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El Hoffy NM, Abdel Azim EA, Hathout RM, Fouly MA, Elkheshen SA. Glaucoma: Management and Future Perspectives for Nanotechnology-Based Treatment Modalities. Eur J Pharm Sci 2020; 158:105648. [PMID: 33227347 DOI: 10.1016/j.ejps.2020.105648] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 09/12/2020] [Accepted: 11/13/2020] [Indexed: 12/11/2022]
Abstract
Glaucoma, being asymptomatic for relatively late stage, is recognized as a worldwide cause of irreversible vision loss. The eye is an impervious organ that exhibits natural anatomical and physiological barriers which renders the design of an efficient ocular delivery system a formidable task and challenge scientists to find alternative formulation approaches. In the field of glaucoma treatment, smart delivery systems for targeting have aroused interest in the topical ocular delivery field owing to its potentiality to oppress many treatment challenges associated with many of glaucoma types. The current momentum of nano-pharmaceuticals, in the development of advanced drug delivery systems, hold promises for much improved therapies for glaucoma to reduce its impact on vision loss. In this review, a brief about glaucoma; its etiology, predisposing factors and different treatment modalities has been reviewed. The diverse ocular drug delivery systems currently available or under investigations have been presented. Additionally, future foreseeing of new drug delivery systems that may represent potential means for more efficient glaucoma management are overviewed. Finally, a gab-analysis for the required investigation to pave the road for commercialization of ocular novel-delivery systems based on the nano-technology are discussed.
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Affiliation(s)
- Nada M El Hoffy
- Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmaceutical Sciences and Pharmaceutical Industries, Future University in Egypt
| | - Engy A Abdel Azim
- Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmaceutical Sciences and Pharmaceutical Industries, Future University in Egypt
| | - Rania M Hathout
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
| | | | - Seham A Elkheshen
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Cairo, Egypt.
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Wang MY, Brewer R, Sadun AA. Posterior ischemic optic neuropathy: Perioperative risk factors. Taiwan J Ophthalmol 2020; 10:167-173. [PMID: 33110746 PMCID: PMC7585472 DOI: 10.4103/tjo.tjo_41_20] [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: 06/16/2020] [Accepted: 06/29/2020] [Indexed: 11/04/2022] Open
Abstract
Perioperative posterior ischemic optic neuropathy (PION) is a rare but devastating condition. Visual impairment is commonly bilateral, profound, and irreversible. The most frequently associated triggering events are spine surgeries, other orthopedic surgeries, cardiac bypass surgeries, and radical neck dissection. The etiology is multifactorial. The most commonly reported risk factors are severe and prolonged hypotension, anemia, hemodilution, orbital and periorbital edema, direct orbital compression by prone position, and abnormal autoregulation. This review discusses the current literature on perioperative PION and includes a study conducted by our group to investigate the perioperative risk factors of PION in order to better understand the pathogenesis and help identify high-risk patients. Our results provide further corroborating evidence that PION is associated with spinal, cardiovascular, and abdominal surgeries, longer duration of procedure, and facial edema. Anemia and chronic hypertension are frequent risk factors. Treatment for perioperative PION is uncertain and depends largely on the immediate reversal of hemodynamic alterations. Hence, it is important to identify patients at risk and accordingly take prophylactic measures to prevent its occurrence. Optimizing hemoglobin levels, hemodynamic status, and tissue oxygenation is crucial.
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Affiliation(s)
- Michelle Y Wang
- Department of Ophthalmology, Southern California Permanente Medical Group, Los Angeles, California, USA
| | - Ryan Brewer
- San Antonio Health Science Center and San Antonio Uniformed Services Health Education Consortium, University of Texas, Austin, Texas, USA
| | - Alfredo A Sadun
- Department of Ophthalmology, Doheny Eye Institute, UCLA, Pasadena, California, USA
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3
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[Acute ischemic optic nerve disease: Pathophysiology, clinical features and management (French translation of the article)]. J Fr Ophtalmol 2020; 43:256-270. [PMID: 32057527 DOI: 10.1016/j.jfo.2019.03.040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 03/28/2019] [Indexed: 11/23/2022]
Abstract
Ischemic optic neuropathies are among the leading causes of severe visual acuity loss in people over 50 years of age. They constitute a set of various entities that are clinically, etiologically and therapeutically different. Anatomically, it is necessary to distinguish anterior and posterior forms. From an etiological point of view, the diagnosis of the arteritic form due to giant cell arteritis requires emergent management to prevent blindness and even death in the absence of prompt corticosteroid treatment. When this diagnosis has been ruled out with certainty, non-arteritic ischemic optic neuropathies represent a vast etiological context that in the majority of cases involves a local predisposing factor (small optic nerves, disc drusen) with a precipitating factor (severe hypotension, general anesthesia or dialysis) in a context of vascular disease (sleep apnea syndrome, hypertension, diabetes, etc.). In the absence of specific available treatment, it is the responsibility of the clinician to identify the risk factors involved, in order to reduce the risk of contralateral recurrence that may occur even several years later. Due to their complexity, these pathologies are the subject of debates regarding both the pathophysiological and therapeutic perspectives; this review aims to provide a synthesis of validated knowledge while discussing controversial data.
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Augstburger E, Héron E, Abanou A, Habas C, Baudouin C, Labbé A. Acute ischemic optic nerve disease: Pathophysiology, clinical features and management. J Fr Ophtalmol 2020; 43:e41-e54. [PMID: 31952875 DOI: 10.1016/j.jfo.2019.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 12/18/2019] [Indexed: 11/28/2022]
Abstract
Ischemic optic neuropathies are among the leading causes of severe visual acuity loss in people over 50 years of age. They constitute a set of various entities that are clinically, etiologically and therapeutically different. Anatomically, it is necessary to distinguish anterior and posterior forms. From an etiological point of view, the diagnosis of the arteritic form due to giant cell arteritis requires emergent management to prevent blindness and even death in the absence of prompt corticosteroid treatment. When this diagnosis has been ruled out with certainty, non-arteritic ischemic optic neuropathies represent a vast etiological context that in the majority of cases involves a local predisposing factor (small optic nerves, disc drusen) with a precipitating factor (severe hypotension, general anesthesia or dialysis) in a context of vascular disease (sleep apnea syndrome, hypertension, diabetes, etc.). In the absence of specific available treatment, it is the responsibility of the clinician to identify the risk factors involved, in order to reduce the risk of contralateral recurrence that may occur even several years later. Due to their complexity, these pathologies are the subject of debates regarding both the pathophysiological and therapeutic perspectives; this review aims to provide a synthesis of validated knowledge while discussing controversial data.
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Affiliation(s)
- E Augstburger
- Ophthalmology Service III, CHNO des Quinze-Vingts, IHU FOReSIGHT, 28, rue de Charenton, 75012 Paris, France
| | - E Héron
- Internal medicine service, CHNO des Quinze-Vingts, Paris, France
| | - A Abanou
- Neuroradiology center, CHNO des Quinze-Vingts, Paris, France
| | - C Habas
- Neuroradiology center, CHNO des Quinze-Vingts, Paris, France; Inserm, U968; Inserm-DHOS CIC 503, UPMC Univ Paris 06, UMR_S968, CNRS, UMR 7210, institut de la Vision, CHNO des Quinze-Vingts, Paris, France
| | - C Baudouin
- Ophthalmology Service III, CHNO des Quinze-Vingts, IHU FOReSIGHT, 28, rue de Charenton, 75012 Paris, France; Inserm-DHOS CIC 1423, CHNO des Quinze-Vingts, IHU FOReSIGHT, Paris, France; Inserm, U968; Inserm-DHOS CIC 503, UPMC Univ Paris 06, UMR_S968, CNRS, UMR 7210, institut de la Vision, CHNO des Quinze-Vingts, Paris, France; Ophthalmology service, université de Versailles Saint-Quentin-en-Yvelines, hôpital Ambroise-Paré, AP-HP, Versailles, France
| | - A Labbé
- Ophthalmology Service III, CHNO des Quinze-Vingts, IHU FOReSIGHT, 28, rue de Charenton, 75012 Paris, France; Inserm-DHOS CIC 1423, CHNO des Quinze-Vingts, IHU FOReSIGHT, Paris, France; Inserm, U968; Inserm-DHOS CIC 503, UPMC Univ Paris 06, UMR_S968, CNRS, UMR 7210, institut de la Vision, CHNO des Quinze-Vingts, Paris, France; Ophthalmology service, université de Versailles Saint-Quentin-en-Yvelines, hôpital Ambroise-Paré, AP-HP, Versailles, France.
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Greenberg R, Tymms A. Alert for Perioperative Visual Loss: An Unusual Presentation of an Orbital Haemangioma during Spinal Surgery. Anaesth Intensive Care 2019; 31:679-82. [PMID: 14719433 DOI: 10.1177/0310057x0303100614] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A 62-year-old man with a history of non-insulin-dependent diabetes mellitus, hypertension and obesity, presented for elective lumbar laminectomy for spinal canal stenosis. Twenty minutes after placement in the prone position, he developed left orbital proptosis. The surgery was deferred and a subsequent CT scan showed an orbital haemangioma. This case highlights the importance of meticulous attention to eye-care for patients in the prone position.
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Affiliation(s)
- R Greenberg
- Department of Anaesthesia and Pain Medicine, Alfred Hospital, Commercial Road, Melbourne, Vic. 3181
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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: 57] [Impact Index Per Article: 6.3] [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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Modrzejewska M, Grzesiak W, Zaborski D, Modrzejewska A. The role of lipid dysregulation and vascular risk factors in glaucomatous retrobulbar circulation. Bosn J Basic Med Sci 2015; 15:50-6. [PMID: 26042513 DOI: 10.17305/bjbms.2015.299] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Revised: 02/09/2015] [Accepted: 02/09/2015] [Indexed: 01/12/2023] Open
Abstract
The aim of this study was to evaluate selected lipid-related and vascular factors and their effect on retrobulbar hemodynamics in glaucoma. Fifty-six patients with primary open angle glaucoma (POAG) [POAG group; mean age 68.32 years (SD±0.21)] and 54 patients in control group [CG, mean age 68.1 years (SD±5.34)] were examined. Peak systolic velocity, end-diastolic velocity, mean velocity, pulsatility index, and resistive index of the ophthalmic artery, the central retinal artery and the posterior ciliary arteries were measured by Color Doppler Imaging. Selected lipid-related, systemic and local vascular parameters were evaluated. Statistical methods included Shapiro-Wilk, Student-t and Mann-Whitney U tests, and Spearman rank correlations. In POAG group systolic arterial blood pressure, diastolic arterial blood pressure, total cholesterol, low density lipoprotein cholesterol (LDL-ch), and intraocular pressure were significantly higher; while ocular perfusion pressure, high density lipoprotein cholesterol (HDL-ch) and diastolic ocular perfusion pressure were significantly lower (p≤0.05). Color Doppler Imaging confirmed blood flow abnormalities in all investigated arteries. In addition, significant correlations of HDL-ch, LDL-ch and triglycerides (TG) with peak systolic velocity, end-diastolic velocity and mean velocity were found in individual arteries (p≤0.05). Also, significant associations of systolic arterial blood pressure, ocular perfusion pressure, systolic oclular perfusion pressure and diastolic ocular perfusion pressure with peak systolic velocity, end-diastolic velocity, mean velocity and resistive index were revealed in the posterior ciliary arteries (p≤0.05). Dysregulation of lipid-related and vascular factors, as well as statistical correlation between the above and retrobulbar blood flow indices, might imply their role in vasoconstrictive processes during glaucomatous endotheliopathy.
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Lim JKH, Nguyen CTO, He Z, Vingrys AJ, Bui BV. The effect of ageing on ocular blood flow, oxygen tension and retinal function during and after intraocular pressure elevation. PLoS One 2014; 9:e98393. [PMID: 24866182 PMCID: PMC4035318 DOI: 10.1371/journal.pone.0098393] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 05/02/2014] [Indexed: 12/14/2022] Open
Abstract
PURPOSE To investigate the effect of ageing on the recovery of ocular blood flow, intravitreal oxygen tension and retinal function during and after intraocular pressure (IOP) elevation. METHODS Long Evans rats (3- and 14-month-old) underwent acute stepwise IOP elevation from 10 to 120 mmHg (5 mmHg steps each 3 minutes). IOP was then returned to baseline and recovery was monitored for 2 hours. Photopic electroretinograms (ERG) were recorded at each IOP step during stress and at each minute during recovery. Ocular blood flow and vitreal oxygen tension (pO2) were assayed continuously and simultaneously using a combined laser Doppler flow meter (LDF) and an oxygen sensitive fibre-optic probe, respectively. The combined sensor was placed in the vitreous chamber, proximal to the retina. Data were binned into 3 minute intervals during stress and 1 min intervals during recovery. Recovery data was described using a bi-logistic function. RESULTS Rats of both ages showed similar susceptibility to IOP elevation, with pO2 showing a closer relationship to ERG than LDF. During recovery, both ages showed a distinctive two-phased recovery for all three measures with the exception of the LDF in 3-month-old rats, which showed only 1 phase. In all animals, LDF recovered fastest (<1 minute), followed by pO2 (<10 minute) and ERG (>1 hour). 14-month-old rats showed surprisingly faster and greater LDF recovery compared to the younger group, with similar levels of pO2 recovery. However, the ERG in these middle-aged animals did not fully recover after two hours, despite showing no difference in susceptibility to IOP during stress compared to the young group. CONCLUSIONS Young and middle-aged eyes showed similar susceptibility to IOP elevation in terms of pO2, LDF and ERG. Despite this lack of difference during stress, older eyes did not completely recover function, suggesting a more subtle age-related susceptibility to IOP.
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Affiliation(s)
- Jeremiah K. H. Lim
- Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia
| | - Christine T. O. Nguyen
- Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia
| | - Zheng He
- Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia
| | - Algis J. Vingrys
- Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia
| | - Bang V. Bui
- Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia
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Retinal ganglion cells: Energetics, compartmentation, axonal transport, cytoskeletons and vulnerability. Prog Retin Eye Res 2013; 36:217-46. [PMID: 23891817 DOI: 10.1016/j.preteyeres.2013.07.001] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 07/02/2013] [Accepted: 07/02/2013] [Indexed: 11/20/2022]
Abstract
Retinal ganglion cells (RGCs) are specialized projection neurons that relay an immense amount of visual information from the retina to the brain. RGC signal inputs are collected by dendrites and output is distributed from the cell body via very thin (0.5-1 μm) and long (∼50 mm) axons. The RGC cell body is larger than other retinal neurons, but is still only a very small fraction (one ten thousandths) of the length and total surface area of the axon. The total distance traversed by RGCs extends from the retina, starting from synapses with bipolar and amacrine cells, to the brain, to synapses with neurons in the lateral geniculate nucleus. This review will focus on the energy demands of RGCs and the relevant tissues that surround them. RGC survival and function unexceptionally depends upon free energy, predominantly adenosine triphosphate (ATP). RGC energy metabolism is vastly different when compared to that of the photoreceptors. Each subcellular component of the RGC is remarkably different in terms of structure, function and extracellular environment. The energy demands and distribution of each component are also distinct as evidenced by the uneven distribution of mitochondria and ATP within the RGC - signifying the presence of intracellular energy gradients. In this review we will describe RGCs as having four subcellular components, (1) Dendrites, (2) Cell body, (3) Non-myelinated axon, including intraocular and optic nerve head portions, and (4) Myelinated axon, including the intra-orbital and intracranial portions. We will also describe how RGCs integrate information from each subcellular component in order achieve intracellular homeostatic stability as well as respond to perturbations in the extracellular environment. The possible cellular mechanisms such as axonal transport and axonal cytoskeleton proteins that are involved in maintaining RGC energy homeostasis during normal and disease conditions will also be discussed in depth. The emphasis of this review will be on energetic mechanisms within RGC components that have the most relevance to clinical ophthalmology.
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Abstract
Perioperative visual loss (POVL), a rare, but devastating complication, can follow non-ocular surgery. Highest rates of visual loss are with cardiac and spine surgery. The main causes of visual loss after non-ocular surgery are retinal vascular occlusion and ischaemic optic neuropathy. This review updates readers on the incidence, suspected risk factors, diagnosis, and treatment of POVL due to these conditions.
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Affiliation(s)
- S Roth
- Department of Anaesthesia and Critical Care, University of Chicago, 5841 South Maryland Avenue, Box MC 4028, Chicago, IL 60637, USA.
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12
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Ehrlich R, Kheradiya NS, Winston DM, Moore DB, Wirostko B, Harris A. Age-related ocular vascular changes. Graefes Arch Clin Exp Ophthalmol 2008; 247:583-91. [DOI: 10.1007/s00417-008-1018-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Revised: 11/19/2008] [Accepted: 11/24/2008] [Indexed: 10/21/2022] Open
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Orzalesi N, Rossetti L, Omboni S. Vascular risk factors in glaucoma: the results of a national survey. Graefes Arch Clin Exp Ophthalmol 2006; 245:795-802. [PMID: 17120006 DOI: 10.1007/s00417-006-0457-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Revised: 09/12/2006] [Accepted: 09/12/2006] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND The role of vascular risk factors in glaucoma is still being debated. To assess the importance of vascular risk factors in patients with primary open-angle glaucoma (POAG), data from the medical history of 2,879 POAG patients and 973 age-matched controls were collected and analyzed. METHODS DESIGN observational survey. SETTING 35 Italian academic centers. STUDY POPULATION POAG patients and age-matched controls. In order to reduce bias consecutive patients were included. OBSERVATION PROCEDURES data concerning vascular risk factors were collected for all patients with a detailed questionnaire. A complete ophthalmological examination with assessment of intraocular pressure (IOP), visual field, optic disc, and systemic blood pressure was performed. MAIN OUTCOME MEASURES the ESH-ESC (European Society of Hypertension-European Society of Cardiology) guidelines were used to calculate the level of cardiovascular risk. Crude and adjusted estimates of the odds ratios (OR) were calculated for all cardiovascular risk factors in POAG and controls. RESULTS The study included 2,879 POAG patients and 973 controls. POAG cases had a significantly higher systolic and diastolic blood pressure (p = 0.001) and systolic perfusion pressure (p = 0.02) as compared with controls. Also mean IOP was significantly higher in the POAG group (p = 0.01), while diastolic perfusion pressure was not significantly different in the two groups. Myopia was more prevalent in the POAG group (23 vs 18%, p = 0.005) as well as a positive family history for glaucoma (26 vs 12%, p = 0.004). POAG patients tended to have a higher cardiovascular risk than controls: 63% of glaucoma cases vs 55% of controls (OR: 1.38, p = 0.005) had a "high" or "very high" cardiovascular risk. CONCLUSIONS The level of cardiovascular risk was significantly higher in glaucoma patients than in controls.
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Affiliation(s)
- Nicola Orzalesi
- Department of Medicine, Surgery and Odontology, University of Milan, San Paolo Hospital, Milan, Italy.
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Hayreh SS. Erectile Dysfunction Drugs and Non-Arteritic Anterior Ischemic Optic Neuropathy: Is There a Cause and Effect Relationship? J Neuroophthalmol 2005; 25:295-8. [PMID: 16340497 DOI: 10.1097/01.wno.0000189059.90057.98] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The recent reports of non-arteritic anterior ischemic optic neuropathy (NAION) occurring shortly after ingestion of erectile dysfunction agents have raised the question of whether these agents have a cause-and-effect relationship to NAION. The nature of optic nerve head blood flow and the various factors that influence it, the systemic vascular effects of these agents, and the clinical features of NAION lead me to believe that these agents are contributory factors. Patients with the appropriate risk factors should, therefore, be warned of this possibility and advised to refrain from using these agents.
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Affiliation(s)
- Sohan Singh Hayreh
- Department of Ophthalmology and Visual Sciences, College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA.
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Yücel I, Akar Y, Yücel G, Ciftçioğlu MA, Keleş N, Aslan M. Effect of hypercholesterolemia on inducible nitric oxide synthase expression in a rat model of elevated intraocular pressure. Vision Res 2005; 45:1107-14. [PMID: 15707919 DOI: 10.1016/j.visres.2004.11.018] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2004] [Revised: 10/05/2004] [Accepted: 11/01/2004] [Indexed: 11/16/2022]
Abstract
PURPOSE This study was performed to examine the effect of hypercholesterolemia on inducible nitric oxide synthase (NOS-2) expression and oxidative tissue injury in an experimental rat model of elevated IOP. METHODS Wistar rats were maintained on either regular chow or a high-cholesterol diet for 24 weeks. Intraocular pressure (IOP) was elevated in hypercholesterolemic rats by unilaterally cauterizing three episcleral vessels. Rats were divided into four experimental groups as follows; hypercholesterolemia, hypercholesterolemia+elevated IOP, elevated IOP and control. NOS-2 distribution, lipid peroxidation and retinal nerve fiber layer (RNFL) thickness was evaluated in all experimental groups at the end of 24 weeks. RESULTS Light microscopic evaluation of retinas in hypercholesterolemic rats revealed breaks and discontinuation in focal areas in the outer nuclear layer (ONL). NOS-2 positive staining was observed throughout the outer plexiform layer (OPL), inner plexiform layer (IPL) and ganglion cell layer (GCL) in rats with elevated IOP and/or hypercholesterolemia. Calculated values of RNFL thickness in hypercholesterolemic rats were significantly higher than those in the control and elevated IOP group. Vitreous malondialdehyde (MDA) levels detected in elevated IOP (3.51+/-0.31 nmol/mg protein) and hypercholesterolemia+elevated IOP (5.14+/-1.28 nmol/mg protein) groups were significantly higher than those detected in hypercholesterolemic (1.92+/-1.43 nmol/mg protein) and control (1.89+/-0.24 nmol/mg protein) groups. CONCLUSION The presented data confirms hypercholesterolemia as a risk factor in the development of glaucomatous optic neuropathy (GON) and suggests that increased circulating cholesterol may exacerbate disease progression by inducing NOS-2 expression and elevating oxidant tissue injury.
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Affiliation(s)
- Iclal Yücel
- Department of Ophthalmology, Akdeniz University Medical School, 07070 Antalya, Turkey
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Abstract
Posterior ischemic optic neuropathy (PION) is an uncommon cause of perioperative visual loss. Perioperative PION has been most frequently reported after spinal surgery and radical neck dissection. The visual loss typically presents immediately after recovery from anesthesia, although it may be delayed by several days. Visual loss is often bilateral and profound with count fingers vision or worse. The examination findings are consistent with an optic neuropathy; however the funduscopic examination is initially normal. The cause is unknown, although patient-specific susceptibility to perioperative hemodynamic derangements is likely. No treatment has proven to be effective. The prognosis for visual recovery is generally poor.
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Affiliation(s)
- Lawrence M Buono
- Neuro-Ophthalmology Service, Duke University Eye Center, Durham, North Carolina, USA
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17
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Kokaze A, Yoshida M, Ishikawa M, Matsunaga N, Makita R, Satoh M, Sekiguchi K, Masuda Y, Uchida Y, Takashima Y. Longevity-associated mitochondrial DNA 5178 A/C polymorphism is associated with intraocular pressure in Japanese men. Clin Exp Ophthalmol 2004; 32:131-6. [PMID: 15068427 DOI: 10.1111/j.1442-9071.2004.00796.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Mitochondrial DNA 5178 adenine/cytosine (mt5178 A/C) polymorphism has been reported to be associated with longevity in Japanese individuals, with experimental findings concluding that mt5178 A is an anti-atherogenic genotype. The aim of this study was to determine whether mt5178 A/C polymorphism influences intraocular pressure (IOP), and its relationship with the development of arteriosclerosis. METHODS Four hundred and forty-nine male volunteers who had visited a general hospital for medical check-up between August 1999 and August 2000 were enrolled. Of these, 386 Japanese men who had not undergone any medical treatment for hypertension, ocular hypertension or glaucoma were selected as subjects of this study. After these subjects were genotyped, a cross-sectional study regarding the relationship between genotype and IOP was conducted. RESULTS Mean IOP was significantly higher in men with mt5178 C (13.3 mmHg) than in those with mt5178 A (12.7 mmHg) (P = 0.037). This significant difference in mean IOP between the two genotypes remained evident after adjusting for age, body mass index, blood pressure, habitual smoking and habitual drinking. Interactions between mt5178 A/C polymorphism and habitual smoking or daily alcohol consumption with regard to IOP were observed. According to multiple regression analysis, habitual smoking was significantly associated with IOP in men with mt5178 A (P for trend = 0.020), while daily alcohol consumption was significantly associated with IOP in those with mt5178 C (P for trend = 0.021). CONCLUSION Longevity-associated mitochondrial DNA 5178 A/C polymorphism may be associated with IOP in Japanese men.
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Affiliation(s)
- Akatsuki Kokaze
- Department of Public Health, Kyorin University School of Medicine, Tokyo, Japan.
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Battaglia C, Mancini F, Regnani G, Persico N, Volpe A, De Aloysio D. Hormone therapy and ophthalmic artery blood flow changes in women with primary open-angle glaucoma. Menopause 2004; 11:69-77. [PMID: 14716185 DOI: 10.1097/01.gme.0000079741.18541.92] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To compare the effects of hormone therapy (HT) on plasma viscosity and Doppler flow parameters in normal, healthy, postmenopausal women and in women with normal-tension and chronic, open-angle glaucoma. DESIGN Eight postmenopausal women with glaucoma (group I) and 15 controls (group II) were given HT. The duration of the study was 6 months, and the women were examined in basal condition and at the end of the treatment. All women underwent ultrasonographic evaluation of pelvic organs and color Doppler analysis of uterine, internal carotid, and ophthalmic arteries. Also, plasma viscosity was assayed. RESULTS The ultrasonographic analysis showed that none of the women presented with irregular endometrial echoes, polyps, or intracavitary fluid. In addition, endometrial thickness never exceeded the normal range (5 mm). Plasma viscosity and Doppler parameters significantly improved during therapy. However, the ophthalmic artery mean improvements of pulsatility index (-43% v -28%; P = 0.001), peak systolic blood flow velocity (+35% v +24%; P = 0.026), and time-averaged maximum velocity (+44% v +32%; P = 0.031) were significantly more evident in the control group than in the glaucoma group. CONCLUSIONS Although, in people with glaucoma, vasospasm can increase the risk of visual loss by inducing a retrobulbar blood flow reduction, HT seems to beneficially affect the ocular vascularization.
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Affiliation(s)
- Cesare Battaglia
- III Department of Obstetrics and Gynecology, University of Bologna, Bologna, Italy.
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19
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Ozdamar A, Ocakoglu O. Optic Nerve Head Blood Flow Using Scanning Laser Doppler Flowmetry After Laser in situ Keratomileusis. J Refract Surg 2003; 19:433-7. [PMID: 12899474 DOI: 10.3928/1081-597x-20030701-09] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
PURPOSE To investigate ocular blood flow changes following laser in situ keratomileusis (LASIK) in myopic eyes. METHODS Seventeen eyes of ten myopic patients were included in the study. Mean age of the seven men and three women was 29.1+/-2.5 years. Mean spherical equivalent refraction was -7.70+/-2.52 D. LASIK was performed with the Hansatome microkeratome and Summit SVS Apex excimer laser. Optic nerve head blood flow was measured by using the Heidelberg Retinal Flowmeter preoperatively and postoperatively at 1 day, 1 week, and 1 month. Preoperative ocular blood flow data (blood flow, volume, velocity) were compared with postoperative data using variance analysis. Correlation analysis was performed for age of patients, suction time, and ocular blood flow data. RESULTS Mean suction time was 19+/-7 seconds. There was no significant correlation between suction time, age, and ocular blood flow. We found an increase in blood flow at the lamina cribrosa taken 1 day postoperatively (P=.04). Blood flow returned to preoperative values at the 1-week and 1-month measurements in the lamina cribrosa region. There was no significant change in ocular blood flow data in the neuroretinal rim except an increase in velocity at the lower nasal quadrant on postoperative day 1 (P=.03). CONCLUSIONS LASIK caused a temporary increase in blood flow at the lamina cribrosa region of the optical nerve head in healthy myopic eyes. The increase in blood flow may suggest a compensatory change for maintaining blood flow in the ocular nerve head following LASIK-induced ischemia.
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Affiliation(s)
- Akif Ozdamar
- Department of Ophthalmology, Cerrahpasa Medical School, Istanbul University, Istanbul, Turkey.
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20
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Osborne NN, Chidlow G, Wood J, Casson R. Some current ideas on the pathogenesis and the role of neuroprotection in glaucomatous optic neuropathy. Eur J Ophthalmol 2003; 13 Suppl 3:S19-26. [PMID: 12749673 DOI: 10.1177/112067210301303s04] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The primary features of glaucomatous optic neuropathy are characteristic changes in the optic nerve head, a decrease in number of surviving ganglion cells and a reduction in vision. It is now generally accepted that a number of factors, including elevated intraocular pressure, could lead to the changes seen in the optic nerve head and to obtain a pharmacological means to treat the causes will vary from patient to patient. In contrast, a cascade of events have been proposed to explain how the changes in the optic nerve head may lead to the slow and differential death of ganglion cells in the disease. It is also proposed that drugs (neuroprotectants) influencing this cascade of events can attenuate ganglion cell death and lead to the treatment of all glaucoma patients.
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Affiliation(s)
- N N Osborne
- Nuffield Laboratory of Ophthalmology, Oxford University, Oxford, UK.
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21
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Abstract
This chapter discusses the cases of postoperative blindness reported in the literature and the theories that attempt to explain the mechanisms involved. Although uncommon, alterations in vision and blindness after anesthesia for major surgical procedures, particularly cardiopulmonary bypass or spine surgery, are well documented, with an incidence varying between 0.05% and 1%. Accurate incidence data are unavailable because it is not known what percentages are reported. However, the large number of case reports over many years has provided some significant information. Although sustained compression of the eye is an important cause, postoperative visual loss may also occur, in an unrelated manner, because of ischemic optic neuropathy, central retinal artery or vein occlusion, or cortical blindness.
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Affiliation(s)
- E Lynne Williams
- Department of Anesthesiology, University of Pittsburgh, A1305 Scaife Hall, 3550 Terrace Street, Pittsburgh, PA 15261, USA.
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22
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Hafez AS, Bizzarro RLG, Rivard M, Lesk MR. Changes in optic nerve head blood flow after therapeutic intraocular pressure reduction in glaucoma patients and ocular hypertensives. Ophthalmology 2003; 110:201-10. [PMID: 12511367 DOI: 10.1016/s0161-6420(02)01716-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE To detect and quantify changes in optic nerve head (ONH) and peripapillary retinal blood flow by scanning laser Doppler flowmetry (SLDF) in open-angle glaucoma (OAG) and ocular hypertension (OHT) after therapeutic intraocular pressure (IOP) reduction. DESIGN Prospective, nonrandomized, self-controlled trial. PARTICIPANTS Twenty patients with OAG and 20 patients with OHT with clinical indications for therapeutic IOP reduction were prospectively enrolled. INTERVENTION IOP reduction was achieved by medical, laser, or surgical therapy. All patients had IOP reductions more than 20% and a minimum of 4 weeks follow-up. MAIN OUTCOME MEASURES Blood flow measurements were performed by SLDF analysis software (version 3.3) using Heidelberg Retina Flowmeter images. Statistical evaluations were performed on both groups using a two-tailed distribution paired t test. RESULTS Twenty patients with OAG had a mean IOP reduction of 37% after treatment. In these patients, mean (+/- standard deviation) rim blood flow increased by 67% (from 158 +/- 79 arbitrary units to 264 +/- 127 arbitrary units, P = 0.001), whereas mean temporal peripapillary retinal flow decreased by 7.4% (P = 0.24), and mean nasal peripapillary retinal flow increased by 0.3% (P = 0.96). Twenty OHT patients had a mean IOP reduction of 33% after treatment. In contrast to the OAG group, neither the mean rim blood flow (7.5% increase from 277 +/- 158 arbitrary units to 298 +/- 140 arbitrary units, P = 0.41) nor the mean temporal (P = 0.35) or nasal (P = 0.88) peripapillary retinal flow changed significantly. CONCLUSIONS For a similar percentage of IOP reduction, OAG patients had a statistically significant improvement of blood flow in the neuroretinal rim of the ONH, whereas OHT patients did not demonstrate such a change. Peripapillary retinal blood flow, expected to be affected less in glaucoma, remained stable in both groups. In addition to indicating a response to therapy in OAG patients, the reported changes in rim perfusion suggest that ONH autoregulation may be defective in OAG while intact in OHT.
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Affiliation(s)
- Ali S Hafez
- Department of Ophthalmology and Guy-Bernier Research Center, Maisonneuve-Rosemont Hospital, University of Montreal, Montreal, Quebec, Canada
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Flammer J, Orgül S, Costa VP, Orzalesi N, Krieglstein GK, Serra LM, Renard JP, Stefánsson E. The impact of ocular blood flow in glaucoma. Prog Retin Eye Res 2002; 21:359-93. [PMID: 12150988 DOI: 10.1016/s1350-9462(02)00008-3] [Citation(s) in RCA: 1115] [Impact Index Per Article: 50.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Two principal theories for the pathogenesis of glaucomatous optic neuropathy (GON) have been described--a mechanical and a vascular theory. Both have been defended by various research groups over the past 150 years. According to the mechanical theory, increased intraocular pressure (IOP) causes stretching of the laminar beams and damage to retinal ganglion cell axons. The vascular theory of glaucoma considers GON as a consequence of insufficient blood supply due to either increased IOP or other risk factors reducing ocular blood flow (OBF). A number of conditions such as congenital glaucoma, angle-closure glaucoma or secondary glaucomas clearly show that increased IOP is sufficient to lead to GON. However, a number of observations such as the existence of normal-tension glaucoma cannot be satisfactorily explained by a pressure theory alone. Indeed, the vast majority of published studies dealing with blood flow report a reduced ocular perfusion in glaucoma patients compared with normal subjects. The fact that the reduction of OBF often precedes the damage and blood flow can also be reduced in other parts of the body of glaucoma patients, indicate that the hemodynamic alterations may at least partially be primary. The major cause of this reduction is not atherosclerosis, but rather a vascular dysregulation, leading to both low perfusion pressure and insufficient autoregulation. This in turn may lead to unstable ocular perfusion and thereby to ischemia and reperfusion damage. This review discusses the potential role of OBF in glaucoma and how a disturbance of OBF could increase the optic nerve's sensitivity to IOP.
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Hayreh SS, Podhajsky PA, Zimmerman B. Ipsilateral recurrence of nonarteritic anterior ischemic optic neuropathy. Am J Ophthalmol 2001; 132:734-42. [PMID: 11704035 DOI: 10.1016/s0002-9394(01)01192-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
PURPOSE To report the prevalence of recurrence of nonarteritic anterior ischemic optic neuropathy (NA-AION) in the same eye and possible contributing risk factors. DESIGN Cohort study. METHODS SETTING Institutional. STUDY POPULATION The study includes 594 consecutive patients (829 eyes) with a diagnosis of NA-AION and follow-up of at least two months after the onset of NA-AION, examined in the Ocular Vascular Clinic since 1973. Simple progression of visual loss during an episode of NA-AION was not considered a fresh episode. INTERVENTION OR OBSERVATION PROCEDURES: Every patient had ophthalmic evaluation, including visual acuity, visual fields with a Goldmann perimeter, intraocular pressure, and slit lamp and ophthalmoscopic evaluation at initial visit and at each follow-up visit. The patients also had systemic evaluation; some patients had echocardiography (166 patients) and 24-hour ambulatory blood pressure (BP) monitoring-the latter was investigated in 80 patients (17 with and 63 without recurrence of NA-AION) who consented to participate in this study which was started in 1989. While optic disk edema was present, the patients were followed every 2 to 3 weeks. Once the optic disk edema resolved, they were followed up after 3 months, 6 months, and then at yearly intervals unless they had some new visual complaint. MAIN OUTCOME MEASURES Prevalence of a fresh episode of NA-AION in the same eye, and comparison of ocular and systemic risk factors between patients with and without recurrence of NA-AION in the same eye. RESULTS Of the 594 patients (829 eyes) in the study, recurrence of NA-AION in the same eye occurred in 45 patients (53 eyes) with a median follow-up of 3.1 years (range 2 months to 30.5 years) from the first onset of NA-AION. The Kaplan-Meier survival curve showed cumulative percentage of recurrence of NA-AION from first episode to second episode at three months 1.0%+/-0.4%(SE), at 6 months 2.7%+/-0.7%, at one year 4.1%+/-0.9%, and 2 years 5.8%+/-1.1%. There was no significant association between recurrence of NA-AION and the systemic conditions that were examined, except for nocturnal arterial hypotension. Overall patients with a recurrence of NA-AION had a significantly lower mean nighttime minimum diastolic BP (P =.003) and greater mean percentage drop during sleep in diastolic BP (P =.011) than those with no recurrence of NA-AION; all other measures of nocturnal hypotension were not significantly predictive. CONCLUSIONS Recurrence of NA-AION in the same eye is uncommon (6.4%). Our study indicates that nocturnal diastolic arterial hypotension may be a risk factor; however, since this is a multifactorial disease, other so far unknown risk factors may also play a role. The role of various risk factors which may contribute to the recurrence of NA-AION is discussed.
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Affiliation(s)
- S S Hayreh
- Department of Ophthalmology, College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA.
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25
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Abstract
Evidence has gradually emerged that there is vascular insufficiency in the optic nerve head (ONH) in both anterior ischemic optic neuropathy (AION) and glaucomatous optic neuropathy (GON); thus both represent ischemic disorders of the ONH. Together these diseases constitute a major cause of blindness or seriously impaired vision in man. Consequently there has recently been great interest in the ONH circulation in health and disease and in how to evaluate it. Many studies of the subject have been published, with conflicting interpretations and claims. The basis of the inconsistent information seems to be confusion on some fundamental issues concerning the ONH circulation itself. The objective of this paper is to differentiate myths and misconceptions from reality about the ONH blood supply; to elucidate the reasons for disagreement on the blood supply of the ONH; and to evaluate the reliability and validity of various methods currently used to measure ONH blood flow.
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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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26
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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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Harris A, Jonescu-Cuypers C, Martin B, Kagemann L, Zalish M, Garzozi HJ. Simultaneous management of blood flow and IOP in glaucoma. ACTA OPHTHALMOLOGICA SCANDINAVICA 2001; 79:336-41. [PMID: 11453850 DOI: 10.1034/j.1600-0420.2001.079004336.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Factors other than intraocular pressure (IOP) elevation must be involved in initiation and progression of glaucoma. An additional element in disease causation may be ischemia in the retina and optic nerve head. Ischemic damage to neurons in the CNS is similar mechanistically and histopathologically to changes seen in glaucoma. Further, glaucoma patients with normal IOP show clear evidence for cerebral and ocular ischemia. Aging and atherosclerosis reduce the ability of the eye to autoregulate blood flow when ocular perfusion pressure changes: the dependence of blood flow on perfusion pressure links ischemia to IOP. Consequently, neuroprotective treatments for glaucoma should be designed to both reduce IOP and improve ocular nutrient delivery.
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Affiliation(s)
- A Harris
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, IN 46202-5175, USA.
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28
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Kergoat H, Kergoat MJ, Justino L, Lovasik JV. Age-related topographical changes in the normal human optic nerve head measured by scanning laser tomography. Optom Vis Sci 2001; 78:431-5. [PMID: 11444633 DOI: 10.1097/00006324-200106000-00016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE This study was designed to investigate the effects of advanced aging on the optic nerve head (ONH) structure and retinal nerve fiber layer (RNFL) thickness in the eldest segment of our population. METHODS Twenty-seven healthy elderly subjects between 75 and 88 years of age (average, 80.1 +/- 0.83 years) and 30 healthy younger subjects between 20 and 32 years of age (average, 23.1 +/- 0.50 years) were recruited for a cross-sectional comparison between ONH morphology and RNFL thickness as measured by scanning laser tomography. The ONH disc, cup, and rim areas; cup-to-disc ratio; and the mean thickness of the RNFL were quantified. RESULTS The cup and disc areas as well as the cup-to-disc area ratio increased with age, whereas the RNFL thickness decreased during the course of normal senescence. CONCLUSIONS Any diagnoses of ocular pathology in the elderly must differentiate the effects of normal aging on the ONH topography and RNFL thickness. To that effect, the present study provides a clinical profile of ocular structures that extend into the oldest geriatric age group.
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Affiliation(s)
- H Kergoat
- School of Optometry, University of Montreal, Québec, Canada.
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29
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Kountouras J, Mylopoulos N, Boura P, Bessas C, Chatzopoulos D, Venizelos J, Zavos C. Relationship between Helicobacter pylori infection and glaucoma. Ophthalmology 2001; 108:599-604. [PMID: 11237916 DOI: 10.1016/s0161-6420(00)00598-4] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE To determine the frequency of Helicobacter pylori (H. pylori) infection in glaucoma patients and in anemic control participants. DESIGN Prospective, nonrandomized, comparative study. PARTICIPANTS The authors investigated 32 patients with chronic open-angle glaucoma (COAG), 9 patients with pseudoexfoliation glaucoma (PEG), and 30 age-matched anemic control participants. METHODS Upper gastrointestinal endoscopy was performed to evaluate macroscopic abnormalities, and gastric mucosal biopsy specimens were obtained for the presence of H. pylori infection tested by rapid urease slide test (CLO test) and by Cresyl fast violet staining, Giemsa staining, or both. The presence of gastritis was classified in accordance with the Sydney system by using hematoxylin and eosin stain. In addition, intestinal metaplasia was evaluated with Alcian blue stain. Saliva samples were also tested by CLO. Serum was analyzed for the presence of H. pylori-specific IgG antibodies by enzyme-linked immunosorbent assay. MAIN OUTCOME MEASURE Histologic examination for the presence of H. pylori. RESULTS In 87.5% of the COAG patients, 88.9% of the PEG patients, and 46.7% of the anemic control participants, H. pylori infection was histologically confirmed (odds ratio, 8.00; chi-square, 11.81; P = 0.0006 and 9.14; chi-square, 5.01; P = 0.02, respectively). H. pylori was detected by urease test: (1) in the gastric mucosa in 71.9% of the COAG patients, in 77.8% of the PEG patients, and in 46.7% of the anemic control participants (P = 0.03 and P > 0.05, respectively); and (2) in the saliva in 37.5% of the COAG patients, in 55.6% of the PEG patients, and in 30% of the anemic control participants (P > 0.05). Sixty-eight percent of glaucoma patients and 30% of anemic control participants were seropositive for H. pylori (P = 0.002). When compared with anemic control participants, glaucoma patients exhibited less often endoscopic normal appearance of gastric mucosa (P = 0.01), and more often antral gastritis (P = 0.0004) or peptic ulcer disease (P = 0.01). Histologic grade 3 gastritis was observed only in the glaucoma patients (P = 0.03). CONCLUSIONS H. pylori infection seems more frequent in glaucoma patients. If confirmed, this may indicate either a common factor that causes susceptibilities to both glaucoma and H. pylori infection or that H. pylori may be a causal factor for developing glaucoma.
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Affiliation(s)
- J Kountouras
- Department of Medicine, Second Medical Clinic, Aristotle University of Thessaloniki, Ippokration Hospital, Thessaloniki, Greece.
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30
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la Cour M, Kiilgaard JF, Eysteinsson T, Wiencke AK, Bang K, Dollerup J, Jensen PK, Stefánsson E. Optic nerve oxygen tension: effects of intraocular pressure and dorzolamide. Br J Ophthalmol 2000; 84:1045-9. [PMID: 10966963 PMCID: PMC1723627 DOI: 10.1136/bjo.84.9.1045] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIM To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide. METHODS Domestic pigs were used as experimental animals. Oxygen tension was measured by means of a polarographic electrode in the vitreous 0.5 mm anterior to the optic disc. This entity is called the optic nerve oxygen tension. Intraocular pressure was controlled by a hypodermic needle inserted into the anterior chamber and connected to a saline reservoir. RESULTS When the intraocular pressure was clamped at 20 cm H2O optic nerve oxygen tension was 20 (5) mm Hg (n=8). Intravenous administration of dorzolamide caused an increase in optic nerve oxygen tension of 43 (8)% (n=6). Both before and after administration of dorzolamide optic nerve oxygen tension was unaffected by changes in intraocular pressure, as long as this pressure remained below 60 cm H2O. At intraocular pressures of 60 cm H(2)O and below, dorzolamide significantly increased optic nerve oxygen tension. CONCLUSION Intravenous administration of 500 mg dorzolamide increases the oxygen tension at the optic nerve head during acute increases in intraocular pressure.
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Affiliation(s)
- M la Cour
- Eye Department, National University Hospital, University of Copenhagen, Denmark.
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Yaoeda K, Shirakashi M, Funaki S, Funaki H, Nakatsue T, Abe H. Measurement of microcirculation in the optic nerve head by laser speckle flowgraphy and scanning laser Doppler flowmetry. Am J Ophthalmol 2000; 129:734-9. [PMID: 10926981 DOI: 10.1016/s0002-9394(00)00382-2] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
PURPOSE To evaluate and compare blood flow measurements by laser speckle flowgraphy and scanning laser Doppler flowmetry in the optic nerve head of normal volunteers. METHODS This prospective study included 60 eyes of 60 normal volunteers (50.0 years; range, 21 to 77 years). Measurements were taken at the temporal neuroretinal rim away from visible vessels. The square blur rate, a quantitative index of relative blood velocity, was measured by laser speckle flowgraphy. Using scanning laser Doppler flowmetry, volume, flow, and velocity were measured at the same neuroretinal rim locations. RESULTS The average square blur rate, volume, flow, and velocity were 7.11 +/- 1.65, 7.74 +/- 3.19, 151.85 +/- 70.63, and 0.53 +/- 0. 23 arbitrary units, respectively (n = 60). Square blur rate correlated significantly with flow and velocity (r =.361, P =.005; r =.359, P =.005, respectively). However, there was no significant correlation between square blur rate and volume (r =.101, P =.441). Although square blur rate decreased significantly with increasing age (r = -.375, P =.003), volume, flow, or velocity showed no significant correlation with age (r = -.249, P =.054; r = -.166, P =. 205; r = -.143, P =.275, respectively). Square blur rate also decreased significantly with mean blood pressure (r = -.315, P =. 014), but volume, flow, or velocity showed no significant correlation with mean blood pressure (r = -.159, P =.225; r = -.059, P =.654; r = -.043, P =.742, respectively). CONCLUSION We found only a weak correlation between the blood flow indexes, as measured by laser speckle flowgraphy and scanning laser Doppler flowmetry because of basic differences in the principles of measurement.
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Affiliation(s)
- K Yaoeda
- Department of Ophthalmology, Niigata University School of Medicine, Niigata, Japan.
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Spaeth GL, Marques Pereira ML. How does resetting intraocular pressure help optic nerve function? Eye (Lond) 2000; 14 ( Pt 3B):476-87. [PMID: 11026977 DOI: 10.1038/eye.2000.134] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- G L Spaeth
- William and Anna Goldberg Glaucoma Service & Research Laboratories, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
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Abstract
There is clinical and experimental evidence that both increased intraocular pressure and disturbed circulation are involved in the pathogenesis of glaucomatous damage. Among the many factors discussed, decreased blood pressure and vasospasm are the most important, and these factors may, at least in part, be therapeutically influenced. The basic underlying disorder might be a vascular dysfunction leading to local vasospasm and to systemic hypotension.
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Affiliation(s)
- P Gasser
- Clinic of Medicine, Regionalspital, Lachen SZ, Switzerland
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Chung HS, Harris A, Evans DW, Kagemann L, Garzozi HJ, Martin B. Vascular aspects in the pathophysiology of glaucomatous optic neuropathy. Surv Ophthalmol 1999; 43 Suppl 1:S43-50. [PMID: 10416746 DOI: 10.1016/s0039-6257(99)00050-8] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Glaucoma remains a major eye illness with unknown etiology. Although elevated intraocular pressure is clearly a major risk factor, vascular deficits may contribute to initiation and progression of glaucoma. When intraocular pressure is acutely elevated in healthy individuals, the resistance index (derived from the peak systolic and end-diastolic velocities and an indirect index of vascular resistance distal to the site of measurement) in the central retinal and posterior ciliary arteries increases progressively. This result implies that mechanical and vascular factors may be coupled in such a way that perfusion of the retina and optic nerve head may be influenced by changes in the intraocular pressure. Further, at night, when ophthalmic artery flow velocities fall as arterial blood pressure falls in glaucoma patients, the risk of disease progression may be increased. The constancy of these same flow velocities in age-matched healthy individuals points to a possible vascular autoregulatory defect in glaucoma. In addition, in normal-tension glaucoma, vasodilation (CO2 inhalation) normalizes retrobulbar arterial flow velocities, hinting that some vascular deficits in glaucoma may be reversible. Finally, Ca2+ channel blockade improves contrast sensitivity in patients with normal-tension glaucoma, who also show increased retrobulbar vessel flow velocities, a result suggesting that visual function loss may be linked to ocular ischemia. Emerging evidence points to a role of ischemia in the pathogenesis of glaucoma, suggesting that treatments designed to improve ocular blood flow may benefit glaucoma patients.
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Affiliation(s)
- H S Chung
- Glaucoma Research and Diagnostic Center, Department of Ophthalmology, Indiana University, Indianapolis, USA
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35
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Groh MJ, Michelson G, Langhans MJ, Harazny J. Influence of age on retinal and optic nerve head blood circulation. Ophthalmology 1996; 103:529-34. [PMID: 8600432 DOI: 10.1016/s0161-6420(96)30662-3] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
PURPOSE To quantify the influence of age on the retinal perfusion, the authors investigated the microcirculation of the retina and optic nerve head (ONH) and the blood flow velocity in the central retinal artery (CRA). METHOD The authors examined two groups of healthy volunteers. In group 1 (n=36 eyes of 36 subjects; mean age, 41.5 +/- 14.9 years), retinal and ONH microcirculation was analyzed by scanning laser Doppler flowmetry. In group 2 (n=49 eyes from 49 subjects; mean age, 44.4 +/- 15.4 years), CRA blood flow velocity was examined using pulsed Doppler sonography. RESULTS Blood flow velocity of the CRA showed a negative correlation to age (systolic velocity, r= -0.47, P=0.001; diastolic velocity r= -0.49, P=0.001). The slope of the linear regression was -0.62 cm/second per 10 years for systolic blood velocity and -0.51 cm/second for diastolic blood velocity. Resistivity index (RI) (RI=[systolic velocity--diastolic velocity]/systolic velocity) as a marker of the rigidity of the vessel increased significantly with age (r=0.40, P=0.004). The slope was 0.03 per 10 years. Retinal microcirculation (flow omega-ret) decreased significantly with age (r= -0.63, P=0.00001). The slope was -34.9[AU] per 10 years. Optic nerve head blood flow showed no significant correlation to age (r= -0.30, P=0.071). CONCLUSION The authors' data indicate that there is a significant decrease of retinal and CRA blood flow of approximately 6% to 11% per decade. Optic nerve head blood flow seems not to be influenced by age.
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Affiliation(s)
- M J Groh
- Ophthalmology and Eye Hospital, University Erlangen-Nuernberg, Germany
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36
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Williams EL, Hart WM, Tempelhoff R. Optic Nerve Injury. Anesth Analg 1996. [DOI: 10.1213/00000539-199602000-00064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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37
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38
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Roth S, Roizen M. Optic nerve injury: role of the anesthesiologist? Anesth Analg 1996; 82:435-6. [PMID: 8561371 DOI: 10.1097/00000539-199602000-00063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Optic Nerve Injury. Anesth Analg 1996. [DOI: 10.1097/00000539-199602000-00064] [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]
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40
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Affiliation(s)
- S S Hayreh
- Department of Ophthalmology, University of Iowa, Iowa City, IA 52242-1091, USA
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41
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Abstract
This is a brief overview of multifaceted anatomical, experimental and clinical studies conducted by the author since 1955 on the optic nerve head circulation in health and disease. Conclusions, based on the accumulated information provided by these studies, are summarized. The studies on the pattern of blood supply of the optic nerve head have shown that: (a) its main source of blood supply is the posterior ciliary artery circulation, with retinal circulation supplying only the surface nerve fiber layer, (b) there is marked interindividual variation in the blood supply pattern, and (c) the blood supply in the optic nerve head has a sectorial distribution. The various factors which produce interindividual variation in the blood supply of the optic nerve head are discussed, particularly those in the posterior ciliary artery circulation; this is because all available evidence indicates that it is derangement in the posterior ciliary circulation in the optic nerve head that is primarily responsible for the common ischemic disorders of the optic nerve head, e.g. anterior ischemic optic neuropathy and glaucomatous optic neuropathy. Factors that may derange the blood flow in the optic nerve head include defective autoregulation of blood flow in it, vascular changes in its feeding arteries, hematologic abnormalities, systemic arterial hypertension and hypotension, and intraocular pressure; their roles are discussed. For better understanding and management of optic nerve head ischemic disorders, there is an urgent need for an accurate clinical method of assessment of blood flow in the posterior ciliary circulation in optic nerve head, since no satisfactory method is currently available. Redness or pallor of the optic disk on ophthalmoscopy is not a true guide to the optic nerve head vascularity as it gives no information about the state of the posterior ciliary circulation. Fluorescein fundus angiography, though far superior to the optic disk color for evaluation of optic nerve head vascularity, has a number of limitations. All these topics and various controversies about them are discussed briefly.
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Affiliation(s)
- S S Hayreh
- Department of Ophthalmology, University of Iowa, Iowa City 52242-1091, USA
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