• Journal of Korean Ophthalmic Optics Society
• /
• v.4 no.2
• /
• pp.87-90
• /
• 1999

After we compared the Unaided visual acuity and the Corrected visual acuity who were wearing eyeglasses, over second grade of elementary school in Chonju and Iksan, we could get conclusions like these. 1. The grades are getting higher, there are more who are wearing eyeglasses. 2. Unaided visual acuity becomes worse but and Corrected visual acuity becomes better according to older. 3. There are 23 eye, (17.8%) in boys and 38 eye, (19.2%) in girls who have below 0.6 of the Corrected visual acuity who have to change their eyeglasses. 4. If Unaided visual acuity is getting better, Corrected visual acuity is betre. 5. There were 4 boys (6.2%) and 9 girls (9%) is Anisometropia.

• Proceedings of the Optical Society of Korea Conference
• /
• 2003.07a
• /
• pp.72-73
• /
• 2003

시력 진단장비로는 자각식 측정법인 시력표, 타각식 계측기로는 검영기와 자동굴절력측정기 등이 있으나 눈도 일반 광학계와 같이 공간적으로 불균일한 광학적 특성을 가지기 때문에 눈의 광학적 기능을 정확하게 진단하기 위해서는 광학수차의 공간 분포를 정밀하게 측정할 필요가 있다. 광학수차는 시력의 한계를 규정하고 안광학 기기의 설계에 있어서 중요한 요소이다. 눈의 광학수차를 측정하기 위한 파면분석기에는 공간분해굴절계, Tscherning 파면분석기, 광선추적파면분석기, 주사실틈굴절계, 그리고 Shack-Hartmann 파면분석기(SH 파면분석기) 등이 있으며, SH 파면분석기는 적응광학계에서도 유용하게 사용되고 있다. (중략)

• Journal of The Korean Ophthalmological Society
• /
• v.59 no.11
• /
• pp.1030-1038
• /
• 2018

Purpose: To evaluate whether early visual acuity response at 4 weeks after the first intravitreal anti-vascular endothelial growth factor (VEGF) injection or 4 weeks after the third injection in neovascular age-related macular degeneration (nAMD) is associated with 12-month follow-up outcome. Methods: Thirty treatment-naive patients (30 eyes) with nAMD, treated with intravitreal anti-VEGF, were retrospectively included. Initially, all patients were injected at least three times for three consecutive months and followed up with a pro re nata regimen for at least 12 months. The relationship between 4 weeks after the first and third anti-VEGF injections in visual acuity response was explored, including the mean change from baseline in best-corrected visual acuity (BCVA). The mean change in BCVA was classified into three groups according to visual improvement: <1, 1-<3, or ${\geq}3$ logMAR line(s) in BCVA. The associations among baseline characteristics (gender, age, duration of symptoms, initial BCVA, central macular thickness, and intraocular pressure) and visual acuity responses 4 weeks after the first and third anti-VEGF injections were also assessed. Results: The proportions of eyes with <1, 1-<3, and ${\geq}3-line(s)$ improvement at 4 weeks after the first injection were 6 eyes (20%), 7 eyes (23.3%), and 17 eyes (56.6%), respectively. The proportions of eyes with <1, 1-<3, and ${\geq}3-line(s)$ improvement at 4 weeks after the third injection were 9 eyes (30%), 9 eyes (30%), and 12 eyes (40%), respectively. A BCVA response ${\geq}3-lines$ improvement at 4 weeks after the third injection showed significant associations with ${\geq}3-line(s)$ improvement and BCVA response at 12 months in multiple logistic and linear regression analyses (p = 0.04). Conclusions: In this study, BCVA response ${\geq}3-lines$ improvement at 4 weeks after the third injection showed a significant association with ${\geq}3-line(s)$ improvement and BCVA response at 12 months.

• Journal of Korean Ophthalmic Optics Society
• /
• v.21 no.1
• /
• pp.23-34
• /
• 2016

Purpose: In the present study, the effect of circle contact lenses wear on contrast sensitivity and glare sensitivity in a refractive surgery group was investigated. Methods: The contrast sensitivity and glare sensitivity were evaluated using by CGT-1000 for a non-refractive surgery group as control group(40 eyes) and a refractive surgery group(30 eyes) applied plano circle contact lenses, and pupil size was also measured. The correlation between contrast/glare sensitivity and the pupil size was analyzed. Results: In the refractive surgery group, contrast sensitivity in the range of high spatial frequency decreased with wearing circle contact lenses, and amount of decrease for the refractive surgery group was larger than for the control group. The correlation between pupil size and the change of contrast sensitivity was decreased by wearing circle contact lenses, and the correlation was lower in the refractive surgery group than the control group. Furthermore, the wear of circle contact lenses affected on glare sensitivity. In analyzing the change of glare sensitivity by pupil size, the glare was larger in the refractive surgery group than control group. Circle contact lenses in refractive surgery group were not fitted on the center of cornea. Conclusions: In the present study, it is suggested that the sufficient understanding and consideration about the decrease of contrast sensitivity and the increase of glare by wearing circle contact lenses after the refractive surgery is necessary.

• Journal of Korean Ophthalmic Optics Society
• /
• v.2 no.1
• /
• pp.77-83
• /
• 1997

This study was carried out to investigate the effect of environmental factors on 380 children's unaided visual acuity and to determine the visual acuity and objective refraction error of these children. The unaided visual acuity and objective refraction error were measured by the TOPCON chart projector and refractometer on 147 kindergarteners and 233 primary school children ranging from age 5 to 12. The measurement on the unaided visual acuity of children were 3% for below the 0.1 visual acuity 9% for 0.1~0.4. 18% for 0.5~0.7. 16% for 0.8~0.9. and 54% for over 1.0 visual acuity respectively. The refractive errors were 9.35% for mixed astigmatism. 14.5% for hyperopia 75.88% for myopia. and 0.27% for emmetropia. respectively. When analyzing the environmental factors. the relationship between the children's visual acuity and the number of hours the children watched TV. the more hours they watched TV. the more the children lost their visual acuity. The visual acuity of children decreased abruptly in the groups that watched TV more than 4 hour a day. When comparing the relationship between the children's visual acuity and proximity to the TV, the further away from the TV they were the higher visual acuity. There is rna relation between the children's visual acuity and the studying hour or reading hour of children. The relationship between the children's visual acuity and their dwelling environment, the visual acuity of children who lived in an independent house were better than the visual acuity of children who dwelled in an apartment.

• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.3
• /
• pp.371-376
• /
• 2014

Purpose: The aim of this study was to explore the effect of artificially decreased eye in normal vision on eye-hand coordination (EHC) when using the Lee-Ryan Eye-Hand Coordination Test recently reported. Methods: Eleven adults with normal vision aged $29.46{\pm}5.94$ years participated for this study where a non-dominant eye artificially induced moderate refractive amblyopic vision at near by adding a plus lens conducted EHC tasks and then did the test again under normal vision following 2 weeks. To investigate the ability of EHC, 7 tasks including individually different level of difficulty in the Lee-Ryan EHC Test were selected to compare and analyze EHC in terms of two independent variables such as time taken and the number of errors. Results: In time taken, subjects with artificially decreased vision took more time than normal vision under monocular conditions (p=0.013), while those with the decreased vision completed their tasks faster than normal vision under binocular conditions (p=0.001). In the number of errors, subjects with the decreased vision made more mistakes (p<0.001) as shown in time taken, whereas there was no difference between monocular and binocular viewing conditions in the decreased vision. Conclusions: Unlike previous EHC tests including limitations for application, deficit in EHC can be screened by the Lee-Ryan EHC Test developed based on simple computer-based system. Therefore, it is considered that further studies relevant to deficits in visual function such as amblyopia will be carried out in clinics as well as research.

• Journal of Korean Ophthalmic Optics Society
• /
• v.21 no.3
• /
• pp.253-257
• /
• 2016

Purpose: To determine whether the distance between objects and the size of object are factors to be able to affect dynamic stereoacuity. Methods: Subjects were 37 adults (26 males and 11 females) with an average age of $23.89{\pm}1.76$. Refractive error was fully corrected for all subjects and each visual acuity of them was over 0.9. Three rods test was performed for measurement of stereoacuity. The viewing angles from left rod to right rod were set $5^{\circ}$, $10^{\circ}$, and $15^{\circ}$ and the rod thickness used 7 mm, 14 mm, and 21 mm, respectively. Stereoacuity was repeatedly measured three times in each test condition at 2.5 m distance, and reported the average value of them. Results: When rod thickness was 7 mm or 14 mm, dynamic stereoacuity decreased as the viewing angle increased, and they were significantly decreased (p<0.01) at viewing angles of $10^{\circ}$ and $15^{\circ}$ as compared with that of at $5^{\circ}$, respectively. When rod thickness was 21 mm, dynamic stereoacuity decreased as the viewing angle increased, especially, that of at $15^{\circ}$ decreased significantly (p<0.01) as compared with that of at $5^{\circ}$. The dynamic stereoacuity depending on the rod thickness have an increasing tendency as the rod thickness increased. Conclusions: The viewing angle between objects and the size of viewing object were factors that affect to dynamic stereoacuity.

• Journal of Korean Ophthalmic Optics Society
• /
• v.14 no.2
• /
• pp.53-59
• /
• 2009

Purpose: The aims of this study are to conduct a fact-finding survey of eyeglasses use based on the visual acuity of middle and high school students in Busan. Methods: A total of 821 middle and high school students from four different schools participated by Self-administered qustionnaire test on July, 2007. Results: Among these students, 74.3% of the students had low vision and 66.26% of the students wore eyeglasses. The percentage of non glasses-wearers were 13.77% in low vision and 15.26% of the students had low vision in glasses-wearers. The reason why they did not wear eye glasses and why they did not change eyeglasses prescription was they did not feel any inconvenience in their usual life. Conclusions: Many students have bad eyesight due to limited spheres of environment and they do not feel any inconvenience of non-wearing eyeglasses in spire of their bad eyesight.

• Journal of Digital Convergence
• /
• v.13 no.12
• /
• pp.285-290
• /
• 2015

The purpose of this study is to compare the status of eyesight according to the change of astigmatism axis in myopic astigmatism and to minimize errors in making astigmatic glasses based on accurate optometry and prescription. The subjects were 93 males and females(186 eyes) who have myopic astigmatism without any ocular disease or systemic disease. We performed comparative analysis on the status of visual acuity according to the change of astigmatism axis to 5, 10 and 15 degree in corrected eyesight 1.0. The direct astigmatism was the most common astigmatism type among the 186 eyes. After all subjects were perfectly corrected into 1.0, the change of astigmatism axis affected eyesight; The results suggested that the more change was made in astigmatism axis, the worse their eyesight would become. The main astigmatism type was changed from direct astigmatism to inverse astigmatism as age increased. The change of the astigmatism axis resulted in failing of corrected eyesight. Therefore, the convergence of examination and correction for astigmatism strength and axis is necessary when conducting refraction inspection for astigmatism.

• Journal of Korean Ophthalmic Optics Society
• /
• v.9 no.2
• /
• pp.345-352
• /
• 2004

We investigated the effect of age at initial correction, of 44 refractive amblyopic patients duration of correction on corrected visual acuity with the lapse of time for mean 33months(3months-59months). Full cycloplegic corrections were prescribed at the initial visit to all subjects. The distribution of initial corrected visual acuity was 0.02 to 0.5. Age at initial correction varied from 3 years to 12 years. The refractive error appeared to have the greatest influence on the visual outcome, showing continuous visual improvement after initial correction. But the age at initial correction did not appear to influence on the initial and final corrected visual acuity showed a significant difference, irrespective of age at the initial correction Or degree of anisometropia.