1.A Study on the Spectacles-wearing in Korea.
Seung Hum YU ; Yong Ho LEE ; Woo Hyum CHO
Korean Journal of Preventive Medicine 1987;20(1):120-128
To assess the proportion of spectacles-wearing and an aspect of familial aggregation of myoptic spectacles-wearing and to observe the birth cohort for myoptic spectacles-wearing, a nationwide self-administered questionnaire survey was conducted from March 11 to September 19, 1985. A probability sample of 13,346 persons was taken from 180 enumerated districts designated by the fifth nationwide tuberculosis prevalence survey from Korean Institute of Tuberculosis. The major findings of this survey are as follows: 1) Total of 62.5% of the study population lived in urban area whereas 37.5% lived in Eup-Myun area. There was statistically significant difference in age and sex distribution between two residential area. 2) The percentage of spectacles-wearing was 8.3% and among these, myoptic and hyperoptic spectacles were 6.0%, 2.3%, respectively. A total of 8.8% of the male study population wore spectacles and this was slightly higher than the female (8.0%). 3) Among the occupational groups, students were the highest myoptic spectacles-wearing group whereas professionals were the highest hyperoptic spectacles-wearing group. 4) The proportion of myoptic spectacles-wearing was higher in female students than in male students respectively 11.6%, 8.7%. There was an increasing tendency of spectacles-wearing as age increased. 5) The age-sex adjusted prevalence rate of myoptic spectacles-wearing by residential areas was 2 times higher in urban area than Eup-Myun area. 6) A wearing of the myoptic spectacles in early age was observed in recent birth cohort than remote birth cohort. 7) There was a tendency of familial aggregation for myoptic spectacles-wearing. The proportion of myoptic spectacles-wearing was 6 times higher for those who had parents wearing spectacles. 8) 60.9% of the total myoptic spectacles-wearing persons received the eye-specialist's order and 44.9% for the hyperoptic spectacles wearing.
Cohort Studies
;
Eyeglasses
;
Female
;
Humans
;
Korea*
;
Male
;
Occupational Groups
;
Parents
;
Parturition
;
Prevalence
;
Surveys and Questionnaires
;
Sampling Studies
;
Sex Distribution
;
Tuberculosis
2.Hospital Services Utilization by Insured and Non-insured Patients for Cesarean Section in a University Hospital.
Seung Hum YU ; Woo Hyun CHO ; Dai Kyu OH
Korean Journal of Preventive Medicine 1981;14(1):53-58
In order to discover difference that may exist in quantity of medical care services, length of stay and hospital changes between insured and non-insured patients, records for primary Cesarean section patients discharged between July 1978 and June 1980 from a university hospital were examined. In addition, Cesarean section rates among the total deliveries for a two-year period between the groups were studied. The results showed that volume of services was greater and length of stay was longer among the insured, however, charges were higher among the non-insured. Cesarean section rates were statistically significantly different between insured and non-insured patients for every age group except the group of 35 or more.
Cesarean Section*
;
Female
;
Humans
;
Length of Stay
;
Pregnancy
3.The Study of Normal Visual Fields Using Goldmann Module in OCTOPUS 101 Automated Perimetery in Koreans.
Seung Chan LEE ; Seung Young YU ; Hyung Woo KWAK
Journal of the Korean Ophthalmological Society 2004;45(7):1123-1127
PURPOSE: Kinetic automated perimetric tests were performed with OCTOPUS 101 perimeter using Goldmann module. Normal isopter positions in the peripheral visual field were visualized by the average position +/- 2 standard deviations. METHODS: We examined 102 eyes of 51 normal healthy Koreans who had no family history of glaucoma, no specific ophthalmologic disease, best corrected visual acuity more than 1.0 and normal intraocular pressure less than 21 mmHg with OCTOPUS 101 perimeter using Goldmann module in 5 isopters (I1e, I2e, I3e, I4e, II4e) at 8 meridians (0degree, 45degrees, 90degrees, 135degrees, 180degrees, 225degrees, 270degrees, 315degrees). RESULTS: The visual field was oval shape, and widest at the inferotemporal area, followed by temporal, and inferior. CONCLUSIONS: The normal position of 4 isopters can be used as a reference index for the peripheral visual field test.
Glaucoma
;
Humans
;
Intraocular Pressure
;
Meridians
;
Octopodiformes*
;
Visual Acuity
;
Visual Field Tests
;
Visual Fields*
;
Vitelliform Macular Dystrophy
4.Clinical Usefulness of Infrared image for Subretinal Structure in Chorioretinal Disease.
Seung Joon LEE ; Seung Young YU ; Hyung Woo KWAK
Journal of the Korean Ophthalmological Society 2002;43(3):478-491
PURPOSE: Scanning laser ophthalmoscope (SLO) has improved Infrared (IR) imaging. Since greater penetration of IR light permitted better visualization of subretinal structures, we evaluated chorioretinal layer in various chorioretinal dieases with SLO. METHODS: Cases of central serous chorioretinopathy (CSC), drusen, age-related macular degeneration (AMD), Vogt-Koyanagi-Harada disease, MEWDS (multiple evanesant white dot syndrome) and inflammatory choroiditis, toxoplasmosis, Stargardt's disease, proliferative diabetic retinopathy (PDR) and submacular hemorrhage were included. We used SLO (101, Rodenstock, Germany) for IR image and compared argon laser image with monochromatic IR image (780 nm wave length). RESULTS: The demarcation and extent of serous retinal detachment and macular star were more distinct in IR image. Small drusen, subretinal deposit and RPE atropy which could not be seen in argon green laser image were visible and appeared brightly with high reflectance in IR image. The CNV membrane which was not seen in full extent in argon laser image were observed completely in IR image. In case of inflammatory choroiditis, patch-like hot spot with surrounding high reflectance was observed in IR image. The subretinal structures and new vessels were clearly visible in IR image despite overlying thick preretinal fibrous prolifertive membrane and vitreous hemorrhage. CONCLUSIONS: The IR image using SLO is a fast and non-invasive diagnostic tool. Compared to fluorescein angiography, IR image gave a improved image for subretinal structure and additional information. Therefore IR imaging is recommended along with clinical symptom, FAG, ICGA for the diagnosis and treatment.
Argon
;
Central Serous Chorioretinopathy
;
Choroid
;
Choroiditis
;
Diabetic Retinopathy
;
Diagnosis
;
Fluorescein Angiography
;
Hemorrhage
;
Macular Degeneration
;
Membranes
;
Ophthalmoscopes
;
Retina
;
Retinal Detachment
;
Toxoplasmosis
;
Uveomeningoencephalitic Syndrome
;
Vitreous Hemorrhage
5.First-finder-related Clinical Features of Intermittent Exotropia
Chung Woon KIM ; Seung Woo KIM ; Jaeeun YU ; Seung Ah CHUNG
Journal of the Korean Ophthalmological Society 2022;63(11):928-934
Purpose:
To determine whether the clinical features of intermittent exotropia (IXT) needing muscle surgery were different in the ophthalmologist-detected and non-specialist-detected groups (including parents).
Methods:
Medical records of 218 children (mean age: 5.9 ± 1.4 years) with IXT of ≥ 20 prism diopters (PD) were reviewed retrospectively. The angles of deviation were measured using the prism and alternate cover test and assessed by two ophthalmologists using photographs with a translucent occluder (photographic angle). The IXT subtype, fusional control, stereopsis, suppression, and spherical equivalent (SE) were compared between the ophthalmologist-detected and non-specialist-detected groups.
Results:
Mean 25.8 ± 6.8 PD of distant angle of IXT was first detected by the ophthalmologist in 41 patients (18.8%) and the non-specialists in 177 patients (81.2%). The deviated eye was more myopic in the ophthalmologist-detected than non-specialist- detected group (-0.77 ± 1.59 diopters [D] vs. -0.19 ± 1.48 D, p = 0.03). There were no other differences between the two groups. A comparison of 39 age- and non-dominant eye SE-matched pairs demonstrated that the measured angles for distant and near fixation were smaller in the ophthalmologist-detected than non-specialist-detected group (24.0 ± 6.8 PD vs. 28.5 ± 6.4 PD and 26.9 ± 6.6 PD vs. 31.0 ± 6.4 PD, respectively, p < 0.01), while the remaining characteristics, including the photographic angle, were similar.
Conclusions
In cases with small angles of deviation or myopia, IXT with angles requiring surgical correction were commonly first detected by ophthalmologists during examinations.
6.Comparision of the Effects of Transpupillary Thermotherapy(TTT) of Pigmented and Albino Rabbit Retina.
Tae Kwann PARK ; Seung Young YU ; Hyung Woo KWAK
Journal of the Korean Ophthalmological Society 2001;42(5):762-771
PURPOSE: We compared the clinicopathologic effects of TTT between pigmented and albino rabbits. METHODS: TTT was delivered using infrared diode laser at 810 nm(Iris Medical Instrument, Mountain Veiw, CA, USA) and applied with spot size of 3 mm, duration of 60 seconds. At 1 week and 4 weeks after TTT, fundus photographs and simultaneous FAG/ICG angiogram were taken with SLO(Scanning Laser Ophthalmolscopy, Rodenstock, Munish, Germany). Light and electron microscopic examination were performed. RESULTS: In pigmented rabbits, visible funduscopic change was visible even with minimal power setting(100 mW). Obliteration of choroidal vessels was observed on ICG angiogram. In microscopic examination, entire layers of neural retina, retinal pigment epithelial cells, and deep choroid were severely damaged at the center of treated fields. Whereas, in albino rabbits fundus changes were not observed at any power setting. However, focal thrombosis at margin of lesion was identified on ICG angiogram after power of 300 mW. In microscopic examination, tissue damage was developed up to 600 mW and the lesion extended into the superficial choroid posteriorly and outer neural retina anterioly. CONCLUSIONS: The effect of TTT was increased with fundus pigmentation. Clinically we should adjust TTT power setting according to the amount of melanin pigmentation in the fundus.
Choroid
;
Epithelial Cells
;
Lasers, Semiconductor
;
Melanins
;
Pigmentation
;
Rabbits
;
Retina*
;
Retinaldehyde
;
Thrombosis
7.Projection of Physician Manpower Supply in Korea.
Seung Hum YU ; Woo Hyun CHO ; Yong Ho LEE ; Byung Yool CHEON
Korean Journal of Preventive Medicine 1988;21(1):61-69
In this study, the number of physicians presently living in Korea thoroughly estimated by several means and, on this bases, their productivity and level of supply were estimated. The results were as follows : First, the number of physicians who did not notify the Korea Medical Association in May 1987 were 10,110, including 4,093 emigrant physicians(40.5%), 861 military medical officers, 745 public health doctors, and 107 decreased physicians. A total of 1,330 physicians could not be identified by any effort. Second, among the 34,897 registered physicians as of May 1987, 29,933(85.8%) were residing in Korea, 4,115 physicians(11.8%) had emigrated to other countries, and 849 physicians(2.4%) were decreased. Practicing physicians defined as those in Korea who were not retired, serving in the military, or completing residencies or internships, comprised 78.6%(27,414 physicians) of the total number of registered physicians. Third, it is estimated that in the year 2000 the number of registered physicians, physicians residing in Korea, and practicing physician will be 75,040, 64,038 and 57,655, respectively and these are increases of 115.0%, 113,9%, and 110.3%, respectively, compared to 1987. Fourth, the population physician ratio will be 759 to one physician in the year 2000. Fifth, the productivity of physicians, as calculated by relative values defining the productivity of 35 to 44 year-old male physicians as 10, will increase 110.7% in the year 2000 compare to that of 1987, and this increment is almost the same level as that of physicians supply. From the results of the present analysis of physicians manpower and supply projection, it can be recognized that the development of a regular notification system is necessary in order to identify precisely the number of physicians. Also a policy a physician supply is essential in order to adjust in advance the number of physicians, otherwise there will be surplus to the medical demand.
Adult
;
Efficiency
;
Emigrants and Immigrants
;
Humans
;
Internship and Residency
;
Korea*
;
Male
;
Military Personnel
;
Public Health
8.The significance of corpus callosal size in the estimation of neurologically abnormal infants.
Korean Journal of Pediatrics 2008;51(11):1205-1210
PURPOSE: The development of the corpus callosum occupies the entire period of cerebral formation. The myelination pattern on magnetic resonance imaging (MRI) is very useful to evaluate neurologic development and to predict neurologic outcome in high risk infants. The thickness of the corpus callosum is believed to depend on the myelination process. It is possible to calculate the length and thickness of the corpus callosum on MRI. Thus, we can quantitatively evaluate the development of the corpus callosum. We investigated the clinical significance of measuring various portions of the corpus callosum in neonate with neurologic disorders such as hypoxic brain damage and seizure disorder. METHODS: Forty-two neonates were evaluated by brain MRI. We measured the size of the genu, body, transitional zone, splenium, and length of the corpus callosum. Each measurement was divided by the total length of the corpus callosum to obtain its corrected size. The ratio of corpus callosal length and the anteroposterior diameter of the brain was also measured. RESULTS: There was no statistical significance in the sample size of each part of the corpus callosum. However, the corrected size or the ratio of body of the corpus callosum correlated with periventricular leukomalacia and hypoxic ischemic encephalopathy. CONCLUSION: There was no statistical significance in the sample size of each part of the corpus callosum. However, the corrected size or the ratio of body of the corpus callosum correlated with periventricular leukomalacia and hypoxic ischemic encephalopathy.
Brain
;
Corpus Callosum
;
Epilepsy
;
Humans
;
Hypoxia, Brain
;
Hypoxia-Ischemia, Brain
;
Infant
;
Infant, Newborn
;
Leukomalacia, Periventricular
;
Magnetic Resonance Imaging
;
Myelin Sheath
;
Nervous System Diseases
;
Sample Size
9.Health Care Utilization and Its Determinants among Island Inhabitants.
Seung Hum YU ; Woo Hyun CHO ; Chong Yon PARK ; Myung Keun LEE
Korean Journal of Preventive Medicine 1987;20(2):287-300
Island regions suffer from a shortage of health care in part because they are less developed, they cover a widespread area relative to the population, and due to transportation barriers. The purpose of this study was to assess the level of illness and the magnitude of medical care utilization, and to investigate the determinants of utilization in these area. The data were collected by means of a household survey conducted from February 16 to 25, 1987 on 5 islands which were selected in consideration of the size of the population, the distance from the main land, and the distribution of health care facilities. The household response rate was 89.1% (491 of 551 households), and 1971 persons were surveyed. The major findings of this study are as follows: 1) The morbidity rate of the island inhabitants was 27.7% during the two weeks, and 25.5 chronic illnesses and 9.1 acute illnesses per 100 persons, were noted. Differences in the magnitude of illness were statistically significant by sex, age, education, and family size. 2) The magnitude of total ambulatory care utilization was 16.8 visits per 100 persons during the two weeks, which was less than that of other regions; and differences in the magnitude of total ambulatory care were statistically significant by sex, age, education, occupation, and family size. 3) Unmet needs were classified as 56.0% in chronic illnesses and 19.6% in acute illnesses; and differences in unmet needs were statistically significant by sex, age, education, occupation, income, and family size. 4) Statistically significant determinants in medical care utilization included the frequency of acute illness and chronic illness, and income in total utilization; the frequency of chronic illness and acute illness, and medical care insurance in physician visits. 5) According to the results of the path analysis, need factors had the greatest effect on utilization, and predisposing factors had more indirect effects through enabling or need factors than direct effects.
Ambulatory Care
;
Causality
;
Chronic Disease
;
Delivery of Health Care*
;
Education
;
Family Characteristics
;
Humans
;
Insurance
;
Islands
;
Occupations
;
Transportation
10.A Comparative Study of Two Survey Methods for Health Services Research Modified Self-administered Questionnaire vs. Interview Survey.
Seung Hum YU ; Yong Ho LEE ; Woo Hyun CHO ; Chong Yon PARK
Korean Journal of Preventive Medicine 1988;21(2):431-441
The purpose of this study was to compare the difference of two survey methods for health services research. Data were collected by means of two types of household survey conducted from March 11 to September 19, 1985. A probability sample of 30,613 persons was taken from 180 Enumerated Districts designated by the Economic Planning Board. The sample was divided into two groups systematically. One group was surveyed by the self-administered questionnaire and the other group was interviewed. Response rates were 81.4% and 90.6% respectively. The data were analyzed by the ratio of the results of the self-administered survey to those of the interview survey. No difference was observed in sex, age, residence, or occupation between the two groups. However the respondents' characteristics were statistically different between the two groups. The major findings of this study are as follows : 1. The morbidity rate was 142.5 per 1,000 persons during the two week period by the self-administered questionnaire survey and 74.3 per 1,000 persons with the interview survey method. The ratio of the morbidity rate by the self-administered questionnaire to that by the interview was 1.92, and the difference between the two rates were due to the personal characteristics. 2. The out-patient utilization rate was 10.2 visits per person per year by the self-administered questionnaire survey and 5.4 by the interview survey, and the ratio was 1.89; the admission rate was 3.2 times per 100 persons per year by the self-administered questionnaire survey and 1.9 times by the interview survey, and the ratio was 1.68. Differences due to the sociodemographic characteristics were greater in the out-patient utilization rates than in the admission rates. 3. Percentages of effective medical care demand were 90.2% in the self-administered survey and 92.3% in the interview survey; the ratio was 0.98 which was less than that of the morbidity rate and medical care utilization. But, differences of effective medical care demand occurred in persons with no occupation, and aged or low educated respondents. 4. Respiratory illness had the highest frequency in the two survey methods. But there was a slight difference between the two survey methods in morbidity composition. 5. It was concluded that data collected by the interview survey were inclined to be underestimated and this problem can be corrected by a modified self-administered survey.
Surveys and Questionnaires*
;
Family Characteristics
;
Health Services Research*
;
Health Services*
;
Humans
;
Occupations
;
Outpatients
;
Surveys and Questionnaires*
;
Sampling Studies