• Annals of Clinical Neurophysiology
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• v.1 no.2
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• pp.173-181
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• 1999

Eye movements serve vision by placing the image of an object on the fovea of each retina, and by preventing slippage of images on the retina. The brain employs two modes of ocular motor control, fast eye movements (saccades) and smooth eye movements. Saccades bring the fovea to a target, and smooth eye movements prevent retinal image slip. Smooth eye movements comprise smooth pursuit, the optokinetic reflex, the vestibulo-ocular reflex (VOR), vergence, and fixation. Saccades achieve rapid refixation of targets that fall on the extrafoveal retina by moving the eyes at peak velocities that can exceed $700^{\circ}/s$. Various brain lesions can affect saccadic latency, velocity, or accuracy. Smooth pursuit maintains fixation of a slowly moving target. The pursuit system responds to slippage of an image near the fovea in order to accelerate the eyes to a velocity that matches that of the target. When smooth eye movements velocity fails to match target velocity, catch-up saccades are used to compensate for limited smooth pursuit velocities. The VOR subserves vision by generating conjugate eye movements that are equal and opposite to head movements. If the VOR gain (the ratio of eye velocity to head velocity) is too high or too low, the target image is off the fovea, and head motion causes oscillopsia, an illusory to-and-fro movement of the environment.

• YAKHAK HOEJI
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• v.38 no.5
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• pp.562-567
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• 1994

Now para-phenylenediamine(PPDA) is generally used as component of most hairdyes because it can be used more conveniently and effectively than the others. But PPDA become known to cause side effects such as skin sensitization, contact dermatitis and eye irritation. So this study was done to restudy the safety of hairdyes containing PPDA. The results of experiment were as follows. 1. As a result of primary skin irritation test and eye irritation test in white rabbits, the solution containing 5% PPDA(in saline) were classified as weak irritant but four kinds of commercial hairdyes containing PPDA were proved not to have any irritation. 2. As a result of skin sensitization test in guinea pig, four kinds of commercial hairdyes were classified as Calss I(week irritant) but three kinds of commercial hairdyes induced skin sensitization for guinea pig to 5% in test groups. These results indicate that the actual toxicity of commercial hairdyes(four kinds) is negligible. But based on the results of experiment, it is thought that there is possibility of some commercial hairdyes to induce skin sensititization.

• Journal of Radiation Protection and Research
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• v.47 no.1
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• pp.39-49
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• 2022

Background: For proper monitoring of the eye lens dose, an appropriate calibration factor of a dosimeter and information about the mean energies of X-rays are indispensable. The scattered X-ray energy spectra should be well characterized in medical practices where eye lenses of medical staffs might be high. Materials and Methods: Scattered X-ray energy spectra were experimentally derived for three different types of X-ray diagnostic and therapeutic equipment, i.e., the computed tomography (CT) scan, the angiography and the fluoroscopy. A commercially available CdZnTe (CZT) spectrometer with a lead collimator was employed for the measurement of scattered X-rays, which was performed in the usual manner. Results and Discussion: From the obtained energy spectra, the mean energies of the scattered X-rays lied between 40 and 60 keV. This also agreed with that obtained by the conventional half value layer method. Conclusion: The scattered X-rays to which medical workers may be exposed in the region around the eyes were characterized by means of spectrometry. The obtained mean energies of the scattered X-rays were found to match the flat region of the dosimeter response.

• Journal of the Korean Society of School Health
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• v.31 no.3
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• pp.178-185
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• 2018

Purpose: This study aims to examine the effects of auriculotherapy on reducing signs of dry eye syndrome. Methods: This study is based on a pretest-posttest nonequivalent control group design. The participants who scored higher than 13 on the Ocular Surface Disease Index (OSDI) were divided randomly into two groups, the experimental group (n=45) and the control group (n=44). Auriculotherapy was performed by researchers for 2 weeks. For the experimental group, seed stickers were applied to the eye, liver, shenmen, and tubercle point of their ears. The pretest and the posttest included the same questionnaires of the OSDI as well as the Visual Function Questionnaire (NEI-VFQ25) and the eye fatigue. Data were analyzed by descriptive statistics, $x^2$ test, t-test and paired t-test, using SAS 20.0 program. Results: The difference in the OSDI's scores showed a significant decrease between the pretest and the posttest (t=-4.12, p<.001) in the experimental group. No significant difference was found in the NEI-VFQ25 (t=-0.10, p=.921, t=-0.91 p=.374). However, the experimental group showed a significant decrease in eye fatigue (t=5.78, p<.001), whereas the control group showed no difference (t=1.38, p=.18). Conclusion: Auriculotherapy can be used effectively on relieving the symptoms of dry eye syndrome and eye fatigue. However, the quality of life related to eyes was not improved by auriculotherapy.

• Journal of Korean Clinical Health Science
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• v.11 no.1
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• pp.1632-1638
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• 2023

Purpose: The aim of this study was to determine the distribution of the cornea thickness and intra ocular pressure Korean adult of 20 to 24 year old using the Pentacam and tonometer. Methods: The subjects of this study were 43 Korean adults with healthy eyes. Corneal thickness was measured with Pentacam device. The intra ocular pressure was measured with tonometer. Data was analyzed by means of the Pearson's correlation cofficient. P-values<0.001 were considered statistically significant. Results: Mean age of subjects was 20.41±0.86 years. The mean +/- intra ocular pressure of the right eye and left eye were 16.236±2.523mmHg and 16.971±1.992mmHg, respectively. The mean central corneal thickness of the right eye and left eye was 545.324±38.682㎛ and 547.442±33.778㎛, respectively. No significant difference in central corneal thickness was found between the right and left eyes. But, there was a statistically significant difference between central cornea thickness and peripheral cornea thickness around 4 mm of central cornea(p<0.001, Pearson's correlation). However there was no statistically significant difference between central cornea thickness and intra ocular pressure. Conclusion: The results of this study could be used as a clinical reference data for diagnosis and treatment of cornea in Korean adult.

• Restorative Dentistry and Endodontics
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• v.48 no.4
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• pp.40.1-40.8
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• 2023

Objectives: The purpose of this study was to evaluate the influence of eye dominance on color perception, and shade matching. Materials and Methods: A total of 104 participants were selected for the study. There were 3 groups: Group I: 3rd and 4th year dental students and interns (n = 40); Group II: postgraduates (n = 34); Group III: senior residents and faculty members (≥ 6 years of clinical experience) (n = 30). All participants were evaluated for congenital color blindness with Ishihara plates, their dominant eye with Mile's test, and their color perception with the Farnsworth-Munsell 100 hue test. The shade guide test was used for shade matching with a second corresponding set of Vitapan classical shade guides. Results: The results of Mile's test revealed that 60.6% were right-eye dominant and 39.4% were left-eye dominant. There was a statistically significant difference among all participants between the dominant eye and the non-dominant eye in shade matching. Conclusions: The dominant eye has a positive effect on shade matching and the ability to match shades becomes better with an increase in clinical experience.

• Journal of Korean Clinical Health Science
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• v.2 no.4
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• pp.223-230
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• 2014

Purpose. Scheduled calibration of refractive error's have various refractive surgery, and a side effect of post refractive surgery for refractive errors's before refractive surgery, by analyzing the eye condition of the refractive error's good state, it tries to increase the satisfaction of refractive error's refractive surgery. Methods. In response to 60 people preoperative data 20-30 generations of age, were analyzed for eye conditions. Results. IOP, thickness of the cornea, liquid leakage amount inspection, the corneal endothelium inspection, the size of the pupil, have been conducted auto refraction test and showed a numerical value in most normal range. Conclusion. Surgery can be of individual differences of patients, it is difficult to define the full normal range, to the surgery based on the case of this study, the side effects of patients after surgery is expected to be prevention.

• Journal of Environmental Health Sciences
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• v.41 no.6
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• pp.412-424
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• 2015

Objectives: An ultra dry air environment of nearly ${\leq}2%$ RH is often required in lithium battery factories. The objective of this study is to evaluate the subjective eye, pulmonary, nose, and skin symptoms of workers exposed to ultra-low relative humidity and thionyl chloride. Methods: We recruited 274 workers using a self-reported questionnaire in March 2014. Those who worked in ultra-low relative humidity and with thionyl chloride were identified and their prevalence of symptoms was compared with that of other workers. We excluded white collar workers, researchers and other workers who were exposed to various hazard factors, and finally included 164 workers. Results: There were significant differences in the rate of self-reported eye and skin symptoms between exposure group_1 and exposure group_2. Exposure group_2 experienced more frequent eye, and skin symptoms. Multinomial logistic regression analysis for experience of dry eye symptoms and skin symptoms in exposure group_2 showed that dry eye symptoms (odds ratio [OR], 6.33, 95% confidence interval [CI], 2.19-18.24, p<0.001), and itchiness (OR, 6.45, 95% CI, 1.94-21.43, p<0.01) were the significant variables. The complaints of workers experiencing ultra-low relative humidity and thionyl chloride were high compared with other workers. Conclusion: These findings suggest that exposure to ultra-low relative humidity and thionyl chloride may be associated with more frequent eye and skin symptoms than exposure to ultra-low relative humidity alone. The current precautions to protect workers from the adverse effects of ultra-low relative humidity and thionyl chloride appear to be insufficient, indicating that additional management plans to reduce symptoms should be considered.

• Journal of Environmental Health Sciences
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• v.38 no.4
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• pp.340-350
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• 2012

Objectives: This study was conducted to investigate skin and eye symptoms according to swimming pool user characteristics and chlorine concentration at indoor swimming pools in the Daegu region. Methods: A total of 296 swimming pool users were enrolled from the eight swimming pools randomly chosen in Daegu. Each user completed a self-administered questionnaire with general, swimming related, and symptoms suffered throughout December 2008 to August 2009. The water analysis of swimming pools was substituted with the swimming pool water analysis practiced by district offices to 2008. Results: There were significant differences in experience rate of self-reported skin and eye symptoms between coaches and students except dander. The users of swimming pools having higher chlorine concentrations suffered from more frequent skin and eye symptoms. The results of multiple logistic regression analysis for experience of skin symptoms showed that coaches (OR = 6.81, 95% CI: 2.46~18.81) and pools with chlorine concentrations over 0.4 mg/l (OR = 1.75, 95% CI: 1.01~3.03) were the significant variables. For experience of eye symptoms, coaches (OR = 4.13, 95% CI: 1.25~13.69) at a swimming pool was the significant variable. Conclusions: Increased exposure to swimming pool water and exposure to swimming pool showed that higher chlorine concentration may cause more frequent skin and eye symptoms.

• Journal of the Korean Society of Radiology
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• v.9 no.5
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• pp.279-285
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• 2015

The eye of human is a radiation sensitive organ and this organ should be shielded from radiation exposure during brain CT procedures. In the brain CT procedures, bismuth protector using to reduce the radiation exposure dose for eye. But protecting the bismuth always accompanies problem of the image quality reduction including artifact. This study aim is the eye radiation exposure dose and image quality evaluation of the new tube current modulation such as new organ based-tube current modulation, longitudinal-TCM, angular-TCM between shielding scan technique using bismuth and lead glasses. As a result, radiation dose of eye is reduced 25.88% in new OB TCM technique then reference scan technique and SNR new OB TCM is 6.05 higher than bismuth shielding scan technique and lower than reference scan technique. In clinical brain CT, new OB TCM technique will contribute to reduction of radiation dose for eye without decrease of image quality.