Alcohol- and Light-induced Electro-oculographic Responses: Variability and Clinical Utility

Abstract

The alcohol-induced electro-oculographic (EOG) response has been proposed by Arden as an indicator of retinal pigment epithelial (RPE) integrity. We have evaluated the consistency of the alcohol-EOG with respect to clinical applicability and compared this response to the ISCEV-standard EOG. We recorded, in a group of normal subjects (n=29, 14 men with mean age 42+/-11 years and 15 women with mean age 36+/-13 years), the alcohol response to a single oral dose of ethanol at 160 mg/kg (as 40 proof vodka, drunk in 15 s after 12 h of fasting), followed by an ISCEV-standard EOG 90 min after alcohol administration. Blood alcohol levels were monitored at regular intervals with a breath analyzer. We found a wide range of amplitudes in both light and alcohol responses among participants, from minimal to large values. Subjects had a wide range of blood alcohol concentrations from 0.02 to 0.10%; near the time of the response peak, but there was no relationship between alcohol levels and peak/baseline ratios. In addition, there was no relationship between alcohol peak/baseline ratio and the Arden ratio. Neither the alcohol nor the light response parameters showed any relationship with age or gender. Some of the inter-individual variability in the EOG response to alcohol may reflect variable absorption of oral alcohol. The alcohol-induced EOG has too broad a range of responses to be useful clinically for the one-time evaluation of individual patients. We have similar concerns regarding clinical applications of the standard light-induced EOG.

Alcohol- and Light-induced Electro-oculographic Responses in Age-related Macular Degeneration & Central Serous Chorioretinopathy

“…Nevertheless, these tests would have clinical value if they proved to be sensitive to disease (even if non-specific). In our experience, the Alc-EOG (and indeed also the Li-EOG) appears too variable between subjects to be useful for evaluating individual patients [15]; but group means could still be important for characterizing pathology. To date, the limited number of reports on nonphotic EOG responses in ARMD patients have not shown any positive correlation [7,8] except for the recent Alc-EOG study by Arden and Wolf [14].…”

“…Normal Controls: 29 healthy volunteers (15 women, age 24-72 years, mean age 36; 14 men, ages 24-57, mean age 42) with no known ocular or systemic diseases, who also served as normal controls in our companion paper [15], were recruited from the local community. We did not further subdivide these controls by age, since both our data on the Alc-EOG and Li-EOG [15] and that of Arden and Wolf [14] has shown no relationship with age.…”

Nifedipine alters the light-rise of the electro-oculogram in man

“…b and c show an individual's traces for the ERGs before and after nifedipine respectively the participants' responses. The variability of the EOG has been reported [26], and for this reason we excluded participants whose NiEOG was within 10% of the initial LEOG. Considering the low oral dose used, and the large effects seen in the light-rise, it is reasonable to accept that nifedipine alters the light-rise in man, and that the L-type calcium channel is involved in generating this component of the EOG.…”

Electrophysiological tests in the assessment of visual disorders

“…Por tanto, deben tener mecanismos distintos en su inicio y convergen en uno común 27 . No obstante, las respuestas obtenidas con luz, y más aún con alcohol, son muy variables entre unos individuos y otros y también dentro del mismo individuo, lo cual resta utilidad clínica 28 .…”

“…El EOG es dato de valor diagnóstico en la distrofia macular viteliforme de Best; en otras alteraciones maculares o del EPR está dentro de valores normales o no concluyentes 28,29 . En patologías difusas como la retinosis pigmentaria se altera, pero es mucho menos sensible que el ERG-F.…”