42 results on '"Arden ratio"'
Search Results
2. Electrooculography
- Author
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Creel, Donnell, Yu, Minzhong, Yu, Minzhong, editor, Creel, Donnell, editor, and Iannaccone, Alessandro, editor
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- 2019
- Full Text
- View/download PDF
3. Electrodiagnostic Tests
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Jägle, Herbert, Zierhut, Manfred, editor, Pavesio, Carlos, editor, Ohno, Shigeaki, editor, Orefice, Fernando, editor, and Rao, Narsing A., editor
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- 2016
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4. Arden Ratio
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Schmidt-Erfurth, Ursula, editor and Kohnen, Thomas, editor
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- 2018
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5. ISCEV Standard for clinical electro-oculography (2017 update).
- Author
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Constable, Paul, Bach, Michael, Frishman, Laura, Jeffrey, Brett, and Robson, Anthony
- Abstract
The clinical electro-oculogram (EOG) is an electrophysiological test of the outer retina and retinal pigment epithelium (RPE) in which changes in the electrical potential across the RPE are recorded during successive periods of dark and light adaptation. This document presents the 2017 EOG Standard from the International Society for Clinical Electrophysiology of Vision (ISCEV: ). This standard has been reorganized and updated to include an explanation of the mechanism of the EOG, but without substantive changes to the testing protocol from the previous version published in 2011. It describes methods for recording the EOG in clinical applications and gives detailed guidance on technical requirements, practical issues and reporting of results with the main clinical measure (the Arden ratio) now termed the light peak:dark trough ratio. The standard is intended to promote consistent quality of testing and reporting within and between clinical centers. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
6. The influence of iris color and retina pigment epithelium melanin on allergic rhinitis.
- Author
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Dereköy, Sefa, Kenar, Fethullah, Yavaş, Güliz Fatma, Küsbeci, Tuncay, Öztürk, Faruk, and Ayçiçek, Abdullah
- Subjects
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ALLERGIC rhinitis , *IRIS (Eye) - Abstract
Objective: The purpose of this case control study is to establish the influence of iris color and retina pigment epithelium melanin on allergic rhinitis. Methods: Ninety-nine subjects diagnosed prospectively as allergic rhinitis and 85 control subjects were included in the study. Color of iris was recorded after ophthalmic examination. Electro-oculographic measurement was done after pupil dilatation and Arden ratios were recorded. Results: Mean age was 29.44±9.8 years in subject with allergic rhinitis and 32.67±12.9 years in control subjects (p>0.05). Measured mean Arden ratio was 158.22±29.4 in subjects with allergic rhinitis and 179.34±29.3 in normal subjects (p<0.05). In control group, Arden ratio was significantly higher in eyes with brown iris (p<0.05). In subjects with allergic rhinitis, Arden ratio was significantly lower in brown eyes (p<0.05). Conclusion: An association between allergic rhinitis and melanin content of iris and retina pigment epithelium was found. It can be speculated that pigment-producing system may play a role in the pathogenesis of the allergic rhinitis. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
7. The effects of gender and age on the range of the normal human electro-oculogram.
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Thavikulwat, Alisa, Lopez, Patrick, Caruso, Rafael, and Jeffrey, Brett
- Abstract
Purpose: To define the normal ranges for the slow oscillations (SO) and fast oscillations (FO) of the electro-oculogram (EOG) recorded to International Society for Clinical Electrophysiology of Vision (ISCEV) standards. The effects of age and gender on the EOG ranges were examined. Methods: ISCEV standard SOs and FOs were recorded from 121 subjects (51 % male) aged from 7 to 72 years. Study variables for the SO were dark trough (DT) and light peak (LP) amplitudes (µV), times to DT and LP (min), and the Arden ratio (LP/DT amplitude). The FO was fit by a sine wave and peak-to-peak amplitude (µV), phase (°), and peak-to-trough (PT) ratios derived. The effects of age, gender and pupil size on EOG parameters were examined by multiple regression analysis. Results: The average Arden ratio was 2.5. Arden ratio decreased with age at a rate of 0.13 per decade of age ( R = 0.14, P < 0.0001). The 5th percentile of the Arden ratio decreased from 2.0 to 1.7 between 10 and 60 years of age. Median time to LP was 9 min (interquartile range 8-9 min). Time to LP was age-dependent and increased by 2 min for subjects over 55 years of age compared with those less than 25 years. EOG amplitudes were greater in women than in men ( P < 0.005). The average PT ratio was 1.18, which was not affected by age or gender. Time to reach the light trough of the FO was 40 s, which increased with age (1.1 s/decade). No correlation was observed between Arden ratio and PT ratio. Conclusions: The major strength of this study is the definition of the normal range and associated lower limits of ISCEV standard EOGs based on recordings from 121 subjects balanced by gender and spanning the 1st through 8th decades of life. Decreased Arden ratio and increased time to LP are associated with aging, which is likely due to the intricate mechanisms involved in generation of the light rise. Differences between the FO and SO with respect to the effects of aging are consistent with separate generation of these two EOG signals. [ABSTRACT FROM AUTHOR]
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- 2015
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8. NORMAL ELECTROOCULOGRAPHY IN BEST DISEASE AND AUTOSOMAL RECESSIVE BESTROPHINOPATHY
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Kamron N. Khan, Michel Michaelides, Graham E. Holder, Anthony G. Robson, Andrew R. Webster, Farrah Islam, and Anthony T. Moore
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Adult ,Male ,0301 basic medicine ,medicine.medical_specialty ,Eye Movements ,genetic structures ,DNA Mutational Analysis ,Dark Adaptation ,Fundus (eye) ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Retinal Diseases ,Reference Values ,Ophthalmology ,Genotype ,Electroretinography ,Humans ,Medicine ,Macula Lutea ,Bestrophins ,Best disease ,medicine.diagnostic_test ,business.industry ,Arden ratio ,Eye Diseases, Hereditary ,DNA ,General Medicine ,Electrooculography ,eye diseases ,Phenotype ,030104 developmental biology ,Intracellular calcium homeostasis ,Mutation ,030221 ophthalmology & optometry ,Female ,sense organs ,business ,Autosomal recessive bestrophinopathy - Abstract
Purpose To evaluate the electrooculogram (EOG) in a large series of patients with Best disease and autosomal recessive bestrophinopathy. Methods A retrospective review of consecutive cases at Moorfields Eye Hospital, London, United Kingdom. Patients with Best disease or autosomal recessive bestrophinopathy who, after electrophysiologic testing, had a normal or atypical EOG light rise were identified. Main outcome measure was EOG amplitude, clinical phenotype and genotype. Results One hundred thirteen patients were identified with likely disease-causing sequence variants in BEST1 (99 Best disease and 14 autosomal recessive bestrophinopathy). Electrooculograms had been performed in 75 patients. Twenty patients (27%) had no detectable light rise (Arden ratio of 100%) and 49 (65%) had Arden ratios of between 100% to 165%. Six patients (8%) were found to have an EOG light rise of >165%. No cases demonstrated significant interocular asymmetry in EOG amplitude. Conclusion The current work provides significant clinical evidence that the EOG phenotype in Best disease and autosomal recessive bestrophinopathy is more variable than currently appreciated. As a normal EOG may occur in the presence of a classical fundus appearance, the consequences of BEST1 mutation may be independently expressed, possibly mediated through differential effects on intracellular calcium homeostasis.
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- 2018
9. ISCEV standard for clinical electro-oculography (2010 update).
- Author
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Marmor, Michael F., Brigell, Mitchell G., McCulloch, Daphne L., Westall, Carol A., and Bach, Michael
- Abstract
The clinical electro-oculogram (EOG) is an electrophysiological test of function of the outer retina and retinal pigment epithelium (RPE) in which changes in electrical potential across the RPE are recorded during successive periods of dark and light adaptation. This document presents the 2010 EOG Standard from the International Society for Clinical Electrophysiology of Vision (ISCEV: ). This revision has been reorganized and updated, but without changes to the testing protocol from the previous version published in 2006. It describes methods for recording the EOG in clinical applications and gives detailed guidance on technical requirements, practical issues, and reporting of results. It is intended to promote consistent quality of testing and reporting within and between clinical centers. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
10. Mutation Analysis of the VMD2 Gene in Thai Families with Best Macular Dystrophy.
- Author
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Atchaneeyasakul, La-ongsri, Jinda, Worapoj, Sakolsatayadorn, Natta, Trinavarat, Adisak, Ruangvoravate, Ngamkae, Thanasombatskul, Nualanong, Thongnoppakhun, Wanna, and Limwongse, Chanin
- Subjects
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RETINAL degeneration , *GENETIC mutation , *DYSTROPHY , *EXONS (Genetics) , *NUCLEIC acids - Abstract
Background: To identify genetic mutations of the VMD2 gene in two Thai families with Best macular dystrophy. Materials and Methods: Ophthalmic examination including best-corrected visual acuity (BCVA), dilated fundus examination and fundus photography, and electro-oculography (EOG) was performed in two probands and their family members. Mutation screening of the VMD2 gene was performed by single-strand conformation polymorphism (SSCP) analysis followed by direct DNA sequencing of the abnormal exons. Results: The 58-year-old male proband demonstrated typical egg yolk-like macular lesion in both eyes. Mutational screening of VMD2 identified a band shift in exon 7, which was confirmed by direct DNA sequencing to be a G to A transition at position 724 bp. This novel missense mutation resulted in the change of an amino acid valine to methionine and was responsible for the abnormal Arden ratio in the proband's daughter. The second male proband age 25 had a characteristic egg yolk-like macular lesion in the left eye and a scrambled egg appearance in the right. Mutation analysis identified a C to T transition at position 652 bp in exon 6. This reported missense mutation led to an amino acid substitution of cysteine for arginine. The mutation was documented in the maternal grandmother, the mother, as well as the elder sister of the proband. Conclusions: The Val-242-Met mutation is associated with a late-onset visual disturbance and the Arg-218-Cys mutation was associated with marked intra-familial clinical variability of expression. Presymptomatic testing will be available to the family members at risk with high accuracy. [ABSTRACT FROM AUTHOR]
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- 2008
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11. ISCEV Standard for clinical electro-oculography (2017 update)
- Author
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Laura J. Frishman, Anthony G. Robson, Brett G. Jeffrey, Michael Bach, and Paul A Constable
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Retinal pigment epithelium (RPE) ,Eye Diseases ,Light ,genetic structures ,Computer science ,ISCEV Standards ,Light peak:dark trough ratio ,Retinal Pigment Epithelium ,Light adaptation ,03 medical and health sciences ,0302 clinical medicine ,Fast oscillation (FO) ,Arden ratio ,Physiology (medical) ,medicine ,Saccades ,Humans ,Vision, Ocular ,Protocol (science) ,Clinical electrophysiology ,Electro-oculogram (EOG) ,medicine.diagnostic_test ,Adaptation, Ocular ,Electrooculography ,Electro-oculography ,Sensory Systems ,eye diseases ,Electrophysiology ,Ophthalmology ,030221 ophthalmology & optometry ,Optometry ,sense organs ,Erratum ,030217 neurology & neurosurgery - Abstract
The clinical electro-oculogram (EOG) is an electrophysiological test of the outer retina and retinal pigment epithelium (RPE) in which changes in the electrical potential across the RPE are recorded during successive periods of dark and light adaptation. This document presents the 2017 EOG Standard from the International Society for Clinical Electrophysiology of Vision (ISCEV: www.iscev.org). This standard has been reorganized and updated to include an explanation of the mechanism of the EOG, but without substantive changes to the testing protocol from the previous version published in 2011. It describes methods for recording the EOG in clinical applications and gives detailed guidance on technical requirements, practical issues and reporting of results with the main clinical measure (the Arden ratio) now termed the light peak:dark trough ratio. The standard is intended to promote consistent quality of testing and reporting within and between clinical centers.
- Published
- 2017
12. The influence of iris color and retina pigment epithelium melanin on allergic rhinitis
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Tuncay Küsbeci, Faruk Öztürk, Güliz Fatma Yavaş, Fethullah Kenar, Sefa Dereköy, and Abdullah Ayçiçek
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Retina ,Pathology ,medicine.medical_specialty ,Allergy ,business.industry ,medicine.disease ,Epithelium ,melanin ,Iris color ,Melanin ,Pigment ,medicine.anatomical_structure ,Facial plastic surgery ,visual_art ,Ophthalmology ,Allergic rhinitis ,iris color ,retina pigment epithelium ,Arden ratio ,visual_art.visual_art_medium ,Medicine ,business - Abstract
Objective: The purpose of this case control study is to establish the influence of iris color and retina pigment epithelium melanin on allergic rhinitis., Methods: Ninety-nine subjects diagnosed prospectively as allergic rhinitis and 85 control subjects were included in the study. Color of iris was recorded after ophthalmic examination. Electro-oculographic measurement was done after pupil dilatation and Arden ratios were recorded., Results: Mean age was 29.44 +/- 9.8 years in subject with allergic rhinitis and 32.67 +/- 12.9 years in control subjects (p>0.05). Measured mean Arden ratio was 158.22 +/- 29.4 in subjects with allergic rhinitis and 179.34 +/- 29.3 in normal subjects (p, Conclusion: An association between allergic rhinitis and melanin content of iris and retina pigment epithelium was found. It can be speculated that pigment-producing system may play a role in the pathogenesis of the allergic rhinitis.
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- 2016
13. Best abstract award runner-up. Effect of acute optic neuropathies on Light Peak: Dark trough ratio (Arden ratio) of electro-oculography
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D. Baminiwatta, L.P.M.M.K. Pathirage, Vajira S. Weerasinghe, R.G.L. shiroma, Saman Senanayake, D.W.P. Dahanayake, and A. Hangilipola
- Subjects
Optics ,Materials science ,Neurology ,Thunderbolt ,business.industry ,Physiology (medical) ,Arden ratio ,Trough (geology) ,Neurology (clinical) ,Electro-oculography ,business ,Sensory Systems - Published
- 2019
14. İris rengi ve retina pigment epitel melanininin alerjik rinite olan etkisi
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DEREKÖY, Sefa, KENAR, Fethullah, YAVAŞ, Güliz Fatma, KÜSBECİ, Tuncay, ÖZTÜRK, Faruk, and AYÇİÇEK, Abdullah
- Subjects
genetic structures ,Health Care Sciences and Services ,Allergic rhinitis ,iris color ,retina pigment epithelium ,Arden ratio ,sense organs ,Allergic rhinitis,iris color,retina pigment epithelium,Arden ratio,melanin ,Sağlık Bilimleri ve Hizmetleri ,melanin - Abstract
Objective: The purpose of this case control study is to establish the influence of iris color and retina pigment epithelium melanin on allergic rhinitis.Methods: Ninety-nine subjects diagnosed prospectively as allergic rhinitis and 85 control subjects were included in the study. Color of iris was recorded after ophthalmic examination. Electro-oculographic measurement was done after pupil dilatation and Arden ratios were recorded.Results: Mean age was 29.44±9.8 years in subject with allergic rhinitis and 32.67±12.9 years in control subjects (p>0.05). Measured mean Arden ratio was 158.22±29.4 in subjects with allergic rhinitis and 179.34±29.3 in normal subjects (p
- Published
- 2016
15. Improvement of the Saccadic Eye Movements with the Sport Training Activity
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Ahmad Mursyid Ahmad Rudin and Maryam Nazihah Sharipan
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medicine.medical_specialty ,genetic structures ,Sport training ,Saccadic eye movement ,Significant difference ,Arden ratio ,Eye movement ,Audiology ,eye diseases ,Saccadic masking ,Fixation (visual) ,medicine ,sense organs ,Psychology ,Dark phase - Abstract
Saccadic eye movement is a short rapid and abrupt movement of the eye occurring in fixating from one point to another. The demand of eye movement in sport vision is crucial to locate visual targets and stabilize images on the retina. Athletes were reported to have better visual abilities than non-athletes. In this study, athletes who actively played badminton (n = 20) and non-badminton players (n = 20) aged between 12 and 18 years old were recruited. Electro-oculography (EOG) was employed for analysis of saccadic eye movements. The clinical EOG made indirect measurement to record the eye movement with EOG angle of 30o. Subjects were instructed to follow the alternated light fixation without turning head during the saccadic task. The system automatically measured the average result of Arden ratio, latency, and amplitude potentials in dark phase and light phase of saccadic eye movement with both dark and light stages plotted and curve fitted. No significant differences (p = 0.20) were found between badminton player and non-badminton player in the mean latency of saccadic eye movements with 19.25 ± 0.83 and 18.79 ± 1.35 ms, respectively. Meanwhile, the badminton player showed statistically significant difference in amplitude of saccadic eye movements than non-badminton player (p < 0.001). The mean amplitude of saccadic eye movements in badminton player and non-badminton player was 28.34 ± 8.04 and 19.51 ± 5.61 µV, respectively. The saccadic eye movement showed how fast the visual system can fixate on an object. Improvement in the component in saccadic eye movements indicated that training activities might be contributed to the superiority of vision skills in badminton player.
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- 2015
16. NORMAL VALUES IN CLINICAL ELECTROOCULOGRAPHY
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Erik Krogh
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Adult ,Male ,Refractive error ,medicine.medical_specialty ,Adolescent ,genetic structures ,Iris ,Dark Adaptation ,Normal values ,Refraction, Ocular ,Correlation ,Sex Factors ,Reference Values ,Ophthalmology ,medicine ,Humans ,Ocular Physiological Phenomena ,Aged ,Mathematics ,medicine.diagnostic_test ,Pigmentation ,Age Factors ,Arden ratio ,Pupil ,General Medicine ,Electrooculography ,Middle Aged ,medicine.disease ,eye diseases ,Dark-adapted ,Female ,Interpupillary distance ,sense organs ,Dimensionless quantity - Abstract
Two EOG parameters - The Arden ratio (A) and an expression devised by Gliem (G) - from a sample of normal human subjects are studied. Their relations to the EOG potential and time parameters and to sex, age, pupillary diameter, degree of iris pigmentation, refractive error and axial length, ocular protrusion and interpupillary distance were assessed. Right eye and left eye distributions were congruent, although individual differences were sometimes appreciable, especially in the case of G. The two ratios were positively correlated and both showed a negative correlation to the interval between the dark trough and the light peak. Correlations to the EOG potential parameters, especially the light induced potential rise of the dark adapted eye, were also established. In the case of A, a higher level was disclosed in the male half of the sample. A negative age correlation, predominant in the female part of the sample, characterized both ratios. The two ratios were positively correlated to the pupil diameter, negatively correlated to the degree of refractive errror, and positively correlated to the degree of ocular protrusion. The consequences for the clinical EOG test are discussed, and it is concluded that the present EOG procedure is a qualitative rather than a quantitative test.
- Published
- 2009
17. Comparing Short-Duration Electro-Oculograms with and without Mydriasis in Healthy Subjects
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C. Turksever, Margarita G. Todorova, and Selim Orgül
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Miosis ,Adult ,Male ,medicine.medical_specialty ,Mydriatics ,Adolescent ,Sensitivity and Specificity ,Retina ,Young Adult ,Age groups ,Reference Values ,Ophthalmology ,medicine ,Mydriasis ,Humans ,Short duration ,business.industry ,Arden ratio ,Healthy subjects ,Reproducibility of Results ,Middle Aged ,Surgery ,Electrooculography ,Female ,medicine.symptom ,business ,Dark phase - Abstract
Background: In order to obtain artifact-free electro-oculogram recordings the subjectʼs cooperation is necessary. The aim of our study is to evaluate the recording characteristics of short-duration EOG and to compare the effect of mydriasis on electro-oculogram recordings in a cohort of controls. Patients and Methods: Electro-oculogram recordings were performed on a light-emitting diode stimulus screen using a RETI-port gamma plus 2 system (RETIscan™, Roland Consult). Fast oscillations were set at 1.5 sec (6 cycles; total duration 75 sec).The dark phase included: pre-adaptation (6 min), alternate fixation (4 min), fixation-rest (20 sec), 100 sweeps. The light phase included: light adaptation (4 min), alternate fixation (10 min), fixation-rest (20 sec), 250 sweeps. The amplifier band pass was filtered at 0.1 ÷ 50 Hz. The background illumination in mydriasis was 100 cd/m 2 and in miosis – 450 cd/m 2 . Results: A total of 55 controls participated and were divided into three age groups [number; mean (years, y); ± SD]: group 1: 18–20 years (19; 19.49 years; ± 0.89); group 2: 20–40 years (18; 27.91 years; ± 5.39) and group 3: 40–60 years (18; 48.66 years; ± 4.00). The Arden ratio, dark-trough and light-peak did not differ between recordings with or without mydriasis (p = 0.914; p = 0.880; p = 0.680, linear mixed-effects model). The age did not influence the Arden ratio, dark-trough, light-peak (p = 0.206; p = 0.112; p = 0.155). Arden ratio, dark-trough, light-peak were comparable between tested eyes (p = 0.934; p = 0.193; p = 0.270). Conclusions: Short-duration electro-oculograms allow successful recording, furthermore, the application of mydriasis does not influence the quality of the recording.
- Published
- 2015
18. Surveillance électrophysiologique des patients épileptiques traités par Vigabatrin
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M. Baulac, J.-P. Nordmann, and M.-H. Rigolet
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Pediatrics ,medicine.medical_specialty ,genetic structures ,medicine.diagnostic_test ,business.industry ,Visual impairment ,Arden ratio ,Retrospective cohort study ,Electrooculography ,medicine.disease ,eye diseases ,Vigabatrin ,Visual field ,Surgery ,Central nervous system disease ,Ophthalmology ,Epilepsy ,medicine ,medicine.symptom ,business ,medicine.drug - Abstract
Vigabatrin is a GABA mimetic antiepileptic agent that has been used for 10 years in cases of epilepsy that resist other treatments. Since 1997, concentric visual field defects have been reported. Before any visual symptom complaint, they quickly become irreversible and highly disabling. To prevent this visual impairment, the monitoring protocol must be defined with reliable and well-supported tests, so that patients treated with Vigabatrin can be regularly monitored. Our purpose was to know if EOG impairments were frequent, if their severity was proportional to visual impairment, and if the Arden ratio could be a predictive criterion of Vigabatrin toxicity. Seventy-two patients treated with Vigabatrin for 2-10 years were examined, and EOG results were compared with a normal population EOG and then the patient's visual field. The monitoring protocol proposed includes EOG, which seems to be the most sensitive and specific diagnostic tool for screening Vigabatrin-treated patients.
- Published
- 2005
19. Toxic Retinopathy in Malaria Tropica
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Schmidt, Barbara, Henkes, H. E., editor, François, Jules, editor, De Rouck, A., editor, Pearlman, J. T., editor, and Kelsey, J., editor
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- 1978
- Full Text
- View/download PDF
20. Normative values for electro-oculography in adults
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Juliana Simões Munhoz, Adriana Berezovsky, Paula Yuri Sacai, and Solange Rios Salomão
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medicine.medical_specialty ,Epitélio pigmentado ocular ,Posterior pole ,Valores de referência ,Retina ,Reference values ,Optics ,lcsh:Ophthalmology ,Ophthalmology ,medicine ,Pigment epithelium of eye ,Scotopic vision ,medicine.diagnostic_test ,business.industry ,Eletro-oculografia ,Arden ratio ,General Medicine ,Electrooculography ,RE1-994 ,Saccadic masking ,Electrophysiology ,Amplitude ,Eletrofisiologia ,lcsh:RE1-994 ,Standard protocol ,business ,Photopic vision - Abstract
OBJETIVO: Estabelecer valores normativos para o eletro-oculografia (EOG), em grupo de voluntários normais, segundo o protocolo recomendado pela Sociedade Internacional de Eletrofisiologia Visual Clínica (ISCEV). MÉTODO: Participaram 34 sujeitos com idades de 18 a 55 anos (média 26,75 ± 10,50), 9 homens e 24 mulheres. O EOG foi realizado utilizando eletrodos e estímulos luminosos. A tarefa do sujeito foi fixar estímulos luminosos (LEDs) em frente ou realizando movimentos sacádicos horizontais. O exame constou de três fases: 1- Pré-adaptação; 2- Escotópica e 3- Fotópica. O índice de Arden foi determinado como sendo a proporção entre o pico máximo da amplitude na fase fotópica, dividido pelo vale máximo da amplitude na fase escotópica. RESULTADO: Na fase escotópica, o vale máximo ocorreu entre 14 e 21 minutos após o início do exame (média 17,82 ± 2,11 minutos) e a amplitude variou de 206 a 635 µV (média 365,73 ± 122,52 µV). Na fase fotópica, o pico máximo ocorreu entre 27 a 34 minutos (média 30,06 ± 1,80 minuto) e a amplitude variou de 646 a 1249,50µV (média 950,70 ± 179,16). O índice de Arden variou de 1,85 a 4,02 (média 2,79±0.63) sendo o limite inferior de 1,92 e o superior de 4,00. CONCLUSÃO: Os valores para o índice de Arden estão de acordo com valores descritos anteriormente na literatura, sendo o limite inferior de normalidade quando este for maior ou igual a 1,92 e serão úteis para avaliação de pacientes com distúrbios retinianos. A inclusão de outras faixas etárias fornecerá dados normativos mais abrangentes. PURPOSE: To determine normative values for EOG in a group of healthy adult volunteers, according to the standard protocol recommended by the International Society for Clinical Eletrophisiology of Vision - ISCEV. METHODS: 33 volunteers aging from 18 to 55 years (mean=26.75±10.50) were included in the study. EOG was recorded by skin electrodes positioned in the external canthi of the eyes, with LED stimulus presented in a Ganzfeld dome. Subject's task was to fix the LED stimulus either straight ahead or with saccadic horizontal movements. The potential difference between the cornea and posterior pole of the eye was recorded each minute. The examination was done in 3 phases: 1- pre-adaptation; 2- dark (scotopic) and 3- light (photopic). The Arden ratio was calculated as the proportion between the maximum peak amplitude in the light phase divided by the minimum peak amplitude in the dark. RESULTS: At the scotopic phase, the minimum peak amplitude occurred between 14 and 21 minutes after the beginning of the stimulation (mean=17.82±2.11 min) and the amplitude ranged from 206 to 635 µV (mean 365.73±122.52 µV). At the photopic phase the maximun peak amplitude occurred between 27 and 34 minutes (mean=30.06±1.80 min); the amplitude ranged from 646 to 1250 µV (mean= 950.70±179.16 µV). Arden ratio ranged from 1.85 to 4.02 with a lower normal limit of 1.92 and the upper limit of 4.00. CONCLUSION: The results obtained in this study are comparable to those previously reported in the literature, with a lower normal limit of 1.92 for Arden ratio. These values will be helpful to evaluate patients with several retinal disorders. Inclusion of other age groups will provide extended normative data.
- Published
- 2004
21. ISCEV Standard for Clinical Electro-oculography (EOG) 2006
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Brown, Malcolm, Marmor, Michael, Vaegan, Zrenner, Eberhard, Brigell, Mitchell, and Bach, Michael
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- 2006
- Full Text
- View/download PDF
22. Comparing short-duration electro-oculogram with and without mydriasis in controls
- Author
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M. G. Todorova, Cengiz Türksever, and Selim Orgül
- Subjects
Miosis ,medicine.medical_specialty ,business.industry ,Electro oculogram ,Arden ratio ,General Medicine ,Ophthalmology ,Optics ,medicine ,Mydriasis ,medicine.symptom ,Dark phase ,business ,Short duration - Abstract
Purpose In order to obtain artefact-free EOG recordings the subject’s cooperation is necessary. The aim of our study is to evaluate recording characteristics of the short-duration EOG and to compare the effect of mydriasis on EOG recordings in a cohort of controls. Methods EOG recordings were performed on a LED stimulus screen using a RETI-port gamma plus2 system (RETIscanTM, Roland Consult). Dark phase included: pre-adaptation (6min), alternate fixation (4min), fixation-rest (20sek), 100 sweeps. Light phase included: light adaptation (4min), alternate fixation (10min), fixation-rest (20sek), 250 sweeps. Amplifier was band pass filtered at 0.1-50Hz. Background illumination in mydriasis was 100cd/m2 and in miosis 450cd/m2. Fast oscillations were set at 1.5sek (6 cycles; total duration 75sek). Results A total of 55 controls divided in three age-groups participated (number; mean (years, y); ±SD): group 1: 18- 20y (19; 19.49y; ±0.89); group 2: 20-40y (18; 27.91y; ±5.39) and group 3: 40-60y (18; 48.66y; ±4.00). Arden ratio (AR), dark-trough (DT) and light-peak (LP) did not differ between recordings with or without mydriasis (p=0.885; p=0.860; p=0.776, linear mixed-effects model). Age did not influence the AR, DT, LP (p= 0.206; p=0.112; p=0.155). AR, DT, LP were comparable between eyes tested (p=0.998; p=0.196; p=0.324). Conclusion Short-duration EOG allows successful recording, where the application of mydriasis does not influence the quality of the recording.
- Published
- 2014
23. Clinical characteristics of 14 Japanese patients with X-linked juvenile retinoschisis associated with XLRS1 mutation
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Susumu Ishida, Kei Shinoda, Yoshihisa Oguchi, and Yukihiko Mashima
- Subjects
Adult ,Male ,medicine.medical_specialty ,X Chromosome ,Visual acuity ,Adolescent ,Genotype ,genetic structures ,Fundus Oculi ,Genetic Linkage ,Peripheral retinoschisis ,Visual Acuity ,Gene mutation ,medicine.disease_cause ,Retina ,Japan ,Ophthalmology ,Electroretinography ,medicine ,Humans ,Child ,Eye Proteins ,Genetics (clinical) ,Retrospective Studies ,Mutation ,medicine.diagnostic_test ,business.industry ,Retinal Degeneration ,Arden ratio ,Infant ,eye diseases ,Blotting, Southern ,Phenotype ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,sense organs ,Juvenile retinoschisis ,medicine.symptom ,business ,Erg - Abstract
To characterize the clinical features associated with XLRS1 gene mutations in Japanese patients with X-linked juvenile retinoschisis (xlRS), we evaluated the following data on 14 Japanese males from 13 unrelated families with XLRS1 mutations: age and symptoms at first visit to an ophthalmologist and ophthalmologic findings including visual acuity, refractive errors, fundoscopic appearance, and results of electroretinography (ERG) and electro-oculography (EOG). Each clinical finding was reviewed when the patients were between six and eight years of age. The best-corrected visual acuity in 12 patients (24 eyes) between the ages 6 and 8 years ranged from 1.0 to no light perception. Macular abnormalities were present in all cases. Peripheral retinoschisis was present in 14 of 26 eyes (53.8%). In the 21 eyes for which a single-flash ERG had been recorded, b-wave amplitude was reduced in 17 eyes. The EOG showed a low Arden ratio in three of the 13 eyes in the seven patients evaluated. No clear relationship was observed between the clinical features and the existing mutations. Three of four patients with a visual acuity less than 0.1 had retinal detachment or severe macular lesion that had occurred before the age of four years. Two patients harbored deletions of exon 1 or of the boundary region between exon 3 and intron 3, and one patient harbored R182C in exon 6. The present study shows a heterogeneity of mutations in the XLRS1 gene and phenotypic variations in 14 Japanese patients with xlRS.
- Published
- 2000
24. The electrooculogram.
- Author
-
Creel DJ
- Subjects
- Electrooculography instrumentation, Humans, Retina physiopathology, Visual Acuity physiology, Vitelliform Macular Dystrophy physiopathology, Electrooculography methods, Retina diagnostic imaging, Retina physiology, Vitelliform Macular Dystrophy diagnostic imaging
- Abstract
The electrooculogram (EOG) measures the cornea-positive standing potential relative to the back of the eye. By attaching skin electrodes outside the eye near the lateral and medial canthus, the potential can be measured by having the patient move the eyes horizontally a set distance. The voltage becomes smaller in the dark, reaching its lowest potential after 8-12min, the so-called dark trough. When the lights are turned on, the potential rises, reaching a peak by about 10min. When the size of the light peak is compared to the dark trough, the normal ratio should be near 2:1. A light peak:dark trough ratio of less than 1.7 is considered abnormal. The origin of electrooculographic potentials is the pigment epithelium of the retina interacting with the midretina. The light rise of the potential requires both a normal pigment epithelium and normal midretinal function. The most common use of the electrooculogram is to confirm Best disease. Best disease is identified by the appearance of an egg-yellow fundus and can be confirmed by recording both an electroretinogram (ERG) and electrooculogram (EOG). The ERG will be normal and the EOG will be abnormal. The EOG is also used for tracking eye movement., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
25. Giant macular hole with Best's disease in a young boy
- Author
-
Souvik Mandal and Soumyava Basu
- Subjects
Male ,medicine.medical_specialty ,Best's disease ,genetic structures ,Visual Acuity ,Fundus (eye) ,Retina ,Lipofuscin ,Diagnosis, Differential ,Optical coherence tomography ,Ophthalmology ,medicine ,Humans ,Child ,Macular hole ,Retinal pigment epithelium ,medicine.diagnostic_test ,business.industry ,Arden ratio ,medicine.disease ,Retinal Perforations ,eye diseases ,Vitelliform Macular Dystrophy ,medicine.anatomical_structure ,Optometry ,sense organs ,business ,Tomography, Optical Coherence - Abstract
An eight-year-old boy presented with decreased near and distance vision in both eyes. The right ocular fundus showed a giant macular hole surrounded by a vitelliform ring. Spectral domain optical coherence tomography (SD-OCT) revealed a full-thickness macular hole with cystic spaces at the edges. The left fundus had an egg-yolk like appearance of 1.5-disc diameter at the macular region. SD-OCT showed an optically empty space between retinal pigment epithelium and the neurosensory retina. Fundus autofluorescence confirmed the presence of lipofuscin in both eyes. The Arden ratio was 1.38 for the right eye and 1.61 for the left. There was no surgical intervention because of the poor prognosis due to large size of the hole. Environmental modification and contrast-enhancing measures were explained to the patient and his parents.
- Published
- 2012
26. ISCEV standard for clinical electro-oculography (2010 update)
- Author
-
Carol A. Westall, Michael Bach, Daphne L. McCulloch, Michael F. Marmor, and Mitchell Brigell
- Subjects
Internationality ,Time Factors ,genetic structures ,Electro oculogram ,Dark Adaptation ,Retinal Pigment Epithelium ,Biology ,Retina ,Ocular physiology ,Physiology (medical) ,Oscillometry ,Saccades ,Humans ,Patient compliance ,Reference standards ,Electrodes ,Societies, Medical ,Vision, Ocular ,Protocol (science) ,Adaptation, Ocular ,Arden ratio ,Electro-oculography ,Reference Standards ,eye diseases ,Sensory Systems ,Electrophysiology ,Ophthalmology ,Electrooculography ,Clinical electrophysiology ,Optometry ,Patient Compliance ,sense organs ,Photic Stimulation - Abstract
The clinical electro-oculogram (EOG) is an electrophysiological test of function of the outer retina and retinal pigment epithelium (RPE) in which changes in electrical potential across the RPE are recorded during successive periods of dark and light adaptation. This document presents the 2010 EOG Standard from the International Society for Clinical Electrophysiology of Vision (ISCEV: www.iscev.org ). This revision has been reorganized and updated, but without changes to the testing protocol from the previous version published in 2006. It describes methods for recording the EOG in clinical applications and gives detailed guidance on technical requirements, practical issues, and reporting of results. It is intended to promote consistent quality of testing and reporting within and between clinical centers.
- Published
- 2011
27. Studies on the stability of the clinical electro-oculogram
- Author
-
Nathaniel Timmins and Michael F. Marmor
- Subjects
Adult ,Male ,medicine.medical_specialty ,Light ,genetic structures ,Electrodiagnosis ,Electro oculogram ,Dark Adaptation ,Biology ,Pupil ,Standard deviation ,Optics ,Physiology (medical) ,Ophthalmology ,medicine ,Pupillary response ,Humans ,Circadian rhythm ,Pigment Epithelium of Eye ,medicine.diagnostic_test ,business.industry ,Arden ratio ,Electrooculography ,Reference Standards ,Sensory Systems ,Circadian Rhythm ,Female ,sense organs ,business - Abstract
The electro-oculogram is variable as a clinical test, but the recording technique has not been standardized, and differences in the protocols for adaptation and stimulation among laboratories may contribute to the variability. To analyze some of these factors, we performed more than 100 electro-oculograms on a single subject under different conditions. Both the Arden ratio and the ratio of light peak amplitude to a stable dark-adapted baseline were independent of pupillary dilation but linearly related to retinal illumination measured in trolands. Between 3.0 and 4.0 log trolands, the values began to level off, but they were difficult to interpret because of subject discomfort above 3.5 log trolands. The Arden ratios were influenced by preadaptation light levels and were roughly 20% higher above 90 cd/m2 than below 45 cd/m2. There was a circadian rhythm in dark trough, baseline and light peak values, but the composite Arden ratio and light peak/baseline ratio showed little circadian effect. The light peak/baseline ratios were slightly more stable than the Arden ratios; the variability (defined as [standard deviation x 100]/mean) was 6.6% and 12.5%, respectively. Our results suggest that stimulus intensities for clinical electro-oculographic testing should be between 3.0 and 3.5 log trolands; pupil dilation is optional. This translates into light levels of 141-447 cd/m2 for a 3-mm pupil and 20-63 cd/m2 for an 8-mm pupil. The reduction in variability and independence from preadaptation achieved by using the light peak/baseline ratio instead of the Arden ratio must be weighed against the time required to achieve a stable dark baseline.
- Published
- 1992
28. Early hydroxychloroquine retinal toxicity enhanced by laser flare-cell meter
- Author
-
Pietro Leonetti, Mauro Cellini, Emilio C. Campos, G. O. Bravetti, Bravetti G.O., Leonetti P, Cellini M, and Campos E.C.
- Subjects
Pathology ,medicine.medical_specialty ,Retina ,Retinal pigment epithelium ,business.industry ,Cell ,Arden ratio ,Hydroxychloroquine ,General Medicine ,medicine.disease ,Ophthalmology ,medicine.anatomical_structure ,Retinal toxicity ,Rheumatoid arthritis ,Toxicity ,medicine ,business ,medicine.drug - Abstract
Purpose The aim of this study is the evaluation of the electro-oculogram (EOG) against the laser flare-cell meter methodology (LFM) in early detection of hydroxychloroquine retinal toxicity. Several studies have showed that hydroxychloroquine, an antiprotozoal drug used in the treatment of malaria and various rheumatic diseases, can cause severe visual loss due to a toxic effect on the outer retina and the retinal pigment epithelium (EPR). Methods We enrolled 12 patients (3 males and 9 females) with rheumatoid arthritis (10 patients) and systemic lupus erythematosus (2 patients) in therapy with hydroxychloroquine without retinal toxicity, and 12 health controls (5 males and 7 females). EOG and LFM with a laser flare-cell meter instruments (FM-500, Kowa, Tokio, Japan).were performed in all patients and in health controls. The Student’s t test and the Bartlett’s correlation test was performed to compare the results of EOG and LFM with the hydroxychloroquine dose considering significant a p
- Published
- 2008
29. Choroideremia carriers maintain a normal electro-oculogram (EOG)
- Author
-
Kerry E. McTaggart, Ian M. MacDonald, Christina Sereda, Ryan J. Yau, and Yves Sauve
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,Heterozygote ,Visual acuity ,genetic structures ,Eye disease ,Electro oculogram ,DNA Mutational Analysis ,Visual Acuity ,Fundus (eye) ,Biology ,Polymerase Chain Reaction ,Choroideremia ,Retina ,Physiology (medical) ,medicine ,Humans ,Pigment Epithelium of Eye ,Adaptor Proteins, Signal Transducing ,Retinal pigment epithelium ,Arden ratio ,Middle Aged ,medicine.disease ,eye diseases ,Sensory Systems ,Ophthalmology ,Electrooculography ,medicine.anatomical_structure ,rab GTP-Binding Proteins ,Mutation ,Female ,sense organs ,medicine.symptom - Abstract
To assess the functional integrity of the retinal pigment epithelium and outer retina in choroideremia (CHM) carriers with confirmed mutations in the REP-1 gene, by recording the EOG. The visual function of 17 choroideremia carriers ages 25–61 was assessed by determining their Snellen visual acuity and by recording the Arden ratio of the EOG. The 15 exons of the CHM gene were PCR-amplified from DNA from each of the carriers and their sequences were compared to the normal sequence to identify mutations. The 17 CHM carriers had normal logMAR visual acuity (average of 0.07: Snellen equivalent of 20/25; with no acuities lower than 20/40). The average of the Arden ratio recorded from the 17 carriers was 2.71, which is not significantly different from the average value of 2.46 recorded in our lab. Fundus examination revealed mottled areas of chorioretinal degeneration consistent with the carrier status of CHM. Mutations in the CHM gene were identified in all CHM carriers by sequencing. Whereas clinical observation suggests that progressive fundus changes are present in female carriers, these carriers do not show a change in the Arden ratio of the EOG over the ages studied (25–61 years).
- Published
- 2006
30. Diagnosis of the macular diseases from pattern electroretinography signals using artificial neural networks
- Author
-
Sadık Kara and Ayşegül Güven
- Subjects
Artificial neural network ,Computer science ,business.industry ,General Engineering ,Arden ratio ,Feed forward ,Macular disease ,Pattern electroretinography ,Machine learning ,computer.software_genre ,Backpropagation ,Computer Science Applications ,Artificial Intelligence ,Sensitivity (control systems) ,Artificial intelligence ,business ,computer - Abstract
In this paper, we purpose a diagnostic procedure to identify the macular disease from pattern electroretionography (PERG) signals using artificial neural networks (ANN) methods. Multilayer feed forward ANN trained with a Levenberg Marquart backpropagation algorithm was implemented. The designed classification structure has about 96% sensitivity, 100% specifity and correct classification is calculated to be 98%. The end results are classified as Healthy and Diseased. Testing results were found to be compliant with the expected results that are derived from the physician's direct diagnosis, angiography and Arden ratio of electrooculogram (EOG). The stated results show that the proposed method could point out the ability of design of a new intelligent assistance diagnosis system. (c) 2005 Elsevier Ltd. All rights reserved.
- Published
- 2006
31. Short communication
- Author
-
Rogers Gl, Mary Lou McGregor, Pappa Ks, L.E. Leguire, and Bremer Dl
- Subjects
Vitamin ,medicine.medical_specialty ,genetic structures ,Abnormal EOG ,business.industry ,Electro oculogram ,Arden ratio ,medicine.disease ,Gastroenterology ,Cystic fibrosis ,eye diseases ,Vitamin A deficiency ,Ophthalmology ,chemistry.chemical_compound ,chemistry ,Internal medicine ,Pediatrics, Perinatology and Child Health ,Medicine ,sense organs ,business ,Genetics (clinical) - Abstract
Electro-oculograms (EOGs) were recorded in a patient with cystic fibrosis and vitamin A deficiency before and during vitamin A supplementation (25,000 IU/day). Before vitamin A supplementation the EOG Arden light/dark ratio was 1.27. After seven months of vitamin A supplementation the Arden ratio increased to 3.0. These results reveal that vitamin A deficiency can cause an abnormal EOG.
- Published
- 1992
32. Employment of electrofunctional tests in the differential diagnosis of central vein occlusion
- Author
-
A. P. Tormene, F. Moro, and S. Fabris
- Subjects
medicine.medical_specialty ,Oscillatory potentials ,business.industry ,Arden ratio ,medicine.disease ,eye diseases ,Vein occlusion ,Ophthalmology ,Central retinal vein occlusion ,Anesthesia ,medicine ,CRVO - Central retinal vein occlusion ,Differential diagnosis ,business - Abstract
The authors recorded electrofunctional tests (electroretinogram, oscillatory potentials and electrooculogram) in 33 patients suffering from recent central retinal vein occlusion (CRVO). Among these different tests, OP oscillatory index, Arden ratio and implicit time of b-wave were considered useful to recognize ischaemic CRVO.
- Published
- 1991
33. Electro-oculography in pigment dispersion syndrome
- Author
-
Luciano Cerulli, M.J. Galasso, Federico Ricci, Carlo Nucci, and Gianluca Scuderi
- Subjects
Adult ,Male ,medicine.medical_specialty ,Electro-oculography ,Glaucoma ,Pigment dispersion syndrome ,Retinal pigment epithelium ,Ophthalmology ,Biology ,Exfoliation Syndrome ,Cellular and Molecular Neuroscience ,medicine ,Humans ,Iris (anatomy) ,Pigment Epithelium of Eye ,Analysis of Variance ,Settore MED/30 - Malattie Apparato Visivo ,Arden ratio ,food and beverages ,Electrooculography ,Glaucoma, Open-Angle ,Follow-Up Studies ,Chronic Disease ,Refractive Errors ,Female ,General Medicine ,medicine.disease ,Sensory Systems ,Epithelium ,medicine.anatomical_structure ,Open-Angle ,sense organs - Abstract
Clinical data and the common embryological origin of the pigment epithelium of the iris and retinal pigment epithelium suggest that the latter may be involved in the pigment dispersion syndrome (PDS). In our study functional changes of the retinal pigment epithelium were evaluated by electro-oculography in 10 PDS patients, 10 patients with chronic open-angle glaucoma (COAG) and 10 normal subjects. The mean dark-trough latency and Arden ratio for the PDS group were significantly lower than those of the COAG and control groups. Analysis of the Arden ratios based on the Kruskall-Wallis test revealed that 30% of the PDS values were subnormal with respect to the control group mean –1 SD. These results indicate primary involvement of the retinal pigment epithelium in PDS.
- Published
- 1998
34. Comparison of electro-oculogram recording methods
- Author
-
Viktor Scheiber, M. R. Lessel, A. Thaler, and P. Heilig
- Subjects
Male ,Electrodiagnosis ,Light ,Electro oculogram ,Dark Adaptation ,Pupil ,Retina ,Cellular and Molecular Neuroscience ,Tropicamide ,Optics ,medicine ,Humans ,Physics ,medicine.diagnostic_test ,business.industry ,Arden ratio ,General Medicine ,Electrooculography ,Middle Aged ,Sensory Systems ,Ophthalmology ,Amplitude ,business ,medicine.drug - Abstract
The purpose of this study was to compare the variability of the amplitude ratios and latencies of the electro-oculogram (EOG) light peak (LP) in three different recording conditions: Arden ratio (dark trough (DT): 12 min), modified Arden ratio (DT: 15 min) and light peak/dark baseline ratio (LP/BL: 35 min of dark adaptation). Additionally, EOGs from eyes with dilated and undilated pupils were recorded. The light intensity stimulating the eyes with dilated pupils was attenuated 1 log unit. The EOG amplitude ratios displayed no significant difference between the three conditions tested. The comparison of implicit times (time from onset of light exposure to LP) revealed significantly (p0.001) shorter values when the recording of the LP was preceded by a dark adaptation of 35 min. The broadening of the curves in DT/LP recordings might be caused by a superposition of a residual dark oscillation on the LP. The recordings from eyes with dilated pupils--stimulated with 1 log unit lower intensity--revealed lower amplitude ratios than the recordings from eyes with undilated pupils.
- Published
- 1993
35. Electro-oculography in autosomal dominant vitreoretinochoroidopathy
- Author
-
Michael F. Lewandowski and Dennis P. Han
- Subjects
Adult ,Male ,genetic structures ,Eye Diseases ,Light ,Fundus Oculi ,Dark Adaptation ,Biology ,Autosomal dominant vitreoretinochoroidopathy ,Retinal Diseases ,Electroretinography ,Humans ,Fluorescein Angiography ,Dominance (genetics) ,Genetics ,Arden ratio ,Electro-oculography ,Choroid Diseases ,Middle Aged ,Pedigree ,Vitreous Body ,Ophthalmology ,Electrooculography ,Female ,sense organs ,Retinitis Pigmentosa - Abstract
Thirteen members of a family presumed to be harboring the gene for autosomal dominant vitreoretinochoroidopathy were examined. In four affected members, electro-oculography demonstrated marked reduction of the Arden ratio (range, 1.1 to 1.5; normal,or = 1.8), despite electroretinographic evidence of mildly affected rod function and normal cone function. These findings suggested that a diffuse disturbance of the photoreceptor-pigment epithelium complex may have been present prior to wide-spread loss of photoreceptor function in the affected members of this family. As in previously described families, the pattern of inheritance appeared consistent with autosomal dominance.
- Published
- 1992
36. Computer-assisted analysis of the electro-oculogram
- Author
-
William R. Barry, Ian Favilla, Andrew D. Gosbell, and Guy Burkitt
- Subjects
genetic structures ,Computer science ,business.industry ,Electro oculogram ,Spectral properties ,Arden ratio ,Reproducibility of Results ,Pattern recognition ,Dark Adaptation ,eye diseases ,Retina ,Ophthalmology ,Electrooculography ,McNemar's test ,Chart ,Humans ,False Positive Reactions ,sense organs ,False positive rate ,Artificial intelligence ,Diagnosis, Computer-Assisted ,Abnormal results ,business - Abstract
A method of acquiring and analysing electro-oculogram signals was developed using computer-aided techniques. The repetitive nature, characteristic shape and spectral properties of the electro-oculogram are used in the automated analysis, enabling the retinal resting potential to be investigated. Online computer-aided automatic analysis of the electro-oculogram is efficient, reliable and accurate. Automated analysis produced results that have a highly significant degree of correlation (P less than 0.001) with the results obtained manually from strip chart recording of the electro-oculogram signals. The increased accuracy of the automatic analysis system demonstrates a significantly reduced (McNemar's Test) false positive rate in classifying abnormal results on the basis of Arden ratio. The computer-aided analysis system offers a useful clinical means of measuring the electro-oculogram for diagnostic and research purposes.
- Published
- 1991
37. The electrooculogram: A refinement of the method
- Author
-
H. Spekreijse, F. C. C. Riemslag, and H. F. E. Verduyn Lunel
- Subjects
Adult ,Eye Movements ,genetic structures ,Electrodiagnosis ,Computer science ,Physiology (medical) ,Saccades ,medicine ,Humans ,Computer vision ,medicine.diagnostic_test ,business.industry ,Arden ratio ,Eye movement ,Electrooculography ,Optokinetic reflex ,Middle Aged ,Clinical routine ,eye diseases ,Sensory Systems ,Ophthalmology ,Eye position ,sense organs ,Artificial intelligence ,business - Abstract
The measurement of the light rise of the corneoretinal potential in the clinical routine depends critically on the constancy of the eye movements made by the subject. To verify to what extent the variability of the Arden ratio can be explained by the variability of these eye movements, an infrared scleral reflection technique was applied in order to monitor eye position and electrooculogram simultaneously. The data obtained in 10 normal subjects show that not only is the variability reduced substantially by correction for the actual eye movement, but also the routine procedure gives a systematic underestimation of the ratio. Monitoring eye movements makes available the use of eye movements of arbitrary size (e.g., optokinetic nystagmus), allowing for application of the method in uncooperative subjects such as children.
- Published
- 1989
38. Early Physiological Effects of Lithium Treatment: Electrooculographic and Adaptometric Findings in Patients with Affective and Schizoaffective Psychoses
- Author
-
W. P. Kaschka, M. Korth, and T. Mokrusch
- Subjects
Adult ,Affective Disorders, Psychotic ,Male ,medicine.medical_specialty ,Lithium (medication) ,Dark Adaptation ,Lithium ,Gastroenterology ,Lithium.serum ,Internal medicine ,Healthy volunteers ,Humans ,Medicine ,Pharmacology (medical) ,In patient ,Prospective cohort study ,medicine.diagnostic_test ,Adaptation, Ocular ,business.industry ,Arden ratio ,Biological Transport ,General Medicine ,Electrooculography ,Middle Aged ,Psychiatry and Mental health ,Psychotic Disorders ,Female ,business ,medicine.drug - Abstract
Electrooculography allows to measure the fundocorneal potential, a standing potential of the eye, under the conditions of light and dark adaptation. The results are expressed as the so-called Arden ratio. As was demon-strated by others in healthy volunteers, the Arden ratio, on the average, de-creases under Lithium treatment. However, in individual cases it can also remain unchanged or even rise. We have performed electrooculographic and adaptometric examinations in ten patients with affective disorders (DSM-III, 296. XX) and schizoaffective psychoses (DSM-III, 295.70). The criteria for the assignment of patients to lithium treatment were derived from a study by Angst. Arden ratios were determined six times, respectively, before lithium application and after a therapeutic lithium serum level (0.6-0.8 mmol/l) had been reached (cf. 5). The values observed during lithium treatment were significantly lower than those measured before lithium application. Dark adaptation, as measured using an adaptometer according to Goldmann-Weekers, was disturbed under lithium. The potential predictor function of these findings with regard to the lithium response is being investigated by means of a prospective study.
- Published
- 1987
39. Toxic Retinopathy in Malaria Tropica
- Author
-
Barbara Schmidt
- Subjects
medicine.medical_specialty ,Retina ,genetic structures ,Arden ratio ,Chloroquine diphosphate ,Biology ,Pharmacology ,medicine.disease ,eye diseases ,Surgery ,medicine.anatomical_structure ,medicine ,sense organs ,Toxic retinopathy ,Malaria - Abstract
The retina is known to be vulnerable to many toxic agents. For many years antimalarial drugs have been known to exert an apparently selective toxic effect on the eye. The doses used in malaria have relatively few secondary effects.
- Published
- 1978
40. Clinical electro-oculography
- Author
-
Pinckers A
- Subjects
Base line ,Eye Diseases ,Computer science ,Electro oculogram ,Arden ratio ,Absolute level ,General Medicine ,Electro-oculography ,Clinical routine ,Ophthalmology ,Electrooculography ,Reference Values ,Optometry ,Humans - Abstract
In clinical routine EOG we are dealing with a base line or lightinsensitive potential and a lightsensitive potential, the latter consisting of at least two different oscillations, a fast negative and a slow positive one. Any judgement of EOG without referring to the absolute level of the baseline is an incomplete one. It is no longer justified to refer to the Arden ratio as a unique parameter for EOG normalty or abnormalty. Our knowledge about the generating mechanisms of the different EOG components is insufficient. Clinical EOG examination is one way to better understanding. Statistical evaluation is not easy because of the considerable inter- and intraindividual variations. The study of uniocular diseases or affections may solve some of our problems.
- Published
- 1979
41. Normal values in clinical electrooculography. III. Numerical evaluation of two dimensionless EOG parameters
- Author
-
Erik Krogh
- Subjects
Adult ,Male ,medicine.diagnostic_test ,Adolescent ,Sample (material) ,Mathematical analysis ,Arden ratio ,General Medicine ,Electrooculography ,Normal values ,Middle Aged ,Ophthalmology ,Distribution (mathematics) ,Evaluation Studies as Topic ,Reference Values ,medicine ,Humans ,Statistical dispersion ,Female ,Clinical Competence ,Mathematics ,Dimensionless quantity ,Aged - Abstract
The distribution of the Arden ratio (A) and another dimensionless EOG quantity (G) devised by Gliem (1971) in a sample of normal human subjects are presented. The minimum, median and maximum values for A are 148--241--449 and for G 34-88-167. A demonstrates a smaller degree of dispersion than G, the latter resembling in this respect the EOG potential parameters of the same sample. The average accumulation of errors due to inaccurate assessment of the included potential figures is almost equal in the functions of A and G. Divergencies between the figures from the present and earlier investigations are discussed together with the general advantage of dimensionless EOG parameters. It is concluded that the present investigation has not demonstrated the need to replace or supplement the Arden ratio by the Gliem quantity.
- Published
- 1977
42. Some Considerations regarding the Effect of Antimalarial Drugs on the EOG and the ‘Macular Eog’
- Author
-
A. Bronner, H. Franck, and J. C. Muller
- Subjects
Time parameter ,medicine.diagnostic_test ,Computer science ,Arden ratio ,Clinical value ,medicine ,Optometry ,Electrooculography ,Pigment Alterations - Abstract
Since the early work in electrooculography performed by Arden and Francois, little real progress has been made, either from a theoretical point of view or in the clinical applications of the test. Amplitude changes give information about the standing potential, but, in fact, we still know very little about the mechanisms involved. The ‘Arden ratio’ has a clinical value insofar that it allows the detection of pigment alterations. The EOG also allows us to follow the progression of patients being treated with potentially retinotoxic antimalarial drugs. Traditionally, the only parameter measured is ‘amplitude’, In this paper, we want to draw attention to the ‘time’ parameter. Only a few authors have taken this time parameter into consideration (Arden & Barrada, 1962; Gliem, 1971; Krogh, 1975).
- Published
- 1978
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