1.Effects of Multicurve RGP Contact Lens Use on Topographic Changes in Keratoconus.
Joon Seo HWANG ; Jin Hak LEE ; Won Ryang WEE ; Mee Kum KIM
Korean Journal of Ophthalmology 2010;24(4):201-206
PURPOSE: To evaluate the effects of wearing rigid gas permeable (RGP) contact lenses on the topographic changes in keratoconus. METHODS: Seventy-seven keratoconic eyes that wore multicurve RGP contact lenses and 30 keratoconic eyes that wore no contact lenses were retrospectively analyzed. The mean follow-ups were 22.6 and 20.5 months in the lens-wearing and control groups, respectively. Visual acuity, comfort, daily wearing time, and corneal staining were evaluated for both groups. The changes in topographic indices were compared between the lens-wearing and control groups. RESULTS: Multicurve RGP lens corrected logarithm of the minimum angle of resolution visual acuity of the lens-wearing group significantly improved from -0.016+/-0.065 to -0.032+/-0.10 at follow-up (p=0.05). In the lens-wearing group with advanced keratoconus, the Sim Kmax, Sim Kmin, apical power, astigmatic index, and anterior elevation significantly decreased from 57.68+/-4.26 diopter (D), 50.50+/-2.32 D, 62.79+/-5.11 D, 7.20+/-0.55 D and 67.36+/-16.30 microm to 55.51+/-4.28 D, 49.62+/-3.26 D, 60.31+/-5.41 D, 5.90+/-0.51 D and 60.61+/-16.09 microm, respectively (paired t-test, p<0.05). The irregularity index of 3 mm did not significantly change. Meanwhile, in the control group, the apical power and irregularity index increased from 55.56+/-7.25 D and 3.06+/-1.68 D to 57.11+/-7.75 D and 3.25+/-1.71 D, respectively (paired t-test, p=0.008, p=0.01). CONCLUSIONS: Properly fitted multicurve RGP contact lenses are not likely to contribute to the progression of keratoconus.
Adult
;
Astigmatism/etiology/pathology/therapy
;
*Contact Lenses
;
Cornea/*pathology
;
*Corneal Topography
;
Disease Progression
;
Female
;
Follow-Up Studies
;
Humans
;
Keratoconus/complications/pathology/*therapy
;
Male
;
Prognosis
;
Prosthesis Design
;
Retrospective Studies
;
Time Factors
;
Young Adult
2.Chromosome Breakage Test for the Diagnosis of Fanconi's Anemia.
Dong Wook RYANG ; Deok CHO ; Won Pyo HONG ; Hoon KOOK ; Tai Ju HWANG
Korean Journal of Clinical Pathology 1998;18(1):101-106
BACKGROUND: Fanconi's anemia (FA) is an autosomal recessive disease characterized by aplastic anemia, pre-malignancy, congenital malformations and chromosome breakage syndromes. As up to 30% of patients have no detectable congenital anomalies, the modern diagnosis of FA rests on chromosomal breakage of patient's cells induced by chemical clastogens such as diepoxybutane (DEB) or mitomycin-C (MMC). METHODS: We have done chromosome breakage test to differentiate FA from 11 aplastic anemia, three Diamond-Blackfan syndrome, three myelodysplastic syndrome, one acute leukemia with congenital anomaly and three siblings of FA. The peripheral blood lymphocytes from each individual were co-cultured in phytohemagglutinin-containing medium by the three methods, i.e., DEB treated, MMC treated and un-treated. RESULTS: Five cases were found to have increased chromosomal breakages to DEB and MMC, confirming diagnosis of FA. Other 21 cases showed no increased chromosomal breakages. No overlap was found between FA group and others (P<0.01). In one FA, there was no increased spontaneous breakage, but increased breakage to DEB and MMC. Of five FA, one case showed no congenital anomalies. CONCLUSIONS: Chromosme breakage test was shown to be simple, reliable and useful in ascertaining the diagnosis of FA.
Anemia, Aplastic
;
Chromosome Breakage*
;
Diagnosis*
;
Fanconi Anemia*
;
Humans
;
Leukemia
;
Lymphocytes
;
Mitomycin
;
Mutagens
;
Myelodysplastic Syndromes
;
Siblings
3.Neurologic complications after open-heart surgery in children.
Tae Sung KO ; Ki Joong KIM ; Dong Wook KIM ; Yong Seung HWANG ; Yong Jin KIM ; Joon Ryang RHO
Journal of the Korean Pediatric Society 1993;36(9):1245-1257
Neurologic complications after open-heart surgery are not only relatively common but also often fatal. In order to know the clinical characteristics and causative risk factors, we carried out the retrospective study on 655 patients who had been admitted and undergone OHS at Seoul National University Children's Hospital during 2-year period from July 1990 to June 1992. The results were as follows; 1) The incidence of neurologic complications after OHS was 4.7% (31 cases) of the total 655 cases. 2) In the viewpoint of the pre-op diagnosis, neurologic complications developed in 20 cases (7.8%) among cyanotic congenital heart disease and in 11 cases (2.9%J among acyanotic CHD. 3) In the viewpoint of the type of operation, the incidence of neurologic complications was 33.3% in Jatene procedure and 12.1% in Fontan procedure. 4) Compared with the group who didn't develp neurologic complications (624 cases), cardiopulmonary bypass time, aorta cross clamp time, and total arrest time were longer and the degree of hypothermia was lower in the group who had neurologic complications (31 cases), which are statistically significant each other(p<0.01). 5) In 25 cases (80.6%), neurologic complications occurred within 72 hours after OHS. 6) Clinical manifestations of neurologic complications were seizures (26 cases, 84%), consciousness change (13 cases, 42%), hemiplegia (1 case), and decreased muscle tone (1 case). 7) Of the 31 cases, 16 cases showed more than one abnormal finding among EEG, Brain CT, or Brain MRI. 8) The possible etiologies of neurologic complications were diffuse hypoxic ischemic encephalopathy (16 cases, 51.6%), focal or multiple ischemic stoke that was thought to be due to microembolisms (3 cases, 9.7%), electrolyte or acid-base imbalance (8 cases, 25.8%), and the remainders were unknown (4 cases. 12.9%) 9) In the course of neurologic complications, 11 cases (35.5%) expired, 14 cases(45.2%) recovered at discharge, 3 cases (9.7%) were controlled at discharge, and 2 cases (6.5%) had long-term sequela(one spastic quadriplegia and one hemiparesis). 10) The cause of death among mortality cases were mainly due to brain damage (7 cases), while 4 cases had other direct causes such as heart failure, respiratory failure, or sepsis.
Acid-Base Imbalance
;
Aorta
;
Brain
;
Cardiopulmonary Bypass
;
Cause of Death
;
Child*
;
Consciousness
;
Diagnosis
;
Electroencephalography
;
Fontan Procedure
;
Heart Defects, Congenital
;
Heart Failure
;
Hemiplegia
;
Humans
;
Hypothermia
;
Hypoxia-Ischemia, Brain
;
Incidence
;
Magnetic Resonance Imaging
;
Mortality
;
Muscle Hypotonia
;
Quadriplegia
;
Respiratory Insufficiency
;
Retrospective Studies
;
Risk Factors
;
Seizures
;
Seoul
;
Sepsis
4.Studies on expression of DNA topoisomerases genes and protooncogene c-Myc during hepatocarcinogenesis.
Byung Doo HWANG ; Sang Hee WON ; Ki Ryang KWON ; Kye Young KIM ; Dae Young KANG ; Sang Tae KWAK ; Kyoo LIM
Journal of the Korean Cancer Association 1993;25(5):636-650
No abstract available.
DNA Topoisomerases*
;
DNA*
5.A Case of Glanzmann's Thrombathenia.
Saeng Gu CHO ; Won Ho KANG ; Young Youn CHOI ; Tai Ju HWANG ; Dong Wook RYANG ; Joo Young YOO
Journal of the Korean Pediatric Society 1986;29(6):86-91
No abstract available.
6.Usefulness of Computerized Objective Visual Acuity Test System Using Suppression Method.
Minseop KIM ; Myung Kyoo KO ; Jeong Min HWANG ; Won Ryang WEE ; Jin Hak LEE
Journal of the Korean Ophthalmological Society 2008;49(7):1127-1134
PURPOSE: The objective visual acuity test is mandatory in certain cases, such as infants, nonverbal subjects, and subjects who need legal assistance. We designed an objective system for visual acuity test (SOVAT) consisting of three components: stimuli applied via a suppression method, display and evaluation and made a suppression method as stimuli component for SOVAT. Usefulness of the SOVAT was evaluated. METHODS: The visual stimuli were presented on a high-resolution head-mounted display (HMD). An eye movement tracking program and gaze monitoring device allowed us to monitor the patient's fixation status during the test. The suppression method, in addition to a conventional induction method, was developed to use with the SOVAT and its accuracy and confidence level were evaluated. RESULTS: On the basis of clinical data, we present the reference values for the SOVAT as below. For the induction method, objective visual acuity (smallest pixel size), the presumed subjective visual acuity was 3: 0.35-0.6, 7: 0.05-0.25, 12: below 0.05 and for the suppression method it was 1: 0.6-1.0, 1.5: 0.4-0.7, 3: 0.15-0.4, 5: 0.1-0.2. CONCLUSIONS: SOVAT using this suppression method to assess objective visual acuity proved to be more useful than that with a conventional induction method, especially in the range of high visual acuity.
Eye Movements
;
Humans
;
Infant
;
Nystagmus, Optokinetic
;
Organothiophosphorus Compounds
;
Reference Values
;
Track and Field
;
Visual Acuity
7.A Novel Computerized Visual Acuity Test for Children.
Young Joo SHIN ; In Bum LEE ; Won Ryang WEE ; Jin Hak LEE ; Jeong Min HWANG
Korean Journal of Ophthalmology 2013;27(3):194-198
PURPOSE: To investigate the efficacy of a computerized visual acuity test, the SNU visual acuity test for children. METHODS: Fifty-six children, ranging from 1 to 5 years of age, were included. In a dark room, children gazed at and followed a circular dot with 50% contrast moving at a fixed velocity of 10 pixels/sec on a computer monitor. Eye movement was captured using a charge coupled device camera and was expressed as coordinates on a graph. Movements of the eye and dot were superimposed on a graph and analyzed. Minimum visualized dot diameters were compared to the Teller visual acuity. RESULTS: Ten eyes (8.9%) of six children failed to perform the Teller visual acuity test, and two eyes (1.8%) of one patient failed to perform the SNU visual acuity test. The observed Teller visual acuity and SNU visual acuity were significantly correlated (p < 0.001). Visual angle degrees converted from the Teller visual acuity and SNU visual acuity were also significantly correlated (p < 0.001). CONCLUSION: The SNU visual acuity using moving targets correlated well with Teller visual acuity and was more applicable than the Teller acuity test. Therefore, the SNU visual acuity test has potential clinical applications for children.
Child, Preschool
;
Diagnosis, Computer-Assisted/*methods
;
Female
;
Humans
;
Infant
;
Male
;
Prospective Studies
;
Vision Disorders/*diagnosis
;
Vision Tests/*methods
;
*Visual Acuity
8.Fluorescence in situ Hybridization using Chromosome X alpha-Satellite Probe To Evaluate Engraftment and To Monitor Residual Disease after Bone Marrow Transplantation.
Dong Wook RYANG ; Deok CHO ; Won Pyo HONG ; Hyeoung Joon KIM ; Ik Joo CHUNG ; Hoon KOOK ; Tai Ju HWANG
Korean Journal of Clinical Pathology 1998;18(1):7-13
BACKGROUND: Several methods have been used to evaluate the engraftment and to monitor residual disease after bone marrow transplantation (BMT). Among them, karyotyping have been useful in gauging engraftment following opposite sex BMT. More recently, fluorescence in situ hybridization (FISH) has also been applied to determine engraftment and residual status. In order to establish the utility of this method in clinical practice, we have evaluated the data from FISH and several methods. METHODS: We performed FISH using chromosome X alpha-satellite probe (Oncor , USA) on twenty eight peripheral blood and nine bone marrow nuclear cells from eleven patients who underwent sex mis-matched transplant and from a patient who had a loss of X chromosome. RESULTS: In nine patients with well engrafted BMT, signals of host cells showed less than 5% in all patients, evaluated 21-210 days post-transplant. Mixed chimerism was detected in six patients; transiently in early post-transplant period in four, in a patient with engraftment failure, and in a patient with relapse, respectively. CONCLUSION: FISH using X probe is a rapid, quantitative and sensitive 'interphase cytogenetic method' for the evaluation of engraftment and monitoring of residual disease following sex mis-matched BMT or BMT in a patient with a loss of X chromosome; It is especially useful in early post-transplant period when ony a few cells are available during severe cytopenia.
Bone Marrow Transplantation*
;
Bone Marrow*
;
Chimerism
;
Cytogenetics
;
Fluorescence*
;
Humans
;
In Situ Hybridization*
;
Karyotyping
;
Recurrence
;
X Chromosome
9.The fetal therapy of congenital cystic adenomatoid malformation of the lung in - utero : Two cases of thoracoamniotic shunting using a basket - shaped catheter.
Joo Yun CHUNG ; Hye Sung WON ; So Ra KIM ; Mi Deok SEO ; Cheon Hwang BO ; Hong Kwon KIM ; Pil Ryang LEE ; In Sik LEE ; Ahm KIM
Korean Journal of Obstetrics and Gynecology 2000;43(10):1894-1899
No abstract available.
Catheters*
;
Cystic Adenomatoid Malformation of Lung, Congenital*
;
Fetal Therapies*
;
Lung*
10.The Developement of An Objective Test for Visual Acuity Assessment Using Optokinetic Nystagmus Stimuli Presented Head-Mounted Display: Seohan Objective Visual Acuity Test.
Minseop KIM ; Yong Suk CHOI ; Wen Nam LU ; Kun LEE ; Jeong Min HWANG ; Won Ryang WEE ; Jin Hak LEE
Journal of the Korean Ophthalmological Society 2000;41(4):871-878
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*