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Bettina Hohberger - One of the best experts on this subject based on the ideXlab platform.
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Glaucoma confrontation visual field test using bagolini striated glasses a new screening method for detecting visual field defects
Ophthalmology, 2016Co-Authors: Katja Kara, Anselm Junemann, Robert Rejdak, Bettina HohbergerAbstract:INTRODUCTION. Glaucoma diagnosis is based on elevated intraocular pressure, altered morphology of the optic disc, and perimetric visual field defects. Next to funduscopy and optical coherence tomography, perimetric data are important. In developing countries, large parts of the population have only limited access to medical care. Especially in these cases, a quick and affordable method for detecting visual field defects would be desirable. The aim of this study was to investigate the potential use of Bagolini striated glasses in detecting Glaucomatous visual field defects. MATERIALS AND METHODS . Ninety subjects of the Erlangen Glaucoma Register (ISSN 2191-5008, CS-2011. ClinicalTrials.gov, Identifier: NCT00494923) were tested using the confrontation visual field test with Bagolini striated glasses [10 normals, 17 ocular hypertensions (OHT), 31 preperimetric open-angle Glaucomas (preOAG), 16 normal tension Glaucomas (NTG), 16 open-angle Glaucomas (OAG)]. All probands underwent standard ophthalmological examination including slit-lamp biomicroscopy, funduscopy, and Goldmann-tonometry. Additionally, standard white-on-white perimetry and measurements of the global retinal nerve fibre layer (RNFL) of the optic disc were performed. RESULTS. 1. All normals, all OHTs, and 96% of preOAGs showed normal Bagolini test results. 2. 74% of NTGs and 73% of OAGs yielded pathological Bagolini test results. 3. Specificity of patients with normal visual fields was 98% and sensitivity was 73–80%. 4. Visual field defects resulted in altered Bagolini test results. 5. Localised visual field defects were detected in 78% (NTG) and 80% (OAG) using Bagolini striated glasses. CONCLUSIONS. Glaucoma-related visual field defects can be detected by confrontation visual field testing using Bagolini striated glasses. This quick, easily performed, and affordable method can be used as a bedside test and is suitable as a screening method for persons in developing countries.
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Glaucoma: Confrontation visual field test using Bagolini striated glasses — a new screening method for detecting visual field defects
Ophthalmology, 2016Co-Authors: Katja Kara, Anselm Junemann, Robert Rejdak, Bettina HohbergerAbstract:INTRODUCTION. Glaucoma diagnosis is based on elevated intraocular pressure, altered morphology of the optic disc, and perimetric visual field defects. Next to funduscopy and optical coherence tomography, perimetric data are important. In developing countries, large parts of the population have only limited access to medical care. Especially in these cases, a quick and affordable method for detecting visual field defects would be desirable. The aim of this study was to investigate the potential use of Bagolini striated glasses in detecting Glaucomatous visual field defects. MATERIALS AND METHODS . Ninety subjects of the Erlangen Glaucoma Register (ISSN 2191-5008, CS-2011. ClinicalTrials.gov, Identifier: NCT00494923) were tested using the confrontation visual field test with Bagolini striated glasses [10 normals, 17 ocular hypertensions (OHT), 31 preperimetric open-angle Glaucomas (preOAG), 16 normal tension Glaucomas (NTG), 16 open-angle Glaucomas (OAG)]. All probands underwent standard ophthalmological examination including slit-lamp biomicroscopy, funduscopy, and Goldmann-tonometry. Additionally, standard white-on-white perimetry and measurements of the global retinal nerve fibre layer (RNFL) of the optic disc were performed. RESULTS. 1. All normals, all OHTs, and 96% of preOAGs showed normal Bagolini test results. 2. 74% of NTGs and 73% of OAGs yielded pathological Bagolini test results. 3. Specificity of patients with normal visual fields was 98% and sensitivity was 73–80%. 4. Visual field defects resulted in altered Bagolini test results. 5. Localised visual field defects were detected in 78% (NTG) and 80% (OAG) using Bagolini striated glasses. CONCLUSIONS. Glaucoma-related visual field defects can be detected by confrontation visual field testing using Bagolini striated glasses. This quick, easily performed, and affordable method can be used as a bedside test and is suitable as a screening method for persons in developing countries.
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temporal contrast sensitivity a potential parameter for Glaucoma progression especially in advanced stages
Ophthalmology, 2016Co-Authors: Pia V Rutrecht, Anselm Junemann, Katharina Brehmer, Jan Kremers, Folkert K Horn, Bettina HohbergerAbstract:INTRODUCTION. Previously it could be shown that temporal contrast sensitivity is affected by Glaucoma and maximally influenced after 25-Hz adaptation in normals. This study investigated different kinds of 25-Hz temporal contrast adaptation on TCS in patients with ocular hypertension, preperimetric primary open-angle Glaucoma, and perimetric open-angle Glaucoma. Additionally, correlations of measured data with parameters of Glaucoma diagnostic were done and assessed for the potential use of TCS as a parameter for Glaucoma progression. MATERIALS AND METHODS. One hundred and four subjects were included: 44 normals, 14 ocular hypertensions, 11 preperimetric primary open-angle Glaucomas, and 35 perimetric open-angle Glaucomas. Using the Erlangen Flicker Test, temporal contrast sensitivity was measured without adaptation, after pre-adaptation and after pre- and re-adaptations at 25 Hz. Reliability analyses were done. RESULTS. All test strategies showed high reliability (a-Cronbach’s > 0.86). In normals, age-dependency of temporal contrast sensitivity without adaptation (p = 0.052) and after pre- and re-adaptation (p = 0.008) was observed. Temporal contrast sensitivity is significantly reduced after pre-adaptation for all subjects (p < 0.001). Reduction of temporal contrast sensitivity after pre- and re-adaptations was significant in all groups (p < 0.001), but it was smaller than after single pre-adaptation (p < 0.001). Temporal contrast sensitivity without adaptation was significantly reduced in patients with perimetric Glaucoma (p = 0.040) but not in patients with ocular hypertension and preperimetric Glaucoma. Correlation analyses yielded a significant correlation between temporal contrast sensitivity without adaptation and mean defect (p = 0.003, r = –0.329), loss variance (p = 0.027, r = –0.256), and retinal nerve fibre layer thickness (p < 0.001, r = 0.413) for all subjects and between temporal contrast sensitivity after pre-adaptation and mean defect (p = 0.045, r = –0.239). CONCLUSIONS. Temporal contrast sensitivity seems to be affected in perimetric Glaucoma with an overall reduction after adaptation. Significant correlations of temporal contrast sensitivity with perimetric and morphologic parameters offer new aspects of its potential use as a Glaucoma progressions marker, especially in advanced stages when perimetric diagnosis is limited.
Anselm Junemann - One of the best experts on this subject based on the ideXlab platform.
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Glaucoma confrontation visual field test using bagolini striated glasses a new screening method for detecting visual field defects
Ophthalmology, 2016Co-Authors: Katja Kara, Anselm Junemann, Robert Rejdak, Bettina HohbergerAbstract:INTRODUCTION. Glaucoma diagnosis is based on elevated intraocular pressure, altered morphology of the optic disc, and perimetric visual field defects. Next to funduscopy and optical coherence tomography, perimetric data are important. In developing countries, large parts of the population have only limited access to medical care. Especially in these cases, a quick and affordable method for detecting visual field defects would be desirable. The aim of this study was to investigate the potential use of Bagolini striated glasses in detecting Glaucomatous visual field defects. MATERIALS AND METHODS . Ninety subjects of the Erlangen Glaucoma Register (ISSN 2191-5008, CS-2011. ClinicalTrials.gov, Identifier: NCT00494923) were tested using the confrontation visual field test with Bagolini striated glasses [10 normals, 17 ocular hypertensions (OHT), 31 preperimetric open-angle Glaucomas (preOAG), 16 normal tension Glaucomas (NTG), 16 open-angle Glaucomas (OAG)]. All probands underwent standard ophthalmological examination including slit-lamp biomicroscopy, funduscopy, and Goldmann-tonometry. Additionally, standard white-on-white perimetry and measurements of the global retinal nerve fibre layer (RNFL) of the optic disc were performed. RESULTS. 1. All normals, all OHTs, and 96% of preOAGs showed normal Bagolini test results. 2. 74% of NTGs and 73% of OAGs yielded pathological Bagolini test results. 3. Specificity of patients with normal visual fields was 98% and sensitivity was 73–80%. 4. Visual field defects resulted in altered Bagolini test results. 5. Localised visual field defects were detected in 78% (NTG) and 80% (OAG) using Bagolini striated glasses. CONCLUSIONS. Glaucoma-related visual field defects can be detected by confrontation visual field testing using Bagolini striated glasses. This quick, easily performed, and affordable method can be used as a bedside test and is suitable as a screening method for persons in developing countries.
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Glaucoma: Confrontation visual field test using Bagolini striated glasses — a new screening method for detecting visual field defects
Ophthalmology, 2016Co-Authors: Katja Kara, Anselm Junemann, Robert Rejdak, Bettina HohbergerAbstract:INTRODUCTION. Glaucoma diagnosis is based on elevated intraocular pressure, altered morphology of the optic disc, and perimetric visual field defects. Next to funduscopy and optical coherence tomography, perimetric data are important. In developing countries, large parts of the population have only limited access to medical care. Especially in these cases, a quick and affordable method for detecting visual field defects would be desirable. The aim of this study was to investigate the potential use of Bagolini striated glasses in detecting Glaucomatous visual field defects. MATERIALS AND METHODS . Ninety subjects of the Erlangen Glaucoma Register (ISSN 2191-5008, CS-2011. ClinicalTrials.gov, Identifier: NCT00494923) were tested using the confrontation visual field test with Bagolini striated glasses [10 normals, 17 ocular hypertensions (OHT), 31 preperimetric open-angle Glaucomas (preOAG), 16 normal tension Glaucomas (NTG), 16 open-angle Glaucomas (OAG)]. All probands underwent standard ophthalmological examination including slit-lamp biomicroscopy, funduscopy, and Goldmann-tonometry. Additionally, standard white-on-white perimetry and measurements of the global retinal nerve fibre layer (RNFL) of the optic disc were performed. RESULTS. 1. All normals, all OHTs, and 96% of preOAGs showed normal Bagolini test results. 2. 74% of NTGs and 73% of OAGs yielded pathological Bagolini test results. 3. Specificity of patients with normal visual fields was 98% and sensitivity was 73–80%. 4. Visual field defects resulted in altered Bagolini test results. 5. Localised visual field defects were detected in 78% (NTG) and 80% (OAG) using Bagolini striated glasses. CONCLUSIONS. Glaucoma-related visual field defects can be detected by confrontation visual field testing using Bagolini striated glasses. This quick, easily performed, and affordable method can be used as a bedside test and is suitable as a screening method for persons in developing countries.
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temporal contrast sensitivity a potential parameter for Glaucoma progression especially in advanced stages
Ophthalmology, 2016Co-Authors: Pia V Rutrecht, Anselm Junemann, Katharina Brehmer, Jan Kremers, Folkert K Horn, Bettina HohbergerAbstract:INTRODUCTION. Previously it could be shown that temporal contrast sensitivity is affected by Glaucoma and maximally influenced after 25-Hz adaptation in normals. This study investigated different kinds of 25-Hz temporal contrast adaptation on TCS in patients with ocular hypertension, preperimetric primary open-angle Glaucoma, and perimetric open-angle Glaucoma. Additionally, correlations of measured data with parameters of Glaucoma diagnostic were done and assessed for the potential use of TCS as a parameter for Glaucoma progression. MATERIALS AND METHODS. One hundred and four subjects were included: 44 normals, 14 ocular hypertensions, 11 preperimetric primary open-angle Glaucomas, and 35 perimetric open-angle Glaucomas. Using the Erlangen Flicker Test, temporal contrast sensitivity was measured without adaptation, after pre-adaptation and after pre- and re-adaptations at 25 Hz. Reliability analyses were done. RESULTS. All test strategies showed high reliability (a-Cronbach’s > 0.86). In normals, age-dependency of temporal contrast sensitivity without adaptation (p = 0.052) and after pre- and re-adaptation (p = 0.008) was observed. Temporal contrast sensitivity is significantly reduced after pre-adaptation for all subjects (p < 0.001). Reduction of temporal contrast sensitivity after pre- and re-adaptations was significant in all groups (p < 0.001), but it was smaller than after single pre-adaptation (p < 0.001). Temporal contrast sensitivity without adaptation was significantly reduced in patients with perimetric Glaucoma (p = 0.040) but not in patients with ocular hypertension and preperimetric Glaucoma. Correlation analyses yielded a significant correlation between temporal contrast sensitivity without adaptation and mean defect (p = 0.003, r = –0.329), loss variance (p = 0.027, r = –0.256), and retinal nerve fibre layer thickness (p < 0.001, r = 0.413) for all subjects and between temporal contrast sensitivity after pre-adaptation and mean defect (p = 0.045, r = –0.239). CONCLUSIONS. Temporal contrast sensitivity seems to be affected in perimetric Glaucoma with an overall reduction after adaptation. Significant correlations of temporal contrast sensitivity with perimetric and morphologic parameters offer new aspects of its potential use as a Glaucoma progressions marker, especially in advanced stages when perimetric diagnosis is limited.
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Stereoscopic visual evoked potentials in normal subjects and patients with open-angle Glaucomas
Graefe's Archive for Clinical and Experimental Ophthalmology, 2004Co-Authors: Antonio Bergua, Anselm Junemann, Folkert K Horn, Peter Martus, Matthias KorthAbstract:Purpose To evaluate stereoscopic visual evoked potentials (S-VEP) in normal controls and in patients with Glaucomatous optic nerve damage. Methods Computer-generated dynamic random-dot stereograms were used to elicit cortical visual evoked potentials using wireless electric liquid crystal shutter glasses. Normal subjects ( n =22) and patients with Glaucoma ( n =22) were investigated using five different disparities from 9 to 40 arc min. Statistical dependency of measurements with different stimulus at identical patients was adjusted for. Results Peak times of onset and offset response of S-VEP can be significantly delayed in Glaucomas. A general linear regression model confirmed that differences between patients and normals depend on disparity. S-VEP onset shows no significant difference between controls and Glaucomas at 9 arc min disparity. At high disparities, however, peak time of the onset response was significantly ( p
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the full field flicker test in Glaucomas influence of intraocular pressure and pattern of visual field losses
Graefes Archive for Clinical and Experimental Ophthalmology, 1999Co-Authors: Folkert K Horn, Anselm Junemann, Isabel M Velten, Matthias KorthAbstract:· Background: The purpose of this study was to evaluate how temporal contrast sensitivity (TCS) determined with full-field flicker stimuli is influenced by intraocular pressure and whether TCS is reduced in Glaucoma patients with diffuse perimetric losses as well as in patients with localized visual field deficits. · Methods: TCS was determined with sinusoidally flickering light (37.1 Hz) in a full-field bowl. Perimetric mean defect (MD) and cumulative defect curves (Octopus G1) were used to distinguish between patients with localized and diffuse field deficits. Normal subjects (296), low-tension Glaucoma patients (98) and open-angle Glaucoma patients with previously elevated intraocular pressure (541) were classified into five subgroups taking into account the depth of their visual field losses. · Results: No significant correlation between full-field flicker sensitivity and prevailing intraocular pressure was found in normals (Y=1.36+0.006 X) or in patients (Y=0.95–0.0002 X). Analyses of validity at a predefined specificity of 90% reveal a reduction of TCS in patients with early (MD 20 dB). The lack of TCS is similar in open-angle Glaucomas and in field-loss-matched normal-tension Glaucoma patients. · Conclusions: Significantly reduced TCS in patients with early diffuse perimetric losses as well as in those showing localized visual field defects indicates that localized damages can be associated with general deterioration of the ability to perceive flickering stimuli. Thus, this flicker test can be performed in a full-field bowl with no need for fixation. Considering its other clinical qualities (photopic conditions, low influence of prevailing intraocular pressure and media opacity) the test may be a useful, convenient supplementary procedure in Glaucoma screening.
Katja Kara - One of the best experts on this subject based on the ideXlab platform.
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Glaucoma confrontation visual field test using bagolini striated glasses a new screening method for detecting visual field defects
Ophthalmology, 2016Co-Authors: Katja Kara, Anselm Junemann, Robert Rejdak, Bettina HohbergerAbstract:INTRODUCTION. Glaucoma diagnosis is based on elevated intraocular pressure, altered morphology of the optic disc, and perimetric visual field defects. Next to funduscopy and optical coherence tomography, perimetric data are important. In developing countries, large parts of the population have only limited access to medical care. Especially in these cases, a quick and affordable method for detecting visual field defects would be desirable. The aim of this study was to investigate the potential use of Bagolini striated glasses in detecting Glaucomatous visual field defects. MATERIALS AND METHODS . Ninety subjects of the Erlangen Glaucoma Register (ISSN 2191-5008, CS-2011. ClinicalTrials.gov, Identifier: NCT00494923) were tested using the confrontation visual field test with Bagolini striated glasses [10 normals, 17 ocular hypertensions (OHT), 31 preperimetric open-angle Glaucomas (preOAG), 16 normal tension Glaucomas (NTG), 16 open-angle Glaucomas (OAG)]. All probands underwent standard ophthalmological examination including slit-lamp biomicroscopy, funduscopy, and Goldmann-tonometry. Additionally, standard white-on-white perimetry and measurements of the global retinal nerve fibre layer (RNFL) of the optic disc were performed. RESULTS. 1. All normals, all OHTs, and 96% of preOAGs showed normal Bagolini test results. 2. 74% of NTGs and 73% of OAGs yielded pathological Bagolini test results. 3. Specificity of patients with normal visual fields was 98% and sensitivity was 73–80%. 4. Visual field defects resulted in altered Bagolini test results. 5. Localised visual field defects were detected in 78% (NTG) and 80% (OAG) using Bagolini striated glasses. CONCLUSIONS. Glaucoma-related visual field defects can be detected by confrontation visual field testing using Bagolini striated glasses. This quick, easily performed, and affordable method can be used as a bedside test and is suitable as a screening method for persons in developing countries.
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Glaucoma: Confrontation visual field test using Bagolini striated glasses — a new screening method for detecting visual field defects
Ophthalmology, 2016Co-Authors: Katja Kara, Anselm Junemann, Robert Rejdak, Bettina HohbergerAbstract:INTRODUCTION. Glaucoma diagnosis is based on elevated intraocular pressure, altered morphology of the optic disc, and perimetric visual field defects. Next to funduscopy and optical coherence tomography, perimetric data are important. In developing countries, large parts of the population have only limited access to medical care. Especially in these cases, a quick and affordable method for detecting visual field defects would be desirable. The aim of this study was to investigate the potential use of Bagolini striated glasses in detecting Glaucomatous visual field defects. MATERIALS AND METHODS . Ninety subjects of the Erlangen Glaucoma Register (ISSN 2191-5008, CS-2011. ClinicalTrials.gov, Identifier: NCT00494923) were tested using the confrontation visual field test with Bagolini striated glasses [10 normals, 17 ocular hypertensions (OHT), 31 preperimetric open-angle Glaucomas (preOAG), 16 normal tension Glaucomas (NTG), 16 open-angle Glaucomas (OAG)]. All probands underwent standard ophthalmological examination including slit-lamp biomicroscopy, funduscopy, and Goldmann-tonometry. Additionally, standard white-on-white perimetry and measurements of the global retinal nerve fibre layer (RNFL) of the optic disc were performed. RESULTS. 1. All normals, all OHTs, and 96% of preOAGs showed normal Bagolini test results. 2. 74% of NTGs and 73% of OAGs yielded pathological Bagolini test results. 3. Specificity of patients with normal visual fields was 98% and sensitivity was 73–80%. 4. Visual field defects resulted in altered Bagolini test results. 5. Localised visual field defects were detected in 78% (NTG) and 80% (OAG) using Bagolini striated glasses. CONCLUSIONS. Glaucoma-related visual field defects can be detected by confrontation visual field testing using Bagolini striated glasses. This quick, easily performed, and affordable method can be used as a bedside test and is suitable as a screening method for persons in developing countries.
Simon W M John - One of the best experts on this subject based on the ideXlab platform.
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vitamin b3 modulates mitochondrial vulnerability and prevents Glaucoma in aged mice
Science, 2017Co-Authors: Peter A Williams, Jeffrey M Harder, Nicole E Foxworth, Kelly E Cochran, Vivek M Philip, Vittorio Porciatti, Oliver Smithies, Simon W M JohnAbstract:Glaucomas are neurodegenerative diseases that cause vision loss, especially in the elderly. The mechanisms initiating Glaucoma and driving neuronal vulnerability during normal aging are unknown. Studying Glaucoma-prone mice, we show that mitochondrial abnormalities are an early driver of neuronal dysfunction, occurring before detectable degeneration. Retinal levels of nicotinamide adenine dinucleotide (NAD+, a key molecule in energy and redox metabolism) decrease with age and render aging neurons vulnerable to disease-related insults. Oral administration of the NAD+ precursor nicotinamide (vitamin B3), and/or gene therapy (driving expression of Nmnat1, a key NAD+-producing enzyme), was protective both prophylactically and as an intervention. At the highest dose tested, 93% of eyes did not develop Glaucoma. This supports therapeutic use of vitamin B3 in Glaucoma and potentially other age-related neurodegenerations.
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Absence of Glaucoma in DBA/2J mice homozygous for wild-type versions of Gpnmb and Tyrp1
BMC Genetics, 2007Co-Authors: Gareth R. Howell, Richard T. Libby, Jeffrey K. Marchant, Lawriston A. Wilson, I. M. Cosma, Richard S. Smith, Michael G. Anderson, Simon W M JohnAbstract:Background The Glaucomas are a common but incompletely understood group of diseases. DBA/2J mice develop a pigment liberating iris disease that ultimately causes elevated intraocular pressure (IOP) and Glaucoma. We have shown previously that mutations in two genes, Gpnmb and Tyrp1, initiate the iris disease. However, mechanisms involved in the subsequent IOP elevation and optic nerve degeneration remain unclear.
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absence of Glaucoma in dba 2j mice homozygous for wild type versions of gpnmb and tyrp1
BMC Genetics, 2007Co-Authors: Gareth R. Howell, Simon W M John, Richard T. Libby, Jeffrey K. Marchant, Lawriston A. Wilson, I. M. Cosma, Richard S. Smith, Michael G. AndersonAbstract:Background The Glaucomas are a common but incompletely understood group of diseases. DBA/2J mice develop a pigment liberating iris disease that ultimately causes elevated intraocular pressure (IOP) and Glaucoma. We have shown previously that mutations in two genes, Gpnmb and Tyrp1, initiate the iris disease. However, mechanisms involved in the subsequent IOP elevation and optic nerve degeneration remain unclear.
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Interacting loci cause severe iris atrophy and Glaucoma in DBA/2J mice
Nature Genetics, 1999Co-Authors: Bo Chang, Richard S. Smith, Michael G. Anderson, Norman L Hawes, Adriana Zabaleta, Olga Savinova, Thomas H Roderick, John R. Heckenlively, Muriel T Davisson, Simon W M JohnAbstract:Glaucomas are a major cause of blindness^ 1 . Visual loss typically involves retinal ganglion cell death and optic nerve atrophy subsequent to a pathologic elevation of intraocular pressure (IOP). Some human Glaucomas are associated with anterior segment abnormalities such as pigment dispersion syndrome (PDS) and iris atrophy with associated synechiae^ 2 . The primary causes of these abnormalities are unknown, and their aetiology is poorly understood. We recently characterized a mouse strain (DBA/2J) that develops Glaucoma subsequent to anterior segment changes including pigment dispersion and iris atrophy^ 3 . Using crosses between mouse strains DBA/2J (D2) and C57BL/6J (B6), we now show there are two chromosomal regions that contribute to the anterior segment changes and Glaucoma. Progeny homozygous for the D2 allele of one locus on chromosome 6 (called ipd ) develop an iris pigment dispersion phenotype similar to human PDS. ipd resides on a region of mouse chromosome 6 with conserved synteny to a region of human chromosome 7q that is associated with human PDS ( ref. 4 ). Progeny homozygous for the D2 allele of a different locus on chromosome 4 (called isa ) develop an iris stromal atrophy phenotype (ISA). The Tyrp1 gene is a candidate for isa and likely causes ISA via a mechanism involving pigment production. Progeny homozygous for the D2 alleles of both ipd and isa develop an earlier onset and more severe disease involving pigment dispersion and iris stromal atrophy.
Matthias Korth - One of the best experts on this subject based on the ideXlab platform.
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Stereoscopic visual evoked potentials in normal subjects and patients with open-angle Glaucomas
Graefe's Archive for Clinical and Experimental Ophthalmology, 2004Co-Authors: Antonio Bergua, Anselm Junemann, Folkert K Horn, Peter Martus, Matthias KorthAbstract:Purpose To evaluate stereoscopic visual evoked potentials (S-VEP) in normal controls and in patients with Glaucomatous optic nerve damage. Methods Computer-generated dynamic random-dot stereograms were used to elicit cortical visual evoked potentials using wireless electric liquid crystal shutter glasses. Normal subjects ( n =22) and patients with Glaucoma ( n =22) were investigated using five different disparities from 9 to 40 arc min. Statistical dependency of measurements with different stimulus at identical patients was adjusted for. Results Peak times of onset and offset response of S-VEP can be significantly delayed in Glaucomas. A general linear regression model confirmed that differences between patients and normals depend on disparity. S-VEP onset shows no significant difference between controls and Glaucomas at 9 arc min disparity. At high disparities, however, peak time of the onset response was significantly ( p
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the full field flicker test in Glaucomas influence of intraocular pressure and pattern of visual field losses
Graefes Archive for Clinical and Experimental Ophthalmology, 1999Co-Authors: Folkert K Horn, Anselm Junemann, Isabel M Velten, Matthias KorthAbstract:· Background: The purpose of this study was to evaluate how temporal contrast sensitivity (TCS) determined with full-field flicker stimuli is influenced by intraocular pressure and whether TCS is reduced in Glaucoma patients with diffuse perimetric losses as well as in patients with localized visual field deficits. · Methods: TCS was determined with sinusoidally flickering light (37.1 Hz) in a full-field bowl. Perimetric mean defect (MD) and cumulative defect curves (Octopus G1) were used to distinguish between patients with localized and diffuse field deficits. Normal subjects (296), low-tension Glaucoma patients (98) and open-angle Glaucoma patients with previously elevated intraocular pressure (541) were classified into five subgroups taking into account the depth of their visual field losses. · Results: No significant correlation between full-field flicker sensitivity and prevailing intraocular pressure was found in normals (Y=1.36+0.006 X) or in patients (Y=0.95–0.0002 X). Analyses of validity at a predefined specificity of 90% reveal a reduction of TCS in patients with early (MD 20 dB). The lack of TCS is similar in open-angle Glaucomas and in field-loss-matched normal-tension Glaucoma patients. · Conclusions: Significantly reduced TCS in patients with early diffuse perimetric losses as well as in those showing localized visual field defects indicates that localized damages can be associated with general deterioration of the ability to perceive flickering stimuli. Thus, this flicker test can be performed in a full-field bowl with no need for fixation. Considering its other clinical qualities (photopic conditions, low influence of prevailing intraocular pressure and media opacity) the test may be a useful, convenient supplementary procedure in Glaucoma screening.
