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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.

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.

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.

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.

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.

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.

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.

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.

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).

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.

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.

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.

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.

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.

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.

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.

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.