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Wen Y, Chen Z, McAlinden C, Zhou X, Huang J. Recent advances in corneal neovascularization imaging. Exp Eye Res 2024; 244:109930. [PMID: 38750782 DOI: 10.1016/j.exer.2024.109930] [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: 11/08/2023] [Revised: 04/25/2024] [Accepted: 05/12/2024] [Indexed: 05/19/2024]
Abstract
Corneal neovascularization (CoNV) is a vision-threatening ocular disease commonly secondary to infectious, inflammatory, and traumatic etiologies. Slit lamp photography, in vivo confocal microscopy, angiography, and optical coherence tomography angiography (OCTA) are the primary diagnostic tools utilized in clinical practice to evaluate the vasculature of the ocular surface. However, there is currently a dearth of comprehensive literature that reviews the advancements in imaging technology for CoNV administration. Initially designed for retinal vascular imaging, OCTA has now been expanded to the anterior segment and has shown promising potential for imaging the conjunctiva, cornea, and iris. This expansion allows for the quantitative monitoring of the structural and functional changes associated with CoNV. In this review, we emphasize the impact of algorithm optimization in anterior segment-optical coherence tomography angiography (AS-OCTA) on the diagnostic efficacy of CoNV. Through the analysis of existing literature, animal model assessments are further reported to investigate its pathological mechanism and exhibit remarkable therapeutic interventions. In conclusion, AS-OCTA holds broad prospects and extensive potential for clinical diagnostics and research applications in CoNV.
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Affiliation(s)
- Yinuo Wen
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University; Key laboratory of Myopia and Related Eye Diseases, NHC; Key laboratory of Myopia and Related Eye Diseases, Chinese Academy of Medical Sciences, Shanghai, China; Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
| | - Zhongxing Chen
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University; Key laboratory of Myopia and Related Eye Diseases, NHC; Key laboratory of Myopia and Related Eye Diseases, Chinese Academy of Medical Sciences, Shanghai, China; Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
| | - Colm McAlinden
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University; Key laboratory of Myopia and Related Eye Diseases, NHC; Key laboratory of Myopia and Related Eye Diseases, Chinese Academy of Medical Sciences, Shanghai, China; Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China; Corneo Plastic Unit & Eye Bank, Queen Victoria Hospital, East Grinstead, UK
| | - Xingtao Zhou
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University; Key laboratory of Myopia and Related Eye Diseases, NHC; Key laboratory of Myopia and Related Eye Diseases, Chinese Academy of Medical Sciences, Shanghai, China; Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
| | - Jinhai Huang
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University; Key laboratory of Myopia and Related Eye Diseases, NHC; Key laboratory of Myopia and Related Eye Diseases, Chinese Academy of Medical Sciences, Shanghai, China; Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China.
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2
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Rangu N, Dang DH, Riaz KM. Current trends in the management of corneal neovascularization. Curr Opin Ophthalmol 2024; 35:329-342. [PMID: 38813739 DOI: 10.1097/icu.0000000000001049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
PURPOSE OF REVIEW The aim of this study was to highlight recent developments in the medical and surgical management of corneal neovascularization (NV). RECENT FINDINGS Improved understanding and diagnostic criteria among clinicians have led to advancements in the characterization of corneal NV and objective assessment of treatment response through ancillary imaging devices. Developments in corneal NV treatments, such as antivascular endothelial growth factor, fine needle diathermy, and photodynamic therapy, have improved treatment success rates and visual outcomes. More recent surgical treatment advancements include corneal cross-linking, endothelial keratoplasty, and mitomycin intravascular chemoembolization. Finally, a greater appreciation of the molecular pathogenesis and angiogenic factors involved in corneal NV has identified numerous potential targeted therapies in the future. SUMMARY The management of corneal NV has evolved to include several standalone and combination medical and surgical options. Additionally, improvements in quantifying corneal NV and understanding its molecular basis have contributed to new management strategies with improved outcomes.
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Affiliation(s)
- Neal Rangu
- Department of Ophthalmology, Dean McGee Eye Institute, University of Oklahoma Health Sciences Center
- College of Medicine, University of Oklahoma, Oklahoma City, Oklahoma, USA
| | - Deanna H Dang
- Department of Ophthalmology, Dean McGee Eye Institute, University of Oklahoma Health Sciences Center
| | - Kamran M Riaz
- Department of Ophthalmology, Dean McGee Eye Institute, University of Oklahoma Health Sciences Center
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3
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Aschauer J, Klimek M, Donner R, Lammer J, Roberts P, Schranz M, Schmidinger G. Non-invasive quantification of corneal vascularization using anterior segment optical coherence tomography angiography. Sci Rep 2024; 14:2124. [PMID: 38267485 PMCID: PMC10808211 DOI: 10.1038/s41598-024-52598-z] [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: 07/30/2023] [Accepted: 01/21/2024] [Indexed: 01/26/2024] Open
Abstract
The presence of corneal vascularization (CV) interferes with the angiogenic and immune privilege of the cornea, risking rejection in eyes following keratoplasty. Pre-operative (lymph)-angioregression is a promising therapeutic approach, but objective monitoring by non-invasive CV imaging is needed. The purpose of this study was to investigate anterior-segment optical coherence tomography angiography (AS-OCTA) for CV visualization and quantification, and to show its superiority over slit-lamp photography in high-risk eyes scheduled for keratoplasty. This institutional pilot study included 29 eyes of 26 patients (51 ± 16 years, 8 female) with significant CV scheduled for keratoplasty that were imaged by slit-lamp photography (Zeiss SL 800) and AS-OCTA (Zeiss Plex Elite 9000). After manual corneal layer segmentation correction, CV maximum/relative depth was measured with the inbuilt software. Slit-lamp photographs and AS-OCTA images were compared for visualization of vascular details. Angiotool software allowed a semi-automated determination of CV-related parameters in the vascular complex of AS-OCTA images. The predominant causes of CV were the herpes simplex virus keratitis (n = 7) and chemical burn (n = 4). Visualization of vascular morphology in AS-OCTA was superior to slit-lamp photography in all except one eye. Vascular metrics including total vessel length, number of junctions/endpoints, junction density, lacunarity, and vessel area/density were defined using Angiotool, with CV depth localization despite scarring and opacification. AS-OCTA proved effective for angioregressive treatment monitoring. AS-OCTA enables non-invasive and objective three-dimensional visualization of corneal vascularization superior to slit-lamp photography, and could be a precious tool for monitoring angioregressive preconditioning prior to keratoplasty.
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Affiliation(s)
- Julia Aschauer
- Department of Ophthalmology and Optometry, Medical University of Vienna, Spitalgasse 23, 1090, Vienna, Austria.
| | - Michal Klimek
- Department of Ophthalmology and Optometry, Medical University of Vienna, Spitalgasse 23, 1090, Vienna, Austria
| | - Ruth Donner
- Department of Ophthalmology and Optometry, Medical University of Vienna, Spitalgasse 23, 1090, Vienna, Austria
| | - Jan Lammer
- Department of Ophthalmology and Optometry, Medical University of Vienna, Spitalgasse 23, 1090, Vienna, Austria
| | - Philipp Roberts
- Department of Ophthalmology and Optometry, Medical University of Vienna, Spitalgasse 23, 1090, Vienna, Austria
| | - Markus Schranz
- Department of Ophthalmology and Optometry, Medical University of Vienna, Spitalgasse 23, 1090, Vienna, Austria
| | - Gerald Schmidinger
- Department of Ophthalmology and Optometry, Medical University of Vienna, Spitalgasse 23, 1090, Vienna, Austria
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4
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Wen Y, Jiang D, Tang K, Chen W. Current clinical applications of anterior segment optical coherence tomography angiography: a review. Graefes Arch Clin Exp Ophthalmol 2023; 261:2729-2741. [PMID: 36862203 DOI: 10.1007/s00417-023-05997-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 01/20/2023] [Accepted: 02/04/2023] [Indexed: 03/03/2023] Open
Abstract
Optical coherence tomography (OCT) is a revolutionary in vivo imaging technology that presents real-time information on ocular structures. Angiography based on OCT, known as optical coherence tomography angiography (OCTA), is a noninvasive and time-saving technique originally utilized for visualizing retinal vasculature. As devices and built-in systems have evolved, high-resolution images with depth-resolved analysis have assisted ophthalmologists in accurately localizing pathology and monitoring disease progression. With the aforementioned advantages, application of OCTA has extended from the posterior to anterior segment. This nascent adaptation showed good delineation of the vasculature in the cornea, conjunctiva, sclera, and iris. Thus, neovascularization of the avascular cornea and hyperemia or ischemic changes involving the conjunctiva, sclera, and iris has become prospective applications for AS-OCTA. Although traditional dye-based angiography is regarded as the gold standard in demonstrating vasculature in the anterior segment, AS-OCTA is expected to be a comparable but more patient-friendly alternative. In its initial stage, AS-OCTA has exhibited great potential in pathology diagnosis, therapeutic evaluation, presurgical planning, and prognosis assessments in anterior segment disorders. In this review of AS-OCTA, we aim to summarize scanning protocols, relevant parameters, and clinical applications as well as limitations and future directions. We are sanguine about its wide application in the future with the development of technology and refinement in built-in systems.
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Affiliation(s)
- Yajing Wen
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Dan Jiang
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Kexin Tang
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Wei Chen
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
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5
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Alasbali T. Current State of Knowledge in Ocular Blood Flow in Glaucoma: A Narrative Review. Clin Ophthalmol 2023; 17:2599-2607. [PMID: 37671333 PMCID: PMC10476666 DOI: 10.2147/opth.s426709] [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: 07/12/2023] [Accepted: 08/24/2023] [Indexed: 09/07/2023] Open
Abstract
Glaucoma is a multifactorial disease that is dependent on Intra Ocular Pressure (IOP) and associated with risk factors related to reduced ocular blood flow (OBF). In clinical practice, it is instrumental to update and review the considerable evidence of the current imaging technologies utilized in the investigation of OBF involved in both the onset and progression of glaucoma. Bibliographic databases, including PubMed and Google Scholar, were searched for articles on OBF techniques published between 2018 and 2023 using keywords such as "ocular blood flow", "glaucoma", "invasive ocular blood flow measurement", and "non-invasive ocular blood flow measurement". All types of methodologies were considered, except for editorials, letters to the editor, and animal studies. This review provides comprehensive information on the recent state-of-the-art imaging innovations used to monitor and measure the ocular blood flow in glaucoma.
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Affiliation(s)
- Tariq Alasbali
- Department of Ophthalmology, Faculty of Medicine, College of Medicine, Imam Mohammed Ibn Saud Islamic University, Riyadh, Saudi Arabia
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6
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Assessment of Corneal Angiography Filling Patterns in Corneal Neovascularization. J Clin Med 2023; 12:jcm12020633. [PMID: 36675562 PMCID: PMC9867460 DOI: 10.3390/jcm12020633] [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: 12/14/2022] [Revised: 01/04/2023] [Accepted: 01/09/2023] [Indexed: 01/15/2023] Open
Abstract
The purpose of the paper is to describe vascular filling patterns in corneal neovascularization (CoNV) and evaluate the effect of corneal lesion location, CoNV surface area and multi-quadrant CoNV involvement on the filling pattern. It is a retrospective study of patients who were investigated for CoNV using fluorescein angiography (FA) or indocyanine green angiography (ICGA) between January 2010 and July 2020. Angiography images were graded and analyzed multiple independent corneal specialists. The corneal surface was divided into four quadrants and patient information was obtained through electronic records. A total of 133 eyes were analyzed. Corneal lesions were located on the peripheral (72%) or central (28%) cornea. Central lesions were associated with multi-quadrant CoNV more frequently than peripheral lesions (p = 0.15). CoNV located within the same quadrant of the corneal lesion was often first to fill (88.4%). In multi-quadrant CoNV, the physiological inferior-superior-nasal-temporal order of filling was usually respected (61.7%). Central lesions resulted in larger CoNV surface area than peripheral lesions (p = 0.09). In multi-quadrant CoNV, the largest area of neovascularization was also the first to fill in (peripheral lesion 74%, central lesion 65%). Fillings patterns in healthy corneas have previously been reported. Despite CoNV development, these patterns are usually respected. Several factors that may influence filling patterns have been identified, including corneal lesion location, CoNV surface area and aetiology of CoNV. Understanding filling patterns of neovascularization allows for the identification of areas at higher risk of developing CoNV, aiding in earlier detection and intervention of CoNV.
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7
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Keshet Y, Polat A, Gal-Or O, Ben Ishai M, Keshet Y, Fradkin M, Schaap Fogler M, Megiddo Barnir E. Limbal-conjunctival autograft healing process-early postoperative OCT angiography study. Eye (Lond) 2022; 36:2151-2156. [PMID: 34725469 PMCID: PMC9581883 DOI: 10.1038/s41433-021-01827-0] [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: 11/16/2020] [Revised: 09/28/2021] [Accepted: 10/18/2021] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To assess the normal healing process of limbal-conjunctival autograft (LCA) after pterygium removal during the early postoperative period using anterior segment optical coherence tomography angiography (OCTA). METHODS Prospective case series of seven patients undergoing pterygium removal with LCA transplantation procedure, imaged with anterior segment OCTA, and anterior segment colour photos prior to the procedure and on postoperative day (POD) 1, 3, 7 and 30. Revascularization of the graft was analysed quantitatively and qualitatively to estimate patterns of blood vessel growth. Association between revascularization to graft thickness was also investigated. RESULTS On POD 1, all autografts showed either minimal flow signal or no signal at all (Mean 7.1 ± 3.3%). Regrowth of blood vessels into the graft was detected on OCTA scans on POD3 (8.7 ± 3.6%) to 7 (14.3 ± 4.1%), as nonorganised vessels formation in their appearance. Blood vessels were seen growing in a centrifugal pattern towards the surrounding conjunctiva, originating from the underlying episcleral vessels. Revascularization flow signal was seen throughout nearly all graft extent on day 30 (21.6 ± 2.2%). Graft oedema was evident on the first week (Mean 611 ± 120 μm, 695 ± 84 μm, 639 ± 96 μm of POD 1, 3 and 7, respectively), reducing substantially by day 30 (300 ± 108 μm). CONCLUSIONS OCTA imaging can be used to assess the LCA healing process during the early postoperative period. Revascularization occurring as early as 3-7 days post-surgery, seems to originate from the underlying episcleral vessels. Therefore, careful handling of the bare scleral surface during surgery may be prudent for achieving an adequate healing process.
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Affiliation(s)
- Yariv Keshet
- Department of Ophthalmology, Rabin Medical Center, Petach Tikva. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
| | - Asaf Polat
- Department of Ophthalmology, Rabin Medical Center, Petach Tikva. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Orly Gal-Or
- Department of Ophthalmology, Rabin Medical Center, Petach Tikva. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Meydan Ben Ishai
- Department of Ophthalmology, Rabin Medical Center, Petach Tikva. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yotam Keshet
- Department of Ophthalmology, Rabin Medical Center, Petach Tikva. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Maayan Fradkin
- Department of Ophthalmology, Rabin Medical Center, Petach Tikva. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Michal Schaap Fogler
- Department of Ophthalmology, Rabin Medical Center, Petach Tikva. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Elinor Megiddo Barnir
- Department of Ophthalmology, Rabin Medical Center, Petach Tikva. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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8
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Luisi J, Lin JL, Karediya N, Kraft ER, Sharifi A, Schmitz-Brown ME, Zhang W, Ameredes BT, Merkley KH, Motamedi M, Gupta PK. Concentration-associated pathology of alkali burn in a mouse model using anterior segment optical coherence tomography with angiography. Exp Eye Res 2022; 223:109210. [PMID: 35987418 DOI: 10.1016/j.exer.2022.109210] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 07/29/2022] [Accepted: 08/02/2022] [Indexed: 11/26/2022]
Abstract
Pathological features of alkali concentration-associated burn were studied using non-invasive anterior segment optical coherence tomography (AS-OCT) and OCT angiography (OCTA). Alkali burn was induced in C57BL/6J mice (n = 20) by placing filter paper soaked in 0.1, 0.25, 0.5, and 1 M NaOH for 30s on the right eye (left eye control). Longitudinal imaging was performed with AS-OCT/OCTA and fluorescein angiography over 14 days, after which eyes were enucleated at 7 and 14 days for histology and immunofluorescence. Concentration-associated corneal swelling was maximal at 0.5M, increasing linearly in a concentration-dependent fashion at 0.1, 0.25, and 0.5 M NaOH, to levels of 50%, 100%, and 175% of control, respectively. At 0.1M, corneal swelling and surface erosions were prominent, while at 0.25M, deep tissue damage, limbal neovascularization, and stromal haze were evident at 7 days. At 0.5M and 1M, severe exacerbation of the corneal swelling, angle closure, Descemet's membrane detachment, hyphema, and profuse central neovascularization were noted as early as day 3, which further progressed to inflammation, fibrosis, and opacity by day 7. We conclude that alkali concentration-dependent burn intensity biomarkers can be assessed by non-invasive AS-OCT/OCTA, distinguishing between mild, moderate, and severe ocular injury, with potential relevance toward clinical utilization in human eyes.
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Affiliation(s)
- Jonathan Luisi
- Departments of Internal Medicine and Pharmacology and Toxicology, United States; Department of Ophthalmology and Visual Sciences, United States
| | - Jonathan L Lin
- Departments of Internal Medicine and Pharmacology and Toxicology, United States
| | - Nishad Karediya
- Department of Ophthalmology and Visual Sciences, United States
| | - Edward R Kraft
- Department of Ophthalmology and Visual Sciences, United States
| | - Ardalan Sharifi
- Department of Ophthalmology and Visual Sciences, United States
| | | | - Wenbo Zhang
- Department of Ophthalmology and Visual Sciences, United States
| | - Bill T Ameredes
- Departments of Internal Medicine and Pharmacology and Toxicology, United States
| | - Kevin H Merkley
- Department of Ophthalmology and Visual Sciences, United States
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Beckmann L, Cai Z, Margolis M, Fang R, Djalilian A, Zhang HF. Recent advances in optical coherence tomography for anterior segment imaging in small animals and their clinical implications. Ocul Surf 2022; 26:222-233. [PMID: 36195237 PMCID: PMC10040227 DOI: 10.1016/j.jtos.2022.08.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 08/16/2022] [Accepted: 08/17/2022] [Indexed: 12/05/2022]
Abstract
Anterior segment optical coherence tomography (AS-OCT) is a rapidly evolving area of OCT imaging, providing high-resolution and non-invasive volumetric imaging of the anterior segment. This review focuses on recent advances in AS-OCT imaging in small animals, which we categorize into ultrahigh-resolution, spectroscopic, magnetomotive, polarization-sensitive, and angiographic AS-OCTs. We summarize their technical foundations, review their applications to small animal imaging, and briefly discuss their current and future clinical applications.
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Affiliation(s)
- Lisa Beckmann
- Department of Biomedical Engineering, Northwestern University, Evanston IL, USA
| | - Zhen Cai
- Department of Biomedical Engineering, Northwestern University, Evanston IL, USA; Currently with Department of Ophthalmology, Tongji Medical College, HuaZhong University of Science and Technology, Wuhan, Hubei, China
| | - Mathew Margolis
- Department of Ophthalmology and Visual Science, University of Illinois at Chicago, Chicago IL, USA
| | - Raymond Fang
- Department of Biomedical Engineering, Northwestern University, Evanston IL, USA
| | - Ali Djalilian
- Department of Ophthalmology and Visual Science, University of Illinois at Chicago, Chicago IL, USA
| | - Hao F Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston IL, USA.
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10
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Imaging of iris vasculature: current limitations and future perspective. Eye (Lond) 2022; 36:930-940. [PMID: 34650219 PMCID: PMC9046297 DOI: 10.1038/s41433-021-01809-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 08/22/2021] [Accepted: 10/01/2021] [Indexed: 12/22/2022] Open
Abstract
Fluorescein and indocyanine green angiography have been the traditional ways to image the vasculature of the iris in the last few decades. Because of the invasive nature of these procedures, they are performed in rare situations, and thus, our understanding about iris vasculature is very limited. Optical coherence tomography angiography (OCTA) is a noninvasive imaging method that enables the detailed visualization of the retinal and choroidal vascular networks. More recently, it has been also used for the examination of the iris vasculature in healthy and disease eyes. However, there is a lack of uniformity in the image acquisition protocols and interpretations in both healthy and pathological conditions. Artifacts of iris OCTA include shadowing, motion, segmentations errors, mirror effects. OCTA devices have an eye-tracking system designed for the posterior segment and the applications of these systems on the anterior segment can determine motion lines, vessel duplication, and vessel discontinuity. OCTA of the iris should always be performed under ambient room lighting to create miosis and reduce iris vasculature changes during the examination. In the near future, eye-tracking systems specifically designed for the iris vessels could permit the follow-up function, and the development of new OCTA metrics could reveal interesting applications of this new imaging technique.
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11
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Role of AS-OCT in Managing Corneal Disorders. Diagnostics (Basel) 2022; 12:diagnostics12040918. [PMID: 35453966 PMCID: PMC9030521 DOI: 10.3390/diagnostics12040918] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 11/17/2022] Open
Abstract
Optical coherence tomography (OCT) is analogous to ultrasound biometry in the cross sectional imaging of ocular tissues. Development of current devices with deeper penetration and higher resolution has made it popular tool in clinics for visualization of anterior segment structures. In this review, the authors discussed the application of AS-OCT for diagnosis and management of various corneal and ocular surface disorders. Further, recent developments in the application of the device for pediatric corneal disorders and extending the application of OCT angiography for anterior segment are introduced.
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12
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Kong M, Zhou T, Xiang B. Expression of the axon guidance factor Slit2 and its receptor Robo1 in patients with Hirschsprung disease: An observational study. Medicine (Baltimore) 2021; 100:e26981. [PMID: 34414975 PMCID: PMC8376357 DOI: 10.1097/md.0000000000026981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 07/12/2021] [Accepted: 07/27/2021] [Indexed: 02/05/2023] Open
Abstract
ABSTRACT Hirschsprung disease (HD) is a common form of digestive tract malformation in children. However, the pathogenesis of HD is not very clear. This study aimed to investigate the expression of slit guidance ligand 2 (Slit2) and roundabout 1 (Robo1) in patients with HD.From January 2018 to January 2019, 30 colon specimens from children with HD undergoing surgical resection at the Department of Surgery in Qilu Children's Hospital of Shandong University were obtained. These specimens were divided into the normal segment group, the transitional segment group and the spastic segment group. Immunohistochemical staining, Western blotting, and real-time polymerase chain reaction were used to measure the expression of Slit2 and Robo1 in the intestinal walls of normal, transitional, and spastic segments.Immunohistochemical staining and Western blot analyses showed high levels of the Slit2 and Robo1 proteins in normal ganglion cells in children with HD, lower levels in transitional ganglion cells, and no expression in spastic segments, with significant differences between groups (P < .05). Similarly, the real-time polymerase chain reaction results were consistent with the Western blot analysis results.The expression of Slit2 and Robo1 decreases significantly in the spastic segment of the intestinal tract in patients with HD.
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Affiliation(s)
- Meng Kong
- Department of Pediatric Surgery, Qilu Children's Hospital of Shandong University, Jinan, China
| | - Tao Zhou
- Department of Pediatric Surgery, Dazhou Central Hospital, Dazhou, China
| | - Bo Xiang
- Department of Pediatric Surgery, West China Hospital of Sichuan University, Chengdu, China
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13
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Tey KY, Gan J, Foo V, Tan B, Ke MY, Schmetterer L, Mehta JS, Ang M. Role of anterior segment optical coherence tomography angiography in the assessment of acute chemical ocular injury: a pilot animal model study. Sci Rep 2021; 11:16625. [PMID: 34404833 PMCID: PMC8371111 DOI: 10.1038/s41598-021-96086-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 07/21/2021] [Indexed: 11/28/2022] Open
Abstract
To examine the use of anterior segment-optical coherence tomography angiography (AS-OCTA) in the assessment of limbal ischemia in an animal model chemical ocular injury. We conducted a prospective study using an established chemical ocular injury model in 6 rabbits (12 eyes), dividing the cornea limbus into 4 quadrants. Chemical injury grade was induced based on extent of limbal injury (0 to 360 degrees) and all eyes underwent serial slit-lamp with AS-OCTA imaging up to one month. Main outcome measure was changes in AS-OCTA vessel density (VD) comparing injured and control cornea limbal quadrants within 24 h and at one month. AS-OCTA was able to detect differences in limbal VD reduction comparing injured (3.3 ± 2.4%) and control quadrants (7.6 ± 2.3%; p < 0.001) within 24 h of ocular chemical injury. We also observed that AS-OCTA VD reduction was highly correlated with the number of quadrants injured (r = − 0.89; p < 0.001; 95% CI − 5.65 to − 1.87). Corneal vascularization was detected by AS-OCTA in injured compared to control quadrants (10.1 ± 4.3% vs 7.0 ± 1.2%; p = 0.025) at 1 month. Our animal pilot study suggests that AS-OCTA was able to detect limbal vessel disruption from various severities of acute chemical insult, and in the future, could potentially serve as an adjunct in providing objective grading of acute ocular chemical injury once validated in a clinical trial.
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Affiliation(s)
- Kai Yuan Tey
- Singapore Eye Research Institute, Singapore, Singapore
| | - Jinyuan Gan
- Duke-NUS Medical School, Singapore, Singapore
| | - Valencia Foo
- Singapore National Eye Centre, 20 College Rd, Singapore, 169856, Singapore
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE) Program, Nanyang Technological University, Singapore, Singapore
| | - Meng Yuan Ke
- Singapore Eye Research Institute, Singapore, Singapore
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore, Singapore.,Duke-NUS Medical School, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE) Program, Nanyang Technological University, Singapore, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore.,Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Jodhbir S Mehta
- Singapore Eye Research Institute, Singapore, Singapore.,Duke-NUS Medical School, Singapore, Singapore.,Singapore National Eye Centre, 20 College Rd, Singapore, 169856, Singapore
| | - Marcus Ang
- Singapore Eye Research Institute, Singapore, Singapore. .,Duke-NUS Medical School, Singapore, Singapore. .,Singapore National Eye Centre, 20 College Rd, Singapore, 169856, Singapore.
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Foo VHX, Ke M, Tan CQL, Schmetterer L, Mehta JS, Ang M. Anterior Segment Optical Coherence Tomography Angiography Assessment of Corneal Vascularisation After Combined Fine-Needle Diathermy with Subconjunctival Ranibizumab: A Pilot Study. Adv Ther 2021; 38:4333-4343. [PMID: 34241779 DOI: 10.1007/s12325-021-01849-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 06/25/2021] [Indexed: 11/29/2022]
Abstract
INTRODUCTION To describe anterior segment optical coherence tomography angiography (AS-OCTA) imaging to monitor corneal vascularisation (CoNV) and scar reduction after combined fine-needle diathermy (FND) with subconjunctival ranibizumab. METHODS Prospective clinical study of six eyes from six subjects with corneal scar and CoNV which underwent combined FND with subconjunctival ranibizumab. All eyes were imaged using slit-lamp photography (SLP) and AS-OCTA (Optovue, Inc., Fremont, CA, wavelength: 840 nm) before and after the operation, with two independent masked assessors analysing all images. Main outcome measures were changes in median corneal scar area and vessel density (AS-OCTA) comparing pre- and postoperative imaging up to month 3 and 6. RESULTS The mean age of the subjects was 60 ± 23 years, with three males and three females. CoNV and corneal scarring involving the visual axis were present in all eyes, secondary to previous infective keratitis (n = 3), severe blepharokeratoconjunctivitis (n = 2), or chemical injury (n = 1). Follow-up time frame ranged from 2 to 6 months postoperation. There was a reduction in median corneal scar area from 30.2 mm2 (IQR 18.7-38.5) before surgery to 14.8 mm2 (IQR 7.1-19.6) after surgery, with a median reduction of 37.1% (IQR = - 3.1-86.9, p = 0.046). There was also a reduction in median cornea vessel density (AS-OCTA) from 20.8% (IQR 16.1-20.8) before surgery to 17.6% (IQR 14.0-17.6) after surgery, with a median reduction of 15.1% (IQR 13.2-15.1, p < 0.001). CONCLUSIONS Combined imaging of SLP and AS-OCTA is useful for monitoring treatment response of corneal scarring and CoNV after combined FND with subconjunctival Ranibizumab.
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Affiliation(s)
- Valencia Hui Xian Foo
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
| | - Mengyuan Ke
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
| | - Chelsea Qiu Lin Tan
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Leopold Schmetterer
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Department of Ophthalmology and Visual Science, Duke-NUS Graduate Medical School, 8 College Road, Singapore, 169857, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), 50 Nanyang Drive, Singapore, 637553, Singapore
- Institute for Health Technologies, Nanyang Technological University, 50 Nanyang Drive, Singapore, 637553, Singapore
- Department of Clinical Pharmacology, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Institute of Clinical and Experimental Ophthalmology, Klybeckstrasse 141, WKL 420, 4057, Basel, Switzerland
| | - Jodhbir S Mehta
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Department of Ophthalmology and Visual Science, Duke-NUS Graduate Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Marcus Ang
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore.
- Department of Ophthalmology and Visual Science, Duke-NUS Graduate Medical School, 8 College Road, Singapore, 169857, Singapore.
- Department of Ophthalmology and Visual Sciences, Duke-NUS Medical School, Cornea and Refractive Service, Singapore National Eye Center, 11 Third Hospital Avenue, Singapore, 168751, Singapore.
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