1.Evaluation of Retinal Visual Acuity Using SLO in Young Healthy Volunteers.
Seung Young YU ; Hyung Woo KWAK ; Jae Myung KIM
Journal of the Korean Ophthalmological Society 1999;40(6):1599-1605
We have attempted to measure parafoveal retinal acuity directly on the exact retinal locus, while observing the retinal image in real time using the scanning laser ophthalmoscope(SLO 101, Rodenstock, Munish, Germany). By the SLO Visumetry software(Rodenstock v. 3.0), thirty eyes of healthy volunteers were examined in 20degrees image field. Using Snellen E as stimulus, the examination was performed from the fovea by the radial pattern. The maximal retinal distance point, which responded to stimulus, was recorded by the pixel, and the distance(mm) from the fovea was calculated by the Bennett formula. The maximum distance from the fovea at the given stimulus size was achieved as follows: 0.32+/-0.01mmat the 15 x15 arc of minute(0.333), 0.63+/-0.01mm at the 17 x17 arc of minute(0.294), 1.05+/-0.03 mmat 20 x 20 arc of minute(0.25), and 1.44+/-0.0 5 mmat the 23 x23 arc of minute(0.217). It was also revealed that the horizontal maximal distance from fovea at given stimulus size was statistically superior to the vertical maximal distance(p<0.05). In conclusion we were able to establish the normal range of parafoveal retinal acuity in healthy volunteers. It may serve as the baseline for subsequent study of retinal pathology and functional evaluation as well as its treatment.
Healthy Volunteers*
;
Pathology
;
Reference Values
;
Retinaldehyde*
;
Visual Acuity*
2.The Diagnostic Value of Isocapnic Hyperventilation of Cold Air in Adults with Suspected Asthma.
Jae Hwa CHO ; Jwong Swon RYU ; Ji Young LEE ; Seung Min KWAK ; Hong Lyeol LEE ; Chul Ho CHO
Tuberculosis and Respiratory Diseases 2001;51(3):232-239
BACKGROUND: Asthmatic patients frequently suffer cold-weather-associated respiratory symptoms. The sensitivity, specificity, accuracy and diagnostic value of isocapnic hyperventilation of cold air(IHCA) using a multistep method was investigated in patients suspected to have asthma. METHOD: One hundred and 29 adult patients who had an IHCA performed between july 1999 and December 2000, had an methacholine bronchoprovocation test because of a clinical suspicion of asthma. RESULTS: According to strict criteria, 50 were defined as asthmatics and 79 as symptomatic nonashmatics. There were no differences in age, sex and smoking state between the asthmatic and symptomatic nonasthmatic groups. There was a significant decrease in the percentage reduction in the forced expiratory volume in 1 second(FEV1) after the IHCA between the asthmatics(-10.0±6.8%) and the symptomatic nonasthmatics(-2.3±2.5%). The factors associated with a reactivity to IHCA were FEV1/FVC, FEF25-75/FVC and FEV1(% of predicted). The accuracy was highest using a 7% fall in FEV1; the sensitivity was 76% and the specificity 96%. CONCLUSION: IHCA is a specific, although not a sensitive, test for diagnosing asthma in adult patients. Furthermore, the diagnostic cut-off value of the different methods of IHCA need to be determined.
Adult*
;
Asthma*
;
Forced Expiratory Volume
;
Humans
;
Hyperventilation*
;
Methacholine Chloride
;
Sensitivity and Specificity
;
Smoke
;
Smoking
3.Preferential Hyperacuity Perimeter (PHP) in Myopic CNV.
Jae Ho SHIN ; Seung Young YU ; Hyung Woo KWAK
Journal of the Korean Ophthalmological Society 2007;48(3):376-384
PURPOSE: To analyze the hyperacuity defects of preferential hyperacuity perimeter (PHP) in myopic CNV and correlate with the other macular anatomical or physiological properties obtained with fluorescein angiography (FA), Optical coherence Tomography (OCT), and central perimeter. METHODS: Seven patients with myopic CNV diagnosed by FA underwent PHP, OCT, central visual field (VF). We examined the locational correlation among FA, central VF and PHP hyperacuity defect and then compared PHP hyperacuity defect with the CNV size by OCT. Also we made a comparison with macular sensitivity change in VF and hyperacuity defects change in PHP after PDT in 4 patients. RESULTS: All the 7 eyes with myopic CNV tested positive for hyperacuity defects. 5 eyes showed locational correlation among PHP and FA, central VF. The size of hyperacuity defect of PHP and CNV size by OCT was positive correlation (p=0.007). Four eyes treated with PDT showed decrease of PHP hyperacuity defect size and changes in location according to decrease of CNV size after PDT. CONCLUSIONS: Our results suggest that the PHP may be used to detect myopic CNV and beneficial for analyzing functional effect following PDT in myopic CNV patients. These results require further validation in a larger population.
Fluorescein Angiography
;
Humans
;
Photochemotherapy
;
Tomography, Optical Coherence
;
Visual Fields
4.Prediction Formulas of Pulmonary Function Parameters Derived from the Forced Expiratory Spirogram for Healthy Nonsmoking and Smoking Adults and Effect of Smoking on Pulmonary Function Parameters.
Won Kyoung CHO ; Eun Ok KIM ; Seung Jae MYUNG ; Seung Min KWAK ; Youn Suck KOH ; Woo Sung KIM ; Won Dong KIM ; Moo Song LEE
Tuberculosis and Respiratory Diseases 1994;41(5):521-530
BACKGROUND: The past. studies on prediction formulas of pulmonary function parameters in healthy nonsmoking Korean adults have been performed in relatively small number of subjects and the reported results were restricted on a few parameters. Also there was no systematic investigation into the effect of smoking on pulmonary function parameters in smokers who have no respiratory symptoms. Therefore we attempted to establish prediction formulas of pulmonary function parameters and examined the effect of smoking on pulmonary function parameters. METHODS: We analyzed the result of parameters derived from the forced expiratory spirogram in 1,067 nonsmoking subjects from June in 1990 to December in 1991. They consisted of 306 males and 761 females and had neither respiratory symptoms nor history of respiratory disease. We derived prediction formulas by multiple linear regression method from their age, heights, and weights in each sex. To examine the effect of smoking on pulmonary function parameters, we classified 383 smoking men into three groups according to the past amount of smoking as follows : i.e. group of smokers who have smoked below 10 pack-years, 10-20 pack-years and above 20 pack-years. Regarding each group of past smoking as an independent dummy variable, we analyzed pulmonary function parameters including nonsmoking men as a baseline by multiple linear regression. We evaluated the smoking effect on pulmonary function parameters according to estimated p-value. RESULT: 1) Prediction formulas for pulmonary function parameters in each sex were derived. 2) The past smoking less than 10 pack-years does not give any effect on pulmonary function parameters. The past smoking of 10~20 pack-years showed significant negative correlation with FEV1/FVC and FEF 25~75%, and the smoking above 20 pack years showed negative correlation with FEV1 and FEV1/FVC. CONCLUSION: We have got prediction formulas of pulmonary function parameters which is driven from forced expiratory spirogram in nonsmoking Korean adults by multiple linear regression from age, heights and weights of subjects. The past smoking more than 10 pack-years showed negative correlation with some pulmonary function parameters of airflow obstruction.
Adult*
;
Female
;
Humans
;
Linear Models
;
Male
;
Smoke*
;
Smoking*
;
Weights and Measures
5.Massive Hemoptysis after Generalized Tonic Clonic Seizure Requiring Mechanical Ventilation.
Jeong Seon RYU ; Jae Hwa CHO ; Seung Min KWAK ; Hong Lyeol LEE ; Il Keun LEE
Yonsei Medical Journal 2002;43(4):543-546
A 38-year-old woman presented with massive hemoptysis ( 200 mL/ 24 hours) occurring abruptly after generalized tonic clonic seizure. She experienced similar episodes of hemoptysis on three later occasions. Although the coexistence of hemoptysis and seizure has been reported, albeit rarely, as a clinical manifestation of postictal neurogenic pulmonary edema, massive hemoptysis after seizure is an extremely rare event with no recurrent cases of such episodes having ever been reported. The coexistence of hemoptysis and seizure increases the difficulty in diagnosis for the clinician. We describe the differential diagnosis among the diseases capable of causing seizure and hemoptysis.
Adult
;
Case Report
;
Diagnosis, Differential
;
Epilepsy, Tonic-Clonic/*complications
;
Female
;
Hemoptysis/*diagnosis/etiology
;
Human
;
Pulmonary Alveoli
;
Pulmonary Edema/complications
;
Recurrence
;
*Respiration, Artificial
6.A Validation and Reliability Study of the Korean Version of National Eye Institute Visual Function Questionnaire 25.
Jang Won HEO ; Hee Seong YOON ; Jae Pil SHIN ; Sang Woong MOON ; Hee Seung CHIN ; Hyung Woo KWAK
Journal of the Korean Ophthalmological Society 2010;51(10):1354-1367
PURPOSE: To translate and evaluate the reliability and validity of the Korean version of the National Eye Institute Visual Functioning Questionnaire-25 (NEI-VFQ-25). METHODS: Two bilingual ophthalmologists independently translated the original English version of the NEI-VFQ-25 into written Korean. A panel of the Korean Retina Society reviewed the translations to form a single reconciled forward translation of the Korean version of the NEI-VFQ-25. Another ophthalmologist back-translated this first draft into English. Both the first draft and back-translated draft were edited by a professional translator. To evaluate the correlation and validity, results between the original NEI-VFQ-25 and the Korean version, completed by the bilingual participants, were compared. RESULTS: The Korean version of the National Eye Institute Visual Functioning Questionnaire-25 was developed by translation, back-translation, and expert supervision. Results from 23 bilingual participants between the original NEI-VFQ-25 and the Korean version were compared and showed statistically significant correlation, with a Spearman's correlation coefficient of 0.4 or greater. The Kolmogorov-Smirnov test results showed no statistically significant differences between the two questionnaires. CONCLUSIONS: Translation and validation of the Korean version of the NEI-VFQ-25 was achieved.
National Eye Institute (U.S.)
;
Organization and Administration
;
Surveys and Questionnaires
;
Reproducibility of Results
;
Retina
;
Translations
7.The Effect of Glucose on Anoxia-induced Cell Damage in the Cultured Human Retinal Pigment Epithelial (RPE) Cell.
Seung Young YU ; Dae Ho KIM ; Jae Myung KIM ; Hyung Woo KWAK
Journal of the Korean Ophthalmological Society 2002;43(4):764-774
PURPOSE: It is difficult to make the standard ischemic RPE culture model which is still not established. In ischemic model, oxygen and glucose are very important. To improve experimental model, we evaluate the effect of glucose on anoxia-induced human RPE cell damage. METHODS: Human RPE cells were incubated with 95% N2/5% CO2 and standard conditions (95% air/5% CO2) at 37degrees C, and various concentation of glucose were added to a glucose-free medium : no glucose, 0.2 mg/ml, 0.4 mg/ml, -2.0 mg/ml. On a daily basis, morphological and proliferation analysis was conducted using the inverted phase contrast microscope. The extent of cell damage was estimated through cell viability analysis. Cell viability was examined using PMS(phenazinemethosulphate)-MTS(3-(4.5 -dimethyl-thiazol-2-yl)-5-(3-caboxymethoxyphenyl)-2-(4-sulfo phenyl)-2H-tetrazolium, inner salt)assay after 24, 48, 72, and 96 hours. Single-stranded DNAs were detected with monoclonal antibody to prove cell apoptosis in cell damage. RESULTS: At slightly low glucose concentration(0.4 mg/ml), the cell viability of human RPE cells cultured at room air was maintained up to 96 hours, whereas that cultured at 95% N2 decreased after 48 hours. At the anoxic condition. the cell viability of human RPE cells cultured with the low glucose concentration (0.2 mg/ml) decreased after 24 hours, but those done with higher glucose concentrations (more than 0.8 mg/ml) were maintained up to 96 hours. In the cell death caused by the anoxic culture, apoptosis was not suggested by single-stranded DNA detection. CONCLUSIONS: Properly higher glucose concentration on culture medium improve cell viability and reduce the cell damage in human RPE culture in anoxic condition. This result helps to improve experimental ischemic model of RPE cell.
Anoxia
;
Apoptosis
;
Cell Death
;
Cell Survival
;
DNA, Single-Stranded
;
Glucose*
;
Humans*
;
Models, Theoretical
;
Oxygen
;
Retinaldehyde*
8.The Effect of Intravitreal Triamcinolone Acetonide Second Injection for Diabetic Macular Edema.
Hui Jae LEE ; Dong Hee KIM ; Seung Young YU ; Hyung Woo KWAK
Journal of the Korean Ophthalmological Society 2005;46(6):976-981
PURPOSE: To evaluate the outcome of a second intravitreal injection of triamcinolone acetonide for the treatment of diabetic macular edema. METHODS: This clinical series study was carried out on 12 eyes with diabetic macular edema. All patients had shown VA (visual acuity) improvement after the first intravitreal injection of triamcinolone acetonide (4 mg). Following the exhibition of decreased VA and increased foveal thickness, the eyes received a second intravitreal injection. We analyzed the visual acuity and foveal thickness at post-treatment 1, 3, and 6 months by ETDRS (LogMar) and optical coherence tomography (OCT). RESULTS: The mean improvement of visual acuity was 0.24, 0.11, and 0.00 at the 1-, 3-, and 6-month follow-up after the first injection, and was 0.09, 0.00, and -0.20 at the 1-, 3-, 6-month follow-up after the second injection. The mean decrease of foveal thickness was 400, 243, and 109 micrometer at the 1-, 3-, 6-month follow-up after the first injection and 298, 78, and -53 micrometer at the 1-, 3-, and 6-month follow-up after the second injection. The differences of change in foveal thickness after the first and second injections were significant (P=0.02, 0.04, 0.02) but the differences of change in visual acuity were not significant (P=0.14, 0.41, 0.28). CONCLUSIONS: Intravitreal injection of 4 mg of triamcinolone acetonide may increase the visual acuity and may decrease the foveal thickness in the short term, postoperative period, but the second intravitreal injection was less effective than the first injection.
Follow-Up Studies
;
Humans
;
Intravitreal Injections
;
Macular Edema*
;
Postoperative Period
;
Tomography, Optical Coherence
;
Triamcinolone Acetonide*
;
Triamcinolone*
;
Visual Acuity
9.A Case of Otogenic Brain Abscess Causing Loss of Consciousness.
Min Kyu KWAK ; Jae Ho CHUNG ; Seung Hwan LEE ; Chul Won PARK
Korean Journal of Audiology 2014;18(2):76-79
Acute or chronic otitis media can cause intracranial complications, one of the most serious being brain abscess. Empirical antibiotic treatment and proper surgical management should be considered to avoid fatal consequences. However, proper extent and optimal timing of surgical intervention are still matters of debate. We present a case of a 31-year-old man who presented with acutely altered mental status, caused by otogenic brain abscess who we treated successfully with antibiotics and otologic surgery and no neurosurgical treatment.
Adult
;
Anti-Bacterial Agents
;
Brain Abscess*
;
Humans
;
Otitis Media
;
Unconsciousness*
10.Influence of Bile Duct Ligation on 54 Liver Regeneration in Rats.
Wook Hwan KIM ; Jae Ho LEE ; Seung Kyu JEONG ; Hye Lee PARK ; Yun Sik KWAK ; Hee Jung WANG ; Myung Wook KIM
Journal of the Korean Surgical Society 1997;52(6):785-789
N/AWe evaluate the regenerating capacity of rat liver according to the severity and duration of the obstructive jaundice. Also we evaluate the regenerating capacity of hepatectomized rat liver according to the duration of the obstructive jaundice. The 10 week-old Sprague-Dawley rats were used. Common bile duct ligation and sequential partial hepatectomies were done. The regenerating capacity was measured by tritiated thymidine incorporation into rat liver DNA. The rate of incorporation of thymidine into DNA in the jaundiced livers increased significantly compared with that in the sham-operated liver on day 3.In jaundiced rats, the regenerating capacity after partial epatectomy decreased markedly without a return toward normal on day 3 and kept low thereafter. The duration of obstructive jaundice may be a key factor in the regeneration of rat liver after partial hepatectomy.
Animals
;
Bile Ducts*
;
Bile*
;
Common Bile Duct
;
DNA
;
Hepatectomy
;
Jaundice, Obstructive
;
Ligation*
;
Liver Regeneration*
;
Liver*
;
Rats*
;
Rats, Sprague-Dawley
;
Regeneration
;
Thymidine