The prevalence and risk factors for pterygium in South Korea: the Korea National Health and Nutrition Examination Survey (KNHANES) 2009-2010 / 한국역학회지

OBJECTIVES: To determine the prevalence and risk factors for pterygium in the adult Korean population of South Korea. METHODS: Data were analyzed from 9,193 participants who were 40 years of age or older from the Korea National Health and Nutrition Examination Survey (KNHANES), conducted from 2009 to 2010. Standardized slit-lamp examinations were performed by study ophthalmologists to examine the anterior segment for evidence of pterygium. Pterygium was graded clinically as T1 (atrophic), T2 (intermediate), or T3 (opaque). Every participant underwent ocular and systemic examinations, as well as interviewer-administered questionnaires. Any evidence of pterygium and observed association between the risk factors were recorded. RESULTS: The mean age of the subjects was 55.7 (±0.2) years. Of the 9,193 eligible subjects, 935 had pterygium in at least one eye. In a multivariate logistic regression analysis adjusted for age and sex, pterygium was significantly associated with rural vs. urban residence (odds ratio [OR], 1.7; 95% confidence interval [CI], 1.4 to 2.0), lower level of education (OR, 4.5; 95% CI, 3.1 to 6.6), low income (OR, 1.3; 95% CI, 1.0 to 1.8), smoking (OR, 0.7; 95% CI, 0.5 to 1.0), and more hours of sun exposure (OR, 1.5; 95% CI, 1.2 to 1.8). After adjusting for all variables, the prevalence of pterygium was significantly associated with age, sex, residence, education level, and smoking. CONCLUSIONS: This is a nationwide epidemiologic study in South Korea to assess the prevalence of and risk factors for pterygium. The overall prevalence of pterygium was 8.8% among Koreans aged 40 years or older. Older age, male gender, rural residence, lower level of education, and non-smoking were associated with the development of pterygium.

Prevalence of Eye Diseases in South Korea: Data from the Korea National Health and Nutrition Examination Survey 2008-2009

PURPOSE: The aim of this study is to report on preliminary data regarding the prevalence of major eye diseases in Korea. METHODS: We obtained data from the Korea National Health and Nutrition Examination Survey, a nation-wide cross-sectional survey and examinations of the non-institutionalized civilian population in South Korea (n = 14,606), conducted from July 2008 to December 2009. Field survey teams included an ophthalmologist, nurses, and interviewers, traveled with a mobile examination unit and performed interviews and ophthalmologic examinations. RESULTS: The prevalence of visual impairment, myopia, hyperopia and astigmatism in participants over 5 years of age was 0.4 +/- 0.1%, 53.7 +/- 0.6%, 10.7 +/- 0.4%, and 58.0 +/- 0.6%, respectively. The prevalence of strabismus and blepharoptosis in participants over 3 years of age was 1.5 +/- 0.1% and 11.0 +/- 0.8%, respectively. In participants over 40 years of age, the prevalence of cataract, pterygium, early and late age-related macular degeneration, diabetic retinopathy and glaucoma was 40.2 +/- 1.3%, 8.9 +/- 0.5%, 5.1 +/- 0.3%, 0.5 +/- 0.1%, 13.4 +/- 1.5%, and 2.1 +/- 0.2%, respectively. CONCLUSIONS: This is the first nation-wide epidemiologic study conducted in South Korea for assessment of the prevalence of eye diseases by both the Korean Ophthalmologic Society and the Korea Center for Disease Control and Prevention. This study will provide preliminary information for use in further investigation, prevention, and management of eye diseases in Korea.

Comparison of Visual Function Between Two Aspheric Intraocular Lenses After Microcoaxial Cataract Surgery

PURPOSE: To compare the visual function and postoperative refraction between two aspheric intraocular lenses (IOLs) after microcoaxial cataract surgery. METHODS: A prospective analysis of 60 eyes of 58 patients who had undergone microcoaxial phacoemulsification and implantation of aspheric IOLs (AcrySof IQ, 30 eyes; Akreos MI60, 30 eyes) was performed. The best corrected visual acuity (BCVA), spherical equivalent, intraocular pressure (IOP), corneal thickness, endothelial cell density (ECD), predictability of postoperative spherical equivalent, higher order aberrations, contrast sensitivity test, satisfaction, and glare were evaluated during the follow-up period of three months. RESULTS: There were no significant differences in BCVA, spherical equivalent, IOP, corneal thickness, or ECD (p>0.05). The predictability of the postoperative spherical equivalent in the AcrySof IQ and Akreos MI60 IOL groups was not significantly different (p=0.59), and the two groups showed good anterior-posterior stability during the postoperative three months. There were no significant differences in higher order aberrations, contrast sensitivity test, satisfaction or glare (p>0.05). CONCLUSIONS: Both AcrySof IQ and Akreos MI60 implantation groups showed similar visual functions and postoperative spherical equivalents after microcoaxial cataract surgery.

Comparison of Clinical Results Between Two Spherical Aberraion-Free Intraocular Lenses

PURPOSE: To compare the postoperative outcomes between Akreos MI60 and Akreos AO intraocular lens (IOLs) after cataract surgery. METHODS: A prospective analysis among 55 eyes of 55 patients who had undergone microcoaxial phacoemulsification and implantation of aspheric IOLs (Akreos MI60, 30 eyes; Akreos Adapt-AO, 25 eyes) was performed. The best corrected visual acuity (BCVA), spherical equivalent, intraocular pressure (IOP), corneal thickness, endothelial cell density (ECD), surgically induced astigmatism (SIA), predictability of postoperative spherical equivalent, higher order aberrations, and contrast sensitivity test were evaluated during the follow-up period of 3 months. RESULTS: There were no significant differences in BCVA, spherical equivalent, IOP, corneal thickness, ECD, SIA, higher order aberrations and contrast sensitivity test (p>0.05). The predictability of postoperative spherical equivalent in the Akreos Adapt-AO (-0.57+/-0.22D) represented statistically significant myopic shift compared with the Akreos MI60 group (-0.05+/-0.69D) (p=0.02). CONCLUSIONS: Both the Akreos MI60 and the Akreos Adapt-AO implantation groups performed similiarly, following cataract surgery, showed similar visual function.

Three Cases of Secondary Fungal Infection in Herpes Simplex Keratitis

PURPOSE: To report several cases of secondary infection by fungus in herpes simplex keratitis. CASE SUMMARY: A retrospective chart review was performed on 3 eyes of 3 patients who were without improvement and diagnosed with fungal keratitis by smear and culture on prior presentation with herpetic keratitis. Two cases were diagnosed with fungal keratitis, based on the results of culture. Fungal keratitis by Candida albicans was improved with antifungal agents, but a case caused by Fusarium species was more aggravated, regardless of antifungal agents. One case was improved by antifungal medications, which was diagnosed with fungal keratitis by the fungal hyphae manifestation on KOH preparation. CONCLUSIONS: Secondary microbial infection should be considered, when the lesion had no improvement with antiviral agents in herpetic keratitis.

The Changes of Corneal Astigmatism and Refraction After Horizontal Rectus Muscle Surgery in Intermittent Exotropia

PURPOSE: To investigate changes in corneal astigmatism and refractive power in intermittent exotropia after lateral rectus recession with or without medial rectus resection. METHODS: We compared visual acuity, spherical equivalent, refractive power, astigmatism from cycloplegic refraction, and Orbscan corneal topography in two groups consisting of 40 eyes from 20 patients who underwent bilateral lateral rectus recession (Group 1) and 33 eyes from 33 patients who underwent monocular medial rectus resection with lateral rectus recession (Group 2) immediately preoperatively and at 1 and 4 weeks postoperatively. RESULTS: In Group 1, the refractive power changed +0.12 D on average in the horizontal median and -0.08 D on average in the vertical median at 1 week postoperatively. The refractive power changed +0.07 D on average in the horizontal median and -0.04 D on average in the vertical median at 4 weeks postoperatively. No significant change in the corneal astigmatic axis was detected. In Group 2, the refractive power changed +0.4 D on average in the horizontal median and -0.19D on average in the vertical median, and the corneal astigmatic axis significantly shifted by +0.51 D in the 'with-the-rule astigmatism' direction at 1 week postoperatively (p=0.02). However, the refractive power changed +0.2 D on average in the horizontal median and -0.09 D on average in the vertical median, and the corneal astigmatic axis changed +0.2 D at 4 weeks postoperatively, although these values were not statistically significant. CONCLUSIONS: Postoperative refractive power and corneal astigmatism did not change significantly, as compared to preoperative values, at 4 weeks postoperatively in the lateral rectus recession-only or medial-and-lateral rectus recession group.

The Effect of Dorzolamide-Timolol and Latanoprost on Redox Cycle in Aqueous Humor of Rabbit

PURPOSE: To evaluate the effect of dorzolamide-timolol and latanoprost on redox cycle of superoxide dismutase (SOD) and ascorbic acid in the aqueous humor of the rabbit. METHODS: Group 1 (20 eyes of 10 rabbits) was instilled with dorzolamide-timolol in the right eye and Group 2 (20 eyes of 10 rabbits) was instilled with latanoprost in the same manner. Four weeks after instillation, SOD activity and ascorbic acid concentration were analyzed. RESULTS: In Group 1, SOD activity and ascorbic acid concentration of the right eye and left eye were 15.7% and 19.3% (p=0.27), 2.7 pM and 2.6 pM (p=0.47), respectively. In Group 2, SOD activity and ascorbic acid concentration of the right and left eye were 22.3% and 27.6% (p=0.14), 2.3 pM and 2.1 pM (p=0.89), respectively. CONCLUSIONS: There was no significant difference of SOD activity and ascorbic acid concentration between both eyes in Group 1 and 2.