Steady-state visual evoked cortical potentials from stimulation of visual field quadrants

The effects of check size and stimulus size were investigated to optimize the steady-state visual evoked cortical potentials from pattern-reversal stimulation of the visual field quadrants. Check sizes of 15, 30, 60, 90, 120 and 180 were investigated at a pattern reversal rate of 11.6 per second for field sizes varying from 2° × 2° to 24° × 24°. The visual evoked cortical potentials were recorded from mid occipital, right occipital and left occipital positions. In the inferonasal quadrant, the largest amplitudes were obtained with 30 and 60 check sizes; however, for these check sizes, the visual evoked cortical potential yielded limited additional information for field sizes greater than 4° × 4° and 6° × 6°, respectively. When a field size of 12° × 12° was investigated, a 90 check size was optimal. The results indicated hat, with the above recording positions and check sizes of 15 to 120, there is an optimal number of pattern elements, 40 to 100, for stimulation of the inferonasal quadrant. This should be taken into account when a check size is selected to investigate a field quadrant of a particular size. Digital signal processing techniques were applied to analyze the visual evoked cortical potential, and the system shows promise for objective examination of the visual field.     

Influence of simultaneous pattern-reversal electroretinogram recording on visual evoked potentials

Little is known about the influence of the presence of a gold-foil electrode on pattern-reversal visual evoked potential recording, although simultaneous pattern-reversal electroretinography has been applied in several clinical investigations. We compared the results of pattern-reversal visual evoked potentials simultaneously recorded with pattern-reversal electroretinograms with those obtained during separate pattern-reversal visual evoked potential recording in 10 normal subjects. Transient response (reversal rate, 1 Hz; check size, 30) and steady-state response (reversal rate, 5 Hz; check size, 120, 60, 30, 15 and 7.5) were analyzed under the stimulus contrast condition of 90%. Neither P100 latency in transient responses nor amplitudes in steady-state responses exhibited significant change at any check size when they were recorded separately or simultaneously with pattern-reversal electroretinograms. The results suggest that the gold-foil electrode exerts no significant influence on pattern-reversal visual evoked potentials. Simultaneous pattern-reversal electroretinogram and visual evoked potential recording is therefore confirmed to be a clinically useful method. This procedure makes the synchronous recording of both responses possible under the identical stimulus conditions.     

Visual evoked potentials in macular hole

Pattern reversal visual evoked potentials (VEPs) with checks of 50 and 12 were recorded in 15 patients with idiopathic unilateral macular hole. VEPs from the affected eyes were reduced in amplitude compared with those from the fellow eyes, especially with checks of 12 (percentage of the amplitude in the affected eye to that in the fellow eye was 86% ± 19% with checks of 50 and 61% ± 35% with checks of 12). The latencies showed no statistically significant difference between the affected and the fellow eyes, although a marked interocular delay was found in a few patients. The degree of amplitude reduction and interocular delay had no relation to the size of the macular hole or visual acuity. The effects of experimental scotomata of various sizes on the VEPs, which were evaluated in nine normal subjects, were also variable among the subjects. We conclude that although the macula predominantly participates in the pattern VEP, an estimation of the extent of macular pathology from the VEP changes may be difficult because the VEP changes induced by a macular hole have wide individual variation and have no relation to the size of the hole.     

Electrophysiological evidence that early glaucoma affects foveal vision

The pattern electroretinogram (PERG) and visual evoked potential (PVEP) were recorded simultaneously using a 1.1 cpd pattern which was counterphase modulated at 1 Hz. The responses of ocular hypertensive (OHT) eyes (with normal visual fields) and eyes with early glaucoma (with early visual field defects and/or early cupping of the optic nervehead) were compared to age-matched normal observers. All patients (26 eyes) and normal observers (14 eyes) had normal transient flash electroretinograms. Delays were seen in mean PERG latency in both OHT and early glaucoma eyes, while mean PERG amplitude was significantly reduced only in the early glaucoma eyes. The PVEP responses were unmeasurable in 11/26 patient eyes because the waveforms were grossly abnormal in shape, making it impossible to identify the N- and P-components. The data were categorized in this manner: a patient response was considered abnormal if latency or amplitude exceeded normal limits (PERG or PVEP) or if the waveform was unmeasurable due to its shape (PVEP only). Of the 26 patient eyes, we found that 8 eyes had normal PERG and PVEP, 11 eyes had abnormal PERG and PVEP, one eye had an abnormal PERG and a normal PVEP, and 6 eyes (3 patients) had a normal PERG and an abnormal PVEP. These data support the proposition that foveal vision (as assessed by the PVEP) may be affected by early glaucomatous damage. The relationship between the PERG and PVEP also was evaluated using a new measurement which we call the latency window. Using this measurement, 15/26 patient eyes were abnormal - 9 of these had unmeasurable PVEPs. This measurement could be useful in classifying W-shaped PVEPs as normal or abnormal.This study was supported in part by Grants EY01708 and EY01867 from the National Eye Institute, Bethesda, MD, by Fight For Sight Grant-in-Aid G-274, and by an unrestricted grant from Research to Prevent Blindness, Inc., New York, NY.     

The effect of motion on pattern-onset visual evoked potentials in adults and children

Visual evoked potentials can be elicited by a variety of visual stimuli, including pattern-onset and motion-onset. It may be desirable to combine pattern-onset with motion-onset stimuli, for example, to make a direct comparison between optokinetic nystagmus and visual evoked potential acuity thresholds. Both procedures employ grating stimuli; however, the gratings must be moving to produce optokinetic nystagmus. We compared pattern-onset visual evoked potentials with both a static and a moving pattern to investigate the effect of motion on the pattern-onset visual evoked potential waveform. Visual evoked potential recordings were made from 10 adults (aged 20–37 years) and 10 children (aged 5–7 years) with the active electrode at O_z. Stimuli consisted of onset of high-contrast vertical bars of three sizes (12, 30 and 60) both with and without motion (3 cycles/s). In a subgroup of subjects, visual evoked potentials were recorded to motion onset of constantly present gratings. Motion of the pattern had no significant effect on any of the latency components of the visual evoked potential waveform in adults or children. The amplitude of the C2–C3 component was significantly increased (p < 0.001) in adults. The motion appears to add a late negative component to the visual evoked potential similar to that produced by the motion-only stimulus. The latency of the early components of the pattern-onset visual evoked potential was unaffected by the presence of motion. Therefore, pattern-onset visual evoked potentials with moving gratings could be used to estimate visual acuity, and direct comparisons could be made between visual evoked potential and optokinetic nystagmus acuity thresholds with the use of the same stimulus parameters.Abbreviations ANOVA analysis of variance - OKN optokinetic nystagmus - ON-M onset with motion - ON onset without motion     

Effect of defocusing and of distracted attention upon recordings of the visual evoked potential

Pattern reversal visual stimuli are used to evoke potentials (VEPs) for assessment of visual acuity and for localizing defects along the visual pathways. Our goal was to assess the importance of attention and defocusing to the recordings of pattern VEP. Forty-one volunteers with normal (6/6) corrected visual acuity participated in this study. Twenty-one were asked to defocus intentionally the visual stimulus (located 200cm away) by fixating at a target 25 or 50cm from the eye. Twenty other subjects performed auditory tasks to distract their attention from the visual stimulus. Pattern VEPs were elicited by different check sizes. The amplitude and time-to-peak of the P₁₀₀ wave were measured. Intentional defocusing caused amplitude reduction and prolongation of the time-to-peak in young subjects (20–34years old). With the smallest checks used (7.5) we could not record a reliable response from 43 of the young subjects (6 out of 14). In older patients (35–61years old), intentional defocusing induced negligible effects on pattern VEPs regardless of check size. There were no effects of auditory distraction upon the pattern VEPs. Our data suggest that intentional defocusing can produce false positive results (reduced VEP with prolonged time-to-peak) only when small checks are used in young subjects. Divided attention has negligible effect on the recordings of pattern VEPs. With proper controls, the pattern VEP test can be used for objective assessment of visual function.     

Methods of visual acuity determination with the spatial frequency sweep visual evoked potential

Purpose The spatial frequency sweep visual evoked potential (sVEP) is used to rapidly determine visual acuity in children or non-responsive patients. Two techniques have been used to separate signal from noise: (1) the 95% confidence interval for the signal amplitude (95% CI) or (2) the amplitude of a Fourier frequency adjacent to 2×the signal frequency (DFT). The purpose of this study is to determine if there is a significant difference in acuity estimates with these techniques.Methods Ten normal subjects (approximately 0.00logMAR acuity) and 11 patients with decreased visual acuity took part in this project. Stimulus production and data analysis were done with an Enfant 4010 (Neuroscientific Corp). Standard VEP recording techniques were employed. The stimulus was a horizontal-oriented, sine wave grating that swept up the spatial frequency spectrum (contrast 80%, temporal reversal rate 7.5Hz). Sweeps were repeated until the confidence intervals for the data were no longer decreasing. The Bailey LovielogMAR chart was used to determine visual acuity. A line was fit to the high spatial frequency data using either the 95% CI or the DFT as the noise estimate. By using these linear equations, acuity estimates were obtained at 0, 1, and 2V signal amplitudes.Results The average logMAR acuity for the subjects with normal acuity was –0.06±0.070 (SD). The sVEP acuity estimates were 0.08±0.098, 0.18±0.092, and 0.33±0.195 (0, 1, and 2V extrapolations) with the 95% CI used as noise and 0.07±0.100, 0.18±0.103, and 0.33±0.202 (0, 1, and 2V extrapolations) with the DFT used as noise. By using the average noise from the Fourier frequency as the extrapolation level, the acuity was 0.10±0.098logMAR. The averagelogMAR acuity for the subjects with decreased visual acuity was 0.67±0.306 (SD). The sVEP acuity estimates were 0.53±0.175, 0.66±0.171, and 0.88±0.295 (0, 1, and 2V extrapolations) with the 95% CI used as noise and 0.53±0.179, 0.65±0.176, and 0.86±0.268 (0, 1, and 2V extrapolations) with the DFT used as noise. By using the average noise from the Fourier frequency as the extrapolation level, the acuity was 0.57±0.186logMAR. No significant difference was found between the two acuity estimate techniques for all of the subjects (repeated measures ANOVA, p=0.16, F₂₀=2.131). The sVEP estimates of acuity to the 0V and noise levels were not significantly different from the logMAR acuity (paired t-test, all p values >0.05).Conclusions The results indicate that the sVEP acuity does not depend on the noise estimation technique. In agreement with prior studies, the sVEP acuity underestimates the logMAR acuity in normally sighted individuals by about an octave.     

Visual evoked cortical potential can be used to differentiate between uncorrected refractive error and macular disorders

The visual evoked cortical potential (VECP) is widely used to verify complaints of reduced visual performance and to identify the site of the disorder. In this study, we investigated the correlation between reduced visual acuity and VECP in volunteers with normal corrected visual acuity and in patients suffering from inherited macular degeneration or from age related macular degeneration (ARMD). Flash evoked VECP was not affected by the visual acuity in the cases of refractive error and in ARMD patients but was reduced in amplitude and delayed in implicit time in the patients suffering from inherited macular degeneration. The VECP elicited by pattern reversal checkerboard (PVECP) was not affected by the quality of the visual image in volunteers with uncorrected refractive error when checks of 60 or larger were used but were considerably reduced in size and prolonged in implicit time for checks smaller than 15. In both groups of patients suffering from macular dysfunction, pattern reversal VECP was very subnormal and was characterized by prolonged implicit time compared to values expected from their visual acuity. These findings indicate that the PVECP does not directly correlate with visual acuity but rather with foveal function. Therefore, we suggest that recordings of PVECP can be used to differentiate between refractive error and macular disorders as causing reduction in visual acuity when other clinical signs are missing or not available.     

Discriminative power of visual evoked potential characteristics in multiple sclerosis

To investigate the discriminative power of pattern-reversal visual evoked potential characteristics (peak latencies and amplitude) and to test whether the addition of visual evoked potential amplitude can increase the power of the visual evoked potential in the diagnosis of multiple sclerosis, we retrospectively studied visual evoked potentials in 59 patients with definite multiple sclerosis and 126 control subjects. Two check sizes (17 and 10) were used. Females had significantly higher amplitudes and shorter latencies than males. N80 latency showed a gradual increase and P100 amplitude a decrease with age. P100 latency was stable between the ages of 20 and 55 years but was increased in childhood and the elderly. The significance of visual evoked potential peak latencies and amplitude in separating the two groups was investigated by means of a (multivariate) discriminant analysis. The visual evoked potential with a pattern of 10 could be measured in 58% of patients with multiple sclerosis. The exclusive use of the P100 amplitude in the discriminant analysis resulted in a percentage of correctly classified cases of 84%, whereas for P100 and N80 latency it was 85% and 90%, respectively. With the 17 pattern, the N80 latency yielded also a higher correct percentage than did the P100 latency. Although N80 latency is, to a greater extent than P100 latency, influenced by age, sex and size of stimulus pattern, when these influences are accounted for, the N80 latency is a more sensitive measure than P100 latency in the classification of multiple sclerosis. Combined use of latency and amplitude for discriminant analysis yielded no significant improvement of the percentage of correctly classified cases.Abbreviations MS multiple sclerosis - SD standard deviation     

Effect of stimulus check size on multifocal visual evoked potentials

In this study we examined the effects of varying stimulus check size on multifocal visual evoked potential (VEP). We also evaluated the currently used cortical scaling of stimulus segments. The ObjectiVision^TM multifocal objective perimeter stimulates the eye with random check patterns at 56 cortically scaled segments within the visual field extending to a radius of 26°. All cortically scaled segments have equal number of checks, which gradually increase in size from the center to the periphery, proportional to the size of the segment. Stimuli with 9, 16, 25, 36 and 49 checks/segment were tested on 10 eyes belonging to 10 normal subjects. The check size varied inversely with number of checks per segment. VEP was recorded using bipolar occipital cross electrodes (7min/eye), the amplitude and latency of responses obtained were compared with the check size at different eccentricities. Our findings suggest that the existing setting with 16 checks/segment subtending 26 to 140 from center to periphery, is the most effective amongst all the check sizes. Decreasing the check size prolongs the latency in the central field only. Cortical scaling of segments generates responses of the same order of magnitude throughout the field, but could be improved slightly to enhance the signal from the outer two rings.     

The global burden of trachomatous visual impairment: I. Assessing prevalence

This paper summarizes primary epidemiologic studies of trachomatous blindness to develop age-/sex-/region-specific estimates of the global prevalence of trachomatous blindness and low vision. These studies are first examined for their validity and then employed to derive a minimum prevalence of trachomatous visual impairment. This method yields a global total for 1990 of approximately 640,000 cases of trachomatous blindness, corresponding to a prevalence of 0.12/1,000 (lower and upper bounds, 0.10 to 0.14/1,000). When those with low vision due to trachoma are included, 1.5 million cases of visual impairment are estimated, corresponding to a prevalence of 0.28/1,000 (lower and upper bounds, 0.15 to 0.75/1,000). A second approach, labeled the projected prevalence of trachomatous visual impairment, selects country-wide studies to derive representative regional prevalence values. A global total of 2,899,000 blind (projected prevalence of 0.55/1,000 with lower and upper bounds, 0.37 to 0.83/1,000) is estimated for 1990. With trachomatous low vision included, greater than 6.7 million individuals in 1990 have visual impairment from trachoma (projected prevalence of 1.28/1,000 with lower and upper bounds, 0.53 to 4.29/1,000). Analysis of the distribution of the global prevalence by age, gender, visual acuity and region provide direction for trachoma research and programme priorities. Attention is drawn to the limited studies and resulting wide variation in the estimates of trachomatous visual impairment prevalence as indicated by the lower and upper bound estimates. It is recommended that this epidemiologic uncertainty be reflected in global and regional estimates of trachomatous visual impairment prevalence in order to draw attention to how little is known and emphasize the need for further surveys. A second paper incorporates these findings in an assessment of the global burden of trachomatous visual impairment.Supported by the Edna McConnell Clark Foundation.     

A study of the effects of contrast change on pattern VEPs, and the transition between onset, reversal and offset modes of stimulation

We studied the relationship between the visual evoked potential (VEP) components by tracing the transition from onset/offset mode of stimulation to the reversal mode by a series of contrast change steps. VEPs on the ipsilateral and contralateral side of the scalp with respect to the left half-field checkerboard stimulus (checksizes: 12, 50 and 80) were recorded in 15 subjects. Eight contrast steps for each checksize were recorded. Each test step consisted of the alternation of a constant high contrast checkerboard (A), with a second checkerboard (B) in which the contrast was changed. Checkerboard B was initially of identical spatial phase to A, but contrast was reduced systematically until B was a uniform grey field (i.e. onset/offset). In subsequent steps checkerboard B was of opposite spatial phase and contrast was increased until the final step when B was of equal high contrast (i.e. full reversal). All ipsilateral and contralateral onset components, ipsilateral offset components, and the reversal P100 component significantly enlarged with increasing contrast. The extent of amplitude change with contrast was greatest for offset, followed by onset and then reversal. A clear association could be discerned between all offset and reversal components. Onset CI and CII appeared to be related to the reversal P100 and N145, respectively. When small 12 checks were used, onset Co appeared to have common features with the reversal N80. The contralateral onset P105 component did not have a comparable component in the reversal mode.     

The topographic distribution of the magnetic P100M to full- and half-field stimulation

Visual evoked magnetic responses were recorded to full-field and left and right half-field stimulation with three check sizes (70, 34 and 22) in five normal subjects. Recordings were made sequentially on a 20-position grid (4 × 5) based on the inion, by means of a single-channel direct current-Superconducting Quantum Interference Device second-order gradiometer. The topographic maps were consistent on the same subjects recorded 2 months apart. The half-field responses produced the strongest signals in the contralateral hemisphere and were consistent with the cruciform model of the calcarine fissure. Right half fields produced upper-left-quadrant outgoing fields and lower-left-quadrant ingoing fields, while the left half field produced the opposite response. The topographic maps also varied with check size, with the larger checks producing positive or negative maximum position more anteriorly than small checks. In addition, with large checks the full-field responses could be explained as the summation of the two half fields, whereas full-field responses to smaller checks were more unpredictable and may be due to sources located at the occipital pole or lateral surface. In addition, dipole sources were located as appropriate with the use of inverse problem solutions. Topographic data will be vital to the clinical use of the visual evoked field but, in addition, provides complementary information to visual evoked potentials, allowing detailed studies of the visual cortex.     

Information coding in the visual system: A new hypothesis

Experiments on subjective color sensations using a special signal generator and a standard TV monitor (black and white) led to a new hypothesis on information coding in the visual system. According to this hypothesis a trigger signal is required which restores the phase correlation of the pulse-coded spiking of the neurons transmitting visual information from the eye to the brain. The shift effect ( periphery effect), either artificially induced or initiated by microsaccades, might act as the postulated trigger.

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Zusammenfassung Experimente über subjektive Farbwahrnehmungen auf einem handelsüblichen Fernsehschirm (schwarz-weiß) führten zu einer neuen Hypothese über die Verschlüsselung visueller Information. Danach ist ein Trigger-Signal erforderlich zur Wiederherstellung der Phasen-Beziehung der Puls-kodierten Aktionspotentiale der Neurone, die die visuelle Nachricht vom Auge zum Gehirn übertragen. Der shift-effect (Peripherie-Effekt) — entweder künstlich oder durch Mikro-Sakkaden ausgelöst — könnte als der notwendige Trigger dienen.

     

Epidemiological aids to clinical decision making in primary open angle glaucoma

We have described the epidemiological analysis of one aspect of the King's College Hospital computerised data base; namely initial intraocular pressure as an indicator of visual field loss. The methods involved the use of the four-fold table to determine sensitivity and specificity at different pressure levels. From these results (1) the changes in the pre and post test probability of field loss are calculated and (2) a sensitivity/specificity trade off curve or decision curve is constructed. In this way the optimal cut-off level or operating point for a population of specific type and composition can be determined. The factors concerned in decision making are always complex but such an approach allows a rational and quantifiable alternative to reliance on clinical impression and intuition. The results have significance in relation to decisions on the management of patients and on population screening programmes for glaucoma.     

Die Fernsehbildanalyse

Zusammenfassung Beschreibung einer Methode zur objektiven Perimetrie. Eine infrarotsensible Fernsehkamera wurde in ein Projektionsperimeter eingebaut. Sie ermöglicht die Abbildung des Probandenauges auf dem Monitor bei gleichzeitiger Fixationskontrolle unabhängig von der jeweiligen Umfeldleuchtdichte. Die speziell für das vorliegende Problem selbst entwickelte Fernsehbildanalyseeinrichtung registriert den konsensuellen Pupillenreflex, ausgelöst durch den Prüfpunkt des Perimeters. Am Beispiel von vier gesunden Versuchspersonen wird die Methode auf ihre Brauchbarkeit hin geprüft. Der Verlauf der sensorischen und der pupillomotorischen Schwelle auf dem Meridian (135°) des Gesichtsfeldes wurde bestimmt. Untersucht wurde im photopischen Bereich bei einer Umfeldleuchtdichte von 10 asb mit zwei Prüfpunktdurchmessern, 27 und 7. Der Verlauf der Profile im statischen Gesichtsfeld mit einem Prüfpunkt von 7 Durchmesser ist annähernd parallel. Der Empfindlichkeitsunterschied zwischen Sensorik und Pupillomotorik beträgt etwa 10 dB.

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Summary An infrared-sensitive TV Camera has been fitted into a projection perimeter, which allows to control fixation independent of the particular background illumination. The consensual pupil light reflex, triggered by the test light of the perimeter, is measured and registered with a special TV processor designed for this purpose. The method was tested for its efficiency on four healthy volunteers. The course of sensory and pupillomotor thresholds were measured on the 135° meridian of the visual field. Determinations were conducted in the photopic range of 10 asb background illumination with two test points of 27and 7. A difference of 10 dB was found between the sensory and pupillomotor thresholds.

     

Self-administered automatic sight-testing

A feasibility study to estimate the extent to which self-administered computerized sight-testing instruments would be acceptable to patients and staff in a hospital outpatient eye department has been carried out. Visual acuity was measured in two ways for each of 86 patients in the age range 20–79 years; Snellen acuity was compared with the screen-based Landolt C test. The patient was seated in front of the computer controlled display, supplied with tape-recorded instructions: his/her progress was monitored without intervention unless there were obvious difficulties. The mean acuities as measured by the two methods did not differ significantly from each other, with similar variances. More than 70% of patients managed the self-administered test without any help at all, only 4–5% failing completely. The computerized test was favoured by most except the oldest patients. It forms therefore a sound basis for further development on a large scale.Abbreviations Chart also C Snellen measured visual acuity - Screen also S computer tested visual acuity     

Pattern VEP is a useful technique in monitoring the effectiveness of occlusion therapy in amblyopic eyes under occlusion therapy

Purpose To evaluate the effectiveness and clinical significance of pattern visual evoked potential (P-VEP) parameters on visual acuity in amblyopic patients under occlusion therapy.Methods A total of 34 consecutive children with anisometropic amblyopia were included in this study. All patients underwent a full initial ophthalmologic and orthoptic evaluation. P-VEP test was performed in all cases and binocular vision was tested and recorded with Worths four-dot test and Bagolini striated glasses at each visit. Part-time occlusion therapy was performed by using adhesive patches.Results The mean (±SEM) cycloplegic refractive error was +5.6± 0.6 diopters (D) in the amblyopic eyes and +1.8±0.2 D in the normal eye. The mean levels of best-corrected visual acuity were statistically differed between each measurement for occlusion therapy (for each, p<0.05). The ratio of the patients with binocular vision increased after 6months occlusion therapy and the difference was statistically significant (p<0.05). In addition, P100 amplitude improved at each visit and the difference was significant when compared with baseline values (for each,p<0.05).Conclusions P100 amplitude of the P-VEP test parallels the improvement in subjective visual acuity in amblyopic eyes under occlusion therapy. Therefore, this test may be useful in monitoring the visual acuity in the preverbal or non-verbal patched patients.     

The effect of contrast reduction on pattern-reversal VEPs in suspected multiple sclerosis and optic neuritis

A retrospective study was conducted to investigate whether the use of low-contrast stimuli in addition to the standard high-contrast stimuli would increase the sensitivity of the pattern-reversal P100 when testing for multiple sclerosis (MS) and optic neuritis (ON). We found that there was a statistically significant increase in the number of abnormal results when using 25 checks, but not for 50 checks. Examination of patient records showed that VEP abnormalities to low-contrast stimuli only was not prognostic for subsequent development of multiple sclerosis.     

Cyclosporine-A in the treatment of serpiginous choroiditis

Summary Seven patients affected by bilateral inflammatory serpiginous choroiditis have been treated with Cyclosporine-A for 6-21 months. Nine outof the fourteen eyes showed a significant improvement in their visual acuity; five eyes did not change.Cyclosporine-A may, therefore, be considered effective in the treatment of this disease.Its usefulness seems to be greater when the serpiginous choroiditis is in its acute stage; chronic stages, however, also seem to improve under treatment.Its main indication is, in our opinion, the involvement of the macular region of the second eye, when the first eye is already damaged. We consider Cyclosporine-A, in these situations, to be a first choice treatment.