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Stodtmeister R, Menzel A, Klimova A, Herber R, Pillunat KR, Pillunat LE. Measurement of the retinal venous pressure with a new instrument in patients with primary open angle glaucoma. Graefes Arch Clin Exp Ophthalmol 2024; 262:1633-1639. [PMID: 38214734 PMCID: PMC11031493 DOI: 10.1007/s00417-023-06326-4] [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: 02/04/2022] [Revised: 08/28/2023] [Accepted: 11/20/2023] [Indexed: 01/13/2024] Open
Abstract
PURPOSE To compare the results of retinal venous pressure (RVP) measurement performed with contact lens dynamometry (CLD) and with the new IOPstim. METHODS In this cross-sectional study, we included 36 patients with primary open angle glaucoma with a median age (Q25; Q75) of 74 (64; 77) years (m/f = 18/18), baseline intraocular pressure (IOP): 13.9 (12.2; 15.1) mmHg. Median mean defect: - 5.8 (- 11.9; - 2.6) db. Principle of the IOPstim: an empty balloon with a diameter of 8 mm is positioned on the eye, laterally of the limbus. Under observation of the central retinal vein (CRV), the examiner inflates the balloon. As soon as the CRV starts pulsation, the inflation is stopped and the IOP is measured, equaling the RVP at this moment. In the CLD, the pulsation of the CRV is observed with a contact lens. The RVP is calculated from the attachment force applied when pulsation appears. COURSE OF EXAMINATIONS Three single measurements of RVP in quick succession with both methods. The sequence of the two methods was randomized. The means of the three RVP measurements were compared. RESULTS Pressures in mmHg. RVP: IOPstim: 19.4 ± 5.4 (mean ± SD), CLD: 20.3 ± 5.9. Range of three single measurements: IOPstim: 2.9 ± 1.5, CLD: 2.2 ± 1.1. The differences were RVPIOPstim - RVPCLD = - 0.94 ± 1.15, and approximately normally distributed. Bland-Altman analysis: only one data point was 0.5 mmHg higher than the upper line of agreement. The confidence interval of this line was 0.65 mmHg. Concordance correlation coefficient according to Lin (CCC): 0.96. Intraclass correlation coefficient: both methods, 0.94. CONCLUSION In both methods, the range of the single measurements may be taken as a sign of good reliability, the CCC of 0.96 as a sign of a very good agreement. At the mean, the IOPstim RVP values were 1 mmHg lower than those obtained with the CLD. This difference may be due to the different directions of the prevailing force vectors induced by the instruments. The IOPstim seems applicable in glaucoma diagnostics.
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Affiliation(s)
- Richard Stodtmeister
- Department of Ophthalmology, Univ. Hospital Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Aline Menzel
- Department of Ophthalmology, Univ. Hospital Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Anna Klimova
- National Center for Tumor Diseases (NCT/UCC), German Cancer Research Center (DKFZ), Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01307, Dresden, Germany
| | - Robert Herber
- Department of Ophthalmology, Univ. Hospital Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Karin R Pillunat
- Department of Ophthalmology, Univ. Hospital Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307, Dresden, Germany.
| | - Lutz E Pillunat
- Department of Ophthalmology, Univ. Hospital Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
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Khoo YJ, Yu DY, Abdul-Rahman A, Balaratnasingam C, Chen FK, McAllister IL, Morgan WH. Vessel Pulse Amplitude Mapping in Eyes With Central and Hemi Retinal Venous Occlusion. Transl Vis Sci Technol 2023; 12:26. [PMID: 36692455 PMCID: PMC9896842 DOI: 10.1167/tvst.12.1.26] [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] [Indexed: 01/25/2023] Open
Abstract
Purpose The purpose of this study was to describe vessel pulse amplitude characteristics in eyes with central retinal vein occlusion (CRVO), hemiretinal vein occlusion (HVO), normal eyes (N1 N1), and the unaffected contralateral eyes of CRVO and HVO eyes (N1 CRVO and N1 HVO), as well as the unaffected hemivessels of HVO eyes (N2 HVO). Methods Ophthalmodynamometry estimates of blood column pulse amplitudes with modified photoplethysmography were timed against cardiac cycles. Harmonic analysis was performed on the vessel reflectance within 0.25 to 1 mm from the disc center to construct pulse amplitude maps. Linear mixed modeling was used to examine variable effects upon the log harmonic pulse amplitude. Results One hundred seven eyes were examined. Normal eyes had the highest mean venous pulse amplitude (2.08 ± 0.48 log u). CRVO had the lowest (0.99 ± 0.45 log u, P < 0.0001), followed by HVO (1.23 ± 0.46 log u, P = 0.0002) and N2 HVO (1.30 ± 0.59 log u, P = 0.0005). N1 CRVO (1.76 ± 0.34 log u, P = 0.52) and N1 HVO (1.33 ± 0.37 log u, P = 0.0101) had no significantly different mean amplitudes compared to N1 N1. Arterial amplitudes were lower than venous (P < 0.01) and reduced with venous occlusion (P < 0.01). Pulse amplitude versus amplitude over distance decreased along the N1 N1 vessels, with increasing slopes observed with CRVO (P < 0.01). Conclusions Pulse amplitude reduction and attenuation characteristics of arteries and veins in venous occlusion can be measured and are consistent with reduced vessel wall compliance and pulse wave transmission. Translational Relevance Retinal vascular pulse amplitudes can be measured, revealing occlusion induced changes, suggesting a role in evaluating the severity and progression of venous occlusion.
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Affiliation(s)
- Ying J. Khoo
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Western Australia, Australia,Lions Eye Institute, Nedlands, Western Australia, Australia
| | - Dao-Yi Yu
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Western Australia, Australia,Lions Eye Institute, Nedlands, Western Australia, Australia
| | - Anmar Abdul-Rahman
- Lions Eye Institute, Nedlands, Western Australia, Australia,Department of Ophthalmology, Counties Manukau District Health Board, Auckland, New Zealand
| | - Chandra Balaratnasingam
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Western Australia, Australia,Lions Eye Institute, Nedlands, Western Australia, Australia
| | - Fred K. Chen
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Western Australia, Australia,Lions Eye Institute, Nedlands, Western Australia, Australia,Ophthalmology Department, Royal Perth Hospital, Perth, Western Australia, Australia,Ophthalmology, Department of Surgery, The University of Melbourne, East Melbourne, Victoria, Australia,Centre for Eye Research Australia, The Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia
| | - Ian L. McAllister
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Western Australia, Australia,Lions Eye Institute, Nedlands, Western Australia, Australia
| | - William H. Morgan
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Western Australia, Australia,Lions Eye Institute, Nedlands, Western Australia, Australia,Ophthalmology Department, Royal Perth Hospital, Perth, Western Australia, Australia
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Hua Y, Lu Y, Walker J, Lee PY, Tian Q, McDonald H, Pallares P, Ji F, Brazile BL, Yang B, Voorhees AP, Sigal IA. Eye-specific 3D modeling of factors influencing oxygen concentration in the lamina cribrosa. Exp Eye Res 2022; 220:109105. [PMID: 35568202 PMCID: PMC11007759 DOI: 10.1016/j.exer.2022.109105] [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: 12/21/2021] [Revised: 04/06/2022] [Accepted: 04/28/2022] [Indexed: 11/29/2022]
Abstract
Our goal was to identify the factors with the strongest influence on the minimum lamina cribrosa (LC) oxygen concentration as potentially indicative of conditions increasing hypoxia risk. Because direct measurement of LC hemodynamics and oxygenation is not yet possible, we developed 3D eye-specific LC vasculature models. The vasculature of a normal monkey eye was perfusion-labeled post-mortem. Serial cryosections through the optic nerve head were imaged using fluorescence and polarized light microscopy to visualize the vasculature and collagen, respectively. The vasculature within a 450 μm-thick region containing the LC - identified from the collagen, was segmented, skeletonized, and meshed for simulations. Using Monte Carlo sampling, 200 vascular network models were generated with varying vessel diameter, neural tissue oxygen consumption rate, inflow hematocrit, and blood pressures (arteriole, venule, anterior boundary, and posterior boundary). Factors were varied over ranges of baseline ±20% with uniform probability. For each model we first obtained the blood flow, and from this the neural tissue oxygen concentration. ANOVA was used to identify the factors with the strongest influence on the minimum (10th percentile) oxygen concentration in the LC. The three most influential factors were, in ranked order, vessel diameter, neural tissue oxygen consumption rate, and arteriole pressure. There was a strong interaction between vessel diameter and arteriole pressure whereby the impact of one factor was larger when the other factor was small. Our results show that, for the eye analyzed, conditions that reduce vessel diameter, such as vessel compression due to elevated intraocular pressure or gaze-induced tissue deformation, may particularly contribute to decreased LC oxygen concentration. More eyes must be analyzed before generalizing.
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Affiliation(s)
- Yi Hua
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Yuankai Lu
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Jason Walker
- Department of Biological Science, University of Pittsburgh, Pittsburgh, PA, United States
| | - Po-Yi Lee
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States
| | - Qi Tian
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States
| | - Haiden McDonald
- Department of Biological Science, University of Pittsburgh, Pittsburgh, PA, United States
| | - Pedro Pallares
- Department of Biological Science, University of Pittsburgh, Pittsburgh, PA, United States
| | - Fengting Ji
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States
| | - Bryn L Brazile
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Bin Yang
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States; Department of Engineering, Rangos School of Health Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Andrew P Voorhees
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Ian A Sigal
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States.
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Nowrouzi A, Kafiabasabadi S, Rodriguez-Calzadilla M, Benitez-Del-Castillo J, Soto-Guerrero A, Diaz-Ramos A, Marques-Cavalcante KV. Central retinal vein occlusion in a patient using the antipsychotic drug olanzapine: a case report. J Med Case Rep 2021; 15:307. [PMID: 34049568 PMCID: PMC8164284 DOI: 10.1186/s13256-021-02865-8] [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: 04/09/2020] [Accepted: 04/15/2021] [Indexed: 11/28/2022] Open
Abstract
Background We report our findings in a patient who developed central retinal vein occlusion (CRVO) and was a chronic user of olanzapine, an antipsychotic medication. Case presentation A 50-year-old Caucasian man, non-smoker, was referred to our clinic with the chief complaint of floater appearance in his left eye for the past 3 days. His past medical history indicated that he had been taking antipsychotic drugs (olanzapine) for about 3 years, with no other systemic disease or risk factors for CRVO. In the examination, his best-corrected visual acuity (BCVA) was 0.7 in the left eye. The fundus showed signs of nonischemic CRVO with subhyaloid hemorrhage and intraretinal hemorrhage in the posterior pole and superior and inferior retina, without macular edema, confirmed by optical coherence tomography (OCT). We ruled out other probable differential diagnoses and risk factors which lead to CRVO through a complete physical exam and blood analysis (complete blood count, glucose, urea, creatinine, lipid profile, erythrocyte sedimentation rate, C-reactive protein, prothrombin time, partial thromboplastin time, Bleeding time (BT), fibrinogen level, proteins, antiphospholipid antibodies, homocysteine blood level, antithrombin III, protein C and S, factor V Leiden, prothrombin mutation, angiotensin-converting enzyme level, other autoantibodies, and human leukocyte antigen [HLA]-B51). Finally, we confirmed the probable side effect of olanzapine in CRVO, which has not been previously reported. A possible pro-thrombogenic mechanism of olanzapine at the molecular level is an affinity for 5-HT2Aserotonin receptors. Blocking these receptors results in increased platelet aggregation and increased blood coagulability. Conclusions These results indicate that CRVO can be a complication of chronic use of antipsychotic medications such as olanzapine, as shown for the first time in our case report. Clinicians should question patients who develop a sudden CRVO whether they are using antipsychotic medications such as olanzapine.
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Affiliation(s)
- Ali Nowrouzi
- Ophthalmology Department of Hospital universitario SAS Jerez de la Frontera, Jerez de la Frontera, Spain.
| | | | - Mario Rodriguez-Calzadilla
- Ophthalmology Department of Hospital universitario SAS Jerez de la Frontera, Jerez de la Frontera, Spain
| | | | - Alejandro Soto-Guerrero
- Ophthalmology Department of Hospital universitario SAS Jerez de la Frontera, Jerez de la Frontera, Spain
| | - Antonio Diaz-Ramos
- Ophthalmology Department of Hospital universitario SAS Jerez de la Frontera, Jerez de la Frontera, Spain
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Kida T, Flammer J, Konieczka K, Ikeda T. Retinal venous pressure is decreased after anti-VEGF therapy in patients with retinal vein occlusion-related macular edema. Graefes Arch Clin Exp Ophthalmol 2021; 259:1853-1858. [PMID: 33447857 PMCID: PMC8277612 DOI: 10.1007/s00417-020-05068-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/07/2020] [Accepted: 12/28/2020] [Indexed: 11/29/2022] Open
Abstract
Purpose The pathomechanism leading to retinal vein occlusion (RVO) is unclear. Mechanical compression, thrombosis, and functional contractions of veins are discussed as the reasons for the increased resistance of venous outflow. We evaluated changes in the retinal venous pressure (RVP) following intravitreal injection of anti-vascular endothelial growth factor (VEGF) agent to determine the effect on RVO-related macular edema. Methods Twenty-six patients with RVO-related macular edema (16 branch RVOs [BRVOs] and 10 central RVOs [CRVOs], age 72.5 ± 8.8 years) who visited our hospital were included in this prospective study. Visual acuity (VA), intraocular pressure (IOP), central retinal thickness (CRT) determined by macular optical coherence tomography, and RVP measured using an ophthalmodynamometer were obtained before intravitreal injection of ranibizumab (IVR) and 1 month later. Results Comparison of the BRVOs and CRVOs showed that VA was significantly improved by a single injection in BRVOs (P < 0.0001; P = 0.1087 for CRVOs), but CRT and RVP were significantly decreased without significant difference in IOP after the treatment in both groups (P < 0.0001). Conclusion The anti-VEGF treatment resulted in a significant decrease in the RVP, but the RVP remained significantly higher than the IOP. An increased RVP plays a decisive role in the formation of macula edema, and reducing it is desirable.
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Affiliation(s)
- Teruyo Kida
- Department of Ophthalmology, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka, 569-8686, Japan.
| | - Josef Flammer
- Department of Ophthalmology, University of Basel, Basel, Switzerland
| | | | - Tsunehiko Ikeda
- Department of Ophthalmology, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka, 569-8686, Japan
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Stodtmeister R, Koch W, Georgii S, Pillunat KR, Spörl E, Pillunat LE. The Distribution of Retinal Venous Pressure and Intraocular Pressure Differs Significantly in Patients with Primary Open-Angle Glaucoma. Klin Monbl Augenheilkd 2021; 239:319-325. [PMID: 33434930 DOI: 10.1055/a-1318-9991] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
INTRODUCTION Until now, venous pressure within the eye has widely been equated with intraocular pressure (IOP). Measurements with dynamometers calibrated in instrument units or in force showed that the retinal venous pressure (RVP) may be higher than the IOP in glaucoma patients. In this study, the RVP was measured with a contact lens dynamometer calibrated in mmHg. METHODS Study type: cross-sectional. SUBJECTS Fifty consecutive patients with primary open-angle glaucoma (POAG) who underwent diurnal curve measurement under medication. Age: 69 ± 8 years. Measurement of RVP: contact lens dynamometry. IOP measurement: dynamic contour tonometry. RESULTS Pressures are given in mmHg. In all 50 patients, the IOP was 15.9 (13.6; 17.1) [median (Q1; Q3)], and the RVP was 17.4 (14.8; 27.2). The distribution of the IOP was normal and that of the RVP was right skewed. In the subgroup of 34 patients with spontaneous pulsation of the central retinal vein (SVP), the IOP and therefore, by definition, the RVP was 16.5 (13.7; 17.4). In the subgroup of 16 patients without SVP, the IOP was 14.8 (13.3; 16.4), and the RVP was 31.3 (26.2; 38.8) (p ≤ 0.001). In systemic treatment, the prescribed drugs were (the number of patients is given in parentheses): ACE inhibitors (20), β-blockers (17), angiotensin II-receptor blockers (13), calcium channel blockers (12), diuretics (7). No difference in RVP was observed between patients receiving these drugs and not receiving them, except in the β-blocker group. Here, the 17 patients with systemic β-blockers had a median RVP of 15.6 mmHg and without 20.2 mmHg (p = 0.003). In the 16 patients with a higher RVP than IOP, only one patient received a systemic β-blocker. The median IOP was 15.7 mmHg with systemic β-blockers and 16.1 mmHg without (p = 0.85). CONCLUSION In a subgroup of 16 of the 50 patients studied, the RVP was greater than the IOP by a highly statistically and clinically significant degree. According to the widely accepted thinking on the pathophysiology of retinal and optic nerve head circulation, the blood flow in these tissues may be much more compromised in this group of patients than has been assumed. They may be identified by a missing SVP. Topical and systemic medications showed no statistically significant influence on the RVP, except for the systemic β-blockers, in which the RVP was lower by 4.6 mmHg than for the patients who did not receive these drugs (p = 0.003).
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Affiliation(s)
- Richard Stodtmeister
- Augenklinik, Technische Universität Dresden, Dresden, Germany.,Augenarzt, Augenspezialisten Saar, Völklingen, Germany
| | - Wiebke Koch
- Augenklinik, Technische Universität Dresden, Dresden, Germany
| | - Sylvana Georgii
- Augenklinik, Technische Universität Dresden, Dresden, Germany
| | | | - Eberhard Spörl
- Augenklinik, Technische Universität Dresden, Dresden, Germany
| | - Lutz E Pillunat
- Augenklinik, Technische Universität Dresden, Dresden, Germany
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Chuangsuwanich T, Hung PT, Wang X, Liang LH, Schmetterer L, Boote C, Girard MJA. Morphometric, Hemodynamic, and Biomechanical Factors Influencing Blood Flow and Oxygen Concentration in the Human Lamina Cribrosa. Invest Ophthalmol Vis Sci 2020; 61:3. [PMID: 32271886 PMCID: PMC7401712 DOI: 10.1167/iovs.61.4.3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Purpose We developed a combined biomechanical and hemodynamic model of the human eye to estimate blood flow and oxygen concentration within the lamina cribrosa (LC) and rank the factors that influence LC oxygen concentration. Methods We generated 5000 finite-element eye models with detailed microcapillary networks of the LC and computed the oxygen concentration of the lamina retinal ganglion cell axons. For each model, we varied the intraocular pressure (IOP) from 10 mm Hg to 55 mm Hg in 5-mm Hg increments, the cerebrospinal fluid pressure (13 ± 2 mm Hg), cup depth (0.2 ± 0.1 mm), scleral stiffness (±20% of the mean values), LC stiffness (0.41 ± 0.2 MPa), LC radius (1.2 ± 0.12 mm), average LC pore size (5400 ± 2400 µm2), the microcapillary arrangement (radial, isotropic, or circumferential), and perfusion pressure (50 ± 9 mm Hg). Blood flow was assumed to originate from the LC periphery and drain via the central retinal vein. Finally, we performed linear regressions to rank the influence of each factor on the LC tissue oxygen concentration. Results LC radius and perfusion pressure were the most important factors in influencing the oxygen concentration of the LC. IOP was another important parameter, and eyes with higher IOP had higher compressive strain and slightly lower oxygen concentration. In general, superior–inferior regions of the LC had significantly lower oxygen concentration than the nasal–temporal regions, resulting in an hourglass pattern of oxygen deficiency. Conclusions To the best of our knowledge, this study is the first to implement a comprehensive hemodynamical model of the eye that accounts for the biomechanical forces and morphological parameters of the LC. The results provide further insight into the possible relationship of biomechanical and vascular pathways leading to ischemia-induced optic neuropathy.
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Shin YI, Nam KY, Lee SE, Lim HB, Lee MW, Jo YJ, Kim JY. Changes in Peripapillary Microvasculature and Retinal Thickness in the Fellow Eyes of Patients With Unilateral Retinal Vein Occlusion: An OCTA Study. Invest Ophthalmol Vis Sci 2019; 60:823-829. [PMID: 30807638 DOI: 10.1167/iovs.18-26288] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To evaluate changes in peripapillary microvascular parameters in the fellow eyes of patients with unilateral retinal vein occlusion (RVO) using optical coherence tomography angiography (OCTA) and to determine the relationships between peripapillary microvasculature and retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GC-IPL) thickness. Methods Eighty-three patients with unilateral RVO (50 patients with branch RVO and 33 with central RVO) and 83 normal controls were enrolled. OCTA (Cirrus HD-OCT 5000 with AngioPlex) 6 × 6-mm scans centered on the optic disc were acquired. Peripapillary vessel density (VD) and perfusion density (PD) were automatically calculated. Results The average RNFL and GC-IPL thicknesses in the fellow eyes of RVO patients were significantly thinner than in normal controls (93.5 vs. 96.6 μm, P = 0.013 and 81.3 vs. 84.1 μm, P = 0.003, respectively). In the fellow eyes of patients with unilateral RVO, the peripapillary VD of the inner ring, outer ring, and full area (17.47, 18.50, and 17.89, respectively) were significantly lower than those of controls (17.87, 18.87, and 18.27, respectively). The peripapillary PD of the inner ring, outer ring, and full area (0.456, 0.467, and 0.456, respectively) were also significantly lower than those of controls (0.468, 0.476, and 0.466, respectively). RNFL and GC-IPL thicknesses were correlated with both peripapillary VD and PD. Conclusions OCTA revealed that peripapillary microvascular parameters in the fellow eyes of patients with unilateral RVO were decreased, and GC-IPL and RNFL thinning were also observed. The RNFL and GC-IPL thicknesses were positively correlated with both peripapillary VD and PD.
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Affiliation(s)
- Yong-Il Shin
- Department of Ophthalmology, Chungnam National University College of Medicine, Daejeon, Republic of Korea
| | - Ki Yup Nam
- Department of Ophthalmology, Kosin University College of Medicine, Busan, Republic of Korea
| | - Seong Eun Lee
- Department of Ophthalmology, Chungnam National University College of Medicine, Daejeon, Republic of Korea
| | - Hyung-Bin Lim
- Department of Ophthalmology, Chungnam National University College of Medicine, Daejeon, Republic of Korea
| | - Min Woo Lee
- Department of Ophthalmology, Chungnam National University College of Medicine, Daejeon, Republic of Korea
| | - Young-Joon Jo
- Department of Ophthalmology, Chungnam National University College of Medicine, Daejeon, Republic of Korea
| | - Jung-Yeul Kim
- Department of Ophthalmology, Chungnam National University College of Medicine, Daejeon, Republic of Korea
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Mustur D, Vahedian Z, Bovet J, Mozaffarieh M. Retinal venous pressure measurements in patients with Flammer syndrome and metabolic syndrome. EPMA J 2017; 8:339-344. [PMID: 29209437 DOI: 10.1007/s13167-017-0105-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 06/20/2017] [Indexed: 10/18/2022]
Abstract
Background The purpose of this research is to analyze retinal venous pressure (RVP) of both eyes of patients who visited a Swiss ophthalmic practice and compare values among the following groups of patients with primary open-angle glaucoma (POAG), Flammer syndrome (FS), and metabolic syndrome (MetS). Methods RVP was measured in both eyes of all patients who visited a Swiss ophthalmic practice during March 2016 till November 2016, and the results were analyzed retrospectively. All measurements were performed by one physician by means of ophthalmodynamometry. Ophthalmodynamometry is done by applying an increasing pressure on the eye via a contact lens. The minimum force required to induce a venous pulsation is called ophthalmodynamometric force (ODF). The RVP is defined and calculated as the sum of ODF and intraocular pressure (IOP) [RVP = ODF + IOP]. Results Spontaneous central retinal venous pulsation was present in the majority of the patients (192 out of 357, 53.8%). Spontaneous RVP rate was significantly negatively correlated with age (r = -0.348, p < 0.001). A significantly increased RVP was noted in FS, MetS, and POAG patients, particularly those POAG patients who also suffered from FS (p < 0.005). Conclusions Although most patients had a spontaneous RVP, those with FS, POAG, and MetS had increased RVP. Measuring RVP by means of ophthalmodynamometry provides predictive information about certain ocular diseases and aids in instituting adequate preventive measures.
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Affiliation(s)
- Dominique Mustur
- Department of Ophthalmology, University of Basel, Mittlere Str 91, 4031 Basel, Switzerland.,Augenglatt Center, Zürich, Switzerland
| | - Zakieh Vahedian
- Glaucoma Service, Farabi Eye Hospital, Tehran University of Medical Sciences, Teheran, Iran
| | | | - Maneli Mozaffarieh
- Department of Ophthalmology, University of Basel, Mittlere Str 91, 4031 Basel, Switzerland.,Augenglatt Center, Zürich, Switzerland
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Konieczka K, Erb C. Diseases potentially related to Flammer syndrome. EPMA J 2017; 8:327-332. [PMID: 29209435 PMCID: PMC5700007 DOI: 10.1007/s13167-017-0116-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 08/22/2017] [Indexed: 02/03/2023]
Abstract
Flammer syndrome (FS) is a prevalent and mostly benign condition. Subjects with FS seem to have a good life expectancy. Nevertheless, FS subjects are at increased risk for certain diseases, mainly when they are challenged by psychological stress or other stimuli such as coldness. FS is related to ocular diseases, such as normal-tension glaucoma, retinitis pigmentosa, central serous chorioretinopathy, optic nerve compartment syndrome, Leber’s hereditary optic neuropathy, arterial or venous occlusions in the retina, and choroid and optic nerve head, despite the absence of classical vascular risk factors. FS is also related to some non-ocular diseases, such as multiple sclerosis, breast cancer, and altitude sickness. The role of FS in other diseases such as tinnitus, sudden hearing loss, Ménière’s disease, anorexia nervosa, and thyroid dysfunction is currently under investigation. The exact relationship of FS to related diseases however still needs to be established. This may hopefully lead to more targeted diagnostics and personalized treatments.
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Affiliation(s)
- Katarzyna Konieczka
- Department of Ophthalmology, University of Basel, Mittlere Strasse 91, CH-4031 Basel, Switzerland
| | - Carl Erb
- Eye Clinic Wittenbergplatz, Berlin, Germany
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Konieczka K, Fraenkl S, Mozaffarieh M, Flammer J. Glaucoma Progression in the Unaffected Fellow Eye of Glaucoma Patients who Developed Unilateral Branch Retinal Vein Occlusion. Am J Ophthalmol 2017; 181:175. [PMID: 28712491 DOI: 10.1016/j.ajo.2017.05.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 04/27/2017] [Accepted: 05/01/2017] [Indexed: 10/19/2022]
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Taki K, Kida T, Fukumoto M, Sato T, Oku H, Ikeda T. Central Retinal Vein Occlusion in 2 Patients Using Antipsychotic Drugs. Case Rep Ophthalmol 2017; 8:410-415. [PMID: 28924438 PMCID: PMC5597922 DOI: 10.1159/000479219] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 07/04/2017] [Indexed: 01/28/2023] Open
Abstract
Purpose To report our findings in 2 patients who developed a central retinal vein occlusion (CRVO) and were chronic users of antipsychotic medications. Case Presentation Case 1 was a 62-year-old woman who had a sudden reduction of vision in her right eye to 20/2,000. Her fundus showed signs of an impending CRVO with marked macular edema. She had been taking antipsychotic drugs (quetiapine fumarate and risperidone) for about 2 years. She refused anti-VEGF therapy for her macular edema but selected systemic kallidinogenase. Two days later, the macular edema was significantly reduced but the number of cotton wool spots (CWS) was increased. Ten days later, the macular edema was resolved and her BCVA improved to 20/60. The CWS gradually disappeared, and her BCVA improved to 20/20. Case 2 was a 43-year-old man who presented with vision reduction in his right eye of 1 week's duration. His BCVA was 20/50 and his fundus showed signs of a CRVO-related macular edema with CWS in the peripapillary area. He had been taking sulpiride (Dogmatyl™) for depression for 1 year, and his blood test showed an increase in red blood cells and hematocrit. Anti-VEGF therapy was performed, and the macular edema was resolved with vision improving to 20/20. There has been no recurrence to date in both cases. Conclusions These results indicate that a CRVO can be a complication of chronic use of antipsychotic medications. However, early treatment can lead to good outcomes. Clinicians should question patients who develop a sudden CRVO whether they are using antipsychotic medications.
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Affiliation(s)
- Koichiro Taki
- Department of Ophthalmology, Osaka Medical College, Takatsuki, Japan
| | - Teruyo Kida
- Department of Ophthalmology, Osaka Medical College, Takatsuki, Japan
| | - Masanori Fukumoto
- Department of Ophthalmology, Osaka Medical College, Takatsuki, Japan
| | - Takaki Sato
- Department of Ophthalmology, Osaka Medical College, Takatsuki, Japan
| | - Hidehiro Oku
- Department of Ophthalmology, Osaka Medical College, Takatsuki, Japan
| | - Tsunehiko Ikeda
- Department of Ophthalmology, Osaka Medical College, Takatsuki, Japan
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Blechschmidt T, Krumsiek M, Todorova MG. Acupuncture benefits for Flammer syndrome in individuals with inherited diseases of the retina. EPMA J 2017; 8:177-185. [PMID: 28725294 PMCID: PMC5486528 DOI: 10.1007/s13167-017-0096-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 05/15/2017] [Indexed: 11/28/2022]
Abstract
BACKGROUND Patients with inherited diseases of the retina (IRD) often exhibit signs and symptoms of Flammer syndrome (FS). Acupuncture treatment has shown its positive effect on visual function in patients with IRD. The aim of the present study is to examine the effect of acupuncture on signs and symptoms of FS in a cohort of patients suffering simultaneously FS and IRD. PATIENTS AND METHODS A prospective pilot study was performed on 17 patients with FS and IRD: rod-cone dystrophy, Nr: 12 (RCD); cone-rod dystrophy, Nr: 3 (CRD) and inherited macular dystrophy, Nr: 2 (IMD; 12♀, 5♂; mean age: 44.19 y; SD ±17.09 y). Acupuncture treatment was done applying needle acupuncture of the body and the ears. The treatment was scheduled at 10 half-hour sessions over 5 weeks. Primary outcome was evaluation of the post-acupuncture effect on the signs and symptoms of FS in IRD patients using multiple-choice questionnaires. RESULTS Following acupuncture, we found improvement in signs and symptoms of FS in patients suffering simultaneously IRD, as for instance (Nr. patients: improvement/suffering/total): a reduced tiredness (10/11/17), shorter sleep onset time (10/11/17), warmer feet and hands (10/10/17) and reduced frequency of headache attacks (9/11/17). Surprisingly, in four RCD patients and in one IMD patient, a reduction of macular edema was documented. CONCLUSIONS The applied acupuncture protocol for FS in IRD patients showed improvement in FS signs and symptoms and was tolerated well. Nevertheless, the objective evaluation of this complementary therapy on FS in IRD patients remains to be elucidated.
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Affiliation(s)
- Tilo Blechschmidt
- Department of Ophthalmology, University of Basel, Mittlere Strasse 91, CH-4031 Basel, Switzerland
| | - Maike Krumsiek
- Department of Ophthalmology, University of Basel, Mittlere Strasse 91, CH-4031 Basel, Switzerland
| | - Margarita G Todorova
- Department of Ophthalmology, University of Basel, Mittlere Strasse 91, CH-4031 Basel, Switzerland
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Flammer J, Konieczka K. The discovery of the Flammer syndrome: a historical and personal perspective. EPMA J 2017; 8:75-97. [PMID: 28725290 PMCID: PMC5486542 DOI: 10.1007/s13167-017-0090-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 03/27/2017] [Indexed: 12/21/2022]
Abstract
This review describes the clinical and basic research that led to the description of Flammer syndrome. It is narrated from a personal perspective. This research was initiated by the observation of an increased long-term fluctuation of visual fields in a subgroup of glaucoma patients. As these patients had strikingly cold hands, peripheral blood flow was tested with a capillary microscopy, and vasospastic syndrome (VS) was diagnosed. Further studies on these patients revealed frequently weakened autoregulation of ocular blood flow and increased flow resistivity in retroocular vessels. Their retinal vessels were more rigid and irregular and responded less to flickering light. Holistic investigation demonstrated low blood pressure, silent myocardial ischaemia, altered beat-to-beat variation, altered gene expression in the lymphocytes, slightly increased plasma endothelin level and increased systemic oxidative stress. This combination of signs and symptoms was better described by the term primary vascular dysregulation (PVD) than by VS. Subsequent studies showed additional symptoms frequently related to PVD, such as low body mass index, cold extremities combined with slightly increased core temperature, prolonged sleep onset time, reduced feelings of thirst, increased sensitivity to smell and also for certain drugs and increased retinal venous pressure. To better characterise this entire syndrome, the term Flammer syndrome (FS) was introduced. Most subjects with FS were healthy. Nevertheless, FS seemed to increase the risk for certain eye diseases, particularly in younger patients. This included normal-tension glaucoma, anterior ischaemic optic neuropathy, retinal vein occlusions, Susac syndrome and central serous chorioretinopathy. Hereditary diseases, such as Leber’s optic neuropathy or retinitis pigmentosa, were also associated with FS, and FS symptoms and sings occurred more frequent in patients with multiple sclerosis or with acute hearing loss. Further research should lead to a more concise definition of FS, a precise diagnosis and tools for recognizing people at risk for associated diseases. This may ultimately lead to more efficient and more personalised treatment.
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Affiliation(s)
- Josef Flammer
- Department of Ophthalmology, University of Basel, Mittlere Strasse 91, CH-4031 Basel, Switzerland
| | - Katarzyna Konieczka
- Department of Ophthalmology, University of Basel, Mittlere Strasse 91, CH-4031 Basel, Switzerland
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Baertschi M, Dayhaw-Barker P, Flammer J. The effect of hypoxia on intra-ocular, mean arterial, retinal venous and ocular perfusion pressures. Clin Hemorheol Microcirc 2017; 63:293-303. [PMID: 26639768 DOI: 10.3233/ch-152025] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
INTRODUCTION High altitude hypoxia is linked to decreased blood oxygen saturation with a related increase of Endothelin-1 (ET-1) blood plasma levels. As a consequence of such elevated ET-1 levels, alterations of retinal venous and ocular perfusion pressures are suspected. PURPOSE To measure the effect of hypoxia on intra-ocular pressure, mean arterial pressure, retinal venous pressure and to calculate ocular perfusion pressure. METHOD An experimental, prospective cohort study with 33 healthy subjects was conducted in which the subjects were confronted with long-term (days) environmental hypoxia at high altitudes. Mean arterial pressure, arterial blood oxygen saturation, intra-ocular pressure, retinal venous and ocular perfusion pressure were measured at 300 m/1'000 ft (baseline), 4200 m/13'800 ft and 6000 m/19'700 ft above sea level. RESULTS Arterial oxygen saturation (-13.06% ± 4.69, p = < 0.001; -23.46% ± 5.7,p = < 0.001), retinal venous pressure (+7.16 m Hg±8.2, p = < 0.001;+9.9 mm Hg±8.5, p = < 0.001) and ocular perfusion pressure (-8.49 mm Hg±10.6, p = < 0.001; -6.02 mm hg±11.2, p = 0.006) changed significantly from baseline at both high altitude of 4200 and 6000 m. Intra-ocular pressure did not change significantly at all altitudes (+1.16 mm Hg±4.5, p = 0.227; +0.84 mm Hg±4.8, p = 0.286) and mean arterial pressure changed significantly only at an altitude of 6000 m (+3,8 mm Hg±21.1, p = 0.005) from baseline. CONCLUSION As hypoxia increases with higher altitude, arterial oxygen saturation and ocular perfusion pressure decreased, retinal venous pressure increased, intra-ocular pressure remains stable and mean arterial pressure was elevated only at 6000 m.
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Affiliation(s)
- M Baertschi
- University of Basel, Department of Ophthalmology, Basel, Switzerland.,SALUS University, Philadelphia, PA, USA.,Eyeness AG, Hirschengraben, Bern, Switzerland
| | | | - J Flammer
- University of Basel, Department of Ophthalmology, Basel, Switzerland
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Retinal venous pulsation: Expanding our understanding and use of this enigmatic phenomenon. Prog Retin Eye Res 2016; 55:82-107. [DOI: 10.1016/j.preteyeres.2016.06.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 06/22/2016] [Accepted: 06/30/2016] [Indexed: 11/24/2022]
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Neumann T, Baertschi M, Vilser W, Drinda S, Franz M, Brückmann A, Wolf G, Jung C. Retinal vessel regulation at high altitudes1. Clin Hemorheol Microcirc 2016; 63:281-92. [DOI: 10.3233/ch-162041] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Thomas Neumann
- Department of Internal Medicine III, Jena University Hospital, Jena, Germany
| | - Michael Baertschi
- Department of Ophthalmology, University of Basel, Switzerland
- Eyeness AG, Bern, Switzerland
| | | | | | - Marcus Franz
- Department of Internal Medicine I, Jena University Hospital, Jena, Germany
| | | | - Gunter Wolf
- Department of Internal Medicine III, Jena University Hospital, Jena, Germany
| | - Christian Jung
- University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Medical Faculty, Division of Cardiology, Pulmonology and Vascular Medicine, Düsseldorf, Germany
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Kida T, Flammer J, Oku H, Morishita S, Fukumoto M, Suzuki H, Konieczka K, Ikeda T. Suppressed endothelin-1 by anti-VEGF therapy is important for patients with BRVO-related macular edema to improve their vision. EPMA J 2016; 7:18. [PMID: 27559424 PMCID: PMC4995759 DOI: 10.1186/s13167-016-0066-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 06/28/2016] [Indexed: 12/16/2022]
Abstract
Background Branch retinal vein occlusion (BRVO) commonly occurs at the arteriovenous crossing in the unilateral eye, and cardiovascular diseases can be risk factors of BRVO. However, the pathomechanism leading to BRVO is not yet clear. In addition to mechanical compression, the vein might locally constrict due to an altered biochemical environment, such as an increase in the concentration of endothelin-1 (ET-1). We evaluated changes in ET-1 following injection of intravitreal bevacizumab (IVB), which is the anti-vascular endothelial growth factor (VEGF) agent with the longest serum half-life, to determine the effect on BRVO-related macular edema. Methods Twenty consecutive patients with BRVO-related macular edema (10 males, 10 females; age range 56–83 years) who visited our hospital were included in this prospective study. Visual acuity (VA); central retinal thickness (CRT), determined by macular optical coherence tomography (OCT); and plasma ET-1 levels were obtained before IVB treatment and 1 month later. Results Patients had hypertension (80 %), dyslipidemia (50 %), diabetes mellitus (35 %), or collagen disease (5 %). Mean CRT was significantly decreased from 673.0 ± 327.8 to 388.2 ± 155.0 μm (P = 0.0007), and mean VA was significantly improved after IVB (P = 0.0239). Mean plasma ET-1 was significantly decreased from 1.272 ± 0.451 to 1.095 ± 0.316 pg/mL (P = 0.0238); however, the plasma ET-1 level was increased in all five patients who did not show improved VA after IVB. Conclusions In patients with BRVO-related macular edema, anti-VEGF therapy leads to an expected reduction in ET-1 levels; however, the ET-1 level was found to increase in some patients; this is clearly related to less improvement of VA after anti-VEGF therapy. Trial registration University hospital Medical Information Network (UMIN) Center UMIN000013236. Registered 10 October, 2012.
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Affiliation(s)
- Teruyo Kida
- Department of Ophthalmology, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686 Japan
| | - Josef Flammer
- Department of Ophthalmology, University of Basel, Basel, Switzerland
| | - Hidehiro Oku
- Department of Ophthalmology, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686 Japan
| | - Seita Morishita
- Department of Ophthalmology, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686 Japan
| | - Masanori Fukumoto
- Department of Ophthalmology, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686 Japan
| | - Hiroyuki Suzuki
- Department of Ophthalmology, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686 Japan
| | | | - Tsunehiko Ikeda
- Department of Ophthalmology, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686 Japan
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Abstract
The retinal venous pressure (RVP) can be measured non-invasively. While RVP is equal to or slightly above intraocular pressure (IOP) in healthy people, it is often markedly increased in patients with eye or systemic diseases. Beside a mechanical obstruction, the main cause of such an elevation is a local dysregulation of a retinal vein, particularly a constriction induced by endothelin-1 (ET-1). A local increase of ET-1 can result from a high plasma level, as ET-1 can diffuse from the fenestrated capillaries of the choroid into the optic nerve head (ONH), bypassing the blood retinal barrier. A local increase can also result from increased local production either by a sick neighboring artery or retinal tissue. Generally, the main factors increasing ET-1 are inflammations and hypoxia, either locally or in a remote organ. RVP is known to be increased in patients with glaucoma, retinal vein occlusion (RVO), diabetic retinopathy, high mountain disease, and primary vascular dysregulation (PVD). PVD is the major vascular component of Flammer syndrome (FS). An increase of RVP decreases perfusion pressure, which heightens the risk for hypoxia. An increase of RVP also elevates transmural pressure, which in turn heightens the risk for retinal edema. In patients with RVO, a high level of RVP may not only be a consequence but also a potential cause of the occlusion; therefore, it risks causing a vicious circle. Narrow retinal arteries and particularly dilated retinal veins are known risk indicators for future cardiovascular events. As the major cause for such a retinal venous dilatation is an increased RVP, RVP may likely turn out to be an even stronger predictor.
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Affiliation(s)
- Josef Flammer
- Department of Ophthalmology, University of Basel, Mittlere Strasse 91, CH-4031 Basel, Switzerland
| | - Katarzyna Konieczka
- Department of Ophthalmology, University of Basel, Mittlere Strasse 91, CH-4031 Basel, Switzerland
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