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Yamamoto N, Nakano M, Nochioka K, Yasuda M, Kunikata H, Nakazawa T, Yasuda S. Ocular blood flow dynamics following sinus rhythm restoration through catheter ablation: laser speckle flowgraphy in patients with persistent atrial fibrillation. EUROPEAN HEART JOURNAL. IMAGING METHODS AND PRACTICE 2024; 2:qyae071. [PMID: 39224622 PMCID: PMC11367941 DOI: 10.1093/ehjimp/qyae071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Accepted: 06/05/2024] [Indexed: 09/04/2024]
Abstract
Aims Laser speckle flowgraphy (LSFG) is a well-established tool renowned for its non-invasive and reproducible assessment of ocular blood flow. While rhythm control therapies, such as catheter ablation (CA), have shown promise in enhancing cognitive function in atrial fibrillation (AF) patients, the acute impact of CA on microcirculatory changes, particularly in ocular blood flow, remains a topic of limited understanding. The present study aims to delve into the potential of LSFG in detecting microcirculatory alterations following the restoration of sinus rhythm (SR) through CA in patients with AF. Methods and results We studied 8 paroxysmal AF (Paf) and 20 persistent AF (PeAF) patients (mean age 67 ± 6 years, 26% female) undergoing CA. Ocular blood flow was assessed using LSFG by measuring the mean blur rate (MBR) pre- and post-CA. Post-CA, all PeAF patients achieved SR restoration, resulting in a significant increase in tissue MBR (10.0 ± 2.2 to 10.8 ± 2.9, P = 0.021). In contrast, Paf patients showed no significant difference between pre- and post-MBR (12.0 ± 2.7 vs. 11.8 ± 2.6, P = 0.76). Conclusion LSFG analysis effectively identified microcirculatory changes in patients undergoing CA for PeAF, suggesting that therapeutic interventions targeting the heart may have broader implications for ocular and cerebral health, establishing a novel 'cardio-oculo-cerebral relationship'.
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Affiliation(s)
- Nobuhiko Yamamoto
- Departments of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, 1-1, Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan
| | - Makoto Nakano
- Departments of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, 1-1, Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan
| | - Kotaro Nochioka
- Departments of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, 1-1, Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan
| | - Masayuki Yasuda
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hiroshi Kunikata
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Toru Nakazawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Satoshi Yasuda
- Departments of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, 1-1, Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan
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Silverman RH, Urs R, Wapner RJ, Valenzuela IA, Coleman HR, Bearelly S. Correlation of Ocular Plane-Wave Doppler With Optical Coherence Tomography Angiography in Preeclampsia. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2023; 42:2815-2824. [PMID: 37605863 PMCID: PMC10840834 DOI: 10.1002/jum.16320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/02/2023] [Accepted: 08/06/2023] [Indexed: 08/23/2023]
Abstract
OBJECTIVES Preeclampsia (PE) is a severe complication of pregnancy characterized by hypertension, proteinuria and compromised fetal blood supply. The eye, like other end organs, is affected by this systemic condition, but unlike in other organs, ocular media transparency allows high-resolution optical visualization of the vascular structure of the retina. Our aim was to assess how ultrasound-determined ocular blood-flow correlates with vascular structure of the retina and choriocapillaris determined by optical coherence tomography angiography (OCTA). METHODS Plane-wave ultrasound and OCTA were performed on both eyes of 40 consecutive subjects consisting of normal controls (n = 11), mild PE (n = 5), severe PE (n = 17) and chronic or gestational hypertension (n = 7) within 72 hours following delivery. From ultrasound, we measured pulsatile flow velocity and resistance indices in the central retinal artery (CRA) and vein, the short posterior ciliary arteries (SPCAs) and choroid. From OCTA, we measured vascular density (VD) in the superficial, deep retina and choriocapillaris. We determined differences in Doppler and OCTA parameters among groups and correlations between ultrasound and OCTA. RESULTS In severe PE, flow resistance was reduced with respect to controls. Flow velocity and resistance in the and SPCA were moderately correlated with VD in the choriocapillaris and peripapillary retina, but VD in PE did not differ significantly from controls. CONCLUSIONS Although OCTA parameters were moderately correlated with Doppler ultrasound, OCTA did not demonstrate significant differences between PE and controls postpartum.
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Affiliation(s)
| | - Raksha Urs
- Department of Ophthalmology, Columbia University Irving Medical Center
| | - Ronald J. Wapner
- Department of Obstetrics and Gynecology, Columbia University Irving Medical Center
| | | | - Hanna R. Coleman
- Department of Ophthalmology, Columbia University Irving Medical Center
| | - Srilaxmi Bearelly
- Department of Ophthalmology, Columbia University Irving Medical Center
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Okamoto K, Takahashi N, Kobayashi T, Shiba T, Hori Y, Fujii H. Novel superpixel method to visualize fundus blood flow resistivity in healthy adults. Sci Rep 2023; 13:6171. [PMID: 37061579 PMCID: PMC10105763 DOI: 10.1038/s41598-023-33450-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 04/13/2023] [Indexed: 04/17/2023] Open
Abstract
We aimed to perform superpixel segmentation of ocular blood flow maps obtained using laser speckle flowgraphy (LSFG) and investigate the effects of systemic parameters such as body weight, height, and sex on ocular blood flow resistivity. We studied 757 healthy participants (583 men, 174 women). We calculated the average beat strength over mean blur rate (BOM) as a LSFG resistivity index, as a function of age and sex using ordinary regions of interest (ROI) centered on the optic nerve head (ONH), the retinal vessels region and tissue around the ONH, and the choroid (CHD). We compared the ROI and superpixel-based methods, which are segmented based on image processing, for calculating the BOM. The sex differences in the BOM for the ONH, retinal-vessels region and tissue region of the ONH and CHD were significant for individuals aged ≤ 50 years (P < 0.01) but not those > 50 years old (P > 0.05). The average BOMs calculated using the ROI and superpixel methods were strongly correlated in the ONH (coefficient = 0.87, R2 = 0.8, P < 0.0001, n = 5465). In summary, a superpixel-segmented BOM map is suitable for two-dimensional visualization of ocular blood flow resistivity.
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Affiliation(s)
| | | | - Tatsuhiko Kobayashi
- Department of Ophthalmology, School of Medicine, Toho University, Tokyo, Japan
- Department of Ophthalmology, International University of Health and Welfare Narita Hospital, Chiba, Japan
| | - Tomoaki Shiba
- Department of Ophthalmology, International University of Health and Welfare Narita Hospital, Chiba, Japan
| | - Yuichi Hori
- Department of Ophthalmology, School of Medicine, Toho University, Tokyo, Japan
| | - Hitoshi Fujii
- Softcare Co., Ltd., Fukutsu, Japan
- Department of Computer Science and Electronics, Kyushu Institute of Technology, Iizuka, Fukuoka, Japan
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Böhm EW, Pfeiffer N, Wagner FM, Gericke A. Methods to measure blood flow and vascular reactivity in the retina. Front Med (Lausanne) 2023; 9:1069449. [PMID: 36714119 PMCID: PMC9877427 DOI: 10.3389/fmed.2022.1069449] [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: 10/13/2022] [Accepted: 12/23/2022] [Indexed: 01/14/2023] Open
Abstract
Disturbances of retinal perfusion are involved in the onset and maintenance of several ocular diseases, including diabetic retinopathy, glaucoma, and retinal vascular occlusion. Hence, knowledge on ocular vascular anatomy and function is highly relevant for basic research studies and for clinical judgment and treatment. The retinal vasculature is composed of the superficial, intermediate, and deep vascular layer. Detection of changes in blood flow and vascular diameter especially in smaller vessels is essential to understand and to analyze vascular diseases. Several methods to evaluate blood flow regulation in the retina have been described so far, but no gold standard has been established. For highly reliable assessment of retinal blood flow, exact determination of vessel diameter is necessary. Several measurement methods have already been reported in humans. But for further analysis of retinal vascular diseases, studies in laboratory animals, including genetically modified mice, are important. As for mice, the small vessel size is challenging requiring devices with high optic resolution. In this review, we recapitulate different methods for retinal blood flow and vessel diameter measurement. Moreover, studies in humans and in experimental animals are described.
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Ebuchi Y, Nagaoka T, Fukamachi D, Kojima K, Akutsu N, Murata N, Saito Y, Kitano D, Yokota H, Yamagami S, Okumura Y. Comprehensive assessment of systemic arteriosclerosis in relation to the ocular resistive index in acute coronary syndrome patients. Sci Rep 2022; 12:2321. [PMID: 35149710 PMCID: PMC8837772 DOI: 10.1038/s41598-021-04196-6] [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: 04/25/2021] [Accepted: 10/20/2021] [Indexed: 11/13/2022] Open
Abstract
This study aimed to investigate the relationship between ocular vascular resistance parameters, evaluated by laser speckle flowgraphy (LSFG), and systemic atherosclerosis, renal parameters and cardiac function in acute coronary syndrome (ACS) patients. We evaluated 53 ACS patients between April 2019 and September 2020. LSFG measured the mean blur rate (MBR) and ocular blowout time (BOT) and resistivity index (RI). 110 consequent patients without a history of coronary artery disease who visited ophthalmology as a control group. Significant positive correlations were observed between ocular RI and systemic parameters in ACS patients, including intima-media thickness (r = 0.34, P = 0.015), brachial-ankle pulse-wave velocity (r = 0.41, P = 0.002), cystatin C (r = 0.32, P = 0.020), and E/e’ (r = 0.34, P = 0.013). Ocular RI was significantly higher in the ACS group than in the control group in male in their 40 s (0.37 ± 0.02 vs. 0.29 ± 0.01, P < 0.001) and 50 s (0.36 ± 0.02 vs. 0.30 ± 0.01, P = 0.01). We found that the ocular RI was associated with systemic atherosclerosis, early renal dysfunction, and diastolic cardiac dysfunction in ACS patients, suggesting that it could be a useful non-invasive comprehensive arteriosclerotic marker.
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Affiliation(s)
- Yasunari Ebuchi
- Division of Cardiology, Nihon University Itabashi Hospital, Tokyo, Japan
| | - Taiji Nagaoka
- Division of Ophthalmology, Nihon University Itabashi Hospital, Ohyaguchi-kamicho, Itabashi-ku, Tokyo, 173-8610, Japan.
| | - Daisuke Fukamachi
- Division of Cardiology, Nihon University Itabashi Hospital, Tokyo, Japan
| | - Keisuke Kojima
- Division of Cardiology, Nihon University Itabashi Hospital, Tokyo, Japan
| | - Naotaka Akutsu
- Division of Cardiology, Nihon University Itabashi Hospital, Tokyo, Japan
| | - Nobuhiro Murata
- Division of Cardiology, Nihon University Itabashi Hospital, Tokyo, Japan
| | - Yuki Saito
- Division of Cardiology, Nihon University Itabashi Hospital, Tokyo, Japan
| | - Daisuke Kitano
- Division of Cardiology, Nihon University Itabashi Hospital, Tokyo, Japan
| | - Harumasa Yokota
- Division of Ophthalmology, Nihon University Itabashi Hospital, Ohyaguchi-kamicho, Itabashi-ku, Tokyo, 173-8610, Japan
| | - Satoru Yamagami
- Division of Ophthalmology, Nihon University Itabashi Hospital, Ohyaguchi-kamicho, Itabashi-ku, Tokyo, 173-8610, Japan
| | - Yasuo Okumura
- Division of Cardiology, Nihon University Itabashi Hospital, Tokyo, Japan
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Abu El‐Asrar AM, Alsarhani W, Alzubaidi A, Gikandi PW. Effect of immunosuppressive therapy on ocular blood flow in initial-onset acute uveitis associated with Vogt-Koyanagi-Harada disease. Acta Ophthalmol 2021; 99:e1405-e1414. [PMID: 33719161 DOI: 10.1111/aos.14842] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 02/23/2021] [Indexed: 11/26/2022]
Abstract
PURPOSE To investigate the effect of immunosuppressive therapy on blood flow and waveform parameters in the choroid and optic nerve head (ONH) in patients with initial-onset acute uveitis associated with Vogt-Koyanagi-Harada (VKH) disease. METHODS In this prospective study, 18 patients (36 eyes) were studied. Laser speckle flowgraphy was performed at baseline and at 4 weeks, 8 weeks and 12 weeks after treatment. We analysed longitudinal changes in mean blur rate (MBR), blow-out time, blow-out score (BOS), acceleration time index (ATI), flow acceleration index (FAI), resistivity index (RI) and blood flow fluctuation. RESULTS After immunosuppressive therapy, MBR, representing blood flow velocity, in the choroid and ONH significantly increased at each post-treatment time point compared to baseline values. Among the analysed pulse waveform parameters, BOS significantly increased, while RI and fluctuation significantly decreased. Increased BOS and decreased RI indicate decreased vascular resistance following treatment. There was a strong negative correlation between BOS and RI. Additionally, FAI increased in the choroid and ATI increased in ONH. CONCLUSIONS Immunosuppressive therapy in the acute uveitic phase of VKH disease improved inflammation-related impairment in choroidal and ONH blood flow.
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Affiliation(s)
- Ahmed M. Abu El‐Asrar
- Department of Ophthalmology College of Medicine King Saud University Riyadh Saudi Arabia
- Dr. Nasser Al‐Rashid Research Chair in Ophthalmology College of Medicine King Saud University Riyadh Saudi Arabia
| | - Waleed Alsarhani
- Department of Ophthalmology College of Medicine King Saud University Riyadh Saudi Arabia
| | - Abdullah Alzubaidi
- Department of Ophthalmology College of Medicine King Saud University Riyadh Saudi Arabia
| | - Priscilla W. Gikandi
- Department of Ophthalmology College of Medicine King Saud University Riyadh Saudi Arabia
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Liu C, Wei P, Li J. The thickness changes of retina in high myopia patients during the third trimester of pregnancy: a pilot study. BMC Ophthalmol 2021; 21:382. [PMID: 34706696 PMCID: PMC8549153 DOI: 10.1186/s12886-021-02137-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 09/28/2021] [Indexed: 12/04/2022] Open
Abstract
Objectives To observe and compare the difference in retinal thickness using optical coherence tomography (OCT) between patients with high myopia (HM) during the third trimester of pregnancy and age-matched HM non-pregnant women. Methods A case-control study. A total of 39 eyes from 39 HM women in the third trimester (study group) and 50 eyes of 50 age-matched non-pregnant women with HM (control group) were included. All subjects underwent SD-OCT examination. The built-in software was used to measure the retinal thickness in macular region. The data from two groups were compared using independent-samples t test. Results Among the 89 subjects in this study, the mean gestational age of the study group was 35.09 ± 2.44 weeks, and the average age was 32.24 ± 3.75 years. The average age of the control group was 34.04 ± 7.19 years old. Compared with the control group, the average thickness of parafoveal area, and the average thickness of parafoveal superior, inferior, temporal quadrants of the superficial retina and the average thickness of the foveal and parafoveal of the superficial retina were significantly decreased in the study group (P < 0.05). Compared with the control group, the average thickness of all quadrants of the retina in the parafoveal area except the nasal quadrant were significantly decreased in the study group (P < 0.05). Conclusions In this observational study, the retinal thickness of patients with high myopia during the third trimester of pregnancy was thinner than that of non-pregnant women with age-matched high myopia.
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Affiliation(s)
- Chenchen Liu
- Department of Ophthalmology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China
| | - Puying Wei
- Department of Ophthalmology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China
| | - Jun Li
- Department of Ophthalmology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China.
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Sharifizad M, Schmidl D, Werkmeister RM, Zeisler H, Told R, Binder J, Küssel L, Garhöfer G, Schmetterer L. Retinal vessel diameters, flicker-induced retinal vasodilation and retinal oxygen saturation in high- and low-risk pregnancy. Acta Ophthalmol 2021; 99:628-636. [PMID: 33326186 PMCID: PMC8519143 DOI: 10.1111/aos.14696] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 11/10/2020] [Indexed: 01/12/2023]
Abstract
Purpose To compare retinal vascular parameters between high‐risk and low‐risk pregnant women over time during pregnancy. Methods In a longitudinal study, we included pregnant women with normal blood pressure and normal body mass index (BMI, group 1), pregnant women with systemic hypertension and/or overweight (group 2) and age‐matched nonpregnant healthy women (group 3). Using the dynamic vessel analyser (DVA) we investigated flicker‐induced vasodilation in retinal arteries (FLA) and veins (FLV), central retinal arterial and vein equivalent (CRAE, CRVE), arterio‐venous ratio (AVR) and retinal arterial and venous oxygen saturation (SartO2, SveinO2). Study visits were scheduled 2nd trimester (TP 2), 3rd trimester (TP 3) and postpartum (PP). Results Data from 29 women in group 1, 25 women in group 2 and 33 women in group 3 were included for analysis. FLA, FLV, CRAE, CRVE, AVR and SveinO2 were altered in group 2 (p‐values between < 0.001 and 0.009). At TP 3 the differences between groups were most pronounced. In contrast, there were only minor differences between group 1 and 3. Changes in retinal parameters were independently associated with systemic blood pressure and BMI. Conclusions The present analysis indicates that flicker‐induced retinal vasodilation, retinal vessel diameters and retinal oxygen saturation are altered in high‐risk pregnant women. Hence, these parameters are candidate biomarkers for pregnancy complications, a hypothesis that deserves further study.
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Affiliation(s)
- Mozhgan Sharifizad
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | - René M. Werkmeister
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
| | - Harald Zeisler
- Department of Obstetrics and Gynecology Medical University of Vienna Vienna Austria
| | - Reinhard Told
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
- Department of Ophthalmology Medical University of Vienna Vienna Austria
| | - Julia Binder
- Department of Obstetrics and Gynecology Medical University of Vienna Vienna Austria
| | - Lorenz Küssel
- Department of Obstetrics and Gynecology Medical University of Vienna Vienna Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
- Singapore Eye Research Institute Singapore Singapore
- School of Chemical and Biomedical Engineering Nanyang Technological University Singapore Singapore
- SERI‐NTU Advanced Ocular Engineering (STANCE) Singapore Singapore
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Tamplin MR, Broadhurst KA, Vitale AH, Hashimoto R, Kardon RH, Grumbach IM. Longitudinal Testing of Retinal Blood Flow in a Mouse Model of Hypertension by Laser Speckle Flowgraphy. Transl Vis Sci Technol 2021; 10:16. [PMID: 34003901 PMCID: PMC7884297 DOI: 10.1167/tvst.10.2.16] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Purpose The purpose of this study was to investigate the applicability of laser speckle flowgraphy (LSFG) for a longitudinal study of blood flow parameters in mice before, during, and after continuous infusion of angiotensin-II. Methods Normotensive C57BL/6J mice were imaged by LSFG at one (n = 22) or three sessions (n = 10). Two additional cohorts were imaged by LSFG before, during, and after continuous infusion of angiotensin-II by minipump for 2 or 4 weeks (n = 6 and 8, respectively). Retinal blood flow, vascular resistance, and total area of retinal vascular flow, a surrogate of vascular remodeling and vasoconstriction, were determined at each time point. Results During infusion of angiotensin-II for 2 weeks, decreased retinal blood flow and area of vascular flow, as well as increased vascular resistance, were observed. These changes were reversed 1 week after the end of angiotensin-II infusion. In mice infused with angiotensin-II for 4 weeks, decreased retinal blood flow and increased vascular resistance persisted at 6 weeks postinfusion, despite a decrease in blood pressure. Conclusions Arterial hypertension, induced by continuous angiotensin-II infusion, results in reduced retinal blood flow, increased vascular resistance, and decrease in area of intravascular blood flow within retinal arterioles and venules. Sustained vasoconstriction 6 weeks after the end of a 4-week period of angiotensin-II infusion may indicate vascular remodeling after a period of chronic hypertension. Translational Relevance Retinal LSFG is useful for serial investigation of blood flow in mouse models and provides a novel approach for translational studies on the microvascular effects of hypertension in vivo.
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Affiliation(s)
- Michelle R Tamplin
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Kimberly A Broadhurst
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Anthony H Vitale
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Ryuya Hashimoto
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Randy H Kardon
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Iowa City Veterans Affairs Healthcare System, Iowa City, IA, USA
| | - Isabella M Grumbach
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Iowa City Veterans Affairs Healthcare System, Iowa City, IA, USA
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10
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Hepokur M, Gönen B, Hamzaoğlu K, Tüten A, Sarici AM. Investigation of Retinal Vascular Changes during Pregnancy Using Optical Coherence Tomography Angiography. Semin Ophthalmol 2021; 36:19-27. [PMID: 33566739 DOI: 10.1080/08820538.2021.1884268] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Purpose: To investigate retinal vascular changes in pregnant women using optical coherence tomography angiography (OCTA).Materials and Methods: This prospective, cross-sectional study included 97 pregnant women and age-matched 34 healthy control subjects. The OCTA parameters of one eye (left) of pregnancy group and control group were compared. Besides, the OCTA parameters of three trimesters were compared between themselves and the control group. The foveal avascular zone (FAZ) area and the vessel density percentages of the superficial capillary plexus (SCP), deep capillary plexus (DCP), and radial peripapillary capillary (RPC) of all the groups were evaluated by OCTA.Results: In the pregnancy group, the vessel density of DCP was higher in all regions than the control group except the foveal region, but this difference could not reach statistical significance. On the other hand, the vessel density of SCP in the pregnancy group did not show a manifest change in all regions except the foveal region as in DCP. Although the FAZ area was wider in pregnancy group, this difference was not statistically significant (p:0.661). There was no statistically significant difference observed in vessel density of SCP, DCP, and RPC between the different trimesters and the control group, and none of these data correlated with the gestational week.Conclusion: This study showed retinal vascular changes secondary to pregnancy, especially in the vessel density of DCP. These results can provide information that should be taken into account in the evaluation and investigation of pregnancy-specific retinal vascular pathologies.
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Affiliation(s)
- Mustafa Hepokur
- Department of Ophthalmology, Istanbul Medeniyet University Göztepe Training and Research Hospital, Istanbul, Turkey
| | - Busenur Gönen
- Department of Ophthalmology, Istanbul University-Cerrahpaşa Faculty of Medicine, Istanbul, Turkey
| | - Kübra Hamzaoğlu
- Department of Obstetrics and Gynecology, Istanbul University-Cerrahpaşa Faculty of Medicine, Istanbul, Turkey
| | - Abdullah Tüten
- Department of Obstetrics and Gynecology, Istanbul University-Cerrahpaşa Faculty of Medicine, Istanbul, Turkey
| | - Ahmet Murat Sarici
- Department of Ophthalmology, Istanbul University-Cerrahpaşa Faculty of Medicine, Istanbul, Turkey
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Yildirim A, Kurt E, Altinisik M, Uyar Y. Evaluation of retinochoroidal tissues in third trimester pregnants: An optical coherence tomography angiography study. Eur J Ophthalmol 2020; 32:501-507. [PMID: 33081497 DOI: 10.1177/1120672120966566] [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] [Indexed: 11/15/2022]
Abstract
INTRODUCTION The structural and vascular changes in the retina and choroid in women in the third trimester of pregnancy were analyzed using optical coherence tomography angiography (OCTA). METHODS Forty women in the third trimester of uncomplicated pregnancy and 40 age-matched healthy women were included. Vascular density (VD) in the superficial and deep capillary plexuses (SCP/DCP), foveal density (FD), and foveal avascular zone (FAZ) area and perimetry measured with OCTA, as well as OCT measurements of central macular thickness (CMT) and choroidal thickness (CT) were compared between the groups. Correlations between structural OCT parameters and vascular OCTA metrics were analyzed. RESULTS The mean gestational age was 34 (28-41) weeks. Mean age was comparable in the groups (p = 0.732). The pregnant women had significantly higher parafoveal DCP-VD (p = 0.015), FAZ area (p = 0.044), and FD (p = 0.002). Mean subfoveal CT was 21 µm higher in pregnant women but was not significant (p = 0.472). There was no difference in CMT (p = 0.448). FAZ metrics were positively correlated with CT in pregnants and with CMT in the control group (p < 0.05). Parafoveal VD was negatively correlated with CT in the control group (p < 0.05). After adjusting for CT and CMT, the significant difference in VD and FD persisted (p < 0.05), while the difference in FAZ area lost significance (p > 0.05). CONCLUSIONS Considering the effects of the probable covariant factors CMT and CT, systemic changes in pregnant women in their third trimester may cause an increase in VD in the macula and parafoveal DCP.
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Affiliation(s)
| | - Emin Kurt
- Ophthalmology Department, Manisa Celal Bayar University, Manisa, Turkey
| | | | - Yildiz Uyar
- Obstetrics and Gynecology Department, Manisa Celal Bayar University, Manisa, Turkey
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Yata K, Hashimoto R, Masahara H, Oyamada M, Maeno T. Changes in choroidal circulation and pulse waveform in a case of pregnancy-induced hypertension with serous retinal detachment. Am J Ophthalmol Case Rep 2020; 20:100911. [PMID: 32964170 PMCID: PMC7490735 DOI: 10.1016/j.ajoc.2020.100911] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 08/01/2020] [Accepted: 08/31/2020] [Indexed: 10/25/2022] Open
Abstract
Purpose We aimed to examine the changes in choroidal blood flow (CBF), choroidal pulse waveform, and central choroidal thickness (CCT) in a case of pregnancy-induced hypertension (PIH) using laser speckle flowgraphy (LSFG) and enhanced depth imaging optical coherence tomography (EDI-OCT) before and after treatment with antihypertensive drugs. Observations A 24-year-old Japanese woman diagnosed with PIH presented with complaints of worsening and blurred vision in the right eye. Funduscopic findings at the initial visit showed serous retinal detachment (SRD), retinal hemorrhage, and arterial tortuosity. The LSFG color map showed a warm color. Macular mean blur rate (MBR), which is an index of relative blood flow velocity, in both eyes was high, along with choroidal thickening. Blowout time (BOT), which indicates the rate of time in which the MBR is greater than half the amplitude during one heartbeat, was low and acceleration time index (ATI), which represents the time-to-peak of MBR, was high. Several weeks after treatment with antihypertensive drugs, the CBF and ATI gradually decreased with regression of the SRD and thinning of the CCT. On the other hand, BOT gradually increased after treatment, showing a significant decrease in vascular resistance. Ocular perfusion pressure decreased after treatment because of the reduction in blood pressure. Conclusions and Importance LSFG might reveal choroidal overperfusion and increased vascular resistance, along with SRD and choroidal thickening, in a patient with PIH with reversal after treatment with antihypertensive drugs. These findings demonstrate the importance of evaluation of ocular blood flow and vascular resistance in women with PIH in order to routinely assess the clinical and systemic condition.
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Affiliation(s)
- Keisuke Yata
- Department of Ophthalmology, Toho University Sakura Medical Center, 564-1 Shimoshizu, Sakura 285-8741, Japan
| | - Ryuya Hashimoto
- Department of Ophthalmology, Toho University Sakura Medical Center, 564-1 Shimoshizu, Sakura 285-8741, Japan
| | - Hidetaka Masahara
- Department of Ophthalmology, Toho University Sakura Medical Center, 564-1 Shimoshizu, Sakura 285-8741, Japan
| | - Mizuho Oyamada
- Department of Ophthalmology, Toho University Sakura Medical Center, 564-1 Shimoshizu, Sakura 285-8741, Japan
| | - Takatoshi Maeno
- Department of Ophthalmology, Toho University Sakura Medical Center, 564-1 Shimoshizu, Sakura 285-8741, Japan
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Silverman RH, Urs R, Wapner RJ, Bearelly S. Plane-Wave Ultrasound Doppler of the Eye in Preeclampsia. Transl Vis Sci Technol 2020; 9:14. [PMID: 32974086 PMCID: PMC7490228 DOI: 10.1167/tvst.9.10.14] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 08/03/2020] [Indexed: 12/31/2022] Open
Abstract
Purpose Pre-eclampsia (PE) is a serious complication of pregnancy characterized by high blood pressure, proteinuria, compromised fetal blood supply, and potential organ damage. The superficial location of the eye makes it an ideal target for characterization hemodynamics. Our aim was to discern the impact of PE on ocular blood flow. Methods 18 MHz plane-wave ophthalmic ultrasound scanning was performed on subjects with PE (n = 26), chronic or gestational hypertension (n = 8), and normal controls (n = 19) within 72 hours of delivery. Duplicate three-second long scans of the posterior pole including the optic nerve were acquired at 6000 images/sec for evaluation of the central retinal artery and vein and the short posterior ciliary arteries. The choroid was scanned at 1000 images/sec. Doppler analysis provided values of pulsatile flow velocity and resistance indexes. Results End diastolic velocity was higher, and pulsatility and resistive indexes were significantly lower in the choroid, central retinal artery and short posterior ciliary arteries in PE than in controls. Blood pressure was elevated in PE with respect to controls and was negatively correlated with resistance. Conclusions Although vasoconstriction is considered characteristic of PE, we found reduced resistance in the orbital vessels and choroidal arterioles, implying vasodilation at this level. Future studies incorporating optical coherence tomography angiography for characterization of the retina and choriocapillaris in conjunction with plane-wave ultrasound scanning, particularly in late pregnancy, might address this conundrum. Translational Relevance Use of plane-wave ultrasound scanning for evaluation ocular blood flow in women at risk for PE may offer an avenue towards early detection and clinical intervention.
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Affiliation(s)
- Ronald H Silverman
- Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY, USA
| | - Raksha Urs
- Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY, USA
| | - Ronald J Wapner
- Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, New York, NY, USA
| | - Srilaxmi Bearelly
- Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY, USA
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14
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Abstract
Management of glaucoma during pregnancy represents a challenge for the physician. Important disease and patients' health decisions begin even before conception and continue throughout pregnancy and breastfeeding. The data on this topic is limited due to ethical and legal constraints and challenges of conducting large, prospective, and randomized clinical trials on this patient population. Our review suggests that individually, intraocular pressure is lower in a pregnant woman when compared with a nonpregnant woman. Importantly, the medical management of glaucoma during pregnancy poses special challenges due to the possibility of adverse effects of medications on the fetus and newborn. Laser trabeculoplasty and traditional filtration surgery, and minimally invasive glaucoma surgery, represent nondrug management options. Thus, managing glaucoma in pregnancy is a delicate balance between treatment to prevent damage to the optic nerve in the mother and avoidance of interventions potentially harmful to the fetus. This literature review of published individual and population-based studies was performed to explore current knowledge and guidelines in the management of glaucoma in pregnancy.
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15
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Kızıltunç PB, Varlı B, Büyüktepe TÇ, Atilla H. Ocular vascular changes during pregnancy: an optical coherence tomography angiography study. Graefes Arch Clin Exp Ophthalmol 2019; 258:395-401. [PMID: 31754828 DOI: 10.1007/s00417-019-04541-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 10/29/2019] [Accepted: 11/07/2019] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Pregnancy is a period presenting with many physiological adaptation mechanisms. One of the structures in which these mechanisms are observed is ocular tissues. The cornea, lacrimal and meibomian glands, and chorioretinal complex are all among the structures affected by changes during pregnancy. In this study we aimed to evaluate the macular and optic disc vessel density (VD) changes by Optical Coherence Tomography Angiography (OCTA) imaging in pregnancy. METHODS A total of 248 eyes from 124 pregnant women and 80 eyes from 40 healthy control women were involved. Vessel densities of macula were evaluated for superficial capillary plexus (SCP) and deep capillary plexus (DCP) in whole macula, foveal, parafoveal and perifoveal region. Peripapillary and whole optic disc VDs were also evaluated. Vessel densities of macula and optic disc were compared between control individuals and pregnant women. Vessel densities in different trimesters were also evaluated. RESULTS Modest but significant differences in VDs of whole macula of SCP and DCP were observed in pregnancy group. Additionally, perifoveal and parafoveal region of SCP, whole disc and radial peripapillary capillary VD were significantly higher in pregnancy group. There was no correlation between VD ratios of macula and optic disc and pregnancy weeks and trimesters. CONCLUSIONS This is the first study focusing on the OCTA parameters in pregnant individuals. These findings suggest that physiological changes during pregnancy are not limited to the cornea, eyelids and the choroid but also to the retinal and optic disc vasculature.
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Affiliation(s)
- Pınar Bingöl Kızıltunç
- Department of Ophthalmology, Ankara University School of Medicine, Vehbi Koç Eye Bank, Mamak, Ankara, Turkey.
| | - Bulut Varlı
- Department of Obstetrics and Gynecology, Ankara University School of Medicine, Ankara, Turkey
| | - Tuna Çelik Büyüktepe
- Department of Ophthalmology, Ankara University School of Medicine, Vehbi Koç Eye Bank, Mamak, Ankara, Turkey
| | - Huban Atilla
- Department of Ophthalmology, Ankara University School of Medicine, Vehbi Koç Eye Bank, Mamak, Ankara, Turkey
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16
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Kiyota N, Shiga Y, Ichinohasama K, Yasuda M, Aizawa N, Omodaka K, Honda N, Kunikata H, Nakazawa T. The Impact of Intraocular Pressure Elevation on Optic Nerve Head and Choroidal Blood Flow. Invest Ophthalmol Vis Sci 2019; 59:3488-3496. [PMID: 30025080 DOI: 10.1167/iovs.18-23872] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To use laser speckle flowgraphy (LSFG) to assess blood flow (BF) in the optic nerve head (ONH) tissue and choroid during elevated intraocular pressure (IOP). Methods This prospective study included 20 eyes of 20 healthy volunteers. The testing protocol had a baseline phase, two elevated IOP phases (+10 and +20 mm Hg), and a recovery phase. IOP was elevated by pushing against the eyelid with a novel tubular device attached to the LSFG apparatus. Measurement parameters in each phase included: LSFG-derived mean blur rate (MBR) and flow acceleration index (FAI); systemic parameters, and IOP. The % change against baseline was calculated for each phase. The protocol was repeated five times to calculate the coefficient of variation (CV) for % change MBR and to determine the effect of mydriasis on % change MBR. We compared % change MBR and FAI and evaluated the relationship between % change ocular perfusion pressure (OPP) and MBR in the choroid and ONH tissue. Results The % change MBR was highly reproducible (CV: 6.1-8.7%) and not affected by mydriasis (P = 0.57-0.96). The % change MBR and FAI were higher in the ONH tissue than choroid during IOP elevation (P = 0.04). The % change OPP and MBR showed positive linear correlations and two-segmental linear correlations in the choroid and ONH tissue, respectively (P < 0.01). Conclusion Hemodynamics during IOP elevation differ in the choroid and ONH tissue. LSFG enables highly reproducible assessment of the dynamic autoregulation of ocular BF in the ONH tissue.
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Affiliation(s)
- Naoki Kiyota
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Yukihiro Shiga
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan.,Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Kohei Ichinohasama
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Masayuki Yasuda
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Naoko Aizawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Kazuko Omodaka
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan.,Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Naoto Honda
- Development Sec. 9, Medical Development Department, Eye Care Division, NIDEK Co., Ltd, Aichi, Japan
| | - Hiroshi Kunikata
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan.,Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Toru Nakazawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan.,Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Miyagi, Japan.,Development Sec. 9, Medical Development Department, Eye Care Division, NIDEK Co., Ltd, Aichi, Japan.,Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Miyagi, Japan.,Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Miyagi, Japan
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17
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Evaluation of flicker induced hyperemia in the retina and optic nerve head measured by Laser Speckle Flowgraphy. PLoS One 2018; 13:e0207525. [PMID: 30485331 PMCID: PMC6261588 DOI: 10.1371/journal.pone.0207525] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 11/01/2018] [Indexed: 11/19/2022] Open
Abstract
Purpose The coupling between neural activity and blood flow is a physiological key principle of ocular blood flow regulation. The current study was performed to investigate whether Laser speckle flowgraphy (LSFG), a commercially available technique for measuring blood flow, is capable to assess flicker-induced haemodynamic changes in the retinal and optic nerve head (ONH) circulation. Methods Twenty healthy subjects were included in this cross sectional study. A commercial LSFG instrument was used to measure blood flow at the ONH as well as in retinal vessels before and during stimulation with flickering light. Mean blur rate (MBR), a measure of relative blood flow velocity, was obtained for the ONH and relative flow volume (RFV) a measure of relative blood flow of the respective retinal vessels. Results Stimulation with flicker light increased ONH MBR by +17.5%±6.6% (p<0.01). In retinal arteries, flicker stimulation led an increase of +23.8±10.0% (p<0.05) in total RFV. For retinal veins, an increase of +23.1%±11.0 (p<0.05) in total RFV was observed during stimulation. A higher response was observed in nasal RFV compared to temporal RFV in retinal arteries (nasal: +28.9%±20.0%; temporal: +20.4%±17.6%, p<0.05) and veins (nasal: +28.3%±19.6%; temporal +17.8%±18.9%, p<0.05). Conclusion As shown previously with other techniques, flicker stimulation leads to an increase in retinal and optic nerve head blood flow. Our results indicate that LSFG is an appropriate method for the quantification of retinal and ONH blood flow during visual stimulation and may be used as a non-invasive, easy to use tool to assess neuro-vascular coupling in humans.
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18
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Ismail A, Bhatti MS, Faye I, Lu CK, Laude A, Tang TB. Pulse waveform analysis on temporal changes in ocular blood flow due to caffeine intake: a comparative study between habitual and non-habitual groups. Graefes Arch Clin Exp Ophthalmol 2018; 256:1711-1721. [PMID: 29876732 DOI: 10.1007/s00417-018-4030-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 05/23/2018] [Accepted: 05/29/2018] [Indexed: 11/26/2022] Open
Abstract
PURPOSE To evaluate and compare the temporal changes in pulse waveform parameters of ocular blood flow (OBF) between non-habitual and habitual groups due to caffeine intake. METHOD This study was conducted on 19 healthy subjects (non-habitual 8; habitual 11), non-smoking and between 21 and 30 years of age. Using laser speckle flowgraphy (LSFG), three areas of optical nerve head were analyzed which are vessel, tissue, and overall, each with ten pulse waveform parameters, namely mean blur rate (MBR), fluctuation, skew, blowout score (BOS), blowout time (BOT), rising rate, falling rate, flow acceleration index (FAI), acceleration time index (ATI), and resistive index (RI). Two-way mixed ANOVA was used to determine the difference between every two groups where p < 0.05 is considered significant. RESULT There were significant differences between the two groups in several ocular pulse waveform parameters, namely MBR (overall, vessel, tissue), BOT (overall), rising rate (overall), and falling rate (vessel), all with p < 0.05. In addition, the ocular pulse waveform parameters, i.e., MBR (overall), skew (tissue), and BOT (tissue) showed significant temporal changes within the non-habitual group, but not within the habitual group. The temporal changes in parameters MBR (vessel, tissue), skew (overall, vessel), BOT (overall, vessel), rising rate (overall), falling rate (overall, vessel), and FAI (tissue) were significant for both groups (habitual and non-habitual) in response to caffeine intake. CONCLUSION The experiment results demonstrated caffeine does modulate OBF significantly and response differently in non-habitual and habitual groups. Among all ten parameters, MBR and BOT were identified as the suitable biomarkers to differentiate between the two groups.
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Affiliation(s)
- Aishah Ismail
- Centre for Intelligent Signal and Imaging Research (CISIR), Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia
| | - Mehwish S Bhatti
- Centre for Intelligent Signal and Imaging Research (CISIR), Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia
| | - Ibrahima Faye
- Centre for Intelligent Signal and Imaging Research (CISIR), Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia
| | - Cheng Kai Lu
- Centre for Intelligent Signal and Imaging Research (CISIR), Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia
| | - Augustinus Laude
- Centre for Intelligent Signal and Imaging Research (CISIR), Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia
- Tan Tock Seng Hospital, National Healthcare Group Eye Institute, Jalan Tan Tock Seng, Singapore, Singapore
- Lee Kong Chian School of Medicine and School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Tong Boon Tang
- Centre for Intelligent Signal and Imaging Research (CISIR), Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia.
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