The purpose of this study was to standardize normal EOG values in Koreans. The subject were 23 normal Koreans varying in age 16-40 yrs with no ocular abnormality or disease. EOG was recorded by Life-Tech instrument Model 7310 ERG/EOG stimulator, Model 7101 ERG/EOG analyzer. The result were as follows. Dark trough potential was 235.65 +/- 71.59 uV, Light Peak Potential was 402.60 +/- 103.09 uV, EOG ratio(Lp/Dt) was 1.74 +/- 0.23, Dark trough time was 14-15 minutes, and light peak time was 10 minutes.
Electrooculography

Manifest latent nystagmus (MLN) combined with esotropia may be confused with the nystagmus blockage syndrome (NBS), so the NBS may be overdiagnosed. The NBS is similar to MLN in the characteristics of the nystagmus and the clinical features, thus two diseases must be differentiated. In order to differentiate the MLN with esotropia from the NBS, accurate calibration of slow phase of nystagmus is essential with the aid of electro-oculography (EOG). With EOG recording, authors report a case of MLN associated with esotropia which may be misdiagnosed as the NBS.
Calibration ; Electrooculography ; Esotropia

The latent nystagmus seems to be absent when both eyes are open, but on covering one eye, bilateral jerky nystagmus is evoked with the fast phase toward the uncovered eye. The confirmed diagnosis of latent nystagmus can be made with the aid of the Electro-oculography (EOG). On EOG recording, we experienced a case of latent nystagmus in light, which showed the characteristics of infantile nystagmus in darkness.
Darkness ; Diagnosis ; Electrooculography

PURPOSE: To report herein on Nystagmus Acuity Estimator Function (NAEF) based on the foveation time, obtained by analyzing waveforms of infantile nystagmus patients and comparing the results with the patients' actual visual acuity. METHODS: Electro-oculographic data of 27 patients with infantile nystagmus were reviewed. Data of patients only with jerk type nystagmus and reliable visual acuity were analyzed. The foveation time was measured, and NAEF was calculated and compared with the patients' actual best corrected visual acuity. RESULTS: A correlation analysis of the patients' best corrected visual acuity with NAEF was performed, and the retrieved coefficient was 0.4266. The p-value calculated using the Pearson correlation coefficient was 0.0282, implying that high NAEF correlates positively with visual acuity. CONCLUSIONS: Estimated visual acuity, calculated based on the waveforms, positively correlates with the patients' actual visual acuity with statistical significance. However, since the foveation time can be measured only in the patients with jerk-type nystagmus waveforms, further study should be performed on the measurement of the foveation time with other waveforms. Furthermore, the present study shows that such analysis is possible with electrooculogram settings in most general hospitals.
Electrooculography ; Hospitals, General ; Humans ; Visual Acuity

The authors analysed eleven patients with latent nystagmus who were diagnosed by clinical manifestation and electrooculography during six months. Among them, six patients had monocular amblyopia, four had binocular amblyopia and only one had normal visual acuity. All of them had manifest latent nystagmus which had a small amplitude of nystagmus in binocular fixation. Two of them showed typical latent nystagmus, jerky wave form characterized by decreasing velocity in slow phase and directing to fixing eye. Seven patients showed typical latent nystagmus wave form associated with pendular wave form and two patients showed jerky wave form with increasing velocity in slow phase. Therefore nine patients had componant of infantile nystagmus wave form. Ten of them had strabismus. Among them, five patients had hyper tropia. Three of the hypertropic patients showed dissociated vertical deviation. The authors suggest that the latent nystagmus is a kind of infantile nystagmus, and abnormal ocular conditions such as strabismus and amblyopia affects the infantile motor nystagmus.
Amblyopia ; Electrooculography ; Humans ; Strabismus ; Telescopes ; Visual Acuity

The eye-computer interaction technology based on electro-oculogram provides the users with a convenient way to control the device, which has great social significance. However, the eye-computer interaction is often disturbed by the involuntary eye movements, resulting in misjudgment, affecting the users' experience, and even causing danger in severe cases. Therefore, this paper starts from the basic concepts and principles of eye-computer interaction, sorts out the current mainstream classification methods of voluntary/involuntary eye movement, and analyzes the characteristics of each technology. The performance analysis is carried out in combination with specific application scenarios, and the problems to be solved are further summarized, which are expected to provide research references for researchers in related fields.
Computers ; Electrooculography/methods* ; Eye Movements ; Movement

Vitelliform macular dystrophy, adult type, is a type of pattern dystrophies of the pigment epithelium characterized by autosomal daminant inheritance, mid-life onset and small, round or oval, yellow deposits located at the level of the pigment epithelium. The authors report a case of this dystrophy which showed small yellow round lesion measuring 1/4-1/3 D.D. within the macula, normal electroretinogram, subnormal electrooculogram light-peak/dark-traugh ratio. typical irregular ring-like transmitted fluorescence surrounding the central non-fluorescent Iesion and leakage from perifoveal capillaries on fluorescent angiogram.
Adult* ; Capillaries ; Electrooculography ; Epithelium ; Fluorescence ; Humans ; Vitelliform Macular Dystrophy* ; Wills

The objective visual acuity test is mandatory in certain cases, such as infants, nonverbal subjects and subjects who need legal judgements. To produce more reliable objective method, we made a new objective system for visual acuity test which is called Seohan visual acuity test(SVT). The SVT system has three elements such as stimuli, display and evaluation. For the visual stimuli, the computer program for optokinetic nystagmus(OKN)test was set up in personal computer to control the size, speed and direction of the stimuli easily. The visual stimuli are presented on HeadMounted-Display(HMD)to separate the stimuli from the environment to keep the uniform size and distance of screen to the eye of subjects and project the stimulus in full central field of patient. Electrooculography(EOG) was used to assess the visual acuity more objectively. To evaluate the usefulness of SVT, the smallest size of the stimulus to elicit OKN(objective visual acuity)with SVT was obtained in 10 eyes in each twelve grade of subjective visual acuity(decimal V). Objective visual acuity(VA)were distributed from 8.3+/-1.87 to 21.4+/-3.1 and showed high correlation(p<0.00 ). The relationship between the objective VA obtained from SVT and subjective VA make a regression line(y=-12.874X+21.303).Subjective VA could be obtained from conversion of objective VA with 95%confidence belt. In conclusion, the objective visual acuity with SVT is highly correlated with subjective visual acuity and SVT using the OKN response to stimuli presented on HMD by the computer program can be useful in assessing visual function objectively.
Electrooculography ; Humans ; Infant ; Microcomputers ; Nystagmus, Optokinetic* ; Visual Acuity*

In order to increase the performance of automatic sleep stage scoring, we propose a hybrid neural-network and rule-based expert system taking advantages of each system. The suggesting hybrid system comprises signal cleaning. feature extraction, event detection, rule-based sleep scoring and neural network classification. We selected segment based EEG features. the state of EOG. and EMG tone as a major feature set. With the extracted features, the rule-based expert system classities the sleep stages by symbolic reasoning. The scoring process of rule-based expert system comprises the single epoch reasoning based on the typical events and the multi-epoch adjusting when no events are detected. If the decision of rule-based expert system is uncertain, then these features are fed into the neural network. We used a two hidden layer feed forward network using error hack propagation algorithm. The agreement rate between human scorer and automatic algorithm were evaluated. The neural network supplements the shortcomings of rule-based system by dealing with exceptions of rules. The result shows that the compuational ol computational and symbolic intelligence is promising approach sleep signal anal) sis.
Classification ; Electroencephalography ; Electrooculography ; Expert Systems ; Humans ; Intelligence ; Sleep Stages*

As a classic eye movement method, electrooculogram (EOG) has been extensively used in many applications. There are many different types of eye movements and artifact in the EOG signal. Noise attenuation and signal separation have received special attention in the EOG research. In this paper, we introduce a novel Linear-nonlinear combinational filter based on weighted FIR-median-hybrid (WFMH) with the characteristic of the EOG signal. The result of the simulation shows that this filter has the property of removing random noise more efficiently when preserving sharp edges. Finally, it is shown that the new filter is effective in separating saccadic and eye blink in the EOG signal.
Electrooculography ; methods ; Eye Movements ; physiology ; Humans ; Signal Processing, Computer-Assisted