. Retina 2024; 44:465-474. [PMID: 37988102 PMCID: PMC10922109 DOI: 10.1097/iae.0000000000003977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
PURPOSE The authors hypothesize that optical coherence tomography angiography (OCTA)-visualized vascular morphology may be a predictor of choroidal neovascularization status in age-related macular degeneration (AMD). The authors thus evaluated the use of artificial intelligence (AI) to predict different stages of AMD disease based on OCTA en face 2D projections scans. METHODS Retrospective cross-sectional study based on collected 2D OCTA data from 310 high-resolution scans. Based on OCT B-scan fluid and clinical status, OCTA was classified as normal, dry AMD, wet AMD active, and wet AMD in remission with no signs of activity. Two human experts graded the same test set, and a consensus grading between two experts was used for the prediction of four categories. RESULTS The AI can achieve 80.36% accuracy on a four-category grading task with 2D OCTA projections. The sensitivity of prediction by AI was 0.7857 (active), 0.7142 (remission), 0.9286 (dry AMD), and 0.9286 (normal) and the specificity was 0.9524, 0.9524, 0.9286, and 0.9524, respectively. The sensitivity of prediction by human experts was 0.4286 active choroidal neovascularization, 0.2143 remission, 0.8571 dry AMD, and 0.8571 normal with specificity of 0.7619, 0.9286, 0.7857, and 0.9762, respectively. The overall AI classification prediction was significantly better than the human (odds ratio = 1.95, P = 0.0021). CONCLUSION These data show that choroidal neovascularization morphology can be used to predict disease activity by AI; longitudinal studies are needed to better understand the evolution of choroidal neovascularization and features that predict reactivation. Future studies will be able to evaluate the additional predicative value of OCTA on top of other imaging characteristics (i.e., fluid location on OCT B scans) to help predict response to treatment.
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Affiliation(s)
- Anna Heinke
- Department of Ophthalmology at the Shiley Eye Institute, University of California at San Diego La Jolla, California
- Joan and Irwin Jacobs Retina Center, La Jolla, California
| | - Haochen Zhang
- Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, California; and
| | - Daniel Deussen
- Department of Ophthalmology at the Shiley Eye Institute, University of California at San Diego La Jolla, California
- Joan and Irwin Jacobs Retina Center, La Jolla, California
- University Eye Hospital, Ludwig-Maximillians-University, Munich, Germany
| | - Carlo Miguel B Galang
- Department of Ophthalmology at the Shiley Eye Institute, University of California at San Diego La Jolla, California
- Joan and Irwin Jacobs Retina Center, La Jolla, California
| | - Alexandra Warter
- Department of Ophthalmology at the Shiley Eye Institute, University of California at San Diego La Jolla, California
- Joan and Irwin Jacobs Retina Center, La Jolla, California
| | - Fritz Gerald P Kalaw
- Department of Ophthalmology at the Shiley Eye Institute, University of California at San Diego La Jolla, California
- Joan and Irwin Jacobs Retina Center, La Jolla, California
| | - Dirk-Uwe G Bartsch
- Department of Ophthalmology at the Shiley Eye Institute, University of California at San Diego La Jolla, California
- Joan and Irwin Jacobs Retina Center, La Jolla, California
| | - Lingyun Cheng
- Department of Ophthalmology at the Shiley Eye Institute, University of California at San Diego La Jolla, California
- Joan and Irwin Jacobs Retina Center, La Jolla, California
| | - Cheolhong An
- Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, California; and
| | - Truong Nguyen
- Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, California; and
| | - William R Freeman
- Department of Ophthalmology at the Shiley Eye Institute, University of California at San Diego La Jolla, California
- Joan and Irwin Jacobs Retina Center, La Jolla, California
- Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, California; and
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Waheed NK, Rosen RB, Jia Y, Munk MR, Huang D, Fawzi A, Chong V, Nguyen QD, Sepah Y, Pearce E. Optical coherence tomography angiography in diabetic retinopathy. Prog Retin Eye Res 2023; 97:101206. [PMID: 37499857 PMCID: PMC11268430 DOI: 10.1016/j.preteyeres.2023.101206] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 07/29/2023]
Abstract
There remain many unanswered questions on how to assess and treat the pathology and complications that arise from diabetic retinopathy (DR). Optical coherence tomography angiography (OCTA) is a novel and non-invasive three-dimensional imaging method that can visualize capillaries in all retinal layers. Numerous studies have confirmed that OCTA can identify early evidence of microvascular changes and provide quantitative assessment of the extent of diseases such as DR and its complications. A number of informative OCTA metrics could be used to assess DR in clinical trials, including measurements of the foveal avascular zone (FAZ; area, acircularity, 3D para-FAZ vessel density), vessel density, extrafoveal avascular zones, and neovascularization. Assessing patients with DR using a full-retinal slab OCTA image can limit segmentation errors and confounding factors such as those related to center-involved diabetic macular edema. Given emerging data suggesting the importance of the peripheral retinal vasculature in assessing and predicting DR progression, wide-field OCTA imaging should also be used. Finally, the use of automated methods and algorithms for OCTA image analysis, such as those that can distinguish between areas of true and false signals, reconstruct images, and produce quantitative metrics, such as FAZ area, will greatly improve the efficiency and standardization of results between studies. Most importantly, clinical trial protocols should account for the relatively high frequency of poor-quality data related to sub-optimal imaging conditions in DR and should incorporate time for assessing OCTA image quality and re-imaging patients where necessary.
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Affiliation(s)
- Nadia K Waheed
- New England Eye Center, Tufts University School of Medicine, Boston, MA, USA.
| | - Richard B Rosen
- New York Eye and Ear Infirmary of Mount Sinai, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Yali Jia
- School of Medicine, Casey Eye Institute, Oregon Health and Science University, Portland, OR, USA
| | - Marion R Munk
- Augenarzt-Praxisgemeinschaft Gutblick AG, Pfäffikon, Switzerland
| | - David Huang
- School of Medicine, Casey Eye Institute, Oregon Health and Science University, Portland, OR, USA
| | - Amani Fawzi
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Victor Chong
- Institute of Ophthalmology, University College London, London, UK
| | - Quan Dong Nguyen
- Byers Eye Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Yasir Sepah
- Byers Eye Institute, Stanford University School of Medicine, Stanford, CA, USA
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Ong CJT, Wong MYZ, Cheong KX, Zhao J, Teo KYC, Tan TE. Optical Coherence Tomography Angiography in Retinal Vascular Disorders. Diagnostics (Basel) 2023; 13:diagnostics13091620. [PMID: 37175011 PMCID: PMC10178415 DOI: 10.3390/diagnostics13091620] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 04/28/2023] [Accepted: 05/01/2023] [Indexed: 05/15/2023] Open
Abstract
Traditionally, abnormalities of the retinal vasculature and perfusion in retinal vascular disorders, such as diabetic retinopathy and retinal vascular occlusions, have been visualized with dye-based fluorescein angiography (FA). Optical coherence tomography angiography (OCTA) is a newer, alternative modality for imaging the retinal vasculature, which has some advantages over FA, such as its dye-free, non-invasive nature, and depth resolution. The depth resolution of OCTA allows for characterization of the retinal microvasculature in distinct anatomic layers, and commercial OCTA platforms also provide automated quantitative vascular and perfusion metrics. Quantitative and qualitative OCTA analysis in various retinal vascular disorders has facilitated the detection of pre-clinical vascular changes, greater understanding of known clinical signs, and the development of imaging biomarkers to prognosticate and guide treatment. With further technological improvements, such as a greater field of view and better image quality processing algorithms, it is likely that OCTA will play an integral role in the study and management of retinal vascular disorders. Artificial intelligence methods-in particular, deep learning-show promise in refining the insights to be gained from the use of OCTA in retinal vascular disorders. This review aims to summarize the current literature on this imaging modality in relation to common retinal vascular disorders.
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Affiliation(s)
- Charles Jit Teng Ong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore
| | - Mark Yu Zheng Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore
| | - Kai Xiong Cheong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore
| | - Jinzhi Zhao
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore
| | - Kelvin Yi Chong Teo
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program (EYE ACP), Duke-NUS Medical School, Singapore 169857, Singapore
| | - Tien-En Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program (EYE ACP), Duke-NUS Medical School, Singapore 169857, Singapore
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Optical Coherence Tomography Angiography (OCT-A) in Uveitis: A Literature Review and a Reassessment of Its Real Role. Diagnostics (Basel) 2023; 13:diagnostics13040601. [PMID: 36832089 PMCID: PMC9955936 DOI: 10.3390/diagnostics13040601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/21/2023] [Accepted: 02/02/2023] [Indexed: 02/10/2023] Open
Abstract
BACKGROUND The global and precise follow-up of uveitis has become possible with the availability of dual fluorescein (FA) and indocyanine green angiography (ICGA) since the mid-1990s. Progressively, additional non-invasive imaging methods have emerged, bringing value-added precision to the imaging appraisal of uveitis, including, among others, optical coherence tomography (OCT), enhanced-depth imaging OCT (EDI-OCT) and blue light fundus autofluorescence (BAF). More recently, another complementary imaging method, OCT-angiography (OCT-A), further allowed retinal and choroidal circulation to be imaged without the need for dye injection. PURPOSE The purpose of this review was aimed at examining the evidence in published reports indicating whether OCT-A could possibly replace dye angiographic methods, as well as the real practical impact of OCT-A. METHODS A literature search in the PubMed database was performed using the terms OCT-angiography and uveitis, OCTA and uveitis and OCT-A and uveitis. Case reports were excluded. Articles were classified into technical reports, research reports and reviews. Articles in the two latter categories were analyzed in a more detailed, individual fashion. Special attention was paid to whether there were arguments in favor of an exclusive rather than complementary use of OCT-A. Furthermore, a synthesis of the main practical applications of OCT-A in the management of uveitis was attempted. RESULTS Between 2016 (the year of the first articles) and 2022, 144 articles containing the search terms were identified. After excluding case report articles, 114 articles were retained: 4 in 2016, 17 in 2017, 14 in 2018, 21 in 2019, 14 in 2020, 18 in 2021 and 26 in 2022. Seven articles contained technical information or consensus-based terminology. Ninety-two articles could be considered as clinical research articles. Of those, only two hinted in their conclusions that OCT-A could hypothetically replace dye methods. The terms mostly used to qualify the contribution of the articles in this group were "complementary to dye methods", "adjunct", "supplementing" and other similar terms. Fifteen articles were reviews, none of which hinted that OCT-A could replace dye methods. The situations where OCT-A represented a significant practical contribution to the practical appraisal of uveitis were identified. CONCLUSION To date, no evidence was found in the literature that OCT-A can replace the classic dye methods; however, it can complement them. Promoting the possibility that non-invasive OCT-A can substitute the invasive dye methods is deleterious, giving the elusive impression that dye methods are no longer inevitable for evaluating uveitis patients. Nevertheless, OCT-A is a precious tool in uveitis research.
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Cheng W, Song Y, Gao X, Lin F, Li F, Wang P, Hu K, Li H, Li Y, Chen L, Jonas JB, Wang W, Zhang X. Axial Length and Choriocapillaris Flow Deficits in Non-pathological High Myopia. Am J Ophthalmol 2022; 244:68-78. [PMID: 35970207 DOI: 10.1016/j.ajo.2022.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 08/04/2022] [Accepted: 08/04/2022] [Indexed: 01/30/2023]
Abstract
PURPOSE To examine the relationship between axial length (AL) and choriocapillaris (CC) flow deficits percentage (FD%) in non-pathological highly myopic eyes. DESIGN Prospective cross-sectional study. METHODS This study included Chinese patients with non-pathological high myopia, which was defined by an AL of > 26 mm and a META-PM classification grade of <2. Swept-source optical coherence tomography angiography was used to obtain 6 × 6 mm images of the macular CC. The CC FD% was measured in the fovea, parafovea, and perifovea subfields. RESULTS A total of 1017 individuals (1017 eyes) with a mean age of 35.95 ± 14.11 years were included. After adjusting for age, sex, intraocular pressure, body mass index, systolic blood pressure, and image quality score, the overall CC FD% increased by 0.27% (95% CI 0.02, 0.52; P = .034) for each mm increase in AL. Among subfields, longer AL was associated with a higher CC FD% in the perifovea (β = 0.53, 95% CI 0.30, 0.77; P < .001), and was not associated with a higher CC FD% in the parafovea (β = 0.08, 95% CI -0.26, 0.42; P = .652) and fovea (β = 0.001, 95% CI -0.50, 0.50; P = .999). CONCLUSIONS The CC FD% increased with a longer AL in high myopia in the perifovea region but not in the fovea and parafovea fields. These findings may be of interest in elucidating the etiology of myopic axial elongation.
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Affiliation(s)
- Weijing Cheng
- From State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China (W.C, Y.S, X.G, F.L, F.L, P.W, K.H, W.W, X.Z)
| | - Yunhe Song
- From State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China (W.C, Y.S, X.G, F.L, F.L, P.W, K.H, W.W, X.Z)
| | - Xinbo Gao
- From State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China (W.C, Y.S, X.G, F.L, F.L, P.W, K.H, W.W, X.Z)
| | - Fengbin Lin
- From State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China (W.C, Y.S, X.G, F.L, F.L, P.W, K.H, W.W, X.Z)
| | - Fei Li
- From State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China (W.C, Y.S, X.G, F.L, F.L, P.W, K.H, W.W, X.Z)
| | - Peiyuan Wang
- From State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China (W.C, Y.S, X.G, F.L, F.L, P.W, K.H, W.W, X.Z)
| | - Kun Hu
- From State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China (W.C, Y.S, X.G, F.L, F.L, P.W, K.H, W.W, X.Z)
| | - Hao Li
- Ophthalmology Department, Guizhou Provincial People's Hospital, Guiyang, China (H.L)
| | - Yingjie Li
- Department of Ophthalmology, The First Hospital of Nanchang City, Nanchang, China (Y.L)
| | - Lina Chen
- Department of Ophthalmology, The People's Third Hospital of Dalian, Dalian Medical University, Dalian, China (L.C)
| | - Jost B Jonas
- Department of Ophthalmology, Medical Faculty Mannheim, Heidelberg University, Germany (J.B.J); Institute of Molecular and Clinical Ophthalmology Basel, Switzerland (J.B.J)
| | - Wei Wang
- From State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China (W.C, Y.S, X.G, F.L, F.L, P.W, K.H, W.W, X.Z).
| | - Xiulan Zhang
- From State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China (W.C, Y.S, X.G, F.L, F.L, P.W, K.H, W.W, X.Z).
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9
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Nam AS, Braaf B, Vakoc BJ. Using the dynamic forward scattering signal for optical coherence tomography based blood flow quantification. OPTICS LETTERS 2022; 47:3083-3086. [PMID: 35709056 PMCID: PMC9580005 DOI: 10.1364/ol.455475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
To our knowledge, all existing optical coherence tomography approaches for quantifying blood flow, whether Doppler-based or decorrelation-based, analyze light that is back-scattered by moving red blood cells (RBCs). This work investigates the potential advantages of basing these measurements on light that is forward-scattered by RBCs, i.e., by looking at the signals back-scattered from below the vessel. We show experimentally that flowmetry based on forward-scattering is insensitive to vessel orientation for vessels that are approximately orthogonal to the imaging beam. We further provide proof-of-principle demonstrations of dynamic forward-scattering (DFS) flowmetry in human retinal and choroidal vessels.
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Affiliation(s)
- Ahhyun Stephanie Nam
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom St, Boston, MA 02114 USA
- Harvard Medical School, 25 Shattuck St, Boston, MA 02115 USA
| | - Boy Braaf
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom St, Boston, MA 02114 USA
- Harvard Medical School, 25 Shattuck St, Boston, MA 02115 USA
| | - Benjamin J. Vakoc
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom St, Boston, MA 02114 USA
- Harvard Medical School, 25 Shattuck St, Boston, MA 02115 USA
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10
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Directional analysis of intensity changes for determining the existence of cyst in optical coherence tomography images. Sci Rep 2022; 12:2105. [PMID: 35136133 PMCID: PMC8825816 DOI: 10.1038/s41598-022-06099-6] [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: 05/01/2021] [Accepted: 01/24/2022] [Indexed: 11/23/2022] Open
Abstract
Diabetic retinopathy (DR) is an important cause of blindness in people with the long history of diabetes. DR is caused due to the damage to blood vessels in the retina. One of the most important manifestations of DR is the formation of fluid-filled regions between retinal layers. The evaluation of stage and transcribed drugs can be possible through the analysis of retinal Optical Coherence Tomography (OCT) images. Therefore, the detection of cysts in OCT images and the is of considerable importance. In this paper, a fast method is proposed to determine the status of OCT images as cystic or non-cystic. The method consists of three phases which are pre-processing, boundary pixel determination and post-processing. After applying a noise reduction method in the pre-processing step, the method finds the pixels which are the boundary pixels of cysts. This process is performed by finding the significant intensity changes in the vertical direction and considering rectangular patches around the candidate pixels. The patches are verified whether or not they contain enough pixels making considerable diagonal intensity changes. Then, a shadow omission method is proposed in the post-processing phase to extract the shadow regions which can be mistakenly considered as cystic areas. Then, the pixels extracted in the previous phase that are near the shadow regions are removed to prevent the production of false positive cases. The performance of the proposed method is evaluated in terms of sensitivity and specificity on real datasets. The experimental results show that the proposed method produces outstanding results from both accuracy and speed points of view.
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11
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You QS, Camino A, Wang J, Guo Y, Flaxel CJ, Hwang TS, Huang D, Jia Y, Bailey ST. Geographic Atrophy Progression Is Associated With Choriocapillaris Flow Deficits Measured With Optical Coherence Tomographic Angiography. Invest Ophthalmol Vis Sci 2021; 62:28. [PMID: 34964802 PMCID: PMC8727307 DOI: 10.1167/iovs.62.15.28] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose The purpose of this study was to assess the associations between baseline choriocapillaris (CC) flow deficits and geographic atrophy (GA) progression. Methods In this prospective cohort study, patients with GA underwent 3 × 3-mm macular spectral-domain optical coherence tomographic angiography (OCTA) at baseline and follow-up visits. Annual GA enlargement rate was defined as change of square root of GA area in 12 months. Shadow areas due to iris, media opacity, retinal vessels, and drusen were excluded. CC vessel density (CC-VD) in non-GA areas was measured using a validated machine-learning-based algorithm. Low perfusion area (LPA) was defined as capillary density below the 0.1 percentile threshold of the same location of 40 normal healthy control eye. Focal perfusion loss (FPL) was defined as percentage of CC loss within LPA compared with normal controls. Results Ten patients with GA were enrolled and followed for 26 months on average. At baseline, the mean GA area was 0.84 ± 0.70 mm2. The mean CC-VD was 44.5 ± 15.2%, the mean LPA was 4.29 ± 2.6 mm2, and the mean FPL was 50.4 ± 28.2%. The annual GA enlargement rate was significantly associated with baseline CC-VD (r = -0.816, P = 0.004), LPA (r = 0.809, P = 0.005), and FPL (r = 0.800, P = 0.005), but not with age (r = 0.008, P = 0.98) and GA area (r = -0.362, P = 0.30). Conclusions Baseline CC flow deficits were significantly associated with a faster GA enlargement over the course of 1 year, suggesting the choriocapillaris perfusion outside of a GA area may play a role in GA progression.
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Affiliation(s)
- Qi Sheng You
- Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, United States.,Kresge Eye Institute, Detroit Medical Center, Wayne State University, Detroit, Michigan, United States
| | - Acner Camino
- Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, United States
| | - Jie Wang
- Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, United States.,Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, United States
| | - Yukun Guo
- Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, United States
| | - Christina J Flaxel
- Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, United States
| | - Thomas S Hwang
- Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, United States
| | - David Huang
- Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, United States
| | - Yali Jia
- Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, United States.,Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, United States
| | - Steven T Bailey
- Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, United States
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12
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Hormel TT, Hwang TS, Bailey ST, Wilson DJ, Huang D, Jia Y. Artificial intelligence in OCT angiography. Prog Retin Eye Res 2021; 85:100965. [PMID: 33766775 PMCID: PMC8455727 DOI: 10.1016/j.preteyeres.2021.100965] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 03/09/2021] [Accepted: 03/15/2021] [Indexed: 12/21/2022]
Abstract
Optical coherence tomographic angiography (OCTA) is a non-invasive imaging modality that provides three-dimensional, information-rich vascular images. With numerous studies demonstrating unique capabilities in biomarker quantification, diagnosis, and monitoring, OCTA technology has seen rapid adoption in research and clinical settings. The value of OCTA imaging is significantly enhanced by image analysis tools that provide rapid and accurate quantification of vascular features and pathology. Today, the most powerful image analysis methods are based on artificial intelligence (AI). While AI encompasses a large variety of techniques, machine-learning-based, and especially deep-learning-based, image analysis provides accurate measurements in a variety of contexts, including different diseases and regions of the eye. Here, we discuss the principles of both OCTA and AI that make their combination capable of answering new questions. We also review contemporary applications of AI in OCTA, which include accurate detection of pathologies such as choroidal neovascularization, precise quantification of retinal perfusion, and reliable disease diagnosis.
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Affiliation(s)
- Tristan T Hormel
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Thomas S Hwang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Steven T Bailey
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - David J Wilson
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - David Huang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Yali Jia
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA; Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR, 97239, USA.
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13
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Wang TF, Chen DS, Zhu JW, Zhu B, Wang ZL, Cao JG, Feng CH, Zhao JW. Unsupervised Machine Learning-Based Analysis of Clinical Features, Bone Mineral Density Features and Medical Care Costs of Rotator Cuff Tears. Risk Manag Healthc Policy 2021; 14:3977-3986. [PMID: 34588829 PMCID: PMC8472212 DOI: 10.2147/rmhp.s330555] [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: 07/21/2021] [Accepted: 09/16/2021] [Indexed: 11/30/2022] Open
Abstract
Purpose We aim to present unsupervised machine learning-based analysis of clinical features, bone mineral density (BMD) features, and medical care costs of Rotator cuff tears (RCT). Patients and Methods Fifty-three patients with RCT were reviewed, the clinical features, BMD features, and medical care costs were collected and analyzed by descriptive statistics. Furtherly, unsupervised machine learning (UML) algorithm was used for dimensionality reduction and cluster analysis of the RCT data. Results There were 26 males and 27 females. The patients were divided into four subgroups using the UML algorithm. There were significant differences among four subgroups regarding trauma exposure, full-thickness supraspinatus tendon tears, infraspinatus tendon tear, subscapularis tendon tear, BMD distribution, medial row anchors, lateral row anchors, total medical care costs, and consumables costs. We observed the highest frequency of trauma exposure, infraspinatus tendon tear, subscapularis tendon tear, osteoporosis, the highest number of medial row anchors, lateral row anchors, total medical care costs, and consumables costs in subgroup II. Conclusion The unsupervised machine learning-based analysis of RCT can provide clinically meaningful classification, which shows good interpretability and contribute to a better understanding of RCT. The significance of the results is limited due to the small number of samples, a larger follow-up study is needed to confirm the encouraging results.
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Affiliation(s)
- Tong-Fu Wang
- Department of Sports Medicine and Arthroscopy, Tianjin Hospital of Tianjin University, Tianjin, People's Republic of China
| | - De-Sheng Chen
- Department of Sports Medicine and Arthroscopy, Tianjin Hospital of Tianjin University, Tianjin, People's Republic of China
| | - Jia-Wang Zhu
- Department of Sports Medicine and Arthroscopy, Tianjin Hospital of Tianjin University, Tianjin, People's Republic of China
| | - Bo Zhu
- Department of Sports Medicine and Arthroscopy, Tianjin Hospital of Tianjin University, Tianjin, People's Republic of China
| | - Zeng-Liang Wang
- Department of Sports Medicine and Arthroscopy, Tianjin Hospital of Tianjin University, Tianjin, People's Republic of China
| | - Jian-Gang Cao
- Department of Sports Medicine and Arthroscopy, Tianjin Hospital of Tianjin University, Tianjin, People's Republic of China
| | - Cai-Hong Feng
- Department of Sports Medicine and Arthroscopy, Tianjin Hospital of Tianjin University, Tianjin, People's Republic of China
| | - Jun-Wei Zhao
- Department of Sports Medicine and Arthroscopy, Tianjin Hospital of Tianjin University, Tianjin, People's Republic of China
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14
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Yeung L, Lee YC, Lin YT, Lee TW, Lai CC. Macular Ischemia Quantification Using Deep-Learning Denoised Optical Coherence Tomography Angiography in Branch Retinal Vein Occlusion. Transl Vis Sci Technol 2021; 10:23. [PMID: 34137837 PMCID: PMC8212432 DOI: 10.1167/tvst.10.7.23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Purpose To examine whether deep-learning denoised optical coherence tomography angiography (OCTA) images could enhance automated macular ischemia quantification in branch retinal vein occlusion (BRVO). Methods This retrospective, single-center, cross-sectional study enrolled 74 patients with BRVO and 46 age-matched healthy subjects. The severity of macular ischemia was graded as mild, moderate, or severe. Denoised OCTA images were produced using a neural network model. Quantitative parameters derived from denoised images, including vessel density and nonperfusion area, were compared with those derived from the OCTA machine. The main outcome measures were correlations between quantitative parameters, and areas under receiver operating characteristic curves (AUCs) in classifying the severity of the macular ischemia. Results The vessel density and nonperfusion area from denoised images were correlated strongly with the corresponding parameters from machine-derived images in control eyes and BRVO eyes with mild or moderate macular ischemia (all P < 0.001). However, no such correlation was found in eyes with severe macular ischemia. The vessel density and nonperfusion area from denoised images had significantly larger area under receiver operating characteristic curve than those derived from the original images in classifying moderate versus severe macular ischemia (0.927 vs 0.802 [P = 0.042] and 0.946 vs 0.797, [P = 0.022], respectively). There were no significant differences in the areas under receiver operating characteristic curve between the denoised images and the machine-derived parameters in classifying control versus BRVO, and mild versus moderate macular ischemia. Conclusions A neural network model is useful for removing speckle noise on OCTA images and facilitating the automated grading of macular ischemia in eyes with BRVO. Translational Relevance Deep-learning denoised optical coherence tomography angiography images could enhance automated macular ischemia quantification.
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Affiliation(s)
- Ling Yeung
- Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yih-Cherng Lee
- Graduate Institute of Communication Engineering, National Taiwan University, Taiwan
| | - Yu-Tze Lin
- Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Tay-Wey Lee
- Biostatistical Consultation Center, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Chi-Chun Lai
- Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
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15
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Quantification of Nonperfusion Area in Montaged Widefield OCT Angiography Using Deep Learning in Diabetic Retinopathy. OPHTHALMOLOGY SCIENCE 2021; 1:100027. [PMID: 36249293 PMCID: PMC9560579 DOI: 10.1016/j.xops.2021.100027] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 04/29/2021] [Accepted: 05/04/2021] [Indexed: 01/01/2023]
Abstract
Purpose To examine the efficacy of a deep learning-based algorithm to quantify the nonperfusion area (NPA) on montaged widefield OCT angiography (OCTA) for assessment of diabetic retinopathy (DR) severity. Design Cross-sectional study. Participants One hundred thirty-seven participants with a full range of DR severity and 26 healthy participants. Methods A deep learning-based algorithm was developed for detecting and quantifying NPA in the superficial vascular complex on widefield OCTA comprising 3 horizontally montaged 6 × 6-mm OCTA scans from the nasal, macular, and temporal regions. We trained the algorithm on 978 volumetric OCTA scans from all participants using 5-fold cross-validation. The algorithm can distinguish NPA from shadow artifacts. The F1 score evaluated segmentation accuracy. The area under the receiver operating characteristic curve and sensitivity with specificity fixed at 95% quantified network performance to distinguish patients with diabetes from healthy control participants, referable DR from nonreferable DR (nonproliferative DR [NPDR] less than moderate severity), and severe DR (severe NPDR, proliferative DR, or DR with edema) from nonsevere DR (mild to moderate NPDR). Main Outcome Measures Widefield OCTA NPA, visual acuity (VA), and DR severities. Results Automatically segmented NPA showed high agreement with the manually delineated ground truth, with a mean ± standard deviation F1 score of 0.78 ± 0.05 in nasal, 0.82 ± 0.07 in macular, and 0.78 ± 0.05 in temporal scans. The extrafoveal avascular area (EAA) in the macular scan showed the best sensitivity at 54% for differentiating those with diabetes from healthy control participants, whereas montaged widefield OCTA scan showed significantly higher sensitivity than macular scans (P < 0.0001, McNemar’s test) for detecting eyes with DR at 66%, referable DR at 63%, and severe DR at 62%. Montaged widefield OCTA showed the highest correlation (Spearman ρ = 0.74; P < 0.0001) between EAA and DR severity. The macular scan showed the strongest negative correlation (Pearson ρ = –0.42; P < 0.0001) between EAA and best-corrected VA. Conclusions A deep learning-based algorithm for montaged widefield OCTA can detect NPA accurately and can improve the detection of clinically important DR.
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16
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Ringel MJ, Tang EM, Tao YK. Advances in multimodal imaging in ophthalmology. Ther Adv Ophthalmol 2021; 13:25158414211002400. [PMID: 35187398 PMCID: PMC8855415 DOI: 10.1177/25158414211002400] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 02/23/2021] [Indexed: 12/12/2022] Open
Abstract
Multimodality ophthalmic imaging systems aim to enhance the contrast, resolution, and functionality of existing technologies to improve disease diagnostics and therapeutic guidance. These systems include advanced acquisition and post-processing methods using optical coherence tomography (OCT), combined scanning laser ophthalmoscopy and OCT systems, adaptive optics, surgical guidance, and photoacoustic technologies. Here, we provide an overview of these ophthalmic imaging systems and their clinical and basic science applications.
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Affiliation(s)
- Morgan J. Ringel
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Eric M. Tang
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Yuankai K. Tao
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37235, USA
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17
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Ma Y, Hao H, Xie J, Fu H, Zhang J, Yang J, Wang Z, Liu J, Zheng Y, Zhao Y. ROSE: A Retinal OCT-Angiography Vessel Segmentation Dataset and New Model. IEEE TRANSACTIONS ON MEDICAL IMAGING 2021; 40:928-939. [PMID: 33284751 DOI: 10.1109/tmi.2020.3042802] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Optical Coherence Tomography Angiography (OCTA) is a non-invasive imaging technique that has been increasingly used to image the retinal vasculature at capillary level resolution. However, automated segmentation of retinal vessels in OCTA has been under-studied due to various challenges such as low capillary visibility and high vessel complexity, despite its significance in understanding many vision-related diseases. In addition, there is no publicly available OCTA dataset with manually graded vessels for training and validation of segmentation algorithms. To address these issues, for the first time in the field of retinal image analysis we construct a dedicated Retinal OCTA SEgmentation dataset (ROSE), which consists of 229 OCTA images with vessel annotations at either centerline-level or pixel level. This dataset with the source code has been released for public access to assist researchers in the community in undertaking research in related topics. Secondly, we introduce a novel split-based coarse-to-fine vessel segmentation network for OCTA images (OCTA-Net), with the ability to detect thick and thin vessels separately. In the OCTA-Net, a split-based coarse segmentation module is first utilized to produce a preliminary confidence map of vessels, and a split-based refined segmentation module is then used to optimize the shape/contour of the retinal microvasculature. We perform a thorough evaluation of the state-of-the-art vessel segmentation models and our OCTA-Net on the constructed ROSE dataset. The experimental results demonstrate that our OCTA-Net yields better vessel segmentation performance in OCTA than both traditional and other deep learning methods. In addition, we provide a fractal dimension analysis on the segmented microvasculature, and the statistical analysis demonstrates significant differences between the healthy control and Alzheimer's Disease group. This consolidates that the analysis of retinal microvasculature may offer a new scheme to study various neurodegenerative diseases.
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18
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Elbeyli A, Kurtul B. The influence of topical cyclopentolate instillation on peripapillary and macular microvasculature measured by optical coherence tomography angiography in healthy individuals. J Curr Ophthalmol 2021; 33:437-443. [PMID: 35128191 PMCID: PMC8772493 DOI: 10.4103/joco.joco_84_21] [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: 03/15/2021] [Revised: 06/11/2021] [Accepted: 06/11/2021] [Indexed: 11/13/2022] Open
Abstract
Purpose: To investigate the influence of topical cyclopentolate 1%, as an anti-muscarinic mydriatic agent, on the peripapillary and macular microvasculature by optical coherence tomography angiography (OCT-A) in healthy adults. Methods: A total of 41 healthy adults without any systemic or ocular disease were enrolled for this prospective consecutive study. All patients underwent OCT-A measurements (OptoVue Inc., Freemont, CA, USA) to assess optic disc status for radial peripapillary capillary network (whole image, inside disc, and peripapillary capillary densities), and superficial and deep capillary plexus whole, foveal, parafoveal and perifoveal densities, and foveal avascular zone (FAZ) densities. Foveal retinal thicknesses and all quadrant retinal fiber layer thicknesses were also assessed. The 4.5 mm × 4.5 mm peripapillary and 6 mm × 6 mm macular OCT-A images were undertaken before and 30 min after instillation of topical cyclopentolate 1% to the right eyes. Results: The mean age of subjects was 38.14 ± 14.10 years. All macular, optic disc, and FAZ densities, foveal retinal thicknesses, average, and all quadrant retinal fiber layer thicknesses were statistically similar between baseline and after administration of topical cyclopentolate 1% (P > 0.05). Conclusion: The current study demonstrated that pupillary dilation with topical cyclopentolate 1% seems to have no statistical effect on macular and peripapillary OCT-A measurements of healthy adults.
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19
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Hormel TT, Jia Y, Jian Y, Hwang TS, Bailey ST, Pennesi ME, Wilson DJ, Morrison JC, Huang D. Plexus-specific retinal vascular anatomy and pathologies as seen by projection-resolved optical coherence tomographic angiography. Prog Retin Eye Res 2021; 80:100878. [PMID: 32712135 PMCID: PMC7855241 DOI: 10.1016/j.preteyeres.2020.100878] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 05/13/2020] [Accepted: 05/18/2020] [Indexed: 12/22/2022]
Abstract
Optical coherence tomographic angiography (OCTA) is a novel technology capable of imaging retinal vasculature three-dimensionally at capillary scale without the need to inject any extrinsic dye contrast. However, projection artifacts cause superficial retinal vascular patterns to be duplicated in deeper layers, thus interfering with the clean visualization of some retinal plexuses and vascular pathologies. Projection-resolved OCTA (PR-OCTA) uses post-processing algorithms to reduce projection artifacts. With PR-OCTA, it is now possible to resolve up to 4 distinct retinal vascular plexuses in the living human eye. The technology also allows us to detect and distinguish between various retinal and optic nerve diseases. For example, optic nerve diseases such as glaucoma primarily reduces the capillary density in the superficial vascular complex, which comprises the nerve fiber layer plexus and the ganglion cell layer plexus. Outer retinal diseases such as retinitis pigmentosa primarily reduce the capillary density in the deep vascular complex, which comprises the intermediate capillary plexus and the deep capillary plexus. Retinal vascular diseases such as diabetic retinopathy and vein occlusion affect all plexuses, but with different patterns of capillary loss and vascular malformations. PR-OCTA is also useful in distinguishing various types of choroidal neovascularization and monitoring their response to anti-angiogenic medications. In retinal angiomatous proliferation and macular telangiectasia type 2, PR-OCTA can trace the pathologic vascular extension into deeper layers as the disease progress through stages. Plexus-specific visualization and measurement of retinal vascular changes are improving our ability to diagnose, stage, monitor, and assess treatment response in a wide variety of optic nerve and retinal diseases. These applications will be further enhanced with the continuing improvement of the speed and resolution of the OCT platforms, as well as the development of software algorithms to reduce artifacts, improve image quality, and make quantitative measurements.
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Affiliation(s)
- Tristan T Hormel
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Yali Jia
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA; Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Yifan Jian
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA; Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Thomas S Hwang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Steven T Bailey
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Mark E Pennesi
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - David J Wilson
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - John C Morrison
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - David Huang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, 97239, USA.
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20
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Borkovkina S, Camino A, Janpongsri W, Sarunic MV, Jian Y. Real-time retinal layer segmentation of OCT volumes with GPU accelerated inferencing using a compressed, low-latency neural network. BIOMEDICAL OPTICS EXPRESS 2020; 11:3968-3984. [PMID: 33014579 PMCID: PMC7510892 DOI: 10.1364/boe.395279] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/18/2020] [Accepted: 06/18/2020] [Indexed: 05/18/2023]
Abstract
Segmentation of retinal layers in optical coherence tomography (OCT) is an essential step in OCT image analysis for screening, diagnosis, and assessment of retinal disease progression. Real-time segmentation together with high-speed OCT volume acquisition allows rendering of en face OCT of arbitrary retinal layers, which can be used to increase the yield rate of high-quality scans, provide real-time feedback during image-guided surgeries, and compensate aberrations in adaptive optics (AO) OCT without using wavefront sensors. We demonstrate here unprecedented real-time OCT segmentation of eight retinal layer boundaries achieved by 3 levels of optimization: 1) a modified, low complexity, neural network structure, 2) an innovative scheme of neural network compression with TensorRT, and 3) specialized GPU hardware to accelerate computation. Inferencing with the compressed network U-NetRT took 3.5 ms, improving by 21 times the speed of conventional U-Net inference without reducing the accuracy. The latency of the entire pipeline from data acquisition to inferencing was only 41 ms, enabled by parallelized batch processing. The system and method allow real-time updating of en face OCT and OCTA visualizations of arbitrary retinal layers and plexuses in continuous mode scanning. To the best our knowledge, our work is the first demonstration of an ophthalmic imager with embedded artificial intelligence (AI) providing real-time feedback.
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Affiliation(s)
| | - Acner Camino
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 27239, USA
| | - Worawee Janpongsri
- Department of Engineering Science, Simon Fraser University, Burnaby, Canada
| | - Marinko V. Sarunic
- Department of Engineering Science, Simon Fraser University, Burnaby, Canada
| | - Yifan Jian
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 27239, USA
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR 97239, USA
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21
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The effect of topical tropicamide and phenylephrine on macular and peripapillary microvasculature: an optical coherence tomography angiography study. Int Ophthalmol 2020; 40:1969-1976. [DOI: 10.1007/s10792-020-01371-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 04/10/2020] [Indexed: 12/23/2022]
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22
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Díaz M, Díez-Sotelo M, Gómez-Ulla F, Novo J, Penedo MFG, Ortega M. Automatic Visual Acuity Estimation by Means of Computational Vascularity Biomarkers Using Oct Angiographies. SENSORS (BASEL, SWITZERLAND) 2019; 19:s19214732. [PMID: 31683559 PMCID: PMC6864478 DOI: 10.3390/s19214732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 10/22/2019] [Accepted: 10/29/2019] [Indexed: 06/10/2023]
Abstract
Optical Coherence Tomography Angiography (OCTA) constitutes a new non-invasive ophthalmic image modality that allows the precise visualization of the micro-retinal vascularity that is commonly used to analyze the foveal region. Given that there are many systemic and eye diseases that affect the eye fundus and its vascularity, the analysis of that region is crucial to diagnose and estimate the vision loss. The Visual Acuity (VA) is typically measured manually, implying an exhaustive and time-consuming procedure. In this work, we propose a method that exploits the information of the OCTA images to automatically estimate the VA with an accurate error of 0.1713.
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Affiliation(s)
- Macarena Díaz
- Grupo VARPA, Instituto de Investigación Biomédica de A Coruña (INIBIC), Universidade da Coruña, 15006 A Coruña, Spain.
- Centro de Investigación CITIC, Universidade da Coruña, 15071 A Coruña, Spain.
| | - Marta Díez-Sotelo
- Complejo Hospitalario Universitario de Santiago, 15706 Santiago de Compostela, Spain.
| | - Francisco Gómez-Ulla
- Complejo Hospitalario Universitario de Santiago, 15706 Santiago de Compostela, Spain.
- Instituto Oftalmológico Gómez-Ulla, 15706 Santiago de Compostela, Spain.
| | - Jorge Novo
- Grupo VARPA, Instituto de Investigación Biomédica de A Coruña (INIBIC), Universidade da Coruña, 15006 A Coruña, Spain.
- Centro de Investigación CITIC, Universidade da Coruña, 15071 A Coruña, Spain.
| | - Manuel Francisco G Penedo
- Grupo VARPA, Instituto de Investigación Biomédica de A Coruña (INIBIC), Universidade da Coruña, 15006 A Coruña, Spain.
- Centro de Investigación CITIC, Universidade da Coruña, 15071 A Coruña, Spain.
| | - Marcos Ortega
- Grupo VARPA, Instituto de Investigación Biomédica de A Coruña (INIBIC), Universidade da Coruña, 15006 A Coruña, Spain.
- Centro de Investigación CITIC, Universidade da Coruña, 15071 A Coruña, Spain.
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23
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Camino A, Guo Y, You Q, Wang J, Huang D, Bailey ST, Jia Y. Detecting and measuring areas of choriocapillaris low perfusion in intermediate, non-neovascular age-related macular degeneration. NEUROPHOTONICS 2019; 6:041108. [PMID: 31528658 PMCID: PMC6739623 DOI: 10.1117/1.nph.6.4.041108] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Accepted: 08/16/2019] [Indexed: 05/06/2023]
Abstract
Age-related macular degeneration (AMD) is a vision-threatening disease that affects the outer retina and choroid of elderly adults. Because photoreceptors are found in the outer retina and rely primarily on the trophic support of the underlying choriocapillaris, imaging of flow or lack thereof in choriocapillaris by optical coherence tomography angiography (OCTA) has great clinical potential in AMD assessment. We introduce a metric using OCTA, named "focal perfusion loss" (FPL) to describe the effects of age and non-neovascular AMD on choriocapillaris flow. Because OCTA imaging of choriocapillaris is vulnerable to artifacts-namely motion, projections, segmentation errors, and shadows-they are removed by postprocessing software. The shadow detection software is a machine learning algorithm recently developed for the evaluation of the retinal circulation and here adapted for choriocapillaris analysis. It aims to exclude areas with unreliable flow signal due to blocking of the OCT beam by objects anterior to the choriocapillaris (e.g., drusen, retinal vessels, vitreous floaters, and iris). We found that both the FPL and the capillary density were able to detect changes in the choriocapillaris of AMD and healthy age-matched subjects with respect to young controls. The dominant cause of shadowing in AMD is drusen, and the shadow exclusion algorithm helps determine which areas under drusen retain sufficient signal for perfusion evaluation and which areas must be excluded. Such analysis allowed us to determine unambiguously that choriocapillaris density under drusen is indeed reduced.
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Affiliation(s)
- Acner Camino
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Yukun Guo
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Qisheng You
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Jie Wang
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - David Huang
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Steven T. Bailey
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
| | - Yali Jia
- Oregon Health and Science University, Casey Eye Institute, Portland, Oregon, United States
- Address all correspondence to Yali Jia, E-mail:
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24
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Guo Y, Hormel TT, Xiong H, Wang B, Camino A, Wang J, Huang D, Hwang TS, Jia Y. Development and validation of a deep learning algorithm for distinguishing the nonperfusion area from signal reduction artifacts on OCT angiography. BIOMEDICAL OPTICS EXPRESS 2019; 10:3257-3268. [PMID: 31360599 PMCID: PMC6640834 DOI: 10.1364/boe.10.003257] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/24/2019] [Accepted: 05/28/2019] [Indexed: 05/06/2023]
Abstract
The capillary nonperfusion area (NPA) is a key quantifiable biomarker in the evaluation of diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA). However, signal reduction artifacts caused by vitreous floaters, pupil vignetting, or defocus present significant obstacles to accurate quantification. We have developed a convolutional neural network, MEDnet-V2, to distinguish NPA from signal reduction artifacts in 6×6 mm2 OCTA. The network achieves strong specificity and sensitivity for NPA detection across a wide range of DR severity and scan quality.
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Affiliation(s)
- Yukun Guo
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
- These authors contributed equally
| | - Tristan T. Hormel
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
- These authors contributed equally
| | - Honglian Xiong
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
- School of Physics and Optoelectronic Engineering, Foshan University, Foshan, Guangdong 528000, China
| | - Bingjie Wang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Acner Camino
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Jie Wang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR 97239, USA
| | - David Huang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Thomas S. Hwang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Yali Jia
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR 97239, USA
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25
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Podoleanu A, Izatt J, Lumbroso B, Pircher M, Rosen R, Weitz R. Progress in Multimodal En Face Imaging: feature introduction. BIOMEDICAL OPTICS EXPRESS 2019; 10:2135-2140. [PMID: 31086718 PMCID: PMC6484991 DOI: 10.1364/boe.10.002135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Indexed: 06/09/2023]
Abstract
This feature issue contains papers that report on the most recent advances in the field of en face optical coherence tomography (OCT) and of combinations of modalities facilitated by the en face view. Hardware configurations for delivery of en face OCT images are described as well as specific signal and image processing techniques tailored to deliver relevant clinical diagnoses. The value of the en face perspective for enabling multimodality is illustrated by several combination modalities.
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