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Iwase C, Iwase T, Tomita R, Akahori T, Yamamoto K, Ra E, Terasaki H. Changes in pulse waveforms in response to intraocular pressure elevation determined by laser speckle flowgraphy in healthy subjects. BMC Ophthalmol 2021; 21:303. [PMID: 34416871 PMCID: PMC8379756 DOI: 10.1186/s12886-021-02070-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 08/14/2021] [Indexed: 11/27/2022] Open
Abstract
Background The influences of intraocular pressure (IOP) elevations on the pulse waveform in the optic nerve head (ONH) were evaluated using laser speckle flowgraphy (LSFG) in normal subjects. Methods This prospective cross-sectional study was conducted at the Nagoya University Hospital. An ophthalmodynamometer was pressed on the sclera to increase the IOP by 20 mmHg or 30 mmHg for 1 min (experiment 1, 16 subjects) and by 30 mmHg for 10 min (experiment 2, 10 subjects). The mean blur rate (MBR) and the eight pulse waveform parameters determined using LSFG were measured before, immediately after and during an IOP elevation, and after the IOP returned to the baseline pressure. Results A significant elevation in the IOP and a significant reduction in the ocular perfusion pressure (OPP) were found after applying the ophthalmodynamometer (both, P < 0.001). The blowout score (BOS) reduced significantly (P < 0.001), and the flow acceleration index (FAI; P < 0.01) and resistivity index (RI; P < 0.001) increased significantly immediately after increasing the IOP by 20 or 30 mmHg (experiment 1). The BOS reduced significantly (P < 0.001), and the FAI (P < 0.01) and RI (P < 0.001) increased significantly after the IOP elevation by 30 mmHg in both experiment 2 and 1. However, the BOS and RI recovered significantly at time 10 compared to that in time 0 (immediately after IOP elevation) during the 10-min IOP elevation (P < 0.001 and P = 0.008, respectively). Conclusions In conclusion, the BOS, FAI, and RI of the pulse waveforms changed significantly with an acute elevation in the IOP. The change should be related to the larger difference between the maximum and minimum MBRs during the IOP elevation.
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Affiliation(s)
- Chie Iwase
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan. .,Department of Ophthalmology, Akita University Graduate School of Medicine, 1-1-1 Hondou, Akita-city, Akita, 010-8543, Japan.
| | - Takeshi Iwase
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Department of Ophthalmology, Akita University Graduate School of Medicine, 1-1-1 Hondou, Akita-city, Akita, 010-8543, Japan
| | - Ryo Tomita
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Tomohiko Akahori
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Kentaro Yamamoto
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Eimei Ra
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Hiroko Terasaki
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
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Yang H, Luo H, Gardiner SK, Hardin C, Sharpe GP, Caprioli J, Demirel S, Girkin CA, Liebmann JM, Mardin CY, Quigley HA, Scheuerle AF, Fortune B, Chauhan BC, Burgoyne CF. Factors Influencing Optical Coherence Tomography Peripapillary Choroidal Thickness: A Multicenter Study. Invest Ophthalmol Vis Sci 2019; 60:795-806. [PMID: 30811523 PMCID: PMC6392476 DOI: 10.1167/iovs.18-25407] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Purpose To quantify peripapillary choroidal thickness (PCT) and the factors that influence it in healthy participants who represent the racial and ethnic composition of the U.S. population. Methods A total of 362 healthy participants underwent optical coherence tomography (OCT) enhanced depth imaging of the optic nerve head with a 24 radial B-scan pattern aligned to the fovea to Bruch's membrane opening axis. Bruch's membrane, anterior scleral canal opening (ASCO), and the anterior scleral surface were manually segmented. PCT was measured at 100, 300, 500, 700, 900, and 1100 μm from the ASCO globally and within 12 clock-hour sectors. The effects of age, axial length, intraocular pressure, ethnicity, sex, sector, and ASCO area on PCT were assessed by ANOVA and univariable and multivariable regressions. Results Globally, PCT was thicker further from the ASCO border and thinner with older age, longer axial length, larger ASCO area, European descent, and female sex. Among these effectors, age and axial length explained the greatest proportion of variance. The rate of age-related decline increased further from the ASCO border. Sectorally, the inferior-temporal sectors were thinnest (10.7%-20.0% thinner than the thickest sector) and demonstrated a higher rate of age-related loss (from 15.6% to 20.7% faster) at each ASCO distance. Conclusions In healthy eyes, PCT was thinnest in the inferior temporal sectors and thinner PCT was associated with older age, European descent, longer axial length, larger ASCO area, and female sex. Among these associations, age had the strongest influence, and its effect was greatest within the inferior temporal sectors.
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Affiliation(s)
- Hongli Yang
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, Oregon, United States
| | - Haomin Luo
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, Oregon, United States.,Department of Ophthalmology, Second Xiangya Hospital, Central South University, Changsha, Hunan Province, People's Republic of China
| | - Stuart K Gardiner
- Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, Oregon, United States
| | - Christy Hardin
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, Oregon, United States
| | - Glen P Sharpe
- Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Joseph Caprioli
- Jules Stein Eye Institute, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California, United States
| | - Shaban Demirel
- Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, Oregon, United States
| | - Christopher A Girkin
- Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Jeffrey M Liebmann
- Einhorn Clinical Research Center, Moise and Chella Safra Advanced Ocular Imaging Laboratory, New York Eye and Ear Infirmary of Mount Sinai Health System, New York, United States
| | | | - Harry A Quigley
- Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland, United States
| | | | - Brad Fortune
- Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, Oregon, United States
| | - Balwantray C Chauhan
- Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Claude F Burgoyne
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, Oregon, United States
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3
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Chung JF, Lee SJ, Sood AK. Immunological consequences of ageing microvascular hemodynamic changes in view of cancer development and treatment. Oncotarget 2017; 8:69047-69061. [PMID: 28978180 PMCID: PMC5620320 DOI: 10.18632/oncotarget.17749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 04/24/2017] [Indexed: 11/25/2022] Open
Abstract
Risk factors of cardiovascular diseases have long been implicated as risk factors for carcinogenesis, but clear explanations for their association have not been presented. In this article, fundamental concepts from carcinogenesis, microvascular hemodynamics, and immunity are collectively reviewed and analyzed in context of the known features of vascular ageing effects, in formulating a theory that suggests reduced microvascular immunity as an important driving factor for carcinogenesis. Furthermore, scientific, preclinical, and clinical evidence that support this new theory are presented in an interdisciplinary manner, offering new explanations to previously unanswered factors that impact cancer risks and its treatment outcome such as chronic drug use, temperature, stress and exercise effects among others. Forward-looking topics discussing the implications of this new idea to cancer immunotherapeutics are also discussed.
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Affiliation(s)
| | - Sang Joon Lee
- Division of Integrative Biosciences and Biotechnology (IBB), Pohang University of Science and Technology (POSTECH), Pohang, South Korea.,Center for Biofluid and Biomimic Research, Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, South Korea
| | - Anil K Sood
- Departments of Gynecologic Oncology and Reproductive Medicine and Cancer Biology, The University of Texas, MD Anderson Cancer Center, Houston, TX, USA.,Center for RNA Interference and Non-Coding RNAs, The University of Texas, MD Anderson Cancer Center, Houston, TX, USA
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4
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Yang H, Reynaud J, Lockwood H, Williams G, Hardin C, Reyes L, Stowell C, Gardiner SK, Burgoyne CF. The connective tissue phenotype of glaucomatous cupping in the monkey eye - Clinical and research implications. Prog Retin Eye Res 2017; 59:1-52. [PMID: 28300644 PMCID: PMC5603293 DOI: 10.1016/j.preteyeres.2017.03.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 02/14/2017] [Accepted: 03/06/2017] [Indexed: 10/20/2022]
Abstract
In a series of previous publications we have proposed a framework for conceptualizing the optic nerve head (ONH) as a biomechanical structure. That framework proposes important roles for intraocular pressure (IOP), IOP-related stress and strain, cerebrospinal fluid pressure (CSFp), systemic and ocular determinants of blood flow, inflammation, auto-immunity, genetics, and other non-IOP related risk factors in the physiology of ONH aging and the pathophysiology of glaucomatous damage to the ONH. The present report summarizes 20 years of technique development and study results pertinent to the characterization of ONH connective tissue deformation and remodeling in the unilateral monkey experimental glaucoma (EG) model. In it we propose that the defining pathophysiology of a glaucomatous optic neuropathy involves deformation, remodeling, and mechanical failure of the ONH connective tissues. We view this as an active process, driven by astrocyte, microglial, fibroblast and oligodendrocyte mechanobiology. These cells, and the connective tissue phenomena they propagate, have primary and secondary effects on retinal ganglion cell (RGC) axon, laminar beam and retrolaminar capillary homeostasis that may initially be "protective" but eventually lead to RGC axonal injury, repair and/or cell death. The primary goal of this report is to summarize our 3D histomorphometric and optical coherence tomography (OCT)-based evidence for the early onset and progression of ONH connective tissue deformation and remodeling in monkey EG. A second goal is to explain the importance of including ONH connective tissue processes in characterizing the phenotype of a glaucomatous optic neuropathy in all species. A third goal is to summarize our current efforts to move from ONH morphology to the cell biology of connective tissue remodeling and axonal insult early in the disease. A final goal is to facilitate the translation of our findings and ideas into neuroprotective interventions that target these ONH phenomena for therapeutic effect.
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Affiliation(s)
- Hongli Yang
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, OR, United States; Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, OR, United States
| | - Juan Reynaud
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, OR, United States; Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, OR, United States
| | - Howard Lockwood
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, OR, United States; Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, OR, United States
| | - Galen Williams
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, OR, United States; Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, OR, United States
| | - Christy Hardin
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, OR, United States; Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, OR, United States
| | - Luke Reyes
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, OR, United States; Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, OR, United States
| | - Cheri Stowell
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, OR, United States; Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, OR, United States
| | - Stuart K Gardiner
- Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, OR, United States
| | - Claude F Burgoyne
- Devers Eye Institute, Optic Nerve Head Research Laboratory, Legacy Research Institute, Portland, OR, United States; Devers Eye Institute, Discoveries in Sight Research Laboratories, Legacy Research Institute, Portland, OR, United States.
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5
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Geyman LS, Garg RA, Suwan Y, Trivedi V, Krawitz BD, Mo S, Pinhas A, Tantraworasin A, Chui TYP, Ritch R, Rosen RB. Peripapillary perfused capillary density in primary open-angle glaucoma across disease stage:an optical coherence tomography angiography study. Br J Ophthalmol 2017; 101:1261-1268. [DOI: 10.1136/bjophthalmol-2016-309642] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Revised: 12/21/2016] [Accepted: 01/08/2017] [Indexed: 11/04/2022]
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6
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The non-human primate experimental glaucoma model. Exp Eye Res 2015; 141:57-73. [PMID: 26070984 DOI: 10.1016/j.exer.2015.06.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 06/03/2015] [Accepted: 06/06/2015] [Indexed: 01/05/2023]
Abstract
The purpose of this report is to summarize the current strengths and weaknesses of the non-human primate (NHP) experimental glaucoma (EG) model through sections devoted to its history, methods, important findings, alternative optic neuropathy models and future directions. NHP EG has become well established for studying human glaucoma in part because the NHP optic nerve head (ONH) shares a close anatomic association with the human ONH and because it provides the only means of systematically studying the very earliest visual system responses to chronic intraocular pressure (IOP) elevation, i.e. the conversion from ocular hypertension to glaucomatous damage. However, NHPs are impractical for studies that require large animal numbers, demonstrate spontaneous glaucoma only rarely, do not currently provide a model of the neuropathy at normal levels of IOP, and cannot easily be genetically manipulated, except through tissue-specific, viral vectors. The goal of this summary is to direct NHP EG and non-NHP EG investigators to the previous, current and future accomplishment of clinically relevant knowledge in this model.
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7
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See JLS, Yang M, Loh A, Goh KY. Clinical Ophthalmic Presentations of Central Neurocytoma. Neuroophthalmology 2006. [DOI: 10.1080/01658100601025514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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8
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Abstract
In the recent past there has been great interest in the blood supply of the optic nerve head (ONH), how to evaluate ONH blood flow, and what factors influence it, in health and disease. This is because evidence has progressively accumulated that there is vascular insufficiency in the ONH in both anterior ischemic optic neuropathy (AION) and glaucomatous optic neuropathy (GON)-two major causes of blindness or of seriously impaired vision in man. For the management and prevention of visual loss in these two disorders, a proper understanding of the factors that influence the blood flow in the ONH is essential. The objective of this paper is, therefore, to review and discuss all these factors. The various factors that influence the vascular resistance, mean blood pressure and intraocular pressure are discussed, to create a better basic understanding of the ONH blood flow, which may help us toward a logical strategy for prevention and management of ischemic disorders of the ONH.
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Affiliation(s)
- S S Hayreh
- Department of Ophthalmology and Visual Sciences, University of Iowa College of Medicine, Iowa City, IA 52242-1091, USA.
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9
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Cheng CY, Liu CJ, Chiou HJ, Chou JC, Hsu WM, Liu JH. Color Doppler imaging study of retrobulbar hemodynamics in chronic angle-closure glaucoma. Ophthalmology 2001; 108:1445-51. [PMID: 11470698 DOI: 10.1016/s0161-6420(01)00603-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To evaluate the retrobulbar hemodynamics in patients with chronic angle-closure glaucoma (CACG) by using color Doppler imaging (CDI) and to correlate the degree of glaucomatous visual field loss with the hemodynamic parameters. DESIGN Prospective case series. PARTICIPANTS AND CONTROLS Twenty-six Chinese patients with CACG and 26 age-matched and gender-matched normal subjects were recruited. All CACG patients had history of chronic intraocular pressure (IOP) elevation and asymmetric visual field defects between their fellow eyes. After receiving laser peripheral iridotomy and/or filtration surgery, all of them had bilateral medication-free controlled IOP before enrolling into the study. METHODS Each subject underwent CDI measurement in the central retinal artery (CRA) and the nasal and temporal short posterior ciliary arteries (PCA). Visual fields of the CACG patients were obtained with Humphrey 24-2 program. The visual field defects were scored with the Advanced Glaucoma Intervention Study (AGIS) system. For each CACG patient, the eye with lower AGIS score was defined as the better eye and the eye with higher score as the worse eye. MAIN OUTCOME MEASURES Peak-systolic velocity (PSV), end-diastolic velocity (EDV) and resistance index (RI) were determined. RESULTS The EDV in the CRA and the temporal PCA was decreased significantly (P = 0.041 and 0.023, respectively) in the worse eyes of CACG patients compared with those in the control eyes. The better eyes of CACG patients showed no significant change in hemodynamic parameters compared with the control eyes. While comparing the fellow eyes of CACG patients, the worse eyes had significantly lower EDV in the temporal PCA (P = 0.012) than the contralateral better eyes. In 11 CACG patients with a difference of at least 8 in AGIS visual field scores between their fellow eyes, the worse eyes had significantly lower EDV (P = 0.041) in the CRA and lower PSV (P = 0.018) and EDV (P = 0.018) in the temporal PCA compared with those in the contralateral eyes. In multivariate regression analysis, the AGIS scores were significantly correlated with the PSV in the CRA (P = 0.015) and with the EDV (P < 0.001) and RI (P = 0.027) in the temporal PCA in patients with CACG. CONCLUSIONS Patients with well-controlled CACG may have decreased retrobulbar blood flow velocities and increased vascular resistance in the CRA and temporal PCA. The degree of retrobulbar hemodynamic impairment was well correlated with the degree of glaucomatous visual field loss.
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Affiliation(s)
- C Y Cheng
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan
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10
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Duijm HF, Berg TJ, Greve EL. Central and peripheral arteriovenous passage times of the retina in glaucoma. Exp Eye Res 1999; 69:145-53. [PMID: 10433851 DOI: 10.1006/exer.1999.0683] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The purpose of this paper was to estimate arteriovenous passage (AVP) times, taking into account the non-uniform distribution of arrival times over the vessel diameter, and assessment of respective differences between 15 normal controls (N), 30 primary open-angle glaucoma (POAG) and 30 normal-pressure glaucoma (NPG) patients. Arrival times in retinal vessels were assessed from digitized scanning laser fluorescein angiograms. The arrival times were assessed as a function of position (juxtamural versus axial) in the vessel. This differentiation, based on the measurement position in the vessel, enabled the estimation of AVP times of the posterior pole and of the peripheral retina. The overall, juxtamural and axial AVP times were prolonged in POAG as compared to both N and NPG (P<0.03). The difference in axial AVP times between POAG and normal subjects was considerably larger than the juxtamural values. The distribution of AVP times was considerably larger in POAG patients than in N subjects and NPG patients. Retinal AVP times are prolonged in POAG patients as compared to N and NPG. The wider distribution of AVP times in POAG patients may point to a generalized microvascular alteration. Since the axial AVP times seem to provide the largest differences between NPG and POAG patients, this measurement may be preferred over more general AVP times. The axial AVP times may possibly reflect peripheral vascular changes, e.g. increased vascular resistance. The underlying mechanisms causing these differences are at present unknown.
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Affiliation(s)
- H F Duijm
- Department of Ophthalmology, Academic Medical Center, University of Amsterdam, The Netherlands
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Liu CJ, Chou YH, Chou JC, Chiou HJ, Chiang SC, Liu JH. Retrobulbar haemodynamic changes studied by colour Doppler imaging in glaucoma. Eye (Lond) 1998; 11 ( Pt 6):818-26. [PMID: 9537138 DOI: 10.1038/eye.1997.212] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
PURPOSE To determine the effect of spontaneously elevated intraocular pressure (IOP) on the ocular circulation, and evaluate the result of IOP-lowering procedures in terms of haemodynamics. METHODS Colour Doppler imaging (CDI) was employed to determine the peak systolic velocity (PSV), end-diastolic velocity (EDV) and time average maximal velocity (TAMV), as well as the Pourcelot ratio (PR) and pulsatility index (PI), of the central retinal artery (CRA), posterior ciliary arteries (PCA) and ophthalmic artery. Various CDI parameters of the eyes with elevated IOP were compared with those of the clinically healthy fellow eyes and the control eyes, separately. Also, data from CDI of glaucoma eyes obtained during the period of elevated IOP and then following IOP-lowering procedures were compared, deliberately avoiding the influence of glaucoma medications. RESULTS Eyes (n = 12) with elevated IOP showed significantly decreased flow velocities of the CRA and significantly increased PR and PI of the nasal and temporal PCA, compared with the fellow and control eyes, respectively. Following IOP-lowering procedures, the PR and PI of the nasal PCA decreased significantly. CONCLUSION Spontaneously elevated IOP may induce haemodynamic changes in the CRA and PCA, but no significant change is identified in the ophthalmic artery. Flow velocities tend to decrease while the resistance indices tend to increase with elevated IOP. Such haemodynamic changes may reverse following normalisation of IOP.
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Affiliation(s)
- C J Liu
- Department of Ophthalmology, Veterans General Hospital-Taipei, Taiwan
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12
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Ben-Nun J, Nemet P. Intraocular pressure and blood flow of the optic disk: a fluorescent blood cell angiography study. Surv Ophthalmol 1995; 39 Suppl 1:S33-9. [PMID: 7660311 DOI: 10.1016/s0039-6257(05)80071-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The damage to disk microcirculation in glaucoma and ocular hypertension is correlated with the damage to the neuronal tissue. However, it is not clear whether the primary damage is vascular or neurogenic. We have developed a new method which allows in vivo observation of the retinal capillary blood cell flow and the plasma flow, separately. The method was used to examine the blood cell flow in the optic disks of cats' eyes. The intraocular pressure was controlled by extra-fine intraocular canula at the anterior chamber. It was found that blood cell flow became stagnant in a few capillaries at the optic disk with an intraocular pressure of 30-45% of the systemic mean blood pressure. When an induced IOP increase to 45% of systemic mean blood pressure was sustained for 30 minutes, microcirculatory blood flow recovery was complete two hours later. When this pressure was sustained for 120 minutes, the recovery was incomplete two hours later. This work represents a new tool in the research of retinal and disk hemodynamics and microvascular pathologies. The results presented in this paper support the hypothesis that early ischemic microdamage might be the basis of the pathogenesis of the chronic glaucomas.
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Affiliation(s)
- J Ben-Nun
- Eye Department, Assaff-Hroffee Medical Center, Tzriffin, Israel
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Wolf S, Arend O, Sponsel WE, Schulte K, Cantor LB, Reim M. Retinal hemodynamics using scanning laser ophthalmoscopy and hemorheology in chronic open-angle glaucoma. Ophthalmology 1993; 100:1561-6. [PMID: 8414416 DOI: 10.1016/s0161-6420(93)31444-2] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
PURPOSE Recent studies suggest that elevated intraocular pressure is not the only causative factor for the development of visual field loss and optic nerve damage in glaucomatous eyes. The authors determine whether retinal hemodynamics or blood fluidity are alternated in eyes of patients with open-angle glaucoma compared with those of age- and sex-matched healthy subjects. METHOD High-quality video fluorescein angiograms were obtained from single eyes of 51 patients with chronic open-angle glaucoma. From these angiograms, the arm-retina time, mean dye velocity, and arteriovenous passage time were quantified. The data from patients were compared with those of an age- and sex-matched group of healthy subjects. RESULTS In patients with chronic open-angle glaucoma, an 11% reduction of the mean dye velocity (P < 0.05) and a 41% prolongation of the arteriovenous passage time (P < 0.01) was observed relative to the values obtained among the control subjects. Among hematocrit values, plasma viscosity, and erythrocyte aggregation, only plasma viscosity showed a significant increase (4%; P < 0.01) in patients with chronic open-angle glaucoma. CONCLUSION These results indicate that a pronounced circulatory deficit exists within the retinal vasculature of glaucomatous eyes, which may coexist with, but cannot be fully attributed to, an increase in plasma viscosity.
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Affiliation(s)
- S Wolf
- Augenklinik der Medizinische Fakultät, Rheinisch-Westfälischen Technischen Hochschule Aachen, Germany
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Kubota T, von Below H, Holbach LM, Naumann GO. Bilateral cavernous degeneration of the optic nerve associated with multiple arteriosclerotic ischemic infarctions. Graefes Arch Clin Exp Ophthalmol 1993; 231:52-5. [PMID: 8428682 DOI: 10.1007/bf01681702] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Affiliation(s)
- T Kubota
- Augenklinik Universität Erlangen-Nürnberg, Federal Republic of Germany
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Abstract
The pathogenesis of the transient obscurations of vision that occur with papilledema is a subject of speculation and debate. We present four examples of transient obscurations of vision that were clinically indistinguishable from those of papilledema; they occurred in patients with elevated optic discs from causes not related to increased intracranial pressure. The underlying mechanism for visual obscurations in all of these patients appear to be transient ischemia of the optic nerve head consequent to increased tissue pressure. Axonal swelling, intraneural masses, and increased influx of interstitial fluid may all contribute to increases in tissue pressure in the optic nerve head. The consequent reduction in perfusion pressure renders the small, low-pressure vessels that supply the optic nerve head vulnerable to compromise. Brief fluctuations in intracranial or systemic blood pressure may then result in transient loss of function in the eyes. We postulate that such mechanisms may apply in all cases of optic disc elevation, including papilledema.
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16
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Nakashima T, Ito A. Effect of increased perilymphatic pressure on endocochlear potential. Ann Otol Rhinol Laryngol 1981; 90:264-6. [PMID: 7271132 DOI: 10.1177/000348948109000314] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A study was done to determine how increased fluid pressure in the inner ear influences cochlear blood flow. Hydrostatic pressure was applied to the scala vestibuli or scala tympani in guinea pigs. Endocochlear potential, which is sensitive to the lack of oxygen, was measured through the round window membrane or through the stria vascularis. Cochlear blood flow was confirmed by intravenous injection of India ink. When the perilymphatic pressure was raised to a relatively high level, endocochlear potential decreased, ina similar way as in response to anoxia, because of the cessation of the cochlear blood flow. This change was completely reversible upon applications of pressure for brief periods of time. We consider that the cochlear blood flow ceases when the fluid pressure reaches the level of intracochlear arterial pressure.
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17
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Gibson A. The Incidence, Heredity and Aetiology of Open Angle Glaucoma. Clin Exp Optom 1980. [DOI: 10.1111/j.1444-0938.1980.tb01940.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Best M, Blumenthal M, Galin MA, Toyofuku H. Fluorescein angiography during induced ocular hypertension in glaucoma. Br J Ophthalmol 1972; 56:6-12. [PMID: 5058721 PMCID: PMC1208642 DOI: 10.1136/bjo.56.1.6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Blumenthal M, Best M, Galin MA, Gitter KA. Ocular circulation: analysis of the effect of induced ocular hypertension on reginal and choroidal blood flow in man. Am J Ophthalmol 1971; 71:819-25. [PMID: 5553011 DOI: 10.1016/0002-9394(71)90247-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Anderson DR. Experimental alpha chymotrypsin glaucoma studied by scanning electron microscopy. Am J Ophthalmol 1971; 71:470-6. [PMID: 4993915 DOI: 10.1016/0002-9394(71)90120-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Rosen ES, Boyd TA. New method of assessing choroidal ischemia in open-angle glaucoma and ocular hypertension. Am J Ophthalmol 1970; 70:912-21. [PMID: 5490619 DOI: 10.1016/0002-9394(70)92467-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Blumenthal M, Gitter KA, Best M, Galin MA. Fluorescein angiography during induced ocular hypertension in man. Am J Ophthalmol 1970; 69:39-43. [PMID: 5411659 DOI: 10.1016/0002-9394(70)91854-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Hayreh SS. Blood supply of the optic nerve head and its role in optic atrophy, glaucoma, and oedema of the optic disc. Br J Ophthalmol 1969; 53:721-48. [PMID: 4982590 PMCID: PMC506749 DOI: 10.1136/bjo.53.11.721] [Citation(s) in RCA: 445] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Ernest JT, Potts AM. Pathophysiology of the distal portion of the optic nerve. 3. Effect of intraocular pressure on optic nerve discharge. Am J Ophthalmol 1969; 68:594-604. [PMID: 5344323 DOI: 10.1016/0002-9394(69)91238-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Ernest JT, Potts AM. Pathophysiology of the distal portion of the optic nerve. II. Vascular relationships. Am J Ophthalmol 1968; 66:380-7. [PMID: 4970984 DOI: 10.1016/0002-9394(68)91521-3] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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