Trabeculoplastia selectiva con láser en glaucoma primario de ángulo cerrado Use of selective laser trabeculoplasty in primary closed angle glaucoma

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Ailen Garcés Fernández

2010-06-01

Full Text Available OBJETIVOS: Determinar eficacia y seguridad de la trabeculoplastia selectiva láser en pacientes portadores de glaucoma primario de ángulo cerrado, operados de cataratas y/o glaucoma, e identificar la frecuencia de los principales efectos adversos. MÉTODOS: Investigación observacional descriptiva prospectiva en 35 pacientes (50 ojos portadores de glaucoma primario de ángulo cerrado sometidos a cirugía de cataratas y/o glaucoma, en el Instituto Cubano Oftalmológico "Ramón Pando Ferrer" entre mayo y noviembre de 2007. Se utilizó equipo Tango LT 5106-T, de Laserex. RESULTADOS: Predominaron pacientes femeninas, mayores de 60 años y piel no blanca, hipermétropes, elevada frecuencia de enfermedades crónicas no transmisibles. Se logró un 41,2 % de reducción de la presión intraocular a los 6 meses. La técnica en pacientes con antecedentes de cirugía filtrante previa mostró resultados muy similares a los no intervenidos. La terapia mostró efectividad en 88 % de los ojos, se logró disminuir la terapia médica hipotensora. Eventos adversos: picos tensionales, epiteliopatía corneal y dispersión de pigmentos. CONCLUSIONES: La técnica láser resultó ser eficaz para lograr control tensional y/o reducción de terapia médica antihipertensiva ocular en este tipo de pacientes.OBJECTIVES: To determine the efficiency and safety of selective laser trabeculoplasty in patients who suffered primary close angle glaucoma and were operated from cataract and/or glaucoma, and to identify the frequency of the main adverse effects. METHODS: Prospective descriptive and observational research study of 35 patients (50 eyes carrying primary close angle glaucoma, who were operated on from cataract and/or glaucoma at "Ramón Pando Ferrer" Cuban Institute of Ophthalmology from May to November 2007. The equipment called Tango LT 5106-T from Laserex was used. RESULTS: Female patients, people over 60 years-old, Caucausians, hypermetropics, high frequency of non

Optical coherence tomography, scanning laser polarimetry and confocal scanning laser ophthalmoscopy in retinal nerve fiber layer measurements of glaucoma patients.

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Fanihagh, Farsad; Kremmer, Stephan; Anastassiou, Gerasimos; Schallenberg, Maurice

2015-01-01

To determine the correlations and strength of association between different imaging systems in analyzing the retinal nerve fiber layer (RNFL) of glaucoma patients: optical coherence tomography (OCT), scanning laser polarimetry (SLP) and confocal scanning laser ophthalmoscopy (CSLO). 114 eyes of patients with moderate open angle glaucoma underwent spectral domain OCT (Topcon SD-OCT 2000 and Zeiss Cirrus HD-OCT), SLP (GDx VCC and GDx Pro) and CSLO (Heidelberg Retina Tomograph, HRT 3). Correlation coefficients were calculated between the structural parameters yielded by these examinations. The quantitative relationship between the measured RNFL thickness globally and for the four regions (superior, inferior, nasal, temporal) were evaluated with different regression models for all used imaging systems. The strongest correlation of RNFL measurements was found between devices using the same technology like GDx VCC and GDx Pro as well as Topcon OCT and Cirrus OCT. In glaucoma patients, the strongest associations (R²) were found between RNFL measurements of the two optical coherence tomography devices Topcon OCT and Cirrus OCT (R² = 0.513) and between GDx VCC and GDx Pro (R² = 0.451). The results of the OCTs and GDX Pro also had a strong quantitative relationship (Topcon OCT R² = 0.339 and Cirrus OCT R² = 0.347). GDx VCC and the OCTs showed a mild to moderate association (Topcon OCT R² = 0.207 and Cirrus OCT R² = 0.258). The confocal scanning laser ophthalmoscopy (HRT 3) had the lowest association to all other devices (Topcon OCT R² = 0.254, Cirrus OCT R² = 0.158, GDx Pro R² = 0.086 and GDx VCC R² = 0.1). The measurements of the RNFL in glaucoma patients reveal a high correlation of OCT and GDx devices because OCTs can measure all major retinal layers and SLP can detect nerve fibers allowing a comparison between the results of this devices. However, CSLO by means of HRT topography can only measure height values of the retinal surface but it cannot distinguish

Laser in Glaucoma and Ocular Hypertension (LiGHT) trial. A multicentre, randomised controlled trial: design and methodology.

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Gazzard, Gus; Konstantakopoulou, Evgenia; Garway-Heath, David; Barton, Keith; Wormald, Richard; Morris, Stephen; Hunter, Rachael; Rubin, Gary; Buszewicz, Marta; Ambler, Gareth; Bunce, Catey

2018-05-01

The Laser in Glaucoma and Ocular Hypertension (LiGHT) Trial aims to establish whether initial treatment with selective laser trabeculoplasty (SLT) is superior to initial treatment with topical medication for primary open-angle glaucoma (POAG) or ocular hypertension (OHT). The LiGHT Trial is a prospective, unmasked, multicentre, pragmatic, randomised controlled trial. 718 previously untreated patients with POAG or OHT were recruited at six collaborating centres in the UK between 2012 and 2014. The trial comprises two treatment arms: initial SLT followed by conventional medical therapy as required, and medical therapy without laser therapy. Randomisation was provided online by a web-based randomisation service. Participants will be monitored for 3 years, according to routine clinical practice. The target intraocular pressure (IOP) was set at baseline according to an algorithm, based on disease severity and lifetime risk of loss of vision at recruitment, and subsequently adjusted on the basis of IOP control, optic disc and visual field. The primary outcome measure is health-related quality of life (HRQL) (EQ-5D five-level). Secondary outcomes are treatment pathway cost and cost-effectiveness, Glaucoma Utility Index, Glaucoma Symptom Scale, Glaucoma Quality of Life, objective measures of pathway effectiveness, visual function and safety profiles and concordance. A single main analysis will be performed at the end of the trial on an intention-to-treat basis. The LiGHT Trial is a multicentre, pragmatic, randomised clinical trial that will provide valuable data on the relative HRQL, clinical effectiveness and cost-effectiveness of SLT and topical IOP-lowering medication. ISRCTN32038223, Pre-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The Management of Secondary Glaucoma in Nanophthalmic Patients

Institute of Scientific and Technical Information of China (English)

Shengsong Huang; Minbin Yu; Changyu Qiu; Tiancai Ye

2002-01-01

Purpose: To investigate the clinical characteristcs, management of secondary glaucoma in nanophthalmos, and the prevention of its complications.Methods: Retrospectively, 9 cases (17 eyes) with nanophthalmic glaucoma were studied.Results: The axial length of the eyes ranged (14.36 ～ 19.33) mm; All of the cases combined with hyperopia ranged (+7.00～+16.00)D. All 17 eyes had the manifestation like angle-closure glaucoma.The glaucoma was controlled in 9 of 17 eyes at the early stage, which underwent laser iridotomy (4 of 9 eyes also underwent laser iridoplasty). 1 eye underwent ciliary photocoagulation because its visual acuity was lost and the patient complained of pain. The other 7 eyes underwent filtration surgery and 3 of them had permanent loss of vision caused by disastrous complications after the surgery.Conclusions: Management of secondary glaucoma in nanophthalmos is complicated. The laser iris surgery is safe and effective in glaucoma at the early stage. Vortex vein decompression, sclerotectomy or anterior sclerotomy may be performed to reduce disastrous complications.

Ahmed glaucoma valve in uveitic patients with fluocinolone acetonide implant-induced glaucoma: 3-year follow-up

Directory of Open Access Journals (Sweden)

Kubaisi B

2018-05-01

Full Text Available Buraa Kubaisi,1,2 Arash Maleki,1,2 Aseef Ahmed,1,2 Neel Lamba,1,2 Haitham Sahawneh,1,2 Andrew Stephenson,1,2 Alyssa Montieth,1,2 Shobha Topgi,3 C Stephen Foster1,2,4 1Massachusetts Eye Research and Surgery Institution, Waltham, MA, USA; 2Ocular Immunology & Uveitis Foundation, Waltham, MA, USA; 3The State University of New York Downstate, Brooklyn, NY, USA; 4Harvard Medical School, Boston, MA, USA Purpose: To evaluate the efficacy and safety of Ahmed glaucoma valve (AGV in eyes with noninfectious uveitis that had fluocinolone acetonide intravitreal implant (Retisert™-induced glaucoma. Methods: This retrospective study reviewed the safety and efficacy of AGV implantation in patients with persistently elevated intraocular pressure (IOP after implantation of a fluocinolone acetonide intravitreal implant at the Massachusetts Eye Research and Surgery Institution between August 2006 and November 2015. Results: Nine patients with 10 uveitic eyes were included in this study, none of which had preexisting glaucoma in the study eye. Mean patient age was 42 years; 6 patients were female and 3 were male. Baseline mean IOP was 30.6 mmHg prior to AGV placement while mean IOP-lowering medications were 2.9. In the treatment groups, there was a statistically significant reduction in post-AGV IOP. IOP was lowest at 1-week after AGV implantation (9.0 mmHg. Nine out of 10 eyes achieved an IOP below target value of 22 mmHg and/or a 20% reduction in IOP from baseline 1 month and 1 year following AGV placement. All other postoperative time points showed all 10 eyes reaching this goal. A statistically significant decrease in IOP-lowering medication was seen at the 1-week, 1-month, and 3-year time points compared to baseline, while a statistically significant increase was seen at the 3-month, 6-month, and 2-year post-AGV time points. No significant change in retinal nerve thickness or visual field analysis was found. Conclusion: AGV is an effective and safe method of

Port-wine vascular malformations and glaucoma risk in Sturge-Weber syndrome.

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Sharan, Sapna; Swamy, Brighu; Taranath, Deepa Ajay; Jamieson, Robyn; Yu, Tao; Wargon, Orli; Grigg, John R

2009-08-01

Treatment of the capillary vascular malformation (port-wine stain) in Sturge-Weber syndrome with the use of a laser is helpful cosmetically. However, concerns have been raised that laser obliteration of port-wine stains may result in ocular hypertension. The aim of this study was to review clinical features and management of ocular complications of SWS and assess the effects of dermatological laser treatment on the incidence of glaucoma or ocular hypertension. This retrospective cohort study was conducted in an institutional setting. All patients had involvement of the face. Patients who underwent skin laser to the port-wine vascular malformation were analyzed further. Ocular involvement, glaucoma, and skin laser treatment and the relationship to ocular hypertension/glaucoma were observed. Forty-one Sturge-Weber syndrome patients with port-wine vascular malformation were analyzed. Glaucoma was observed in 24 patients (58.5%) at mean age of 2.9 years (range, 0.0-16.5). Of these, 18 (75.0%) were treated with medical therapy, and 10 (41.7%) required trabeculectomy, with 2 of these requiring Seton implant. Of the 41 patients, 28 (68.3%) underwent laser to face/forehead. Mean age of laser commencement was 5 years (range, 0.4-16.5). Thirteen did not undergo laser treatment. Fourteen of the 28 and 10 of the 13 developed ocular hypertension/glaucoma. This retrospective review did not find evidence to suggest that laser treatment of port-wine vascular malformations causes glaucoma or that it can worsen a preexisting ocular hypertension or glaucoma. Statistical analysis was inconclusive.

The Philadelphia Glaucoma Detection and Treatment Project

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Waisbourd, Michael; Pruzan, Noelle L.; Johnson, Deiana; Ugorets, Angela; Crews, John E.; Saaddine, Jinan B.; Henderer, Jeffery D.; Hark, Lisa A.; Katz, L. Jay

2016-01-01

Purpose To evaluate the detection rates of glaucoma-related diagnoses and the initial treatments received in the Philadelphia Glaucoma Detection and Treatment Project, a community-based initiative aimed at improving the detection, treatment, and follow-up care of individuals at risk for glaucoma. Design Retrospective analysis. Participants A total of 1649 individuals at risk for glaucoma who were examined and treated in 43 community centers located in underserved communities of Philadelphia. Methods Individuals were enrolled if they were African American aged ≥50 years, were any other adult aged ≥60 years, or had a family history of glaucoma. After attending an informational glaucoma workshop, participants underwent a targeted glaucoma examination including an ocular, medical, and family history; visual acuity testing, intraocular pressure (IOP) measurement, and corneal pachymetry; slit-lamp and optic nerve examination; automated visual field testing; and fundus color photography. If indicated, treatments included selective laser trabeculoplasty (SLT), laser peripheral iridotomy (LPI), or IOP-lowering medications. Follow-up examinations were scheduled at the community sites after 4 to 6 weeks or 4 to 6 months, depending on the clinical scenario. Main Outcome Measures Detection rates of glaucoma-related diagnoses and types of treatments administered. Results Of the 1649 individuals enrolled, 645 (39.1%) received a glaucoma-related diagnosis; 20.0% (n = 330) were identified as open-angle glaucoma (OAG) suspects, 9.2% (n = 151) were identified as having narrow angles (or as a primary angle closure/suspect), and 10.0% (n = 164) were diagnosed with glaucoma, including 9.0% (n = 148) with OAG and 1.0% (n = 16) with angle-closure glaucoma. Overall, 39.0% (n = 64 of 164) of those diagnosed with glaucoma were unaware of their diagnosis. A total of 196 patients (11.9%) received glaucoma-related treatment, including 84 (5.1%) who underwent LPI, 13 (0.8%) who underwent SLT

Glaucoma associated with the management of rhegmatogenous retinal detachment

Directory of Open Access Journals (Sweden)

Mangouritsas G

2013-04-01

Full Text Available George Mangouritsas, Spyridon Mourtzoukos, Dimitra M Portaliou, Vassilios I Georgopoulos, Anastasia Dimopoulou, Elias Feretis Eye Clinic, General Hospital "Hellenic Red Cross", Athens, Greece Abstract: Transient or permanent elevation of intraocular pressure (IOP is a common complication following vitreoretinal surgery. Usually secondary glaucoma, which develops after scleral buckling procedures, or pars plana vitrectomy for repair of rhegmatogenous retinal detachment, is of multifactorial origin. It is essential, for appropriate management, to detect the cause of outflow obstruction. An exacerbation of preexisting open-angle glaucoma or a steroid-induced elevation of IOP should also be considered. Scleral buckling may be complicated by congestion and anterior rotation of the ciliary body resulting in secondary angle closure, which can usually resolve with medical therapy. The use of intravitreal gases may also induce secondary angle-closure with or without pupillary block. Aspiration of a quantity of the intraocular gas may be indicated. Secondary glaucoma can also develop after intravitreal injection of silicone oil due to pupillary block, inflammation, synechial angle closure, or migration of emulsified silicone oil in the anterior chamber and obstruction of the aqueous outflow pathway. In most eyes medical therapy is successful in controlling IOP; however, silicone oil removal with or without concurrent glaucoma surgery may also be required. Diode laser transscleral cyclophotocoagulation and glaucoma drainage devices constitute useful treatment modalities for long-term IOP control. Cooperation between vitreoretinal and glaucoma specialists is necessary to achieve successful management. Keywords: retinal detachment, intraocular pressure elevation, glaucoma, vitrectomy, intravitreal gas, silicone oil

Update on pigment dispersion syndrome and pigmentary glaucoma.

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Okafor, Kingsley; Vinod, Kateki; Gedde, Steven J

2017-03-01

The present article reviews the clinical features and pathogenesis of pigment dispersion syndrome and pigmentary glaucoma and provides an update regarding their diagnosis and management. Newer imaging modalities including ultrasound biomicroscopy and anterior segment optical coherence tomography facilitate visualization of the iris concavity characteristic of eyes with pigment dispersion syndrome and pigmentary glaucoma. Patients with pigmentary glaucoma may be distinguished from those with other glaucoma types by the presence of typical symptoms, personality type, and patterns of diurnal intraocular pressure fluctuation. Although laser iridotomy has been shown to alter iris anatomy in pigmentary glaucoma, it is not proven to slow visual field progression. Multiple trials have validated the safety and efficacy of filtering surgery in treating pigmentary glaucoma, with fewer studies published on the role of micro-invasive glaucoma surgery. Literature from the review period has further defined the unique clinical characteristics of pigment dispersion syndrome and pigmentary glaucoma. Laser surgery has a limited role in the management of these entities, whereas trabeculectomy remains an acceptable first-line surgical treatment. Further studies are needed to define the potential application of the newer micro-invasive glaucoma procedures in pigmentary glaucoma.

Maximizing cost-effectiveness by adjusting treatment strategy according to glaucoma severity

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Guedes, Ricardo Augusto Paletta; Guedes, Vanessa Maria Paletta; Gomes, Carlos Eduardo de Mello; Chaoubah, Alfredo

2016-01-01

Abstract Background: The aim of this study is to determine the most cost-effective strategy for the treatment of primary open-angle glaucoma (POAG) in Brazil, from the payer's perspective (Brazilian Public Health System) in the setting of the Glaucoma Referral Centers. Methods: Study design was a cost-effectiveness analysis of different treatment strategies for POAG. We developed 3 Markov models (one for each glaucoma stage: early, moderate and advanced), using a hypothetical cohort of POAG patients, from the perspective of the Brazilian Public Health System (SUS) and a horizon of the average life expectancy of the Brazilian population. Different strategies were tested according to disease severity. For early glaucoma, we compared observation, laser and medications. For moderate glaucoma, medications, laser and surgery. For advanced glaucoma, medications and surgery. Main outcome measures were ICER (incremental cost-effectiveness ratio), medical direct costs and QALY (quality-adjusted life year). Results: In early glaucoma, both laser and medical treatment were cost-effective (ICERs of initial laser and initial medical treatment over observation only, were R$ 2,811.39/QALY and R$ 3,450.47/QALY). Compared to observation strategy, the two alternatives have provided significant gains in quality of life. In moderate glaucoma population, medical treatment presented the highest costs among treatment strategies. Both laser and surgery were highly cost-effective in this group. For advanced glaucoma, both tested strategies were cost-effective. Starting age had a great impact on results in all studied groups. Initiating glaucoma therapy using laser or surgery were more cost-effective, the younger the patient. Conclusion: All tested treatment strategies for glaucoma provided real gains in quality of life and were cost-effective. However, according to the disease severity, not all strategies provided the same cost-effectiveness profile. Based on our findings, there should be a

The Laser in Glaucoma and Ocular Hypertension (LiGHT) trial. A multicentre randomised controlled trial: baseline patient characteristics.

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Konstantakopoulou, Evgenia; Gazzard, Gus; Vickerstaff, Victoria; Jiang, Yuzhen; Nathwani, Neil; Hunter, Rachael; Ambler, Gareth; Bunce, Catey

2018-05-01

The laser in glaucoma and ocular hypertension (LiGHT) trial aims to establish whether initial treatment with selective laser trabeculoplasty (SLT) is superior to initial treatment with topical medication for primary open angle glaucoma (POAG) or ocular hypertension (OHT). LiGHT is a prospective unmasked, multicentre, pragmatic, randomised controlled trial (RCT). 718 previously untreated patients with POAG or OHT were recruited at 6 UK centres between 2012 and 2014. Patients were randomised to initial SLT followed by medical therapy or medical therapy without laser. Participants will be monitored for 3 years, according to routine clinical practice. The primary outcome is EQ-5D-5L. Secondary outcomes are treatment pathway cost and cost-effectiveness, Glaucoma Utility Index (GUI), Glaucoma Symptom Scale, Glaucoma Quality of Life (GQL), pathway effectiveness, visual function, safety and concordance. A total of 555 patients had POAG and 163 OHT; 518 patients had both eyes eligible. The mean age for patients with POAG was 64 years and for OHT 58 years. 70% of all participants were white. Median IOP for OHT eyes was 26 mm Hg and 23 mm Hg for POAG eyes. Median baseline visual field mean deviation was -0.81 dB for OHT eyes and -2.82 dB for POAG eyes. There was no difference between patients with POAG and patients with OHT on the EQ-5D-5DL; the difference between OHT and POAG on the GUI was -0.02 and 1.23 on the GQL. The LiGHT trial is the first RCT to compare the two treatment options in a real-world setting. The baseline characteristics of the LiGHT cohort compare well with other landmark glaucoma studies. ISRCTN32038223, Pre-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Glaucoma treatment trends: a review.

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Conlon, Ronan; Saheb, Hady; Ahmed, Iqbal Ike K

2017-02-01

Glaucoma is one of the most common causes of blindness worldwide, and its prevalence is increasing. The aim of the present review is to describe the current medical and surgical treatment trends in the management of open-angle glaucoma. There has been an increase in the availability of glaucoma medications and the use of laser trabeculoplasty over the past decade, with a subsequent decrease in invasive incisional surgery. In addition, a new class of glaucoma procedures, termed microinvasive glaucoma surgery, has emerged, which aims to fill the gap between conservative medical management and more invasive surgery. Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

Trabeculoperforation? Trabeculoretraction? Trabeculoplasty? Review of the various designations used for laser treatment in primary open-angle glaucoma.

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Moulin, F; Haut, J; Abboud, E

1985-01-01

A historical recall and an attempt to simplify the numerous terms used to designate laser treatments for primary open-angle glaucoma (POAG) are presented. There are two main types of laser treatment for POAG involving two entirely different procedures. The first one, contemporary with the beginning of laser photocoagulation, imitates the action of the scalpel, namely goniotomy ab interno or trabeculotomy ab externo. The goal of this early procedure was to produce a through and through trabecular hole but instead of the cutting edge of the knife, it uses the explosive effect of the laser. This procedure has been given numerous names. Among the most frequent ones, we find: 'laser trabeculopuncture', 'laseropuncture', 'goniopuncture', 'laser trabeculectomy', 'laser trabeculotomy', 'laser trabeculopexy'. We prefer to gather them under an explicit generic term: 'laser trabeculoperforation'. The results of this procedure have been very disappointing until now, particularly with conventional lasers, e.g. continuous-wave argon laser, owing to the predominance of their thermal effect over their explosive effect and also to the great scarring property of the trabecular meshwork. In the second type of glaucoma laser treatment, instead of trying to make a patent hole in the trabecular meshwork, the surgeon seeks to reshape the inner trabecular surface by means of argon laser microscars in order to produce a reversal of the trabecular collapse, which is now considered to be one of the major etiologies of POAG.(ABSTRACT TRUNCATED AT 250 WORDS)

Ahmed glaucoma valve in uveitic patients with fluocinolone acetonide implant-induced glaucoma: 3-year follow-up.

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Kubaisi, Buraa; Maleki, Arash; Ahmed, Aseef; Lamba, Neel; Sahawneh, Haitham; Stephenson, Andrew; Montieth, Alyssa; Topgi, Shobha; Foster, C Stephen

2018-01-01

To evaluate the efficacy and safety of Ahmed glaucoma valve (AGV) in eyes with noninfectious uveitis that had fluocinolone acetonide intravitreal implant (Retisert™)-induced glaucoma. This retrospective study reviewed the safety and efficacy of AGV implantation in patients with persistently elevated intraocular pressure (IOP) after implantation of a fluocinolone acetonide intravitreal implant at the Massachusetts Eye Research and Surgery Institution between August 2006 and November 2015. Nine patients with 10 uveitic eyes were included in this study, none of which had preexisting glaucoma in the study eye. Mean patient age was 42 years; 6 patients were female and 3 were male. Baseline mean IOP was 30.6 mmHg prior to AGV placement while mean IOP-lowering medications were 2.9. In the treatment groups, there was a statistically significant reduction in post-AGV IOP. IOP was lowest at 1-week after AGV implantation (9.0 mmHg). Nine out of 10 eyes achieved an IOP below target value of 22 mmHg and/or a 20% reduction in IOP from baseline 1 month and 1 year following AGV placement. All other postoperative time points showed all 10 eyes reaching this goal. A statistically significant decrease in IOP-lowering medication was seen at the 1-week, 1-month, and 3-year time points compared to baseline, while a statistically significant increase was seen at the 3-month, 6-month, and 2-year post-AGV time points. No significant change in retinal nerve thickness or visual field analysis was found. AGV is an effective and safe method of treatment in fluocinolone acetonide intravitreal implant-induced glaucoma. High survival rate is expected for at least 3 years.

Effect of Topical Calcium Channel Blockers on Intraocular Pressure in Steroid-induced Glaucoma.

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Ganekal, Sunil; Dorairaj, Syril; Jhanji, Vishal; Kudlu, Krishnaprasad

2014-01-01

To evaluate the effect of 0.125% verapamil and 0.5% diltiazem eye drops on intraocular pressure (IOP) in steroid-induced glaucoma in rabbit eyes. A total of 18 rabbits with steroid-induced glaucoma were divided into three groups (A, B and C; n = 6 each). Right eyes in groups A, B and C received 0.5% diltiazem, 0.125% verapamil and 0.5% timolol eye drops twice daily for 12 days, respectively; whereas, left eyes received distilled water. IOP was measured with Tono-pen XL at baseline, day 4, day 8, and day 12 of treatment. Both 0.5% diltiazem and 0.125% verapamil eye drops significantly reduced IOP compared to control eyes (p cite this article: Ganekal S, Dorairaj S, Jhanji V, Kudlu K. Effect of Topical Calcium Channel Blockers on Intraocular Pressure in Steroid-induced Glaucoma. J Current Glau Prac 2014;8(1):15-19.

Improving Access to Eye Care among Persons at High-Risk of Glaucoma in Philadelphia--Design and Methodology: The Philadelphia Glaucoma Detection and Treatment Project.

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Hark, Lisa; Waisbourd, Michael; Myers, Jonathan S; Henderer, Jeffrey; Crews, John E; Saaddine, Jinan B; Molineaux, Jeanne; Johnson, Deiana; Sembhi, Harjeet; Stratford, Shayla; Suleiman, Ayman; Pizzi, Laura; Spaeth, George L; Katz, L Jay

2016-01-01

The Wills Eye Glaucoma Research Center initiated a 2-year demonstration project to develop and implement a community-based intervention to improve detection and management of glaucoma in Philadelphia. The glaucoma detection examination consisted of: ocular, medical, and family history; visual acuity testing; corneal pachymetry; biomicroscopy of the anterior segment; intraocular pressure (IOP) measurement; gonioscopy; funduscopy; automated visual field testing; and fundus-color photography. Treatment included laser surgery and/or IOP-lowering medication. A cost analysis was conducted to understand resource requirements. Outcome measures included; prevalence of glaucoma-related pathology and other eye diseases among high-risk populations; the impact of educational workshops on level of knowledge about glaucoma (assessed by pre- and post-test evaluation); and patient satisfaction of the glaucoma detection examinations in the community (assessed by satisfaction survey). Treatment outcome measures were change in IOP at 4-6 weeks and 4-6 months following selective laser trabeculoplasty treatment, deepening of the anterior chamber angle following laser-peripheral iridotomy treatment, and rate of adherence to recommended follow-up examinations. Cost outcomes included total program costs, cost per case of glaucoma detected, and cost per case of ocular disease detected. This project enrolled 1649 participants (African Americans aged 50+ years, adults 60+ years and individuals with a family history of glaucoma). A total of 1074 individuals attended a glaucoma educational workshop and 1508 scheduled glaucoma detection examination appointments in the community setting. The Philadelphia Glaucoma Detection and Treatment Project aimed to improve access and use of eye care and to provide a model for a targeted community-based glaucoma program.

Experimental microendoscopic photoablative laser goniotomy as a surgical model for the treatment of dysgenetic glaucoma.

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Jacobi, P C; Dietlein, T S; Krieglstein, G K

1996-11-01

The aim of this study was to investigate the feasibility of photoablative Er:YAG laser goniotomy under microendoscopic control in a surgical cloudy corneal model of primary infantile glaucoma. Pectinate ligaments of 12 freshly enucleated cadaver porcine eyes were treated by ab interno single-pulse (5 mJ, 200 microseconds) Er:YAG laser (2.94 microns) photoablation. Through a clear corneal incision near the limbus an ophthalmic microendoscope (18 and 20 gauge) was inserted into the anterior chamber. Internal structures were observed and photoablative laser goniotomy was conducted under video guidance. Following treatment all eyes were prepared for light and scanning electron microscopy. Anterior chamber angle structures and tissue photoablation were clearly visualized on the videoscreen using ophthalmic microendoscopy. Energy settings of 5 mJ per pulse proved to be sufficient for reproducible photoablation of pectinate ligaments, accompanied by the root of the iris falling back and exposing trabecular meshwork. This was confirmed histopathologically. Scatter thermal damage was less than 30 microns. This new therapeutic modality, which combines endoscopic visualization of the internal structures with photoablative laser goniotomy, can be effective in the management of dysgenetic glaucoma in the presence of a cloudy cornea. High reproducibility of contact laser photoablation enabled sufficient control of incision depth and was not accompanied by inadvertent tissue damage to adjacent intraocular structures.

Argon laser peripheral iridoplasty for angle-closure glaucoma in sibilings with weill-marchesani syndrome.

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Ritch, R; Solomon, L D

1992-01-01

A patient with Weill-Marchesani syndrome and angle-closure glaucoma had persistent appositional closure after laser iridotomy that was unrelieved by topical application of either miotic or cycloplegic agents. Argon laser peripheral iridoplasty successfully opened the angle. The patient's sister also had Weill-Marchesani syndrome and angle closure unrelieved by laser iridotomy. Angle closure in Weill-Marchesani syndrome and the response to laser iridotomy and treatment with either miotic or cycloplegic agents may be complex and depends on the relative proportion of pupillary block as a mechanism underlying the angle closure, the functional status of the zonular apparatus, and the degree of angle crowding by the peripheral iris in the presence or absence of peripheral anterior synechiae.

Ab interno laser sclerostomy in aphakic patients with glaucoma and chronic inflammation.

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Wilson, R P; Javitt, J C

1990-08-15

Five patients with aphakia, glaucoma, and chronic inflammation were treated with ab interno sclerostomy by using the continuous wave Nd:YAG laser focused through a sapphire probe. After a follow-up period of 24 to 28 months, three of five patients had good intraocular pressure control. The sclerostomy failed in one patient when it was occluded by vitreous. The second failure was attributed to closure of the sclerostomy because of chronic intraocular inflammation.

Argon laser trabeculoplasty as primary therapy in open angle glaucoma

International Nuclear Information System (INIS)

Mahar, P.S.; Jamali, K.K.

2008-01-01

To determine the effect of Argon Laser Trabeculoplasty (ALT) as a primary mode of therapy in reducing the intraocular Pressure (IOP) of patients diagnosed with Primary Open Angle Glaucoma (POAG). A total of 35 eyes of 35 patients with the gender distribution of 27 men and 8 women who were newly diagnosed with POAG, were included in this study. Mean age of the patients was 55.2 years with the range of 32 to 76 years. All of them were treated with argon laser trabeculoplasty as a primary mode of therapy. Intra ocular pressure was measured objectively using Goldman applanation tonometer, pre-and-post laser therapy. The pre-laser mean IOP was 27.63 mmHg (range 21-40 mmHg). The post-laser mean IOP measured at 6 months follow up was 15.5 mmHg (range 11 - 33 mmHg) with mean decrease of 12.1 mmHg. The decrease in IOP was seen in 32 eyes (95%) with no change observed in 3 (5%) eyes. The result shows a marked decline in IOP in patients with POAG who underwent ALT as a primary mode of treatment. Further studies with large sample size and longer follow-up will help in making future recommendations. (author)

Improving Access to Eye Care among Persons at High-Risk of Glaucoma in Philadelphia — Design and Methodology: The Philadelphia Glaucoma Detection and Treatment Project

Science.gov (United States)

Myers, Jonathan S.; Henderer, Jeffrey; Crews, John E.; Saaddine, Jinan B.; Molineaux, Jeanne; Johnson, Deiana; Sembhi, Harjeet; Stratford, Shayla; Suleiman, Ayman; Pizzi, Laura; Spaeth, George L.; Katz, L. Jay

2016-01-01

Purpose The Wills Eye Glaucoma Research Center initiated a 2-year demonstration project to develop and implement a community-based intervention to improve detection and management of glaucoma in Philadelphia. Methods The glaucoma detection examination consisted of: ocular, medical, and family history; visual acuity testing; corneal pachymetry; biomicroscopy of the anterior segment; intraocular pressure (IOP) measurement; gonioscopy; funduscopy; automated visual field testing; and fundus-color photography. Treatment included laser surgery and/or IOP-lowering medication. A cost analysis was conducted to understand resource requirements. Outcome measures included; prevalence of glaucoma-related pathology and other eye diseases among high-risk populations; the impact of educational workshops on level of knowledge about glaucoma (assessed by pre- and post-test evaluation); and patient satisfaction of the glaucoma detection examinations in the community (assessed by satisfaction survey). Treatment outcome measures were change in IOP at 4–6 weeks and 4–6 months following selective laser trabeculoplasty treatment, deepening of the anterior chamber angle following laser-peripheral iridotomy treatment, and rate of adherence to recommended follow-up examinations. Cost outcomes included total program costs, cost per case of glaucoma detected, and cost per case of ocular disease detected. Results This project enrolled 1649 participants (African Americans aged 50+ years, adults 60+ years and individuals with a family history of glaucoma). A total of 1074 individuals attended a glaucoma educational workshop and 1508 scheduled glaucoma detection examination appointments in the community setting. Conclusions The Philadelphia Glaucoma Detection and Treatment Project aimed to improve access and use of eye care and to provide a model for a targeted community-based glaucoma program. PMID:26950056

Peripheral iridotomy for pigmentary glaucoma

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Michelessi, Manuele; Lindsley, Kristina

2016-01-01

Background Glaucoma is a chronic optic neuropathy characterized by retinal ganglion cell death resulting in damage to the optic nerve head and the retinal nerve fiber layer. Pigment dispersion syndrome is characterized by a structural disturbance in the iris pigment epithelium (the densely pigmented posterior surface of the iris) that leads to dispersion of the pigment and its deposition on various structures within the eye. Pigmentary glaucoma is a specific form of open-angle glaucoma found in patients with pigment dispersion syndrome. Topcial medical therapy is usually the first-line treatment; however, peripheral laser iridotomy has been proposed as an alternate treatment. Peripheral laser iridotomy involves creating an opening in the iris tissue to allow drainage of fluid from the posterior chamber to the anterior chamber and vice versa. Equalizing the pressure within the eye may help to alleviate the friction that leads to pigment dispersion and prevent visual field deterioration. However, the effectiveness of peripheral laser iridotomy in reducing the development or progression of pigmentary glaucoma is unknown. Objectives The objective of this review was to assess the effects of peripheral laser iridotomy compared with other interventions, including medication, trabeculoplasty, and trabeculectomy, or no treatment, for pigment dispersion syndrome and pigmentary glaucoma. Search methods We searched a number of electronic databases including CENTRAL, MEDLINE and EMBASE and clinical trials websites such as (mRCT) and ClinicalTrials.gov. We last searched the electronic databases on 2 November 2015. Selection criteria We included randomized controlled trials (RCTs) that had compared peripheral laser iridotomy versus no treatment or other treatments for pigment dispersion syndrome and pigmentary glaucoma. Data collection and analysis We used standard methodological procedures for systematic reviews. Two review authors independently screened articles for eligibility

Novel surgical procedures in glaucoma: advances in penetrating glaucoma surgery.

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Filippopoulos, Theodoros; Rhee, Douglas J

2008-03-01

Despite late modifications and enhancements, traditional penetrating glaucoma surgery is not without complications and is reserved for patients in whom pharmacologic treatment and/or laser trabeculoplasty do not suffice to control the intraocular pressure. This article critically reviews recent advances in penetrating glaucoma surgery with particular attention paid to two novel surgical approaches: ab interno trabeculectomy with the Trabectome and implantation of the Ex-PRESS shunt. Ab interno trabeculectomy (Trabectome) achieves a sustained 30% reduction in intraocular pressure by focally ablating and cauterizing the trabecular meshwork/inner wall of Schlemm's canal. It has a remarkable safety profile with respect to early hypotonous or infectious complications as it does not generate a bleb, but it can be associated with early postoperative intraocular pressure spikes that may necessitate additional glaucoma surgery. The Ex-PRESS shunt is more commonly implanted under a partial thickness scleral flap, and appears to have similar efficacy to standard trabeculectomy offering some advantages with respect to the rate of early complications related to hypotony. Penetrating glaucoma surgery will continue to evolve. As prospective randomized clinical trials become available, we will determine the exact role of these surgical techniques in the glaucoma surgical armamentarium.

Management of exfoliative glaucoma: challenges and solutions.

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Holló, Gábor; Katsanos, Andreas; Konstas, Anastasios Gp

2015-01-01

Exfoliative glaucoma is the most common type of secondary open-angle glaucoma worldwide. It is characterized by high intraocular pressure (IOP) and worse 24-hour IOP characteristics. In order to minimize progression, treatment of exfoliative glaucoma has to provide a low long-term mean IOP and good 24-hour IOP control. To achieve these goals, fixed-dose combination eye drops, argon and selective laser trabeculoplasty, and various forms of surgery (trabeculectomy, deep sclerectomy, viscocanalostomy, ab interno trabeculotomy, trabecular aspiration, and cataract surgery) all need to be considered during the long-term management of the disease. Since exfoliative glaucoma is a disease of the elderly, and is frequently associated with systemic vascular disease, interdisciplinary consultations are of great clinical importance. These management aspects and the current medical, laser, and surgical results are covered in this review, with a special focus on the needs of the general ophthalmologist.

Management of glaucoma in pregnancy: risks or choices, a dilemma?

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Harinder Singh Sethi

2016-12-01

Full Text Available The treatment of glaucoma in and around pregnancy offers the unique challenge of balancing the risk of vision loss to the mother as against the potential harm to the fetus or newborn. Most anti-glaucoma drugs (i.e. beta-blockers, prostaglandin analogues, carbonic anhydrase inhibitors topical and systemic, cholinergics, anticholinesterases, and apraclonidine are considered category C agents and ophthalmologists are usually limited to treating patients with the category B drugs of brimonidine and dipivefrin. Brimonidine is generally the preferred first-line drug in the first, second and early third trimester. Late in the third trimester, brimonidine should be discontinued because it can induce central nervous system depression in newborns wherein topical carbonic anhydrase inhibitors may be the optimal choice. Glaucoma surgery can be performed with caution in second and third trimester if the patients have a strong indication for the procedure. However, anesthetics, sedative agents, and antimetabolites still have potential risk for the fetus. Argon laser trabeculoplasty (ALT or selective laser trabeculoplasty (SLT is an alternative treatment that can be performed in all trimesters. Carbonic anhydrase inhibitors and β-blockers are certified by the American Academy of Pediatrics for use during nursing. However, low doses of these medications should be considered when used in the breast feeding period. Optimum treatment for glaucoma in pregnancy must not be withheld so as to prevent any further deterioration in progressive vision loss and quality of life.

Laser trabeculotomy versus trabeculoplasty

International Nuclear Information System (INIS)

Ticho, U.; Frucht, J.

1984-01-01

Although laser trabeculotomy has failed in glaucoma management, the laser trabeculoplasty (LTP) procedure has proved to be helpful. LTP was found to improve glaucoma control in 80-90% of open angle glaucoma patients, and less in secondary glaucoma and low tension glaucoma (50%). The procedure is more successful in dark iris eyes and complications are transient. (Auth.)

Glaucoma after corneal replacement.

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Baltaziak, Monika; Chew, Hall F; Podbielski, Dominik W; Ahmed, Iqbal Ike K

Glaucoma is a well-known complication after corneal transplantation surgery. Traditional corneal transplantation surgery, specifically penetrating keratoplasty, has been slowly replaced by the advent of new corneal transplantation procedures: primarily lamellar keratoplasties. There has also been an emergence of keratoprosthesis implants for eyes that are high risk of failure with penetrating keratoplasty. Consequently, there are different rates of glaucoma, pathogenesis, and potential treatment in the form of medical, laser, or surgical therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

Diode laser trans - scleral cyclo - ablation as a primary surgical treatment for primary open - angle glaucoma after maximum tolerated medical therapy

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Mahmood, K.; Khan, M.T.; Butt, J.B.Y.

2011-01-01

The incidence rate and prevalence of glaucoma in Pakistan is similar to that of other dark - colored population countries. Primary trabeculectomy is still a preferred surgical approach. Diode laser is widely accepted as the therapy of choice in severe glaucoma cases. The purpose of this study was to deter-mine the role of Diode Laser Transscleral Cyclo-ablation as a primary surgical treatment option in Primary Open Angle Glaucoma after maximum tolerated medical therapy. This quasi - experimental study was con-ducted at Layton Rahmatullah Benevolent Trust Free Eye Care and Cancer Hospital, Lahore. Sixty patients fulfilling the inclusion criteria were selected from the Glaucoma unit for this study. 25 - 30 burns of Diode Laser were applied to 270 degrees avoiding 3 and 9 O clock positions, 1.5 mm posterior to the limbus. Laser was set at duration of 1 second and power between 1000 and 1500 mw. Patients were followed up for a period of one year. Results: Out of a total of 60 eyes with mean age 52.73 +- 7.40 years, 36 (60%) were male and 24 (40%) were female. The mean pre-operative Intra Ocular Pressure IOP was 41.0 +- 7.0 mmHg (The pre-operative IOP ranged from 28 mmHg to 60 mmHg). The mean post-operative IOP was 18.97 mmHg on day one, 16.75 mmHg at 1 week, 15.68 mmHg at 1 month, 15.00 mmHg at 6 months and by the end of a year it was about 14.15 mmHg (The post-operative IOP ranged from 6 mmHg to 52 mmHg). There was a significant drop of more than 50% of post-operative IOP as compared to pre-operative IOP. Conclusion: Diode Laser Transscleral Cycloablation is a practical, rapid, well - tolerated procedure that provides a significant lowering of intraocular pressure with few complications and can considered as alternative treatment in POAG if medical therapy fails. (author)

Transscleral Diode Laser Cyclophotocoagulation in Refractory Glaucoma

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Gülfidan Bitirgen

2012-12-01

Full Text Available Pur po se: To evaluate the safety and efficacy of transscleral diode laser cyclophotocoagulation (TSDLC in advanced glaucoma refractory to medical or surgical treatment. Ma te ri al and Met hod: The data of subjects who were treated with TSDLC between 2009 and 2011 were retrospectively reviewed. Intraocular pressure before and after treatment, visual acuity, the number of medications and complications were analysed. Success was defined as final IOP of 6-22 mmHg with or without antiglaucomatous medications. Re sults: Thirty seven eyes of 37 patients were included in the study. Mean age of patients and mean follow-up time were 61.73±17.13 years (range: 19-80 years and 8.06±5.81 months (range: 3-22 months, respectively. Mean pretreatment IOP was 38.68±8.94 mmHg and IOP was 26.46±11.34 mmHg (p <0.01 at the second week, whereas it was 24.97±10.84 mmHg (p<0.01 at the last visit. IOP of less than 22 mmHg was achieved in 40.5% of eyes at the last visit. Mean treatment number per eye was 1.48±0.73, and more than one treatment was required in 13 (35.1% eyes. Preoperative and postoperative mean total antiglaucomatous medications were 3.14±1.18 and 2.76±1.23, respectively. No phthisis bulbi or persistent hypotonia developed during the follow-up period. Dis cus si on: TSDLC is an effective and safe method for the treatment of refractory glaucoma. It also served to reduce the number of antiglaucoma medications, thus improving both the quality of life of the patients and their compliance to therapy. (Turk J Ophthalmol 2012; 42: 434-7

Effect of diode laser cyclophotocoagulation in treatment of patients with refractory glaucoma

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Čanadanović Vladimir

2015-01-01

Full Text Available Background/Aim. Refractory glaucoma is glaucoma resistant to conventional management (maximally tolerated medical therapy, one or more glaucoma surgeries and glaucoma in cases of neovascularisation after panretinal photocoagulation or cryoablation. The aim of the study was to determine the intraocular pressure (IOP lowering efficacy of transscleral diode laser cyclophotocoagulation (DCPC treatment in the management of pain and IOP in patients with refractory glaucoma. Methods. This nonrandomized, retrospective study, included 95 patients (95 eyes with refractory glaucoma treated at the University Eye Clinic, Clinical Center of Vojvodina, Novi Sad, Serbia, between November 2007 and November 2012 in accordance with the established protocols (16-18 spots, 270°, up to 5J of energy. All the eyes were treated with transscleral DCPC (Iris Medical OcuLight SLx, Iridex Co, Mountain View, USA. Patient's symptoms, bests corrected visual acuity and IOP were recorded 7 days, and 1, 3 and 6 months after the DCPC treatment. Results. Out of 95 patients (95 eyes enrolled in this study 24 (25.2% were with primary (the group I, and 71 (74.5% with secondary (the group II glaucoma. The mean baseline IOP in these two groups was similar: 36.08 ± 8.39 mmHg for the first group and 37.36 ± 8.19 mmHg in the second group. Measurement of the mean IOP in the group I showed the following results: on the day 7 it was 13.96 ± 8.30 mmHg (62.1% decrease of the baseline value, on the day 30 it was 18.44 ± 8.85 mmHg (48.9% decrease regarding the baseline value, after 3 months it was 22.44 ± 7.36 mmHg (37.8% decrease regarding the baseline value, and after 6 months it was 25.92 ± 7.65 mmHg (28.2% decrease regarding the baseline value. Measurement of IOP in the group II showed the following results: on the day 7 it was 15.77 ± 9.73 mmHg (57.8% decrease of the baseline value, on the day 30 it was 20.14 ± 10.20 mmHg (46.1% decrease regarding the baseline value, after 3 months

24-h Efficacy of Glaucoma Treatment Options.

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Konstas, Anastasios G P; Quaranta, Luciano; Bozkurt, Banu; Katsanos, Andreas; Garcia-Feijoo, Julian; Rossetti, Luca; Shaarawy, Tarek; Pfeiffer, Norbert; Miglior, Stefano

2016-04-01

Current management of glaucoma entails the medical, laser, or surgical reduction of intraocular pressure (IOP) to a predetermined level of target IOP, which is commensurate with either stability or delayed progression of visual loss. In the published literature, the hypothesis is often made that IOP control implies a single IOP measurement over time. Although the follow-up of glaucoma patients with single IOP measurements is quick and convenient, such measurements often do not adequately reflect the untreated IOP characteristics, or indeed the quality of treated IOP control during the 24-h cycle. Since glaucoma is a 24-h disease and the damaging effect of elevated IOP is continuous, it is logical that we should aim to understand the efficacy of all treatment options throughout the 24-h period. This article first reviews the concept and value of diurnal and 24-h IOP monitoring. It then critically evaluates selected available evidence on the 24-h efficacy of medical, laser and surgical therapy options. During the past decade several controlled trials have significantly enhanced our understanding on the 24-h efficacy of all glaucoma therapy options. Nevertheless, more long-term evidence is needed to better evaluate the 24-h efficacy of glaucoma therapy and the precise impact of IOP characteristics on glaucomatous progression and visual prognosis.

CLINICAL PRESENTATION OF LENS INDUCED GLAUCOMA: STUDY OF EPIDEMIOLOGY, DURATION OF SYMPTOMS, INTRAOCULAR PRESSURE AND VISUAL ACUITY

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Venkataratnam

2015-10-01

Full Text Available BACKGROUND: Lens Induced Glaucoma is a common cause of ocular morbidity. OBJECTIVES: Our study was to know the Epidemiological factors, Duration of Symptoms, Visual Acuity and Intraocular Pressure in the clinical Presentation of Lens Induced Glaucoma. MATERIALS AND METHODS : This w as a tertiary hospital based prospective study in the department of Glaucoma, Sarojini Devi Eye Hospital and Regional Institute of Ophthalmology (RIO, Osmania Medical College, Hyderabad over a period from March 2015 to August 2015. 50 Patients clinically diagnosed as Lens Induced Glaucoma (LIG were studied with the data of Age, Sex, literacy, Laterality and Rural / Urban status with the duration of symptoms, Intraocular pressure and Visual Acuity. The data was analyzed by simple statistical methods. RESULT S: 50 patients, clinically diagnosed as Lens Induced Glaucoma (LIG were studied. Age group distribution was 1(2.0% in 40 - 50yrs, 13 ( 26.0% in >50 - 60yrs, 26(52.0% in >60 - 70yrs and 10(20.0% in > 70 yrs. Sex distribution was 23(46.0% of Males and 27(54.0% of Females. Urban / Rural status was 15(30.0% of Urban and 35(70.0% of Rural. Literacy status was 7(14.0% of Literate and 43(86.0% of Illiterate. Laterality was RE in 24(48.0% and LE in 26(52.0%. Duration of the presenting symptoms before re porting to the Hospital was 12.0% in 2wks. Intraocular pressure (IOP in mm of Hg showed no case (0.0% in 20 – 40, 27(54.0% in >40 - 60 and 5(10.0% >60 wit h the Mean IOP of 42.12 mm of Hg. Visual Acuity (VA was PL +ve in 24(48.0 and HM - 3/60. CONCLUSIONS: Increasing age, female gender, rural, illiterate, and delayed reporting to the hospital after the pre senting symptoms were the common risk factors with increased Intraocular pressure and poor visual acuity in the clinical presentation of Lens induced Glaucoma.

YAG laser peripheral iridotomy for the prevention of pigment dispersion glaucoma a prospective, randomized, controlled trial.

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Scott, Andrew; Kotecha, Aachal; Bunce, Catey; Balidis, Miltos; Garway-Heath, David F; Miller, Michael H; Wormald, Richard

2011-03-01

To test the hypothesis that neodymium:yttrium-aluminum-garnet (Nd:YAG) laser peripheral iridotomy (LPI) significantly reduces the incidence of conversion from pigment dispersion syndrome (PDS) with ocular hypertension (OHT) to pigmentary glaucoma (PG). Prospective, randomized, controlled 3-year trial. One hundred sixteen eyes of 116 patients with PDS and OHT. Patients were assigned randomly either to Nd:YAG LPI or to a control group (no laser). The primary outcome measure was conversion to PG within 3 years, based on full-threshold visual field (VF) analysis using the Ocular Hypertension Treatment Study criteria. Secondary outcome measures were whether eyes required topical antiglaucoma medications during the study period and the time to conversion or medication. Fifty-seven patients were randomized to undergo laser treatment and 59 were randomized to no laser (controls). Age, gender, spherical equivalent refraction, and intraocular pressure at baseline were similar between groups. Outcome data were available for 105 (90%) of recruited subjects, 52 in the laser treatment group and 53 in the no laser treatment group. Patients were followed up for a median of 35.9 months (range, 10-36 months) in the laser arm and 35.9 months (range, 1-36 months) in the control arm. Eight eyes (15%) in the laser group and 3 eyes (6%) in the control group converted to glaucoma in the study period. The proportion of eyes started on medical treatment was similar in the 2 groups: 8 eyes (15%) in the laser group and 9 eyes (17%) in the control group. Survival analyses showed no evidence of any difference in time to VF progression or commencement of topical therapy between the 2 groups. Cataract extraction was performed on 1 patient in the laser group and in 1 patient in the control group during the study period (laser eye at 18 months; control eye at 34 months). This study suggests that there was no benefit of Nd:YAG LPI in preventing progression from PDS with OHT to PG within 3 years of

Challenges in the management of glaucoma in developing countries.

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Butt, Nadeem Hafeez; Ayub, Muhammad Hammad; Ali, Muhammad Hassaan

2016-01-01

Glaucoma is the most common optic neuropathy characterized by normal to raised intraocular pressure (IOP), visual field defects, loss of retinal nerve fiber layer, thinning of the neuroretinal rim, and cupping of the optic disc. IOP reduction by medical, laser, or surgical therapies remains the only clinically proven treatment of glaucoma. The challenges in glaucoma management are diverse. They include early detection and diagnosis, setting of appropriate target IOP, choice of treatment, monitoring of quality of life and sight, and compliance with the treatment. Early diagnosis can be made by assessing optic nerve structure using imaging devices and optic nerve function through perimetry. Reducing IOP and controlling its fluctuations are considered to be the most important factors in limiting progression of glaucoma. Selection of the best suitable therapy out of medical, surgical, or laser treatment options is yet another management challenge. Patients suffering from glaucoma experience poor quality of life owing to the diagnosis itself, functional visual loss, inconvenience and cost of treatment, and side effects of treatment. All these factors lead to poor compliance, adherence, and persistence to treatment, and further progression of the disease. It is, therefore, important that ophthalmologists keep all the aforementioned factors in mind when managing patients with glaucoma.

Cyclo-photocoagulation in the management of aphakic glaucoma

International Nuclear Information System (INIS)

Lee, P.-F.

1984-01-01

Transpupillary argon laser photocoagulation of the ciliary processes (TALC) through a widely dilated pupil, with or without cerebral depression, has been used in the management of glaucoma in aphakic eyes for a number of years. 58% of glaucoma in aphakics treated with TALC showed sustained and meaningful intraocular pressure reduction 2 months to 5 years after the procedure. Clinically, the TALC procedure is a relatively safe, effective, and an useful alternative approach in the management of selected cases of glaucoma in aphakics. (Auth.)

Analysis of Krypton Laser Combined With ND:YAG Laser in the Treatment of Angle Closure Glaucoma Effect%氪激光联合ND：YAG激光治疗闭角型青光眼效果分析

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张海涛; 刘岚; 王宇蕾

2015-01-01

青光眼位列全球不可逆致盲眼病第二位，致盲率高。我们用氪绿激光联合Nd：YAG激光，对原发性闭角型青光眼行周边虹膜成形术与周边虹膜切除术，采用超声生物显微镜（UBM）和房角镜对联合激光手术的有效性进行评价，结果证明联合激光治疗初次发作的急性闭角型青光眼安全、有效。%Glaucoma is a global irreversible blindness in the second rank, high rate of blindness. We use krypton green laser peripheral iris of primary angle closure glaucoma plasty. Combined Nd:YAG laser peripheral iris excision, the effectiveness of the combined laser surgery was evaluated by using the ultrasonic biological microscope (UBM) and the angle of the lens. The results show that the combined laser treatment of acute angle closure glaucoma is safe and effective.

Nanotechnology Applications for Glaucoma.

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Cetinel, Sibel; Montemagno, Carlo

2016-01-01

Glaucoma is the second leading cause of blindness worldwide, and the antiglaucoma treatments currently available suffer from various complications. Nanotechnology-based treatments show a great deal of promise in overcoming these complications and form the basis for next-generation glaucoma treatment strategies, with the help of applications such as controlled release, targeted delivery, increased bioavailability, diffusion limitations, and biocompatibility. Significant progress has been made in nanomedicine in the efficiency of antiglaucoma medications, nanofabrication systems such as microelectromechanical systems that remove the limitations of nanodevices, and tissue regeneration vesicles for developing glaucoma treatments not based on intraocular pressure. With the use of these advanced technologies, the prevention of glaucoma-induced blindness will be possible in the near future. Herein, we reviewed the recent advances in nanotechnology-based treatment strategies for glaucoma.

Primary angle closure glaucoma in a myopic kinship.

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Hagan, J C; Lederer, C M

1985-03-01

Three related myopic individuals with primary angle closure glaucoma are reported. They had true myopia and not pseudomyopia secondary to increased lenticular index of refraction. We believe one of these individuals (-8.62 spherical equivalent) to have the most myopic case of primary angle closure glaucoma reported in the literature. Although myopia is associated with anatomical factors that offer considerable protection from primary angle closure glaucoma, its presence does not eliminate the possibility of this disease. Laser iridectomy was effective in the treatment of these patients.

Pigment dispersion syndrome and pigmentary glaucoma--a major review.

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Niyadurupola, Nuwan; Broadway, David C

2008-12-01

Pigment dispersion syndrome (PDS) is an interesting condition that can lead to secondary open angle glaucoma. Pigmentary glaucoma is primarily a disease of young people, myopes and men. PDS is characterized by the presence of Krukenberg spindles, iris trans-illumination defects, trabecular meshwork pigmentation and backward bowing of the iris. Posterior bowing of the iris causes rubbing of the pigmented iris epithelium against lens structures, liberation of pigment and trabecular meshwork changes that result in reduced aqueous outflow with the risk of glaucoma. Peripheral laser iridotomy can reverse backward bowing of the iris and may prevent progression of pigmentary glaucoma.

Glaucoma and clinical characteristics in Vietnamese Americans.

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Peng, Pai-Huei; Manivanh, Richard; Nguyen, Ngoc; Weinreb, Robert N; Lin, Shan C

2011-08-01

To assess the proportions of glaucoma types and clinical characteristics in Vietnamese Americans in a single-center, retrospective study. Medical charts of Vietnamese-American patients who visited a single private practice in Northern California from 1998-2007 were reviewed. The main outcome measures included the distribution and characteristics of glaucoma types, and clinical parameters associated with the presence of various glaucomas. Data from 2247 patients aged 18-98 years were reviewed. Glaucoma was determined for 305 patients (13.6%). Among this group, 54.8% had primary open-angle glaucoma (POAG), 26.9% had primary angle-closure glaucoma (PACG), 13.4% had mixed mechanism glaucoma (MMG), and 4.9% had secondary glaucoma. In the MMG group (41 patients), 27 patients who initially had open angles developed narrow angles and underwent laser peripheral iridotomy (LPI) with a mean follow up of 6.4 years from the time of iridotomy. The other 13 patients had glaucoma progression with open angles after LPI. One POAG patient had neovascular glaucoma due to retinal vein occlusion several years later. Compared to the PACG group, the MMG group had significantly lower baseline intraocular pressure (25.0 vs. 20.2 mmHg, p = 0.007) but with no difference in biometry. POAG is the major type of glaucoma in this clinic-based Vietnamese population. However, Vietnamese appear to have a relatively higher proportion of PACG than Caucasians and those of African descent. It is recommended that gonioscopy be part of the regular eye check-up for adult Vietnamese patients.

Comparative study of the retinal nerve fibre layer thickness performed with optical coherence tomography and GDx scanning laser polarimetry in patients with primary open-angle glaucoma.

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Wasyluk, Jaromir T; Jankowska-Lech, Irmina; Terelak-Borys, Barbara; Grabska-Liberek, Iwona

2012-03-01

We compared the parameters of retinal nerve fibre layer in patients with advanced glaucoma with the use of different OCT (Optical Coherence Tomograph) devices in relation to analogical measurements performed with GDx VCC (Nerve Fiber Analyzer with Variable Corneal Compensation) scanning laser polarimetry. Study subjects had advanced primary open-angle glaucoma, previously treated conservatively, diagnosed and confirmed by additional examinations (visual field, ophthalmoscopy of optic nerve, gonioscopy), A total of 10 patients were enrolled (9 women and 1 man), aged 18-70 years of age. Nineteen eyes with advanced glaucomatous neuropathy were examined. 1) Performing a threshold perimetry Octopus, G2 strategy and ophthalmoscopy of optic nerve to confirm the presence of advanced primary open-angle glaucoma; 2) performing a GDx VCC scanning laser polarimetry of retinal nerve fibre layer; 3) measuring the retinal nerve fibre layer thickness with 3 different optical coherence tomographs. The parameters of the retinal nerve fibre layer thickness are highly correlated between the GDx and OCT Stratus and 3D OCT-1000 devices in mean retinal nerve fibre layer thickness, retinal nerve fibre layer thickness in the upper sector, and correlation of NFI (GDx) with mean retinal nerve fibre layer thickness in OCT examinations. Absolute values of the retinal nerve fibre layer thickness (measured in µm) differ significantly between GDx and all OCT devices. Examination with OCT devices is a sensitive diagnostic method of glaucoma, with good correlation with the results of GDx scanning laser polarimetry of the patients.

Structure-Function Correlation Using Confocal Laser Ophthalmoscope in Primary Open-Angle Glaucoma and Pseudoexfoliative Glaucoma.

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Pappas, Theofanis; Founti, Panayiota; Yin, Xiang Jun; Koskosas, Archimidis; Anastasopoulos, Eleftherios; Salonikiou, Angeliki; Kilintzis, Vasilios; Antoniadis, Antonios; Ziakas, Nikolaos; Topouzis, Fotis

2016-04-01

To compare Heidelberg Retina Tomograph (HRT) optic disc parameters and structure-function correlation between primary open-angle glaucoma (POAG) and pseudoexfoliative glaucoma (PEXG). Prospective, observation case series. A total of 54 POAG and 33 PEXG cases, consecutively recruited from a University Glaucoma Service, underwent a comprehensive ophthalmic examination, including HRT optic disc imaging. Glaucoma definition required the presence of both structural and functional damage. One eye per subject was included in the analysis. T test, Mann-Whitney U test, and analysis of covariance were used to compare HRT parameters between POAG and PEXG, adjusting for age, mean deviation (MD) in the visual field, intraocular pressure, and disc area. The correlation between HRT and MD was assessed in each group. Cup area (P=0.048), height variation contour (P=0.016), and cup/disc area ratio (P=0.023) were higher in POAG, whereas the mean retinal nerve fiber layer thickness (P=0.048), retinal nerve fiber layer cross-section area (P=0.044), and rim area (P=0.048) were lower in POAG, compared with PEXG. The correlation of HRT parameters with MD was significant only in the POAG group. At a similar level of functional damage, POAG subjects presented with more pronounced structural damage than PEXG subjects. The correlation between HRT and visual field parameters was more evident in POAG, compared with PEXG.

Heidelberg Retina Tomograph for the Detection of Glaucoma

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Barbara Cvenkel

2012-06-01

Full Text Available Heidelberg Retina Tomograph (HRT is a confocal scanning laser ophthalmoscope which acquires and analyzes 3-dimensional images of the optic nerve head. The latest instrument HRT3 includes software with larger ethinic-specific normative database. This review summarizes relevant published literature on HRT in diagnosing glaucoma, detecting glaucoma progression, the diagnostic accuracy of HRT among other imaging devices and its role in clinical practice.

Systems of imaging digital systems in case of glaucoma

International Nuclear Information System (INIS)

Fernandez Argones, Liamet; Piloto Diaz, Ibrain; Coba Penna, Maria Josefa; Perez Tamayo, Bertila; Dominguez Randulfe, Marerneda; Trujillo Fonseca, Katia

2009-01-01

Now a day we can't consider the strict follow up in Glaucoma without the use of the digital analysis of image system of the optic nerve head and the retinal nerve fiber layer. This is a review about some contributions of Scanning Laser Polarimetry (GDx VCC, Carl Zeiss Meditec, Dublin, CA), Confocal Scanning Laser (Heidelberg Retina Tomograph HRT, Heidelberg Engineering Inc.) and Optical Coherence Tomography (Stratus OCT, Carl Zeiss Meditec, Alemania) in the diagnosis and follow up of Glaucoma. It's considered that objective measurement giving by them must be incorporate in the rigorous analysis of each glaucomatous patient

Pattern of intraocular pressure reduction following laser trabeculoplasty in open-angle glaucoma patients: comparison between selective and nonselective treatment

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Almeida Jr ED

2011-07-01

Full Text Available Eglailson Dantas Almeida Júnior1, Luciano Moreira Pinto1,2, Rodrigo Antonio Brant Fernandes1,2, Tiago Santos Prata1,31Department of Ophthalmology, Federal University of São Paulo, São Paulo, Brazil; 2Cerpo Oftalmologia, São Paulo, Brazil; 3Hospital Medicina dos Olhos, São Paulo, BrazilObjective: To compare the pattern of intraocular pressure (IOP reduction following selective laser trabeculoplasty (SLT versus argon laser trabeculoplasty (ALT in open-angle glaucoma (OAG patients, and to investigate the ability of initial IOP reduction to predict mid-term success.Methods: A prospective, nonrandomized, interventional case series was carried out. Consecutive uncontrolled OAG glaucoma patients underwent SLT or ALT; the same preoperative medical regimen was maintained during follow-up. Data collected included age, type of OAG, pre- and postoperative IOP, number of glaucoma medications, and surgical complications. Post-treatment assessments were scheduled at day 1 and 7 and months 1, 3, and 6.Results: A total of 45 patients (45 eyes were enrolled [SLT group (n = 25; ALT group (n = 20]. Groups were similar for age, baseline IOP, and number of glaucoma medications (P ≥ 0.12. We found no significant differences in mean IOP reduction between SLT (5.1 ± 2.5 mmHg; 26.6% and ALT (4.4 ± 2.8 mmHg; 22.8% groups at month 6 (P = 0.38. Success rates (IOP ≤ 16 mmHg and IOP reduction ≥25% at last follow-up visit were similar for SLT (72% and ALT (65% groups (P = 0.36. Comparing the pattern of IOP reduction (% of IOP reduction at each visit between groups, we found a greater effect following SLT compared with ALT at day 7 (23.7% ± 13.7% vs 8.1% ± 9.5%; P < 0.001. No significant differences were observed at other time points (P ≥ 0.32. Additionally, the percentage of IOP reduction at day 7 and at month 6 were significantly correlated in the SLT group (R2 = 0.36; P < 0.01, but not in the ALT group (P = 0.89. Early postoperative success predicted late

Avaliação dos tipos de glaucoma no serviço de oftalmologia da UNICAMP Evaluation of glaucoma types at the sector of ophthalmology - UNICAMP

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Andréia Peltier Urbano

2003-01-01

Full Text Available OBJETIVO: Avaliar a freqüência dos tipos de glaucoma no Setor de Glaucoma do Hospital das Clínicas da Universidade Estadual de Campinas. MÉTODOS: Estudo transversal de 329 pacientes atendidos no Setor de Glaucoma da Universidade Estadual de Campinas entre 1 de outubro e 20 de dezembro de 2000, com avaliação dos tipos de glaucoma e conduta terapêutica. RESULTADOS: De 329 pacientes atendidos no Ambulatório de Glaucoma, 132 foram encaminhados ao ambulatório por suspeita de glaucoma (40,1% e 197 como glaucoma diagnosticado (59,9%. Dos 132 suspeitos de glaucoma, 90 (68,2% foram confirmados como tendo glaucoma e 42 (31,8% encontram-se em acompanhamento. Dos 329 pacientes avaliados, 283 (86% tinham glaucoma, 42 (12,8% suspeita de glaucoma, 2 (0,6% diagnóstico de glaucoma excluído e 2 (0,6% hipertensão ocular. Dos 530 olhos glaucomatosos, havia 298 (56,2% glaucomas primários de ângulo aberto, 108 (20,4% glaucomas primários de ângulo estreito, 21 (4% glaucomas pós-facectomia, 19 (3,6% glaucomas congênitos e 16 (3% glaucomas de pressão normal. A conduta terapêutica adotada foi inicialmente clínica em todos os casos. Após seguimento médio de 10,5 meses, 89 (16,8% olhos necessitaram tratamento com laser: 72 (13,6% iridotomias, 7 (1,3% trabeculoplastias e 10 (1,9% panfotocoagulações. Cento e setenta e cinco olhos (33% foram submetidos a tratamento cirúrgico. CONCLUSÃO: O tipo mais freqüente de glaucoma observado foi o glaucoma primário de ângulo aberto, seguido por glaucoma primário de ângulo estreito. Glaucomas como o de pressão normal e o pseudo-exfoliativo foram pouco freqüentes na população estudada.PURPOSE: To evaluate the frequency of different types of glaucoma at the Hospital das Clínicas of Campinas State University. METHODS: Cross-sectional study of 329 patients followed at the Glaucoma Service of Campinas State University from October 1 to December 20, 2000. The frequency of each type of glaucoma and the

Management of intermittent angle closure glaucoma with Nd: yag laser iridotomy as a primary procedure

International Nuclear Information System (INIS)

Ahmed, M.

2006-01-01

To assess the efficacy and complications of Nd: YAG laser iridotomy in patients with intermittent (sub-acute) angle closure glaucoma. Twenty-five eyes of twenty-three patients with periodic (intermittent) angle closure, selected in outpatient department, were kept on pilocarpine until YAG laser iridotomy was performed. After YAG laser iridotomy oral acetazolamide and topical dexamethasone was used to control post laser rise of IOP and inflammation respectively. Patency of iridotomy was confirmed and intra-ocular pressure was measured one hour after the procedure. Immediate complication, if any, was noted. Follow-up was done for six months. Prophylactic laser iridotomy was done in fellow eye with occludable angle. Levene's test for equality of variance and t-test for equality of means were used for statistical analysis. This study revealed a significant difference in IOP before and after YAG laser iridotomy (p = .002). Complete follow-up of 6 months was possible in 25 eyes of 23 subjects. After YAG Laser iridotomy, 21 (84%) eyes showed negative provocative test, intraocular pressure below 19mm Hg without medication and anterior chamber angle no more occludable and were labeled successful. Iridotomy remained patent in 96% of eyes. Iridotomy failed to reduce IOP in 4 (16%) eyes. The complications were minimal and transient. (author)

Minimally-invasive glaucoma surgeries (MIGS) for open angle glaucoma: A systematic review and meta-analysis.

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Lavia, Carlo; Dallorto, Laura; Maule, Milena; Ceccarelli, Manuela; Fea, Antonio Maria

2017-01-01

MIGS have been developed as a surgical alternative for glaucomatous patients. To analyze the change in intraocular pressure (IOP) and glaucoma medications using different MIGS devices (Trabectome, iStent, Excimer Laser Trabeculotomy (ELT), iStent Supra, CyPass, XEN, Hydrus, Fugo Blade, Ab interno canaloplasty, Goniscopy-assisted transluminal trabeculotomy) as a solo procedure or in association with phacoemulsification. Randomized control trials (RCT) and non-RCT (non randomized comparative studies, NRS, and before-after studies) were included. Studies with at least one year of follow-up in patients affected by primary open angle glaucoma, pseudoexfoliative glaucoma or pigmentary glaucoma were considered. Risk of Bias assessment was performed using the Cochrane Risk of Bias and the ROBINS-I tools. The main outcome was the effect of MIGS devices compared to medical therapy, cataract surgery, other glaucoma surgeries and other MIGS on both IOP and use of glaucoma medications 12 months after surgery. Outcomes measures were the mean difference in the change of IOP and glaucoma medication compared to baseline at one and two years and all ocular adverse events. The current meta-analysis is registered on PROSPERO (reference n° CRD42016037280). Over a total of 3,069 studies, nine RCT and 21 case series with a total of 2.928 eyes were included. Main concerns about risk of bias in RCTs were lack of blinding, allocation concealment and attrition bias while in non-RCTs they were represented by patients' selection, masking of participants and co-intervention management. Limited evidence was found based on both RCTs and non RCTs that compared MIGS surgery with medical therapy or other MIGS. In before-after series, MIGS surgery seemed effective in lowering both IOP and glaucoma drug use. MIGS showed a good safety profile: IOP spikes were the most frequent complications and no cases of infection or BCVA loss due to glaucoma were reported. Although MIGS seem efficient in the

Laser Trabeculoplasty Induces Changes in the Trabecular Meshwork Glycoproteome: A pilot study

OpenAIRE

Amelinckx, Adriana; Castello, Maria; Arrieta-Quintero, Esdras; Lee, Tinthu; Salas, Nelson; Hernandez, Eleut; Lee, Richard K.; Bhattacharya, Sanjoy K.; Parel, Jean-Marie A

2009-01-01

Laser trabeculoplasty (LT) is a commonly used modality of treatment for glaucoma. The mechanism by which LT lowers the intraocular pressure (IOP) is unknown. Using cat eyes, selective laser trabeculoplasty (SLT) with a Q-switched frequency doubled Nd:YAG laser was used to treat the trabecular meshwork (TM). Laser treated TM was then subjected to proteomic analysis for detection of molecular changes and histological analysis for the detection of structural and protein expression patterns. In a...

Laser-induced interactions

International Nuclear Information System (INIS)

Green, W.R.

1979-01-01

This dissertation discusses some of the new ways that lasers can be used to control the energy flow in a medium. Experimental and theoretical considerations of the laser-induced collision are discussed. The laser-induced collision is a process in which a laser is used to selectively transfer energy from a state in one atomic or molecular species to another state in a different species. The first experimental demonstration of this process is described, along with later experiments in which lasers were used to create collisional cross sections as large as 10 - 13 cm 2 . Laser-induced collisions utilizing both a dipole-dipole interaction and dipole-quadrupole interaction have been experimentally demonstrated. The theoretical aspects of other related processes such as laser-induced spin-exchange, collision induced Raman emission, and laser-induced charge transfer are discussed. Experimental systems that could be used to demonstrate these various processes are presented. An experiment which produced an inversion of the resonance line of an ion by optical pumping of the neutral atom is described. This type of scheme has been proposed as a possible method for constructing VUV and x-ray lasers

Clinical research of retinal laser photocoagulation and Ranibizumab on the treatment of neovascular glaucoma

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Wei-Peng Jiang

2015-10-01

Full Text Available AIM: To explore the improvement of visual function and the adverse reactions of retinal laser photocoagulation combined with ranibizumab for the treatment of neovascular glaucoma(NVG, to provide the basis for clinical treatment.METHODS: One hundred patients with 129 eyes in our hospital from January 2012 to June 2014 were selected. They were randomly divided into the observation group and the control group, 50 cases in each one. Patients in the control group(67 eyeswere treated with retinal laser photocoagulation, and those in the observation group(62 eyeswere given retinal laser photocoagulation combined with ranibizumab treatment. After the treatment, the degeneration of iris neovascularization, visual acuity, intraocular pressure, ocular fundus and the adverse reactions were evaluated. Optical coherence tomography(OCTwas used to detect retinal nerve fiber layer(RNFLthickness and visual field defect. RESULTS: The degeneration rate of the iris neovascularization in the observation group was 95.2%(59/62, higher than that of the control group 83.6%(56/67(PPPPPP>0.05.CONCLUSION: The treatment of NVG with laser photocoagulation combined with ranibizumab has good clinical efficacy, and can significantly improve the vision and retinal structure and function of the patients, and is safer.

Methods to reduce intraocular pressure on secondary glaucoma after severe eye burns

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A. V. Solovieva

2014-07-01

Full Text Available Purpose: Show the results of treatment of secondary glaucoma after severe eye burns.Methods: We observed 70 patients (108 eyes with severe burns the eyes and their consequences, secondary glaucoma was observed in 40 patients (58 eyes. All patients with secondary glaucoma received traditional antihypertensive therapy, with its failure to resort to antiglaucomatous surgery. Cataract extraction performed in 24 cases, 16 of them in combination with other surgery: the reconstruction of the anterior chamber, penetrating keratoplasty, sinustrabeculectomy, diode laser cyclocoagulation. Diode laser cy- clocoagulation performed 42 times in 8 of them in combination with other antiglaucomatous surgery: cataract surgery, reconstruction of the anterior chamber. Sinustrabeculectomy in patients with secondary glaucoma was performed in 7 cases, 4 of them with collagen implant drainage. Ahmed glaucoma drainage implant performed in 5 cases.Results: In 23 out of 58 (39.6% of long-term compensation glaucoma IOP was achieved antihypertensive therapy without sur- gery. After cataract extraction resistant compensated IOP was achieved in 10 cases, a temporary (1 to 42 months — in 11 cases, IOP is not reduced in 2 cases. After completing diode laser cyclocoagulation stable normalization of IOP occurred in 16 cases, the temporary (from 1 month to 2 years — in 20 cases, 4 cases of IOP reduction was not achieved. As a result sinustrabeculectomy in 4 cases IOP decreased, in one case the hypotensive effect is not there. After implantation Ahmed glaucoma valve in 2 cases was achieved stable normalization of IOP, in the 2 cases — the temporary; in 1 case developed endophthalmitis, and the device was removed.Conclusion: the immediate effect of antiglaucomatous treatment was 96.6%, but the high incidence of IOP decompensation (73.7% suggesting the need for continuous follow-up patients after severe eye burn injury, and a readiness to use other methods to reduce IOP.

Methods to reduce intraocular pressure on secondary glaucoma after severe eye burns

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A. V. Solovieva

2012-01-01

Full Text Available Purpose: Show the results of treatment of secondary glaucoma after severe eye burns.Methods: We observed 70 patients (108 eyes with severe burns the eyes and their consequences, secondary glaucoma was observed in 40 patients (58 eyes. All patients with secondary glaucoma received traditional antihypertensive therapy, with its failure to resort to antiglaucomatous surgery. Cataract extraction performed in 24 cases, 16 of them in combination with other surgery: the reconstruction of the anterior chamber, penetrating keratoplasty, sinustrabeculectomy, diode laser cyclocoagulation. Diode laser cy- clocoagulation performed 42 times in 8 of them in combination with other antiglaucomatous surgery: cataract surgery, reconstruction of the anterior chamber. Sinustrabeculectomy in patients with secondary glaucoma was performed in 7 cases, 4 of them with collagen implant drainage. Ahmed glaucoma drainage implant performed in 5 cases.Results: In 23 out of 58 (39.6% of long-term compensation glaucoma IOP was achieved antihypertensive therapy without sur- gery. After cataract extraction resistant compensated IOP was achieved in 10 cases, a temporary (1 to 42 months — in 11 cases, IOP is not reduced in 2 cases. After completing diode laser cyclocoagulation stable normalization of IOP occurred in 16 cases, the temporary (from 1 month to 2 years — in 20 cases, 4 cases of IOP reduction was not achieved. As a result sinustrabeculectomy in 4 cases IOP decreased, in one case the hypotensive effect is not there. After implantation Ahmed glaucoma valve in 2 cases was achieved stable normalization of IOP, in the 2 cases — the temporary; in 1 case developed endophthalmitis, and the device was removed.Conclusion: the immediate effect of antiglaucomatous treatment was 96.6%, but the high incidence of IOP decompensation (73.7% suggesting the need for continuous follow-up patients after severe eye burn injury, and a readiness to use other methods to reduce IOP.

La iridotomía periférica con Nd YAG láser en el síndrome de dispersión pigmentaria/glaucoma pigmentario Nd YAG laser peripheral iridotomy in the pigment dispersion syndrome/pigmentary glaucoma

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Francisco García González

2002-06-01

Full Text Available En 13 ojos con diagnóstico de síndrome de dispersión pigmentaria y 5 con glaucoma pigmentario, inicialmente se evaluaron la presión intraocular, los signos de dispersión pigmentaria, la relación excavación-papila y las alteraciones del campo visual; se realizó iridotomía periférica Nd YAG láser en los ojos con este síndrome y trabeculectomía a los que presentaban glaucoma pigmentario. Se chequearon cada 4 meses hasta 24 meses. Once ojos con iris cóncavo mostraron aplanamiento del iris y 2 con iris convexos no variaron con la iridotomía láser; en los 18 ojos disminuyeron evidentemente los signos de dispersión pigmentaria y la presión intraocular permaneció estable, la cual mejoró en los tratados con la trabeculectomía. En el síndrome de dispersión pigmentaria es muy frecuente la configuración cóncava del iris; la iridotomía lo aplana y evita el roce iridozonular, disminuyendo la dispersión y deposición de pigmento que prevendría el aumento de la presión intraocular y el glaucoma pigmentario.The intraocular pressure, the signs of pigment dispersion, the excavation-papilla relation and the alterations of the visual field were initially evaluated in 13 eyes with diagnosis of pigment dispersion syndrome and 5 with pigmentary glaucoma. Nd YAG laser perypheral iridotomy was performed in patients with this syndrome, whereas those who presented pigmentary glaucoma underwent trabeculectomy. They were checked every 4 months up to 24 months. 11 eyes with concave iris showed flattening of the iris and 2 with convex iris did not vary with laser iridotomy. An evident reduction of the signs of pigment dispersion was observed in the 18 eyes. The intraocular pressure remained stable and it improved in those treated with trabeculectomy. In the pigment dispersion syndrome it is very frequent the concave configuration of the iris; the iridotomy flattens it and avoids the iridozonular friction, reducing the dispersion and deposition of

Use of gonioscopy in medicare beneficiaries before glaucoma surgery.

Science.gov (United States)

Coleman, Anne L; Yu, Fei; Evans, Stacy J

2006-12-01

The American Academy of Ophthalmology Preferred Practice Patterns for angle closure and open-angle glaucoma (OAG) patients recommends performing bilateral gonioscopy upon initial presentation to evaluate the possibility of narrow angle or angle-closure glaucoma (ACG) and then repeating the examination at least every 5 years. This study aims to assess how commonly eye care providers perform gonioscopy before planned glaucoma surgery in OAG, anatomic narrow angle, and ACG in the Medicare population. Data obtained from a 5% random sample of Medicare beneficiaries undergoing glaucoma surgery in the United States in 1999 were retrospectively reviewed. The proportion of patients with evidence of at least one gonioscopic examination before glaucoma surgery was determined for the period of 1995 to 1999. Demographic and clinical factors potentially influencing the decision to perform gonioscopy were also examined. Overall, gonioscopy is apparently performed in 49% of Medicare beneficiaries during the 4 to 5 years preceding glaucoma surgery. This rate was significantly lower (P gonioscopy rates (P Gonioscopy examination before glaucoma surgery in Medicare beneficiaries is underused, undercoded, and/or miscoded, given current recommendations. Underuse is of particular concern in patients undergoing laser iridotomy as it is the diagnostic test of choice in ACG.

Selective laser trabeculoplasty

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Jing-Ming Shi

2012-12-01

Full Text Available The introduction of selective laser trabeculoplasty (SLT provided a new choice for the reduction of intraocular pressure (IOP in eyes with open angle glaucoma (OAG and ocular hypertension (OHT. SLT was demonstrated equally as effective as topical medical therapy and argon laser trabeculoplasty (ALT to lower IOP. It is a potentially repeatable procedure because of the lack of coagulation damage to the trabecular meshwork (TM and also effect in patients with previously failed ALT. SLT can be used to treat patients with OAG, pseudoexfoliation glaucoma, pigmentary glaucoma, normal-tension glaucoma, OHT, juvenile glaucoma, pseudophakic and aphakic glaucoma. Furthermore, SLT can be considered as a primary treatment option in patients who cannot tolerate or are noncompliant with medications, while not interfering with the success of future surgery. Its safety profiles include mild and transient inflammation, ocular pain and a small risk of moderate IOP elevations after the procedure. SLT is a safe and effective means of IOP reduction in eyes with OAG and OHT.

Structure-Function Correlations using Scanning Laser Polarimetry in Primary Angle-Closure Glaucoma and Primary Open Angle Glaucoma

Science.gov (United States)

Lee, Pei-Jung; Liu, Catherine Jui-Ling.; Wojciechowski, Robert; Bailey-Wilson, Joan E.; Cheng, Ching-Yu

2010-01-01

Purpose To assess the correlations between retinal nerve fiber layer (RNFL) thickness measured with scanning laser polarimetry (SLP) and visual field (VF) sensitivity in primary open angle glaucoma (POAG) and primary angle-closure glaucoma (PACG). Design Prospective, comparative, observational cases series Methods Fifty patients with POAG and 56 with PACG were examined using SLP with variable corneal compensation (GDx VCC) and Humphrey VF analyzer between August 2005 and July 2006 at Taipei Veterans General Hospital. Correlations between RNFL thickness and VF sensitivity, expressed as mean sensitivity (MS) in both decibel (dB) and 1/Lambert (L) scales, were estimated by Spearman's rank correlation coefficient (rs) and multivariate median regression models (pseudo R2). The correlations were determined globally and for six RNFL sectors and their corresponding VF regions. Results The correlation between RNFL thickness and MS (in dB) was weaker in the PACG group (rs = 0.38, P = 0.004, pseudo R2 = 0.17) than in the POAG group (rs = 0.51, P <0.001, pseudo R2 = 0.31), but the difference in the magnitude of correlation was not significant (P = 0.42).With Bonferroni correction, the structure-function correlation was significant in the superotemporal (rs = 0.62), superonasal (rs = 0.56), inferonasal (rs = 0.53), and inferotemporal (rs = 0.50) sectors in the POAG group (all P <0.001), while it was significant only in the superotemporal (rs = 0.53) and inferotemporal (rs = 0.48) sectors in the PACG group (both P <0.001). The results were similar when MS was expressed as 1/L scale. Conclusions Both POAG and PACG eyes had moderate structure-function correlations using SLP. Compared to eyes with POAG, fewer RNFL sectors have significant structure-function correlations in eyes with PACG. PMID:20202618

PRIMARY OPEN-ANGLE GLAUCOMA IN ONCOLOGIC PATIENTS

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A. A. Ryabtseva

2015-01-01

Full Text Available Background: Glaucoma-induced visual impairment negatively influences quality of life of oncologic patients. Yet, tumor in itself and methods of its treatment may promote glaucoma progression. Aim: To study characteristics and course of primary open-angle glaucoma in oncologic patients. Materials and methods: We analyzed case reports of 19 oncologic patients after primary open-angle glaucoma-related sinus trabeculectomy (34 eyes and laser cyclopexy (1 eye. Diagnosed malignancies included colorectal cancer in 5 patients, uterine body and cervical cancer in 4 patients, chronic lymphocytic leukemia in 1 patient, renal cell carcinoma in 1 patient, adrenal cancer in 1 patient, prostatic cancer in 1 patient, breast cancer in 1 patient, vulvar cancer in 1 patient, tongue root cancer in 1 patient. Antiglaucomatous surgery was accomplished during the first 5 years from the diagnosis of tumor in 14 patients. In 9 patients, chemotherapy or hormone therapy was continued by the time of surgery. Follow-up of the patients was undertaken in 4–12 months after the antiglaucomatous operation; it included routine ophthalmological examination and dry eye syndrome functional tests. Results: Duration of postoperative period was 4 months or more. All patients had uveitis postoperatively. During late postoperative period, choroidal detachment was diagnosed in 4 patients. Bleb scarring was found in 2 patients. All patients received hypotensive treatment postoperatively including selective and non-selective beta-adrenergic blockers. Conjunctival and corneal xerosis was observed in all patients. Conclusion: In oncologic patients undergoing antiglaucomatous surgery, long-term (4 months or more postoperative anti-inflammatory therapy is needed along with monthly ophthalmological follow-up during the first year after the operation. In patients with ongoing cytostatic drug treatment, artificial tear should be administrated.

[Secondary glaucoma in Paraguay. Etiology and incidence].

Science.gov (United States)

Strohl, A; Pozzi, S; Wattiez, R; Roesen, B; Miño de Kaspar, H; Klauss, V

1999-06-01

Glaucoma is the third-most-frequent cause of blindness in the world, with a total of 5.2 million blind people as a result of this disease; 80% live in developing countries. In Paraguay, after cataract it is the second-most-frequent-cause. Early detection of the risk factors and groups can help to avoid progress of this disease. Trauma, cataract and infectious uveitis represent special risks for developing secondary glaucoma, which is a more frequent cause of blindness in third-world countries than in industrialized nations. Until now there has been little data regarding the causes, disease course, and options for therapy. Therefore, secondary glaucoma was examined in Paraguay to obtain information on the situation in Latin America. The aim of the study was to explore the causes of secondary glaucoma for programs concerning prevention and therapy. From November 1996 to February 1997 patients with secondary glaucoma were examined at the University Hospital of Asunción, Paraguay. After the clinical examination the secondary glaucomas were classified. Patients with primary glaucoma were included in the same period of time as well in order to get the rate of secondary glaucoma. Altogether 293 patients were examined: 61 with secondary and 232 with primary glaucoma. The causes of secondary glaucoma in 73 eyes were: 20 (27%) with pseudoexfoliation glaucoma, 19 (26%) with post-traumatic glaucoma, 16 (22%) with neovascular glaucoma, 4 (5%) with lens-related glaucoma, 3 (4%) with glaucoma associated with ocular surgery, 2 (3%) with pigmentary and 2 (3%) with corticoid-induced glaucoma. A ratio of 4:1 primary glaucomas to secondary glaucomas was found. The development of special measures for prevention and early therapy is only possible if the causes of this severe disease are explored. The results of this study represent basic information and could help to introduce of prevention programs.

Matrix metalloproteinases and their tissue inhibitors after selective laser trabeculoplasty in pseudoexfoliative secondary glaucoma

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Strobbe Ernesto

2008-10-01

Full Text Available Abstract Background The aim of this study was to assess changes in metalloproteinases (MMP-2 and tissue inhibitor of metalloproteinases (TIMP-2 following selective laser trabeculoplasty (SLT in patients with pseudoexfoliative glaucoma (PEXG. Methods We enrolled 15 patients with PEXG and cataracts (PEXG-C group and good intraocular pressure (IOP controlled with β-blockers and dorzolamide eye drops who were treated by cataract phacoemulsification and 15 patients with pseudoexfoliative glaucoma (PEXG-SLT group. The PEXG-SLT patients underwent a trabeculectomy for uncontrolled IOP in the eye that showed increased IOP despite the maximum drug treatment with β-blockers and dorzolamide eye drops and after ineffective selective laser trabeculoplasty (SLT. The control group consisted of 15 subjects with cataracts. Aqueous humor was aspirated during surgery from patients with PEXG-C, PEXG-SLT and from matched control patients with cataracts during cataract surgery or trabeculectomy. The concentrations of MMP-2 and TIMP-2 in the aqueous humor were assessed with commercially available ELISA kits. Results In PEXG-SLT group in the first 10 days after SLT treatment a significant reduction in IOP was observed: 25.8 ± 1.9 vs 18.1.0 ± 1.4 mm/Hg (p The MMP-2 in PEXG-C was 57.77 ± 9.25 μg/ml and in PEXG-SLT was 58.52 ± 9.66 μg/ml (p Conclusion This case series suggest that IOP elevation after SLT can be a serious adverse event in some PEXG patients. The IOP increase in these cases would be correlated to the failure to decrease the TIMP-2/MMP-2 ratio. Trial registration Current Controlled Trials ISRCTN79745214

Malignant glaucoma after cataract surgery.

Science.gov (United States)

Varma, Devesh K; Belovay, Graham W; Tam, Diamond Y; Ahmed, Iqbal Ike K

2014-11-01

To report a series of eyes that developed malignant glaucoma after cataract surgery. Private academic practice, Toronto, Ontario, Canada. Retrospective case series. Eyes that developed malignant glaucoma after cataract surgery were treated with medical therapy. This was followed by laser iridozonulohyaloidotomy, anterior chamber reformation and intraocular lens (IOL) pushback, and finally with surgical iridozonulohyaloidovitrectomy if all other measures were unsuccessful. Refraction, intraocular pressure (IOP), gonioscopy, and anterior chamber depth (ACD) by anterior segment optical coherence tomography were analyzed before treatment and after treatment. The study evaluated 20 eyes of 18 female patients aged 44 to 86 years. Preoperatively, the mean refraction was +3.11 diopters (D) ± 2.89 (SD), the mean axial length was 21.30 ± 1.40 mm, and all eyes had narrow or closed angles. Malignant glaucoma was diagnosed a mean of 5.8 ± 7.1 weeks postoperatively. At diagnosis, the mean refraction was -2.15 ± 2.95 D; the mean ACD, 2.49 ± 0.72 mm; and the mean IOP, 28.3 ± 10.8 mm Hg on a mean of 1.3 ± 1.6 medications. Two eyes responded to cycloplegia, 7 to laser iridozonulohyaloidotomy, and 6 to anterior chamber reformation-IOL pushback; 5 eyes required vitrectomy. Posttreatment, the mean refraction was -0.56 ± 1.07 D; the mean ACD, 3.30 ± 0.50 mm; and the mean IOP, 14.4 ± 4.60 mm Hg on a mean of 1.2 ± 1.4 medications. Cycloplegia was discontinued in 17 eyes. Malignant glaucoma can occur after phacoemulsification and presents with myopic surprise, anterior chamber shallowing and, possibly, elevated IOP. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Retinal glutamate transporter changes in experimental glaucoma and after optic nerve transection in the rat.

Science.gov (United States)

Martin, Keith R G; Levkovitch-Verbin, Hana; Valenta, Danielle; Baumrind, Lisa; Pease, Mary Ellen; Quigley, Harry A

2002-07-01

High levels of glutamate can be toxic to retinal ganglion cells. Effective buffering of extracellular glutamate by retinal glutamate transporters is therefore important. This study was conducted to investigate whether glutamate transporter changes occur with two models of optic nerve injury in the rat. Glaucoma was induced in one eye of 35 adult Wistar rats by translimbal diode laser treatment to the trabecular meshwork. Twenty-five more rats underwent unilateral optic nerve transection. Two glutamate transporters, GLAST (EAAT-1) and GLT-1 (EAAT-2), were studied by immunohistochemistry and quantitative Western blot analysis. Treated and control eyes were compared 3 days and 1, 4, and 6 weeks after injury. Optic nerve damage was assessed semiquantitatively in epoxy-embedded optic nerve cross sections. Trabecular laser treatment resulted in moderate intraocular pressure (IOP) elevation in all animals. After 1 to 6 weeks of experimental glaucoma, all treated eyes had significant optic nerve damage. Glutamate transporter changes were not detected by immunohistochemistry. Western blot analysis demonstrated significantly reduced GLT-1 in glaucomatous eyes compared with control eyes at 3 days (29.3% +/- 6.7%, P = 0.01), 1 week (55.5% +/- 13.6%, P = 0.02), 4 weeks (27.2% +/- 10.1%, P = 0.05), and 6 weeks (38.1% +/- 7.9%, P = 0.01; mean reduction +/- SEM, paired t-tests, n = 5 animals per group, four duplicate Western blot analyses per eye). The magnitude of the reduction in GLT-1 correlated significantly with mean IOP in the glaucomatous eye (r(2) = 0.31, P = 0.01, linear regression). GLAST was significantly reduced (33.8% +/- 8.1%, mean +/- SEM) after 4 weeks of elevated IOP (P = 0.01, paired t-test, n = 5 animals per group). In contrast to glaucoma, optic nerve transection resulted in an increase in GLT-1 compared with the control eye (P = 0.01, paired t-test, n = 15 animals). There was no significant change in GLAST after transection. GLT-1 and GLAST were significantly

BILATERAL ACUTE ANGLE CLOSURE GLAUCOMA AND MYOPIA INDUCED BY LOW DOSAGE TOPIRAMATE

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Busra S. Arica

2014-09-01

Full Text Available Introduction: Topiramate, a sulfamate-substituted monosaccharide, has been shown to be effective in the treatment of epilepsy and migraine prophylaxis. However, acute secondary angle closure glaucoma and myopia has been shown to develop, especially during the first two weeks of treatment, in a small subset of patients. Case presentation: In the current case report, a 23 year old female patient developed acute myopia and angle closure glaucoma after one week topiramate treatment (25 mg/day for prophylaxis of migraine without aura. The patient was found to have significant conjunctival hyperemia, shallow anterior chamber, and bulging iris in both eyes. Grade 1 acute angle was detected in both eyes during gonioscopic examination. There was no pupillary block and intraocular pressure was 40 mmHg in both eyes. Refraction values were measured at -7.00 and -8.00 in the right and left eye, respectively. The patient and #8217;s visual acuity was at 0.1 to 0.2. Topiramate treatment was promptly discontinued, topical antiglaucomatous treatment was initiated, and laser peripheral iridotomy was performed on each eye. Intraocular pressure has declined to normal limits, refractive values were zero in both eyes and patient and #8217;s visual acuity has restored at follow-up period at 10 days after treatment. Conclusion: Side effects associated with topiramate treatments are known to disappear without long-term damage when the discontinuation of therapy and effective interventions are started early. Therefore, patients and their physicians should be alert for symptoms associated with acute secondary angle closure glaucoma and myopia; especially in the first weeks of topiramate treatment also with low dosage. [J Contemp Med 2014; 4(3.000: 168-171

Atypical birefringence pattern and the diagnostic ability of scanning laser polarimetry with enhanced corneal compensation in glaucoma.

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Rao, Harsha L; Yadav, Ravi K; Begum, Viquar U; Addepalli, Uday K; Senthil, Sirisha; Choudhari, Nikhil S; Garudadri, Chandra S

2015-03-01

To evaluate the effect of typical scan score (TSS), when within the acceptable limits, on the diagnostic performance of retinal nerve fibre layer (RNFL) parameters with the enhanced corneal compensation (ECC) protocol of scanning laser polarimetry (SLP) in glaucoma. In a cross-sectional study, 203 eyes of 160 glaucoma patients and 140 eyes of 104 control subjects underwent RNFL imaging with the ECC protocol of SLP. TSS was used to quantify atypical birefringence pattern (ABP) images. Influence of TSS on the diagnostic ability of SLP parameters was evaluated by receiver operating characteristic (ROC) regression models after adjusting for the effect of disease severity [based on mean deviation (MD)] on standard automated perimetry). Diagnostic abilities of all RNFL parameters of SLP increased when the TSS values were higher. This effect was statistically significant for TSNIT (coefficient: 0.08, p<0.001) and inferior average parameters (coefficient: 0.06, p=0.002) but not for nerve fibre indicator (NFI, coefficient: 0.03, p=0.21). In early glaucoma (MD of -5 dB), predicted area under ROC curve (AUC) for TSNIT average parameter improved from 0.642 at a TSS of 90 to 0.845 at a TSS of 100. In advanced glaucoma (MD of -15 dB), AUC for TSNIT average improved from 0.832 at a TSS of 90 to 0.947 at 100. Diagnostic performances of TSNIT and inferior average RNFL parameters with ECC protocol of SLP were significantly influenced by TSS even when the TSS values were within the acceptable limits. Diagnostic ability of NFI was unaffected by TSS values. © 2014 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Graft failure: III. Glaucoma escalation after penetrating keratoplasty.

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Greenlee, Emily C; Kwon, Young H

2008-06-01

Glaucoma after penetrating keratoplasty is a frequently observed post-operative complication and is a risk factor for graft failure. Penetrating keratoplasty performed for aphakic and pseudophakic bullous keratopathy and inflammatory conditions are more likely to cause postoperative glaucoma compared with keratoconus and Fuchs' endothelial dystrophy. The intraocular pressure elevation may occur immediately after surgery or in the early to late postoperative period. Early postoperative causes of glaucoma include pre-existing glaucoma, retained viscoelastic, hyphema, inflammation, pupillary block, aqueous misdirection, or suprachoroidal hemorrhage. Late causes include pre-existing glaucoma, angle-closure glaucoma, ghost cell glaucoma, suprachoroidal hemorrhage, and steroid-induced glaucoma. Determining the cause of IOP elevation can help guide therapeutic intervention. Treatments for refractory glaucoma include topical anti-glaucoma medications such as beta-adrenergic blockers. Topical carbonic anhydrase inhibitors, miotic agents, adrenergic agonists, and prostaglandin analogs should be used with caution in the post-keratoplasty patient, because of the possibility of corneal decompensation, cystoid macular edema, or persistent inflammation. Various glaucoma surgical treatments have reported success in post-keratoplasty glaucoma. Trabeculectomy with mitomycin C can be successful in controlling IOP without the corneal toxicity noted with 5-fluorouracil. Glaucoma drainage devices have successfully controlled intraocular pressure in postkeratoplasty glaucoma; this is, however, associated with increased risk of graft failure. Placement of the tube through the pars plana may improve graft success compared with implantation within the anterior chamber. In addition, cyclophotocoagulation remains a useful procedure for eyes that have refractory glaucoma despite multiple surgical interventions.

Detection of Progressive Retinal Nerve Fiber Layer Loss in Glaucoma Using Scanning Laser Polarimetry with Variable Corneal Compensation

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Medeiros, Felipe A.; Alencar, Luciana M.; Zangwill, Linda M.; Bowd, Christopher; Vizzeri, Gianmarco; Sample, Pamela A.; Weinreb, Robert N.

2010-01-01

Purpose To evaluate the ability of scanning laser polarimetry with variable corneal compensation to detect progressive retinal nerve fiber layer (RNFL) loss in glaucoma patients and patients suspected of having the disease. Methods This was an observational cohort study that included 335 eyes of 195 patients. Images were obtained annually with the GDx VCC scanning laser polarimeter, along with optic disc stereophotographs and standard automated perimetry (SAP) visual fields. The median follow-up time was 3.94 years. Progression was determined using commercial software for SAP and by masked assessment of optic disc stereophotographs performed by expert graders. Random coefficient models were used to evaluate the relationship between RNFL thickness measurements over time and progression as determined by SAP and/or stereophotographs. Results From the 335 eyes, 34 (10%) showed progression over time by stereophotographs and/or SAP. Average GDx VCC measurements decreased significantly over time for both progressors as well as non-progressors. However, the rate of decline was significantly higher in the progressing group (−0.70 μm/year) compared to the non-progressing group (−0.14 μm/year; P = 0.001). Black race and male sex were significantly associated with higher rates of RNFL loss during follow-up. Conclusions The GDx VCC scanning laser polarimeter was able to identify longitudinal RNFL loss in eyes that showed progression in optic disc stereophotographs and/or visual fields. These findings suggest that this technology could be useful to detect and monitor progressive disease in patients with established diagnosis of glaucoma or suspected of having the disease. PMID:19029038

Understanding practice patterns of glaucoma sub-specialists in India

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Nikhil S. Choudhari

2017-10-01

Full Text Available AIM: To obtain information on the prevailing practice patterns of glaucoma specialists in India. METHODS: Glaucoma specialists attending the Annual Conference of the Glaucoma Society of India (GSI were surveyed. This survey, conducted in 2013, was based on an interactive audience response system. RESULTS: The information was obtained from 146 glaucoma specialists. Approximately half (n=83; 57% had ≥10y of experience in managing glaucoma and were in institutional practice (n=74, 51%. Goldmann applanation tonometry was preferred by 103 (72% specialists whilst n=25 (17.4% used non-contact tonometer. Indentation gonioscopy was favoured by two-thirds (n=90, 66% whereas stereoscopic optic disc examination and visual fields using Humphrey perimeter was performed by a majority of the specialists surveyed (n=115, 86% and n=114; 83% respectively. Nearly three quarter specialists (n=96; 72% preferred optical coherence tomography for imaging. The primary choice for treatment of angle closure disease and primary open angle glaucoma was laser (iridotomy, n=117; 93% and medical management (prostaglandin analogue, n=104; 78%, respectively. Approximately only a third of the specialists surveyed (n=37; 28% were performing both trabeculectomy and implantation of a glaucoma drainage device and about half (n=64; 47% were not operating on congenital glaucoma at all. CONCLUSION: This survey has found conformance with preferred practice patterns in several areas of diagnosis and management of glaucoma, but there was diversity in a few areas. The information is a significant step towards improvement of glaucoma care in India, including planning for future strategies.

Glaucoma Medication Preferences among Glaucoma Specialists in Mexico

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Lazcano-Gomez, Gabriel; Alvarez-Ascencio, Daniela; Haro-Zuno, Cindy; Turati-Acosta, Mauricio; Garcia-Huerta, Magdalena; Jimenez-Arroyo, Jesus; Castañeda-Diez, Rafael; Castillejos-Chevez, Armando; Gonzalez-Salinas, Roberto; Dominguez-Dueñas, Francisca; Jimenez-Roman, Jesus

2017-01-01

Aim To determine the glaucoma specialists’ preferences for the different brands of topical glaucoma medications available in Mexico. Materials and methods A web-based survey was sent to 150 board-certified glaucoma specialists in Mexico, with 14 questions related to brand preferences for all glaucoma medications available in Mexico. Participants were asked to select each glaucoma medication class by brand and to state the factors leading to their choice. Results Data from 111 (74%) glaucoma s...

Gene therapy with brain-derived neurotrophic factor as a protection: retinal ganglion cells in a rat glaucoma model.

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Martin, Keith R G; Quigley, Harry A; Zack, Donald J; Levkovitch-Verbin, Hana; Kielczewski, Jennifer; Valenta, Danielle; Baumrind, Lisa; Pease, Mary Ellen; Klein, Ronald L; Hauswirth, William W

2003-10-01

To develop a modified adenoassociated viral (AAV) vector capable of efficient transfection of retinal ganglion cells (RGCs) and to test the hypothesis that use of this vector to express brain-derived neurotrophic factor (BDNF) could be protective in experimental glaucoma. Ninety-three rats received one unilateral, intravitreal injection of either normal saline (n = 30), AAV-BDNF-woodchuck hepatitis posttranscriptional regulatory element (WPRE; n = 30), or AAV-green fluorescent protein (GFP)-WPRE (n = 33). Two weeks later, experimental glaucoma was induced in the injected eye by laser application to the trabecular meshwork. Survival of RGCs was estimated by counting axons in optic nerve cross sections after 4 weeks of glaucoma. Transgene expression was assessed by immunohistochemistry, Western blot analysis, and direct visualization of GFP. The density of GFP-positive cells in retinal wholemounts was 1,828 +/- 299 cells/mm(2) (72,273 +/- 11,814 cells/retina). Exposure to elevated intraocular pressure was similar in all groups. Four weeks after initial laser treatment, axon loss was 52.3% +/- 27.1% in the saline-treated group (n = 25) and 52.3% +/- 24.2% in the AAV-GFP-WPRE group (n = 30), but only 32.3% +/- 23.0% in the AAV-BDNF-WPRE group (n = 27). Survival in AAV-BDNF-WPRE animals increased markedly and the difference was significant compared with those receiving either AAV-GFP-WPRE (P = 0.002, t-test) or saline (P = 0.006, t-test). Overexpression of the BDNF gene protects RGC as estimated by axon counts in a rat glaucoma model, further supporting the potential feasibility of neurotrophic therapy as a complement to the lowering of IOP in the treatment of glaucoma.

Glaucoma Surgery in Pregnancy: A Case Series and Literature Review

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Mohammad Reza Razeghinejad

2016-09-01

Full Text Available Glaucoma management in pregnant patients is a real challenge, especially when the glaucoma is not controlled with medications. We report the results of 6 incisional glaucoma surgeries for the management of medically uncontrolled glaucoma patients during pregnancy. This retrospective, case series was conducted on the 6 eyes of 3pregnant patients with uncontrolled glaucoma using maximum tolerable medications. Details of the glaucoma surgical management of these patients as well as their postoperative care and pregnancy and clinical outcomes on longitudinal follow-up are discussed. All 3 patients had juvenile open-angle glaucoma and were on various anti-glaucoma medications, including oral acetazolamide. The first case described underwent trabeculectomy without antimetabolites in both eyes because of uncontrolled intraocular pressure with topical medications. The surgery was done with topical lidocaine jelly and subconjunctival lidocaine during the second and third trimesters. The second patient had an Ahmed valve implantation in both eyes during the second and third trimesters because of uncontrolled IOP with topical medications and no response to selective laser trabeculoplasty. Surgery was done with topical tetracaine and subconjunctival and sub-Tenon’s lidocaine. The third case had a Baerveldt valve implantation under general anesthesia in the second trimester. In selected pregnant glaucoma patients with medically uncontrolled intraocular pressure threatening vision, incisional surgery may lead to good outcomes for the patient with no risk for the fetus.

Gonioscopic ab interno laser sclerostomy. A pilot study in glaucoma patients.

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Latina, M A; Melamed, S; March, W F; Kass, M A; Kolker, A E

1992-11-01

The purpose of this study is to evaluate the safety and efficacy of gonioscopic ab interno laser sclerostomy (GLS) in patients with glaucoma. The technique of GLS involves iontophoresis of methylene blue dye (1%) at the limbus to focally dye the sclera and to provide subsequent delivery of 10-microsecond pulsed laser energy to the dyed area through a goniolens. The laser emits at 660 nm, a wavelength that is maximally absorbed by the methylene blue dye. Patients were evaluated for fistula formation, intraocular pressure (IOP) reduction, and adverse sequelae. Thirty-eight treatments were performed in 35 eyes. Successful complete sclerostomies were achieved in 21 eyes (55%), which was associated with an acute mean reduction in IOP of 23 mmHg. Mean preoperative IOP for all patients was 35 mmHg, and 1 hour after treatment it was reduced to 18.5 mmHg. In 4 of the 38 treatments, there was no acute IOP reduction, and these eyes were judged as failures. The mean follow-up time was 8.2 months with a maximum follow-up of 15 months. By 9 months, 50% of patients had an IOP of 22 mmHg or lower. The number of antiglaucoma medications decreased from 3.1 to 1.7 for all eyes over the 15-month follow-up period. Hyphemas (13%) were the only major complication, and these resolved spontaneously. In only one case did the IOP increase after the procedure. The results of this trial indicate that GLS is technically feasible, and preliminary results of IOP control are promising.

Glaucoma

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Full Text Available ... Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Glaucoma Embedded video for NEI YouTube Videos: Glaucoma Embedded video for NEI YouTube Videos: Glaucoma NEI ...

Current Surgical Options for the Management of Pediatric Glaucoma

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Jose Morales

2013-01-01

Full Text Available Currently, there are numerous choices for the treatment of pediatric glaucoma depending on the type of glaucoma, the age of the patient, and other particularities of the condition discussed in this review. Traditionally, goniotomy and trabeculotomy ab externo have been the preferred choices of treatment for congenital glaucoma, and a variety of adult procedures adapted to children have been utilized for other types of pediatric glaucoma with variable results and complications. More recently, seton implantations of different types have become more popular to use in children, and newer techniques have become available including visualized cannulation and opening of Schlemm’s canal, deep sclerectomy, trabectome, and milder more directed cyclodestructive procedures such as endolaser and transcleral diode laser cyclophotocoagulation. This paper reviews the different surgical techniques currently available, their indications, results, and most common complications to allow the surgeon treating these conditions to make a more informed choice in each particular case. Although the outcome of surgical treatment in pediatric glaucoma has improved significantly, its treatment remains challenging.

Glaucoma Medication Preferences among Glaucoma Specialists in Mexico.

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Lazcano-Gomez, Gabriel; Alvarez-Ascencio, Daniela; Haro-Zuno, Cindy; Turati-Acosta, Mauricio; Garcia-Huerta, Magdalena; Jimenez-Arroyo, Jesus; Castañeda-Diez, Rafael; Castillejos-Chevez, Armando; Gonzalez-Salinas, Roberto; Dominguez-Dueñas, Francisca; Jimenez-Roman, Jesus

2017-01-01

To determine the glaucoma specialists' preferences for the different brands of topical glaucoma medications available in Mexico. A web-based survey was sent to 150 board-certified glaucoma specialists in Mexico, with 14 questions related to brand preferences for all glaucoma medications available in Mexico. Participants were asked to select each glaucoma medication class by brand and to state the factors leading to their choice. Data from 111 (74%) glaucoma specialists were collected. Imot (timolol 0.5%; Sophia, Mexico) was the preferred brand for the beta-blockers (BB) class by 71% (n = 79) of the participants. Azopt (brinzolamide 1%; Alcon Lab, US) was the preferred carbonic anhydrase inhibitor (CAI) by 54% (n = 60) of the glaucoma specialists. Lumigan (bimatoprost 0.01% and 0.03%; Allergan Inc., U.S.) was the first choice for the prostaglandin analogues (PGAs) in 62% (n = 70) of the answers. The most frequently prescribed alpha-agonist (AA) was Agglad (brimonidine 0.2%; Sophia Lab, Mexico) in 44% (n = 49) of the answers. Medication accessibility (31%), cost (29%), and recommended dose (23%) were the three main factors influencing the glaucoma specialists' preferences. Medication cost and accessibility, as well as posology, remain the main factors influencing brand preferences among glaucoma doctors. In our professional opinion, the therapeutic effect must be the leading factor when prescribing topical medications in the daily practice, so that patients receive the best treatment option. This survey provides an understanding of the decision-making process when prescribing glaucoma medications by glaucoma specialists in a Latin American developing country. Ideally, patient treatment should be individualized and aimed to achieve the best results possible for their specific condition. How to cite this article: Lazcano-Gomez G, Alvarez-Ascencio D, Haro-Zuno C, Turati-Acosta M, Garcia-Huerta M, Jimenez-Arroyo J, Castañeda-Diez R, Castillejos-Chevez A, Gonzalez

Glaucoma

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... glaucoma Images Eye Slit-lamp exam Visual field test Glaucoma References Anderson DR. The optic nerve in glaucoma. In: Tasman W, Jaeger EA, eds. Duane's Ophthalmology 2013 . Philadelphia, PA: Lippincott Williams & Wilkins; 2013:vol 3, chap 48. Giaconi JA, ...

Facts about Glaucoma

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... Information » Glaucoma » Facts About Glaucoma Listen Facts About Glaucoma This information was developed by the National Eye ... is the best person to answer specific questions. Glaucoma Defined What is Glaucoma? Glaucoma is a group ...

Role of imaging in glaucoma diagnosis and follow-up

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Vizzeri Gianmarco

2011-12-01

Full Text Available The purpose of the review is to provide an update on the role of imaging devices in the diagnosis and follow-up of glaucoma with an emphasis on techniques for detecting glaucomatous progression and the newer spectral domain optical coherence tomography instruments. Imaging instruments provide objective quantitative measures of the optic disc and the retinal nerve fiber layer and are increasingly utilized in clinical practice. This review will summarize the recent enhancements in confocal scanning laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography with an emphasis on how to utilize these techniques to manage glaucoma patients and highlight the strengths and limitations of each technology. In addition, this review will briefly describe the sophisticated data analysis strategies that are now available to detect glaucomatous change overtime.

What Is Glaucoma?

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... Stories Español Eye Health / Eye Health A-Z Glaucoma Sections What Is Glaucoma? What Are the Symptoms ... Diagnosis Glaucoma Treatment Glaucoma Vision Simulator What Is Glaucoma? Leer en Español: ¿Qué es el glaucoma? Written ...

Sustained Dorzolamide Release Prevents Axonal and Retinal Ganglion Cell Loss in a Rat Model of IOP-Glaucoma.

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Pitha, Ian; Kimball, Elizabeth C; Oglesby, Ericka N; Pease, Mary Ellen; Fu, Jie; Schaub, Julie; Kim, Yoo-Chun; Hu, Qi; Hanes, Justin; Quigley, Harry A

2018-04-01

To determine if one injection of a sustained release formulation of dorzolamide in biodegradable microparticles (DPP) reduces retinal ganglion cell (RGC) loss in a rat model of glaucoma. We injected either DPP or control microparticles intravitreally in rats. Two days later, unilateral ocular hypertension was induced by translimbal, diode laser treatment by a surgeon masked to treatment group. IOP and clinical exams were performed until sacrifice 6 weeks after laser treatment. RGC loss was measured by masked observers in both optic nerve cross-sections and RGC layer counts from retinal whole mounts. Cumulative IOP exposure was significantly reduced by DPP injection (49 ± 48 mm Hg × days in treated versus 227 ± 191 mm Hg × days in control microparticle eyes; P = 0.012, t -test). While control-injected eyes increased in axial length by 2.4 ± 1.7%, DPP eyes did not significantly enlarge (0.3 ± 2.2%, difference from control, P = 0.03, t -test). RGC loss was significantly less in DPP eyes compared with control microparticle injection alone (RGC axon count reduction: 21% vs. 52%; RGC body reduction: 25% vs. 50% [beta tubulin labeling]; P = 0.02, t -test). A single injection of sustained release DPP protected against RGC loss and axial elongation in a rat model of IOP glaucoma. Sustained release IOP-lowering medications have the potential to stop glaucoma progression.

Minimally invasive glaucoma surgery: current status and future prospects

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Richter GM

2016-01-01

Full Text Available Grace M Richter,1,2 Anne L Coleman11UCLA Stein Eye Institute, Department of Ophthalmology, University of California, Los Angeles, CA, USA; 2USC Eye Institute, Department of Ophthalmology, Keck School of Medicine of University of Southern California, Los Angeles, CA, USAAbstract: Minimally invasive glaucoma surgery aims to provide a medication-sparing, conjunctival-sparing, ab interno approach to intraocular pressure reduction for patients with mild-to-moderate glaucoma that is safer than traditional incisional glaucoma surgery. The current approaches include: increasing trabecular outflow (Trabectome, iStent, Hydrus stent, gonioscopy-assisted transluminal trabeculotomy, excimer laser trabeculotomy; suprachoroidal shunts (Cypass micro-stent; reducing aqueous production (endocyclophotocoagulation; and subconjunctival filtration (XEN gel stent. The data on each surgical procedure for each of these approaches are reviewed in this article, patient selection pearls learned to date are discussed, and expectations for the future are examined. Keywords: MIGS, microincisional glaucoma surgery, trabecular stent, Schlemm’s canal, suprachoroidal shunt, ab interno

Quality of life and visual acuity outcomes in the Registry in Glaucoma Outcomes Research study.

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Coleman, Anne L; Lum, Flora C; Gliklich, Richard E; Velentgas, Priscilla; Su, Zhaohui

2016-01-01

The RiGOR study evaluated the association of treatment and patient-reported outcomes for open-angle glaucoma patients. The Glaucoma Symptom Scale (National Eye Institute-Visual Function Questionnaire (NEI-VFQ) and visual acuity (VA) were collected as quality of life measures. The proportion of patients with improvement of at least two lines of vision was highest in the incisional surgery group (14.2% compared with 9.9% for laser surgery and 10.9% for additional medication). No clinically relevant differences were seen in benefit for the laser surgery or incisional surgery groups compared with additional medications for the Glaucoma Symptom Scale or NEI-VFQ measures or subscales. Differences in quality of life by race need to be explored in further studies.

Validity and cost-effectiveness of methods for screening of primary open angle glaucoma

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Fröschl, Barbara

2007-02-01

Full Text Available Health political background: About 950,000 people are affected by glaucoma in Germany, about 50% of which are undiagnosed. The German Ophthalmological Society and the German Association of Ophthalmologists recommend a screening for glaucoma according to their guidelines. The Federal Joint Committee disapproved a glaucoma-screening program on expense of the compulsory health insurance in 2004. Scientific background: Primary open angle glaucoma is diagnosed by evaluation of the optic disc, the retinal fibre layer and the visual field. The main examinations are ophthalmoscopy, scanning laser polarimetry, confocal scanning laser ophthalmoscopy, retinal thickness analysis and optical coherence tomography. Scotomas are diagnosed by perimetry (standard automated perimetry, short wavelength automated perimetry and frequency doubling perimetry. The intraocular pressure is the most important treatable risk factor and is measured by (contact or non-contact tonometry. Research questions: The aim of this HTA-report is to investigate the diagnostic validity and cost effectiveness of diagnostic techniques or combinations of these methods with respect to the use in a screening setting in Germany. Methods: A systematic literature research was performed in 35 international databases and yielded 2602 articles. Overall 57 publications were included for assessment, according to predefined selection criteria. Results: The 55 medical articles deal mainly with frequency doubling perimetry, confocal scanning laser ophthalmoscopy and scanning laser polarimetry. Few articles cover short wavelength automated perimetry, tonometry and ophalmocopic evaluations by ophthalmologists. The quality of the papers is generally low, as far as the evidence in respect of screening is concerned. No single method exists with both, high sensitivity and high specificity for screening purpose. Data are also not sufficient to recommend combinations of methods. Only two economic models on cost

Provider Education about Glaucoma and Glaucoma Medications during Videotaped Medical Visits

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Betsy Sleath

2014-01-01

Full Text Available Objective. The purpose of this study was to examine how patient, physician, and situational factors are associated with the extent to which providers educate patients about glaucoma and glaucoma medications, and which patient and provider characteristics are associated with whether providers educate patients about glaucoma and glaucoma medications. Methods. Patients with glaucoma who were newly prescribed or on glaucoma medications were recruited and a cross-sectional study was conducted at six ophthalmology clinics. Patients’ visits were videotape recorded and patients were interviewed after visits. Generalized estimating equations were used to analyze the data. Results. Two hundred and seventy-nine patients participated. Providers were significantly more likely to educate patients about glaucoma and glaucoma medications if they were newly prescribed glaucoma medications. Providers were significantly less likely to educate African American patients about glaucoma. Providers were significantly less likely to educate patients of lower health literacy about glaucoma medications. Conclusion. Eye care providers did not always educate patients about glaucoma or glaucoma medications. Practice Implications. Providers should consider educating more patients about what glaucoma is and how it is treated so that glaucoma patients can better understand their disease. Even if a patient has already been educated once, it is important to reinforce what has been taught before.

Reproducibility of retinal circulation measurements obtained using laser speckle flowgraphy-NAVI in patients with glaucoma

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Nakamura M

2011-08-01

Full Text Available Naoko Aizawa, Yu Yokoyama, Naoki Chiba, Kazuko Omodaka, Masayuki Yasuda, Takaaki Otomo, Masahiko Nakamura, Nobuo Fuse, Toru NakazawaDepartment of Ophthalmology, Tohoku University Graduate School of Medicine Sendai, Miyagi, JapanBackground: Laser speckle flowgraphy (LSFG enables noninvasive quantification of the retinal circulation in glaucoma patients. In this study, we tested the intrasession reproducibility of LSFG-NAVI, a modified LSFG technique.Methods: Sixty-five eyes from 33 subjects (male (M:female (F = 17:16 with a mean age of 49.4 ± 11.2 years were examined in this study. Two parameters indicating reproducibility – the coefficient of variation (COV and the intraclass correlation coefficient (ICC – were analyzed three times on the same day that mean blur rate (MBR was measured using LSFG-NAVI. The sites analyzed were the retinal artery and vein, the optic disk, and the choroid. Following classification according to the Glaucoma Hemifield Test (GHT; SITA-Standard 30-2 program, the COV and ICC were examined in patients with (GHT+; 38 eyes, M:F = 20:18, average age 48.9 ± 12.8 years and without (GHT-; 27 eyes, M:F = 13:14, average age 50.1 ± 8.7 years abnormal glaucomatous visual fields.Results: For all subjects, the intrasession reproducibility of MBR in the optic disk (COV: 3.4 ± 2.0; ICC: 0.95 and choroid (COV: 4.7 ± 3.4; ICC: 0.98 was excellent. The reproducibility for the retinal vein (COV: 8.4 ± 5.6, ICC: 0.90 and retinal artery (COV: 10.9 ± 9.9, ICC: 0.9 was moderate. MBRs in the optic disk had good reproducibility in both the GHT+ group (COV: 3.8 ± 2.0; ICC: 0.97 and the GHT− group (COV: 2.9 ± 2.1; ICC: 0.95. Local assessment of the optic disk in normal or glaucoma patients showed that the COVs of the quadrant optic disk areas were best in the temporal area of MBR (3.4%, 4.2%, respectively.Conclusion: LSFG-NAVI showed favorable reproducibility in evaluation of retinal circulation of glaucoma patients, particularly in

Topiramate-associated acute, bilateral, angle-closure glaucoma: case report

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Lucas Barasnevicius Quagliato

2013-02-01

Full Text Available This paper describes a topiramate induced acute bilateral angle-closure glaucoma. This rare adverse effect is an idiosyncratic reaction characterized by uveal effusion and lens forward displacement, leading to increased intraocular pressure and vision loss. We describe a 55 year-old white woman with migraine, spasmodic torticollis and essential tremor, who developed bilateral acute angle-closure glaucoma, one week after starting topiramate 25 mg/day. She was seen at the Ophthalmology Emergency Department of the Fundação João Penido Burnier (Campinas, SP, Brazil with a 4 hours history of blurry vision, ocular pain and bright flashes vision. Slit lamp examination revealed moderate conjunctival injection and corneal edema, and shallow anterior chambers. Intraocular pressure was 48 mmHg in both eyes. Fundoscopic examination findings were normal. She was treated with timolol, brimonidine, dorzolamide, pilocarpine, prednisone acetate eye drops and acetazolamide. One hour after those measures, as the intraocular pressure was 30 mmHg, she received a manitol intravenous injection and the intraocular pressure normalized. After 24 hours an iridotomy with Yag laser was performed. Topiramate was discontinued and she was totally recovered after one week.

Glaucoma Research Foundation

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... born with glaucoma. Read her story » Learn About Glaucoma Glaucoma is a complicated disease in which damage ... Christopher doesn't ever want to go blind » Glaucoma 360 Glaucoma 360 — three days of events uniting ...

Trabeculectomy versus Ahmed Glaucoma Valve implantation in neovascular glaucoma

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Shen, Christopher C; Salim, Sarwat; Du, Haiming; Netland, Peter A

2011-01-01

Purpose: To compare surgical outcomes in neovascular glaucoma patients who underwent trabeculectomy with mitomycin C versus Ahmed Glaucoma Valve implantation. Patients and methods: This was a retrospective comparative case series. We reviewed 40 eyes of 39 patients with underlying diagnosis of neovascular glaucoma, divided into two groups: Ahmed Glaucoma Valve (N = 20) and trabeculectomy with mitomycin C (N = 20). Surgical success was defined as 6 mm Hg ≤ intraocular pressure ≤21 mm Hg, with or without the use of glaucoma medications, with no further glaucoma surgery, and light perception or better vision. Early postoperative hypotony was defined as intraocular pressure Ahmed Glaucoma Valve group and 25 months (6–77 months) for the trabeculectomy group. Although the mean number of postoperative intraocular pressure-lowering medications was significantly higher in the trabeculectomy group compared with the Ahmed Glaucoma Valve group at 3 and 6 month time points, there was no statistically significant difference at any other time point. There was no statistically significant difference between both groups in postoperative visual acuity and intraocular pressure. Success was 70% and 65% at 1 year and 60% and 55% at 2 years after Ahmed Glaucoma Valve and trabeculectomy, respectively. Kaplan–Meier survival curve analysis showed no significant difference in success between the two groups (P = 0.815). Hyphema was the most common complication in both groups. Conclusion: We found similar results after trabeculectomy with mitomycin C and Ahmed Glaucoma Valve implantation in eyes with neovascular glaucoma. PMID:21468334

Clinical outcomes of Ahmed glaucoma valve implantation in pediatric glaucoma.

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Pakravan, Mohammad; Esfandiari, Hamed; Yazdani, Shahin; Doozandeh, Azadeh; Dastborhan, Zahra; Gerami, Ebrahim; Kheiri, Bahareh; Pakravan, Parastou; Yaseri, Mehdi; Hassanpour, Kiana

2018-03-01

To evaluate the outcomes of Ahmed glaucoma valve implantation in refractory primary congenital glaucoma as well as primary procedure in aphakic glaucoma. In this retrospective study, medical records of patients who underwent Ahmed glaucoma valve implantation for refractory glaucoma and aphakic glaucoma were reviewed. Primary outcome measures were the surgical success defined as intraocular pressure ≤21 mm Hg and decreased ≥20% and no secondary glaucoma surgery. Secondary outcome measures were the number of glaucoma medications, complications, best corrected visual acuity, and intraocular pressure. A total of 62 eyes of refractory primary congenital glaucoma patients (group 1) and 33 eyes of aphakic glaucoma patients (group 2) were included in our study. Mean follow-up was 51 ± 33 months in group 1 and 49 ± 41 months in group 2 (p = 0.82). The cumulative probability of success was 90% in both groups at the first year; however, the success rate was 52.5% in group 1 and 71.5% in group 2 at 5 years' follow-up visit. In group 1, the mean intraocular pressure ± standard deviation was 33.1 ± 8.6 mm Hg at the baseline and decreased to 17.1 ± 5.3 mm Hg at 1 year and 18.5 ± 6.4 at 3 years postoperatively (all p's glaucoma medications was 3 ± 0.7 that decreased to 2 ± 0.8 at final follow-up (p = 0.02). Ahmed glaucoma valve implantation has a moderate success rate in the management of refractory primary congenital glaucoma with an increased chance of tube-related complications. The surgical success rate is higher in case of primary Ahmed glaucoma valve implant for aphakic glaucoma with acceptable safety profile.

Glaucoma, Open-Angle

Science.gov (United States)

... Home » Statistics and Data » Glaucoma, Open-angle Listen Glaucoma, Open-angle Open-angle Glaucoma Defined In open-angle glaucoma, the fluid passes ... 2010 2010 U.S. Age-Specific Prevalence Rates for Glaucoma by Age and Race/Ethnicity The prevalence of ...

Equine Glaucoma.

Science.gov (United States)

Michau, Tammy Miller

2017-12-01

Glaucoma is a multifactorial neurodegenerative ocular disease leading to progressive loss of retinal ganglion cells and their axons that form the optic nerve, causing blindness. Knowledge of the pathogenesis and development of equine glaucoma is in its infancy compared with human glaucoma. Glaucoma occurs most commonly secondary to uveitis and may be underdiagnosed or misdiagnosed in horses suffering from uveitis. Recognition and clinical diagnosis of glaucoma in the horse is improved with clinician awareness and the availability of handheld tonometers. Therapy for glaucoma is aimed at decreasing aqueous humor production through medical and surgical means. Even with therapy, long-term prognosis for vision is poor. Copyright © 2017 Elsevier Inc. All rights reserved.

Induced Current Characteristics Due to Laser Induced Plasma and Its Application to Laser Processing Monitoring

International Nuclear Information System (INIS)

Madjid, Syahrun Nur; Idris, Nasrullah; Kurniawan, Koo Hendrik; Kagawa, Kiichiro

2011-01-01

In laser processing, suitable conditions for laser and gas play important role in ensuring a high quality of processing. To determine suitable conditions, we employed the electromagnetic phenomena associated with laser plasma generation. An electrode circuit was utilised to detect induced current due to the fast electrons propelled from the material during laser material processing. The characteristics of induced current were examined by changing parameters such as supplied voltage, laser pulse energy, number of laser shots, and type of ambient gas. These characteristics were compared with the optical emission characteristics. It was shown that the induced current technique proposed in this study is much more sensitive than the optical method in monitoring laser processing, that is to determine the precise focusing condition, and to accurately determine the moment of completion of laser beam penetration. In this study it was also shown that the induced current technique induced by CW CO 2 laser can be applied in industrial material processing for monitoring the penetration completion in a stainless steel plate drilling process.

EVOLUTION THE CONCEPTS OF ROLE OF INTRAOCULAR PRESSURE IN GLAUCOMA PROGRESSION (REVIEW

Directory of Open Access Journals (Sweden)

N. I. Kurysheva

2016-01-01

Full Text Available The role of elevated intraocular pressure (IOP in the progression of glaucoma optical neuropathy has emphasized repeatedly. The question about the role of elevated IOP as the underlying cause of glaucoma arose in the early 1960s. However, epidemiological studies have questioned the role of IOP as a diagnostic criterion for glaucoma, due to the relatively rare detection the disease among those with ocular hypertension and frequent detection of glaucoma with normal IOP. Multicenter studies determining the role of antihypertensive therapy in the treatment of glaucoma, have shown the importance of reducing IOP: decricing IOP at 1 mm Hg reduced the risk of developing glaucoma on 10-19%. In addition, it was found that the rate of glaucoma progression is very variable. It depends not only on the form of glaucoma, but also on other factors such as the stage of disease and therapy. Swedish study shown normal-tension glaucoma often progressed among the patients with more aggressive treatment such as argon laser trabeculoplasty or trabeculectomies. According to the study’s data, age is the most important risk factor for the progression of normal-tension glaucoma. Such questions as fluctuations in IOP, reduction of retrobulbar blood flow, antihypertensive treatment on the progression of glaucoma are still discussed. Despite the fact that the latter UKGTS multicenter study (2014 showed a decrease in the rate of progression of glaucoma in patients treated with latanoprost, a high percentage of non-treated patients didn’t have disease’s progression. In this regard, the role of IOP as main starting factor in glaucoma pathogenesis is still open.

Tank-Binding Kinase 1 (TBK1) Gene and Open-Angle Glaucomas (An American Ophthalmological Society Thesis).

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Fingert, John H; Robin, Alan L; Scheetz, Todd E; Kwon, Young H; Liebmann, Jeffrey M; Ritch, Robert; Alward, Wallace L M

2016-08-01

To investigate the role of TANK-binding kinase 1 ( TBK1 ) gene copy-number variations (ie, gene duplications and triplications) in the pathophysiology of various open-angle glaucomas. In previous studies, we discovered that copy-number variations in the TBK1 gene are associated with normal-tension glaucoma. Here, we investigated the prevalence of copy-number variations in cohorts of patients with other open-angle glaucomas-juvenile-onset open-angle glaucoma (n=30), pigmentary glaucoma (n=209), exfoliation glaucoma (n=225), and steroid-induced glaucoma (n=79)-using a quantitative polymerase chain reaction assay. No TBK1 gene copy-number variations were detected in patients with juvenile-onset open-angle glaucoma, pigmentary glaucoma, or steroid-induced glaucoma. A TBK1 gene duplication was detected in one (0.44%) of the 225 exfoliation glaucoma patients. TBK1 gene copy-number variations (gene duplications and triplications) have been previously associated with normal-tension glaucoma. An exploration of other open-angle glaucomas detected a TBK1 copy-number variation in a patient with exfoliation glaucoma, which is the first example of a TBK1 mutation in a glaucoma patient with a diagnosis other than normal-tension glaucoma. A broader phenotypic range may be associated with TBK1 copy-number variations, although mutations in this gene are most often detected in patients with normal-tension glaucoma.

Adapted motivational interviewing to improve the uptake of treatment for glaucoma in Nigeria: study protocol for a randomized controlled trial.

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Abdull, Mohammed M; Gilbert, Clare; McCambridge, Jim; Evans, Jennifer

2014-04-29

Glaucoma is a chronic eye disease associated with irreversible visual loss. In Africa, glaucoma patients often present late, with very advanced disease. One-off procedures, such as laser or surgery, are recommended in Africa because of lack of or poor adherence to medical treatment. However, acceptance of surgery is usually extremely low. To prevent blindness, adherence to treatment needs to improve, using acceptable, replicable and cost-effective interventions. After reviewing the literature and interviewing patients in Bauchi (Nigeria) motivational interviewing (MI) was selected as the intervention for this trial, with adaptation for glaucoma (MIG). MI is designed to strengthen personal motivation for, and commitment to a specific goal by eliciting and exploring a person's reasons for change within an atmosphere of acceptance and compassion. The aim of this study is to assess whether MIG increases the uptake of laser or surgery amongst glaucoma patients where this is the recommended treatment. The hypothesis is that MIG increases the uptake of treatment. This will be the first trial of MI in Africa. This is a hospital based, single centre, randomized controlled trial of MIG plus an information sheet on glaucoma and its treatment (the latter being "standard care") compared with standard care alone for glaucoma patients where the treatment recommended is surgery or laser.Those eligible for the trial are adults aged 17 years and above who live within 200 km of Bauchi with advanced glaucoma where the examining ophthalmologist recommends surgery or laser. After obtaining written informed consent, participants will be randomly allocated to MIG plus standard care, or standard care alone. Motivational interviewing will be delivered in Hausa or English by one of two MIG trained personnel. One hundred and fifty participants will be recruited to each arm. The primary outcome is the proportion of participants undergoing laser or surgery within two months of the date given

Laser-induced nuclear fusion

International Nuclear Information System (INIS)

Jablon, Claude

1977-01-01

Research programs on laser-induced thermonuclear fusion in the United States, in Europe and in USSR are reviewed. The principle of the fusion reactions induced is explained, together with the theoretical effects of the following phenomena: power and type of laser beams, shape and size of the solid target, shock waves, and laser-hydrodynamics coupling problems [fr

Glaucoma: Symptoms and Causes

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... types of glaucoma include the following: Open-angle glaucoma Open-angle glaucoma is the most common form ... re even aware of a problem. Angle-closure glaucoma Angle-closure glaucoma, also called closed-angle glaucoma, ...

Glaucoma Symptoms

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... up You can help find a cure for glaucoma Give now Signs & Symptoms The most common types ... have completely different symptoms. Symptoms of Open-Angle Glaucoma Most people who develop open-angle glaucoma don’ ...

Glaucoma and keratoprosthesis surgery: role of adjunctive cyclophotocoagulation.

Science.gov (United States)

Rivier, Delphine; Paula, Jayter S; Kim, Eva; Dohlman, Claes H; Grosskreutz, Cynthia L

2009-01-01

To evaluate the efficacy and safety of diode laser transscleral cyclophotocoagulation (DLTSC) to control intraocular pressure (IOP) in keratoprosthesis patients with uncontrolled glaucoma. Between 1993 and 2007, 18 eyes of 18 patients underwent DLTSC, either before (n=3), during (n=1), or after (n=14) keratoprosthesis surgery. Keratoprosthesis type I was used in 72%. All but one of these patients received an Ahmed Glaucoma Valve, either with or after the keratoprosthesis placement. Best-corrected visual acuity, IOP (assessed by digital palpation), number of medications, and complications were recorded preoperatively, at day 7, at 1, 3, and 6 months then every 6 months postoperatively. Mean follow-up was 26.6+/-19.6 months (mean+/-SD) and mean age was 50.1+/-15.6 years. Glaucoma was identified in 11 eyes before keratoprosthesis surgery and in 7 eyes after. Mean postoperative IOP was significantly reduced at 6, 12, 24, 36, and 48 months after DLTSC. DLTSC was repeated in 6 eyes. At final visit, mean best-corrected visual acuity was not decreased and there were no statistically significant differences in the number of glaucoma medications. Two patients had complications after DLTSC: a conjunctival dehiscence and a fungal endophthalmitis. DLTSC has beneficial long-term effects in the control of IOP and can be considered in the management of keratoprosthesis patients with refractory glaucoma.

Pulsed UV laser technologies for ophthalmic surgery

International Nuclear Information System (INIS)

Razhev, A M; Bagayev, S N; Churkin, D S; Kargapol’tsev, E S; Chernykh, V V; Iskakov, I A; Ermakova, O V

2017-01-01

The paper provides an overview of the results of multiyear joint researches of team of collaborators of Institute of Laser Physics SB RAS together with NF IRTC “Eye Microsurgery” for the period from 1988 to the present, in which were first proposed and experimentally realized laser medical technologies for correction of refractive errors of known today as LASIK, the treatment of ophthalmic herpes and open-angle glaucoma. It is proposed to carry out operations for the correction of refractive errors the use of UV excimer KrCl laser with a wavelength of 222 nm. The same laser emission is the most suitable for the treatment of ophthalmic herpes, because it has a high clinical effect, combined with many years of absence of recrudescence. A minimally invasive technique of glaucoma operations using excimer XeCl laser (λ=308 nm) is developed. Its wavelength allows perform all stages of glaucoma operations, while the laser head itself has high stability and lifetime, will significantly reduce operating costs, compared with other types of lasers. (paper)

Glaucoma progression detection by retinal nerve fiber layer measurement using scanning laser polarimetry: event and trend analysis.

Science.gov (United States)

Moon, Byung Gil; Sung, Kyung Rim; Cho, Jung Woo; Kang, Sung Yong; Yun, Sung-Cheol; Na, Jung Hwa; Lee, Youngrok; Kook, Michael S

2012-06-01

To evaluate the use of scanning laser polarimetry (SLP, GDx VCC) to measure the retinal nerve fiber layer (RNFL) thickness in order to evaluate the progression of glaucoma. Test-retest measurement variability was determined in 47 glaucomatous eyes. One eye each from 152 glaucomatous patients with at least 4 years of follow-up was enrolled. Visual field (VF) loss progression was determined by both event analysis (EA, Humphrey guided progression analysis) and trend analysis (TA, linear regression analysis of the visual field index). SLP progression was defined as a reduction of RNFL exceeding the predetermined repeatability coefficient in three consecutive exams, as compared to the baseline measure (EA). The slope of RNFL thickness change over time was determined by linear regression analysis (TA). Twenty-two eyes (14.5%) progressed according to the VF EA, 16 (10.5%) by VF TA, 37 (24.3%) by SLP EA and 19 (12.5%) by SLP TA. Agreement between VF and SLP progression was poor in both EA and TA (VF EA vs. SLP EA, k = 0.110; VF TA vs. SLP TA, k = 0.129). The mean (±standard deviation) progression rate of RNFL thickness as measured by SLP TA did not significantly differ between VF EA progressors and non-progressors (-0.224 ± 0.148 µm/yr vs. -0.218 ± 0.151 µm/yr, p = 0.874). SLP TA and EA showed similar levels of sensitivity when VF progression was considered as the reference standard. RNFL thickness as measurement by SLP was shown to be capable of detecting glaucoma progression. Both EA and TA of SLP showed poor agreement with VF outcomes in detecting glaucoma progression.

Secondary glaucoma in CAPN5-associated neovascular inflammatory vitreoretinopathy

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Cham A

2016-06-01

Full Text Available Abdourahman Cham,1,2 Mayank Bansal,3 Himanshu K Banda,4 Young Kwon,1 Paul S Tlucek,1 Alexander G Bassuk,5 Stephen H Tsang,6,7 Warren M Sobol,8 James C Folk,1 Steven Yeh,4 Vinit B Mahajan1,2 1Department of Ophthalmology and Visual Sciences, 2Omics Laboratory, University of Iowa, Iowa City, IA, USA; 3Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India; 4Department of Ophthalmology, Emory University School of Medicine, Atlanta, GA, 5Department of Pediatrics, University of Iowa, Iowa City, IA, 6Barbara and Donald Jonas Laboratory of Stem Cells and Regenerative Medicine and Bernard and Shirlee Brown Glaucoma Laboratory, Department of Pathology and Cell Biology, Institute of Human Nutrition, College of Physicians and Surgeons, Columbia University, 7Edward S Harkness Eye Institute, New York-Presbyterian Hospital, New York, NY, 8Retina Physicians & Surgeons, Inc., Dayton, OH, USA Objective: The objective of this study was to review the treatment outcomes of patients with secondary glaucoma in cases of autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV, a hereditary autoimmune uveitis due to mutations in CAPN5. Patients and methods: A retrospective, observational case series was assembled from ADNIV patients with secondary glaucoma. The main outcome measures were intraocular pressure (IOP, visual acuity, use of antiglaucoma medications, ocular surgeries, and adverse outcomes. Perimetry and optic disk optical coherence tomography (OCT were also analyzed. Results: Nine eyes of five ADNIV patients with secondary glaucoma were reviewed. Each received a fluocinolone acetonide (FA implant for the management of posterior uveitis. Following implantation, no eyes developed neovascular glaucoma. Five eyes (in patients 1, 2, and 5 required Ahmed glaucoma valve surgery for the management of steroid-responsive glaucoma. Patient 2 also developed angle closure with iris bombe and underwent laser

Infrared laser-induced chemical reactions

International Nuclear Information System (INIS)

Katayama, Mikio

1978-01-01

The experimental means which clearly distinguishes between infrared ray-induced reactions and thermal reactions has been furnished for the first time when an intense monochromatic light source has been obtained by the development of infrared laser. Consequently, infrared laser-induced chemical reactions have started to develop as one field of chemical reaction researches. Researches of laser-induced chemical reactions have become new means for the researches of chemical reactions since they were highlighted as a new promising technique for isotope separation. Specifically, since the success has been reported in 235 U separation using laser in 1974, comparison of this method with conventional separation techniques from the economic point of view has been conducted, and it was estimated by some people that the laser isotope separation is cheaper. This report briefly describes on the excitation of oscillation and reaction rate, and introduces the chemical reactions induced by CW laser and TEA CO 2 laser. Dependence of reaction yield on laser power, measurement of the absorbed quantity of infrared ray and excitation mechanism are explained. Next, isomerizing reactions are reported, and finally, isotope separation is explained. It was found that infrared laser-induced chemical reactions have the selectivity for isotopes. Since it is evident that there are many examples different from thermal and photo-chemical reactions, future collection of the data is expected. (Wakatsuki, Y.)

Lens dislocation has a possible relationship with laser iridotomy

Directory of Open Access Journals (Sweden)

Mutoh T

2012-12-01

Full Text Available Tetsuya Mutoh,1,2 Kevin F Barrette,2 Yukihiro Matsumoto,1 Makoto Chikuda11Department of Ophthalmology, Dokkyo Medical University Koshigaya Hospital, Koshigaya City, Saitama, Japan; 2Department of Ophthalmology, Boston University School of Medicine, Boston, MA, USAAbstract: We report our recent experience of four eyes with spontaneous lens dislocation in four patients with no history of trauma or any systemic disease associated with zonular dialysis. Lens dislocation developed with 0.5 to 6 months following laser iridotomy. All patients were male and two eyes were complicated with acute primary angle closure glaucoma preoperatively. Case 1 showed bilateral lens dislocation, while cases 2 and 3 involved unilateral lens dislocation. Cases 2 and 3 showed lenses completely dislocated into the vitreous cavity. All cases needed lens removal and scleral fixation of intraocular lenses. Final visual acuity was 1.2 in all cases. We suspect that laser iridotomy may induce localized zonular dialysis that results in progressive zonular weakness, leading to lens dislocation.Keywords: lens dislocation, laser iridotomy, primary angle closure glaucoma

Laser Trabeculoplasty Induces Changes in the Trabecular Meshwork Glycoproteome: A pilot study

Science.gov (United States)

Amelinckx, Adriana; Castello, Maria; Arrieta-Quintero, Esdras; Lee, Tinthu; Salas, Nelson; Hernandez, Eleut; Lee, Richard K.; Bhattacharya, Sanjoy K.; Parel, Jean-Marie A

2009-01-01

Laser trabeculoplasty (LT) is a commonly used modality of treatment for glaucoma. The mechanism by which LT lowers the intraocular pressure (IOP) is unknown. Using cat eyes, selective laser trabeculoplasty (SLT) with a Q-switched frequency doubled Nd:YAG laser was used to treat the trabecular meshwork (TM). Laser treated TM was then subjected to proteomic analysis for detection of molecular changes and histological analysis for the detection of structural and protein expression patterns. In addition, the protein glycosylation patterns of laser treated and non-treated TM was assessed and differentially glycosylated proteins were proteomically identified. SLT laser treatment to the TM resulted in elevated glycosylation levels compared to non-lasered TM. TM laser treatment also resulted in protein expression levels changes of several proteins. Elevated levels of biglycan, keratocan and prolargin were detected in laser treated TM compared to non-lasered controls. Further investigation is anticipated to provide insight into how glycosylation changes affect TM proteins and TM regulation of aqueous outflow in response to laser trabeculoplasty. PMID:19432485

The Ahmed Glaucoma Valve in Refractory Glaucoma: Experiences in Southwest Ethiopia.

Science.gov (United States)

Gessesse, Girum W

2015-07-01

The management of refractory glaucoma is a challenging task for any glaucoma surgeon. This study is aimed to evaluate the efficacy of Ahmed Glaucoma Valve implantation in refractory glaucomas in South-West Ethiopia. A retrospective review was conducted on the charts of consecutive patients treated with Ahmed glaucoma valve implantation at Jimma University Specialized Hospital between August 2012 and August 2014. Success was defined as Intraocular Pressure (IOP) less than 22 mm Hg and greater than 5mm Hg at 6 months, with at least 30% reduction from baseline, without medical therapy (complete success) or either with or without medication (qualified successes). A total of 12 eyes of 11 patients were included. The mean age of patients was 40.7 (SD= 19.0) years; 63.6% of them were males. The main types of glaucoma were pseudoexfoliative (3 eyes), uveitic (2 eyes), chronic angle closure (2 eyes) and Juvenile Open Angle (JOAG) (2 eyes). The mean IOP was reduced from preoperative level (32.75±7.14 mmHg) to (15.75 ±4.35 mmHg) at six postoperative months, (PAhmed glaucoma valve implant appears to be effective and relatively safe for treating complicated glaucomas with success rate comparable with those reported from other studies. Ahmed glaucoma valve, refractory glaucoma, complications, Ethiopia.

Glaucoma

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Full Text Available ... YouTube Videos: Glaucoma Embedded video for NEI YouTube Videos: Glaucoma ... *PDF files require the free Adobe® Reader® software for viewing. This website is maintained by the ...

Laser induced energy transfer

International Nuclear Information System (INIS)

Falcone, R.W.

1979-01-01

Two related methods of rapidly transferring stored energy from one excited chemical species to another are described. The first of these, called a laser induced collision, involves a reaction in which the energy balance is met by photons from an intense laser beam. A collision cross section of ca 10 - 17 cm 2 was induced in an experiment which demonstrated the predicted dependence of the cross section on wavelength and power density of the applied laser. A second type of laser induced energy transfer involves the inelastic scattering of laser radiation from energetically excited atoms, and subsequent absorption of the scattered light by a second species. The technique of producing the light, ''anti-Stokes Raman'' scattering of visible and infrared wavelength laser photons, is shown to be an efficient source of narrow bandwidth, high brightness, tunable radiation at vacuum ultraviolet wavelengths by using it to excite a rare gas transition at 583.7 A. In addition, this light source was used to make the first measurement of the isotopic shift of the helium metastable level at 601 A. Applications in laser controlled chemistry and spectroscopy, and proposals for new types of lasers using these two energy transfer methods are discussed

Molteno3 Implantation as Primary Glaucoma Surgery

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Juha O. Välimäki

2014-01-01

Full Text Available Purpose. To determine the outcome of Molteno3 implantation as primary glaucoma surgery and to analyze the factors influencing the surgical outcome. Methods. This is a retrospective clinical study of 106 consecutive eyes (97 patients with no previous glaucoma surgery. Surgical failure was defined as an IOP > 21 mmHg or less than a 20% reduction below baseline, or IOP ≤ 5 mmHg, on two consecutive visits after 3 months follow-up, or reoperation for glaucoma or loss of light perception. Results. At the end of the follow-up (mean, 35 months; range, 12–71 months, the mean postoperative IOP (14.2 ± 4.4 mmHg was statistically significantly lower than the preoperative IOP (35.2 ± 9.7 mmHg (P<0.001. Life-table success rates were 97%, 94%, and 91% after follow-up of 12, 24, and 36 months, respectively. Success rate for an IOP ≤ 18 mmHg was 77% at the last visit. Success was not influenced by previous cataract surgery, sex, age, laser trabeculoplasty (LTP, preoperative IOP, or number of antiglaucoma medications. Forty-seven eyes had 66 postoperative complications. Conclusions. The primary Molteno3 implant provided significant IOP lowering with minimal and manageable complications in uncontrolled glaucoma. Neither previous cataract surgery nor LTP had any detrimental effect on surgical success.

Glaucoma

Science.gov (United States)

Glaucoma is a group of diseases that can damage the eye's optic nerve. It is a leading ... no symptoms at first. Without treatment, people with glaucoma will slowly lose their peripheral, or side vision. ...

Comparison of Optical Coherence Tomography Angiography and Laser Speckle Flowgraphy for the Diagnosis of Normal-Tension Glaucoma

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Asuka Takeyama

2018-01-01

Full Text Available Purpose. To compare optical coherence tomography angiography (OCT-A and laser speckle flowgraphy (LSFG for the diagnosis of normal-tension glaucoma (NTG. Methods. Twenty-eight eyes of 28 patients with NTG and 25 eyes of 25 normal subjects matched for age, refractive errors, systemic blood pressure, and central corneal thickness were evaluated. OCT-A was used to measure whole image vessel density, inside disc vessel density, and peripapillary vessel density; using LSFG, mean blur rate (MBR inside the whole optic nerve head (ONH area (MBRA, and MBR of the vessel area (MBRV and tissue area (MBRT inside the ONH, were determined. Receiver operating characteristic (ROC curves and areas under the ROC (AUROC were used to assess the diagnostic ability of each variable. Results. The AUROC for OCT-A whole image vessel density (0.950 was significantly greater than that for OCT-A peripapillary vessel density (0.830 and for all LSFG parameters (MBRA = 0.793, MBRV = 0.601, and MBRT = 0.61 (P<0.001. The AUROC for OCT-A inside disc vessel density (0.931 was significantly greater than that for all LSFG parameters (P<0.005. Conclusions. OCT-A vessel density had a higher glaucoma diagnostic ability compared to all LSFG parameters in patients with NTG.

Glaucoma

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Full Text Available ... Eye Disease Dilated Eye Exam Dry Eye For Kids Glaucoma Healthy Vision Tips Leber Congenital Amaurosis Low Vision Refractive Errors Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Glaucoma Embedded ...

Glaucoma

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Full Text Available ... Diabetic Eye Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino Program Vision and ... Kids Glaucoma Healthy Vision Tips Leber Congenital Amaurosis Low Vision Refractive Errors Retinopathy of Prematurity Science Spanish ...

Glaucoma

Medline Plus

Full Text Available ... Diabetic Eye Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino Program Vision and Aging ... Kids Glaucoma Healthy Vision Tips Leber Congenital Amaurosis Low Vision Refractive Errors Retinopathy of Prematurity Science Spanish Videos ...

Predictors of success in selective laser trabeculoplasty for primary open angle glaucoma in Chinese

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Lee JW

2014-09-01

Full Text Available Jacky WY Lee,1,2 Catherine CL Liu,3 Jonathan CH Chan,4 Raymond LM Wong,5 Ian YH Wong,2 Jimmy SM Lai2 1The Department of Ophthalmology, Caritas Medical Centre, Hong Kong, SAR, People’s Republic of China; 2The Department of Ophthalmology, The University of Hong Kong, Hong Kong, SAR, People’s Republic of China; 3Department of Applied Mathematics, The Hong Kong Polytechnic University, Hong Kong, SAR, People’s Republic of China; 4The Department of Ophthalmology, Queen Mary Hospital, Hong Kong, SAR, People’s Republic of China; 5The Department of Ophthalmology and Visual Sciences, Hong Kong Eye Hospital, Hong Kong, SAR, People’s Republic of China Purpose: To determine the predictors of success for adjuvant selective laser trabeculoplasty (SLT in Chinese primary open angle glaucoma (POAG patients. Methods: This prospective study recruited Chinese subjects with unilateral or bilateral POAG currently taking medication to reduce intraocular pressure (IOP. All subjects received a single session of 360° SLT treatment and continued their medications for 1 month. SLT success was defined as IOP reduction ≥20% at 1 month. The following covariates were analyzed in both groups via univariate and multivariate analyses: age, sex, lens status, initial IOPs, post-SLT IOPs, number and type of medications, SLT shots and energy, and pre-SLT investigations.Results: In 51 eyes of 33 POAG subjects, the success rate of SLT was 47.1%. Certain groups of patients were associated with greater success using univariate analysis. These groups included the following: older age (coefficient =0.1; OR: 1.1; P=0.0003, a higher pre-SLT IOP (coefficient =0.3; OR: 1.3; P=0.0005, using four types of antiglaucoma medication (coefficient =2.1; OR: 8.4; P=0.005, a greater degree of spherical equivalent (coefficient =2.1; OR: 8.4; P=0.005, and the use of a topical carbonic anhydrase inhibitor (coefficient =1.7; OR: 6.0; P=0.003. None of the covariates were significant using

Dry eye, sleep quality, and mood status in glaucoma patients receiving prostaglandin monotherapy were comparable with those in non-glaucoma subjects.

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Shugyoku Ra

Full Text Available Prior studies suggested that glaucoma patients suffer worse dry eye and mood and sleep disorders than non-glaucoma subjects. Prostaglandin analogues are first-line therapy for glaucoma, inducing few instillation problems and sufficient pressure-reduction effects. This study compared dry eye, sleep quality, and mood status between glaucoma patients receiving prostaglandin monotherapy and non-glaucoma subjects.This cross-sectional study evaluated 1520 patients (579 males and 941 females for glaucoma status and dry eye-related symptoms (dryness, eye fatigue, photophobia, pain, blurring and signs (Schirmer test, tear break-up time, corneal staining scores. Of the total cohort, 93 patients were also evaluated by Pittsburgh sleep quality index (PSQI and hospital anxiety and depression score (HADS. Inclusion criteria were consecutive patients ≥ 51 years of age and best-corrected visual acuity ≥ 20/25. Glaucoma patients included those treated with prostaglandin or a fixed combination including prostaglandin. Exclusion criteria were history of ocular surgery within one month. Data were analyzed using the chi-square or Mann-Whitney U tests, at 5% significance.There were no significant differences in dry eye-related signs and symptoms between the control (n = 1431, mean age of 66.9 years and glaucoma groups (n = 89, 67.9 years. The psychiatric sub-analysis of the control (n = 61, 66.2 years and glaucoma groups (n = 32, 67.3 years revealed mean scores of 5.02 ± 3.10 and 5.16 ± 3.46 for PSQI (normal range ≤ 5, 9.47 ± 5.61 and 9.42 ± 7.36 for HADS (normal range ≤ 10, 4.84 ± 3.22 and 4.71 ± 3.45 for anxiety (normal range ≤ 5, and 4.63 ± 3.05 and 4.71 ± 4.40 for depression (normal range ≤ 5, respectively, without statistical significance.Our results were comparable between glaucoma patients on prostaglandin monotherapy and non-glaucoma subjects for dry eye-related clinical manifestations, sleep quality, and mood status.

Glaucoma

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Full Text Available ... YouTube Videos » NEI YouTube Videos: Glaucoma Listen NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration ... Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Glaucoma Embedded video for NEI YouTube Videos: ...

Glaucoma management in patients with osteo-odonto-keratoprosthesis (OOKP): the Singapore OOKP Study.

Science.gov (United States)

Kumar, Rajesh S; Tan, Donald T H; Por, Yong-Ming; Oen, Francis T; Hoh, Sek-Tien; Parthasarathy, Anand; Aung, Tin

2009-01-01

To report diagnostic modalities and treatment options for glaucoma in eyes with osteo-odonto keratoprosthesis (OOKP). Eyes that underwent OOKP were evaluated for glaucoma at the time of the first postoperative visit, then at 1 and 3 months after the procedure, and thereafter every 6 months. All eyes underwent stereo-biomicroscopic optic nerve head (ONH) assessment, kinetic (Goldmann perimetry) and automated static visual field testing, ONH photography, Heidelberg retina tomograph, scanning laser polarimetery (GDx), and optical coherence tomography. Treatment of glaucoma was also reviewed. Average follow-up period was 19.1 (range: 5 to 31) months. Of the 15 eyes that underwent OOKP, 5 eyes had preexisting glaucoma. None of the other 10 eyes developed glaucoma after OOKP. ONH photography and visual field testing were the most reliable methods to assess status of the disease, whereas Heidelberg retina tomograph and optical coherence tomography could be performed with reasonable reproducibility and quality; GDx imaging was poor. All patients with glaucoma were treated with oral acetazolamide 500 mg twice a day. Transscleral cyclophotocoagulation was performed in 3 eyes at stage 2 of OOKP surgery. Progression of glaucoma was noted in 2 eyes on the basis of optic disc photographs and automated perimetry. Visual field testing and optic disc assessment with optic disc photographs seem to be effective methods to monitor eyes with OOKP for glaucoma. Treatment strategies include oral medications to lower intraocular pressure and cyclophotocoagulation.

Laser-induced damage in optical materials

CERN Document Server

Ristau, Detlev

2014-01-01

Dedicated to users and developers of high-powered systems, Laser-Induced Damage in Optical Materials focuses on the research field of laser-induced damage and explores the significant and steady growth of applications for high-power lasers in the academic, industrial, and military arenas. Written by renowned experts in the field, this book concentrates on the major topics of laser-induced damage in optical materials and most specifically addresses research in laser damage that occurs in the bulk and on the surface or the coating of optical components. It considers key issues in the field of hi

glaucoma proceedingings of the ophthalmological society of nigeria

African Journals Online (AJOL)

glaucoma is the second leading cause of blindness, accounting for 8% of blindness ... using Analyze-it V2.22 (2010) statistical software. Results: Four ..... software v 16. Results: Mean ages of all patients were 60.5 years. Mean laser power and shots used was 1535.4 mW and 47.9 (seeing eyes) and 1616.7. mW and 81.1 ...

Glaucoma and dry eye disease: the role of preservatives in glaucoma medications

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Ratna Sitompul

2011-11-01

Full Text Available Glaucoma is a common cause of irreversible blindness with increasing prevalence. Some of glaucoma patients will also experience dry eye. Dry eye is the most frequent side effect related to benzalkonium chloride (BAC-containing eye drop  used for glaucoma patients. In addition, glaucoma and dry eyes have shared risk factors that are old age and female. Dry eye among glaucoma patients need to be treated promptly as it produces discomfort, reduces patients’ compliance and   decreases success rate of glaucoma therapy. Dry eye symptoms can be treated by applying preservative-free eye drop, giving combination of preservative containing and preservative-free eye drop to reduce BAC exposure, prescribing artificial tear and conducting surgery to minimize or eliminate the need of topical medication. (Med J Indones 2011; 20:302-5Keywords: benzalkonium chloride, dry eye, glaucoma

Update on Minimally Invasive Glaucoma Surgery (MIGS and New Implants

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Lívia M. Brandão

2013-01-01

Full Text Available Traditional glaucoma surgery has been challenged by the advent of innovative techniques and new implants in the past few years. There is an increasing demand for safer glaucoma surgery offering patients a timely surgical solution in reducing intraocular pressure (IOP and improving their quality of life. The new procedures and devices aim to lower IOP with a higher safety profile than fistulating surgery (trabeculectomy/drainage tubes and are collectively termed “minimally invasive glaucoma surgery (MIGS.” The main advantage of MIGS is that they are nonpenetrating and/or bleb-independent procedures, thus avoiding the major complications of fistulating surgery related to blebs and hypotony. In this review, the clinical results of the latest techniques and devices are presented by their approach, ab interno (trabeculotomy, excimer laser trabeculotomy, trabecular microbypass, suprachoroidal shunt, and intracanalicular scaffold and ab externo (canaloplasty, Stegmann Canal Expander, suprachoroidal Gold microshunt. The drawback of MIGS is that some of these procedures produce a limited IOP reduction compared to trabeculectomy. Currently, MIGS is performed in glaucoma patients with early to moderate disease and preferably in combination with cataract surgery.

The treatment of malignant glaucoma in nanophthalmos: a case report.

Science.gov (United States)

Wang, Jie; Du, Ergang; Tang, Jinfei

2018-02-23

The management of eyes with nanophthalmos is a dilemma for ophthalmologists due to various complications, especial the eye with malignant glaucoma. We report a case of effective treatment for malignant glaucoma in nanophthalmos. An 82-year-old man was performed phacoemulsification in the right eye with normal ocular pressure and nanophthalmos. The surgery was uneventful: an intraocular lens (IOL) was placed and centered in the capsular bag. 2 months later, the patient presented with malignant glaucoma, and the intraocular pressure fluctuated between 18.6 mmHg and 30.8 mmHg with antiglaucoma medications. The patient did not respond to surgical peripheral iridotomy and goniosynechialysis. Then a single treatment with laser peripheral lens posterior capsulotomy and vitreous anterior membranectomy was performed. The intraocular pressure normalized, and the anterior chamber deepened within 24 h. The patient's condition remained stable for 9 months with no further treatment, and his Snellen corrected distance visual acuity was 20/50. The left eye of this patient was treated by combined surgery including phacoemulsification, IOL implantation, anterior vitrectomy, surgical peripheral iridotomy (PI), and goniosynechialysis. No intraoperative or postoperative complications were observed. This case suggests that it is essential to choose a suitable treatment for nanophthalmos patients to deal with malignant glaucoma and to reduce the incidence of malignant glaucoma.

Glaucoma Monitoring in a Clinical Setting Glaucoma Progression Analysis vs Nonparametric Progression Analysis in the Groningen Longitudinal Glaucoma Study

NARCIS (Netherlands)

Wesselink, Christiaan; Heeg, Govert P.; Jansonius, Nomdo M.

Objective: To compare prospectively 2 perimetric progression detection algorithms for glaucoma, the Early Manifest Glaucoma Trial algorithm (glaucoma progression analysis [GPA]) and a nonparametric algorithm applied to the mean deviation (MD) (nonparametric progression analysis [NPA]). Methods:

Normal-tension glaucoma (Low-tension glaucoma)

Science.gov (United States)

Anderson, Douglas R

2011-01-01

Glaucoma is now considered an abnormal physiology in the optic nerve head that interacts with the level of intraocular pressure (IOP), with the degree and rate of damage depending on the IOP and presumably the degree of abnormal physiology. Diagnosis of normal-tension glaucoma (NTG), defined as glaucoma without a clearly abnormal IOP, depends on recognizing symptoms and signs associated with optic nerve vulnerability, in addition to absence of other explanations for disc abnormality and visual field loss. Among the findings are a halo or crescent of absence of retinal pigment epithelium around the disc, bilateral pre-chiasmal visual field defects, splinter hemorrhages at the disc margin, vascular dysregulation (low blood pressure, cold hands and feet, migraine headache with aura, and the like), or a family history of glaucoma. Possibly relevant, is a history of hemodynamic crisis, arterial obstructive disease, or sleep apnea. Neurological evaluation with imaging is needed only for atypical cases or ones that progress unexpectedly. Management follows the same principle of other chronic glaucomas, to lower the IOP by a substantial amount, enough to prevent disabling visual loss. However, many NTG cases are non-progressive. Therefore, it may often be wisein mild cases to determine whether the case is progressive and the rate of progression before deciding on how aggressivene to be with therapy. Efforts at neuroprotection and improvement in blood flow have not yet been shown effective. PMID:21150042

Normal-tension glaucoma (Low-tension glaucoma

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Anderson Douglas

2011-12-01

Full Text Available Glaucoma is now considered an abnormal physiology in the optic nerve head that interacts with the level of intraocular pressure (IOP, with the degree and rate of damage depending on the IOP and presumably the degree of abnormal physiology. Diagnosis of normal-tension glaucoma (NTG, defined as glaucoma without a clearly abnormal IOP, depends on recognizing symptoms and signs associated with optic nerve vulnerability, in addition to absence of other explanations for disc abnormality and visual field loss. Among the findings are a halo or crescent of absence of retinal pigment epithelium around the disc, bilateral pre-chiasmal visual field defects, splinter hemorrhages at the disc margin, vascular dysregulation (low blood pressure, cold hands and feet, migraine headache with aura, and the like, or a family history of glaucoma. Possibly relevant, is a history of hemodynamic crisis, arterial obstructive disease, or sleep apnea. Neurological evaluation with imaging is needed only for atypical cases or ones that progress unexpectedly. Management follows the same principle of other chronic glaucomas, to lower the IOP by a substantial amount, enough to prevent disabling visual loss. However, many NTG cases are non-progressive. Therefore, it may often be wisein mild cases to determine whether the case is progressive and the rate of progression before deciding on how aggressivene to be with therapy. Efforts at neuroprotection and improvement in blood flow have not yet been shown effective.

Protective effects of triptolide on retinal ganglion cells in a rat model of chronic glaucoma

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Yang F

2015-11-01

Full Text Available Fan Yang, Dongmei Wang, Lingling Wu, Ying Li Ophthalmology Department, Peking University Third Hospital, Beijing, People’s Republic of China Purpose: To study the effects of triptolide, a Chinese herb extract, on retinal ganglion cells (RGCs in a rat model of chronic glaucoma.Methods: Eighty Wistar rats were randomly divided into triptolide group (n=40 and normal saline (NS group (n=40. Angle photocoagulation was used to establish the model of glaucoma, with right eye as laser treated eye and left eye as control eye. Triptolide group received triptolide intraperitoneally daily, while NS group received NS. Intraocular pressure (IOP, anti-CD11b immunofluorescent stain in retina and optic nerve, RGCs count with Nissel stain and microglia count with anti-CD11b immunofluorescence stain in retina flat mounts, retinal tumor necrosis factor (TNF-α mRNA detection by reverse transcription–polymerase chain reaction, and double immunofluorescent labeling with anti-TNF-α and anti-CD11b in retinal frozen section were performed.Results: Mean IOP of the laser treated eyes significantly increased 3 weeks after photocoagulation (P<0.05, with no statistical difference between the two groups (P>0.05. RGCs survival in the laser treated eyes was significantly improved in the triptolide group than the NS group (P<0.05. Microglia count in superficial retina of the laser treated eyes was significantly less in the triptolide group (30.40±4.90 than the NS group (35.06±7.59 (P<0.05. TNF-α mRNA expression in the retina of the laser treated eyes in the triptolide group decreased by 60% compared with that in the NS group (P<0.01. The double immunofluorescent labeling showed that TNF-α was mainly distributed around the microglia.Conclusion: Triptolide improved RGCs survival in this rat model of chronic glaucoma, which did not depend on IOP decrease but might be exerted by inhibiting microglia activities and reducing TNF-α secretion. Keywords: glaucoma, triptolide

虹膜切口氪激光预光凝在青光眼激光治疗中的临床研究%Clinical Research of Pre-photocoagulation of Iris Cut by Krypton Laser in Glaucoma Laser Treatment

Institute of Scientific and Technical Information of China (English)

张磊

2011-01-01

Objective To observe the effect of pre - photocoagulation iris by krypton laser in glaucoma laser treatment. Methods All 78 cases( 92 eyes )were grouped into A and B. Group A was treated by krypton laser peripheral iridoplasty( LPIP ), iris pre - photocoagulation and YAG laser peripheral iridectomy ( LPI ). Group B was only treated by LPIP and YAG LPI. After laser Treatment, IOP, visual acuity and iris haemorrhage were observed. Results The difference of IOP and iris haemorrhage between group A and group B was statistically significant( P ＜ 0.05 ). Conclusion The method of pre - thermocoagulation iris by krypton laser can reduce the complication of glaucoma laser treatment effectively.%目的 观察虹膜切口氪激光预光凝对青光眼激光治疗的影响.方法 将我院门诊需行激光治疗的青光眼患者78例(92只眼)随机分成A、B组.A组行虹膜氪激光周边成形+切口周围预光凝+YAG激光切开术.B组行虹膜氪激光周边成形+YAG激光切开术,治疗后观察两组的视力、眼压、虹膜出血等指标.结果 比较两组在治疗后眼压和虹膜出血等并发症情况的差异有统计学意义(P < 0.05).结论 氪激光虹膜切口预光凝可以有效地降低青光眼激光治疗后的并发症.

Genomic and post-genomic effects of anti-glaucoma drugs preservatives in trabecular meshwork

Energy Technology Data Exchange (ETDEWEB)

Izzotti, Alberto, E-mail: izzotti@unige.it [Mutagenesis Unit, IRCCS AOU San Martino – IST, Genova (Italy); Department of Health Sciences, University of Genoa, Via A. Pastore 1, 16132 Genoa (Italy); La Maestra, Sebastiano; Micale, Rosanna Tindara; Longobardi, Maria Grazia [Department of Health Sciences, University of Genoa, Via A. Pastore 1, 16132 Genoa (Italy); Saccà, Sergio Claudio [Ophthalmology Unit, IRCCS AOU San Martino-IST, Genova (Italy)

2015-02-15

Highlights: • Glaucoma drug preservatives induce DNA damage in trabecular meshwork cells. • Cellular alteration is related with the occurrence of activation of apoptosis through the intrinsic pathway. • Drug preservatives unable to induce cell damage are ineffective in killing bacteria. • Anti glaucoma drugs should be formulated as single-dose usage devoid of genotoxic preservatives. - Abstract: Oxidative stress plays an important role in glaucoma. Some preservatives of anti-glaucoma drugs, commonly used in glaucoma therapy, can prevent or induce oxidative stress in the trabecular meshwork. The aim of this study is to evaluate cellular and molecular damage induced in trabecular meshwork by preservatives contained in anti-glaucoma drugs. Cell viability (MTT test), DNA fragmentation (Comet test), oxidative DNA damage (8-oxo-dG), and gene expression (cDNA microarray) have been evaluated in trabecular meshwork specimens and in human trabecular meshwork cells treated with benzalkonium chloride, polyQuad, purite, and sofzia-like mixture. Moreover, antimicrobial effectiveness and safety of preservative contents in drugs was tested. In ex vivo experiments, benzalkonium chloride and polyQuad induced high level of DNA damage in trabecular meshwork specimens, while the effect of purite and sofzia were more attenuated. The level of DNA fragmentation induced by benzalkonium chloride was 2.4-fold higher in subjects older than 50 years than in younger subjects. Benzalkonium chloride, and polyQuad significantly increased oxidative DNA damage as compared to sham-treated specimens. Gene expression was altered by benzalkonium chloride, polyQuad, and purite but not by sofzia. In in vitro experiments, benzalkonium chloride and polyQuad dramatically decreased trabecular meshwork cell viability, increased DNA fragmentation, and altered gene expression. A lesser effect was also exerted by purite and sofzia. Genes targeted by these alterations included Fas and effector caspase-3

Outcomes of Ahmed valve surgery for refractory glaucoma in Dhahran, Saudi Arabia

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Tariq Alasbali

2015-06-01

Full Text Available AIM:To evaluate the outcomes of Ahmed glaucoma valve (AGV implantation surgery for refractory glaucoma.METHODS:This one-armed historical cohort study was conducted in 2011. Refractory glaucoma was defined as eyes with an intraocular pressure (IOP greater than 21 mm Hg with maximally tolerated glaucoma medications, failed surgeries, or both. For all eyes with refractory glaucoma that underwent AGV implantation, data were collected on IOP, the best corrected visual acuity (BCVA and glaucoma medications preoperatively and 4, 6, 12, 24 and 56wk postoperatively. Logarithm values of IOP were calculated and compared.RESULTS: The study group was comprised of 30 patients (30 eyes, 16 males and 14 females with refractory glaucoma. Mean preoperative IOP was 39.3±13.8 mm Hg. Postoperative mean IOP was 15.7±7.1 mm Hg, 19.6±12.8 mm Hg and 13.9±14.2 mm Hg at 12, 24 and 56wk respectively. BCVA was ≥ 6/60 in 11 eyes preoperatively, and five eyes had BCVA≥6/60 at 56wk postoperatively. Preoperatively, more than four medications were used to treat glaucoma in 21 eyes. At 12wk postoperatively, no medications were required to control IOP in 20 eyes. At 56wk postoperatively, at least one medication was required to control IOP in 10 eyes. Over the entire follow up period, four eyes were treated with yttrium aluminium garnet (YAG laser and 14 eyes required a second surgery. The AGV was removed in four eyes.CONCLUSION: AGV implantation reduced IOP and the number of medications required to control refractory glaucoma. However, there was a higher risk of decreased vision. Long-term follow up and prompt intervention are recommended.

The Advanced Glaucoma Intervention Study (AGIS): 9. Comparison of glaucoma outcomes in black and white patients within treatment groups.

Science.gov (United States)

2001-09-01

To compare in eyes of black and white patients the progression of glaucoma after failure of medical therapy and upon start of surgical intervention. Cohort study analysis of data from a randomized clinical trial. This multicenter study included open-angle glaucoma patients who had failed medical therapy: 451 eyes of 332 black patients, 325 eyes of 249 white patients. Eyes were randomly assigned to an argon laser trabeculoplasty (ALT)-trabeculectomy-trabeculectomy (ATT) sequence or a trabeculectomy-ALT-trabeculectomy (TAT) sequence; they had been followed for 7 to 11 years at database closure. Main outcome measures were decrease of visual field (DVF), sustained decrease of visual field (SDVF), decrease of visual acuity (DVA), sustained decrease of visual acuity (SDVA), and failure of first surgical glaucoma intervention. Statistical methods included logistic regression to obtain average adjusted black-white odds ratios for binary outcomes, and Cox regression to estimate adjusted black-white risk ratios for time-to-event outcomes. In the ATT sequence blacks were at lower risk than whites of failure of first intervention (ALT, RR = 0.68, P = 0.040). In the TAT sequence blacks were at higher risk than whites of failure of the first intervention (trabeculectomy, RR = 1.79, P = 0.033), of intraocular pressure > or =18 mm Hg (average OR = 1.41, P = 0.026), and of DVF (average OR = 1.78, P = 0.007). In both treatment sequences, the average number of prescribed medications was greater for blacks than whites (P < or = 0.002). The results support the hypothesis that after failure of medical therapy and upon initiation of surgical intervention, an initial intervention with trabeculectomy retards the progression of glaucoma more effectively in white than in black patients. The data provide a weak suggestion that an initial surgical intervention with ALT retards the progression of glaucoma more effectively in black than in white patients.

Prevalent practice patterns in glaucoma: Poll of Indian ophthalmologists at a national conference

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Nikhil Shreeram Choudhari

2016-01-01

Full Text Available Purpose: The aim of this study is to explore and compare the prevailing practice patterns in the diagnosis and management of glaucoma among subspecialists and general ophthalmologists in India. Materials and Methods: This is an interactive audience response system (ARS based poll of ophthalmologists attending the annual conference of the Glaucoma Society of India in 2013. Results: The information was obtained from 379 ophthalmologists (146 glaucoma specialists, 54 nonglaucoma subspecialists, and 179 general ophthalmologists. The majority of polled ophthalmologists (236; 62% had 10 or more years of experience in ophthalmology. The glaucoma specialists differed from nonglaucomatologists in their preference for Goldmann applanation tonometer (P < 0.01, four-mirror gonioscope (P < 0.01, Humphrey perimeter (P < 0.01, laser peripheral iridotomy in primary angle closure disease (P = 0.03, postiridotomy gonioscopy (P < 0.01, and usage of antifibrotic agents during filtering surgery (P < 0.01. Optical coherence tomography was the most preferred imaging modality and was utilized more often by the subspecialists than general ophthalmologists. The ophthalmologists also differed in their choice of antiglaucoma medications. More glaucoma specialists were performing surgery on children with congenital glaucoma (P < 0.01, implanting glaucoma drainage devices (P < 0.01, and using scientific journals to upgrade knowledge (P = 0.03 than the other ophthalmologists. Conclusions: This poll is the first of its kind in India, in its usage of the ARS, and in comparing the practice patterns of care for glaucoma among subspecialists and general ophthalmologists. It has revealed substantial diversity in a few areas among those who did and did not receive specialty training in glaucoma.

Double pulse laser ablation and plasma: Laser induced breakdown spectroscopy signal enhancement

International Nuclear Information System (INIS)

Babushok, V.I.; DeLucia, F.C.; Gottfried, J.L.; Munson, C.A.; Miziolek, A.W.

2006-01-01

A review of recent results of the studies of double laser pulse plasma and ablation for laser induced breakdown spectroscopy applications is presented. The double pulse laser induced breakdown spectroscopy configuration was suggested with the aim of overcoming the sensitivity shortcomings of the conventional single pulse laser induced breakdown spectroscopy technique. Several configurations have been suggested for the realization of the double pulse laser induced breakdown spectroscopy technique: collinear, orthogonal pre-spark, orthogonal pre-heating and dual pulse crossed beam modes. In addition, combinations of laser pulses with different wavelengths, different energies and durations were studied, thus providing flexibility in the choice of wavelength, pulse width, energy and pulse sequence. The double pulse laser induced breakdown spectroscopy approach provides a significant enhancement in the intensity of laser induced breakdown spectroscopy emission lines up to two orders of magnitude greater than a conventional single pulse laser induced breakdown spectroscopy. The double pulse technique leads to a better coupling of the laser beam with the plasma plume and target material, thus providing a more temporally effective energy delivery to the plasma and target. The experimental results demonstrate that the maximum effect is obtained at some optimum separation delay time between pulses. The optimum value of the interpulse delay depends on several factors, such as the target material, the energy level of excited states responsible for the emission, and the type of enhancement process considered. Depending on the specified parameter, the enhancement effects were observed on different time scales ranging from the picosecond time level (e.g., ion yield, ablation mass) up to the hundred microsecond level (e.g., increased emission intensity for laser induced breakdown spectroscopy of submerged metal target in water). Several suggestions have been proposed to explain

Trabeculectomy versus Ahmed Glaucoma Valve implantation in neovascular glaucoma

OpenAIRE

Netland, Peter; Shen,Chris; Salim,Sarwat; Du,Haiming

2011-01-01

Christopher C Shen1, Sarwat Salim2, Haiming Du2, Peter A Netland31Glaucoma Consultants Northwest, Seattle, WA, USA; 2University of Tennessee Health Science Center, Memphis, TN, USA; 3University of Virginia School of Medicine, Charlottesville, VA, USAPurpose: To compare surgical outcomes in neovascular glaucoma patients who underwent trabeculectomy with mitomycin C versus Ahmed Glaucoma Valve implantation. Patients and methods: This was a retrospective comparative case series. We reviewed 40 e...

High prevalence of narrow angles among Chinese-American glaucoma and glaucoma suspect patients.

Science.gov (United States)

Seider, Michael I; Pekmezci, Melike; Han, Ying; Sandhu, Simi; Kwok, Shiu Y; Lee, Roland Y; Lin, Shan C

2009-01-01

To evaluate the prevalence of gonioscopically narrow angles in a Chinese-American population with glaucoma or glaucoma suspicion. Charts from all Chinese-American patients seen in a comprehensive ophthalmology clinic in the Chinatown district of San Francisco in 2002 were reviewed. One eye from each patient with glaucoma or glaucoma suspicion that met inclusion criteria was included (n=108). Data were collected for sex, age, race (self-declared), refraction (spherical equivalent), intraocular pressure, gonioscopy, and vertical cup-to-disk ratio. Sixty percent (n=65) of Chinese-American eyes with glaucoma or glaucoma suspicion had gonioscopically narrow angles (Shaffer grade or = 0.071). In a multivariate model including age, sex, and refraction as predictors of angle grade (open or narrow), only age was a significant predictor of angle grade (P=0.004). A large proportion of Chinese-Americans in our study population with glaucoma or glaucoma suspicion had gonioscopically narrow angles. In multivariate analysis, patients with narrow angles were older than those with open angles but did not differ from them in terms of sex or refraction. Continued evaluation of angle closure glaucoma risk among Chinese-Americans is needed.

The use of Ahmed glaucoma valve in the management of pediatric glaucoma.

Science.gov (United States)

Balekudaru, Shantha; Vadalkar, Juhie; George, Ronnie; Vijaya, Lingam

2014-08-01

To assess the intraocular pressure control (IOP), changes in visual acuity, complications, reoperation rates and risk factors for failure following Ahmed glaucoma valve implantation in pediatric eyes with glaucoma. The medical records of consecutive patients with glaucoma who underwent Ahmed glaucoma valve implantation from January 2000 to December 2009) were retrospectively reviewed. Only one eye of each patient was included. Subgroup analysis was performed in three groups; group 1 included phakic eyes with primary congenital glaucoma, juvenile open-angle glaucoma, or glaucoma associated with ocular anomalies; group 2 included eyes with glaucoma in aphakia or pseudophakia; group 3 included eyes with other diagnoses. A successful outcome was defined as final IOP between 6 mm Hg and 18 mm Hg without loss of light perception or reoperation for glaucoma. A total of 71 eyes in 71 patients: 15 (21%) in group 1, 47 (66%) in group 2, and 9 (13%) in group 3 were included Successful IOP control was achieved in 44 eyes of 44 patients (62%). Cumulative probabilities of success by Kaplan-Meier analysis at 12 and 24 months was 97% and 80% for the entire group, 100% and 82% for group 1, 95% and 86% for group 2, and 90% and 42% for group 3. Reoperation was necessary for 18 patients (25%), either for tube-related complications or for IOP control. The only significant risk factor for failure was the category of diagnosis (P = 0.029). Ahmed glaucoma valve implantation is an option in the management of pediatric glaucoma; however, reoperations for tube related complications or for persistent elevated IOP is frequently needed. Copyright © 2014 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

Selective laser trabeculoplasty in patients with pseudoexfoliative glaucoma vs primary open angle glaucoma: a one-year comparative study

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Arezoo Miraftabi

2016-03-01

Full Text Available AIM: To compare the efficacy of single-session 360-degree selective laser trabeculoplasty (SLT for reduction of intraocular pressure (IOP in patients with pseudoexfoliative glaucoma (PXFG and primary open angle glaucoma (POAG. METHODS: This is a single-center, prospective, nonrandomized comparative study. Patients older than 18 years of age with uncontrolled PXFG or POAG eyes requiring additional therapy while on maximally tolerated IOP-lowering medications were included. The primary outcome measure changed in IOP from baseline. Success was defined as IOP reduction ≥20% from baseline without any additional IOP-lowering medication. All patients were examined at 1d, 1wk, 1, 3, 6, 9, 12mo after SLT. RESULTS: Nineteen patients (20 eyes with PXFG and 27 patients (28 eyes with POAG were included in the study. In the visual fields mean deviation was -2.88 (±1.67 in the POAG and -3.1 (±1.69 in the PXFG groups (P=0.3. The mean (±SD IOP was 22.9 (±3.7 mm Hg in the POAG group and 25.7 (±4.4 mm Hg in the PXFG group at baseline and decreased to 18.4 (±3.2 and 18.0 (±3.9 mm Hg in the POAG group (P<0.001 and P=0.02, and to 17.9 (±4.0 and 21.0 (±6.6 mm Hg in the PXFG group (P<0.001 and P=0.47 at 6 and 12mo, respectively. The number of medications was 2.6 (±0.8 in the POAG group and 2.5 (±0.8 in the PXFG group at baseline, and did not change at all follow-up visits in both groups (P=0.16 in POAG and 0.57 in PXFG. Based on Kaplan-Meier survival analysis, the success rate was 75% in the POAG group compared to 94.1% in the PXFG group (P=0.08; log rank test at 6mo, and 29.1% and 25.0% at 12mo, respectively (P=0.9; log rank. CONCLUSION: The 360-degree SLT is an effective and well-tolerated therapeutic modality in patients with POAG and PXFG by reducing IOP without any change in number of medications. The response was more pronounced early in the postoperative period in patients with PXFG whereas there was no statistically significant difference at 12

[Music and Glaucoma].

Science.gov (United States)

Plange, N

2017-02-01

Music may have multiple influences on the human organism. A possible therapeutic effect for patients with glaucoma has been postulated, aside from the known impact of music on the cardiovascular system, psychogenic effects and a short-term improvement in mental performance (Mozart effect). The higher level of mental stress in patients with glaucoma and type-A personality behaviour may be related to higher intraocular pressure in patients with glaucoma. Relaxing music may have a positive impact in these patients, related to a reduction in intraocular pressure or its fluctuations. However, only limited data exist on the effects of music on intraocular pressure. No clinical studies have yet been performed to investigate the effect of music or music therapy on glaucoma progression. The music of Mozart may influence visual field examinations, possibly due to a positive short term effect on mental performance. This factor needs to be addressed in studies dealing with the effect of music in glaucoma. The relevance of intraocular pressure increases in professional wind instrument players is controversial. An increased level of care might be advisable in patients with advanced glaucoma. The influences of music on humans, altered personality profiles in patients with glaucoma and the studies showing some effect of stress on intraocular pressure stress the relevance of psychological support for glaucoma patients, who are confronted with a disease with a high longterm risk of blindness. Georg Thieme Verlag KG Stuttgart · New York.

A Systematic Evaluation of State Laws Governing Optometric Glaucoma Management in the United States Upto 2015.

Science.gov (United States)

Chodnicki, Kevin; Kalarn, Sachin; Quinn, Laura; Jampel, Henry; Saeedi, Osamah

2018-03-01

To describe state laws that govern the optometric practice of glaucoma management in the United States and to correlate those laws with state demographics upto 2015. We performed a cross-sectional ecological study of the 50 United States and the District of Columbia. Regulations governing optometric scope of practice as written by each state Board of Optometry were reviewed. Specific optometric privileges assessed included: ability to manage glaucoma independently, use of diagnostic pharmaceutical agents, use of therapeutic pharmaceutical agents (including topical and oral steroids and other oral pharmaceutical agents), IV injections, intraocular injections, therapeutic lasers, presence of defined referral, and comanagement guidelines, and hours of yearly continuing education needed for glaucoma management. Optometric privilege was compared with demographic and employment information for each state. Optometrists in all states, except for Massachusetts, and the District of Columbia are allowed to manage glaucoma; 16 states have defined comanagement guidelines. Therapeutic lasers are allowed in 3 states: Kentucky, Louisiana, and Oklahoma. States with defined comanagement guidelines had a mean of 6.9±1.9 ophthalmologists per 100,000 people, significantly more than the 5.3±1.1 in states without defined comanagement of glaucoma (Pstate, the less likely there is to be defined comanagement [β (SE)=-0.008 (0.003), P=0.02] and the greater the number of ophthalmologists in a given state, the more likely a state has defined comanagement [β (SE)=-0.13 (0.006)]. There is a diversity of regulations that govern optometric management of glaucoma in each of the 50 states and the District of Columbia. The number of optometrists and ophthalmologists in a state may influence state regulations governing optometric practice and referral guidelines.

Glaucoma (image)

Science.gov (United States)

Glaucoma is a condition of increased fluid pressure inside the eye. The increased pressure causes compression of ... nerve which can eventually lead to nerve damage. Glaucoma can cause partial vision loss, with blindness as ...

Glaucoma Foundation

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... Options: SIZE CONTRAST Search Home About TGF About Glaucoma About Exfoliation Syndrome Research Center Contact Us Get ... tear glands, and a common preservative in many glaucoma medications can worsen the symptoms. The main treatment ...

[Long-term outcomes of Ahmed glaucoma valve implantation for treating refractory glaucoma].

Science.gov (United States)

Xu, Yumei; Hong, Tao; Li, Wanming

2015-02-10

To explore the efficacies and complications of Ahmed glaucoma valve implantation for treating refractory glaucoma. A retrospective study of case series was conducted for 24 patients (26 eyes) with refractory glaucoma from February 2001 to July 2008 at our hospital. Ahmed glaucoma valve implantation was performed. Pre- and post-operative best spectacle-corrected visual acuity (BSCVA), intraocular pressure (IOP), number of medications and complications were recorded and analyzed. The follow-up period was 58-159 months. The post-operative values of IOP were 13.02+/-6.79, 11.43+/-5.24 and 18.56+/-6.43 mmHg at 1 day, 1 month and the last follow-up respectively. There were significant difference when compared with pre-operative IOP (37.59+/-10.76 mmHg, P glaucoma drugs after glaucoma valve implantation and the average number of medication was 1.72+/-0.98. There was significant difference with the pre-operative medication number 2.7 ± 0.7 (P = 0.001). The surgical success rate was 73.1%. And the causes of failure were endophthalmitis, corneal endothelial decompensation, persistent conjunctival wound non-healing, glaucoma valve exposure and loss of light perception.Early postoperative complications were ocular hypotony, shallow anterior chamber, hyphema, transient high IOP and tube occlusion. And long-term complications included encapsulated cyst formation, tube exposure, corneal endothelial decompensation and endophthalmitis. Ahmed glaucoma valve implantation is efficacious for refractory glaucoma.However, clinicians should pay attention to the prevention and treatment of complications.

Femtosecond laser-induced herringbone patterns

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Garcell, Erik M.; Lam, Billy; Guo, Chunlei

2018-06-01

Femtosecond laser-induced herringbone patterns are formed on copper (Cu). These novel periodic structures are created following s-polarized, large incident angle, femtosecond laser pulses. Forming as slanted and axially symmetric laser-induced periodic surface structures along the side walls of ablated channels, the result is a series of v-shaped structures that resemble a herringbone pattern. Fluence mapping, incident angle studies, as well as polarization studies have been conducted and provide a clear understanding of this new structure.

Role of laser peripheral iridotomy in pigmentary glaucoma and pigment dispersion syndrome: A review of the literature.

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Buffault, J; Leray, B; Bouillot, A; Baudouin, C; Labbé, A

2017-11-01

Pigment dispersion syndrome (PDS) is characterized by a structural abnormality of the posterior surface of the iris causing contact with the zonular fibers. It can lead to an open-angle glaucoma secondary to pigment dispersion into the trabecular meshwork. Laser peripheral iridotomy (PI) has been proposed as a treatment for pigmentary glaucoma (PG) and pigment dispersion syndrome (PDS) by reducing the dispersion of pigment. The goal of this review was to assess the effects of PI for PDS and PG. We included six randomized controlled trials and two cohort studies (286 eyes of 218 participants). Four trials included participants with PG, and 4 trials enrolled participants with PDS with or without elevated intraocular pressure (IOP). Among patients with PG, at an average of 9 months of follow-up, the mean difference in IOP between groups was 2.69mm Hg less in the PI group (95% CI: -6.05 to 0.67; 14 eyes). In patients with PDS, the average IOP was statistically lower after PI as compared to baseline (Student test t=11.49, P<0.01, 38 eyes). With regard to visual field progression in participants with PG, after an average follow-up of 28 months, the risk of progression was not influenced by PI (RR 1.00 95% CI: 0.16 to 6.25; 32 eyes). No trials that enrolled patients with PDS showed a diminution of the risk of glaucoma conversion at mid- and long-terms. PI decreases the biomechanical factor causing contact between the iris and zonular fibers and may lower IOP over the long-term. Nevertheless, the effects of PI on visual field changes or progression have not been established in PG and PDS. There is no scientific evidence as of yet to advocate PI as a treatment for PDS or PG. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Development of a micro-mechanical valve in a novel glaucoma implant.

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Siewert, Stefan; Schultze, Christine; Schmidt, Wolfram; Hinze, Ulf; Chichkov, Boris; Wree, Andreas; Sternberg, Katrin; Allemann, Reto; Guthoff, Rudolf; Schmitz, Klaus-Peter

2012-10-01

This paper describes methods for design, manufacturing and characterization of a micro-mechanical valve for a novel glaucoma implant. The implant is designed to drain aqueous humour from the anterior chamber of the eye into the suprachoroidal space in case of an elevated intraocular pressure (IOP). In contrast to any existing glaucoma drainage device (GDD), the valve mechanism is located in the anterior chamber and there, surrounded by aqueous humour, immune to fibrosis induced failure. For the prevention of hypotony the micro-mechanical valve is designed to open if the physiological pressure difference between the anterior chamber and the suprachoroidal space in the range of 0.8 mmHg to 3.7 mmHg is exceeded. In particular the work includes: (i) manufacturing and morphological characterization of polymer tubing, (ii) mechanical material testing as basis for (iii) the design of micro-mechanical valves using finite element analysis (FEA), (iv) manufacturing of microstent prototypes including micro-mechanical valves by femtosecond laser micromachining and (v) the experimental fluid-mechanical characterization of the manufactured microstent prototypes with regard to valve opening pressure. The considered materials polyurethane (PUR) and silicone (SIL) exhibit low elastic modulus and high extensibility. The unique valve design enables a low opening pressure of micro-mechanical valves. An ideal valve design for PUR and SIL with an experimentally determined opening pressure of 2 mmHg and 3.7 mmHg is identified. The presented valve approach is suitable for the inhibition of hypotony as a major limitation of today's GDD and will potentially improve the minimally invasive treatment of glaucoma.

An Algorithm for Glaucoma Screening in Clinical Settings and Its Preliminary Performance Profile

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S-Farzad Mohammadi

2013-01-01

Full Text Available Purpose: To devise and evaluate a screening algorithm for glaucoma in clinical settings. Methods: Screening included examination of the optic disc for vertical cupping (≥0.4 and asymmetry (≥0.15, Goldmann applanation tonometry (≥21 mmHg, adjusted or unadjusted for central corneal thickness, and automated perimetry. In the diagnostic step, retinal nerve fiber layer imaging was performed using scanning laser polarimetry. Performance of the screening protocol was assessed in an eye hospital-based program in which 124 non-physician personnel aged 40 years or above were examined. A single ophthalmologist carried out the examinations and in equivocal cases, a glaucoma subspecialist′s opinion was sought. Results: Glaucoma was diagnosed in six cases (prevalence 4.8%; 95% confidence interval, 0.01-0.09 of whom five were new. The likelihood of making a definite diagnosis of glaucoma for those who were screened positively was 8.5 times higher than the estimated baseline risk for the reference population; the positive predictive value of the screening protocol was 30%. Screening excluded 80% of the initial population. Conclusion: Application of a formal screening protocol (such as our algorithm or its equivalent in clinical settings can be helpful in detecting new cases of glaucoma. Preliminary performance assessment of the algorithm showed its applicability and effectiveness in detecting glaucoma among subjects without any visual complaint.

[Visual development and amblyopia prophylaxis in pediatric glaucoma].

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Steffen, H

2011-07-01

In children with congenital glaucoma the functional long-term result is often disappointing even if the intraocular pressure is well controlled. The reason for this discrepancy is attributed to amblyogenic factors responsible for interfering with normal visual development. These amblyogenic factors are corneal edema, irregular astigmatism and non-corrected ametropia as monocular causes. Binocular causes are anisometropia-induced suppression and strabismus. Full ametropic correction and a very early prophylaxis and treatment of amblyopia with a close follow-up are mandatory to reduce amblyogenic visual impairment in children with congenital glaucoma.

Glaucoma: Symptoms, Diagnosis & Treatment

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... of this page please turn JavaScript on. Feature: Glaucoma Symptoms, Treatment and Research Past Issues / Spring 2015 ... vision, without any pain. Photo courtesy of NEI Glaucoma Symptoms At first, open-angle glaucoma has no ...

Angle observation of laser peripheral iridoplasty for the treatment of acute angle-closure glaucoma which could not be controlled by drugs

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Wei Han

2013-07-01

Full Text Available AIM: To evaluate the effect of laser peripheral iridoplasty(LPIPto treat acute angle-closure glaucoma(AACGwhich could not controlled by drugs and with persistent ocular hypertension. METHODS: Totally 67 patients(69 eyeswith AACG were performed LPIP when intraocular pressure(IOPwas still over 30mmHg after the medicine therapy for 3-6 hours. Visual acuity and intraocular pressure were under detection before laser treatment and 30 minutes, 60 minutes and 2 hours after laser treatment. We measured the anterior chamber depth, width of angle, iris thickness with ultrasound biomicroscope(UBM. Dynamic gonioscopy was used to evaluate the degree of peripheral anterior synechia(PAS.RESULTS: Angle open distance(AODafter iridoplasty was increased(PPF=151.79, PCONCLUSION: LPIP can deepen peripheral anterior chamber, increase the angle access and lower the IOP immediately. It is an important ongoing adjuvant treatment, which can reduce the patients suffering by lowering the IOP quickly, reduce the damage of visual function caused by long-term high intraocular pressure, avoid side effect of the drugs, and can improve the prognosis.

Get Tested for Glaucoma!

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... of this page please turn Javascript on. Feature: Glaucoma Get Tested for Glaucoma! Past Issues / Fall 2009 Table of Contents Taylor ... aoa.org/ When were you finally diagnosed with glaucoma? Not until 1969, after a game of basketball. ...

Prevalence of open angle glaucoma in accompanying first degree relatives of patients with glaucoma

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Franciele Vegini

2008-01-01

Full Text Available OBJECTIVE: The aim of this study was to determine the prevalence of open angle glaucoma in first-degree relatives accompanying POAG patients during routine examination in a reference hospital. METHOD: First-degree relatives of primary open angle glaucoma patients who accompanied their relatives to the glaucoma service of a reference hospital were screened for glaucoma. RESULTS: One-hundred and one first-degree relatives were examined, of which 56.4% had never had their intraocular pressure measured. 10.9% had previously been diagnosed with glaucoma, and 5.9% were newly diagnosed during this study. CONCLUSIONS: The eye examination of first-degree relatives identified a significant percentage of individuals with glaucoma. Despite being first-degree relatives of glaucoma patients, 56.4% of the companions had never had their eye pressure measured, demonstrating a lack of awareness about this disease.

Trans-scleral selective laser trabeculoplasty (SLT) without a gonioscopy lens (Conference Presentation)

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Belkin, Michael; Geffen, Noa; Goldenfeld, Modi; Ofir, Shay; Belkin, Avner; Assia, Ehud

2016-03-01

Developing a one-second automatic glaucoma treatment using trans-scleral laser trabeculoplasty (LTP) without a gonioscopy lens Purpose: Developing an LTP device for delivering multiple simultaneous trans-scleral applications of low energy laser irradiation to the trabecular meshwork (TM) for reducing Intraocular Pressure (IOP). Methods: Concept proof: A randomized, masked, controlled one was performed on open angle glaucoma patients. The control group underwent conventional SLT (100 laser spots through a gonioscope for 360 degrees directly on the TM). The trial group underwent irradiation by the same laser at the same irradiation parameters on the sclera overlying the TM. Topical glaucoma therapy was not changed during the 12 months trial. Feasibility trial: Using optimized laser parameters, 60 discrete applications were administered on similar locations of patients' sclera. Results: Concept proof: Trans-scleral applications: (N=15), IOP decrease from 20.21 mmHg before treatment to 16.00 (27.1%) at one year. The corresponding numbers for the control group (n=15), were 21.14 mmHg and 14.30 (23.4%). There was no statistical difference between the two groups in IOP reduction. The complications rate was significantly higher in the control group. Trial 2: IOP was reduced from an of 25.3 mmHg to 19.3 (23.7%) in the 11 patients. Conclusions: Laser coherency, lost in tissue transmission, is not required for the therapeutic effect. The new method will possibly enable treatment of angle closure glaucoma as well as simultaneous applications of all laser spots to the sclera. When used conjointly with target acquisition, will make feasible an automatic glaucoma treatment in less than one second.

Modeling Glaucoma: Retinal Ganglion Cells Generated from Induced Pluripotent Stem Cells of Patients with SIX6 Risk Allele Show Developmental Abnormalities.

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Teotia, Pooja; Van Hook, Matthew J; Wichman, Christopher S; Allingham, R Rand; Hauser, Michael A; Ahmad, Iqbal

2017-11-01

Glaucoma represents a group of multifactorial diseases with a unifying pathology of progressive retinal ganglion cell (RGC) degeneration, causing irreversible vision loss. To test the hypothesis that RGCs are intrinsically vulnerable in glaucoma, we have developed an in vitro model using the SIX6 risk allele carrying glaucoma patient-specific induced pluripotent stem cells (iPSCs) for generating functional RGCs. Here, we demonstrate that the efficiency of RGC generation by SIX6 risk allele iPSCs is significantly lower than iPSCs-derived from healthy, age- and sex-matched controls. The decrease in the number of RGC generation is accompanied by repressed developmental expression of RGC regulatory genes. The SIX6 risk allele RGCs display short and simple neurites, reduced expression of guidance molecules, and immature electrophysiological signature. In addition, these cells have higher expression of glaucoma-associated genes, CDKN2A and CDKN2B, suggesting an early onset of the disease phenotype. Consistent with the developmental abnormalities, the SIX6 risk allele RGCs display global dysregulation of genes which map on developmentally relevant biological processes for RGC differentiation and signaling pathways such as mammalian target of rapamycin that integrate diverse functions for differentiation, metabolism, and survival. The results suggest that SIX6 influences different stages of RGC differentiation and their survival; therefore, alteration in SIX6 function due to the risk allele may lead to cellular and molecular abnormalities. These abnormalities, if carried into adulthood, may make RGCs vulnerable in glaucoma. Stem Cells 2017;35:2239-2252. © 2017 AlphaMed Press.

Glaucoma as a Metabolic Optic Neuropathy: Making the Case for Nicotinamide Treatment in Glaucoma.

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Williams, Pete A; Harder, Jeffrey M; John, Simon W M

2017-12-01

Mitochondrial dysfunction may be an important, if not essential, component of human glaucoma. Using transcriptomics followed by molecular and neurobiological techniques, we have recently demonstrated that mitochondrial dysfunction within retinal ganglion cells is an early feature in the DBA/2J mouse model of inherited glaucoma. Guided by these findings, we discovered that the retinal level of nicotinamide adenine dinucleotide (NAD, a key molecule for mitochondrial health) declines in an age-dependent manner. We hypothesized that this decline in NAD renders retinal ganglion cells susceptible to damage during periods of elevated intraocular pressure. To replete NAD levels in this glaucoma, we administered nicotinamide (the amide of vitamin B3). At the lowest dose tested, nicotinamide robustly protected from glaucoma (~70% of eyes had no detectable glaucomatous neurodegeneration). At this dose, nicotinamide had no influence on intraocular pressure and so its effect was neuroprotective. At the highest dose tested, 93% of eyes had no detectable glaucoma. This represents a ~10-fold decrease in the risk of developing glaucoma. At this dose, intraocular pressure still became elevated but there was a reduction in the degree of elevation showing an additional benefit. Thus, nicotinamide is unexpectedly potent at preventing this glaucoma and is an attractive option for glaucoma therapeutics. Our findings demonstrate the promise for both preventing and treating glaucoma by interventions that bolster metabolism during increasing age and during periods of elevated intraocular pressure. Nicotinamide prevents age-related declines in NAD (a decline that occurs in different genetic contexts and species). NAD precursors are reported to protect from a variety of neurodegenerative conditions. Thus, nicotinamide may provide a much needed neuroprotective treatment against human glaucoma. This manuscript summarizes human data implicating mitochondria in glaucoma, and argues for studies to

Cost-effectiveness analysis of iStent trabecular microbypass stent for patients with open-angle glaucoma in Colombia

OpenAIRE

Osorio, Urpy; Ordoñez, Angelica

2018-01-01

Objective: To estimate cost-effectiveness of trabecular micro bypass stent versus laser trabeculoplasty or medications only, for patients with open-angle glaucoma in setting of Colombian System Health. Methods: This is a cost-effectiveness analysis that based its assumptions in external data sources, used to extrapolate the quality of life related to health, survival and costs. A Markov model, with stages from 0 (ocular hypertension without glaucoma) to 5 and bilateral blindness, was develope...

High Prevalence of Narrow Angles among Chinese-American Glaucoma and Glaucoma Suspect Patients

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Seider, Michael I; Pekmezci, Melike; Han, Ying; Sandhu, Simi; Kwok, Shiu Y; Lee, Roland Y; Lin, Shan C

2009-01-01

Purpose To evaluate the prevalence of gonioscopically narrow angles in a Chinese-American population with glaucoma or glaucoma suspicion. Patients and Methods Charts from all Chinese-American patients seen in a comprehensive ophthalmology clinic in the Chinatown district of San Francisco in 2002 were reviewed. One eye from each patient with glaucoma or glaucoma suspicion that met inclusion criteria was included (n=108). Data was collected for gender, age, race (self-declared), refraction (spherical equivalent), intraocular pressure (IOP), gonioscopy and vertical cup-to-disk ratio (CDR). Results Sixty percent (n=65) of Chinese-American eyes with glaucoma or glaucoma suspicion had gonioscopically narrow angles (Shaffer grade ≤2 in three or more quadrants). Those with narrow angles were significantly older (P=0.004) than their open angle counterparts, but the two groups did not differ in terms of gender, refraction, IOP or CDR (all, P≥0.071). In a multivariate model including age, gender and refraction as predictors of angle grade (open or narrow), only age was a significant predictor of angle grade (P=0.004). Conclusions A large proportion of Chinese-Americans in our study population with glaucoma or glaucoma suspicion had gonioscopically narrow angles. In multivariate analysis, patients with narrow angles were older than those with open angles but did not differ from them in terms of gender or refraction. Continued evaluation of angle closure glaucoma risk among Chinese-Americans is needed. PMID:19826385

Glaucoma: Hot Topics in Pharmacology.

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Balendra, Shiama I; Shah, Parth Arvind; Jain, Mishank; Grzybowski, Andrzej; Cordeiro, Maria F

2017-01-01

Glaucoma comprises a group of neurodegenerative diseases resulting in retinal ganglion cell death within the optic nerve head. It is projected to affect almost 80 million people worldwide by 2020. The condition's asymptomatic nature translates to over half of glaucoma sufferers being unaware of their condition. By the time of diagnosis, irreversible blindness is likely to have occurred. Prime areas of glaucoma research therefore include identification and optimization of risk factors for the disease, accurate and early diagnostic tools and novel therapeutic methods. The goal of this review was to summarize main areas of latest glaucoma research into risk factors of glaucoma, diagnostic tools and treatments. PubMed was used to search for terms including glaucoma risk factors, glaucoma diagnostics, glaucoma treatment, glaucoma drug delivery and glaucoma IOP. The evidence for risk factors of low CSF pressure, IOP, smoking, vascular risk factors and light toxicity is described. Latest diagnostic and monitoring techniques for glaucoma include SD-OCT, DARC and IOP telemetry. Current and emerging medical and surgical treatments in glaucoma are discussed. Rho kinase inhibitors have the potential to both lower IOP and also provide neuroprotection, several of which are in clinical trials. Several other new medical treatments such as calcium channel blockers and neurotrophic agents also have the capacity to provide neuroprotection. Minimally Invasive Glaucoma Surgery (MIGS) devices provide an improved safety profile compared to traditional trabeculectomy; the latest ab interno and ab externo devices are described. Novel drug delivery methods, including punctual plugs and contact lenses, help overcome the challenges with patient adherence. The ultimate goals are to reduce the individual patient risk factors associated with glaucoma, diagnose the condition early and to find treatments that not only reduce IOP but also reverse neurodegeneration of RGCs. The usage of combinations

Laser induced nuclear reactions

International Nuclear Information System (INIS)

Ledingham, Ken; McCanny, Tom; Graham, Paul; Fang Xiao; Singhal, Ravi; Magill, Joe; Creswell, Alan; Sanderson, David; Allott, Ric; Neely, David; Norreys, Peter; Santala, Marko; Zepf, Matthew; Watts, Ian; Clark, Eugene; Krushelnick, Karl; Tatarakis, Michael; Dangor, Bucker; Machecek, Antonin; Wark, Justin

1998-01-01

Dramatic improvements in laser technology since 1984 have revolutionised high power laser technology. Application of chirped-pulse amplification techniques has resulted in laser intensities in excess of 10 19 W/cm 2 . In the mid to late eighties, C. K. Rhodes and K. Boyer discussed the possibility of shining laser light of this intensity onto solid surfaces and to cause nuclear transitions. In particular, irradiation of a uranium target could induce electro- and photofission in the focal region of the laser. In this paper it is shown that μCi of 62 Cu can be generated via the (γ,n) reaction by a laser with an intensity of about 10 19 Wcm -2

A Naturally Fluorescent Mgp Transgenic Mouse for Angiogenesis and Glaucoma Longitudinal Studies.

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Asokan, Priyadarsini; Mitra, Rajendra N; Periasamy, Ramesh; Han, Zongchao; Borrás, Teresa

2018-02-01

Our goal was to generate and characterize a new mouse model in which only angiogenesis- and glaucoma-relevant tissues would be naturally fluorescent. The Matrix Gla (MGP) gene is highly expressed in vascular smooth muscle cells (VSMC) and trabecular meshwork (TM). We sought to direct our Mgp-Cre.KI mouse recombinase to VSMC/TM cells to produce their longitudinal fluorescent profiles. Homozygous Mgp-Cre.KI mice were crossed with Ai9 homozygous reporter mice harboring a loxP-flanked STOP cassette preventing transcription of a DsRed fluorescent protein (tdTomato). The F1 double-heterozygous (Mgp-tdTomato) was examined by direct fluorescence, whole mount, histology, and fundus photography. Custom-made filters had 554/23 emission and 609/54 exciter nanometer wavelengths. Proof of concept of the model's usefulness was conducted by inducing guided imaging laser burns. Evaluation of a vessel's leakage and proliferation was followed by noninvasive angiography. The Mgp-tdTomato mouse was viable, fertile, with normal IOP and ERG. Its phenotype exhibited red paws and snout (cartilage expression), which precluded genotyping. A fluorescent red ring was seen at the limbus and confirmed to be TM expression by histology. The entire retinal vasculature was red fluorescent (VSMC) and directly visualized by fundus photography. Laser burns on the Mgp-tdTomato allowed separation of leakiness and neovascularization evaluation parameters. The availability of a transgenic mouse naturally fluorescent in glaucoma-relevant tissues and retinal vasculature brings the unique opportunity to study a wide spectrum of single and combined glaucomatous conditions in vivo. Moreover, the Mgp-tdTomato mouse provides a new tool to study mechanisms and therapeutics of retinal angiogenesis longitudinally.

A Naturally Fluorescent Mgp Transgenic Mouse for Angiogenesis and Glaucoma Longitudinal Studies

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Asokan, Priyadarsini; Mitra, Rajendra N.; Periasamy, Ramesh; Han, Zongchao

2018-01-01

Purpose Our goal was to generate and characterize a new mouse model in which only angiogenesis- and glaucoma-relevant tissues would be naturally fluorescent. The Matrix Gla (MGP) gene is highly expressed in vascular smooth muscle cells (VSMC) and trabecular meshwork (TM). We sought to direct our Mgp-Cre.KI mouse recombinase to VSMC/TM cells to produce their longitudinal fluorescent profiles. Methods Homozygous Mgp-Cre.KI mice were crossed with Ai9 homozygous reporter mice harboring a loxP-flanked STOP cassette preventing transcription of a DsRed fluorescent protein (tdTomato). The F1 double-heterozygous (Mgp-tdTomato) was examined by direct fluorescence, whole mount, histology, and fundus photography. Custom-made filters had 554/23 emission and 609/54 exciter nanometer wavelengths. Proof of concept of the model's usefulness was conducted by inducing guided imaging laser burns. Evaluation of a vessel's leakage and proliferation was followed by noninvasive angiography. Results The Mgp-tdTomato mouse was viable, fertile, with normal IOP and ERG. Its phenotype exhibited red paws and snout (cartilage expression), which precluded genotyping. A fluorescent red ring was seen at the limbus and confirmed to be TM expression by histology. The entire retinal vasculature was red fluorescent (VSMC) and directly visualized by fundus photography. Laser burns on the Mgp-tdTomato allowed separation of leakiness and neovascularization evaluation parameters. Conclusions The availability of a transgenic mouse naturally fluorescent in glaucoma-relevant tissues and retinal vasculature brings the unique opportunity to study a wide spectrum of single and combined glaucomatous conditions in vivo. Moreover, the Mgp-tdTomato mouse provides a new tool to study mechanisms and therapeutics of retinal angiogenesis longitudinally. PMID:29392320

Ceratoplastia penetrante e glaucoma Penetrating keratoplasty and glaucoma

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Márcio Eulálio Barreto Soares

2007-08-01

Full Text Available O objetivo deste artigo é discutir os conhecimentos atuais sobre a abordagem clínica e terapêutica da ceratoplastia penetrante e do glaucoma a ela associado.The aim of this article is to make a review about glaucoma associated with penetrating keratoplasty, describing since its incidence and risk factors until the different options for treatment.

Screening for Glaucoma

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Understanding Task Force Recommendations Screening for Glaucoma The U.S. Preventive Services Task Force (Task Force) has issued a final recommendation statement on Screening for Glaucoma . This final recommendation statement ...

Laser iridotomy to treat uveitis-glaucoma-hyphema syndrome secondary to reverse pupillary block in sulcus-placed intraocular lenses: Case series.

Science.gov (United States)

Singh, Harmanjit; Modabber, Milad; Safran, Steven G; Ahmed, Iqbal Ike K

2015-10-01

To present cases of uveitis-glaucoma-hyphema (UGH) syndrome due to reverse pupillary block in sulcus-placed posterior chamber intraocular lenses (PC IOLs) that were managed with laser peripheral iridotomy (LPI). Community-based subspecialty clinics. Retrospective interventional case series. A chart review of patients with a sulcus-placed PC IOLs presenting with UGH syndrome and reverse pupillary block with posterior iris bowing as diagnosed by gonioscopy and anterior segment optical coherence tomography was carried out. Laser peripheral iridotomy was performed in the eyes included in the study. The main outcome measure was clinical resolution of UGH syndrome. The study included 6 eyes of 6 patients with a mean age of 59.8 years (range 43.0 to 66.0 years) who presented with unilateral UGH syndrome a mean of 28.7 months (range 0.3 to 84.0 months) after PC IOL implantation. All patients were previously myopic, with 5 (83.3%) having a history of vitrectomy. The mean axial length was 27.0 mm ± 1.4 (SD). An LPI was used to treat the reverse pupillary block with resultant improvement in iris profile and resolution of UGH syndrome in all eyes. The mean intraocular pressure decreased from 30.5 ± 10.0 mm Hg on 0.5 ± 0.8 glaucoma medications to 15.5 ± 3.2 mm Hg postoperatively on 0.7 ± 1.2 medications. The UGH syndrome due to reverse pupillary block occurred after sulcus-placed PC IOLs in susceptible patients, those with axial myopia, and post-vitrectomized eyes. The cases were managed with LPIs. Dr. Ahmed is a consultant to Alcon Laboratories, Inc. and Abbott Medical Optics, Inc. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Effect of laser pulse energies in laser induced breakdown spectroscopy in double-pulse configuration

International Nuclear Information System (INIS)

Benedetti, P.A.; Cristoforetti, G.; Legnaioli, S.; Palleschi, V.; Pardini, L.; Salvetti, A.; Tognoni, E.

2005-01-01

In this paper, the effect of laser pulse energy on double-pulse laser induced breakdown spectroscopy signal is studied. In particular, the energy of the first pulse has been changed, while the second pulse energy is held fixed. A systematic study of the laser induced breakdown spectroscopy signal dependence on the interpulse delay is performed, and the results are compared with the ones obtained with a single laser pulse of energy corresponding to the sum of the two pulses. At the same time, the crater formed at the target surface is studied by video-confocal microscopy, and the variation in crater dimensions is correlated to the enhancement of the laser induced breakdown spectroscopy signal. The results obtained are consistent with the interpretation of the double-pulse laser induced breakdown spectroscopy signal enhancement in terms of the changes in ambient gas pressure produced by the shock wave induced by the first laser pulse

Optical Coherence Tomography Angiography Vessel Density in Healthy, Glaucoma Suspect, and Glaucoma Eyes

Science.gov (United States)

Yarmohammadi, Adeleh; Zangwill, Linda M.; Diniz-Filho, Alberto; Suh, Min Hee; Manalastas, Patricia Isabel; Fatehee, Naeem; Yousefi, Siamak; Belghith, Akram; Saunders, Luke J.; Medeiros, Felipe A.; Huang, David; Weinreb, Robert N.

2016-01-01

Purpose The purpose of this study was to compare retinal nerve fiber layer (RNFL) thickness and optical coherence tomography angiography (OCT-A) retinal vasculature measurements in healthy, glaucoma suspect, and glaucoma patients. Methods Two hundred sixty-one eyes of 164 healthy, glaucoma suspect, and open-angle glaucoma (OAG) participants from the Diagnostic Innovations in Glaucoma Study with good quality OCT-A images were included. Retinal vasculature information was summarized as a vessel density map and as vessel density (%), which is the proportion of flowing vessel area over the total area evaluated. Two vessel density measurements extracted from the RNFL were analyzed: (1) circumpapillary vessel density (cpVD) measured in a 750-μm-wide elliptical annulus around the disc and (2) whole image vessel density (wiVD) measured over the entire image. Areas under the receiver operating characteristic curves (AUROC) were used to evaluate diagnostic accuracy. Results Age-adjusted mean vessel density was significantly lower in OAG eyes compared with glaucoma suspects and healthy eyes. (cpVD: 55.1 ± 7%, 60.3 ± 5%, and 64.2 ± 3%, respectively; P glaucoma and healthy eyes, the age-adjusted AUROC was highest for wiVD (0.94), followed by RNFL thickness (0.92) and cpVD (0.83). The AUROCs for differentiating between healthy and glaucoma suspect eyes were highest for wiVD (0.70), followed by cpVD (0.65) and RNFL thickness (0.65). Conclusions Optical coherence tomography angiography vessel density had similar diagnostic accuracy to RNFL thickness measurements for differentiating between healthy and glaucoma eyes. These results suggest that OCT-A measurements reflect damage to tissues relevant to the pathophysiology of OAG. PMID:27409505

Glaucoma: Screening Can Save Your Sight!

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... of this page please turn Javascript on. Feature: Glaucoma Glaucoma: Screening Can Save Your Sight! Past Issues / Fall 2009 Table of Contents People with glaucoma see the world through a tunnel. Glaucoma is ...

The glaucoma research foundation patient survey: patient understanding of glaucoma and its treatment.

Science.gov (United States)

Herndon, Leon W; Brunner, Thomas M; Rollins, Jane Neff

2006-01-01

Determine patients' understanding of glaucoma and its treatment, their sources of information about glaucoma, their preferences for treatment, their experience with medication side effects, and their reasons for changing eye doctors. Prospective, nonrandomized patient survey study. A questionnaire was developed and sent to the 22,000 subscribers of the Gleams newsletter who have glaucoma. Questionnaires were returned by 4310 glaucoma patients. Most respondents received glaucoma information from their eye doctor. Only 28% of respondents reported having changed eye doctors for reasons related to their glaucoma. Of those who had, 60% cited poor communication as the reason. When queried about specific side effects associated with their medication, over 85% of responding patients were never or rarely bothered by headaches and eyelid darkening. Most respondents (67% and 55%, respectively) were rarely or never disturbed by red eye or burning and stinging. Most respondents understood the importance of intraocular pressure (IOP) lowering in glaucoma, and of those patients who expressed a preference, 92% reported that they would prefer the medication that lowers IOP the most, even if it caused red eye for a few weeks, over a medication that caused no red eye but did not get IOP as low. Patients who subscribe to Gleams and responded to the survey rely most on their doctors for information about glaucoma and its treatment. Most understand the importance of maintaining low IOP to decrease the risk of vision loss, and most will tolerate temporary ocular side effects to achieve low IOP.

A prospective comparative study on neovascular glaucoma and non-neovascular refractory glaucoma following Ahmed glaucoma valve implantation.

Science.gov (United States)

Li, Zheng; Zhou, Minwen; Wang, Wei; Huang, Wenbin; Chen, Shida; Li, Xingyi; Gao, Xinbo; Zhang, Xiulan

2014-01-01

Neovascular glaucoma is a refractory disease, and difficult to manage. The aim of this study was to evaluate the clinical outcomes of Ahmed glaucoma valve implantation (AGVI) in neovascular glaucoma (NVG) and non-NVG patients. This prospective, non-randomized study included 55 eyes of 55 patients with refractory glaucoma; 27 had NVG (NVG group) and 28 had non-NVG (non-NVG group). All of the patients underwent AGVI. The NVG group was adjunctively injected with intravitreal ranibizumab/bevacizumab (IVR/IVB) before AGVI. Intraocular pressure (IOP) was the primary outcome measure in this study. Surgical success rate, number of antiglaucoma medications used, best corrected visual acuity (BCVA), and postoperative complications were analyzed between the groups. All of the patients completed the study (follow-up of 12 months). Kaplan-Meier survival curve analysis indicated that the qualified success rates in the NVG and non-NVG groups at 12 months were 70.5% and 92.9%, respectively; this difference was significant (P = 0.036). The complete success rates in the NVG and non-NVG groups at 12 months were 66.7% and 89.3%, respectively (P = 0.049). Compared with preoperative examinations, the postoperative mean IOP and use of medications were significantly lower at all follow-up time points in both groups (all P glaucoma, but the success rate of surgery was related to the type of refractory glaucoma. The complete and qualified success rates of NVG patient adjunctive anti-vascular endothelial growth factor treatment are still lower than those of non-NVG patients.

Efficacy of intravitreal ranibizumab combined with Ahmed glaucoma valve implantation for the treatment of neovascular glaucoma.

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Tang, Min; Fu, Yang; Wang, Ying; Zheng, Zhi; Fan, Ying; Sun, Xiaodong; Xu, Xun

2016-01-09

Neovascular glaucoma is a refractive glaucoma. Recently, anti-VEGF factors have been used alone or in combination for the treatment of neovascular glaucoma. However, the medium- and long-term efficacy of such drugs remains to be evaluated. This study was to determine the efficacy of intravitreal ranibizumab combined with Ahmed glaucoma valve implantation for the treatment of neovascular glaucoma. In this prospective non-randomized study, 43 neovascular glaucoma patients (43 eyes) were assigned to receive either 0.5 mg intravitreal ranibizumab for three to 14 days before Ahmed glaucoma valve implantation (injection group, n = 21) or Ahmed glaucoma valve implantation alone (control group, n = 22). The patients were followed up for six to 12 months. Differences in surgical success rate, intraocular pressure, best corrected visual acuity, anti-glaucoma medications and postoperative complications were compared between the two groups. Surgical success was defined as IOP > = 6 mm Hg and glaucoma medications, and without severe complications or reoperation. Of the 43 patients, 40 completed the 6-month follow-up and 37 completed the 1-year follow-up. Success rate was 73.7% vs. 71.4% at six months and 72.2% vs. 68.4% at 12 months in the injection group and the control group respectively. No significant difference was noted between the two groups (six months: P = 0.87, 12 months: P = 1.00). There were no significant differences in the two groups with respect to intraocular pressure, best corrected visual acuity, anti-glaucoma medications or postoperative complications at six months or 12 months. Single intravitreal ranibizumab (0.5 mg) before surgery has no significant effect on the medium- or long-term outcomes of neovascular glaucoma treated with Ahmed glaucoma valve implantation. Chinese Clinical Trial Registry ( ChiCTR-OOC-14005709, Trial registration date: 2014-12-01).

Evaluation of ExPress glaucoma filtration device in Indian patients with advanced glaucoma

OpenAIRE

Angmo, Dewang; Sharma, Reetika; Temkar, Shreyas; Dada, Tanuj

2015-01-01

ExPress glaucoma filtration device (GFD) has recently become available in India as a surgical option for glaucoma patients. We retrospectively evaluated the outcome of ExPress GFD in 12 eyes with advanced glaucoma with intraocular pressures (IOPs) not controlled on maximal tolerable medical therapy. The mean preoperative IOP of 29.58 ± 7.13 mmHg decreased to 17.0 ± 2.67 and 17.40 ± 0.89 mmHg at 6 and 12 months after surgery. Absolute success (IOP ≤ 18 mmHg, with no additional glaucoma medicat...

microRNA-21a-5p/PDCD4 axis regulates mesenchymal stem cell-induced neuroprotection in acute glaucoma.

Science.gov (United States)

Su, Wenru; Li, Zuohong; Jia, Y; Zhu, Yingting; Cai, Wenjia; Wan, Peixing; Zhang, Yingying; Zheng, Song Guo; Zhuo, Yehong

2017-08-01

Mesenchymal stem cells (MSCs) have been demonstrated to have promising therapeutic benefits for a variety of neurological diseases; however, the underlying mechanisms are poorly understood. Here, we showed that intravitreal infusion of MSCs promoted retinal ganglion cell (RGC) survival in a mouse model of acute glaucoma, with significant inhibition of microglial activation, production of TNF-α, IL-1β, and reactive oxygen species, as well as caspase-8 and caspase-3 activation. In vitro, MSCs inhibited both caspase-8-mediated RGC apoptosis and microglial activation, partly via the action of stanniocalcin 1 (STC1). Furthermore, we found that microRNA-21a-5p (miR-21) and its target, PDCD4, were essential for STC1 production and the neuroprotective property of MSCs in vitro and in vivo. Importantly, miR-21 overexpression or PDCD4 knockdown augmented MSC-mediated neuroprotective effects on acute glaucoma. These data highlight a previously unrecognized neuroprotective mechanism by which the miR-21/PDCD4 axis induces MSCs to secrete STC1 and other factors that exert neuroprotective effects. Therefore, modulating the miR-21/PDCD4 axis might be a promising strategy for clinical treatment of acute glaucoma and other neurological diseases. © The Author (2017). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, IBCB, SIBS, CAS. All rights reserved.

Filament-induced remote surface ablation for long range laser-induced breakdown spectroscopy operation

International Nuclear Information System (INIS)

Rohwetter, Ph.; Stelmaszczyk, K.; Woeste, L.; Ackermann, R.; Mejean, G.; Salmon, E.; Kasparian, J.; Yu, J.; Wolf, J.-P.

2005-01-01

We demonstrate laser induced ablation and plasma line emission from a metallic target at distances up to 180 m from the laser, using filaments (self-guided propagation structures ∼ 100 μm in diameter and ∼ 5 x 10 13 W/cm 2 in intensity) appearing as femtosecond and terawatt laser pulses propagating in air. The remarkable property of filaments to propagate over a long distance independently of the diffraction limit opens the frontier to long range operation of the laser-induced breakdown spectroscopy technique. We call this special configuration of remote laser-induced breakdown spectroscopy 'remote filament-induced breakdown spectroscopy'. Our results show main features of filament-induced ablation on the surface of a metallic sample and associated plasma emission. Our experimental data allow us to estimate requirements for the detection system needed for kilometer-range remote filament-induced breakdown spectroscopy experiment

Experience with the Ahmed Glaucoma Valve

African Journals Online (AJOL)

Design:Aprospective study of three glaucoma patients who had the Ahmed glaucoma valve implant at the. University of Benin ... Key words: glaucoma, glaucoma valve implant, ... introduced the micro-trephination with a diameter of. 0.6mm in ...

Neuroprotection in glaucoma

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Azadeh Doozandeh

2016-01-01

Full Text Available Glaucoma is a degenerative optic neuropathy characterized by retinal ganglion cell (RGC loss and visual field defects. It is known that in some glaucoma patients, death of RGCs continues despite intraocular pressure (IOP reduction. Neuroprotection in the field of glaucoma is defined as any treatment, independent of IOP reduction, which prevents RGC death. Glutamate antagonists, ginkgo biloba extract, neurotrophic factors, antioxidants, calcium channel blockers, brimonidine, glaucoma medications with blood regulatory effect and nitric oxide synthase inhibitors are among compounds with possible neuroprotective activity in preclinical studies. A few agents (such as brimonidine or memantine with neuroprotective effects in experimental studies have advanced to clinical trials; however the results of clinical trials for these agents have not been conclusive. Nevertheless, lack of compelling clinical evidence has not prevented the off-label use of some of these compounds in glaucoma practice. Stem cell transplantation has been reported to halt experimental neurodegenerative disease processes in the absence of cell replacement. It has been hypothesized that transplantation of some types of stem cells activates multiple neuroprotective pathways via secretion of various factors. The advantage of this approach is a prolonged and targeted effect. Important concerns in this field include the secretion of unwanted harmful mediators, graft survival issues and tumorigenesis. Neuroprotection in glaucoma, pharmacologically or by stem cell transplantation, is an interesting subject waiting for broad and multidisciplinary collaborative studies to better clarify its role in clinical practice.

Safety and efficacy of a low-cost glaucoma drainage device for refractory childhood glaucoma.

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Kaushik, Sushmita; Kataria, Pankaj; Raj, Srishti; Pandav, Surinder Singh; Ram, Jagat

2017-12-01

To evaluate the safety and efficacy of a low-cost glaucoma drainage device (GDD), Aurolab aqueous drainage implant (AADI), similar in design to the Baerveldt glaucoma implant (BGI), in refractory childhood glaucoma. This prospective interventional study was conducted in a tertiary care postgraduate teaching institute. Children aged glaucoma valve implant in children. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

[Uveitic Secondary Glaucoma].

Science.gov (United States)

Lommatzsch, Claudia; Heinz, Carsten

2018-05-01

An intraocular pressure increase with development of glaucomatous damage is a common complication of uveitis. The prevalence has a wide range depending on various factors such as the underlying uveitis type and the duration of the disease. Pathogenetically, a distinction must be made between a secondary angle closure component and the more frequently occurring open-angle glaucoma. In diagnostics, in addition to the clinical optic nerve head assessment, perimetry and tonometry, the use of imaging examination equipment, such as OCT and HRT, are recommended. In the context of uveitic glaucoma, it must be considered in the evaluation, because the glaucoma-typical changes are generally less pronounced or can be concealed by retinal swelling in comparison with other forms of glaucoma. Therapeutically, drug therapy in the form of eye drops continues to be a first-line recommendation, with the use of topical carbonic anhydrase inhibitors or beta-blockers primarily preferred, depending on the contraindications. An operative therapy follows after unsuccessful or inadequate conservative therapy: the adequate surgical technique depends on the respective finding and includes actually techniques such as filtering procedures and glaucoma drainage devices. Georg Thieme Verlag KG Stuttgart · New York.

The Advanced Glaucoma Intervention Study (AGIS): 11. Risk factors for failure of trabeculectomy and argon laser trabeculoplasty.

Science.gov (United States)

2002-10-01

To investigate the association of pre-intervention and post-intervention patient and eye characteristics with failure of argon laser trabeculoplasty (ALT) and trabeculectomy. Cohort study of participants in the Advanced Glaucoma Intervention Study. This multicenter study took place between 1988 and 2001. Between 1988 and 1992, 789 eyes of 591 patients aged 35 to 80 years with advanced glaucoma were randomized into one of two surgical treatment sequences: argon laser trabeculoplasty (ALT)-trabeculectomy-trabeculectomy or trabeculectomy-ALT-trabeculectomy. Upon study-defined failure (based on maximum medications, sustained intraocular pressure (IOP) elevation, visual field defect, and disk rim deterioration) of each intervention, patients were offered the subsequent intervention. Potential follow-up was 8 to 13 years. This report is based on data from 779 eyes that had at least 3 months of follow-up. The main outcome measures are failure of ALT and trabeculectomy, whether as first or second interventions. Effect size is measured by the hazard ratio (HR) and its corresponding 95% confidence interval (CI) obtained from Cox multiple regression analysis, where HR corresponds to the coefficient of change in risk associated with a unit increase in a factor. For binary factors, this corresponds to the change in risk in eyes with the factor relative to the risk in eyes without the factor. Pre-intervention factors associated with failure of ALT are younger age (HR = 0.98, CI = 0.96-0.99, P =.009) and higher IOP (1.11, 1.08-1.15, P <.001). Pre-intervention factors associated with failure of trabeculectomy are younger age (HR = 0.97, CI = 0.95-0.99, P =.005) and higher IOP (1.04, 1.01-1.06, P =.002), as well as diabetes (2.86, 1.88-4.36, P <.001) and any postoperative complication (1.99, 1.35-2.93, P <.001). Individual postoperative complications significantly associated with increased risk of failure of trabeculectomy are elevated IOP (3.4, 1.9-6.1, P <.001) and marked

Cambridge community Optometry Glaucoma Scheme.

Science.gov (United States)

Keenan, Jonathan; Shahid, Humma; Bourne, Rupert R; White, Andrew J; Martin, Keith R

2015-04-01

With a higher life expectancy, there is an increased demand for hospital glaucoma services in the United Kingdom. The Cambridge community Optometry Glaucoma Scheme (COGS) was initiated in 2010, where new referrals for suspected glaucoma are evaluated by community optometrists with a special interest in glaucoma, with virtual electronic review and validation by a consultant ophthalmologist with special interest in glaucoma. 1733 patients were evaluated by this scheme between 2010 and 2013. Clinical assessment is performed by the optometrist at a remote site. Goldmann applanation tonometry, pachymetry, monoscopic colour optic disc photographs and automated Humphrey visual field testing are performed. A clinical decision is made as to whether a patient has glaucoma or is a suspect, and referred on or discharged as a false positive referral. The clinical findings, optic disc photographs and visual field test results are transmitted electronically for virtual review by a consultant ophthalmologist. The number of false positive referrals from initial referral into the scheme. Of the patients, 46.6% were discharged at assessment and a further 5.7% were discharged following virtual review. Of the patients initially discharged, 2.8% were recalled following virtual review. Following assessment at the hospital, a further 10.5% were discharged after a single visit. The COGS community-based glaucoma screening programme is a safe and effective way of evaluating glaucoma referrals in the community and reducing false-positive referrals for glaucoma into the hospital system. © 2014 Royal Australian and New Zealand College of Ophthalmologists.

Surgical outcomes of the Ex-PRESS glaucoma filtration device in African American and white glaucoma patients

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Salim S

2012-06-01

Full Text Available Sarwat Salim, Haiming Du, Sumalee Boonyaleephan, Jim WanUniversity of Tennessee Health Science Center, Memphis, TN, USAPurpose: To compare the surgical outcomes of the Ex-PRESS glaucoma filtration device in African American and white glaucoma patients.Design: Retrospective comparative case series.Methods: This was a comparative case series of 36 eyes of 36 African Americans and 43 eyes of 43 whites that underwent placement of the Ex-PRESS glaucoma filtration device under a partial-thickness scleral flap for uncontrolled glaucoma. All eyes received intraoperative mitomycin C. The primary outcome measures were intraocular pressure (IOP, number of postoperative glaucoma medications, and surgical success. Surgical success was defined as IOP between 5 and 18 mm Hg, with or without glaucoma medications, without further glaucoma surgery, or loss of light perception vision. Results: Average follow-up was 31.9 ± 9.8 (range, 14.6–47 months for African Americans and 30.7 ± 8.6 (range, 14.3–47 months for whites. At 33 months, surgical success was 80.0% in the African American group and 83.3% in the white group (P = 1.00. Reasons for surgical failure included increased IOP (3 eyes, 3.8%, persistent hypotony with maculopathy (1 eye, 1.3%, and further surgery (4 eyes, 5.06%. Compared with preoperative values, the mean postoperative IOP and number of glaucoma medications were significantly reduced in both groups, and no statistical difference was observed between the two groups at 33 months. Postoperative complications were similar in the two groups.Conclusions: Similar surgical outcomes were observed in African American and white glaucoma patients after implantation of the Ex-PRESS glaucoma filtration device. This latest modification of glaucoma filtration surgery may be a better surgical option for African Americans given its potential advantages of no tissue removal, predictable outcomes related to consistent lumen size and controlled flow, fewer

[OCT and neovascular glaucoma].

Science.gov (United States)

Bellotti, A; Labbé, A; Fayol, N; El Mahtoufi, A; Baudouin, C

2007-06-01

Neovascular glaucoma is a chronic and sight-threatening disease. Four different grades have been described. Anterior chamber optical coherence tomography (OCT) is a new imaging technique allowing the visualization of the anterior segment. The purpose of our study was to describe the appearance of the different neovascular glaucoma grades with the OCT in order to refine the clinical analysis of this disease. Eleven patients (nine men and two women) with different grades of neovascular glaucoma were analyzed in this study. Neovascular glaucoma complicated central retinal vein occlusion in seven patients and diabetic retinopathy in four patients. All patients had bilateral biomicroscopical examination and OCT analysis. OCT images and clinical examination were then compared. No modifications could be observed using OCT in patients with grade 1 neovascular glaucoma. For grade 2, a slightly hyper-reflective linear iris secondary to neovascularization was observed. For grade 3, OCT images showed a thickened hyper-reflective iridocorneal angle with possible iridocorneal synechiae. For grade 4, the iridocorneal angle was closed and associated with iris contraction and uveae ectropion. OCT is a new promising technique for the precise analysis of different grades of neovascular glaucoma. It certainly helps in the management of such cases.

Targeting neuronal gap junctions in mouse retina offers neuroprotection in glaucoma

Science.gov (United States)

Kumar, Sandeep; Ramakrishnan, Hariharasubramanian; Roy, Kaushambi; Viswanathan, Suresh; Bloomfield, Stewart A.

2017-01-01

The progressive death of retinal ganglion cells and resulting visual deficits are hallmarks of glaucoma, but the underlying mechanisms remain unclear. In many neurodegenerative diseases, cell death induced by primary insult is followed by a wave of secondary loss. Gap junctions (GJs), intercellular channels composed of subunit connexins, can play a major role in secondary cell death by forming conduits through which toxic molecules from dying cells pass to and injure coupled neighbors. Here we have shown that pharmacological blockade of GJs or genetic ablation of connexin 36 (Cx36) subunits, which are highly expressed by retinal neurons, markedly reduced loss of neurons and optic nerve axons in a mouse model of glaucoma. Further, functional parameters that are negatively affected in glaucoma, including the electroretinogram, visual evoked potential, visual spatial acuity, and contrast sensitivity, were maintained at control levels when Cx36 was ablated. Neuronal GJs may thus represent potential therapeutic targets to prevent the progressive neurodegeneration and visual impairment associated with glaucoma. PMID:28604388

Comparison of efficacy of procedures in the treatment of acute angle-closure glaucoma

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Lian-Rong Su

2013-06-01

Full Text Available AIM: To observe the clinical effects of 3 different surgery treatments for acute angle-closure glaucoma. METHODS: Totally 60 cases of acute angle-closure glaucoma were randomly divided into 3 groups. Iris root excision or laser iridotomy was applied to group A, cataract phacoemulsification with artificial lens implantation and goniosynechialysis for group B, crabeculectomy for group C. The changes of vision, intraocular pressure, chamber angle, anterior chamber depth before and after operation were observed, while the postoperative complications and following operations were analyzed. The period of follow-up was one week, one month, three months and six months.RESULTS: No statistical significance was found for treatments of group A and C(P>0.05. For group C the treatment was statistically significant(PPPCONCLUSION: Cataract phacoemulsification with artificial lens implantation and goniosynechialysis is a safe and effective surgery for treatment of acute angle-closure glaucoma, which can effectively improve vision, decrease intraocular pressure, open anterior chamber angle.

The Difference in Translaminar Pressure Gradient and Neuroretinal Rim Area in Glaucoma and Healthy Subjects

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Lina Siaudvytyte

2014-01-01

Full Text Available Purpose. To assess differences in translaminar pressure gradient (TPG and neuroretinal rim area (NRA in patients with normal tension glaucoma (NTG, high tension glaucoma (HTG, and healthy controls. Methods. 27 patients with NTG, HTG, and healthy controls were included in the prospective pilot study (each group consisted of 9 patients. Intraocular pressure (IOP, intracranial pressure (ICP, and confocal laser scanning tomography were assessed. TPG was calculated as the difference of IOP minus ICP. ICP was measured using noninvasive two-depth transcranial Doppler device. The level of significance P 0.05. The difference between TPG for healthy (5.4(7.7 mmHg and glaucomatous eyes (NTG 6.3(3.1 mmHg, HTG 15.7(7.7 mmHg was statistically significant (P < 0.001. Higher TPG was correlated with decreased NRA (r = −0.83; P = 0.01 in the NTG group. Conclusion. Translaminar pressure gradient was higher in glaucoma patients. Reduction of NRA was related to higher TPG in NTG patients. Further prospective studies are warranted to investigate the involvement of TPG in glaucoma management.

[Role of laser peripheral iridotomy in pigmentary glaucoma and pigment dispersion syndrome: A review of the literature [French version

Science.gov (United States)

Buffault, J; Leray, B; Bouillot, A; Baudouin, C; Labbé, A

2017-12-01

Pigment dispersion syndrome (PSD) is characterized by a structural abnormality of the posterior surface of the iris causing contact with the zonular fibers. It can lead to an open-angle glaucoma secondary to pigment dispersion into the trabecular meshwork. Laser peripheral iridotomy (PI) has been proposed as a treatment for pigmentary glaucoma (PG) and pigment dispersion syndrome (PDS) by reducing the dispersion of pigment. The goal of this review was to assess the effects of PI for PSD and PG. We included six randomized controlled trials and two cohort studies (286 eyes of 218 participants). Four trials included participants with PG, and 4 trials enrolled participants with PSD with or without elevated intraocular pressure (IOP). Among patients with PG, at an average of 9 months of follow-up, the mean difference in IOP between groups was 2.69mmHg less in the PI group (95 % CI: -6.05 to 0.67; 14 eyes). In patients with PDS, the average IOP was statistically lower after PI as compared to baseline (Student test, t=11.49, P<0.01). With regard to visual field progression in participants with GP, after an average follow-up of 28 months, the risk of progression was not influenced by PI (RR 1.00 95 %: CI 0.16 to 6.25; 32 eyes). No trials that enrolled patients with PSD showed a diminution of the risk of glaucoma conversion at mid- and long-term. PI decreases the biomechanical factor causing contact between the iris and zonular fibers and may lower IOP over the long-term. Nevertheless, the effects of PI on visual field changes or progression have not been established in PG and PDS. There is no scientific evidence as of yet to advocate PI as a treatment for PDS or PG. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Study of surgical treatment on neovascular glaucoma

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Xiao-Nü Liu

2014-05-01

Full Text Available AIM: To compare the effect of two surgical methods on neovascular glaucoma(NVG. METHODS: The clinical date of 46 cases(57 eyeswith NVG underwent surgical treatment were retrospectively analyzed and followed-up. Patients were divided into Ahmed glaucoma valve(AGVimplantation group(group A, 24 cases, 31 eyesand semiconductor diode laser transscleral ciliary body photocoagulation(TSCPCgroup(group B, 22cases, 26 eyesaccording to the surgical approach. The intraocular pressure, visual acuity and postoperative complications were compared before and after operation. RESULTS: The intraocular pressure postoperative in two groups were significantly lower than those preoperative(P P>0.05. The changes of visual acuity postoperative showed no statistical difference between the two groups(P>0.05. The postoperative complications of group A was significantly lower than that in group B, in which the incidence of eye pain, anterior chamber bleeding were significant differences between two groups(P CONCLUSION: AGV implantation treatment and TSCPC for NVG are both valid, but AGV implantation is filtration surgery, and TSCPC isciliary body destructive surgery, and the latter has higher rate of postoperative complications.

Glaucoma: a brief update for 2017

African Journals Online (AJOL)

glaucoma. Predictions are that glaucoma will affect almost ... Abstract. Glaucoma is a complex condition of the eye and the second leading cause of blindness around the globe. ..... a stinging sensation upon instilling the drops into the eyes, as well as dry eyes .... Dimitriou C, Broadway D. Pathophysiology of glaucoma.

Risks induced by laser radiation; Risques induits par le rayonnement laser

Energy Technology Data Exchange (ETDEWEB)

Courant, D [CEA Fontenay-aux-Roses, 92 (France). Dept. de Radiobiologie et de Radiopathologie

2001-07-01

The use of lasers is often dangerous because of the emitted power, the wave length, the conduction system(optical fiber, wave guide, mirrors) and the use conditions. The safety notion involves the precise knowledge of materials, the biological effects in function of laser emission parameters, the knowledge of protection standards, the observance of use rules and the personnel training. This chapter treats the risks induced by the beam. It gives the different biological effects induced by the laser beam, at the eye and skin levels that are at the origin of exposure limits and the lasers classification recommended by the protection standards. (N.C.)

Short term outcome of Ahmed glaucoma valve implantation in management of refractory glaucoma in a tertiary hospital in Oman

Science.gov (United States)

Shah, Manali R.; Khandekar, Rajiv B.; Zutshi, Rajiv; Mahrooqi, Rahima

2013-01-01

Background: We present outcomes of Ahmed Glaucoma Valve (AGV) implantation in treating refractory glaucoma in a tertiary hospital in Oman. Refractory glaucoma was defined as previously failed conventional glaucoma surgery and an uncontrolled intraocular pressure (IOP) of more than 21 mm Hg despite treatment with three topical and/or oral therapy. Materials and Methods: This historical cohort study was conducted in 2010. Details of medical and surgical treatment were recorded. Ophthalmologists examined eyes and performed glaucoma surgeries using AGV. The best corrected distant vision, IOP, and glaucoma medications were prospectively reviewed on 1st day, 1st, 6th, 12th week postoperatively, and at the last follow up. Result: Glaucoma specialists examined and treated 40 eyes with refractory glaucoma of 39 patients (20 males + 19 females). Neo-vascular glaucoma was present in 23 eyes. Vision before surgery was glaucoma medications (2.38; SD 1.1) was reduced compared to the mean number of postoperative medications (1.92; SD 0.9) at 12 weeks. Conclusion: We succeeded in reducing visual disabilities and the number of anti-glaucoma medications used to treat refractory glaucoma by AGV surgery. PMID:23772122

Interocular asymmetry of the visual field defects in newly diagnosed normal-tension glaucoma, primary open-angle glaucoma, and chronic angle-closure glaucoma.

Science.gov (United States)

Huang, Ping; Shi, Yan; Wang, Xin; Liu, Mugen; Zhang, Chun

2014-09-01

To compare the interocular asymmetry of visual field loss in newly diagnosed normal-tension glaucoma (NTG), primary open-angle glaucoma (POAG), and chronic angle-closure glaucoma (CACG) patients. Visual field results of 117 newly diagnosed, treatment-naive glaucoma patients (42 NTG, 38 POAG, and 37 CACG) were studied retrospectively. The following 3 visual field defect parameters were used to evaluate the interocular asymmetry: (1) global indices; (2) local mean deviations (MDs) of 6 predefined visual field areas; and (3) stage designated by glaucoma staging system 2. The differences of the above parameters between the trial eye (the eye with greater MDs) and the fellow eye in each subject were defined as interocular asymmetry scores. Interocular asymmetry of visual field loss was presented in all the 3 groups (all P0.05). Interocular asymmetry scores of glaucoma staging system 2 had no significant difference among the 3 groups (P=0.068). All CACG, POAG, and NTG groups presented with interocular asymmetric visual field loss at the time of diagnosis. CACG had greater interocular asymmetry compared with NTG and POAG. No significant interocular asymmetry difference was observed between NTG and POAG.

The future of glaucoma surgery

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Arsham Sheybani

2015-01-01

Full Text Available Glaucoma surgery is ripe for innovation. In the last few years, there has been a substantial increase in the number of devices approaching commercialization. While not all that is new is necessarily good, the role of these devices in changing glaucoma surgery is equally important in terms of both success and failure. Trabeculectomy, the most commonly performed incisional filtration surgery for glaucoma, is subjective by nature and certainly has risks. As devices aim to standardize glaucoma surgery, specifically subconjunctival filtration surgery, predictability and in turn safety should theoretically improve. This may allow the glaucoma surgeon to intervene earlier in the disease process, prevent more advanced vision loss and potentially decrease the burden of medications.

Angle closure glaucoma in congenital ectropion uvea

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Grace M. Wang

2018-06-01

Full Text Available Purpose: Congenital ectropion uvea is a rare anomaly, which is associated with open, but dysplastic iridocorneal angles that cause childhood glaucoma. Herein, we present 3 cases of angle-closure glaucoma in children with congenital ectropion uvea. Observations: Three children were initially diagnosed with unilateral glaucoma secondary to congenital ectropion uvea at 7, 8 and 13 years of age. The three cases showed 360° of ectropion uvea and iris stromal atrophy in the affected eye. In one case, we have photographic documentation of progression to complete angle closure, which necessitated placement of a glaucoma drainage device 3 years after combined trabeculotomy and trabeculectomy. The 2 other cases, which presented as complete angle closure, also underwent glaucoma drainage device implantation. All three cases had early glaucoma drainage device encapsulation (within 4 months and required additional surgery (cycloablation or trabeculectomy. Conclusions and importance: Congenital ectropion uvea can be associated with angle-closure glaucoma, and placement of glaucoma drainage devices in all 3 of our cases showed early failure due to plate encapsulation. Glaucoma in congenital ectropion uvea requires attention to angle configuration and often requires multiple surgeries to obtain intraocular pressure control. Keywords: Congenital ectropion uvea, Juvenile glaucoma, Angle-closure glaucoma, Glaucoma drainage device

Glaucoma in developing countries

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Ravi Thomas

2012-01-01

Full Text Available Objective: To describe the background and strategy required for the prevention of blindness from glaucoma in developing countries. Materials and Methods: Extrapolation of existing data and experience in eye care delivery and teaching models in an unequally developed country (India are used to make recommendations. Results: Parameters like population attributable risk percentage indicate that glaucoma is a public health problem but lack of simple diagnostic techniques and therapeutic interventions are barriers to any effective plan. Case detection rather than population-based screening is the recommended strategy for detection. Population awareness of the disease is low and most patients attending eye clinics do not receive a routine comprehensive eye examination that is required to detect glaucoma (and other potentially blinding eye diseases. Such a routine is not taught or practiced by the majority of training institutions either. Angle closure can be detected clinically and relatively simple interventions (including well performed cataract surgery can prevent blindness from this condition. The strategy for open angle glaucoma should focus on those with established functional loss. Outcomes of this proposed strategy are not yet available. Conclusions: Glaucoma cannot be managed in isolation. The objective should be to detect and manage all potential causes of blindness and prevention of blindness from glaucoma should be integrated into existing programs. The original pyramidal model of eye care delivery incorporates this principle and provides an initial starting point. The routine of comprehensive eye examination in every clinic and its teaching (and use in residency programs is mandatory for the detection and management of potentially preventable blinding pathology from any cause, including glaucoma. Programs for detection of glaucoma should not be initiated unless adequate facilities for diagnosis and surgical intervention are in place and

Effect of laser spot size on energy balance in laser induced plasmas

International Nuclear Information System (INIS)

Pant, H.C.; Sharma, S.; Bhawalkar, D.D.

1980-01-01

The effect of the laser spot size on laser light absorption in laser induced plasmas from solid targets was studied. It was found that at a constant laser intensity on the target, reduction in the laser spot size enhances the net laser energy absorption. It was also observed that the laser light reflection from the target becomes more diffused when the focal spot size is reduced

Progress of inflammatory cytokines in glaucoma

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Ping Hu

2015-12-01

Full Text Available Glaucomais a group of diseases characterized by optic nerve damage and visual field defect, and pathological high intraocular pressure is a risk factor for glaucoma. Glaucoma is affected by the interaction of multiple genes and environmental factors, and inflammation may be involved in the pathogenesis of glaucoma. A great deal of studies have confirmed that high expression of connective tissue growth factor(CTGF, tumor necrosis factor-α(TNF-α, interleukins(ILs, nuclear factor-kappa B(NF-κBand various cytokines in the aqueous humor of patients with glaucoma, which have a close correlation with pathogenesis of glaucoma.This article reviews the progress of inflammatory cytokines and their relationship with glaucoma.

Clinical Metabolomics and Glaucoma.

Science.gov (United States)

Barbosa-Breda, João; Himmelreich, Uwe; Ghesquière, Bart; Rocha-Sousa, Amândio; Stalmans, Ingeborg

2018-01-01

Glaucoma is one of the leading causes of irreversible blindness worldwide. However, there are no biomarkers that accurately help clinicians perform an early diagnosis or detect patients with a high risk of progression. Metabolomics is the study of all metabolites in an organism, and it has the potential to provide a biomarker. This review summarizes the findings of metabolomics in glaucoma patients and explains why this field is promising for new research. We identified published studies that focused on metabolomics and ophthalmology. After providing an overview of metabolomics in ophthalmology, we focused on human glaucoma studies. Five studies have been conducted in glaucoma patients and all compared patients to healthy controls. Using mass spectrometry, significant differences were found in blood plasma in the metabolic pathways that involve palmitoylcarnitine, sphingolipids, vitamin D-related compounds, and steroid precursors. For nuclear magnetic resonance spectroscopy, a high glutamine-glutamate/creatine ratio was found in the vitreous and lateral geniculate body; no differences were detected in the optic radiations, and a lower N-acetylaspartate/choline ratio was observed in the geniculocalcarine and striate areas. Metabolomics can move glaucoma care towards a personalized approach and provide new knowledge concerning the pathophysiology of glaucoma, which can lead to new therapeutic options. © 2017 S. Karger AG, Basel.

Ahmed Glaucoma Valve Implantation for Uveitic Glaucoma Secondary to Behçet Disease.

Science.gov (United States)

Satana, Banu; Yalvac, Ilgaz S; Sungur, Gulten; Eksioglu, Umit; Basarir, Berna; Altan, Cigdem; Duman, Sunay

2015-01-01

To evaluate outcomes of patients with uveitic glaucoma secondary to Behçet disease (BD) who underwent Ahmed glaucoma valve (AGV) implantation. A retrospective chart review of 14 eyes of 10 patients with uveitic glaucoma associated with BD who underwent AGV implantation at a tertiary referral center. Treatment success was defined as intraocular pressure (IOP) between 6 and 21 mm Hg with or without antiglaucoma medication, without further additional glaucoma surgery or loss of light perception. The main outcome measures were IOP, best-corrected visual acuity measured with Snellen charts, and number of glaucoma medications. Mean duration of postoperative follow-up was 18.2±6.6 months (range, 6 to 31 mo). Of the 14 eyes, 10 (71.4%) were pseudophakic and 5 (35.7%) had primary AGV implantation without a history of previous glaucoma surgery. At the most recent follow-up visit, 13 of the 14 eyes had an IOP between 6 and 21 mm Hg. Mean IOP was significantly reduced during follow-up, as compared with preoperative values (P≤0.005). The cumulative probability of surgical success rate was 90.9% at 18 months based on Kaplan-Meier survival analysis. The mean number of antiglaucoma medications required to achieve the desired IOP decreased from 3.4±0.5 preoperatively to 1.0±1.1 postoperatively (P≤0.05). Visual acuity loss of >2 lines occurred in 4 eyes (28.5%) due to optic atrophy associated with retinal vasculitis. Temporary hypotony developed during follow-up in 4 eyes (28.5%) at first postoperative week. For the management of uveitic glaucoma associated with BD, AGV implantation is a successful method for glaucoma control but requires additional surgical interventions for high early hypotony rates.

Clinical observation on Ahmed glaucoma valve implantation for teenagers with refractory glaucoma

Directory of Open Access Journals (Sweden)

Dong-Dao Song

2016-06-01

Full Text Available AIM:To observe the clinical effect of Ahmed glaucoma valve(AGVimplantation for teenagers with refractory glaucoma. METHODS: Twenty-seven patients(27 eyeswith refractory glaucoma were treated with AGV implantation in our hospital from October 2012 to October 2014. The patients were followed up for 12mo. The success rate of the operation, postoperative intraocular pressure, the best corrected visual acuity, as well as complications were recorded. RESULTS: The success rate of the operation was 85%. The intraocular pressure of the 27 patients decreased from 48.3±8.3mmHg before operations to 21.4±8.1mmHg(PPCONCLUSION: AGV implantation is characterized by a high success rate, simple operation, less complications and is an effective treatment for refractory glaucoma in adolescents.

Adherence to Follow-up Recommendations Among Individuals in the Philadelphia Glaucoma Detection and Treatment Project.

Science.gov (United States)

Hark, Lisa A; Leiby, Benjamin E; Waisbourd, Michael; Myers, Jonathan S; Fudemberg, Scott J; Mantravadi, Anand V; Dai, Yang; Gilligan, John P; Resende, Arthur F; Katz, L Jay

2017-08-01

To evaluate rates of adherence to free follow-up eye exam appointments among participants in the Philadelphia Glaucoma Detection and Treatment Project. Ophthalmologists and testing equipment were brought directly to participants at risk for glaucoma at 43 community sites in Philadelphia. Those diagnosed with glaucoma-related pathology were recommended to return for follow-up to be reexamined on site. Rates of adherence and clinical and demographic risk factors for adherence were evaluated. Five hundred thirty-one participants were diagnosed with glaucoma-related conditions and recommended to attend community-based follow-up exams. Follow-up adherence rate was 61.2% (n=325/531). Significant factors associated with greater eye exam appointment adherence, based on our univariable analysis, included final diagnosis of glaucoma (risk ratio [RR]=1.33; 95% confidence interval [CI], 1.13-1.57), male sex (RR=1.19; 95% CI, 1.04-1.36), white race (RR=1.26; 95% CI, 1.08-1.48), age (RR=1.17; 95% CI, 1.00-1.37) recommendation for glaucoma medication (RR=1.52; 95% CI, 1.35-1.71), recommendation for laser peripheral iridotomy (RR=1.18; 95% CI, 1.02-1.35), diagnosis of age-related macular degeneration (RR=1.42; 95% CI, 1.13-1.77) and an increased intraocular pressure (>22 mm Hg in the worse eye) (RR=1.23; 95% CI, 1.06-1.42). On the basis of our multivariable model, diagnosis, sex, and recommended glaucoma medications were significantly associated with follow-up adherence. This study demonstrates that individuals living in underserved urban communities would take advantage of free eye exams in community sites and return for follow-up eye exams in these same settings. Future studies could investigate interventions to improve eye exam appointment adherence in community-based settings to detect glaucoma-eye conditions.

Altered aquaporin expression in glaucoma eyes

DEFF Research Database (Denmark)

Tran, Thuy Linh; Bek, Toke; Cour, Morten la

2014-01-01

Aquaporins (AQP) are channels in the cell membrane that mainly facilitate a passive transport of water. In the eye, AQPs are expressed in the ciliary body and retina and may contribute to the pathogenesis of glaucoma and optic neuropathy. We investigated the expression of AQP1, AQP3, AQP4, AQP5......, AQP7 and AQP9 in human glaucoma eyes compared with normal eyes. Nine glaucoma eyes were examined. Of these, three eyes were diagnosed with primary open angle glaucoma; three eyes had neovascular glaucoma; and three eyes had chronic angle-closure glaucoma. Six eyes with normal intraocular pressure...... and without glaucoma were used as control. Immunohistochemistry was performed using antibodies against AQP1, AQP3, AQP4, AQP5, AQP7 and AQP9. For each specimen, optical densities of immunoprecipitates were measured using Photoshop and the staining intensities were calculated. Immunostaining showed labelling...

Laser-induced breakdown spectroscopy analysis of asbestos

International Nuclear Information System (INIS)

Caneve, L.; Colao, F.; Fabbri, F.; Fantoni, R.; Spizzichino, V.; Striber, J.

2005-01-01

Laser-induced breakdown spectroscopy was applied to test the possibility of detecting and identifying asbestos in different samples in view of the perspective at field operation without sample preparation which is peculiar to this technique. Several like-resin materials were first investigated by laser-induced breakdown spectroscopy, in order to find an asbestos container assuring safe laboratory operation during the material characterization aimed to identify indicators suitable for a quick identification on field. Successively, spectra of asbestos samples of both in serpentine and amphibole forms were measured and the variability in elemental composition was calculated from the emission spectra. Ratios of intensities of characteristic elements were tested as indicators for asbestos recognition. Laser-induced breakdown spectroscopy results were compared with those obtained by analyzing the same asbestos samples with a scanning electron microscopy equipped with an energy dispersive X-ray spectroscopy, a good correlation was found for Mg/Si and Fe/Si, thus showing the capability of laser-induced breakdown spectroscopy as a diagnostic tool for this category of materials. In particular, it was demonstrated that the method based on two indicators derived from laser-induced breakdown spectroscopy intensity ratios allows to discriminate between asbestos and cements in single shot measurements suitable to field operation

Late-Onset Endophthalmitis Secondary to Exposed Glaucoma Tube Implant in a Rare Case of Paediatric Glaucoma

OpenAIRE

Ranganath, Akshatha; Hashim, Adnan

2011-01-01

Glaucoma drainage implants (GDIs) are used to treat paediatric glaucoma resistant to conventional medical and surgical treatment, achieving good intraocular pressure (IOP) control and long-term success. Late endophthalmitis is a rare complication that may develop following GDI surgery. A 17-year-old male presented with acute endophthalmitis 2 years after Ahmed glaucoma valve implantation with pericardial patch graft for management of refractory glaucoma secondary to congenital ectropion uveae...

Laser-induced stresses versus mechanical stress power measurements during laser ablation of solids

International Nuclear Information System (INIS)

Shannon, M.A.; Russo, R.E.

1995-01-01

Laser-induced stresses resulting from high-power laser-material interactions have been studied extensively. However, the rate of change in mechanical energy, or stress power, due to laser-induced stresses has only recently been investigated. An unanswered question for monitoring laser-material interactions in the far-field is whether stress power differs from stresses measured, particularly with respect to laser-energy coupling to a solid target. This letter shows experimental acoustic data which demonstrate that stress power measured in the far field of the target shows changes in laser-energy coupling, whereas the stresses measured do not. For the ambient medium above the target, stress power and stress together reflect changes in laser-energy coupling. copyright 1995 American Institute of Physics

Advanced Morphological and Functional Magnetic Resonance Techniques in Glaucoma

Directory of Open Access Journals (Sweden)

Rodolfo Mastropasqua

2015-01-01

Full Text Available Glaucoma is a multifactorial disease that is the leading cause of irreversible blindness. Recent data documented that glaucoma is not limited to the retinal ganglion cells but that it also extends to the posterior visual pathway. The diagnosis is based on the presence of signs of glaucomatous optic neuropathy and consistent functional visual field alterations. Unfortunately these functional alterations often become evident when a significant amount of the nerve fibers that compose the optic nerve has been irreversibly lost. Advanced morphological and functional magnetic resonance (MR techniques (morphometry, diffusion tensor imaging, arterial spin labeling, and functional connectivity may provide a means for observing modifications induced by this fiber loss, within the optic nerve and the visual cortex, in an earlier stage. The aim of this systematic review was to determine if the use of these advanced MR techniques could offer the possibility of diagnosing glaucoma at an earlier stage than that currently possible.

[Postoperative unilateral acute glaucoma after abdominal surgery].

Science.gov (United States)

Hidalgo Grau, L A; Opisso Juliá, L L; Roqué Meseguer, A; Yuste Graupera, M; Suñol Sala, X

2012-11-01

An early and correct diagnosis substantially improves the post-operative prognosis of acute angle closure glaucoma (AACG). A 90 year-old woman was operated on for a right colon tumour by laparotomy, under combined anaesthesia without any adverse events. Twelve hours after the operation, the patient described recurrent periorbital pain in her right eye, with ocular hyperaemia, blurred vision, and unresponsive mydriasis. A diagnosis of AACG was made, but although conservative treatment was started YAG laser iridotomies were required to reduce the intraocular pressure. In the AACG postoperative period, as well as with an eye with several predisposed local factors including genetic predisposition, female gender, hypermetropia, increased lens thickness and small corneal diameter, can be added a pupillary block induced by adrenergic and anticholinergic drugs used in anaesthetic procedures. An acute and intensive periorbital or ocular pain, with or without visual disturbance, must aware the doctor. A differential diagnosis with other postoperative ocular diseases and cranial pain causes must be done. Copyright © 2011 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

The effect of an Ahmed glaucoma valve implant on corneal endothelial cell density in children with glaucoma secondary to uveitis.

Science.gov (United States)

Kalinina Ayuso, Viera; Scheerlinck, Laura M; de Boer, Joke H

2013-03-01

To assess the effect of Ahmed glaucoma valve implants on corneal endothelial cell density (ECD) in children with uveitic glaucoma. Cross-sectional study. setting: Institutional. patientpopulation: Eighty eyes from 42 patients diagnosed with uveitis before the age of 16. Twenty-eight eyes had an Ahmed glaucoma valve implant because of secondary glaucoma. Fifty-two eyes without an implant served as controls. intervention orobservationprocedure(s): Corneal ECD was examined cross-sectionally using a noncontact specular microscope. Univariate and multivariate generalized estimating equations analyses with correction for paired eyes were performed. mainoutcomemeasure(s): Correlation of ECD with the presence of an Ahmed glaucoma valve implant and with the time following implantation. ECD was significantly lower in the Ahmed glaucoma valve group than in controls (2359 and 3088 cells/mm(2), respectively; P Ahmed glaucoma valve implantation. Presence of an Ahmed glaucoma valve implant, previous intraocular surgery, age, duration of uveitis, and history of corneal touch by the implant tube were all significantly associated with decreased ECD. Following a multivariate analysis, presence of an Ahmed glaucoma valve implant (B = -340; adjusted P Ahmed glaucoma valve implantation was highly correlated with decreased ECD (B = -558, P Ahmed glaucoma valve implants in children with uveitic glaucoma are independently associated with decreased ECD, and this effect is associated with the time interval following Ahmed glaucoma valve implantation. Copyright © 2013 Elsevier Inc. All rights reserved.

Diode laser cyclophotocoagulation in Indian eyes: efficacy and safety.

Science.gov (United States)

Singh, Kirti; Jain, Divya; Veerwal, Vikas

2017-02-01

Diode laser cyclophotocoagulation (DLCP) has emerged as a time-tested procedure for end-stage glaucoma with fewer complications. By means of this study, we have evaluated its wide indications, its efficacy, and safety in darkly pigmented Asian Indian eyes. Ninety-one eyes with uncontrolled glaucoma presenting to glaucoma clinic of a tertiary care center over a period of 6 years were scheduled for DLCP. The semiconductor diode laser with a G probe was used with laser energy delivered about 1.5 mm behind the surgical limbus. The extent of clock hours of laser application was determined by pretreatment intraocular pressure (IOP) and superior area was spared in cases where future filtration surgery was contemplated. The DLCP was repeated earliest at 1 month in case of non-response and a maximum of three laser procedures were performed for any patient. Ninety-one eyes of 89 patients (40 males, 49 females) were included. Common indications included secondary glaucoma (37.3 %), failed trabeculectomies (27.4 %), angle closure glaucoma (17.5 %), etc. Laser power delivered ranged from 990 to 1800 mW, (mean 1396 + 182.14 mW) with an average of 17 spots. Patients improved from pretreatment IOP of 38.18 + 8.96 mmHg (range 20.6-64) to post treatment IOP of 17.86 + 7.75 mmHg (range 10-42). Qualified success was defined as final IOP of 20 mm Hg or less on topical medications that could be achieved in 70 % eyes with one or repeat treatment. Pre op visual acuity ranged from PL+ to 6/18 showing a slight improvement to PL+ to 6/12 post op. A 58.5 % reduction of IOP was noted. No incidence of serious complications was noted during follow-up ranging from 9 months to 3 years. DLCP is an effective and safe tool to be used in Indian population for control of IOP. It can be safely used as a primary modality to bring IOP to permissible levels before trabeculectomy.

Genetics Home Reference: early-onset glaucoma

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... called a syndrome. If glaucoma appears before the age of 5 without other associated abnormalities, it is called primary congenital glaucoma. Other individuals experience early onset of primary open-angle glaucoma, the most ...

Developmental approach towards high resolution optical coherence tomography for glaucoma diagnostics

Science.gov (United States)

Kemper, Björn; Ketelhut, Steffi; Heiduschka, Peter; Thorn, Marie; Larsen, Michael; Schnekenburger, Jürgen

2018-02-01

Glaucoma is caused by a pathological rise in the intraocular pressure, which results in a progressive loss of vision by a damage to retinal cells and the optical nerve head. Early detection of pressure-induced damage is thus essential for the reduction of eye pressure and to prevent severe incapacity or blindness. Within the new European Project GALAHAD (Glaucoma Advanced, Label free High Resolution Automated OCT Diagnostics), we will develop a new low-cost and high-resolution OCT system for the early detection of glaucoma. The device is designed to improve diagnosis based on a new system of optical coherence tomography. Although OCT systems are at present available in ophthalmology centres, high-resolution devices are extremely expensive. The novelty of the new Galahad system is its super wideband light source to achieve high image resolution at a reasonable cost. Proof of concept experiments with cell and tissue Glaucoma test standards and animal models are planned for the test of the new optical components and new algorithms performance for the identification of Glaucoma associated cell and tissue structures. The intense training of the software systems with various samples should result in a increased sensitivity and specificity of the OCT software system.

Arguments Against Funding Glaucoma Treatment and Rebuttal

African Journals Online (AJOL)

2018-03-01

Mar 1, 2018 ... for the treatment of glaucoma at no cost to IWG at the point of delivery toward reducing glaucoma,s harmful impact on the .... and logistic reasons. Nigeria doesn .... cataract unlike from glaucoma can be reversed. This does not.

[Basic and clinical studies of pressure-independent damaging factors of open angle glaucoma].

Science.gov (United States)

Araie, Makoto

2011-03-01

Pathogenesis of open-angle glaucoma involves both pressure-dependent damaging factors and pressure-independent damaging factors. The high prevalence of open-angle glaucoma with normal pressure (normal-tension glaucoma) in Japan implies that treatment of pressure-independent damaging factors in Japanese open-angle glaucoma patients is of importance. In an attempt to investigate the roles of pressure-independent damaging factors in open-angle glaucoma, we carried out basic and clinical studies and obtained the following results. 1. The rate of deterioration of visual field after trabeculectomy in normal tension glaucoma patients with post-operative intraocular pressure (IOP) of 10 mmHg was found to be -0.25 dB/year of mean deviation (MD), suggesting that contribution of pressure-independent damaging factors to the deterioration of MD in open-angle glaucoma is around -0.25 dB/year of mean deviation (MD). 2. Experiments using isolated purified cultured retinal ganglion cells (RGCs) indicated that calcium-channel blockers and some of antiglaucoma drugs showed neuroprotective effects on RGCs at concentrations of 0.01 microM or higher. 3. In mice, damage to RGCs resulted in secondary degeneration of neurons and activation of glial cells in the lateral geniculate nucleous (LGN) and superior colliculus, and these secondary changes in the central nervous system (CNS) due to RGC damage was partly ameliorated by systemic administration of memantine. 4. Mice experimental high IOP glaucoma models could be established using laser irradiation of the limbal area, and the usefulness of Tonolab in IOP measurements of mice eye was confirmed. 5. Monkey experimental high IOP glaucoma models revealed that in the glaucomatous optic nerve head vaso-constrictive reactions to an alpha-1 agonist was abolished, while vasodilative reaction to a prostaglandin FP receptor agonist was retained. 6. In monkeys with experimental high IOP glaucoma, secondary damage to neurons in the LGN and the glial

Management of sulcus-fixated single-piece intraocular lens-induced pigmentary glaucoma with 3-piece IOL exchange.

Science.gov (United States)

Rabie, Hossein Mohammad; Esfandiari, Hamed; Rikhtegar, Mohammad Hassan; Hekmat, Vahid

2018-02-01

To describe our experience with exchanging sulcus-fixated single-piece intraocular lens (IOL) with 3-piece IOLs for management of pigmentary glaucoma. In this retrospective study, records of patients who underwent sulcus-fixated single-piece IOL exchanged with 3-piece IOLs were retrieved, and demographic and baseline data of patients, type of IOL, pre- and post-IOL exchange BCVA, IOP, number of anti-glaucoma medications, and optic nerve head examination were documented. Baseline and final examinations were analyzed and compared. Mean age of the patients was 59 ± 10 years, and 5 (41.6%) were female. Mean interval between primary cataract extraction operation and IOL exchange was 17 ± 5 months. Nine patients received in sulcus implantation of Alcon SA60AT, and three patients had SN60WF model at the end of primary surgery. BCVA changed insignificantly from 0.06 ± 0.06 logMAR to 0.06 ± 0.06 after IOL exchange. (P = 0.22) IOP was controlled in 8 cases (66.6%), but four cases (33.3%) needed glaucoma surgery to further control glaucoma condition. IOP decreased significantly from preoperative 17 ± 3 to 14 ± 1 mmHg postoperatively. Patients with advanced age and higher baseline IOP were more likely to undergo glaucoma surgery after IOL exchange. (P = 0.07 and 0.00, respectively). single-piece IOL exchange with 3-piece IOL dramatically decreases pigment release and reduces IOP. Those with advanced age and higher IOP are less likely to respond to IOL exchange and may need glaucoma surgery to control high intraocular pressure.

Glaucoma in Asian Populations

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... Involved News About Us Donate In This Section Glaucoma In Asian Populations email Send this article to ... lower than in their Asian counterparts. Normal Tension Glaucoma affects Japanese Japanese populations, however, have a substantially ...

African Americans and Glaucoma

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... Us Donate In This Section African Americans and Glaucoma email Send this article to a friend by ... and eventually, in developing more effective treatments. Does glaucoma treatment differ? Although treatment varies for all individuals, ...

Costs of a community-based glaucoma detection programme: analysis of the Philadelphia Glaucoma Detection and Treatment Project.

Science.gov (United States)

Pizzi, Laura T; Waisbourd, Michael; Hark, Lisa; Sembhi, Harjeet; Lee, Paul; Crews, John E; Saaddine, Jinan B; Steele, Deon; Katz, L Jay

2018-02-01

Glaucoma is the foremost cause of irreversible blindness, and more than 50% of cases remain undiagnosed. Our objective was to report the costs of a glaucoma detection programme operationalised through Philadelphia community centres. The analysis was performed using a healthcare system perspective in 2013 US dollars. Costs of examination and educational workshops were captured. Measures were total programme costs, cost/case of glaucoma detected and cost/case of any ocular disease detected (including glaucoma). Diagnoses are reported at the individual level (therefore representing a diagnosis made in one or both eyes). Staff time was captured during site visits to 15 of 43 sites and included time to deliver examinations and workshops, supervision, training and travel. Staff time was converted to costs by applying wage and fringe benefit costs from the US Bureau of Labor Statistics. Non-staff costs (equipment and mileage) were collected using study logs. Participants with previously diagnosed glaucoma were excluded. 1649 participants were examined. Mean total per-participant examination time was 56 min (SD 4). Mean total examination cost/participant was $139. The cost/case of glaucoma newly identified (open-angle glaucoma, angle-closure glaucoma, glaucoma suspect, or primary angle closure) was $420 and cost/case for any ocular disease identified was $273. Glaucoma examinations delivered through this programme provided significant health benefit to hard-to-reach communities. On a per-person basis, examinations were fairly low cost, though opportunities exist to improve efficiency. Findings serve as an important benchmark for planning future community-based glaucoma examination programmes. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Evaluation of ExPress glaucoma filtration device in Indian patients with advanced glaucoma.

Science.gov (United States)

Angmo, Dewang; Sharma, Reetika; Temkar, Shreyas; Dada, Tanuj

2015-05-01

ExPress glaucoma filtration device (GFD) has recently become available in India as a surgical option for glaucoma patients. We retrospectively evaluated the outcome of ExPress GFD in 12 eyes with advanced glaucoma with intraocular pressures (IOPs) not controlled on maximal tolerable medical therapy. The mean preoperative IOP of 29.58 ± 7.13 mmHg decreased to 17.0 ± 2.67 and 17.40 ± 0.89 mmHg at 6 and 12 months after surgery. Absolute success (IOP ≤ 18 mmHg, with no additional glaucoma medications) was achieved in eight cases (66.7%) and qualified success (IOP ≤ 18 mmHg, with additional glaucoma medications) in two cases (16.7%) at 1-year after surgery. Early intervention was needed in 4 patients; two underwent anterior chamber reformation while the other two required needling. Two patients required resurgery. There was no significant change in the best corrected visual acuity postoperatively (P = 0.37). ExPress GFD does not seem to offer a benefit over standard trabeculectomy in patients with advanced glaucomatous disease in terms of IOP control or complication rate. However, due to the small sample size with a heterogeneous mixture of primary and secondary glaucoma's, we await further studies with a larger sample size and long-term follow-up, to see how the device performs.

Faraday cup measurements of a laser-induced plasma for a laser-proton acceleration

International Nuclear Information System (INIS)

Park, Seong Hee; Jeong, Young Uk; Lee, Ki Tae

2006-01-01

Experiments for the generation of laser-induced protons were performed in collaboration with Advanced Photonics Research Institute (APRI). An intensity of 3 X 10 18 W/cm 2 was delivered to a 17-μm Al target, and the Faraday Cup signals of the charged particles generated by the laser-plasma interaction were measured. In this paper, we discuss the first experimental results of laser-induced proton generation using the APRI laser and report on the feasibility of current measurement for charged-particles when using a Faraday cup.

A Quantitative Analysis of the Relationship between Medicare Payment and Service Volume for Glaucoma Procedures from 2005 through 2009.

Science.gov (United States)

Gong, Dan; Jun, Lin; Tsai, James C

2015-05-01

To calculate the association between Medicare payment and service volume for 6 commonly performed glaucoma procedures. Retrospective, longitudinal database study. A 100% dataset of all glaucoma procedures performed on Medicare Part B beneficiaries within the United States from 2005 to 2009. Fixed-effects regression model using Medicare Part B carrier data for all 50 states and the District of Columbia, controlling for time-invariant carrier-specific characteristics, national trends in glaucoma service volume, Medicare beneficiary population, number of ophthalmologists, and income per capita. Payment-volume elasticities, defined as the percent change in service volume per 1% change in Medicare payment, for laser trabeculoplasty (Current Procedural Terminology [CPT] code 65855), trabeculectomy without previous surgery (CPT code 66170), trabeculectomy with previous surgery (CPT code 66172), aqueous shunt to reservoir (CPT code 66180), laser iridotomy (CPT code 66761), and scleral reinforcement with graft (CPT code 67255). The payment-volume elasticity was nonsignificant for 4 of 6 procedures studied: laser trabeculoplasty (elasticity, -0.27; 95% confidence interval [CI], -1.31 to 0.77; P = 0.61), trabeculectomy without previous surgery (elasticity, -0.42; 95% CI, -0.85 to 0.01; P = 0.053), trabeculectomy with previous surgery (elasticity, -0.28; 95% CI, -0.83 to 0.28; P = 0.32), and aqueous shunt to reservoir (elasticity, -0.47; 95% CI, -3.32 to 2.37; P = 0.74). Two procedures yielded significant associations between Medicare payment and service volume. For laser iridotomy, the payment-volume elasticity was -1.06 (95% CI, -1.39 to -0.72; P payment, laser iridotomy service volume increased by 1.06%. For scleral reinforcement with graft, the payment-volume elasticity was -2.92 (95% CI, -5.72 to -0.12; P = 0.041): for every 1% decrease in CPT code 67255 payment, scleral reinforcement with graft service volume increased by 2.92%. This study calculated the association

Laser-induced nuclear physics and applications

International Nuclear Information System (INIS)

Ledingham, K.W.D.; Singhal, R.P.; McKenna, P.; Spencer, I.

2002-01-01

With a 1 ps pulse laser at 1 μm wavelength, He gas is ionised at about 3.10 14 W.cm -2 . As the intensity increases, the inert gases become multiple ionised and between 10 18 and 10 19 W.cm -2 photon induced nuclear reactions are energetically possible. Close to 10 21 W.cm -2 pion production can take place. At the very high intensities of 10 28 W.cm -2 , it can be shown that electron-positron pairs can be created from the vacuum. The authors review the applications of high intensity focused laser beams in particle acceleration, laser-induced fission and laser production of protons and neutrons. Exciting new phenomena are expected at intensities higher than 10 22 W.cm -2 , -) the oscillating electric field can affect directly the protons in exactly the same way as the electrons in the plasma, -) fusion reactions by direct laser acceleration of ions. (A.C.)

Supra-Tenon Capsule Implantation of the Ahmed Glaucoma Valve in Refractory Pediatric Glaucoma.

Science.gov (United States)

Elhefney, Eman M; Al-Sharkawy, Hossam T; Kishk, Hanem M

2016-09-01

To evaluate the efficacy of supra-Tenon capsule implantation of an Ahmed glaucoma valve (AGV) as a measure to decrease the fibrotic potential of the Tenon capsule on bleb formation and its subsequent effect on intraocular pressure (IOP) control in children with refractory glaucoma. Mansoura Ophthalmic Centre, Faculty of Medicine, Mansoura University, Egypt. A prospective interventional study. Twenty-two eyes of 12 children with refractory glaucoma underwent supra-Tenon capsule implantation of AGV. Ophthalmic examinations under general anesthesia including measurement of the corneal diameter and the IOP with Perkin's tonometer were performed preoperatively, on the first postoperative day, the first postoperative week, weekly for the first month, 2-weekly for the following 3 months, and monthly for at least 18 months. Postoperative complications and the number of glaucoma medications used preoperatively and postoperatively were recorded. The paired Student t test was used to compare preoperative and postoperative data. There were 12 eyes (54.6%) with refractory congenital glaucoma, 7 eyes (31.8%) with refractory pseudophakic glaucoma, and 3 eyes (13.6%) with refractory aphakic glaucoma. Patients included 10 male (83.3%) and 2 female (16.7%) children with a mean age of 16.3±9.7 months. The mean follow-up duration was 24.1±4.3 months. There was a statistically significant difference between the mean preoperative IOP (30.7±2.88 mm Hg) and the mean postoperative IOP (16.1±3.60 mm Hg) (t=16.22 and P=0.000, with a mean decrease in the IOP by 47.6%). The difference between the mean number of antiglaucoma medications before surgery (1.86±0.4) and after surgery (1.0±0.9) was also statistically significant (t=4.31 and P=0.000). Total success was achieved in 18 eyes (81.9%). Postoperative complications included tube exposure and slippage (10%), hypotony (10%), and hyphema (5%). Supra-Tenon capsule implantation of the AGV was successful in controlling the IOP with few

Five Common Glaucoma Tests

Science.gov (United States)

... About Us Donate In This Section Five Common Glaucoma Tests en Español email Send this article to ... year or two after age 35. A Comprehensive Glaucoma Exam To be safe and accurate, five factors ...

Pigment dispersion glaucoma induced by the chafing effect of intraocular lens haptics in Asian eyes.

Science.gov (United States)

Hong, Ying; Sun, Yan-Xiu; Qi, Hong; Zhou, Ji-Chao; Hao, Yan-Sheng

2013-03-01

To study the possible mechanism and treatment for pigment dispersion glaucoma (PDG) caused by single-piece acrylic (SPA) intraocular lens (IOL) ciliary sulcus fixation in Asian eyes. Patients referred for PDG caused by SPA IOL ciliary sulcus fixation to our hospital from April 2005 to June 2011 were included. The patients' general information, IOL type, interval between initial surgery and PDG occurrence, examination findings, antiglaucoma medicine regimen and surgical interventions were recorded. In total, six eyes from five Chinese patients were included in this study. The intraocular pressure (IOP) increased 19-30 days after cataract surgery and was not satisfactorily controlled with antiglaucoma medication. Dense pigmentation was deposited on the IOLs and on the anterior chamber angle. IOL haptic chafing was noted on the rear iris surface. IOL repositioning in the capsular bag was performed in three eyes and was combined with trabeculectomy in two eyes with progressive glaucoma. An IOL exchange with three-piece IOL ciliary sulcus fixation was performed in the other three eyes. Scanning electron microscopy of the explanted IOLs demonstrated a rough edge on the IOL haptics. SPA IOLs were not suitable for ciliary sulcus fixation. The chafing effect of the IOL haptics on the posterior iris pigment epithelium could induce PDG in Asian eyes. IOLs should be positioned in the capsular bag or a three-piece IOL should be used instead.

Angle closure glaucoma in congenital ectropion uvea.

Science.gov (United States)

Wang, Grace M; Thuente, Daniel; Bohnsack, Brenda L

2018-06-01

Congenital ectropion uvea is a rare anomaly, which is associated with open, but dysplastic iridocorneal angles that cause childhood glaucoma. Herein, we present 3 cases of angle-closure glaucoma in children with congenital ectropion uvea. Three children were initially diagnosed with unilateral glaucoma secondary to congenital ectropion uvea at 7, 8 and 13 years of age. The three cases showed 360° of ectropion uvea and iris stromal atrophy in the affected eye. In one case, we have photographic documentation of progression to complete angle closure, which necessitated placement of a glaucoma drainage device 3 years after combined trabeculotomy and trabeculectomy. The 2 other cases, which presented as complete angle closure, also underwent glaucoma drainage device implantation. All three cases had early glaucoma drainage device encapsulation (within 4 months) and required additional surgery (cycloablation or trabeculectomy). Congenital ectropion uvea can be associated with angle-closure glaucoma, and placement of glaucoma drainage devices in all 3 of our cases showed early failure due to plate encapsulation. Glaucoma in congenital ectropion uvea requires attention to angle configuration and often requires multiple surgeries to obtain intraocular pressure control.

Anesthetic Preconditioning as Endogenous Neuroprotection in Glaucoma

Directory of Open Access Journals (Sweden)

Tsung-Han Chou

2018-01-01

Full Text Available Blindness in glaucoma is the result of death of Retinal Ganglion Cells (RGCs and their axons. RGC death is generally preceded by a stage of reversible dysfunction and structural remodeling. Current treatments aimed at reducing intraocular pressure (IOP are ineffective or incompletely effective in management of the disease. IOP-independent neuroprotection or neuroprotection as adjuvant to IOP lowering in glaucoma remains a challenge as effective agents without side effects have not been identified yet. We show in DBA/2J mice with spontaneous IOP elevation and glaucoma that the lifespan of functional RGCs can be extended by preconditioning RGCs with retrobulbar lidocaine in one eye at four months of age that temporary blocks RGC axonal transport. The contralateral, PBS-injected eye served as control. Lidocaine-induced impairment of axonal transport to superior colliculi was assessed by intravitreal injection of cholera toxin B. Long-term (nine months effect of lidocaine were assessed on RGC electrical responsiveness (PERG, IOP, expression of relevant protein (BDNF, TrkB, PSD95, GFAP, Synaptophysin, and GAPDH and RGC density. While lidocaine treatment did not alter the age-related increase of IOP, TrkB expression was elevated, GFAP expression was decreased, RGC survival was improved by 35%, and PERG function was preserved. Results suggest that the lifespan of functional RGCs in mouse glaucoma can be extended by preconditioning RGCs in early stages of the disease using a minimally invasive treatment with retrobulbar lidocaine, a common ophthalmologic procedure. Lidocaine is inexpensive, safe and is approved by Food and Drug Administration (FDA to be administered intravenously.

Oculoplastic technique of connecting a glaucoma valve shunt to extraorbital locations in cases of severe glaucoma.

Science.gov (United States)

Rubin, Peter A D; Chang, Eli; Bernardino, Carlo Roberto; Hatton, Mark P; Dohlman, Claes H

2004-09-01

To describe a technique for inserting glaucoma shunts to the sinuses or the lacrimal sac as a means of lowering intraocular pressure in patients with refractory glaucoma associated with severe ocular surface disease. Nineteen patients with severe ocular surface disease necessitating a keratoprosthesis and with intractable glaucoma underwent placement of a modified Ahmed shunt to direct aqueous in the maxillary or ethmoid sinus or lacrimal sac. Intraocular pressure is presently well controlled without glaucoma medications in two thirds of patients. None of the patients had endophthalmitis. Established oculoplastic surgery techniques may be used to redirect aqueous to extraorbital locations and effectively lower intraocular pressure in patients with severe ocular surface disease and refractory glaucoma. This procedure has not been associated with endophthalmitis.

A noncontact intraocular pressure measurement device using a micro reflected air pressure sensor for the prediagnosis of glaucoma

International Nuclear Information System (INIS)

Kim, Kyoung Hwan; Kim, Byeong Hee; Seo, Young Ho

2012-01-01

This study investigates a novel, portable tonometer using a micro reflected air pressure sensor for the prediagnosis of glaucoma. Because glaucoma progresses slowly and is not painful, glaucoma patients require a portable prediagnosis system to periodically measure intraocular pressure at home. Conventionally, intraocular pressure is measured by an air-puff tonometer whereby the cornea is deformed by a short pulse of air pressure and the magnitude of the corneal deformation is measured by optic systems such as a combination of laser- and photodiodes. In this study, a micro reflected air pressure sensor was designed, fabricated, and tested in order to measure the magnitude of corneal deformation without optic systems. In an experimental study, artificial eyes with different internal pressures were fabricated and these pressures were measured by the aforementioned system. (paper)

Laser induced damage threshold on metallic surfaces during laser cleaning

CSIR Research Space (South Africa)

Labuschagne, K

2005-07-01

Full Text Available laser paint removal. Laser induced damage on 316L stainless steel was studied, with the target subjected to single and multiple pulse irradiations using a Q-switched Nd:YAG, with fluences between 0.15 and 11.8 J/cm2. Several different damage morphologies...

Changes of enzyme activities in lens after glaucoma trabecular resection

Directory of Open Access Journals (Sweden)

Jian-Ping Wang

2013-08-01

Full Text Available AIM: To observe the change of lens antioxidant enzyme activity after glaucoma trabecular resection. METHODS: Thirty-two eyes of sixteen New-Zealand rabbits(2.2-2.4kgwere divided into two groups. The left eyes of rabbits underwent standard glaucoma trabecular resection were treatment group, and the normal right eyes served as controls. Transparency of lenses was monitored by a slit-lamp biomicroscopy before and after glaucoma trabecular resection. The morphology of lens cells was observed under the light microscope.The activities of Na+-K+-ATPase,catalase(CAT, glutathion peroxidase(GSH-px, glutathione reductase(GR, superoxide dismutase(SODand content of malondialdehyde(MDAin lenses were detected six months after trabecular resection. RESULTS: Lenses were clear in both treatment group and normal control group during the six months after operation. The morphology and structure of lens cells were normal under the light microscope in both operation group and normal group. The activity of lens cells antioxidant enzyme activity were significantly decreased in operation group compared with control group, Na+-K+-ATPase declined by 20.97%, CAT declined by 16.36%, SOD declined by 4.46%, GR declined by 4.85%, GSH-px declined by 10.02%, and MDA increased by 16.31%. CONCLUSION: Glaucoma trabecular resection can induce the change of Na+-K+-ATPase, CAT, GSH-px, GR, SOD and MDA in lens of rabbit. Glaucoma filtration surgery for the occurrence of cataract development mechanism has important guiding significance.

Glaucoma

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Pediatric glaucoma: current perspectives

Directory of Open Access Journals (Sweden)

Marchini G

2014-05-01

Full Text Available Giorgio Marchini, Marco Toscani, Francesca Chemello Eye Clinic, Department of Neurological and Movement Sciences, University of Verona, Verona, Italy Abstract: “Childhood glaucoma” is a heterogeneous group of severe pediatric conditions often associated with significant visual loss and characterized by elevated intraocular pressure (IOP and optic-disk cupping. Successful IOP control is crucial but challenging and most often achieved surgically, with medical therapy playing a supportive role. There are many classifications of childhood glaucoma, but they can simply be divided into primary, in which a developmental abnormality of the anterior chamber angle only exists, and secondary, in which aqueous outflow is reduced due to independent mechanisms that secondarily impair the function of the filtration angle. The worldwide prevalence of childhood blindness ranges from 0.03% in high-income countries to 0.12% in undeveloped countries. The majority of cases do not have an identified genetic mutation and, where the mutation is known, the genes often account for only a small proportion of cases. Several pathogenetic mechanisms are known to contribute to the development of childhood glaucoma. Whatever the cause, it results in a reduced aqueous outflow at the level of the trabecular meshwork. Age of onset and magnitude of the elevated IOP largely determine the clinical manifestation the high variability of clinical manifestations. Glaucoma from any cause in a neonate and infant is characterized by the classic triad of epiphora, photophobia, and blepharospasm, and could be associated with eye enlargement (buphthalmos and Haab striae. The eye examination, usually performed under general anesthesia, includes: tonometry, anterior-segment examination, gonioscopy, corneal diameter and axial length measurement, dilated fundoscopy with optic-nerve-head evaluation. Medical therapy, considering the high frequency of side effects, is generally used as

The impact of available anti-glaucoma therapy on the volume and age profile of patients undergoing glaucoma filtration surgery.

LENUS (Irish Health Repository)

Keane, P A

2012-02-01

PURPOSE: To investigate whether new classes of glaucoma medication have influenced glaucoma filtration surgery over a 20-year period in the southeast region of Ireland. METHODS: All patients undergoing glaucoma filtration surgery between January 1986 and December 2005 in Waterford Regional Hospital were identified. The following data were recorded for each patient: age; sex; and type of filtration procedure. RESULTS: Over the 20-year study period two consultant ophthalmic surgeons performed a total of 760 glaucoma filtration procedures on patients aged over 20 years. The annual average number of glaucoma surgeries declined steadily, defined by availability of different topical anti-glaucoma medications, from an average of 23.75 surgeries per surgeon per year in the subperiod 1986-1995, to 21 in 1996, 20 in 1997, and 12.69 surgeries per surgeon per year in 1998-2005, these differences being statistically significant (general linear model, P<0.001). The age profile of patients did not change significantly over the course of the study period. CONCLUSIONS: The volume of patients requiring glaucoma filtration surgery under the care of two consultant ophthalmic surgeons decreased over the 20-year study period, an era in which three classes of anti-glaucoma medications were made available. However, an increase in the age profile of patients undergoing glaucoma filtration surgery during the same period was not observed. Further study is required to resolve whether introduction of the new topical anti-glaucoma medications has led to a real reduction in the demand for glaucoma filtration surgery, or has just led to the deferral of such a demand.

GENDER AND AGE FEATURES OF GLAUCOMA

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O. V. Makarenk

2014-02-01

Full Text Available Today, the definition “glaucoma” combines a number of eye pathologies that lead to irreversible blindness, and therefore is difficult disabling disease. Glaucoma occurs in people of working age, so this problem is not only medical, but also social, because it causes disability in substantial economic costs not only for individual patients, but also for the whole country – patients become unable to work. Gender features of glaucoma are also contradictory. In European literature the basic idea is that men are more likely to suffer from glaucoma than women. Such studies have not been conducted in the Podillya region of Ukraine, that makes impossible to design a reliable global data to estimate the prevalence of glaucoma in different age groups for persons living in Vinnitsa region. Therefore, the aim of the study was a retrospective analysis of medical records of patients in Eye Microsurgery Department of Vinnitsa Regional Clinical Hospital for the period 2008-2012 years for determining the gender and age characteristics. Materials and methods 1418 patients with primary open-angle glaucoma (841 men and 577 women aged 14 to 92 years (mean age 67,12 ± 7,64, which were treated in the Eye Microsurgery Department, took part in the study. For the purpose of the study they were divided into two groups: I – male patients with glaucoma, II – female patients with glaucoma. Each group was divided into 7 subgroups according to the ontogenesis scheme: A – teens, B – youth, C – I adulthood age, D – II adulthood age, E – elderly age, F – senily age and G – centenarians. Thus was allocated 12 research groups. Results The structure of the incidence of glaucoma is 59.31% in men and 40.69% in women. Incidence of glaucoma is highest in the IE group and is 34.98%. The group IIE incidence is lower – 35.32%. In the group D the incidence of glaucoma among men and women was very different (13.89% and 2.89%, respectively. It should also be noted

Differential protein expression in tears of patients with primary open angle and pseudoexfoliative glaucoma.

Science.gov (United States)

Pieragostino, Damiana; Bucci, Sonia; Agnifili, Luca; Fasanella, Vincenzo; D'Aguanno, Simona; Mastropasqua, Alessandra; Ciancaglini, Marco; Mastropasqua, Leonardo; Di Ilio, Carmine; Sacchetta, Paolo; Urbani, Andrea; Del Boccio, Piero

2012-04-01

Primary open angle (POAG) and pseudoexfoliative glaucoma (PXG) are the most common primary and secondary forms of glaucoma, respectively. Even though the patho-physiology, aqueous humor composition, risk factors, clinical features, therapy and drug induced ocular surface changes in POAG and PXG have been widely studied, to date information concerning tear protein characterization is lacking. Tears are a source of nourishment for ocular surface tissues and a vehicle to remove local waste products, metabolized drugs and inflammatory mediators produced in several ophthalmic diseases. In glaucoma, the proteomic definition of tears may provide insights concerning patho-physiology of the disease and ocular surface modifications induced by topical therapy. Our study aimed at characterizing protein patterns in tears of patients with medically controlled POAG and PXG. A comparative tears proteomic analysis by label-free LC-MS(E) highlighted differences in the expression of several proteins in the two glaucoma sub-types and control subjects, highlighting inflammation pathways expressed in both diseases. Results were independently reconfirmed by SDS-PAGE and linear MALDI-TOF MS, validating altered levels of Lysozyme C, Lipocalin-1, Protein S100, Immunoglobulins and Prolactin Inducible Protein. Moreover, we found a differential pattern of phosphorylated Cystatin-S that distinguishes the two pathologies. The most relevant results suggest that in both pathologies there may be active inflammation pathways related to the disease and/or induced by therapy. We show, for the first time, tear protein patterns expressed under controlled intraocular pressure conditions in POAG and PXG subjects. These findings could help in the understanding of molecular machinery underlying these ophthalmologic diseases, resulting in early diagnosis and more specific therapy.

Clinical findings following Ahmed Glaucoma Valve™ implantation in pediatric glaucoma

Directory of Open Access Journals (Sweden)

Amir Pirouzian

2008-03-01

Full Text Available Amir Pirouzian1, Joseph L Demer21Department of Ophthalmology, San Diego Children’s Hospital, San Diego, UCSD, San Diego, CA, USA; 2Department of Ophthalmology, Jules Stein Eye Institute, UCLA, Los Angeles, CA, USAPurpose: To describe clinical findings after Ahmed valve drainage implantation in children.Design: All records in one practice were reviewed to identify and describe clinical findings in all children who had undergone Ahmed Glaucoma ValveTM S2 model insertion for uncontrolled primary or secondary glaucoma.Results: A total of 6 patients were identified, ranging in age from 2–15 years. Mean follow-up time averaged from 2–5 years from the time of tube insertion. Three patients exhibited pupillary peaking towards the tube of the valve. All patients required additional surgery or additional medications to control intraocular pressure. Lenticular opacification near the tube site developed in one patient. Gradual tube extrusion was also noted in another two patients.Conclusion: Multiple clinical events follow the Ahmed valve insertion in children. Pupillary irregularity is the most commonly noted event in this series. To avoid or reduce the risk of this complication, additional or modification of surgical procedures could be considered. The mechanism of such occurrence will further be discussed.Keywords: Ahmed Glaucoma Valve, children, pediatric glaucoma

Level of agreement among Latin American glaucoma subspecialists on the diagnosis and treatment of glaucoma: results of an online survey.

Science.gov (United States)

Grigera, Daniel E; Mello, Paulo Augusto Arruda; Barbosa, Wilma Lelis; Casiraghi, Javier Fernando; Grossmann, Rodolfo Perez; Peyret, Alejo

2013-01-01

The aim of this research was to assess the level of agreement among glaucoma experts in Latin America on key practices related to treatment and diagnosis of glaucoma. An online questionnaire was sent to a multinational panel of glaucoma experts. The questionnaire contained 107 statements on the medical treatment (Part 1) and diagnosis (Part 2) of glaucoma, and was developed in Spanish and translated into English. Agreement was defined as >70% of respondents. Fifty participants from 14 countries completed the questionnaire. For the medical treatment of glaucoma, nearly all respondents (98% or greater) confirmed that medical treatment as first-line therapy is preferred to surgery, prostaglandin analogs are the medication of first choice for primary open-angle glaucoma (POAG), longitudinal monitoring of efficacy should include intraocular pressure, structural and functional status, as well as if patients' quality of life is impaired by the high cost of medication. For the diagnosis of glaucoma section, all respondents confirmed that, after initial examination, gonioscopy should be repeated over time, standard automated perimetry is the most important functional examination for diagnosis and monitoring of primary open-angle glaucoma, central corneal thickness is important in assessment of glaucoma, and computerized imaging tests help in clinical evaluation of optic disc. This survey shows a high level of agreement on most aspects of glaucoma diagnosis and treatment among Latin American glaucoma experts. Areas of disagreement highlight the need for further evidence or education. These findings will be useful for guiding future efforts to optimize glaucoma practice by clinicians in Latin America.

Level of agreement among Latin American glaucoma subspecialists on the diagnosis and treatment of glaucoma: results of an online survey

Directory of Open Access Journals (Sweden)

Daniel E. Grigera

2013-06-01

Full Text Available PURPOSE: The aim of this research was to assess the level of agreement among glaucoma experts in Latin America on key practices related to treatment and diagnosis of glaucoma. METHODS: An online questionnaire was sent to a multinational panel of glaucoma experts. The questionnaire contained 107 statements on the medical treatment (Part 1 and diagnosis (Part 2 of glaucoma, and was developed in Spanish and translated into English. Agreement was defined as >70% of respondents. RESULTS: Fifty participants from 14 countries completed the questionnaire. For the medical treatment of glaucoma, nearly all respondents (98% or greater confirmed that medical treatment as first-line therapy is preferred to surgery, prostaglandin analogs are the medication of first choice for primary open-angle glaucoma (POAG, longitudinal monitoring of efficacy should include intraocular pressure, structural and functional status, as well as if patients' quality of life is impaired by the high cost of medication. For the diagnosis of glaucoma section, all respondents confirmed that, after initial examination, gonioscopy should be repeated over time, standard automated perimetry is the most important functional examination for diagnosis and monitoring of primary open-angle glaucoma, central corneal thickness is important in assessment of glaucoma, and computerized imaging tests help in clinical evaluation of optic disc. CONCLUSIONS: This survey shows a high level of agreement on most aspects of glaucoma diagnosis and treatment among Latin American glaucoma experts. Areas of disagreement highlight the need for further evidence or education. These findings will be useful for guiding future efforts to optimize glaucoma practice by clinicians in Latin America.

An in-vitro morphological study of Q-switched neodymium/YAG laser trabeculotomy.

Science.gov (United States)

Venkatesh, S; Lee, W R; Guthrie, S; Cruickshank, F R; Foulds, W S; Quigley, R J; Bailey, R T

1986-02-01

Laser trabeculotomies produced by directing a pulsed neodymium/YAG laser beam at specimens of human anterior chamber angle obtained post mortem or after enucleation were studied by light microscopy and by scanning and transmission electron microscopy to assess the dimensions of the openings created in the trabecular meshwork, their penetrance to the canal of Schlemm, and the extent or absence of laser induced cellular damage in immediately adjacent tissue. A pulse duration of 40-50 ns at energy levels of around 30 mJ was used and the laser cavity carefully tuned to give a Gaussian spatial mode pattern. Openings in the trabecular meshwork typically of 100 microns in diameter and penetrating through to the canal of Schlemm could be regularly created with only minimal damage to adjacent tissue as judged by transmission electron microscopy. The information so gained may be useful in determining the parameters required for successful laser trabeculotomy as a treatment for primary open-angle glaucoma.

THE TREATMENT OF OPEN- AND NARROW-ANGLE GLAUCOMA

African Journals Online (AJOL)

1971-04-10

Apr 10, 1971 ... glaucoma will be considered: narrow-angle glaucoma. (acute glaucoma) and ... emotional or a physical crisis. The pain is in the distribu- .... ness, not increased pressure, haunts people suffering from glaucoma'.' The saga of ...

Railgun system using a laser-induced plasma armature

International Nuclear Information System (INIS)

Onozuka, M.; Oda, Y.; Azuma, K.

1996-01-01

Development of an electromagnetic railgun system that utilizes a laser-induced plasma armature formation has been conducted to investigate the application of the railgun system for high-speed pellet injection into fusion plasmas. Using the laser-induced plasma formation technique, the required breakdown voltage was reduced by one-tenth compared with that for the spark-discharged plasma. The railgun system successfully accelerated the laser-induced plasma armature by an electromagnetic force that accelerated the pellet. The highest velocity of the solid hydrogen pellets, obtained so far, was 2.6 km/sec using a 2m-long railgun. copyright 1996 American Institute of Physics

Railgun system using a laser-induced plasma armature

Science.gov (United States)

Onozuka, Masanori; Oda, Yasushi; Azuma, Kingo

1996-05-01

Development of an electromagnetic railgun system that utilizes a laser-induced plasma armature formation has been conducted to investigate the application of the railgun system for high-speed pellet injection into fusion plasmas. Using the laser-induced plasma formation technique, the required breakdown voltage was reduced by one-tenth compared with that for the spark-discharged plasma. The railgun system successfully accelerated the laser-induced plasma armature by an electromagnetic force that accelerated the pellet. The highest velocity of the solid hydrogen pellets, obtained so far, was 2.6 km/sec using a 2m-long railgun.

Comparison between visual field defect in pigmentary glaucoma and primary open-angle glaucoma.

Science.gov (United States)

Nilforushan, Naveed; Yadgari, Maryam; Jazayeri, Anisalsadat

2016-10-01

To compare visual field defect patterns between pigmentary glaucoma and primary open-angle glaucoma. Retrospective, comparative study. Patients with diagnosis of primary open-angle glaucoma (POAG) and pigmentary glaucoma (PG) in mild to moderate stages were enrolled in this study. Each of the 52 point locations in total and pattern deviation plot (excluding 2 points adjacent to blind spot) of 24-2 Humphrey visual field as well as six predetermined sectors were compared using SPSS software version 20. Comparisons between 2 groups were performed with the Student t test for continuous variables and the Chi-square test for categorical variables. Thirty-eight eyes of 24 patients with a mean age of 66.26 ± 11 years (range 48-81 years) in the POAG group and 36 eyes of 22 patients with a mean age of 50.52 ± 11 years (range 36-69 years) in the PG group were studied. (P = 0.00). More deviation was detected in points 1, 3, 4, and 32 in total deviation (P = 0.03, P = 0.015, P = 0.018, P = 0.023) and in points 3, 4, and 32 in pattern deviation (P = 0.015, P = 0.049, P = 0.030) in the POAG group, which are the temporal parts of the field. It seems that the temporal area of the visual field in primary open-angle glaucoma is more susceptible to damage in comparison with pigmentary glaucoma.

Ablative fractional laser enhances MAL-induced PpIX accumulation

DEFF Research Database (Denmark)

Haak, C S; Christiansen, K; Erlendsson, Andrés M

2016-01-01

BACKGROUND AND OBJECTIVES: Pretreatment of skin with ablative fractional laser enhances accumulation of topical provided photosensitizer, but essential information is lacking on the interaction between laser channel densities and pharmacokinetics. Hence our objectives were to investigate how...... (range 46-133min) induced fluorescence levels similar to curettage and 180min incubation. Furthermore, MAL 80 and 160mg/g induced similar fluorescence intensities in skin exposed to laser densities of 1, 2 and 5% (p>0.0537, 30-180min). CONCLUSION: MAL-induced protoporphyrin accumulation is augmented...... protoporphyrin accumulation was affected by laser densities, incubation time and drug concentration. METHODS: We conducted the study on the back of healthy male volunteers (n=11). Test areas were pretreated with 2940nm ablative fractional Er:YAG laser, 11.2mJ per laser channel using densities of 1, 2, 5, 10...

Glaucoma

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Full Text Available ... Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino ... To search for current job openings visit HHS USAJobs Home » NEI YouTube ...

Scanning the macula for detecting glaucoma

Directory of Open Access Journals (Sweden)

Viquar U Begum

2014-01-01

Full Text Available Background: With the advent of spectral domain optical coherence tomography (SDOCT, there has been a renewed interest in macular region for detection of glaucoma. However, most macular SDOCT parameters currently are thickness parameters which evaluate thinning of the macular layers but do not quantify the extent of area over which the thinning has occurred. We therefore calculated a new macular parameter, "ganglion cell complex surface abnormality ratio (GCC SAR" that represented the surface area over which the macular thickness was decreased. Purpose: To evaluate the ability of SAR in detecting perimetric and preperimetric glaucoma. Design: Retrospective image analysis. Materials and Methods: 68 eyes with perimetric glaucoma, 62 eyes with preperimetric glaucoma and 165 control eyes underwent GCC imaging with SDOCT. SAR was calculated as the ratio of the abnormal to total area on the GCC significance map. Statistical Analysis: Diagnostic ability of SAR in glaucoma was compared against that of the standard parameters generated by the SDOCT software using area under receiver operating characteristic curves (AUC and sensitivities at fixed specificities. Results: AUC of SAR (0.91 was statistically significantly better than that of GCC average thickness (0.86, P = 0.001 and GCC global loss volume (GLV; 0.88, P = 0.01 in differentiating perimetric glaucoma from control eyes. In differentiating preperimetric glaucoma from control eyes, AUC of SAR (0.72 was comparable to that of GCC average thickness (0.70, P > 0.05 and GLV (0.72, P > 0.05. Sensitivities at specificities of 80% and 95% of SAR were comparable (P > 0.05 for all comparisons to that of GCC average thickness and GLV in diagnosing perimetric and preperimetric glaucoma. Conclusion: GCC SAR had a better ability to diagnose perimetric glaucoma compared to the SDOCT software provided global GCC parameters. However, in diagnosing preperimetric glaucoma, the ability of SAR was similar to that of

Emission Characteristics of Laser-Induced Plasma Using Collinear Long and Short Dual-Pulse Laser-Induced Breakdown Spectroscopy (LIBS).

Science.gov (United States)

Wang, Zhenzhen; Deguchi, Yoshihiro; Liu, Renwei; Ikutomo, Akihiro; Zhang, Zhenzhen; Chong, Daotong; Yan, Junjie; Liu, Jiping; Shiou, Fang-Jung

2017-09-01

Collinear long and short dual-pulse laser-induced breakdown spectroscopy (DP-LIBS) was employed to clarify the emission characteristics from laser-induced plasma. The plasma was sustained and became stable by the long pulse-width laser with the pulse width of 60 μs under free running (FR) conditions as an external energy source. Comparing the measurement results of stainless steel in air using single-pulse LIBS (SP-LIBS) and DP-LIBS, the emission intensity was markedly enhanced using DP-LIBS. The temperature of plasma induced by DP-LIBS was maintained at a higher temperature under different gate delay time and short pulse-width laser power conditions compared with those measured using short SP-LIBS. Moreover, the variation rates of plasma temperatures measured using DP-LIBS were also lower. The superior detection ability was verified by the measurement of aluminum sample in water. The spectra were clearly detected using DP-LIBS, whereas it cannot be identified using SP-LIBS of short and long pulse widths. The effects of gate delay time and short pulse-width laser power were also discussed. These results demonstrate the feasibility and enhanced detection ability of the proposed collinear long and short DP-LIBS method.

Ahmed glaucoma valve implantation for refractory glaucoma after sequential failed trabeculectomy

Directory of Open Access Journals (Sweden)

Zhi-Qin Wu

2016-07-01

Full Text Available AIM: To evaluate the safety and efficacy of Ahmed glaucoma valve implantation for refractory glaucoma after sequential failed trabeculectomy. METHODS: Thirty-six patients(36 eyeswith prior failed sequential trabeculectomy who underwent Ahmed glaucoma valve implantation were included. The intraocular pressure(IOP, best corrected visual acuity(BCVAand complications were ovserved and all the patients were followed up at least for 12mo. RESULTS: Mean preoperative IOP was 35.20±7.28mmHg and reduced to 10.15±3.34, 11.23±3.56, 15.63±5.72, 17.17±5.47, 17.73±6.23,19.76±5.43mmHg at 1, 2wk, 1, 3, 6 and 12mo after surgery, which was significant different from the preoperative level(t=12.643, 11.837, 10.324, 8.839, 8.462, 8.046, all PZ=-0.420, P>0.05. At 12mo after operation, the complete success rate reached 78% and the conditional success rate reached 92%. There were 5 eyes complicated with shallow anterior chamber, 3 eye complicated with anterior chamber hemorrhage, which all recovered after additional treatments. Late complications included valve exposure and encapsulated cystic blebs around the plate. Severe corneal endothelium loss occurred in 1 patient. CONCLUSION: Ahmed glaucoma valve implantation is effective in reducing IOP at 1-year follow-up in refractory glaucoma patients with prior sequential failed trabeculectomy, but we should fully understand and attach great importance to all kinds of complications that may occur.

Nanotechnology and glaucoma: a review of the potential implications of glaucoma nanomedicine.

Science.gov (United States)

Kim, Nathaniel J; Harris, Alon; Gerber, Austin; Tobe, Leslie Abrams; Amireskandari, Annahita; Huck, Andrew; Siesky, Brent

2014-04-01

The purpose of this review is to discuss the evolution of nanotechnology and its potential diagnostic and therapeutic applications in the field of ophthalmology, particularly as it pertains to glaucoma. We reviewed literature using MEDLINE and PubMed databases with the following search terms: glaucoma, nanotechnology, nanomedicine, nanoparticles, ophthalmology and liposomes. We also reviewed pertinent references from articles found in this search. A brief history of nanotechnology and nanomedicine will be covered, followed by a discussion of the advantages and concerns of using this technology in the field of glaucoma. We will look at various studies concerning the development of nanomedicine, its potential applications in ocular drug delivery, diagnostic and imaging modalities and, surgical techniques. In particular, the challenges of assuring safety and efficacy of nanomedicine will be examined. We conclude that nanotechnology offers a novel approach to expanding diagnostic, imaging and surgical modalities in glaucoma and may contribute to the knowledge of disease pathogenesis at a molecular level. However, more research is needed to better elucidate the mechanism of cellular entry, the potential for nanoparticle cytotoxicity and the assurance of clinical efficacy.

Time-Resolved Spectroscopy Diagnostic of Laser-Induced Optical Breakdown

Directory of Open Access Journals (Sweden)

Christian G. Parigger

2010-01-01

Full Text Available Transient laser plasma is generated in laser-induced optical breakdown (LIOB. Here we report experiments conducted with 10.6-micron CO2 laser radiation, and with 1.064-micron fundamental, 0.532-micron frequency-doubled, 0.355-micron frequency-tripled Nd:YAG laser radiation. Characterization of laser induced plasma utilizes laser-induced breakdown spectroscopy (LIBS techniques. Atomic hydrogen Balmer series emissions show electron number density of 1017 cm−3 measured approximately 10 μs and 1 μs after optical breakdown for CO2 and Nd:YAG laser radiation, respectively. Recorded molecular recombination emission spectra of CN and C2 Swan bands indicate an equilibrium temperature in excess of 7000 Kelvin, inferred for these diatomic molecules. Reported are also graphite ablation experiments where we use unfocused laser radiation that is favorable for observation of neutral C3 emission due to reduced C3 cation formation. Our analysis is based on computation of diatomic molecular spectra that includes accurate determination of rotational line strengths, or Hönl-London factors.

Glaucoma evolution in patients with diabetes.

Science.gov (United States)

Apreutesei, Nicoleta Anton; Chiselita, D; Motas, O I

2014-01-01

Glaucoma and diabetes are two chronic diseases with a long suspected pathogenic relationship. Screening for glaucoma in patients with diabetes. A retrospective study on 92 eyes from 46 patients with primitive open angle glaucoma (POAG) (normal and hypertensive) and intraocular hypertension (OHT) receiving medication and/or surgery associated with diabetes mellitus (DM) (type I, type II, mixed) is presented. Participants were divided into two groups as following: 16 eyes with glaucoma and diabetic retinopathy changes (group 1) and 76 eyes with glaucoma and without diabetic retinopathy changes (group 2). The following parameters were analysed: ocular pressure (Goldmann aplanotonometry), perimeter development (computerized perimetry) and fundus condition (absence, presence or progression of diabetic retinopathy). In patients with glaucoma and diabetic retinopathy (8 patients) we found a mean difference between treated intraocular pressure (IOP) and IOP last untreated control of 4.95 mmHg; a depreciation of the MD by 4.18 dB and an average number of glaucoma medications used of 0.889 +/- 1.054. Predominant changes in proliferative diabetic retinopathy were mild. In patients with glaucoma in the absence of diabetic retinopathy, the average difference between untreated IOP and IOP under treatment at the last check-up was 1.63 mmHg, the MD depreciation was by 0.65 dB and the average number of glaucoma medications used was 0.795 +/- 0.978. No statistically significant differences in terms of initial and final pressure were found. No statistically significant differences in the evolution of changes in perimeter between the two groups were observed. The presence of non-proliferating diabetic retinopathy influenced (only marginally statistically) the glaucomatous disease progression. Large comparative prospective studies are needed for the long-term follow up.

Glaucoma in patients with uveitis.

OpenAIRE

Panek, W C; Holland, G N; Lee, D A; Christensen, R E

1990-01-01

The records of 100 patients (161 eyes) with uveitis were reviewed retrospectively to determine the prevalence of increased intraocular pressure, the forms of uveitis most commonly associated with glaucoma, and the forms that require specific glaucoma therapy. Secondary glaucoma was present in 23 patients (31 eyes): three of 24 patients with acute uveitis (three eyes, 12% of acute uveitis patients) and 20 of 76 patients with chronic uveitis (28 eyes, 26% of chronic uveitis patients). Eighteen ...

Glaucoma: Symptoms, Diagnosis, Treatment and Latest Research

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... of this page please turn Javascript on. Feature: Glaucoma Glaucoma: Symptoms, Diagnosis, Treatment and Latest Research Past Issues / Fall 2009 Table of Contents Symptoms and Diagnosis Glaucoma can develop in one or both eyes. Often ...

Efficacy and safety of intravitreal bevacizumab in eyes with neovascular glaucoma undergoing Ahmed glaucoma valve implantation: 2-year follow-up.

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Arcieri, Enyr S; Paula, Jayter S; Jorge, Rodrigo; Barella, Kleyton A; Arcieri, Rafael S; Secches, Danilo J; Costa, Vital P

2015-02-01

To evaluate the efficacy and safety of intravitreal bevacizumab (IVB) in eyes with neovascular glaucoma (NVG) undergoing Ahmed glaucoma valve (AGV) implantation. This was a multicentre, prospective, randomized clinical trial that enrolled 40 patients with uncontrolled neovascular glaucoma that had undergone panretinal photocoagulation and required glaucoma drainage device implantation. Patients were randomized to receive IVB (1.25 mg) or not during Ahmed valve implant surgery. Injections were administered intra-operatively, and 4 and 8 weeks after surgery. After a mean follow-up of 2.25 ± 0.67 years (range 1.5-3 years), both groups showed a significant decrease in IOP (p glaucoma undergoing Ahmed glaucoma valve implantation. There is a trend to slightly lower IOPs and number of medications with IVB use during AGV implantation for neovascular glaucoma. © 2014 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Childhood glaucoma surgery in the 21st Century

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Papadopoulos, M; Edmunds, B; Fenerty, C; Khaw, P T

2014-01-01

Most children with glaucoma will require surgery in their lifetime, often in their childhood years. The surgical management of childhood glaucoma is however challenging, largely because of its greater potential for failure and complications as compared with surgery in adults. The available surgical repertoire for childhood glaucoma has remained relatively unchanged for many years with most progress owing to modifications to existing surgery. Although the surgical approach to childhood glaucoma varies around the world, angle surgery remains the preferred initial surgery for primary congenital glaucoma and a major advance has been the concept of incising the whole of the angle (circumferential trabeculotomy). Simple modifications to the trabeculectomy technique have been shown to considerably minimise complications. Glaucoma drainage devices maintain a vital role for certain types of glaucoma including those refractory to other surgery. Cyclodestruction continues to have a role mainly for patients following failed drainage/filtering surgery. Although the prognosis for childhood glaucoma has improved significantly since the introduction of angle surgery, there is still considerable progress to be made to ensure a sighted lifetime for children with glaucoma all over the world. Collaborative approaches to researching and delivering this care are required, and this paper highlights the need for more high-quality prospective surgical trials in the management of the childhood glaucoma. PMID:24924446

The East London glaucoma prediction score: web-based validation of glaucoma risk screening tool

Science.gov (United States)

Stephen, Cook; Benjamin, Longo-Mbenza

2013-01-01

AIM It is difficult for Optometrists and General Practitioners to know which patients are at risk. The East London glaucoma prediction score (ELGPS) is a web based risk calculator that has been developed to determine Glaucoma risk at the time of screening. Multiple risk factors that are available in a low tech environment are assessed to provide a risk assessment. This is extremely useful in settings where access to specialist care is difficult. Use of the calculator is educational. It is a free web based service. Data capture is user specific. METHOD The scoring system is a web based questionnaire that captures and subsequently calculates the relative risk for the presence of Glaucoma at the time of screening. Three categories of patient are described: Unlikely to have Glaucoma; Glaucoma Suspect and Glaucoma. A case review methodology of patients with known diagnosis is employed to validate the calculator risk assessment. RESULTS Data from the patient records of 400 patients with an established diagnosis has been captured and used to validate the screening tool. The website reports that the calculated diagnosis correlates with the actual diagnosis 82% of the time. Biostatistics analysis showed: Sensitivity = 88%; Positive predictive value = 97%; Specificity = 75%. CONCLUSION Analysis of the first 400 patients validates the web based screening tool as being a good method of screening for the at risk population. The validation is ongoing. The web based format will allow a more widespread recruitment for different geographic, population and personnel variables. PMID:23550097

Laser-induced incandescence applied to dusty plasmas

NARCIS (Netherlands)

van de Wetering, F.M.J.H.; Oosterbeek, W.; Beckers, J.; Nijdam, S.; Kovacevic, E.; Berndt, J.

2016-01-01

This paper reports on the laser heating of nanoparticles (diameters ≤1 μm) confined in a reactive plasma by short (150 ps) and intense (~63 mJ) UV (355 nm) laser pulses (laser-induced incandescence, LII). Important parameters such as the particle temperature and radius follow from analysis of the

GLAUCOMA IN PSEUDOEXFOLIATION- CLINICAL PROSPECTIVE STUDY

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Balasubramanian M. Manickavelu

2018-01-01

Full Text Available BACKGROUND Pseudoexfoliation is one of the common cause of secondary open-angle glaucoma worldwide with a mean progression rate higher than primary open-angle glaucoma. In India, prevalence rate of pseudoexfoliation is around 2% (Hiller et al. In South India, the prevalence rate is 6% in >40 years of age as per Krishnadas et al in 2003. The aim of the study is to study the demographic aspects of pseudoexfoliation, the frequency of glaucoma in patients with pseudoexfoliation syndrome and to assess the treatment response in pseudoexfoliation syndrome. MATERIALS AND METHODS The study was conducted among 96 patients with pseudoexfoliation who attended OP Department of Ophthalmology, Government Tiruvannamalai Medical College and Hospital, Tiruvannamalai, from January 2017 to June 2017. Complete ocular examination with visual acuity, anterior segment examination, intraocular pressure, gonioscopy, fundus examination, central corneal thickness, visual field, ultrasound B scan and ultrasound biomicroscopy was done. RESULTS Incidence of glaucoma is more common in pseudoexfoliation and most of them have open angles. All patients with pseudoexfoliation should undergo complete glaucoma evaluation for early detection. Further ophthalmologist should focus on detection of pseudoexfoliation, since it is related to high risk of operative complication. CONCLUSION Incidence of glaucoma is more in pseudoexfoliation with most common bilateral presentation with open angles with recalcitrant intraocular pressure. Severity of optic nerve damage and with progression of field defects appeared to be more compared to primary open-angle glaucoma. Better response to combination drug therapy and surgical therapy than primary open-angle glaucoma.

Railgun system using a laser-induced plasma armature

Energy Technology Data Exchange (ETDEWEB)

Onozuka, M.; Oda, Y.; Azuma, K. [Mitsubishi Heavy Industries, Ltd., 3-3-1, Minatomirai, Nishi-ku, Yokohama 220-84 (Japan)

1996-05-01

Development of an electromagnetic railgun system that utilizes a laser-induced plasma armature formation has been conducted to investigate the application of the railgun system for high-speed pellet injection into fusion plasmas. Using the laser-induced plasma formation technique, the required breakdown voltage was reduced by one-tenth compared with that for the spark-discharged plasma. The railgun system successfully accelerated the laser-induced plasma armature by an electromagnetic force that accelerated the pellet. The highest velocity of the solid hydrogen pellets, obtained so far, was 2.6 km/sec using a 2m-long railgun. {copyright} {ital 1996 American Institute of Physics.}

Comparative Study Showing The Application Of Three Dimensional Oct And Ffa Correlation After Combined Bevacizumab/Laser And Triamcinolone/Laser In The Management Of Diabetic Macular Edema

International Nuclear Information System (INIS)

Helal, N.; Afahmoud, A.F.; Eliwa, T.F.; Omar, O.A.A.

2012-01-01

Purpose: to compare combined therapy by intravitreal triamicinolone acetonide and laser versus intravitreal bevacizumab and laser by three dimensional OCT in the management of diabetic macular edema regarding, the efficacy, duration of action, side effects, and complications of both regimens. Patients and methods: 40 eyes of 32 patients with type II diabetes mellitus, with clinically significant macular edema were enrolled into the study. They were divided equally into two groups, the first group was treated with intravitreal triamicinolone acetonide (4 mg/0.1 ml) followed 6 weeks later by focal Laser and the other group was treated by intravitreal bevacizumab (1.25 mg) followed 4 weeks later by focal Laser. Complete ophthalmological examination including BCVA, OCT and FFA were done preoperative and postoperative at 1, 3, 6, and 9 months. Results: the IVTA/Laser group showed an earlier improvement of BCVA by one line at the 3 month visit (p value 0.025 <0.05), compared to the IVA/Laser group that showed this change to be statistically significant at the 6 month visit (p value 0.048) with a one line improvement in BCVA. Regarding CMT and decrease of CMT than IVA/Laser although in both groups the improvement was transient, and relapses in both parameters occurred. There was a high incidence of cataract and steroid induced glaucoma in susceptible subjects in the IVTA/laser group than the IVA/Laser group. IVA/Laser may have a detrimental effect on FAZ integrity, and progression of the stage of diabetic retinopathy. Regarding mean change in CMT the IVTA/Laser has a stronger effect in reducing CMT, which is statistically significant at three months (p value <0.05). On the other hand IVA/Laser group, statistically significant change in mean CMT was at 1 month. Mean change in CMT between the 2 groups was not statistically significant throughout the study, although IVTA/Laser had a more powerful effect on the metric reduction of CMT, this difference was transient in both

Determinants of glaucoma awareness and knowledge in urban Chennai

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Sathyamangalam Ramesh

2009-01-01

Full Text Available Aim: To assess the awareness and knowledge levels about glaucoma and its determinants in an urban population of Chennai in south India. Materials and Methods: Chennai glaucoma study (CGS was a population based prevalence study to estimate the prevalence of glaucoma in a rural and urban south Indian population. A total of 3850 subjects aged 40 years or above participated in the urban arm of CGS. A systematic random sample of 1926 (50.0% subjects completed a questionnaire that assesses their awareness and knowledge level of glaucoma. Respondents "having heard of glaucoma" even before they were contacted/recruited for the study were defined as "aware" and respondents having some understanding of the eye disease were defined as "knowledgeable". Results: Overall 13.5% were aware of glaucoma, the age-gender adjusted rate for awareness was 13.3% (95% CI: 11.57 to 15.03. Two clinicians graded knowledge on glaucoma, based on the subject′s knowledge of risk factors, definitions and treatment aspects of glaucoma. Overall 8.7% had some knowledge about glaucoma. Among those who had knowledge 0.5% had good knowledge about glaucoma, 4% had fair knowledge and 4.2% had poor knowledge. We observed a very good agreement between the clinicians in grading knowledge (k =0.92. Determinants of glaucoma awareness and knowledge were higher levels of education, females, age, religion and family history of glaucoma. Conclusion: Awareness and knowledge about glaucoma was very low among the urban population of Chennai. We have found that younger subjects and men were less aware of glaucoma. Subjects with lower levels of education were less aware and knew less about glaucoma than their counterparts. The study findings stress the need for health education for effective prevention of blindness due to glaucoma.

Ahmed glaucoma valve in post-penetrating-keratoplasty glaucoma: A critically evaluated prospective clinical study

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Panda, Anita; Prakash, Vadivelu Jaya; Dada, Tanuj; Gupta, Anoop Kishore; Khokhar, Sudarshan; Vanathi, Murugesan

2011-01-01

Aim: The aim was to evaluate the outcome of Ahmed glaucoma valve (AGV) in post-penetrating-keratoplasty glaucoma (PKPG). Materials and Methods: In this prospective study, 20 eyes of 20 adult patients with post-PKPG with intraocular pressure (IOP) >21 mmHg, on two or more antiglaucoma medications, underwent AG (model FP7) implantation and were followed up for a minimum of 6 months. Absolute success was defined as 5 glaucoma managed by AGV implantation revealed a satisfactory outcome up to 6 months of follow-up. PMID:21586837

Comparative analysis of the results of various physical therapy techniques in the treatment of patients with primary open-angle glaucoma with chronic cerebral ischemia

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Lazarev М.S.

2012-06-01

Full Text Available

Aim of the study: to evaluate the effectiveness of the techniques of dynamic simultaneous transcranial magnetic therapy and resonance, and electrical stimulation, transcranial magnetic therapy and dynamic laser stimulation, magnetic simpatokorrektsii in the treatment of patients with primary open-angle glaucoma with chronic cerebral ischemia. Techniques. We observed 184 patients diagnosed with primary open-angle glaucoma who received different physical therapy techniques. Results. Patients treated with transcranial magnetic therapy and electrical stimulation or laser stimulation, in addition to improving visual function and improve the bioelectrical activity of the visual cortex, more pronounced than in other groups also observed the activation of the intraocular blood fow. Application of magnetic simpatokorrektsii allows for improvement of basic functional, electrophysiological and hemodynamic performance by reducing the activity of the sympathetic nervous system and reduce the vasopressor effect. Conclusion. Transcranial magnetic therapy in combination with electrical stimulation or laser stimulation is effective in the treatment of patients with POAG. In patients with primary open-angle glaucoma with chronic cerebral ischemia technique of magnetic sim-patokorrektsii compared with traditional methods of vasoactive therapy is more effective, which is manifested not only increase the visual functions, but also a decrease in cognitive impairment.

Pesquisaje de glaucoma

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Aldo Sigler Villanueva

1996-06-01

Full Text Available Se efectuó un pesquisaje de glaucoma mediante un chequeo masivo al 92,1 % (210 pacientes de la población mayor de 40 años de edad atendida en un consultorio del médico de la familia del municipio Morón. Se encontró que el 9,6 % (20 pacientes presentaban cifras de tensión ocular por encima de los valores normales, así como 3 pacientes que tenían tensión ocular normal, pero con excavaciones de papilas sospechosas y 2 pacientes con antecedentes familiares de glaucoma, los cuales se enviaron a la consulta especializada del Hospital General Provincial Docente de Moron para confirmar o no el diagnóstico.The 92,1 % (210 patients of the population over 40 years treated at a family physician's office in Morón municipality took part in a glaucoma mass screening. It was found that 9,6 % (20 patients showed figures of ocular tension exceeding normal values and that 3 patients had normal ocular tension but presented suspicious excavation of the optic disc. Two patients having glaucoma family history were referred to the specialist at the Provincial General Teaching Hospital of Moron in order to confirm the diagnosis.

Laser-induced grating in ZnO

DEFF Research Database (Denmark)

Ravn, Jesper N.

1992-01-01

A simple approach for the calculation of self-diffraction in a thin combined phase and amplitude grating is presented. The third order nonlinearity, the electron-hole recombination time, and the ambipolar diffusion coefficient in a ZnO crystal are measured by means of laser-induced self-diffracti......A simple approach for the calculation of self-diffraction in a thin combined phase and amplitude grating is presented. The third order nonlinearity, the electron-hole recombination time, and the ambipolar diffusion coefficient in a ZnO crystal are measured by means of laser-induced self...

New pharmacotherapy for the treatment of glaucoma.

Science.gov (United States)

Schehlein, Emily M; Novack, Gary; Robin, Alan L

2017-12-01

Glaucoma is the second leading cause of blindness in the world and current pharmacotherapies for glaucoma have remained relatively unchanged (with the exception of fixed combinations of previously available medications) since the mid-1990s with the development of prostaglandin analogues. Now, with both new formulations and new classes of medications with novel mechanisms of action, the medical therapy of glaucoma may be heralding a new dawn in medical management. Areas covered: This review outlines new topical therapies for intraocular pressure (IOP) lowering treatment, in addition to new formulations, preservative-free options, and advances in glaucoma medical therapy delivery. We performed a comprehensive search for published studies for glaucoma medical therapy using the electronic database PubMed. A manual search for each therapy or delivery system was also performed. Expert commentary: These advances in glaucoma therapy have the potential to overcome many barriers to glaucoma's medical care, particularly in terms of adherence. However, both time and research are needed to prove the relative efficacy and safety of these new pharmacotherapies and products, helping us decide their role in the treatment of elevated intraocular pressure. We are hopeful that these new developments in therapy may bring more options for glaucoma medical therapy.

Assessment of β-zone peripapillary atrophy by optical coherence tomography and scanning laser ophthalmoscopy imaging in glaucoma patients

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Seidensticker F

2014-06-01

Full Text Available Florian Seidensticker,1,* Lukas Reznicek,2,* Thomas Mann,2 Irene Hübert,2 Anselm Kampik,2 Michael Ulbig,2 Christoph Hirneiss,2 Aljoscha S Neubauer,2 Marcus Kernt2 1Department of Ophthalmology, Hannover Medical School, Hannover, Germany; 2Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany  *These authors have contributed equally to this work Purpose: To assess β-zone peripapillary atrophy (β-PPA using spectral domain optical coherence tomography (SD-OCT, scanning laser ophthalmoscopy (SLO, and fundus autofluorescence (FAF imaging in patients with primary open-angle glaucoma with advanced glaucomatous visual field defects. Methods: A consecutive, prospective series of 82 study eyes with primary open-angle glaucoma were included in this study. All study participants underwent a full ophthalmic examination followed by SD-OCT, wide-field SLO, and FAF imaging of the optic nerve head and the peripapillary region. Results: Eighty-four glaucomatous eyes were included in our prospective study. Correlation analyses for horizontally and vertically obtained β-PPA for all three imaging modalities (color SLO, FAF, and SD-OCT revealed highest correlations between FAF and color SLO (Pearson correlation coefficient: 0.904 [P<0.001] for horizontal β-PPA and 0.786 [P<0.001] for vertical β-PPA. Bland–Altman plotting revealed highest agreements between color SLO and FAF, with −2.1 pixels ±1.96 standard deviation (SD for horizontal β-PPA, SD: 10.5 pixels and 2.4 pixels ±1.96 SD for vertical β-PPA. Conclusion: β-PPA can be assessed using en-face SLO and cross-sectional SD-OCT imaging. Correlation analyses revealed highest correlations between color SLO and FAF imaging, while correlations between SLO and SD-OCT were weak. A more precise structural definition of β-PPA is needed. Keywords: fundus autofluorescence, FAF, OCT, SD-OCT, SLO, glaucomatous optic neuropathy

Combined Phacoemulsification and Ahmed Glaucoma Drainage Implant Surgery for Patients With Refractory Glaucoma and Cataract.

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Valenzuela, Felipe; Browne, Andrew; Srur, Miguel; Nieme, Carlos; Zanolli, Mario; López-Solís, Remigio; Traipe, Leonidas

2016-02-01

To examine the indications, safety, efficacy, and complications of combined phacoemulsification and Ahmed glaucoma drainage implant surgery. A retrospective case review of 35 eyes (31 patients) subjected to combined phacoemulsification and Ahmed glaucoma drainage implant surgery. Demographic characteristics of the study population, indications for combined surgery, and operative and postoperative complications were recorded. Visual acuity, intraocular pressure (IOP), and number of glaucoma medications were evaluated preoperatively and postoperatively. Complete success was defined as IOP ≤ 21 mm Hg without medication, qualified success if IOP ≤ 21 mm Hg with ≥ 1 medications, and failure if IOP>21 mm Hg or ≤ 5 mm Hg on ≥ 2 consecutive visits. Mean follow-up was 29.5 months (range, 6 to 87 mo). The most common indication for combined surgery was a history of prior failed trabeculectomy (60%). Postoperative visual acuity improved in 30 of 35 eyes (85%) (PAhmed glaucoma drainage implant surgery seems to be a safe and effective surgical option, providing good visual rehabilitation and control of IOP for patients with refractory glaucoma and cataract.

A case of WAGR syndrome in association with developmental glaucoma requiring bilateral Baerveldt glaucoma implants and subsequent tube repositioning

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Akagi T

2015-06-01

Full Text Available Tadamichi Akagi, Munemitsu Yoshikawa, Hideo Nakanishi, Nagahisa Yoshimura Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan Abstract: Glaucoma drainage device implantation is efficacious for the treatment of pediatric glaucoma patients when multiple angle surgeries fail. However, tube touching of the corneal endothelium is one of the major postoperative complications to deal with. A 15-month-old male patient with Wilms’ tumor, aniridia, genitourinary anomalies, and mental retardation (WAGR syndrome was diagnosed with bilateral developmental glaucoma. He underwent Baerveldt glaucoma implant (BGI surgeries in both eyes after multiple failed trabeculotomies. The tube in his right eye was touching the cornea 15 months after BGI surgery. To avoid corneal endothelium damage, BGI tube repositioning with scleral fixation was performed without serious complications. The bilateral BGI surgeries achieved successful intraocular pressure reduction for over 2 years and tube repositioning with scleral fixation of BGI tube was successful for BGI tube malposition. Although careful attention to intraocular pressure and tube malposition is essential after glaucoma drainage device implantation, especially in pediatric cases, BGI surgery is effective in the management of developmental glaucoma following unsuccessful angle surgeries. Keywords: Baerveldt glaucoma implant, developmental glaucoma, WAGR syndrome, tube repositioning, glaucoma drainage device

New Tool to Predict Glaucoma

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... In This Section A New Tool to Predict Glaucoma email Send this article to a friend by ... Close Send Thanks for emailing that article! Tweet Glaucoma can be difficult to detect and diagnose. Measurement ...

Does Your Child Have Glaucoma?

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... Donate In This Section Does Your Child Have Glaucoma? email Send this article to a friend by ... a pediatric ophthalmologist. Signs and Symptoms of Childhood Glaucoma What to watch for in children under the ...

Does Marijuana Help Treat Glaucoma?

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... time, reducing side vision. It sometimes leads to blindness. One cause of optic nerve damage in glaucoma ... high doses, can cause problems with short-term memory and concentration. As scientists learn more about glaucoma, ...

Propionibacterium acnes endophthalmitis in Ahmed glaucoma valve.

Science.gov (United States)

Gutiérrez-Díaz, E; Montero-Rodríguez, M; Mencía-Gutiérrez, E; Fernández-González, M C; Pérez-Blázquez, E

2001-01-01

To report a case of Propionibacterium acnes endophthalmitis in a patient with an Ahmed glaucoma valve. A nine-year-old boy with bilateral congenital glaucoma, with an Ahmed glaucoma valve implanted in the left eye, had recurrent conjunctival dehiscence and endophthalmitis. Vitreous cultures demonstrated the presence of Propionibacterium acnes. This is the first reported case of Propionibacterium acnes endophthalmitis in an Ahmed glaucoma valve and the second one in a glaucoma drainage device. We strongly recommend using a patch graft to prevent and treat tube exposure. Conjunctival grafts may be useful to close the conjunctiva when there is marked scarring to prevent patch exposure and melting or extrusion.

Movement of retinal vessels toward the optic nerve head after increasing intraocular pressure in monkey eyes with experimental glaucoma.

Science.gov (United States)

Kuroda, Atsumi; Enomoto, Nobuko; Ishida, Kyoko; Shimazawa, Masamitsu; Noguchi, Tetsuro; Horai, Naoto; Onoe, Hirotaka; Hara, Hideaki; Tomita, Goji

2017-09-01

A shift or displacement of the retinal blood vessels (RBVs) with neuroretinal rim thinning indicates the progression of glaucomatous optic neuropathy. In chronic open angle glaucoma, individuals with RBV positional shifts exhibit more rapid visual field loss than those without RBV shifts. The retinal vessels reportedly move onto the optic nerve head (ONH) in response to glaucoma damage, suggesting that RBVs are pulled toward the ONH in response to increased cupping. Whether this phenomenon only applies to RVBs located in the vicinity or inside the ONH or, more generally, to RBVs also located far from the ONH, however, is unclear. The aim of this study was to evaluate the movement of RBVs located relatively far from the ONH edge after increasing intraocular pressure (IOP) in an experimental monkey model of glaucoma. Fundus photographs were obtained in 17 monkeys. High IOP was induced in the monkeys by laser photocoagulation burns applied uniformly with 360° irradiation around the trabecular meshwork of the left eye. The right eye was left intact and used as a non-treated control. Considering the circadian rhythm of IOP, it was measured in both eyes of each animal at around the same time-points. Then, fundus photographs were obtained. Using Image J image analysis software, an examiner (N.E.) measured the fundus photographs at two time-points, i.e. before laser treatment (time 1) and the last fundus photography after IOP elevation (time 2). The following parameters were measured (in pixels): 1) vertical diameter of the ONH (DD), 2) distance from the ONH edge to the first bifurcation point of the superior branch of the central retinal vein (UV), 3) distance from the ONH edge to the first bifurcation point of the inferior branch of the central retinal vein (LV), 4) ONH area, and 5) surface area of the cup of the ONH. We calculated the ratios of UV to DD (UV/DD), LV to DD (LV/DD), and the cup area to disc area ratio (C/D). The mean UV/DD at time 1 (0.656 ± 0.233) was

Late-onset endophthalmitis secondary to exposed glaucoma tube implant in a rare case of paediatric glaucoma.

Science.gov (United States)

Ranganath, Akshatha; Hashim, Adnan

2011-01-01

Glaucoma drainage implants (GDIs) are used to treat paediatric glaucoma resistant to conventional medical and surgical treatment, achieving good intraocular pressure (IOP) control and long-term success. Late endophthalmitis is a rare complication that may develop following GDI surgery. A 17-year-old male presented with acute endophthalmitis 2 years after Ahmed glaucoma valve implantation with pericardial patch graft for management of refractory glaucoma secondary to congenital ectropion uveae. The glaucoma tube was exposed due to erosion of the overlying conjunctiva with no visible pericardial graft. After control of active infection, he underwent tube revision surgery whereby the exposed tube was retained and repatched with a double-thickness pericardial patch graft. He did well following surgery with good control of IOP and restoration of vision. Conjunctival dehiscence with graft melting over the GDI tube presented a major risk factor for endophthalmitis. Prompt surgical revision of an exposed tube is highly recommended to avoid ocular morbidity.

Late-Onset Endophthalmitis Secondary to Exposed Glaucoma Tube Implant in a Rare Case of Paediatric Glaucoma

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Akshatha Ranganath

2011-01-01

Full Text Available Glaucoma drainage implants (GDIs are used to treat paediatric glaucoma resistant to conventional medical and surgical treatment, achieving good intraocular pressure (IOP control and long-term success. Late endophthalmitis is a rare complication that may develop following GDI surgery. A 17-year-old male presented with acute endophthalmitis 2 years after Ahmed glaucoma valve implantation with pericardial patch graft for management of refractory glaucoma secondary to congenital ectropion uveae. The glaucoma tube was exposed due to erosion of the overlying conjunctiva with no visible pericardial graft. After control of active infection, he underwent tube revision surgery whereby the exposed tube was retained and repatched with a double-thickness pericardial patch graft. He did well following surgery with good control of IOP and restoration of vision. Conjunctival dehiscence with graft melting over the GDI tube presented a major risk factor for endophthalmitis. Prompt surgical revision of an exposed tube is highly recommended to avoid ocular morbidity.

Glaucoma

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Full Text Available ... Amblyopia Animations Blindness Cataract Convergence Insufficiency Diabetic Eye Disease Dilated Eye Exam Dry Eye For Kids Glaucoma Healthy Vision Tips Leber Congenital Amaurosis Low Vision Refractive Errors Retinopathy of Prematurity ...

Structure, function and progression analysis in glaucoma : a study with scanning laser polarimetry

NARCIS (Netherlands)

Mai, Thê' Anh

2008-01-01

Glaucoma is currently a serious global challenge. It is the second leading cause of blindness worldwide after cataract, and accounts for up to 12.3 % of all blindness (i.e., approximately 4.5 million people). As the size of the world population aged 50 years or older increases, the number of people,

Resource Planning in Glaucoma: A Tool to Evaluate Glaucoma Service Capacity.

Science.gov (United States)

Batra, Ruchika; Sharma, Hannah E; Elaraoud, Ibrahim; Mohamed, Shabbir

2017-12-28

The National Patient Safety Agency (2009) publication advising timely follow-up of patients with established glaucoma followed several reported instances of visual loss due to postponed appointments and patients lost to follow-up. The Royal College of Ophthalmologists Quality Standards Development Group stated that all hospital appointments should occur within 15% of the intended follow-up period. To determine whether: 1. Glaucoma follow-up appointments at a teaching hospital occur within the requested time 2. Appointments are requested at appropriate intervals based on the NICE Guidelines 3. The capacity of the glaucoma service is adequate Methods: A two-part audit was undertaken of 98 and 99 consecutive patients respectively attending specialist glaucoma clinics. In the first part, the reasons for delayed appointments were recorded. In the second part the requested follow-up was compared with NICE guidelines where applicable. Based on the findings, changes were implemented and a re-audit of 100 patients was carried out. The initial audit found that although clinical decisions regarding follow-up intervals were 100% compliant with NICE guidelines where applicable, 24% of appointments were delayed beyond 15% of the requested period, due to administrative errors and inadequate capacity, leading to significant clinical deterioration in two patients. Following the introduction of an electronic appointment tracker and increased clinical capacity created by extra clinics and clinicians, the re-audit found a marked decrease in the percentage of appointments being delayed (9%). This audit is a useful tool to evaluate glaucoma service provision, assist in resource planning for the service and bring about change in a non-confrontational way. It can be widely applied and adapted for use in other medical specialities.

Evaluation of ExPress glaucoma filtration device in Indian patients with advanced glaucoma

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Dewang Angmo

2015-01-01

Full Text Available ExPress glaucoma filtration device (GFD has recently become available in India as a surgical option for glaucoma patients. We retrospectively evaluated the outcome of ExPress GFD in 12 eyes with advanced glaucoma with intraocular pressures (IOPs not controlled on maximal tolerable medical therapy. The mean preoperative IOP of 29.58 ± 7.13 mmHg decreased to 17.0 ± 2.67 and 17.40 ± 0.89 mmHg at 6 and 12 months after surgery. Absolute success (IOP ≤ 18 mmHg, with no additional glaucoma medications was achieved in eight cases (66.7% and qualified success (IOP ≤ 18 mmHg, with additional glaucoma medications in two cases (16.7% at 1-year after surgery. Early intervention was needed in 4 patients; two underwent anterior chamber reformation while the other two required needling. Two patients required resurgery. There was no significant change in the best corrected visual acuity postoperatively (P = 0.37. ExPress GFD does not seem to offer a benefit over standard trabeculectomy in patients with advanced glaucomatous disease in terms of IOP control or complication rate. However, due to the small sample size with a heterogeneous mixture of primary and secondary glaucoma′s, we await further studies with a larger sample size and long-term follow-up, to see how the device performs.

Evaluation of Ocular Surface Disease in Patients with Glaucoma

Science.gov (United States)

Mathews, Priya M.; Ramulu, Pradeep Y.; Friedman, David S.; Utine, Canan A.; Akpek, Esen K.

2013-01-01

Purpose To evaluate the subjective and objective measures of ocular surface disease in patients with glaucoma. Design Cross-sectional study. Participants Sixty-four glaucoma subjects with bilateral visual field (VF) loss and 59 glaucoma suspects with normal VFs. Methods Consecutive patients were recruited prospectively from the Wilmer Eye Institute Glaucoma Clinic. Main Outcome Measures Tear film breakup time (TBUT), corneal staining score (0–15), and Schirmer’s test results were included as objective metrics, whereas the Ocular Surface Disease Index (OSDI) questionnaire was administered to assess symptoms. Total OSDI score, vision-related subscore (derived from questions about vision and task performance), and discomfort-related subscore (derived from questions about ocular surface discomfort) were calculated for each subject. Results Seventy-five percent (48/64) of glaucoma subjects and 41% (24/59) of glaucoma suspects were receiving topical medications. The corneal staining grade was greater in glaucoma subjects than in glaucoma suspects (6.4 vs. 4.1; P0.20 for both). Multivariate regression models showed that topical glaucoma therapy burden was associated with a significantly higher total corneal staining grade (β, +0.9 for each additional glaucoma drop; 95% confidence interval [CI], 0.5–1.3; P0.20 for both). Glaucoma subjects had significantly higher total OSDI scores than glaucoma suspects (16.7 vs. 7.9; Pglaucoma group (11.1 vs. 3.3; Pglaucoma therapy burden was not associated with higher total OSDI score or vision- or discomfort-related subscore (P>0.20 for all). Conclusions Glaucoma is associated with significant ocular surface disease, and topical glaucoma therapy burden seems predictive of corneal staining severity. However, OSDI is a poor metric for capturing ocular surface disease in glaucoma because symptoms seem to be related largely to VF loss. PMID:23714318

Effect of benzalkonium chloride-free latanoprost ophthalmic solution on ocular surface in patients with glaucoma

OpenAIRE

Walimbe T; Chelerkar V; Bhagat P; Joshi A; Raut A

2016-01-01

Tejaswini Walimbe,1 Vidya Chelerkar,2 Purvi Bhagat,3 Abhijeet Joshi,4 Atul Raut4 1Walimbe Eye Clinic, 2PBMA’s H.V. Desai Eye Hospital, Pune, 3Glaucoma Clinic, M and J Western Regional Institute of Ophthalmology, Civil Hospital, Ahmedabad, 4Clinical Research Department, Sun Pharma Advanced Research Company Ltd., Mumbai, India Introduction: Benzalkonium chloride (BAK), included as a preservative in many topical treatments for glaucoma, induces significant toxicity and alters tear br...

Driving patterns in older adults with glaucoma.

Science.gov (United States)

van Landingham, Suzanne W; Hochberg, Chad; Massof, Robert W; Chan, Emilie; Friedman, David S; Ramulu, Pradeep Y

2013-02-21

The ability to drive is important for ensuring quality of life for many older adults. Glaucoma is prevalent in this age group and may affect driving. The purpose of this study is to determine if glaucoma and glaucomatous visual field (VF) loss are associated with driving cessation, limitations, and deference to another driver in older adults. Cross-sectional study. Eighty-one glaucoma subjects and 58 glaucoma suspect controls between age 60 and 80 reported if they had ceased driving, limited their driving in various ways, or preferred another to drive. Twenty-three percent of glaucoma subjects and 6.9% of suspects had ceased driving (p = 0.01). Glaucoma subjects also had more driving limitations than suspects (2.0 vs. 1.1, p = 0.007). In multivariable models, driving cessation was more likely for glaucoma subjects as compared to suspects (OR = 4.0; 95% CI = 1.1-14.7; p = 0.03). The odds of driving cessation doubled with each 5 decibel (dB) decrement in the better-eye VF mean deviation (MD) (OR = 2.0; 95% CI = 1.4-2.9; p driving limitations (OR = 4.7; 95% CI = 1.3-16.8; p = 0.02). The likelihood of reporting more limitations increased with the VF loss severity (OR = 1.6 per 5 dB decrement in the better-eye VF MD; 95% CI = 1.1-2.4; p = 0.02). Neither glaucoma nor VF MD was associated with other driver preference (p > 0.1 for both). Glaucoma and glaucomatous VF loss are associated with greater likelihood of driving cessation and greater limitation of driving in the elderly. Further prospective study is merited to assess when and why people with glaucoma change their driving habits, and to determine if their observed self-regulation of driving is adequate to ensure safety.

Stage of visual field loss and age at diagnosis in 1988 patients with different glaucomas: implications for glaucoma screening and driving ability.

Science.gov (United States)

Gramer, Gwendolyn; Gramer, Eugen

2018-04-01

To compare stage of visual field loss (VFL) and age at diagnosis between patients with different types of glaucoma with regard to glaucoma screening and driving ability. In a cross-sectional study of 1988 consecutive patients with different types of glaucoma VFL at diagnosis and age at diagnosis were assessed. Patients with binocular advanced or severe VFL were classified unable, patients with no VFL in one eye and VFL I-V (Aulhorn classification) in the other eye able, all other constellations questionably able to drive. There were significant differences in age at diagnosis between different glaucomas and between patients with different stages of VFL at diagnosis. Age-related assessment of VFL at diagnosis in normal tension glaucoma (NTG) compared to primary open-angle glaucoma (POAG) showed that NTG is not a disease of the elderly but a disease with late diagnosis at severe VFL. In POAG a solely age-related glaucoma screening, e.g. from the age of 50 years, does not sufficiently lead to diagnosis at an early stage of the disease. In POAG solely based on binocular VFL 11.5% of patients were judged unable, 29.2% questionably able to drive, in NTG 19.6%/43.1%, pigmentary glaucoma 16%/22%, pseudoexfoliation glaucoma 9.1%/16.7%, and in primary angle-closure glaucoma 14.6%/30%. Depending on type of glaucoma more than 50% of patients require counselling regarding safe driving as part of clinical care. A disease-specific, age-related perimetric examination considering additional risk factors like family history of glaucoma is essential for early detection of glaucoma and road safety.

Glaucoma Drainage Device Erosion Following Ptosis Surgery.

Science.gov (United States)

Bae, Steven S; Campbell, Robert J

2017-09-01

To highlight the potential risk of glaucoma drainage device erosion following ptosis surgery. Case report. A 71-year-old man underwent uncomplicated superotemporal Ahmed glaucoma valve implantation in the left eye in 2008. Approximately 8 years later, the patient underwent bilateral ptosis repair, which successfully raised the upper eyelid position. Three months postoperatively, the patient's glaucoma drainage implant tube eroded through the corneal graft tissue and overlying conjunctiva to become exposed. A graft revision surgery was successfully performed with no further complications. Caution and conservative lid elevation may be warranted when performing ptosis repair in patients with a glaucoma drainage implant, and patients with a glaucoma implant undergoing ptosis surgery should be followed closely for signs of tube erosion.

Monitoring dynamics of aqueous humor in glaucoma

International Nuclear Information System (INIS)

Vyborny, P.; Hornova, J.

1985-01-01

Aqueous humor dynamics was observed in patients treated for glaucoma. Aqueous flow was measured using the radionuclide method of contact application of 22 NaCl and the detection of gamma radiation with external detectors. The sample of 184 eyes was divided into three groups: open-angle glaucoma with therapy, open-angle glaucoma without therapy and angle-closure glaucoma 47 eyes were used as controls. Changes were observed in 22 Na outflow half-time in dependence on the duration of the disease, therapy, intraocular pressUre and changes in the perimeter. The new technique has been fully proven in practice, is a contribution to the diagnosis of glaucoma and an indicator of the compensation of the disease. (author)

Inter-eye comparison of retinal oximetry and vessel caliber between eyes with asymmetrical glaucoma severity in different glaucoma subtypes

Directory of Open Access Journals (Sweden)

Cheng CS

2016-07-01

Full Text Available Clarissa Shu Ming Cheng,1,2 Yi Fang Lee,2 Charles Ong,3 Zhu Li Yap,2 Andrew Tsai,2 Aditi Mohla,2 Monisha E Nongpiur,4 Tin Aung,2,4 Shamira A Perera2,4 1Department of Ophthalmology, Tan Tock Seng Hospital, 2Department of Ophthalmology, Singapore National Eye Centre, 3Yong Loo Lin School of Medicine, National University of Singapore, 4Singapore Eye Research Institute, Singapore National Eye Centre, Singapore Background: To compare retinal vessel oxygenation and vessel caliber in primary angle-closure glaucoma (PACG, primary open-angle glaucoma (POAG, normal-tension glaucoma (NTG, and normal controls, as well as between eyes of asymmetrical glaucoma severity.Methods: This was a prospective, cross-sectional study. The 159 subjects (PACG, n=39; POAG, n=41; NTG, n=41; normal controls, n=38 underwent retinal oxygen saturation measurements using the Oxymap T1 Retinal Oximeter, optical coherence tomography, and Humphrey visual field testing. Retinal oxygen saturation and vessel diameter were compared between the glaucoma groups and normal controls, as well as between eyes of asymmetrical glaucoma severity. Kruskal–Wallis test was performed for comparison among different subtypes of glaucoma. Wilcoxon signed-rank test was used to compare the inter-eye differences.Results: Compared to normal controls, arteriolar oxygen saturation was increased in PACG eyes (P=0.048 but not in POAG or NTG eyes. There were no significant differences in oxygen saturation in venules or arteriovenous (AV difference in all three glaucoma groups. Venular diameter was significantly reduced in all glaucoma groups compared to normal controls (P<0.001, but no such change was observed in arteriolar diameter (P=0.10. When comparing between eyes of asymmetrical glaucoma severity, arteriolar oxygen saturation (P=0.03 and AV difference (P=0.04 were significantly higher, while arteriolar diameter was significantly lower (P=0.001 in the worse eye in PACG group. There were no significant

Laser-induced cracks in ice due to temperature gradient and thermal stress

Science.gov (United States)

Yang, Song; Yang, Ying-Ying; Zhang, Jing-Yuan; Zhang, Zhi-Yan; Zhang, Ling; Lin, Xue-Chun

2018-06-01

This work presents the experimental and theoretical investigations on the mechanism of laser-induce cracks in ice. The laser-induced thermal gradient would generate significant thermal stress and lead to the cracking without thermal melting in the ice. The crack density induced by a pulsed laser in the ice critically depends on the laser scanning speed and the size of the laser spot on the surface, which determines the laser power density on the surface. A maximum of 16 cracks within an area of 17 cm × 10 cm can be generated when the laser scanning speed is at 10 mm/s and the focal point of the laser is right on the surface of the ice with a laser intensity of ∼4.6 × 107 W/cm2. By comparing the infrared images of the ice generated at various experimental conditions, it was found that a larger temperature gradient would result in more laser-induced cracks, while there is no visible melting of the ice by the laser beam. The data confirm that the laser-induced thermal stress is the main cause of the cracks created in the ice.

Determinants of glaucoma awareness in urban punjab

International Nuclear Information System (INIS)

Farooq, S.; Jaffar, S.; Kausar, A.

2015-01-01

To assess the awareness about glaucoma and the factors affecting it in urban Punjab population. Study Design: Cross-sectional study. Place and Duration of Study: Study was conducted in March-April 2011 in Rawalpindi District Punjab, Pakistan. Material and Methods: Glaucoma awareness study was conducted on urban population of Rawalpindi, Islamabad, Lahore and Taxila. Individuals belonging to medical profession (doctors, nurses and paramedics etc) were not included. Demographic details and educational status of all participants were documented. A brief structured close-ended study questionnaire was used to collect information about their awareness of risk factors, treatment aspects and complication of glaucoma. Results: There were 729 participants in the study. Majority were females (60.1%) and adults (76.1%). Literacy level of 40.2% was up to matriculate level. The study indicated that the awareness level about glaucoma was low especially about the recognition of high-risk groups and symptoms. Only one-third of respondents i.e. 32.6% had an idea about the symptoms of the disease and 27.4% participants had awareness of glaucoma as a blinding eye disease. Determinants of glaucoma awareness amongst study participants were gender, age, education level and occupation. Conclusion: Awareness of glaucoma was quite low among the urban population in Punjab. There is need of increased public health education to reduce glaucoma associated blindness and its burden on society. (author)

Clinical utility of anterior segment swept-source optical coherence tomography in glaucoma

Directory of Open Access Journals (Sweden)

Dewang Angmo

2016-01-01

Full Text Available Optical coherence tomography (OCT, a noninvasive imaging modality that uses low-coherence light to obtain a high-resolution cross-section of biological structures, has evolved dramatically over the years. The Swept-source OCT (SS-OCT makes use of a single detector with a rapidly tunable laser as a light source. The Casia SS-1000 OCT is a Fourier-domain, SS-OCT designed specifically for imaging the anterior segment. This system achieves high resolution imaging of 10΅m (Axial and 30΅m (Transverse and high speed scanning of 30,000 A-scans per second. With a substantial improvement in scan speed, the anterior chamber angles can be imaged 360 degrees in 128 cross sections (each with 512 A-scans in about 2.4 seconds. We summarize the clinical applications of anterior segment SS-OCT in Glaucoma. Literature search: We searched PubMed and included Medline using the phrases anterior segment optical coherence tomography in ophthalmology, swept-source OCT, use of AS-OCT in glaucoma, use of swept-source AS-OCT in glaucoma, quantitative assessment of angle, filtering bleb in AS-OCT, comparison of AS-OCT with gonioscopy and comparison of AS-OCT with UBM. Search was made for articles dating 1990 to August 2015.

Evaluation of a glaucoma patient

Science.gov (United States)

Thomas, Ravi; Loibl, Klaus; Parikh, Rajul

2011-01-01

The diagnosis of glaucoma is usually made clinically and requires a comprehensive eye examination, including slit lamp, applanation tonometry, gonioscopy and dilated stereoscopic evaluation of the optic disc and retina. Automated perimetry is obtained if glaucoma is suspected. This establishes the presence of functional damage and provides a baseline for follow-up. Imaging techniques are not essential for the diagnosis but may have a role to play in the follow-up. We recommend a comprehensive eye examination for every clinic patient with the objective of detecting all potentially sight-threatening diseases, including glaucoma. PMID:21150033

Management of Blood Pressure in Patients with Glaucoma.

Science.gov (United States)

Levine, Russell M; Yang, Alina; Brahma, Venkatesh; Martone, James F

2017-09-19

Ocular perfusion pressure (OPP) is defined as the difference between BP and intraocular pressure (IOP). With low BP comes low OPP and resultant ischemic damage to the optic nerve, leading to glaucoma progression. The purpose of this article is to review the literature on BP as it relates to glaucoma and to create a forum of discussion between ophthalmologists and internal medicine specialists. Both high and low BP has been linked glaucoma. Low BP is particularly associated with glaucoma progression in normal-tension glaucoma (NTG) patients. Patients who have low nighttime BP readings are at highest risk of progression of their glaucoma. Internal medicine specialists and ophthalmologists should consider the relationship between BP and glaucoma when treating patients with concomitant disease. Too-low nighttime BP should be avoided. Ambulatory blood pressure monitoring is a useful tool to identify patients at greatest risk for progression.

Ahmed glaucoma valve implant: surgical technique and complications

Directory of Open Access Journals (Sweden)

Riva I

2017-02-01

Full Text Available Ivano Riva,1 Gloria Roberti,1 Francesco Oddone,1 Anastasios GP Konstas,2 Luciano Quaranta3 1IRCCS “Fondazione GB Bietti per l’Oftalmologia”, Rome, Italy; 21st University Department of Ophthalmology, Glaucoma Unit, AHEPA Hospital, Thessaloniki, Greece; 3Department of Medical and Surgical Specialties, Section of Ophthalmology, University of Brescia, Brescia, Italy Abstract: Implantation of Ahmed glaucoma valve is an effective surgical technique to reduce intraocular pressure in patients affected with glaucoma. While in the past, the use of this device was reserved to glaucoma refractory to multiple filtration surgical procedures, up-to-date mounting experience has encouraged its use also as a primary surgery for selected cases. Implantation of Ahmed glaucoma valve can be challenging for the surgeon, especially in patients who already underwent previous multiple surgeries. Several tips have to be acquired by the surgeon, and a long learning curve is always needed. Although the valve mechanism embedded in the Ahmed glaucoma valve decreases the risk of postoperative hypotony-related complications, it does not avoid the need of a careful follow-up. Complications related to this type of surgery include early and late postoperative hypotony, excessive capsule fibrosis around the plate, erosion of the tube or plate edge, and very rarely infection. The aim of this review is to describe surgical technique for Ahmed glaucoma valve implantation and to report related complications. Keywords: glaucoma, surgical technique, glaucoma drainage devices, Ahmed glaucoma valve, complications

Goniodysgenesis in familial primary open-angle glaucoma

NARCIS (Netherlands)

Verbraak, F. D.; vd Berg, W.; Delleman, J. W.; Greve, E. L.

1994-01-01

Results of a pilot study to evaluate goniodysgenesis as a cause of familial open-angle glaucoma are reported. Patients with a familial high tension open-angle glaucoma and a goniodysgenetic chamber angle (n = 11), a number of their relatives with glaucoma (n = 12), and their relatives without

Heparanase-1 activities in the development of laser induced choroidal neovascularization

Directory of Open Access Journals (Sweden)

Bao-Ke Hou

2013-04-01

Full Text Available AIM:To investigate the role of heparanase-1 in laser-induced choroidal neovascularization (CNV.METHODS:Experimental CNV was induced by krypton laser photocoagulation in 15 male Brown Norway rats. Fundus fluorescein angiography and histopathological examination were performed in observing the CNV development. The expression and distribution of heparanase-1 protein in the laser lesions were determined by immunohistochemistry and western blotting analysis.RESULTS:The success rate of laser induced CNV was approximately 75% on 3-4 weeks after laser photocoagulation. The protein levels of heparanase-1 increased significantly in the retina-choroidal complex of CNV models when compared to normal rat eyes (P<0.01. Immunostaining confirmed strong heparanase-1 expressions in all laser lesions, and it displayed to be highest at the newly formed blood vessels within the fibrovascular complex in the subretinal space.CONCLUSION:Heparanase-1 is closely involved in the development of laser induced CNV.

The Advanced Glaucoma Intervention Study (AGIS): 5. Encapsulated bleb after initial trabeculectomy.

Science.gov (United States)

Schwartz, A L; Van Veldhuisen, P C; Gaasterland, D E; Ederer, F; Sullivan, E K; Cyrlin, M N

1999-01-01

To compare the incidence of encapsulated bleb after trabeculectomy in eyes with and without previous argon laser trabeculoplasty and to assess other risk factors for encapsulated bleb development. After medical treatment failure, eyes enrolled in the Advanced Glaucoma Intervention Study (AGIS) were randomly assigned to sequences of interventions starting with either argon laser trabeculoplasty or trabeculectomy. In the present study we compared the clinical course for 1 year after trabeculectomy in 119 eyes with failed argon laser trabeculoplasty with that of 379 eyes without previous argon laser trabeculoplasty. Data on bleb encapsulation were collected at the time that the encapsulation was diagnosed, and 3 and 6 months later. Of multiple factors examined in the AGIS data for the risk of developing encapsulated bleb, only male gender and high school graduation without further formal education were statistically significant. Encapsulation occurred in 18.5% of eyes with previous argon laser trabeculoplasty failure and 14.5% of eyes without previous argon laser trabeculoplasty (unadjusted relative risk, 1.27; 95% confidence limits = 0.81, 2.00; P = .23). After adjusting for age, gender, educational achievement, prescribed systemic beta-blockers, diabetes, visual field score, and years since glaucoma diagnosis, this difference remains statistically not significant. Four weeks after trabeculectomy, mean intraocular pressure was 7.5 mm Hg higher in eyes with (22.5 mm Hg) than without (15.0 mm Hg) encapsulated bleb; at 1 year after trabeculectomy and the resumption of medical therapy when needed, this excess was reduced to 1.4 mm Hg. This study, as did two previous studies, found male gender to be a risk factor for bleb encapsulation. Four studies, including the present study, have reported a higher rate of encapsulation in eyes with previous argon laser trabeculoplasty; in two of the studies, one of which was the present study, the rate was not statistically

Glaucoma

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Watch Out for Glaucoma | NIH MedlinePlus the Magazine

Science.gov (United States)

... of this page please turn JavaScript on. Feature: Glaucoma Watch Out for Glaucoma Past Issues / Spring 2015 Table of Contents A ... used to check eye pressure for signs of glaucoma. Photo courtesy of NEI Glaucoma is a group ...

Minimally invasive non-thermal laser technology using laser-induced optical breakdown for skin rejuvenation

NARCIS (Netherlands)

Habbema, L.; Verhagen, R.; Van Hal, R.; Liu, Y.; Varghese, B.

2011-01-01

We describe a novel, minimally invasive laser technology for skin rejuvenation by creating isolated microscopic lesions within tissue below the epidermis using laser induced optical breakdown. Using an in-house built prototype device, tightly focused near-infrared laser pulses are used to create

Optimization of an Image-Guided Laser-Induced Choroidal Neovascularization Model in Mice.

Directory of Open Access Journals (Sweden)

Yan Gong

Full Text Available The mouse model of laser-induced choroidal neovascularization (CNV has been used in studies of the exudative form of age-related macular degeneration using both the conventional slit lamp and a new image-guided laser system. A standardized protocol is needed for consistent results using this model, which has been lacking. We optimized details of laser-induced CNV using the image-guided laser photocoagulation system. Four lesions with similar size were consistently applied per eye at approximately double the disc diameter away from the optic nerve, using different laser power levels, and mice of various ages and genders. After 7 days, the mice were sacrificed and retinal pigment epithelium/choroid/sclera was flat-mounted, stained with Isolectin B4, and imaged. Quantification of the area of the laser-induced lesions was performed using an established and constant threshold. Exclusion criteria are described that were necessary for reliable data analysis of the laser-induced CNV lesions. The CNV lesion area was proportional to the laser power levels. Mice at 12-16 weeks of age developed more severe CNV than those at 6-8 weeks of age, and the gender difference was only significant in mice at 12-16 weeks of age, but not in those at 6-8 weeks of age. Dietary intake of omega-3 long-chain polyunsaturated fatty acid reduced laser-induced CNV in mice. Taken together, laser-induced CNV lesions can be easily and consistently applied using the image-guided laser platform. Mice at 6-8 weeks of age are ideal for the laser-induced CNV model.

Service innovation in glaucoma management: using a Web-based electronic patient record to facilitate virtual specialist supervision of a shared care glaucoma programme.

Science.gov (United States)

Wright, Heathcote R; Diamond, Jeremy P

2015-03-01

To assess the importance of specialist supervision in a new model of glaucoma service delivery. An optometrist supported by three technicians managed each glaucoma clinic. Patients underwent testing and clinical examination before the optometrist triaged them into one of five groups: 'normal', 'stable', 'low risk', 'unstable' and 'high risk'. Patient data were uploaded to an electronic medical record to facilitate virtual review by a glaucoma specialist. 24 257 glaucoma reviews at three glaucoma clinics during a 31-month period were analysed. The clinic optometrists and glaucoma specialists had substantial agreement (κ 0.69). 13 patients were identified to be high risk by the glaucoma specialist that had not been identified as such by the optometrist. Glaucoma specialists amended 13% of the optometrists' interim decisions resulting in an overall reduction in review appointments by 2.4%. Employing technicians and optometrists to triage glaucoma patients into groups defined by risk of blindness allows higher risk patients to be directed to a glaucoma specialist. Virtual review allows the glaucoma specialist to remain in overall control while reducing the risk that patients are treated or followed-up unnecessarily. Demand for glaucoma appointments can be reduced allowing scarce medical resources to be directed to patients most in need. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Ability of spectral domain optical coherence tomography peripapillary retinal nerve fiber layer thickness measurements to identify early glaucoma

Directory of Open Access Journals (Sweden)

Tarannum Mansoori

2011-01-01

Full Text Available Purpose : To evaluate the ability of spectral domain optical coherence tomography (OCT peripapillary retinal nerve fiber layer thickness (RNFLT parameters to distinguish normal eyes from those with early glaucoma in Asian Indian eyes. Design : Observational cross-sectional study. Materials and Methods : One hundred and seventy eight eyes (83 glaucoma patients and 95 age matched healthy subjects of subjects more than 40 years of age were included in the study. All subjects underwent RNFLT measurement with spectral OCT/ scanning laser ophthalmoscope (SLO after dilatation. Sensitivity, specificity and area under the receiving operating characteristic curve (AROC were calculated for various OCT peripapillary RNFL parameters. Results: The mean RNFLT in healthy subjects and patients with early glaucoma were 105.7 ± 5.1 μm and 90.7 ± 7.5 μm, respectively. The largest AROC was found for 12 o′clock- hour (0.98, average (0.96 and superior quadrant RNFLT (0.9. When target specificity was set at ≥ 90% and ≥ 80%, the parameters with highest sensitivity were 12 o′clock -hour (91.6%, average RNFLT (85.3% and 12 o′ clock- hour (96.8 %, average RNFLT (94.7% respectively. Conclusion : Our study showed good ability of spectral OCT/ SLO to differentiate normal eyes from patients with early glaucoma and hence it may serve as an useful adjunct for early diagnosis of glaucoma.

Glaucoma

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Surface modifications induced by pulsed-laser texturing—Influence of laser impact on the surface properties

Energy Technology Data Exchange (ETDEWEB)

Costil, S., E-mail: sophie.costil@utbm.fr [IRTES-LERMPS, Université de Technologie de Belfort - Montbéliard, site de Sévenans, 90010 Belfort Cedex (France); Lamraoui, A.; Langlade, C. [IRTES-LERMPS, Université de Technologie de Belfort - Montbéliard, site de Sévenans, 90010 Belfort Cedex (France); Heintz, O.; Oltra, R. [ICB, Université de Bourgogne, 21078 Dijon Cedex (France)

2014-01-01

Laser cleaning technology provides a safe, environmentally friendly and very cost effective way to improve cleaning and surface preparation of metallic materials. Compared with efficient cleaning processes, it can avoid the disadvantages of ductile materials prepared by conventional technologies (cracks induced by sand-blasting for example) and treat only some selected areas (due to the optical fibers). By this way, laser technology could have several advantages and expand the range of thermal spraying. Moreover, new generations of lasers (fiber laser, disc laser) allow the development of new methods. Besides a significant bulk reduction, no maintenance, low operating cost, laser fibers can introduce alternative treatments. Combining a short-pulse laser with a scanner allows new applications in terms of surface preparation. By multiplying impacts using scanning laser, it is possible to shape the substrate surface to improve the coating adhesion as well as the mechanical behaviour. In addition, during the interactions of the laser beam with metallic surfaces, several modifications can be induced and particularly thermal effects. Indeed, under ambient conditions, a limited oxidation of the clean surface can occur. This phenomenon has been investigated in detail for silicon but few works have been reported concerning metallic materials. This paper aims at studying the surface modifications induced on aluminium alloy substrates after laser texturing. After morphological observations (SEM), a deeper surface analysis will be performed using XPS (X-ray photoelectron spectroscopy) measures and microhardness testing.

Potential applications of optical coherence tomography angiography in glaucoma.

Science.gov (United States)

Dastiridou, Anna; Chopra, Vikas

2018-05-01

Optical coherence tomography angiography (OCTA) is a novel, noninvasive imaging modality that allows assessment of the retinal and choroidal vasculature. The scope of this review is to summarize recent studies using OCTA in glaucoma and highlight potential applications of this new technology in the field of glaucoma. OCTA studies have shown that retinal vascular changes may not develop solely as a result of advanced glaucoma damage. OCTA-derived measurements have provided evidence for lower retinal vascular densities at the optic nerve head, peripapillary and macula in preperimetric-glaucoma and early-glaucoma, as well as, in more advanced glaucoma, in comparison to with normal eyes. OCTA is a novel imaging modality that has already started to expand our knowledge base regarding the role of ocular blood flow in glaucoma. Future studies will better elucidate the role of OCTA-derived measurements in clinical practice, research, and clinical trials in glaucoma.

Remote imaging laser-induced breakdown spectroscopy and laser-induced fluorescence spectroscopy using nanosecond pulses from a mobile lidar system.

Science.gov (United States)

Grönlund, Rasmus; Lundqvist, Mats; Svanberg, Sune

2006-08-01

A mobile lidar system was used in remote imaging laser-induced breakdown spectroscopy (LIBS) and laser-induced fluorescence (LIF) experiments. Also, computer-controlled remote ablation of a chosen area was demonstrated, relevant to cleaning of cultural heritage items. Nanosecond frequency-tripled Nd:YAG laser pulses at 355 nm were employed in experiments with a stand-off distance of 60 meters using pulse energies of up to 170 mJ. By coaxial transmission and common folding of the transmission and reception optical paths using a large computer-controlled mirror, full elemental imaging capability was achieved on composite targets. Different spectral identification algorithms were compared in producing thematic data based on plasma or fluorescence light.

Palladium-103 plaque radiation therapy for ciliary body melanoma through a functioning glaucoma filtering bleb.

Science.gov (United States)

Pathan, Arif H K; Barash, Alexander; Tena, Lawrence B; Finger, Paul T

2018-01-01

To provide a clinical description of the long-term outcome of a 103 Pd plaque-irradiated ciliary body melanoma with extrascleral extension while attempting to preserve a subadjacent glaucoma filtering bleb. A 75-year-old woman with pseudoexfoliative glaucoma for 17 years, 16 years status post argon laser trabeculoplasty, and 15 years status post trabeculectomy in the left eye, was diagnosed with an ipsilateral ciliary body melanoma with visible extrascleral extension. Treatment involved insertion of a 103 Pd radioactive plaque over the functioning trabeculectomy, with removal 7 days later. At plaque insertion, amniotic membrane grafts were used to cover the plaque and protect the filtering site. The tumor was successfully treated without clinical evidence of harm to the filtering bleb, with resultant stable intraocular pressure. However, the patient developed blebitis 1.5 years later. Though it resolved with topical antibiotic therapy, the bleb became less succulent. Two years postoperatively, she developed a spontaneous hyphema that resolved after one injection of transscleral bevacizumab 1.25 mg. Her tumor continually regressed in thickness. Without additional glaucoma surgery, her intraocular pressure remained well-controlled on topical medications for 6 years. Ciliary body melanoma with minimal extrascleral extension beneath a functioning filtering bleb can be treated using radioactive plaque therapy. In this case, we were able to achieve both tumor regression and glaucoma control by covering the plaque with an amniotic membrane graft.

Glaucoma

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Iridotomy with red krypton laser.

Science.gov (United States)

Yassur, Y; David, R; Rosenblatt, I; Marmour, U

1986-01-01

Iridotomy with red krypton laser instead of blue-green argon laser was performed on 68 eyes with various types of angle-closure glaucoma. Patent iridotomy was obtained in all the eyes, mostly in one working session. In eight eyes secondary closure by pigment needed reopening with a few applications at the iridotomy site. There were no immediate or late complications of importance, the main advantage of the technique being the avoidance of the corneal epithelial and endothelial burns which commonly occur during argon laser iridotomy, particularly when the anterior chamber is shallow. PMID:3964628

Glaucoma: Biological Trabecular and Neuroretinal Pathology with Perspectives of Therapy Innovation and Preventive Diagnosis

Directory of Open Access Journals (Sweden)

Raffaele Nuzzi

2017-09-01

Full Text Available Glaucoma is a common degenerative disease affecting retinal ganglion cells (RGC and optic nerve axons, with progressive and chronic course. It is one of the most important reasons of social blindness in industrialized countries. Glaucoma can lead to the development of irreversible visual field loss, if not treated. Diagnosis may be difficult due to lack of symptoms in early stages of disease. In many cases, when patients arrive at clinical evaluation, a severe neuronal damage may have already occurred. In recent years, newer perspective in glaucoma treatment have emerged. The current research is focusing on finding newer drugs and associations or better delivery systems in order to improve the pharmacological treatment and patient compliance. Moreover, the application of various stem cell types with restorative and neuroprotective intent may be found appealing (intravitreal autologous cellular therapy. Advances are made also in terms of parasurgical treatment, characterized by various laser types and techniques. Moreover, recent research has led to the development of central and peripheral retinal rehabilitation (featuring residing cells reactivation and replacement of defective elements, as well as innovations in diagnosis through more specific and refined methods and inexpensive tests.

ASSOCIATION BETWEEN GLAUCOMA AND BLOOD GROUPS

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F. Ghannadi R. Varmazyar

2006-09-01

Full Text Available There are reports from different countries that some types of glaucoma are associated with blood groups. This cross-sectional study was performed on 400 glaucomatous patients [100 patients in each group of Primary open angle glaucoma (POAG, chronic angle closure glaucoma (CACG, pseudoexfoliative glaucoma (PEXG and primary congenital glaucoma (PCG] and 400 blood donors as control group to assess the association between blood groups and glaucoma. All patients underwent ABO and Rh blood group testing. The prevalence of blood group A was 30% in the control group, 27% in POAG, 33% in CACA, 38% in PEXG and 36% in PCG. The prevalence of blood group B was 24% in the control group, 19% in POAG, 20% in CACG, 15% in PEXG and 34% in PCG (P < 0.025. The prevalence of blood group AB was 8% in the control group, 9% in POAG, 5% in CACG, 12% in PEXG, and 8% in PCG. The prevalence of blood group O was 38% in the control group, 45% in POAC, 42% in CACG, 35% in PEXG and 22% in PCG (P < 0.001. The prevalence of Rh+ was 88% in the control group, 84% in POAG, 87% in CACG, 86% in PEXG and 87% in PCG. Compared to control group, blood group B was more prevalent and blood group O was less prevalent in PCG. There was no association between other types of blood groups (ABO and Rh and PCG. There was no association between blood groups (ABO and Rh and other types of glaucoma.

Comparison of axial lengths in occludable angle and angle-closure glaucoma-The Bhaktapur Glaucoma Study

NARCIS (Netherlands)

Thapa, S.S.; Paudyal, I.; Khanal, S.; Paudel, N.; van Rens, G.H.M.B.

2011-01-01

Purpose. To compare the anterior chamber depth (ACD) and axial length of eyes in a population-based sample among normal, occludable angle, and primary angle-closure glaucoma (PACG) groups. Methods. Totally, 3979 subjects from a population-based glaucoma prevalence study underwent complete ocular

Evaluation of a glaucoma patient

Directory of Open Access Journals (Sweden)

Thomas Ravi

2011-12-01

Full Text Available The diagnosis of glaucoma is usually made clinically and requires a comprehensive eye examination, including slit lamp, applanation tonometry, gonioscopy and dilated stereoscopic evaluation of the optic disc and retina. Automated perimetry is obtained if glaucoma is suspected. This establishes the presence of functional damage and provides a baseline for follow-up. Imaging techniques are not essential for the diagnosis but may have a role to play in the follow-up. We recommend a comprehensive eye examination for every clinic patient with the objective of detecting all potentially sight-threatening diseases, including glaucoma.

Profile of glaucoma in a major eye hospital in North India

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Das Jayachandra

2001-01-01

Full Text Available Purpose: To study the clinical profile and distribution of various subtypes of glaucoma in a referral practice in North India. Method: A retrospective analysis was done of 2425 patients who attended the glaucoma clinic in a tertiary eye-care centre for five years from Januaryl995 to December 1999. A detailed history was obtained and a thorough examination was performed, including gonioscopy, disc assessment, applanation tonometry and automated perimetry. Diurnal variation of IOP and provocative tests for glaucoma were done where applicable. Result: Primary angle closure glaucoma (PACG was the most common glaucoma subtype. The primary open angle glaucoma (POAG to the PACG ratio was 37:63. Chronic angle closure glaucoma (CACG was the most common PACG subtype. The majority of CACG cases were relatively asymptomatic. Male dominance was seen for POAG, juvenile open angle glaucoma (JOAG, CACG, normal tension glaucoma (NTG and secondary glaucomas. Female dominance was seen for ocular hypertension (OHT, acute or intermittent ACG and developmental glaucomas. The mean age in years at presentation was POAG: 60.54 years (males 61.54 years, females 59.01 years and PACG: 55.13 years (males 57.25 years, females 53.60. The three common secondary glaucomas were: glaucoma secondary to adherent leucoma, aphakic and pseudophakic glaucomas and traumatic glaucomas. Advanced glaucoma was detected in 42 to 53% of patients and bilateral blindness in 8 to 14% of patients in various subtypes. Conclusion: Compared to Caucasians, glaucoma patients in North India seem to present nearly a decade earlier and the disease is more advanced at presentation. While PACG is the most commonly encountered glaucoma, NTG and exfoliative glaucoma are relatively rare.

Glaucoma

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Glaucoma

Science.gov (United States)

... considerably, providing more precise visual assessment tests and biologic markers for the disease. NIH-sponsored research led to the development of prostaglandins, a new class of drugs that offers excellent IOP control with fewer side effects. The Early Manifest Glaucoma ...

Association between optic nerve blood flow and objective examinations in glaucoma patients with generalized enlargement disc type

Directory of Open Access Journals (Sweden)

Nakazawa T

2011-10-01

Full Text Available Naoki Chiba, Kazuko Omodaka, Yu Yokoyama, Naoko Aizawa, Satoru Tsuda, Masayuki Yasuda, Takaaki Otomo, Shunji Yokokura, Nobuo Fuse, Toru Nakazawa Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan Background: The purpose of this study was to investigate the correlations between microcirculation in the optic disc, average peripapillary retinal nerve fiber layer thickness cupping parameters, and visual field defects in glaucoma patients with the generalized enlargement disc type. Methods: A total of 38 eyes from 38 glaucoma patients with the generalized enlargement disc type were included. The microcirculation of the optic nerve head was examined with laser speckle flow graphy, and the mean blur rate in all areas, in vessel area, and in tissue area were calculated using the laser speckle flow graphy analyzer software. Average peripapillary retinal nerve fiber layer thickness was measured using Stratus optical coherence tomography, and cupping parameters were accessed using the Heidelberg retina tomograph. The mean deviation in the Humphrey field analyzer (30-2 SITA standard was analyzed. The correlation between these parameters was evaluated using the Spearman rank correlation coefficient. Results: The correlation coefficient of mean blur rate in all optic disc area to the average peripapillary retinal nerve fiber layer thickness, vertical C/D, and mean deviation were r = 0.7546 (P < 0.0001, r = –0.6208 (P < 0.0001, and r = 0.6010 (P = 0.0001, respectively. The mean blur rate in tissue area of the optic disc showed r = 0.7305 (P < 0.0001, r = –0.6438 (P < 0.0001, and r = 0.6338 (P < 0.0001. Conclusion: We found that the mean blur rate in the optic disc was significantly correlated with the average peripapillary retinal nerve fiber layer thickness, vertical C/D, and mean deviation in patients with the generalized enlargement disc type of glaucoma. In particular, the mean blur rate in tissue area was more

Level of agreement among Latin American glaucoma subspecialists on the diagnosis and treatment of glaucoma: results of an online survey

OpenAIRE

Daniel E. Grigera; Paulo Augusto Arruda Mello; Wilma Lelis Barbosa; Javier Fernando Casiraghi; Rodolfo Perez Grossmann; Alejo Peyret

2013-01-01

PURPOSE: The aim of this research was to assess the level of agreement among glaucoma experts in Latin America on key practices related to treatment and diagnosis of glaucoma. METHODS: An online questionnaire was sent to a multinational panel of glaucoma experts. The questionnaire contained 107 statements on the medical treatment (Part 1) and diagnosis (Part 2) of glaucoma, and was developed in Spanish and translated into English. Agreement was defined as >70% of respondents. RESULTS: Fifty p...

Robust optimization of the laser induced damage threshold of dielectric mirrors for high power lasers.

Science.gov (United States)

Chorel, Marine; Lanternier, Thomas; Lavastre, Éric; Bonod, Nicolas; Bousquet, Bruno; Néauport, Jérôme

2018-04-30

We report on a numerical optimization of the laser induced damage threshold of multi-dielectric high reflection mirrors in the sub-picosecond regime. We highlight the interplay between the electric field distribution, refractive index and intrinsic laser induced damage threshold of the materials on the overall laser induced damage threshold (LIDT) of the multilayer. We describe an optimization method of the multilayer that minimizes the field enhancement in high refractive index materials while preserving a near perfect reflectivity. This method yields a significant improvement of the damage resistance since a maximum increase of 40% can be achieved on the overall LIDT of the multilayer.

Ocular hemodynamics and glaucoma: the role of mathematical modeling.

Science.gov (United States)

Harris, Alon; Guidoboni, Giovanna; Arciero, Julia C; Amireskandari, Annahita; Tobe, Leslie A; Siesky, Brent A

2013-01-01

To discuss the role of mathematical modeling in studying ocular hemodynamics, with a focus on glaucoma. We reviewed recent literature on glaucoma, ocular blood flow, autoregulation, the optic nerve head, and the use of mathematical modeling in ocular circulation. Many studies suggest that alterations in ocular hemodynamics play a significant role in the development, progression, and incidence of glaucoma. Although there is currently a limited number of studies involving mathematical modeling of ocular blood flow, regulation, and diseases (such as glaucoma), preliminary modeling work shows the potential of mathematical models to elucidate the mechanisms that contribute most significantly to glaucoma progression. Mathematical modeling is a useful tool when used synergistically with clinical and laboratory data in the study of ocular blood flow and glaucoma. The development of models to investigate the relationship between ocular hemodynamic alterations and glaucoma progression will provide a unique and useful method for studying the pathophysiology of glaucoma.

Prevalence of glaucoma in a Nigerian hospital | Usifoh | Journal of ...

African Journals Online (AJOL)

Primary Open Angle Glaucoma (POAG) was the most common type of glaucoma (91.24%), followed by Normal Tension Glaucoma (NTG) with a prevalence of 3.23%. No significant association was found between age or sex and types of glaucoma. PACG and Juvenile glaucoma remains relatively rare accounting for only ...

Ultrafast molecular imaging by laser-induced electron diffraction

International Nuclear Information System (INIS)

Peters, M.; Nguyen-Dang, T. T.; Cornaggia, C.; Saugout, S.; Charron, E.; Keller, A.; Atabek, O.

2011-01-01

We address the feasibility of imaging geometric and orbital structures of a polyatomic molecule on an attosecond time scale using the laser-induced electron diffraction (LIED) technique. We present numerical results for the highest molecular orbitals of the CO 2 molecule excited by a near-infrared few-cycle laser pulse. The molecular geometry (bond lengths) is determined within 3% of accuracy from a diffraction pattern which also reflects the nodal properties of the initial molecular orbital. Robustness of the structure determination is discussed with respect to vibrational and rotational motions with a complete interpretation of the laser-induced mechanisms.

Long-term Outcomes of Ahmed Glaucoma Valve Implantation in Refractory Glaucoma at Farabi Eye Hospital, Tehran, Iran.

Science.gov (United States)

Zarei, Reza; Amini, Heidar; Daneshvar, Ramin; Nabi, Fahimeh Naderi; Moghimi, Sasan; Fakhraee, Ghasem; Eslami, Yadollah; Mohammadi, Masoud; Amini, Nima

2016-01-01

To describe long-term outcomes and complications of Ahmed glaucoma valve (AGV) implantation in subjects with refractory glaucoma at Farabi Eye Hospital, Tehran, Iran. This retrospective cohort study evaluated patient records of all subjects with refractory glaucoma who had undergone AGV implantation up to January 2013. The main outcome measure was the surgical success rate. Complete success was defined as intraocular pressure (IOP) glaucoma medications or additional surgery. Qualified success was IOP glaucoma medications. In all cases, loss of vision (no light perception) was considered an independent indicator of failure. Data were also collected on intraoperative and postoperative complications. Twenty-eight eyes were included in the study. With a mean follow-up of 48.2 ± 31.7 months (median: 40.50 months; range: 3-124 months), the IOP decreased from a mean preoperative value of 30.8 ± 5.6 mmHg to 20.0 ± 6.4 mmHg at last visit. The number of medications decreased from 3.7 ± 0.4 preoperatively to 2.5 ± 1.1 postoperatively. Cumulative qualified success was achieved in 69% of eyes. Mean time to failure according to qualified success criteria was 92.3 ± 9.4 months. Postoperative complications were recorded in 16 (57.1%) eyes. The most common complication was focal endothelial corneal decompensation at the site of tube-cornea touch. AGV implantation with adjunctive topical anti-glaucoma drops controlled IOP in approximately 70% of eyes with refractory glaucoma with a median of 40.5 months of follow-up. However, complication rates were higher.

Laser-induced shockwave propagation from ablation in a cavity

International Nuclear Information System (INIS)

Zeng Xianzhong; Mao Xianglei; Mao, Samuel S.; Wen, S.-B.; Greif, Ralph; Russo, Richard E.

2006-01-01

The propagation of laser-induced shockwaves from ablation inside of cavities was determined from time-resolved shadowgraph images. The temperature and electron number density of the laser-induced plasma was determined from spectroscopic measurements. These properties were compared to those for laser ablation on the flat surface under the same energy and background gas condition. A theoretical model was proposed to determine the amount of energy and vaporized mass stored in the vapor plume based on these measurements

Aqueous shunt implantation in glaucoma

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Jing Wang

2017-01-01

Full Text Available Aqueous shunts or glaucoma drainage devices are increasingly utilized in the management of refractory glaucoma. The general design of the most commonly-used shunts is based on the principles of the Molteno implant: ie. a permanent sclerostomy (tube, a predetermined bleb area (plate and diversion of aqueous humour to the equatorial region and away from the limbal subconjunctival space. These three factors make aqueous shunts more resistant to scarring as compared to trabeculectomy. The two most commonly used shunts are the Ahmed Glaucoma Valve, which contains a flow-restrictor, and the non-valved Baervedlt Glaucoma Implant. While the valved implants have a lower tendency to hypotony and related complications, the non-valved implants with larger, more-biocompatible end plate design, achieve lower intraocular pressures with less encapsulation. Non-valved implants require additional suturing techniques to prevent early hypotony and a number of these methods will be described. Although serious shunt-related infection is rare, corneal decompensation and diplopia are small but significant risks.

Ultrasound imaging of Nd:YAG laser-induced tissue coagulation in porcine livers.

Science.gov (United States)

Ritzel, U; Wietzke-Braun, P; Brinck, U; Leonhardt, U; Ramadori, G

2001-12-01

Absorption of laser light energy induces denaturation of proteins and thermocoagulation of irradiated tissue. Recently, MRI-guided laser coagulation in combination with MR thermometry was reported as a treatment of liver tumours. In the present study ultrasonographic imaging was evaluated for its suitability in laser induced tissue thermocoagulation. Fresh porcine livers were used for ex vivo examinations. Placement of the laser catheter and tissue coagulation during laser light emission were online monitored by ultrasonography. Nd:YAG laser-induced tissue damage was evaluated by macroscopical and microscopical examinations of histological sections. During laser light emission a marked hyperdense signal enhancement was observed by ultrasonography which strongly correlated with the extent of macroscopic tissue damage. The size of laser-induced coagulation zone depended on both the power setting and total energy delivered. Carbonization of the tissue surrounding the laser tip is a limiting factor because of laser light absorption. However our data indicate that using appropriate laser energy and exposure time prevent carbonization although carbonization can not be visualized by ultrasonography. It is concluded from the present ex vivo studies that laser coagulation can be effectively performed under ultrasonographic guidance.

The role of inflammation in the pathogenesis of glaucoma

DEFF Research Database (Denmark)

Vohra, Rupali; Tsai, James C; Kolko, Miriam

2013-01-01

Glaucoma is an ocular disorder characterized by the progressive loss of retinal ganglion cells (RGC) and their axons. There are various hypotheses concerning the cause of RGC death. Previously, glaucoma was defined by high intraocular pressure (IOP); during the past decade, however, glaucoma...... specialists have acknowledged that elevated IOP is the most important risk factor for glaucoma, but does not define the disease. Other factors such as genetics, blood flow, and excitotoxicity are suggested as potential causal factors for progressive RGC death observed in glaucoma. We review recent studies...... elucidating a possible role of low-grade inflammation as a causal factor in the pathogenesis of glaucoma....

Childhood glaucoma profile in Dakahelia, Egypt: a retrospective study

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Tharwat H. Mokbel

2018-04-01

Full Text Available AIM: To analyze childhood glaucoma regarding its demographics, presentations, different causes and surgical modalities used among patients in Dakahelia and to apply the Childhood Glaucoma Research Network (CGRN classification retrospectively to evaluate its convenience. METHODS: A retrospective study in which the medical files of all glaucoma patients <16 years old presented to Mansoura Ophthalmic Center, Mansoura University from 2014 to 2017, were retrieved and analyzed. Collected data included: age, gender, laterality, visual acuity (VA, refraction, intraocular pressure (IOP, corneal diameter, cup-disc ratio, types and number of surgeries and antiglaucomatous drugs (AGD at the first and last visit. Prevalence of different subtypes was calculated and means of clinical features were compared. RESULTS: A total of 305 eyes of 207 patients were included classified into 6 groups: primary congenital glaucoma (PCG, juvenile open angle glaucoma (JOAG, glaucoma associated with systemic disease, glaucoma associated with ocular anomalies, acquired glaucoma and glaucoma following cataract surgery. PCG was the predominant type (55.1% followed by acquired glaucoma (29.5%. Males represented 63.8% of the whole studied patients. Glaucoma associated with ocular anomaly group showed the youngest age at diagnosis (21.9±30.0mo. The shortest corneal diameter was recorded in post cataract group (10.4±0.5 mm. Highest cup-disc ratio was found in the PCG group (P<0.0005. Glaucoma associated with systemic disease presented with the highest baseline IOP (34.5±5.0 mm Hg. All the cases with PCG were treated surgically with 21.8% required more than one surgery. The majority of the patients (74.2% in the acquired group were treated medically. Combined trabeculotomy-trabeculectomy was the most frequent operation done, accounting for 34.5% of all primary surgeries. Ahmed valve implantation comprised 87% of the secondary surgeries. Acquired glaucoma group had the highest

Impact of environmental contamination on laser induced damage of silica optics in Laser MegaJoule

International Nuclear Information System (INIS)

Bien-Aime, K.

2009-11-01

Laser induced damage impact of molecular contamination on fused polished silica samples in a context of high power laser fusion facility, such as Laser MegaJoule (LMJ) has been studied. One of the possible causes of laser induced degradation of optical component is the adsorption of molecular or particular contamination on optical surfaces. In the peculiar case of LMJ, laser irradiation conditions are a fluence of 10 J/cm 2 , a wavelength of 351 nm, a pulse duration of 3 ns for a single shot/days frequency. Critical compounds have been identified thanks to environmental measurements, analysis of material outgassing, and identification of surface contamination in the critical environments. Experiments of controlled contamination involving these compounds have been conducted in order to understand and model mechanisms of laser damage. Various hypotheses are proposed to explain the damage mechanism. (author)

Glaucoma

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YBR/EiJ mice: a new model of glaucoma caused by genes on chromosomes 4 and 17

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K. Saidas Nair

2016-08-01

Full Text Available A variety of inherited animal models with different genetic causes and distinct genetic backgrounds are needed to help dissect the complex genetic etiology of glaucoma. The scarcity of such animal models has hampered progress in glaucoma research. Here, we introduce a new inherited glaucoma model: the inbred mouse strain YBR/EiJ (YBR. YBR mice develop a form of pigmentary glaucoma. They exhibit a progressive age-related pigment-dispersing iris disease characterized by iris stromal atrophy. Subsequently, these mice develop elevated intraocular pressure (IOP and glaucoma. Genetic mapping studies utilizing YBR as a glaucoma-susceptible strain and C57BL/6J as a glaucoma-resistant strain were performed to identify genetic loci responsible for the iris disease and high IOP. A recessive locus linked to Tyrp1b on chromosome 4 contributes to iris stromal atrophy and high IOP. However, this is not the only important locus. A recessive locus on YBR chromosome 17 causes high IOP independent of the iris stromal atrophy. In specific eyes with high IOP caused by YBR chromosome 17, the drainage angle (through which ocular fluid leaves the eye is largely open. The YBR alleles of genes on chromosomes 4 and 17 underlie the development of high IOP and glaucoma but do so through independent mechanisms. Together, these two loci act in an additive manner to increase the susceptibility of YBR mice to the development of high IOP. The chromosome 17 locus is important not only because it causes IOP elevation in mice with largely open drainage angles but also because it exacerbates IOP elevation and glaucoma induced by pigment dispersion. Therefore, YBR mice are a valuable resource for studying the genetic etiology of IOP elevation and glaucoma, as well as for testing new treatments.

Digital versus film stereo-photography for assessment of the optic nerve head in glaucoma and glaucoma suspect patients.

Science.gov (United States)

Hasanreisoglu, Murat; Priel, Ethan; Naveh, Lili; Lusky, Moshe; Weinberger, Dov; Benjamini, Yoav; Gaton, Dan D

2013-03-01

One of the leading methods for optic nerve head assessment in glaucoma remains stereoscopic photography. This study compared conventional film and digital stereoscopy in the quantitative and qualitative assessment of the optic nerve head in glaucoma and glaucoma suspect patients. Fifty patients with glaucoma or suspected glaucoma underwent stereoscopic photography of the optic nerve head with a 35-mm color slide film and a digital camera. Photographs/images were presented in random order to 3 glaucoma specialists for independent analysis using a standardized assessment form. Findings for the following parameters were compared among assessors and between techniques: cup/disc (C/D) ratio, state of the optic rim, presence of peripapillary atrophy and appearance of the retinal nerve fiber layer, blood vessels, and lamina cribrosa. The film-based and image-based diagnoses (glaucoma yes/no) were compared as well. Despite high level of agreement across graders using the same method for the horizontal and vertical C/D ratio, (intraclass correlations 0.80 to 0.83), the agreement across graders was much lower for the other parameters using the same method. Similarly the agreement between the findings of the same grader using either method was high for horizontal and vertical C/D ratio, but low for the other parameters. The latter differences were reflected in the disagreement regarding the final diagnosis: The diagnoses differed by technique for each grader in 18% to 46% of eyes, resulting in 38.5% of eyes diagnosed with glaucoma by film photography that "lost" their diagnosis on the digital images, whereas 18.7% of eyes diagnosed as nonglaucomatous by film photography were considered to have glaucoma on the digital images. Although there is consistency between 35-mm film stereoscopy and digital stereoscopy in determining the cup/disc (C/D) ratio, in all other parameters large differences exist, leading to differences in diagnosis. Differences in capturing images between

Trabecular Meshwork Height in Primary Open-Angle Glaucoma Versus Primary Angle-Closure Glaucoma.

Science.gov (United States)

Masis, Marisse; Chen, Rebecca; Porco, Travis; Lin, Shan C

2017-11-01

To determine if trabecular meshwork (TM) height differs between primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG) eyes. Prospective, cross-sectional clinical study. Adult patients were consecutively recruited from glaucoma clinics at the University of California, San Francisco, from January 2012 to July 2015. Images were obtained from spectral-domain optical coherence tomography (Cirrus OCT; Carl Zeiss Meditec, Inc, Dublin, California, USA). Univariate and multivariate linear mixed models comparing TM height and glaucoma type were performed to assess the relationship between TM height and glaucoma subtype. Mixed-effects regression was used to adjust for the use of both eyes in some subjects. The study included 260 eyes from 161 subjects, composed of 61 men and 100 women. Mean age was 70 years (SD 11.77). There were 199 eyes (123 patients) in the POAG group and 61 eyes (38 patients) in the PACG group. Mean TM heights in the POAG and PACG groups were 812 ± 13 μm and 732 ± 27 μm, respectively, and the difference was significant in univariate analysis (P = .004) and in multivariate analysis (β = -88.7 [24.05-153.5]; P = .008). In this clinic-based population, trabecular meshwork height is shorter in PACG patients compared to POAG patients. This finding may provide insight into the pathophysiology of angle closure and provide assistance in future diagnosis, prevention, and management of the angle-closure spectrum of disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

Retinal nerve fiber layer assessment by scanning laser polarimetry and standardized photography

NARCIS (Netherlands)

Niessen, A. G.; van den Berg, T. J.; Langerhorst, C. T.; Greve, E. L.

1996-01-01

To determine whether, in a clinical setting, scanning laser polarimetry and retinal nerve fiber layer photography provide equivalent information on the retinal nerve fiber layer. We prospectively studied 60 patients with glaucoma or ocular hypertension and 24 healthy subjects. With scanning laser

Development and characterization of nano-fiber patch for the treatment of glaucoma.

Science.gov (United States)

Gagandeep; Garg, Tarun; Malik, Basant; Rath, Goutam; Goyal, Amit K

2014-03-12

In the present work polymeric nano-fiber patches was developed for the effective treatment of glaucoma using timolol maleate and dorzolamide hydrochloride as model drugs. The nano-fibers were prepared by electrospinning technique and were characterized on the basis of fiber diameter, morphology, entrapment efficiency, mucoadhesive strength, and drug release behavior, etc. Final formulations were inserted in the cul-de-sac of glaucoma induced rabbits and the efficacy of the formulation was evaluated. The results clearly indicated the potential of the developed formulation for occur drug delivery. There was a significant fall in the intraocular pressure compared to commercial eye drops. Copyright © 2013 Elsevier B.V. All rights reserved.

Bilateral acute angle-closure glaucoma as a first presentation of granulomatosis with polyangiitis (Wegener's

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Alper Mete

Full Text Available ABSTRACT We report a case of bilateral acute angle-closure glaucoma in a patient with undiagnosed granulomatosis with polyangiitis (Wegener's. A 59-year-old man presented with a severe headache, ocular pain, blurred vision, shortness of breath, and mild fever. Clinical examination revealed conjunctival chemosis, corneal edema, and shallow anterior chambers. Closed angles were observed bilaterally on gonioscopy. The patient was treated with intravenous mannitol, oral acetazolamide, and anti-glaucomatous eye drops. Over the following two days, his vision improved and intraocular pressures decreased. Subsequently, laser iridotomies were performed bilaterally and the patient attended consultations with our departments of respiratory medicine, nephrology, and rheumatology and was subsequently diagnosed with granulomatosis with polyangiitis. Bilateral acute angle-closure glaucoma is a very rare ocular manifestation of granulomatosis with polyangiitis. The association of this clinical entity with Wegener's granulomatosis remains unknown.

Electromagnetically induced transparency with broadband laser pulses

International Nuclear Information System (INIS)

Yavuz, D. D.

2007-01-01

We suggest a scheme to slow and stop broadband laser pulses inside an atomic medium using electromagnetically induced transparency. Extending the suggestion of Harris et al. [Phys. Rev. Lett. 70, 552 (1993)], the key idea is to use matched Fourier components for the probe and coupling laser beams

Change in Visual Field Progression Following Treatment Escalation in Primary Open-angle Glaucoma.

Science.gov (United States)

Aptel, Florent; Bron, Alain M; Lachkar, Yves; Schweitzer, Cédric

2017-10-01

To evaluate the effect of treatment escalation on the rate of visual field progression in patients with primary open-angle glaucoma (POAG). Multicenter database study. We reviewed the electronic records of 171 patients with POAG under medical hypotensive treatment who underwent 5 consecutive visits 6 months apart before and after medical treatment escalation or additive laser trabeculoplasty. We calculated the rate of visual field progression (mean deviation change per year) before and after treatment escalation. The mean duration of follow-up was 5.1±0.5 years and the mean number of visual field examinations was 10.2±0.2. In 139 eyes with medical treatment escalation, the rate of progression was significantly reduced [from -0.57 to -0.29 dB/y; P=0.022; intraocular pressure (IOP) reduction 11.1%]. In detail, the rate of progression was significantly reduced after escalation from mono to dual therapy, dual to triple therapy, and from mono to triple therapy (-0.35 to -0.24 dB/y, P=0.018; -1.01 to -0.48 dB/y, P=0.038; -1.04 to -0.35 dB/y, P=0.020, respectively). In 32 eyes with additive laser trabeculoplasty, the rate of progression was significantly reduced (-0.60 to -0.24 dB/y; P=0.014; IOP reduction 9.4%). Medical treatment escalation or additive laser trabeculoplasty significantly reduced the rate of visual field progression in POAG. Larger IOP reduction has a greater probability of reducing glaucoma progression.

Glaucoma Blindness at a Tertiary Eye Care Center.

Science.gov (United States)

Stone, Jordan S; Muir, Kelly W; Stinnett, Sandra S; Rosdahl, Jullia A

2015-01-01

Glaucoma is an important cause of irreversible blindness. This study describes the characteristics of a large, diverse group of glaucoma patients and evaluates associations between demographic and clinical characteristics and blindness. Data were gathered via retrospective chart review of patients (N = 1,454) who were seen between July 2007 and July 2010 by glaucoma service providers at Duke Eye Center. Visual acuity and visual field criteria were used to determine whether patients met the criteria for legal blindness. Descriptive and comparative statistical analyses were performed on the glaucoma patients who were not blind (n = 1,258) and those who were blind (n = 196). A subgroup analysis of only those patients with primary open-angle glaucoma was also performed. In this tertiary care population, 13% (n = 196) of glaucoma patients met criteria for legal blindness, nearly one-half of whom (n = 94) were blind from glaucoma, and another one-third of whom (n = 69) had glaucoma-related blindness. The most common glaucoma diagnosis at all levels of vision was primary open-angle glaucoma. A larger proportion of black patients compared with white patients demonstrated vision loss; the odds ratio (OR) for blindness was 2.25 (95% CI, 1.6-3.2) for black patients compared with white patients. The use of systemic antihypertensive medications was higher among patients who were blind compared with patients who were not blind (OR = 2.1; 95% CI, 1.4-3.1). A subgroup analysis including only patients with primary open-angle glaucoma showed similar results for both black race and use of systemic antihypertensive medications. The relationship between use of systemic antihypertensive medications and blindness was not different between black patients and white patients (interaction P = .268). Data were based on chart review, and associations may be confounded by unmeasured factors. Treated systemic hypertension may be correlated with blindness, and the cause cannot be explained solely

Ocular surface disease incidence in patients with open-angle glaucoma

Directory of Open Access Journals (Sweden)

Radenković Marija

2016-01-01

Full Text Available Introduction. Ocular surface disease (OSD is a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbances, tear film instability with potential damage to the ocular surface, accompanied by increased tear film osmolarity and inflammation of the ocular surface. It is a consequence of disrupted homeostasis of lacrimal functional unit. The main pathogenetic mechanism stems from tear hyperosmolarity and tear film instability. The etiological classification is hyposecretory (Sy-Sjögren and non-Sjögren and evaporative (extrinsic and intrinsic form. Delphi panel classification grades disease stages. Antiglaucoma topical therapy causes exacerbation or occurrence of symptoms of dry eye due to main ingredients or preservatives (benzalkonium chloride - BAK, which are dose- and time-dependent. BAK reduces the stability of the lipid layer of tears, the number of goblet cells, induces apoptosis and inflammatory infiltration. Objective. The aim of this study was the analysis of the OSD incidence in open-angle glaucoma patients caused by topical medicamentous therapy. Methods. Retrospective analysis of examined patients with open-angle glaucoma was used. Results. Increased incidence of moderate and advanced OSD Index degrees in the group of primary open-angle glaucoma (POAG and pseudoexfoliative glaucoma. According to the Delphi Panel Scale the most common grade is IIb (POAG and pseudoexfoliative glaucoma. Evaporative form of OSD prevailed in all treatment groups. High percentage of dry eye in patients with higher concentrations of preservatives applied was noticed. Conclusion. OSD should be timely diagnosed and treated. Dry eye has an impact on surgical outcome and postoperative visual acuity, and in order to improve patient compliance and quality of life, symptoms of dry eye should be addressed and medications with lower concentrations of preservatives should be applied.

Ocular surface disease incidence in patients with open-angle glaucoma.

Science.gov (United States)

Radenković, Marija; Stanković-Babić, Gordana; Jovanović, Predrag; Djordjević-Jocić, Jasmina; Trenkić-Božinović, Marija

2016-01-01

Ocular surface disease (OSD) is a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbances, tear film instability with potential damage to the ocular surface, accompanied by increased tear film osmolarity and inflammation of the ocular surface. It is a consequence of disrupted homeostasis of lacrimal functional unit. The main pathogenetic mechanism stems from tear hyperosmolarity and tear film instability. The etiological classification is hyposecretory (Sy-Sjögren and non-Sjögren) and evaporative (extrinsic and intrinsic) form. Delphi panel classification grades disease stages. Antiglaucoma topical therapy causes exacerbation or occurrence of symptoms of dry eye due to main ingredients or preservatives (benzalkonium chloride – BAK), which are dose- and time-dependent. BAK reduces the stability of the lipid layer of tears, the number of goblet cells, induces apoptosis and inflammatory infiltration. The aim of this study was the analysis of the OSD incidence in open-angle glaucoma patients caused by topical medicamentous therapy. Retrospective analysis of examined patients with open-angle glaucoma was used. Increased incidence of moderate and advanced OSD Index degrees in the group of primary open-angle glaucoma (POAG) and pseudoexfoliative glaucoma. According to the Delphi Panel Scale the most common grade is IIb (POAG and pseudoexfoliative glaucoma). Evaporative form of OSD prevailed in all treatment groups. High percentage of dry eye in patients with higher concentrations of preservatives applied was noticed. OSD should be timely diagnosed and treated. Dry eye has an impact on surgical outcome and postoperative visual acuity, and in order to improve patient compliance and quality of life, symptoms of dry eye should be addressed and medications with lower concentrations of preservatives should be applied.

The Ex-PRESS glaucoma shunt versus trabeculectomy in open-angle glaucoma: a prospective randomized study

NARCIS (Netherlands)

de Jong, Leo A. M. S.

2009-01-01

The purpose of this study was to establish the efficacy and safety of the Ex-PRESS (Optonol Ltd., Neve Ilan, Israel) mini glaucoma shunt in open-angle glaucoma. This was a prospective, randomized trial. Eyes from enrolled patients were randomly assigned to either Ex-PRESS implantation under a

Glaucoma screening during regular optician visits : can the population at risk of developing glaucoma be reached?

NARCIS (Netherlands)

Stoutenbeek, R.; Jansonius, N. M.

2006-01-01

Aim: To determine the percentage of the population at risk of developing glaucoma, which can potentially be reached by conducting glaucoma screening during regular optician visits. Methods: 1200 inhabitants aged > 40 years were randomly selected from Dutch community population databases. A

The interrelation between hypothyroidism and glaucoma

DEFF Research Database (Denmark)

Thvilum, Marianne; Hjelm Brandt Kristensen, Frans; Brix, Thomas Heiberg

2017-01-01

Data on the association between hypothyroidism and glaucoma are conflicting. We sought to shed light on this by conducting a critical review and meta-analyses. The meta-analyses were conducted in adherence with the widely accepted MOOSE guidelines. Using the Medical Subject Heading (MeSH) terms......: hypothyroidism, myxoedema and glaucoma or intraocular pressure, case-control studies, cohort studies and cross-sectional studies were identified (PubMed) and reviewed. Using meta-analysis, the relative risk (RR) of coexistence of glaucoma and hypothyroidism was calculated. Based on the literature search......, thirteen studies fulfilled the inclusion criteria and could be categorized into two groups based on the exposure. The designs of the studies varied considerably, and there was heterogeneity related to lack of power, weak phenotype classifications and length of follow-up. Eight studies had glaucoma (5757...

Laser induced fusion - theoretical aspects

International Nuclear Information System (INIS)

Lawande, S.V.; Gunye, M.R.

1979-01-01

The theoretical aspects of thermonuclear fusion induced by laser are discussed. After outlining the basic features and the energetics of laser fusion in the chapter 1, various non-linear mechanisms responsible for an enhanced absorption of laser energy into the plasma and the stimulated scattering processes which hinder the absorption are discussed in the second chapter on laser plasma interactions. The third chapter on gas dynamics and the shock phenomena presents the mathematical formulation of the compression to high densities of the core of the pellet for its implosion. A hydrodynamic model developed to stimulate the evolution of laser heated symmetric plasma is outlined in the chapter four on numerichigly relativistic noninteracting particles, regular bouncing states may occur at high densities, or at high temperatures. The latter case is considered in details for the collapse phase of a hot universe; lepton pair creation may completely decelerate the collapse of a hot hadronic plasma, provided the observational parameters, the Hubble constant Hsub(deg), the matter parameter Ωsub(deg) and the deceleration parameter qsub(deg) satisfy certain constraint conditions

The influence of laser-particle interaction in laser induced breakdown spectroscopy and laser ablation inductively coupled plasma spectrometry

International Nuclear Information System (INIS)

Lindner, Helmut; Loper, Kristofer H.; Hahn, David W.; Niemax, Kay

2011-01-01

Particles produced by previous laser shots may have significant influence on the analytical signal in laser-induced breakdown spectroscopy (LIBS) and laser ablation inductively coupled plasma (LA-ICP) spectrometry if they remain close to the position of laser sampling. The effects of these particles on the laser-induced breakdown event are demonstrated in several ways. LIBS-experiments were conducted in an ablation cell at atmospheric conditions in argon or air applying a dual-pulse arrangement with orthogonal pre-pulse, i.e., plasma breakdown in a gas generated by a focussed laser beam parallel and close to the sample surface followed by a delayed crossing laser pulse in orthogonal direction which actually ablates material from the sample and produces the LIBS plasma. The optical emission of the LIBS plasma as well as the absorption of the pre-pulse laser was measured. In the presence of particles in the focus of the pre-pulse laser, the plasma breakdown is affected and more energy of the pre-pulse laser is absorbed than without particles. As a result, the analyte line emission from the LIBS plasma of the second laser is enhanced. It is assumed that the enhancement is not only due to an increase of mass ablated by the second laser but also to better atomization and excitation conditions favored by a reduced gas density in the pre-pulse plasma. Higher laser pulse frequencies increase the probability of particle-laser interaction and, therefore, reduce the shot-to-shot line intensity variation as compared to lower particle loadings in the cell. Additional experiments using an aerosol chamber were performed to further quantify the laser absorption by the plasma in dependence on time both with and without the presence of particles. The overall implication of laser-particle interactions for LIBS and LA-ICP-MS/OES are discussed.

The influence of laser-particle interaction in laser induced breakdown spectroscopy and laser ablation inductively coupled plasma spectrometry

Science.gov (United States)

Lindner, Helmut; Loper, Kristofer H.; Hahn, David W.; Niemax, Kay

2011-02-01

Particles produced by previous laser shots may have significant influence on the analytical signal in laser-induced breakdown spectroscopy (LIBS) and laser ablation inductively coupled plasma (LA-ICP) spectrometry if they remain close to the position of laser sampling. The effects of these particles on the laser-induced breakdown event are demonstrated in several ways. LIBS-experiments were conducted in an ablation cell at atmospheric conditions in argon or air applying a dual-pulse arrangement with orthogonal pre-pulse, i.e., plasma breakdown in a gas generated by a focussed laser beam parallel and close to the sample surface followed by a delayed crossing laser pulse in orthogonal direction which actually ablates material from the sample and produces the LIBS plasma. The optical emission of the LIBS plasma as well as the absorption of the pre-pulse laser was measured. In the presence of particles in the focus of the pre-pulse laser, the plasma breakdown is affected and more energy of the pre-pulse laser is absorbed than without particles. As a result, the analyte line emission from the LIBS plasma of the second laser is enhanced. It is assumed that the enhancement is not only due to an increase of mass ablated by the second laser but also to better atomization and excitation conditions favored by a reduced gas density in the pre-pulse plasma. Higher laser pulse frequencies increase the probability of particle-laser interaction and, therefore, reduce the shot-to-shot line intensity variation as compared to lower particle loadings in the cell. Additional experiments using an aerosol chamber were performed to further quantify the laser absorption by the plasma in dependence on time both with and without the presence of particles. The overall implication of laser-particle interactions for LIBS and LA-ICP-MS/OES are discussed.

Outcomes of Ahmed glaucoma valve implantation in advanced primary congenital glaucoma with previous surgical failure

Directory of Open Access Journals (Sweden)

Huang J

2015-06-01

Full Text Available Jingjing Huang,1 Jialiu Lin,1 Ziqiang Wu,2 Hongzhi Xu,3 Chengguo Zuo,1 Jian Ge1 1State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People’s Republic of China; 2Center for Advanced Eye Care, Carson City, NV, USA; 3Institute of Child Health Policy, University of Florida, Gainesville, FL, USA Purpose: The purpose of this study was to evaluate the intermediate surgical results of Ahmed glaucoma valve (AGV implantation in patients less than 7 years of age, with advanced primary congenital glaucoma who have failed previous surgeries.Patients and methods: Consecutive patients with advanced primary congenital glaucoma that failed previous operations and had undergone subsequent AGV implantation were evaluated retrospectively. Surgical success was defined as 1 intraocular pressure (IOP ≥6 and ≤21 mmHg; 2 IOP reduction of at least 30% relative to preoperative values; and 3 without the need for additional surgical intervention for IOP control, loss of light perception, or serious complications.Results: Fourteen eyes of eleven patients were studied. Preoperatively, the average axial length was 27.71±1.52 (25.56–30.80 mm, corneal diameter was 14.71±1.07 (13.0–16.0 mm, cup-to-disc ratio was 0.95±0.04 (0.9–1.0, and IOP was 39.5±5.7 (30–55 mmHg. The mean follow-up time was 18.29±10.96 (5–44, median 18 months. There were significant reductions in IOPs and the number of glaucoma medications (P<0.001 postoperatively. The IOPs after operation were 11.3±3.4, 13.6±5.1, 16.3±2.7, and 16.1±2.6 mmHg at 1 month, 6 months, 12 months, and 18 months, respectively. Kaplan–Meier estimates of the cumulative probability of valve success were 85.7%, 71.4%, and 71.4% at 6, 12, and 18 months, respectively. Severe surgical complications, including erosion of tube, endophthalmitis, retinal detachment, choroidal detachment, and delayed suprachoroidal hemorrhage, occurred in 28

Importance of intraocular pressure in glaucoma

Science.gov (United States)

Joos, Karen M.

1999-06-01

Glaucoma results in permanent vision loss and affects the peripheral vision initially. It is presented in 22.5 million people worldwide and is the 3rd cause of blindness. Present tonometers are not ideal for intraocular pressure measurements in all eyes. Of concern, PRK and LASIK may result in lower intraocular pressure readings. A challenges now exists for the development of a tonometer which can easily compensate for corneas with many parameters to avoid a future increase in normal-tension glaucoma or glaucoma which is advanced.

Unusual Surprises in Glaucoma Filtering Surgeries: Lessons Learned and Review of Literature.

Science.gov (United States)

Rao, Aparna; Padhy, Debananda; Roy, Avik Kumar; Senthil, Sirisha

2018-01-01

To describe an unusual series of complications after glaucoma filtering surgeries with their clinical findings and outcome after tailored non-conventional modes of therapy. Eighteen patients who underwent re-interventions (medical or surgical) after glaucoma filtering surgeries during the period at two tertiary centers, excluding those that required conventional modes of treatment (medical control or re-trabeculectomy, simple wound closure for traumatic wound dehiscence, bleb revision or needling, laser iridotomy), were included. Relevant clinical details with intraoperative videos, intraoperative or postoperative problems, and images with course after re-intervention were retrieved from the hospital database. Clinical details which helped in clinching diagnosis and cause for problems and course after intervention with final vision and intraocular pressure were evaluated. Six of 18 eyes required surgical management for an unusual course of events after an uneventful filtering surgery. Bleb morphology and close follow-up of the conjunctiva, in addition to intraocular pressure (IOP) and anterior chamber (AC) configuration, helped diagnose possible aetiology and appropriate tailored management. All patients had good IOP and visual outcome in all except one with macular scar status after retinal detachment surgery. Assessment of the bleb morphology in the postoperative course coupled with monitoring of the conjunctival wound are essential to conventional monitoring of IOP and anterior chamber configuration to arrive at appropriate management for rare unusual events after glaucoma surgery.

Visualization of cavitation bubbles induced by a laser pulse

International Nuclear Information System (INIS)

Testud-Giovanneschi, P.; Dufresne, D.; Inglesakis, G.

1987-01-01

The I.M.F.M. researchers working on Laser-Matter Interaction are studying the effects induced on matter by a pulsed radiation energy deposit. In this research, the emphasis is on the laser liquids interaction field and more particularly the cavitation induced by a laser pulse or ''optical-cavitation'' as termed by W. Lauterborn (1). For bubbles investigations, the visualizations form a basic diagnostic. This paper presents the experimental apparatus of formation of bubbles, the visualization apparatus and different typical examples of photographic recordings

Pigment dispersion syndrome and pigmentary glaucoma: a review and update.

Science.gov (United States)

Scuderi, Gianluca; Contestabile, Maria Teresa; Scuderi, Luca; Librando, Aloisa; Fenicia, Vito; Rahimi, Siavash

2018-05-02

Potential factors influencing stereopsis were investigated in patients with both refractive accommodative esotropia (RAE) and amblyopia. Pigment dispersion syndrome (PDS) is a condition where anomalous iridozonular contact leads to pigment dispersion throughout the anterior segment and the released pigment is abnormally deposited on various ocular structures. The clinical presentation of PDS is defined by the presence of pigmented cells on the corneal endothelium, an increase of pigmentation of the trabecular meshwork, and mid-periphery transillumination defects of the iris. This syndrome, more common in myopes, is usually bilateral and can be associated with ocular hypertension or glaucoma. Secondary open-angle pigmentary glaucoma (PG) can develop due to reduction of the outflow of aqueous humour and consequent increase in intraocular pressure leading to glaucomatous optic neuropathy. Diagnosis of PG is commonly between 40 and 50 years of age, occurring more frequently in men. The advent of ultrasound biomicroscopy and anterior segment optical coherence tomography has contributed to enhancing our knowledge on the condition. Typical alterations of the anterior segment are the posterior insertion of the iris and iris concavity. Treatment of PG should be initiated early to hinder disease progression, glaucomatous damage, and vision loss. Management is based on medical therapy, laser iridotomy, selective laser trabeculoplasty, and filtration procedures. The differential diagnosis of PDS with other disorders can be challenging and awareness of the condition together with meticulous ophthalmologic examination allows early diagnosis followed by appropriate management strategies. The present review is a comprehensive report on the clinical characteristics, pathogenesis, current management, and status quo of PDS and PG.

Surgical outcomes of trabeculectomy and glaucoma drainage implant for uveitic glaucoma and relationship with uveitis activity.

Science.gov (United States)

Kwon, Hye Jin; Kong, Yu Xiang George; Tao, Lingwei William; Lim, Lyndell L; Martin, Keith R; Green, Catherine; Ruddle, Jonathan; Crowston, Jonathan G

2017-07-01

This study provides ophthalmologists who manage uveitic glaucoma with important information on factors that can affect the success of surgical management of this challenging disease. This study examines surgical outcomes of trabeculectomy and glaucoma device implant (GDI) surgery for uveitic glaucoma, in particular the effect of uveitis activity on surgical outcomes. Retrospective chart review at a tertiary institution. Eighty-two cases with uveitic glaucoma (54 trabeculectomies and 28 (GDI) surgeries) performed between 1 December 2006 and 30 November 2014. Associations of factors with surgical outcomes were examined using univariate and multivariate analysis. Surgical outcomes as defined in Guidelines from World Glaucoma Association. Average follow up was 26.4 ± 21.5 months. Overall qualified success rate of the trabeculectomies was not statistically different from GDI, being 67% and 75%, respectively (P = 0.60). Primary and secondary GDI operations showed similar success rates. The most common postoperative complication was hypotony (~30%). Active uveitis at the time of operation was higher in trabeculectomy compared with GDI group (35% vs. 14%). Active uveitis at the time of surgery did not significantly increase risk of failure for trabeculectomies. Recurrence of uveitis was significantly associated with surgical failure in trabeculectomy group (odds ratio 4.8, P = 0.02) but not in GDI group. Surgical success rate of GDI was not significantly different from trabeculectomy for uveitic glaucoma in this study. Regular monitoring, early and prolonged intensive treatment of ocular inflammation is important for surgical success particularly following trabeculectomy. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

Effect of phacoemulsification on intraocular pressure in patients with primary open angle glaucoma and pseudoexfoliation glaucoma

Directory of Open Access Journals (Sweden)

Jesus Jimenez-Roman

2017-09-01

Full Text Available AIM: To compare the effect of phacoemulsification on intraocular pressure (IOP in patients with primary open angle glaucoma (POAG and pseudoexfoliation glaucoma (PXG. METHODS: A retrospective comparative case series conducted at the Glaucoma Department at the Association to Prevent Blindness in Mexico. The study enrolled consecutive patients having phacoemulsification with intraocular lens (IOL implantation and a diagnosis of POAG or PXG. Data about IOP values and number of glaucoma medications used was collected at baseline, 1, 3, 6 and 12mo postoperatively. RESULTS: The study enrolled 88 patients (88 eyes. After phacoemulsification, there was a statistically significant reduction in IOP values and glaucoma medications use compared to baseline in both POAG and PXG patients (P<0.001. In the POAG group, a 20% decrease in IOP values was evidenced, and a 56.5% reduction in the number of medications used at the one-year follow-up. The PXG group showed a 20.39%, and a 34.46% decrease in IOP and number of medications used, respectively. A significant difference in the mean ΔIOP (postoperative changes in IOP was evidenced between groups (P=0.005. The reduction of the postsurgical IOP mean values in both groups, the POAG group showed a greater reduction in IOP values compared to the PXG group. CONCLUSION: In both types of glaucoma, phacoemulsification cataract surgery can result in a significant IOP reduction (20% over a 12mo follow-up period. The number of medications used is also significantly reduced up to 12mo after surgery, especially in the PXG group.

Pars plana Ahmed valve and vitrectomy in patients with glaucoma associated with posterior segment disease.

Science.gov (United States)

Wallsh, Josh O; Gallemore, Ron P; Taban, Mehran; Hu, Charles; Sharareh, Behnam

2013-01-01

To assess the safety and efficacy of a modified technique for pars plana placement of the Ahmed valve in combination with pars plana vitrectomy in the treatment of glaucoma associated with posterior segment disease. Thirty-nine eyes with glaucoma associated with posterior segment disease underwent pars plana vitrectomy combined with Ahmed valve placement. All valves were placed in the pars plana using a modified technique, without the pars plana clip, and using a scleral patch graft. The 24 eyes diagnosed with neovascular glaucoma had an improvement in intraocular pressure from 37.6 mmHg to 13.8 mmHg and best-corrected visual acuity from 2.13 logarithm of minimum angle of resolution to 1.40 logarithm of minimum angle of resolution. Fifteen eyes diagnosed with steroid-induced glaucoma had an improvement in intraocular pressure from 27.9 mmHg to 14.1 mmHg and best-corrected visual acuity from 1.38 logarithm of minimum angle of resolution to 1.13 logarithm of minimum angle of resolution. Complications included four cases of cystic bleb formation and one case of choroidal detachment and explantation for hypotony. Ahmed valve placement through the pars plana during vitrectomy is an effective option for managing complex cases of glaucoma without the use of the pars plana clip.

Macular thickness after glaucoma filtration surgery.

Science.gov (United States)

Sesar, Antonio; Cavar, Ivan; Sesar, Anita Pusić; Geber, Mia Zorić; Sesar, Irena; Laus, Katia Novak; Vatavuk, Zoran; Mandić, Zdravko

2013-09-01

The aim of present study was to analyze early postoperative changes in the macular area using optical coherence tomography (OCT) after uncomplicated glaucoma filtration surgery. This prospective study included 32 patients (34 eyes) with open-angle glaucoma, which underwent trabeculectomy with or without use of mitomycin C. Exclusion criteria were macular edema, uveitis, age-related macular degeneration, blurred optical media, secondary glaucoma and angle-closure glaucoma. All standard clinical examinations were made before surgery, at the 2nd day, 1 week and 1 month after surgery. Tomography of the macula was performed during every examination using Cirrus HD OCT for the analysis of central subfield thickness. Results show that thickening of the macula was slightly higher 1 week and 1 month after operation in comparison with baseline end 2nd day postoperativelly. There was no significant difference in the change of macular thickness in patients who have used topical prostaglandins compared with those who have used other topical medications. Also, there was no difference in macular changes between patients treated with or without mitomycin C. In conclusion, we found a slight subclinical increase in macular thickness after uncomplicated trabeculectomy, for which we considered that was the result in reduction of intraocular pressure after glaucoma surgery. Macular thickening after glaucoma filtering surgery could be a physiological reaction to the stress of the retina caused by a sudden reduction of intraocular pressure and it is the consequence of altered relationship between capillary pressure and interstitial fluid pressure.

Self-Induced Faraday Instability Laser

Science.gov (United States)

Perego, A. M.; Smirnov, S. V.; Staliunas, K.; Churkin, D. V.; Wabnitz, S.

2018-05-01

We predict the onset of self-induced parametric or Faraday instabilities in a laser, spontaneously caused by the presence of pump depletion, which leads to a periodic gain landscape for light propagating in the cavity. As a result of the instability, continuous wave oscillation becomes unstable even in the normal dispersion regime of the cavity, and a periodic train of pulses with ultrahigh repetition rate is generated. Application to the case of Raman fiber lasers is described, in good quantitative agreement between our conceptual analysis and numerical modeling.

SQSTM1 Mutations and Glaucoma.

Directory of Open Access Journals (Sweden)

Todd E Scheetz

Full Text Available Glaucoma is the most common cause of irreversible blindness worldwide. One subset of glaucoma, normal tension glaucoma (NTG occurs in the absence of high intraocular pressure. Mutations in two genes, optineurin (OPTN and TANK binding kinase 1 (TBK1, cause familial NTG and have known roles in the catabolic cellular process autophagy. TKB1 encodes a kinase that phosphorylates OPTN, an autophagy receptor, which ultimately activates autophagy. The sequestosome (SQSTM1 gene also encodes an autophagy receptor and also is a target of TBK1 phosphorylation. Consequently, we hypothesized that mutations in SQSTM1 may also cause NTG. We tested this hypothesis by searching for glaucoma-causing mutations in a cohort of NTG patients (n = 308 and matched controls (n = 157 using Sanger sequencing. An additional 1098 population control samples were also analyzed using whole exome sequencing. A total of 17 non-synonymous mutations were detected which were not significantly skewed between cases and controls when analyzed separately, or as a group (p > 0.05. These data suggest that SQSTM1 mutations are not a common cause of NTG.

Para-hydrogen raman laser and its application to laser induced chemistry

International Nuclear Information System (INIS)

Tashiro, Hideo

1988-01-01

The report outlines the mechanism of the para-hydrogen Raman laser as a infrared light source, and its application to laser induced chemistry. The Stoke's wave number after a Raman shift is equal to the difference between the wave number of the CO 2 laser used for excitation and the rotation Raman wave number of the hydrogen molecule. A Raman laser can serve as an infrared source. CO 2 laser oscillation beam in the range of 9∼11 micrometers is selected and the frequency of infrared beam is varied by changing the wave number of the CO 2 laser beam. A problem with the Raman laser is that the Raman scatterring gain is small due to a large wavelength. In developing equipment, a special mechanism is required to solve this problem. A Raman laser comprises a CO 2 laser for excitation and multi-pulse Raman cells. The combination of a TEA oscillator and amplifiers gives CO 2 pulses with a peak power of about several tens of MW. Many heavy metal compounds including fluorides, carbonyl compounds and other organic compounds, absorb light with wavelengths in the same range as those of the Raman laser. Such compounds can be dissociated directly by applying Raman laser beams. The laser will be helpful for separation of isotopes, etc. (Nogami, K.)

Clinical observation of two operation methods for neovascular glaucoma

Directory of Open Access Journals (Sweden)

Peng Zhang

2013-11-01

Full Text Available AIM: To evaluate the clinical effect of two different surgical treatments for neovascular glaucoma(NVG.METHODS: A total of 30 NVG inpatients(30 eyesat our hospital from April 2008 to December 2011 were reviewed. Patients were divided into two groups according to the different surgical treatments. In group A, 12 cases(12 eyeswere treated with Ahmed glaucoma valve(AGVimplantation and in group B, 18 cases(18 eyeswere treated with semiconductor diode laser photocoagulation transscleral cyclophotocoagulation(TSCPC. Intraocular pressure, visual acuity and complications were compared between two groups postoperatively.RESULTS: The postoperative IOP was significantly lower in each group(PPP>0.05in IOP 1 month after surgery. Visual acuity: in group A, the visual acuity was improved in 3 eyes, unchanged in 7 eyes and worsened in 2 eyes.; in group B, the visual acuity was improved in 3 eyes, unchanged in 12 eyes and worsened in 3 eyes. Postoperative complications: in group A, eyeball pain and corneal edema were found in 5 cases(41.7%, shallow anterior chamber in 3 cases(25%, anterior chamber fibroid exudation in 2 cases(16.7%, hyphema in 3 cases(25%; in group B, eyeball pain atearly stage after surgery were found in 10 cases(55.6% , corneal edema in 11 cases(61.1%, anterior chamber fibroid exudation in 5 cases(27.8%, hyphema in 6 cases(33.3%.CONCLUSION: AGV implantation and TSCPC are both effective surgical treatment methods for NVG. AGV implantation is a filtration surgery, which is relatively safe. TSCPC is more economical and suitable for glaucoma of advanced or absolute stage.

Contributions to process monitoring by laser-induced breakdown spectroscopy

Science.gov (United States)

Rusak, David Alexander

1998-12-01

When a pulsed laser of sufficient energy and pulse duration is brought to a focus, multi-photon ionization creates free electrons in the focal volume. These electrons are accelerated in a process known as inverse Bremsstrahlung and cause collisional ionization of species in the focal volume. More charge carriers are produced and the process continues for the duration of the laser pulse. The manifestation of this process is a visible spark or plasma which typically lasts for tens of microseconds. This laser-induced plasma can serve as a source in an atomic emission experiment. Because the composition of the plasma is determined in large part by the environment in which it forms, elements in the laser target can be determined spectroscopically. The goal of a laser-induced breakdown spectroscopy (LIBS) experiment is to establish a relationship between the concentration of an element of interest in the target and the intensity of light emitted from the laser-induced plasma at a wavelength characteristic of that element. Because LIBS requires only optical access to the sample and can perform elemental determinations in solids, liquids, or gases with little sample preparation, there is interest in using it as an on-line technique for process monitoring in a number of industrial applications. However, before the technique becomes useful in industrial applications, many issues regarding instrumentation and data analysis need to be addressed in the lab. The first two chapters of this dissertation provide, respectively, the basics of the atomic emission experiment and a background of laser-induced breakdown spectroscopy. The next two chapters examine the effect of target water content on the laser-induced plasma and the use of LIBS for analysis of aqueous samples. Chapter 5 describes construction of a fiber optic LIBS probe and its use to study temporal electron number density evolution in plasmas formed on different metals. Chapter 6 is a study of excitation, vibrational

Ultrasensitive detection of target analyte-induced aggregation of gold nanoparticles using laser-induced nanoparticle Rayleigh scattering.

Science.gov (United States)

Lin, Jia-Hui; Tseng, Wei-Lung

2015-01-01

Detection of salt- and analyte-induced aggregation of gold nanoparticles (AuNPs) mostly relies on costly and bulky analytical instruments. To response this drawback, a portable, miniaturized, sensitive, and cost-effective detection technique is urgently required for rapid field detection and monitoring of target analyte via the use of AuNP-based sensor. This study combined a miniaturized spectrometer with a 532-nm laser to develop a laser-induced Rayleigh scattering technique, allowing the sensitive and selective detection of Rayleigh scattering from the aggregated AuNPs. Three AuNP-based sensing systems, including salt-, thiol- and metal ion-induced aggregation of the AuNPs, were performed to examine the sensitivity of laser-induced Rayleigh scattering technique. Salt-, thiol-, and metal ion-promoted NP aggregation were exemplified by the use of aptamer-adsorbed, fluorosurfactant-stabilized, and gallic acid-capped AuNPs for probing K(+), S-adenosylhomocysteine hydrolase-induced hydrolysis of S-adenosylhomocysteine, and Pb(2+), in sequence. Compared to the reported methods for monitoring the aggregated AuNPs, the proposed system provided distinct advantages of sensitivity. Laser-induced Rayleigh scattering technique was improved to be convenient, cheap, and portable by replacing a diode laser and a miniaturized spectrometer with a laser pointer and a smart-phone. Using this smart-phone-based detection platform, we can determine whether or not the Pb(2+) concentration exceed the maximum allowable level of Pb(2+) in drinking water. Copyright © 2014 Elsevier B.V. All rights reserved.

Spectroscopy of beryllium-like nitrogen ions by laser-induced recombination

International Nuclear Information System (INIS)

Uhlenberg, G.

1996-04-01

The following topics were dealt with: Rydberg spectroscopy of beryllium-like nitrogen (N 3+ ) by laser-induced recombination, transition enrgies, Rydberg level shift, configuration interaction, laser intensity effect, laser band width

The medical management of glaucoma | Marais | South African ...

African Journals Online (AJOL)

Glaucoma is one of the leading causes of blindness worldwide. The main characteristic features include optic disc cupping, visual field loss, and in most instances a raised intraocular pressure. Primary open angle glaucoma accounts for nearly two thirds of all cases, while angle closure glaucoma contributes the majority of ...

Genetic modification of glaucoma associated phenotypes between AKXD-28/Ty and DBA/2J mice

Directory of Open Access Journals (Sweden)

Zabaleta Adriana

2001-01-01

Full Text Available Abstract Background Glaucoma is a common disease but its molecular etiology is poorly understood. It involves retinal ganglion cell death and optic nerve damage that is often associated with elevated intraocular pressure. Identifying genes that modify glaucoma associated phenotypes is likely to provide insights to mechanisms of glaucoma. We previously reported glaucoma in DBA/2J mice caused by recessive alleles at two loci, isa and ipd, that cause iris stromal atrophy and iris pigment dispersion, respectively. A approach for identifying modifier genes is to study the effects of specific mutations in different mouse strains. When the phenotypic effect of a mutation is modified upon its introduction into a new strain, crosses between the parental strains can be used to identify modifier genes. The purpose of this study was to determine if the effects of the DBA/2J derived isa and ipd loci are modified in strain AKXD-28/Ty. Results AKXD-28/Ty mice develop glaucoma characterized by intraocular pressure elevation, retinal ganglion loss, and optic nerve excavation. In AKXD-28/Ty, isa causes an iris stromal atrophy phenotype as in DBA/2J. However, the iris pigment dispersion phenotype associated with ipd in DBA/2J does not occur in AKXD-28/Ty. Additionally, a greater severity and speed of retinal and optic nerve damage following intraocular pressure elevation in AKXD-28/Ty compared to DBA/2J mice suggests that AKXD-28/Ty is more susceptible to pressure-induced cell death. Conclusions The consequences of the ipd and isa mutations are modified in the AKXD-28/Ty background. These strains provide a resource for the identification of modifier genes that modulate pigment dispersion and susceptibility to pressure-induced cell death.

Laser-induced diffusion decomposition in Fe–V thin-film alloys

Energy Technology Data Exchange (ETDEWEB)

Polushkin, N.I., E-mail: nipolushkin@fc.ul.pt [Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Instituto de Ciência e Engenharia de Materiais e Superfícies, 1049-001 Lisboa (Portugal); Duarte, A.C.; Conde, O. [Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa (Portugal); Instituto de Ciência e Engenharia de Materiais e Superfícies, 1049-001 Lisboa (Portugal); Alves, E. [Associação Euratom/IST e Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Barradas, N.P. [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, 2695-066 Bobadela LRS (Portugal); García-García, A.; Kakazei, G.N.; Ventura, J.O.; Araujo, J.P. [Departamento de Física, Universidade do Porto e IFIMUP, 4169-007 Porto (Portugal); Oliveira, V. [Instituto de Ciência e Engenharia de Materiais e Superfícies, 1049-001 Lisboa (Portugal); Instituto Superior de Engenharia de Lisboa, 1959-007 Lisboa (Portugal); Vilar, R. [Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Instituto de Ciência e Engenharia de Materiais e Superfícies, 1049-001 Lisboa (Portugal)

2015-05-01

Highlights: • Irradiation of an Fe–V alloy by femtosecond laser triggers diffusion decomposition. • The decomposition occurs with strongly enhanced (∼4 orders) atomic diffusivity. • This anomaly is associated with the metallic glassy state achievable under laser quenching. • The ultrafast diffusion decomposition is responsible for laser-induced ferromagnetism. - Abstract: We investigate the origin of ferromagnetism induced in thin-film (∼20 nm) Fe–V alloys by their irradiation with subpicosecond laser pulses. We find with Rutherford backscattering that the magnetic modifications follow a thermally stimulated process of diffusion decomposition, with formation of a-few-nm-thick Fe enriched layer inside the film. Surprisingly, similar transformations in the samples were also found after their long-time (∼10{sup 3} s) thermal annealing. However, the laser action provides much higher diffusion coefficients (∼4 orders of magnitude) than those obtained under standard heat treatments. We get a hint that this ultrafast diffusion decomposition occurs in the metallic glassy state achievable in laser-quenched samples. This vitrification is thought to be a prerequisite for the laser-induced onset of ferromagnetism that we observe.

UV laser-induced cross-linking in peptides

Science.gov (United States)

Leo, Gabriella; Altucci, Carlo; Bourgoin-Voillard, Sandrine; Gravagnuolo, Alfredo M.; Esposito, Rosario; Marino, Gennaro; Costello, Catherine E.; Velotta, Raffaele; Birolo, Leila

2013-01-01

RATIONALE The aim of this study was to demonstrate, and to characterize by high resolution mass spectrometry, that it is possible to preferentially induce covalent cross-links in peptides by using high energy femtosecond UV laser pulses. The cross-link is readily formed only when aromatic amino acids are present in the peptide sequence. METHODS Three peptides, xenopsin, angiotensin I, interleukin, individually or in combination, were exposed to high energy femtosecond UV laser pulses, either alone or in the presence of spin trapping molecules, the reaction products being characterized by high resolution mass spectrometry. RESULTS High resolution mass spectrometry and spin trapping strategies showed that cross-linking occurs readily, proceeds via a radical mechanism, and is the highly dominant reaction, proceeding without causing significant photo-damage in the investigated range of experimental parameters. CONCLUSIONS High energy femtosecond UV laser pulses can be used to induce covalent cross-links between aromatic amino acids in peptides, overcoming photo-oxidation processes, that predominate as the mean laser pulse intensity approaches illumination conditions achievable with conventional UV light sources. PMID:23754800

Laser-induced damage study of polymer PMMA

International Nuclear Information System (INIS)

Mansour, N.

2001-01-01

This article presents the results of bulk laser-induced damage measurements in polymer PMMA at 532 nm and 1064 nm for nanosecond laser pulses. The damage thresholds were measured for focused spot sizes ranging over two orders of magnitude. In this work, self-focusing effects were verified to be absent by measurements of breakdown thresholds using both linearly and circularly polarized light. At both 1064 nm and 532 nm, the dependence of the breakdown field, E B , on the spot size, ω, was empirically determined to be E B = C/√ω, where C depends on the wavelength. The extracted value for C(λ) at 1064 nm is larger by a factor of 5 than at 532 nm. Possible reasons for this strong dispersion and mechanism for laser-induced damage in polymer materials will be discussed

Laser induced white lighting of tungsten filament

Science.gov (United States)

Strek, W.; Tomala, R.; Lukaszewicz, M.

2018-04-01

The sustained bright white light emission of thin tungsten filament was induced under irradiation with focused beam of CW infrared laser diode. The broadband emission centered at 600 nm has demonstrated the threshold behavior on excitation power. Its intensity increased non-linearly with excitation power. The emission occurred only from the spot of focused beam of excitation laser diode. The white lighting was accompanied by efficient photocurrent flow and photoelectron emission which both increased non-linearly with laser irradiation power.

Anticlotting agents and the surgical management of glaucoma.

Science.gov (United States)

Sozeri, Yasemin; Salim, Sarwat

2018-03-01

A large subset of patients with glaucoma uses anticlotting agents. No standardized guidelines currently exist for managing these agents in the specific perioperative setting of glaucoma surgery. The present review focuses on currently available anticlotting agents, their influence on hemorrhagic complications following glaucoma surgery, and management strategies for their use in the perioperative period RECENT FINDINGS: Anticlotting agents increase the risk of perioperative hemorrhagic complications following glaucoma surgery. Other factors that increase that risk have been identified as well, including the type of glaucoma surgery, preoperative intraocular pressure, postoperative hypotony, previous ocular surgeries, and race. Although general guidelines in the perioperative management of blood thinning agents exist, the best way to apply these guidelines specifically to glaucoma surgery remains unclear. Blood thinners are widely used and can increase the risk of hemorrhagic complications in patients undergoing glaucoma surgery. Managing these agents in the perioperative setting is challenging and should be done in collaboration with the patient's primary care provider, hematologist, or cardiologist. Management strategies should be tailored to each individual's risk of hemorrhage versus thromboembolism. Additionally, surgical plans can be modified to help minimize hemorrhagic outcomes, especially in patients who are deemed to be at high risk for perioperative bleeding.

Involvement of genetic variants associated with primary open-angle glaucoma in pathogenic mechanisms and family history of glaucoma.

Science.gov (United States)

Mabuchi, Fumihiko; Sakurada, Yoichi; Kashiwagi, Kenji; Yamagata, Zentaro; Iijima, Hiroyuki; Tsukahara, Shigeo

2015-03-01

To investigate the associations between the non-intraocular pressure (IOP)-related genetic variants (genetic variants associated with vulnerability of the optic nerve independent of IOP) and primary open-angle glaucoma (POAG), including normal-tension glaucoma (NTG) and high-tension glaucoma (HTG), and between the non-IOP-related genetic variants and a family history of glaucoma. Case-control study. Japanese patients with NTG (n = 213) and HTG (n = 212) and 191 control subjects were genotyped for 5 non-IOP-related genetic variants predisposing to POAG near the SRBD1, ELOVL5, CDKN2B/CDKN2B-AS1, SIX1/SIX6, and ATOH7 genes. The load of these genetic variants was compared between the control subjects and patients with NTG or HTG and between the POAG patients with and without a family history of glaucoma. The total number of POAG risk alleles and the product of the odds ratios (POAG risk) of these genetic variants were significantly larger (P product of the odds ratios increased (P = .012 and P = .047, respectively). Non-IOP-related genetic variants contribute to the pathogenesis of HTG as well as NTG. A positive family history of glaucoma in cases of POAG is thought to reflect the influence of genetic variants predisposing to POAG. Copyright © 2015 Elsevier Inc. All rights reserved.

Normal tension glaucoma and Alzheimer disease

DEFF Research Database (Denmark)

Bach-Holm, Daniella; Kessing, Svend Vedel; Mogensen, Ulla Brasch

2012-01-01

Purpose: To investigate whether normal tension glaucoma (NTG) is associated with increased risk of developing dementia/Alzheimer disease (AD). Methods: A total of 69 patients with NTG were identified in the case note files in the Glaucoma Clinic, University Hospital of Copenhagen (Rigshospitalet...

Laser Induced Selective Activation For Subsequent Autocatalytic Electroless Plating

DEFF Research Database (Denmark)

Zhang, Yang

. The third hypothesis is that the activation and rinsing process can be described by diffusion. This hypothesis is proved using Fick’s diffusion laws combined with the short-time-plating experiment. The influence of laser parameters on the surface structure is investigated for Nd:YAG, UV, and fiber lasers......The subject of this PhD thesis is “Laser induced selective activation for subsequent autocatalytic electroless plating.” The objective of the project is to investigate the process chains for micro structuring of polymer surfaces for selective micro metallization. Laser induced selective activation...... (LISA) is introduced and studied as a new technique for producing 3D moulded interconnect devices (3D-MIDs). This technique enables the metallization of polymer surface modified by laser and subsequently activated by a PdCl2/SnCl2 system. Various technologies exist on an industrial level...

Micropulse diode laser trabeculoplasty -- 180-degree treatment.

Science.gov (United States)

Rantala, Elina; Välimäki, Juha

2012-08-01

To evaluate the outcome of 180° micropulse diode laser trabeculoplasty (MDLT) in patients with open-angle glaucoma. A retrospective review of 40 eyes of 29 MDLT-treated patients with a minimum follow-up time of 6 months. Successful outcome was defined as follows: (i) a ≥20% or (ii) a ≥3-mmHg decrease of intraocular pressure (IOP), no further need for laser- or incisional surgery and the number of glaucoma medication was the same or less than preoperative. These definitions will from now on be referred to as definition one and definition two. Life-table analysis showed an overall success rate of 2.5% (1/40) and 7.5% (3/40) (according to definitions one and two, respectively) after up to 19 months of follow-up. The average time for failure was by definition one 2.9 months (standard deviation, SD ± 3.5, range 1-12 months) and by definition two 3.3 months (SD ± 3.9, range 1-16 months). There were no intra- or postoperative complications caused by MDLT. Postoperative inflammatory reaction, cells and flare, was scanty. Our results suggest that 180° MDLT is a safe but ineffective treatment in patients with open-angle glaucoma. © 2010 The Authors. Acta Ophthalmologica © 2010 Acta Ophthalmologica Scandinavica Foundation.

Infrared laser induced organic reactions. 2. Laser vs. thermal inducment of unimolecular and hydrogen bromide catalyzed bimolecular dehydration of alcohols

International Nuclear Information System (INIS)

Danen, W.C.

1979-01-01

It has been demonstrated that a mixture of reactant molecules can be induced by pulsed infrared laser radiation to react via a route which is totally different from the pathway resulting from heating the mixture at 300 0 C. The high-energy unimolecular elimination of H 2 O from ethanol in the presence of 2-propanol and HBr can be selectively induced with a pulsed CO 2 laser in preference to either a lower energy bimolecular HBr-catalyzed dehydration or the more facile dehydration of 2-propanol. Heating the mixture resulted in the almost exclusive reaction of 2-propanol to produce propylene. It was demonstrated that the bimolecular ethanol + HBr reaction cannot be effectively induced by the infrared laser radiation as evidenced by the detrimental effect on the yield of ethylene as the HBr pressure was increased. The selective, nonthermal inducement of H 2 O elimination from vibrationally excited ethanol in the presence of 2-propanol required relatively low reactant pressures. At higher pressures intermolecular V--V energy transfer allowed the thermally more facile dehydration from 2-propanol to become the predominant reaction channel

Relation between Glaucoma and Sensorineural Hearing Loss

Directory of Open Access Journals (Sweden)

A Mollasadeghi

2008-01-01

Full Text Available Introduction: Glaucoma is one of the leading causes of blindness throughout the world. Some studies have suggested a relationship between glaucoma and sensorineural hearing loss, while others have found no evidence of an association. We performed a study to determine whether there is a significant difference in hearing of patients with glaucoma and a match control population. Methods: In this cross-sectional study, from February, 2005 till April, 2006, 44 patients with glaucoma were studied. The age range was between 15 to 60 years. After taking a complete medical history, those suffering from presbycusis, history of exposure to ototoxic drugs and substances and history of ear surgery were excluded from the study. All of the patients were cases of open-angle glaucoma, and were surveyed separately for normal-pressure glaucoma. Then complete audiometric tests (PTA, SDS, SRT, Impedance were conducted for all of them, and the results compared with a control group. Results: There was no statistically significant difference between the case group and control group in PTA, SDS, and SRT, except for Normal Tension Glaucoma (NTG. There wasn't any statistically significant difference between two groups with respect to age, gender, and history of diseases. In the NTG group, significant difference was seen only in high frequencies. Conclusion: As mentioned, there was a statistically significant difference between NTG group and control group. It is therefore recommended to conduct complete audiometric tests and histopathologic examinations in this group for early detection of hearing loss and application of rehabilitative measures.

Ahmed glaucoma valve implant: surgical technique and complications.

Science.gov (United States)

Riva, Ivano; Roberti, Gloria; Oddone, Francesco; Konstas, Anastasios Gp; Quaranta, Luciano

2017-01-01

Implantation of Ahmed glaucoma valve is an effective surgical technique to reduce intraocular pressure in patients affected with glaucoma. While in the past, the use of this device was reserved to glaucoma refractory to multiple filtration surgical procedures, up-to-date mounting experience has encouraged its use also as a primary surgery for selected cases. Implantation of Ahmed glaucoma valve can be challenging for the surgeon, especially in patients who already underwent previous multiple surgeries. Several tips have to be acquired by the surgeon, and a long learning curve is always needed. Although the valve mechanism embedded in the Ahmed glaucoma valve decreases the risk of postoperative hypotony-related complications, it does not avoid the need of a careful follow-up. Complications related to this type of surgery include early and late postoperative hypotony, excessive capsule fibrosis around the plate, erosion of the tube or plate edge, and very rarely infection. The aim of this review is to describe surgical technique for Ahmed glaucoma valve implantation and to report related complications.

Imaging of the optic disk in caring for patients with glaucoma: ophthalmoscopy and photography remain the gold standard.

Science.gov (United States)

Spaeth, George L; Reddy, Swathi C

2014-01-01

Optic disk imaging is integral to the diagnosis and treatment of patients with glaucoma. We discuss the various forms of imaging the optic nerve, including ophthalmoscopy, photography, and newer imaging modalities, including optical coherence tomography (OCT), confocal scanning laser ophthalmoscopy (HRT), and scanning laser polarimetry (GDx), specifically highlighting their benefits and disadvantages. We argue that ophthalmoscopy and photography remain the gold standard of imaging due to portability, ease of interpretation, and the presence of a large database of images for comparison. Copyright © 2014 Elsevier Inc. All rights reserved.

Effect of the R dependence of laser-induced polarizability on molecular dynamic alignment in an intense femtosecond laser field

International Nuclear Information System (INIS)

Chen Jianxin; Cui Xiaomei; Huang Bomin; Wu Hongchun; Zhuo Shuangmu

2006-01-01

In the rotation equation of the angle θ between the molecular axis and the laser polarization direction, the dependence of laser-induced polarizability on the molecular internuclear distance R is considered. The effect of the R dependence of laser-induced polarizability on molecular dynamic alignment in an intense femtosecond laser field is investigated with 20 and 100 fs laser pulses for N 2 molecules and with 60 and 100 fs laser pulses for Br 2 molecules at intensities of 5x10 14 W cm -2 and 5x10 15 W cm -2 . This effect exists and only occurs during the dissociative process after the molecule is ionized. It enhances the degrees of molecular dynamic alignment and is more significant in reorienting the angular distributions of molecules towards the laser polarization direction in the conditions of high laser intensity and short pulse length. Compared with the N 2 molecule, the effect of the R dependence of laser-induced polarizability on molecular dynamic alignment for Br 2 is stronger. The reasons are presented and discussed

Interference of laser-induced resonances in the continuous structures of a helium atom

International Nuclear Information System (INIS)

Magunov, A I; Strakhova, S I

2003-01-01

Coherent effects in the interference of overlapping laser-induced resonances in helium atoms are considered. The simultaneous action of single-mode radiation of the 294-nm second harmonic of a cw dye laser and a 1064-nm Nd:YAG laser on helium atoms provides the overlap of two resonances induced by transitions from the 1s2s 1 S and 1s4s 1 S helium levels. The shape of the overlapping laser-induced resonances in the rotating-wave approximation is described by analytic expressions, which depend on the laser radiation intensities and the ratio of laser frequencies. (nonlinear optical phenomena)

Impact of mechanical stress induced in silica vacuum windows on laser-induced damage.

Science.gov (United States)

Gingreau, Clémence; Lanternier, Thomas; Lamaignère, Laurent; Donval, Thierry; Courchinoux, Roger; Leymarie, Christophe; Néauport, Jérôme

2018-04-15

At the interface between vacuum and air, optical windows must keep their optical properties, despite being subjected to mechanical stress. In this Letter, we investigate the impact of such stress on the laser-induced damage of fused silica windows at the wavelength of 351 nm in the nanosecond regime. Different stress values, from 1 to 30 MPa, both tensile and compressive, were applied. No effect of the stress on the laser-induced damage was evidenced.

Glaucoma progression detection with frequency doubling technology (FDT) compared to standard automated perimetry (SAP) in the Groningen Longitudinal Glaucoma Study.

Science.gov (United States)

Wesselink, Christiaan; Jansonius, Nomdo M

2017-09-01

To determine the usefulness of frequency doubling perimetry (FDT) for progression detection in glaucoma, compared to standard automated perimetry (SAP). Data were used from 150 eyes of 150 glaucoma patients from the Groningen Longitudinal Glaucoma Study. After baseline, SAP was performed approximately yearly; FDT every other year. First and last visit had to contain both tests. Using linear regression, progression velocities were calculated for SAP (Humphrey Field Analyzer) mean deviation (MD) and FDT MD and the number of test locations with a total deviation probability below p glaucoma progression in patients who cannot perform SAP reliably. © 2017 The Authors Ophthalmic & Physiological Optics © 2017 The College of Optometrists.

Regional Retinal Ganglion Cell Axon Loss in a Murine Glaucoma Model.

Science.gov (United States)

Schaub, Julie A; Kimball, Elizabeth C; Steinhart, Matthew R; Nguyen, Cathy; Pease, Mary E; Oglesby, Ericka N; Jefferys, Joan L; Quigley, Harry A

2017-05-01

To determine if retinal ganglion cell (RGC) axon loss in experimental mouse glaucoma is uniform in the optic nerve. Experimental glaucoma was induced for 6 weeks with a microbead injection model in CD1 (n = 78) and C57BL/6 (B6, n = 68) mice. From epoxy-embedded sections of optic nerve 1 to 2 mm posterior to the globe, total nerve area and regional axon density (axons/1600 μm2) were measured in superior, inferior, nasal, and temporal zones. Control eyes of CD1 mice have higher axon density and more total RGCs than control B6 mice eyes. There were no significant differences in control regional axon density in all mice or by strain (all P > 0.2, mixed model). Exposure to elevated IOP caused loss of RGC in both strains. In CD1 mice, axon density declined without significant loss of nerve area, while B6 mice had less density loss, but greater decrease in nerve area. Axon density loss in glaucoma eyes was not significantly greater in any region in either mouse strain (both P > 0.2, mixed model). In moderately damaged CD1 glaucoma eyes, and CD1 eyes with the greatest IOP elevation exposure, density loss differed by region (P = 0.05, P = 0.03, mixed model) with the greatest loss in the temporal and superior regions, while in severely injured B6 nerves superior loss was greater than inferior loss (P = 0.01, mixed model, Bonferroni corrected). There was selectively greater loss of superior and temporal optic nerve axons of RGCs in mouse glaucoma at certain stages of damage. Differences in nerve area change suggest non-RGC responses differ between mouse strains.

Characterization of hard coatings produced by laser cladding using laser-induced breakdown spectroscopy technique

Energy Technology Data Exchange (ETDEWEB)

Varela, J.A.; Amado, J.M.; Tobar, M.J.; Mateo, M.P.; Yañez, A.; Nicolas, G., E-mail: gines@udc.es

2015-05-01

Highlights: • Chemical mapping and profiling by laser-induced breakdown spectroscopy (LIBS) of coatings produced by laser cladding. • Production of laser clads using tungsten carbide (WC) and nickel based matrix (NiCrBSi) powders. • Calibration by LIBS of hardfacing alloys with different WC concentrations. - Abstract: Protective coatings with a high abrasive wear resistance can be obtained from powders by laser cladding technique, in order to extend the service life of some industrial components. In this work, laser clad layers of self-fluxing NiCrBSi alloy powder mixed with WC powder have been produced on stainless steel substrates of austenitic type (AISI 304) in a first step and then chemically characterized by laser-induced breakdown spectroscopy (LIBS) technique. With the suitable laser processing parameters (mainly output power, beam scan speed and flow rate) and powders mixture proportions between WC ceramics and NiCrBSi alloys, dense pore free layers have been obtained on single tracks and on large areas with overlapped tracks. The results achieved by LIBS technique and applied for the first time to the analysis of laser clads provided the chemical composition of the tungsten carbides in metal alloy matrix. Different measurement modes (multiple point analyses, depth profiles and chemical maps) have been employed, demonstrating the usefulness of LIBS technique for the characterization of laser clads based on hardfacing alloys. The behavior of hardness can be explained by LIBS maps which evidenced the partial dilution of some WC spheres in the coating.

Remote triggering of high voltage systems by laser-induced plasmas

CSIR Research Space (South Africa)

West, NJ

2008-08-01

Full Text Available -induced plasma was found to play a significant role in the breakdown process – best results being obtained when the laser was focused in the centre of the gap. Finally, the shape of the laser-induced arc is dependant on the applied electric field. When the field...

Design of low cost glaucoma screening

NARCIS (Netherlands)

Niessen, A. G.; Langerhorst, C. T.; Geijssen, H. C.; Greve, E. L.

1997-01-01

In 1991 the Netherlands Glaucoma Patient Association organized a glaucoma screening survey. This survey was designed to evaluate the effectiveness of a low cost screening setting. During a screening period of 8 days, 1259 subjects over the age of 49 years were examined by a team of

Retinal oxygen saturation before and after glaucoma surgery.

Science.gov (United States)

Nitta, Eri; Hirooka, Kazuyuki; Shimazaki, Takeru; Sato, Shino; Ukegawa, Kaori; Nakano, Yuki; Tsujikawa, Akitaka

2017-08-01

This study compared retinal vessel oxygen saturation before and after glaucoma surgery. Retinal oxygen saturation in glaucoma patients was measured using a non-invasive spectrophotometric retinal oximeter. Adequate image quality was found in 49 of the 108 consecutive glaucoma patients recruited, with 30 undergoing trabeculectomy, 11 EX-PRESS and eight trabeculotomy. Retinal oxygen saturation measurements in the retinal arterioles and venules were performed at 1 day prior to and at approximately 10 days after surgery. Statistical analysis was performed using a Student's t-test. After glaucoma surgery, intraocular pressure (IOP) decreased from 19.8 ± 7.7 mmHg to 9.0 ± 5.7 mmHg (p glaucoma surgery had an effect on the retinal venous oxygen saturation. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Methylphenidate (Ritalin-associated Cataract and Glaucoma

Directory of Open Access Journals (Sweden)

Chao-Kung Lu

2006-12-01

Full Text Available Methylphenidate hydrochloride (Ritalin is the drug of choice for attention deficit hyperactivity disorder (ADHD. However, an association of Ritalin with glaucoma has been reported. We report a case of Ritalin-associated cataract and glaucoma. A 10-year-old boy was diagnosed with ADHD and had received methylphenidate hydrochloride, 60 mg/day for 2 years. He presented with blurred vision. Best-corrected visual acuity was 6/60 in both eyes. Ocular examinations revealed intraocular pressure (IOP of 30 mmHg under medication, dense posterior subcapsular opacity of lens, pale disc with advanced cupping, and marked constriction of visual field. Despite maximal anti-glaucomatous medication, IOP still could not be controlled. The patient then received combined cataract and glaucoma surgery. Visual acuity improved and IOP was within normal limits in both eyes postoperatively. Large dose of methylphenidate may cause cataract and glaucoma. The mechanism remains unclear. Doctors should be aware of the possible ocular side effects of methylphenidate.

Supersonic laser-induced jetting of aluminum micro-droplets

International Nuclear Information System (INIS)

Zenou, M.; Sa'ar, A.; Kotler, Z.

2015-01-01

The droplet velocity and the incubation time of pure aluminum micro-droplets, printed using the method of sub-nanosecond laser induced forward transfer, have been measured indicating the formation of supersonic laser-induced jetting. The incubation time and the droplet velocity were extracted by measuring a transient electrical signal associated with droplet landing on the surface of the acceptor substrate. This technique has been exploited for studying small volume droplets, in the range of 10–100 femto-litters for which supersonic velocities were measured. The results suggest elastic propagation of the droplets across the donor-to-acceptor gap, a nonlinear deposition dynamics on the surface of the acceptor and overall efficient energy transfer from the laser beam to the droplets

Supersonic laser-induced jetting of aluminum micro-droplets

Energy Technology Data Exchange (ETDEWEB)

Zenou, M. [Racah Institute of Physics and the Harvey M. Kruger Family Center for Nano-science and Nanotechnology, The Hebrew University of Jerusalem, 91904 Jerusalem (Israel); Additive Manufacturing Lab, Orbotech Ltd., P.O. Box 215, 81101 Yavne (Israel); Sa' ar, A. [Racah Institute of Physics and the Harvey M. Kruger Family Center for Nano-science and Nanotechnology, The Hebrew University of Jerusalem, 91904 Jerusalem (Israel); Kotler, Z. [Additive Manufacturing Lab, Orbotech Ltd., P.O. Box 215, 81101 Yavne (Israel)

2015-05-04

The droplet velocity and the incubation time of pure aluminum micro-droplets, printed using the method of sub-nanosecond laser induced forward transfer, have been measured indicating the formation of supersonic laser-induced jetting. The incubation time and the droplet velocity were extracted by measuring a transient electrical signal associated with droplet landing on the surface of the acceptor substrate. This technique has been exploited for studying small volume droplets, in the range of 10–100 femto-litters for which supersonic velocities were measured. The results suggest elastic propagation of the droplets across the donor-to-acceptor gap, a nonlinear deposition dynamics on the surface of the acceptor and overall efficient energy transfer from the laser beam to the droplets.

Biodegradable microfabricated plug-filters for glaucoma drainage devices.

Science.gov (United States)

Maleki, Teimour; Chitnis, Girish; Park, Jun Hyeong; Cantor, Louis B; Ziaie, Babak

2012-06-01

We report on the development of a batch fabricated biodegradable truncated-cone-shaped plug filter to overcome the postoperative hypotony in nonvalved glaucoma drainage devices. Plug filters are composed of biodegradable polymers that disappear once wound healing and bleb formation has progressed past the stage where hypotony from overfiltration may cause complications in the human eye. The biodegradable nature of device eliminates the risks associated with permanent valves that may become blocked or influence the aqueous fluid flow rate in the long term. The plug-filter geometry simplifies its integration with commercial shunts. Aqueous humor outflow regulation is achieved by controlling the diameter of a laser-drilled through-hole. The batch compatible fabrication involves a modified SU-8 molding to achieve truncated-cone-shaped pillars, polydimethylsiloxane micromolding, and hot embossing of biodegradable polymers. The developed plug filter is 500 μm long with base and apex plane diameters of 500 and 300 μm, respectively, and incorporates a laser-drilled through-hole with 44-μm effective diameter in the center.

Laser resonant ionization spectroscopy and laser-induced resonant fluorescence spectra of samarium atom

International Nuclear Information System (INIS)

Jin, Changtai

1995-01-01

We have measured new high-lying levels of Sm atom by two-colour resonant photoionisation spectroscopy; we have observed the isotope shifts of Sm atom by laser-induced resonant fluorescence spectroscopy; the lifetime of eight low-lying levels of Sm atom were measured by using pulsed laser-Boxcar technique in atomic beam.

The role of matricellular proteins in glaucoma.

LENUS (Irish Health Repository)

Wallace, Deborah M

2014-07-01

Glaucoma is an optic neuropathy affecting approximately 60million people worldwide and is the second most common cause of irreversible blindness. Elevated intraocular pressure (IOP) is the main risk factor for developing glaucoma and is caused by impaired aqueous humor drainage through the trabecular meshwork (TM) and Schlemm\\'s canal (SC). In primary open angle glaucoma (POAG), this elevation in IOP in turn leads to deformation at the optic nerve head (ONH) specifically at the lamina cribrosa (LC) region where there is also a deposition of extracellular matrix (ECM) molecules such as collagen and fibronectin. Matricellular proteins are non-structural secreted glycoproteins that help cells communicate with their surrounding ECM. This family of proteins includes connective tissue growth factor (CTGF), also known as CCN2, thrombospondins (TSPs), secreted protein acidic and rich in cysteine (SPARC), periostin, osteonectin, and Tenascin-C and -X and other ECM proteins. All members appear to play a role in fibrosis and increased ECM deposition. Most are widely expressed in tissues particularly in the TM and ONH and deficiency of TSP1 and SPARC have been shown to lower IOP in mouse models of glaucoma through enhanced outflow facility. The role of these proteins in glaucoma is emerging as some have an association with the pathophysiology of the TM and LC regions and might therefore be potential targets for therapeutic intervention in glaucoma.

Q-switched Nd:YAG/V:YAG microchip 1338 nm laser for laser-induced breakdown spectroscopy

Science.gov (United States)

Šulc, Jan; Jelínková, Helena; Nejezchleb, Karel; Škoda, Václav

2017-12-01

Q-switched microchip laser emitting radiation at wavelength 1338nm was tested as a radiation source for laser induced breakdown spectroscopy (LIBS). This laser used sandwich crystal which combined in one piece the cooling part (undoped YAG crystal 4mm long), the active laser part (Nd:YAG crystal 12mm long), and the saturable absorber (V:YAG crystal 0.7mm long). The diameter of this crystal was 5 mm. The microchip resonator consisted of dielectric mirrors directly deposited on the monolith crystal surfaces. The pump mirror (HT @ 808 nm, HR @ 1.3 ¹m) was placed on the undoped YAG part. The output coupler (R = 90% @ 1338 nm) was placed on the V:YAG part. The fibre-coupled 808nm pumping laser diode was operating in pulsed regime (rep. rate 250 Hz, pulse width 300 ¹s, pulse energy 6 mJ). Using this pumping, stable and high reproducible Q-switched pulses were generated at wavelength 1338 nm. Pulse length was 6.2 ns (FWHM) and the mean output power was 33mW. The single pulse energy and peak power was 0.13mJ and 21kW, respectively. Laser was operating in fundamental TEM00 mode. The laser radiation was focused on a tested sample using single plano-convex lens (focal length 75 mm). The focal spot radius was 40 ¹m. The corresponding peak-power density was 0.83GW/cm2. The laser induced break-down was successfully reached and corresponding laser-induced plasma spectra were recorded for set of metallic elements (Cu, Ag, Au, In, Zn, Al, Fe, Ni, Cr) and alloys (Sn-Pb solder, duralumin, stainless-steel, brass). To record the spectra, StellarNet BLACK-Comet concave grating CCD-based spectrometer was used without any special collimation optics. Thanks to used laser wavelength far from the detector sensitivity, no special filtering was needed to overcome the CCD dazzling. The constructed laser could significantly improve repletion-rate of up-to-date LIBS devices.

Glaucoma and Driving: On-Road Driving Characteristics

Science.gov (United States)

Wood, Joanne M.; Black, Alex A.; Mallon, Kerry; Thomas, Ravi; Owsley, Cynthia

2016-01-01

Purpose To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment. Methods Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years) with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB) and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years). On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire. Results Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability. Conclusions Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness. PMID:27472221

Demographic features of subjects with congenital glaucoma

Science.gov (United States)

Tamçelik, Nevbahar; Atalay, Eray; Bolukbasi, Selim; Çapar, Olgu; Ozkok, Ahmet

2014-01-01

Context: Congenital glaucoma is a potentially blinding ocular disease of the childhood. Identification of the possible associated risk factors and may be helpful for prevention or early detection of this public health problem. Aims: To demonstrate the demographic features of congenital glaucoma subjects. Setting and Design: The charts of congenital glaucoma patients referred to Tamcelik Glaucoma Center were retrospectively reviewed through the dates of 2000 and 2013. Materials and Methods: Analyzed data included diagnosis, age at first presentation, symptoms at first presentation, laterality of the disease, sex, presence of consanguinity, family history of congenital glaucoma, maturity of the fetus at delivery, and maternal age at conception. Statistical Analysis Used: Statistical Package for Social Sciences (SPSS) version 19.0 by IBM (SPSS Inc, Chicago, Illinois, USA) was used to compare the mean of continuous variables with Student's t-test and analysis of variance (ANOVA) and χ2 test was used to test differences in proportions of categorical variables. Results: The data of 600 eyes of 311 patients were analyzed. The distribution of primary and secondary congenital glaucoma among the patients were 63.3% (n = 197) and 36.7% (n = 114), respectively. Of the 311 patients, 57.2% (n = 178) were male and 42.8% (n = 133) were female. The overall frequency of bilateral disease was 92.3% (n = 287). Overall rate of consanguinity and positive family history was 45.3% (n = 141) and 21.2% (n = 66), respectively. Conclusions: Bilateral disease in this study was more common than previously reported studies. Positive family history was more frequent in primary congenital glaucoma although not statistically significant. PMID:24881602

Glaucoma and Driving: On-Road Driving Characteristics.

Directory of Open Access Journals (Sweden)

Joanne M Wood

Full Text Available To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment.Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years. On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire.Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability.Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness.

Glaucoma and Driving: On-Road Driving Characteristics.

Science.gov (United States)

Wood, Joanne M; Black, Alex A; Mallon, Kerry; Thomas, Ravi; Owsley, Cynthia

2016-01-01

To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment. Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years) with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB) and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years). On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire. Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability. Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness.

Impurity monitoring by laser-induced fluorescence techniques

International Nuclear Information System (INIS)

Gelbwachs, J.A.

1984-01-01

Laser-induced fluorescence spectroscopy can provide a highly sensitive and selective means of detecting atomic and ionic impurities. Because the photodetector can be physically isolated from the laser-excited region, these techniques can be applied to monitoring in hostile environments. The basic concepts behind fluorescence detection are reviewed. Saturated optical excitation is shown to maximize impurity atom emission yield while mitigating effects of laser intensity fluctuations upon absolute density calibration. Monitoring in high- and low-pressure monitoring environments is compared. Methods to improve detection sensitivity by luminescence background suppression are presented

Neurodegeneration severity can be predicted from early microglia alterations monitored in vivo in a mouse model of chronic glaucoma

Directory of Open Access Journals (Sweden)

Alejandra Bosco

2015-05-01

Full Text Available Microglia serve key homeostatic roles, and respond to neuronal perturbation and decline with a high spatiotemporal resolution. The course of all chronic CNS pathologies is thus paralleled by local microgliosis and microglia activation, which begin at early stages of the disease. However, the possibility of using live monitoring of microglia during early disease progression to predict the severity of neurodegeneration has not been explored. Because the retina allows live tracking of fluorescent microglia in their intact niche, here we investigated their early changes in relation to later optic nerve neurodegeneration. To achieve this, we used the DBA/2J mouse model of inherited glaucoma, which develops progressive retinal ganglion cell degeneration of variable severity during aging, and represents a useful model to study pathogenic mechanisms of retinal ganglion cell decline that are similar to those in human glaucoma. We imaged CX3CR1+/GFP microglial cells in vivo at ages ranging from 1 to 5 months by confocal scanning laser ophthalmoscopy (cSLO and quantified cell density and morphological activation. We detected early microgliosis at the optic nerve head (ONH, where axonopathy first manifests, and could track attenuation of this microgliosis induced by minocycline. We also observed heterogeneous and dynamic patterns of early microglia activation in the retina. When the same animals were aged and analyzed for the severity of optic nerve pathology at 10 months of age, we found a strong correlation with the levels of ONH microgliosis at 3 to 4 months. Our findings indicate that live imaging and monitoring the time course and levels of early retinal microgliosis and microglia activation in glaucoma could serve as indicators of future neurodegeneration severity.

Imaging femtosecond laser-induced electronic excitation in glass

International Nuclear Information System (INIS)

Mao Xianglei; Mao, Samuel S.; Russo, Richard E.

2003-01-01

While substantial progress has been achieved in understanding laser ablation on the nanosecond and picosecond time scales, it remains a considerable challenge to elucidate the underlying mechanisms during femtosecond laser material interactions. We present experimental observations of electronic excitation inside a wide band gap glass during single femtosecond laser pulse (100 fs, 800 nm) irradiation. Using a femtosecond time-resolved imaging technique, we measured the evolution of a laser-induced electronic plasma inside the glass and calculated the electron number density to be on the order of 10 19 cm -3

Femtosecond versus nanosecond laser machining: comparison of induced stresses and structural changes in silicon wafers

International Nuclear Information System (INIS)

Amer, M.S.; El-Ashry, M.A.; Dosser, L.R.; Hix, K.E.; Maguire, J.F.; Irwin, Bryan

2005-01-01

Laser micromachining has proven to be a very successful tool for precision machining and microfabrication with applications in microelectronics, MEMS, medical device, aerospace, biomedical, and defense applications. Femtosecond (FS) laser micromachining is usually thought to be of minimal heat-affected zone (HAZ) local to the micromachined feature. The assumption of reduced HAZ is attributed to the absence of direct coupling of the laser energy into the thermal modes of the material during irradiation. However, a substantial HAZ is thought to exist when machining with lasers having pulse durations in the nanosecond (NS) regime. In this paper, we compare the results of micromachining a single crystal silicon wafer using a 150-femtosecond and a 30-nanosecond lasers. Induced stress and amorphization of the silicon single crystal were monitored using micro-Raman spectroscopy as a function of the fluence and pulse duration of the incident laser. The onset of average induced stress occurs at lower fluence when machining with the femtosecond pulse laser. Induced stresses were found to maximize at fluence of 44 J cm -2 and 8 J cm -2 for nanosecond and femtosecond pulsed lasers, respectively. In both laser pulse regimes, a maximum induced stress is observed at which point the induced stress begins to decrease as the fluence is increased. The maximum induced stress was comparable at 2.0 GPa and 1.5 GPa for the two lasers. For the nanosecond pulse laser, the induced amorphization reached a plateau of approximately 20% for fluence exceeding 22 J cm -2 . For the femtosecond pulse laser, however, induced amorphization was approximately 17% independent of the laser fluence within the experimental range. These two values can be considered nominally the same within experimental error. For femtosecond laser machining, some effect of the laser polarization on the amount of induced stress and amorphization was also observed