• Journal of Korean Ophthalmic Optics Society
• /
• v.5 no.2
• /
• pp.107-113
• /
• 2000

This study has analyzed soft contact lens care-after-sale and periodic examinations at optical shops and eye clinics. And I wish to make that use of educational data for the soft contact lens lesson of the department of ocular optics. This questionnaire studied the status of care for soft contact lens and periodic examination, of students who wears soft contact lens. The results are as follows: First, 7.5% of students questioned wore soft contact lens. More women than men wore soft contact lens. The soft contact lens wearers purchased lens mainly at optical shops. 78.5% of them wore daily wear lens. Because of cosmetic advantages of soft contact lens. 47.9% of them wore soft contact lens. 72.5% of them wore soft contact lens less than 12 hours per a day. 32.0% of them has worn soft contact lens more than 6 months less than 1 year. 51.1% of them experienced irritation. 39.7% of them have exchanged soft contact lens between 6 and 9 months. Secondly, when purchasing lenses. 60% of soft contact lens wearers were given instructions of general care, such as duration of wearing lens, how to remove protein, how to store, and how to sterilize at both of eye clinics and optical shops. But the proportion of instructions, such as side effects and periodic examination which were given to soft contact lens wearers, is lower both at eye clinics and optical shops. Especially at optical shops, the proportion of instruction for periodic examination, is lower than at eye clinics(p<0.05). Thirdly, The proportion of operations of periodic examinations after use of soft contact lens both at eye clinics and optical shops, is low. The soft contact lens wearers have had more periodic examinations at eye clinics than at optical shops. But the rate of non-periodic examination at optical shop is 87.9%. And for periodic examinations, general care was done at optical shops. On the other hand, eye examinations, general care, and treatments were done more at eye clinics. Fourthly, 60.3% of the soft contact lens wearers understood the necessity of the periodic examinations, but actually, only 6.4% of them were given the schedule for the periodic examinations, and 2.5% of them were given at an optical shop(p<0.01).

• Journal of Korean Ophthalmic Optics Society
• /
• v.7 no.1
• /
• pp.69-73
• /
• 2002

This questionnaire studied the status of wear and care for soft contact lens, of 200students wearing loft contact lens. 50% of man wore soft contact lens, 8 hours and 52% of woman wore soft contact lens 10 hours per a day, 51% of man has worn soft contact lens 3 years 45% of woman has worn soft contact lens 3 year. For the side effects of wearing contact lens 39% of man soft contact lens wearers experienced eye congestion, 72% of woman soft contact lens wearers dryness eyes.

• Proceedings of the KAIS Fall Conference
• /
• 2010.11b
• /
• pp.677-680
• /
• 2010

본 연구는 경기도 구리시의 2개 초등학교 5, 6학년 학생을 대상으로 시력 저하 실태 및 그와 관련된 요인들을 알아보고 시력 저하 예방교육의 기초자료로 활용하고자 시도 된 연구이다. 자료의 수집은 2009년 11월 1일부터 12월 10일까지 초등학교 5학년, 6학년 학생 793명(남 417명, 여 376명)이었고 2009학년도의 시력검사자료 분석과 문헌 및 기존의 조사도구를 토대로 개발한 자가 보고식 설문지를 이용하여 조사하였다. 자료 분석은 SPSS WIN 12.0(한글판)프로그램을 이용하여 빈도, 백분율, $x^2$-test 및 로지스틱 회귀분석의 통계적 방법으로 분석하였다. 시력저하에 유의한 영향요인으로 좌측시력을 종속변수로 한 경우 중 일반특성에 따른 변수인 부모 및 형제와 자매가 안경 및 렌즈 착용하는 경우, 경제적으로 어려울수록 시력 저하 자가 많았고, 환경특성에 따른 변수인 거실 및 방안밝기가 어두울수록, 컴퓨터 사용 시 실내밝기가 어두울수록, TV의 눈높이 및 컴퓨터 모니터의 눈높이가 높을수록 시력 저하 자가 많았다. 우측시력을 종속변수로 한 경우 중 일반특성에 따른 변수인 부모가 안경 및 렌즈를 착용할수록, 형제 와 자매가 안경 및 렌즈를 착용할수록, 경제적으로 어려울수록 시력 저하 자가 많았고, 환경특성에 따른 변수인 거실 및 방안밝기가 어두울수록, 컴퓨터 사용 시 실내밝기가 어두울수록, TV의 눈높이 및 컴퓨터 모니터의 눈높이가 높을수록 시력 저하 자가 많았다. 안경 및 렌즈를 종속변수로 한 경우 중 일반특성에 따른 변수인 부모 및 형제와 자매가 안경 및 렌즈를 착용할수록, 경제적으로 어려울수록 시력 저하 자가 많았으며, 환경특성에 따른 변수인 거실 및 방안밝기의 실내밝기가 어두울수록, TV의 눈높이 및 컴퓨터 모니터의 눈높이가 높을수록 시력 저하 자가 많았다. 눈 건강상태를 종속변수로 한 경우 중 일반특성에 따른 변수인 경제적으로 어려울수록 시력 저하 자가 많았고, 건강행동특성에 따른 변수인 주관적인 건강상태가 나쁠수록, 눈 피로감이 있을수록 시력 저하 자가 많았으며 환경특성에 따른 변수인 거실 및 방안밝기의 실내 밝기가 어두울수록 시력 저하 자가 많았다. 시력저하관련 요인을 연구한 결과 학생들의 시력 저하 자가 매년 증가하고 있다는 것을 알 수 있었고, 유전적 요인에 의한 시력저하는 개인의 노력에 의하여 사전예방이 어렵지만 환경적 요인에 의한 시력저하는 노력과 관심으로 사전예방이 가능하므로 학생들의 시력건강증진을 위하여 학부모와 학교 및 전문 의료기관이 서로 연계적인 협조 하에 학생들 개개인에 맞는 효율적인 시력증진관리프로그램 개발하는 것이 필요하고, 현행학교시력검사의 정확성을 기하기 위하여 표준화된 시력검사 지침을 개발하여 사용할 필요가 있으며, 지역 및 환경적 배경이 다르다 보니 연구결과가 다르게 나타나는 경우가 있는데 객관적인 결과를 도출하기 위하여 여러 지역의 학생을 대상으로 다양하고 체계적인 연구를 해야 할 필요성이 있다고 생각한다.

• Journal of the Korea Convergence Society
• /
• v.10 no.12
• /
• pp.447-451
• /
• 2019

This study were to investigate the scratches and replacement cycles of eyeglasses according to personal characteristics in daily life. The subjects were 58 people who voluntarily participated in this study. The replacement cycle of eyeglasses according to the contact of eyelashes with eyeglasses, type and the number of eyeglasses wiped on a day were analyzed. The statistical analysis were performed by X² test and Fisher's exact test. The average replacement cycle of the eyeglasses were longer females than males. The eyeglasses replacement cycle were significantly shorter when the eyelashes contacted the eyeglasses and when the eyeglasses were wiped using a tissue or clothes other than the eyeglasses towel. The coating film of the eyeglasses may be damaged by the convergence effect such as eyelashes or minor carelessness in daily life, and this study will continue to follow up on this result.

• Journal of Korean Ophthalmic Optics Society
• /
• v.20 no.2
• /
• pp.117-124
• /
• 2015

Purpose: The purpose of this study was to compare the accommodative function of young adult in their 20s wearing monovision, modified monovision, and aspheric multifocal contact lenses at near task. Methods: Thirty young adults ($23.53{\pm}2.37years$) were fitted with monovision, modified monovision (the application of single vision contact lenses and center-near low addition aspheric multifocal contact lenses), and aspheric center-near multifocal contact lenses. After wearing these modalities during a week for adaption, and after watching visual display at computer for inducing accommodative pressure for 1 hour. The following assessments of accommodative function were made: contrast visual acuity (VA) at distance and near; accommodative response; near accommodative facility; and negative relative accommodation (NRA)/positive relative accommodation (PRA). All measurements were carried out binocularly. Results: In binocular distance VA with contrast of 10%, monovision was the worst among the four modalities (p=0.005). In accommodative response at 1 m (1.00 D), monovision was the lowest (p<0.05) and accommodative response at 40 cm (2.50 D) with monovision was lower than that of modified monovision and multifocal contact lens (p<0.05). We also found that there were no significant differences in accommodative facility and NRA/PRA among the four modalities. Conclusions: In young adult (20s), monovision with low add reduced the accommodative response at near task, however, modified monovision and multifocal lens with center-near type did not affect accommodative relaxation.

• Journal of Korean Ophthalmic Optics Society
• /
• v.20 no.2
• /
• pp.237-246
• /
• 2015

Purpose: The present study was conducted to reveal the correlation of structural denaturation and decrease of enzyme activity when the antioxidative enzymes, superoxide dismutase (SOD) and catalase (CAT) were repeatedly exposed to UV-B, and further investigate whether the denaturation and inactivation of those enzymes can be effectively blocked by using UV-inhibitory RGP lens. Methods: Each enzyme solution was prepared from the standardized SOD and CAT, and repeatedly exposed to UV-B of 312 nm for 30 minutes, 1 hour and 2 hours a day over 1, 2, 3, 4 and 5 days. Structural denaturation of SOD and CAT induced by repeat UV-B irradiation was confirmed by the electrophoretic analysis, and their enzyme activity was determined by the colorimetric assay using the proper assay kit. At that time, the change in structure and activity of the antioxidant enzymes directly exposed to UV-B was compared to the case that UV-B was blocked by UV-inhibitory RGP lens. Results: SOD exposed repeatedly to UV-B showed the polymerization pattern in the electrophoretic analysis when it repeatedly exposed for 30 min a day, however, the change of its activity was less than 10%. On the other hand, CAT repeatedly exposed to UV-B reduced size and density of the electrophoretic band which indicated a structure denaturation, and its activity was significantly decreased. In the case that the repeat exposure time was longer, CAT activity was completely lost even though some enzyme band occurred in the electrphoretic analysis. In addition, the degeneration of CAT due to UV-B irradiation was inhibited to some extent by using RGP lens with a UV-B blocking of 63.7%, however, it was not completely inhibited. Conclusions: From these results, it was revealed that the structural denaturation of antioxidative enzymes was not perfectly correlated with the reduction in enzyme activity according to the type of enzyme. It is recommended to minimize the exposure time to UV when wearing contact lens, or wear the contact lenses having UV blocking rate of the FDA Class I blocker or the sunglasses having equivalent UV-blocking rate for reducing the damage of antioxidative enzymes induced by UV.

• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.3
• /
• pp.295-303
• /
• 2014

Purpose: This study aims to observe bleaching resulted from multipurpose contact lens solutions used to manage lenses with the subjects of colored contact lenses being distributed in Korea. Methods: The lenses have been worn for six months, and their refraction is 0.00D. Three types of colored contact lenses of which margin has been colored with a different manufacturing method have been adopted (type 1: pigment application method, type 2: chemical bonding process, type 3: sandwich method), and multipurpose solutions used were two types containing different components. Each of the colored contact lenses was stored in the multipurpose solutions for 20 days and went through vortexing for 15 seconds per day. Their fluorescence absorbance, surface roughness, brightness index, and color coordinate index were measured before and after the vortexing to see the degree of bleaching. Results: In the two types of multipurpose solutions, every type of the color contact lenses showed no statistically significant difference in their fluorescence absorbance value before and after the vortexing. Regarding surface image, the front surface of the lenses was smooth in every type, and about the back surface, type 3 indicated less protrusion than type 1 and 2. About the difference of color on the lens surface before and after the vortexing, type 3 showed significantly less difference than type 1 and 2; however, all fell into the permissible error. Conclusions: About the bleaching of colored contact lenses resulted from multipurpose solutions for soft contact lenses, there was no difference observed in terms of fluorescence absorbance and color. According to the methods of manufacturing dyes, however, there was difference in the protrusion of the posterior surface image.

• Journal of Korean Ophthalmic Optics Society
• /
• v.16 no.1
• /
• pp.107-116
• /
• 2011

Purpose: The review article was written to establish an excel program that could calculate minimal Dk of contact lens without $O^2$ deficiency and actual $O^2$ concentration on cornea when contact lens were being fitted by changing lens-related factors. Methods: An excel program was formulated to calculate the thickness of post-lens lacrimal layer, Dk of contact lens and $O^2$ concentration on cornea. Results: With the excel program established, minimal $O^2$ concentration needed on cornea could be calculated when the thickness of post-lens lacrimal layer was changed by varying lens-related factors. A different route in the excel program was needed to choose based on the shape of lacrimal layer. The thickness of lacrimal layer was determined by the shape of meniscus made of tear between lens edge and cornea with flat fit. Thus, the $O^2$ concentration showing negative number in calculation decreased on peripheral cornea with flatter fitting and actual $O^2$ concentration would be zero on cornea. With tight fitting, the thickness of post-lens lacrimal layer is much thicker than lens itself thus negative number in calculation by the excel program is shown indicating zero oxygen on cornea. It can cause $O^2$ deficiency regardless of Dk of contact lens. Conclusions: The calculation of thickness of post-lens lacrimal layer and $O^2$ concentration on cornea by the established excel program is suggested to avoid $O^2$ deficiency when fitting state is varied by changing lens-related factors.

• Journal of the Korean Chemical Society
• /
• v.64 no.2
• /
• pp.67-73
• /
• 2020

The study aimed to investigate in vitro lipid deposition of oleic acid, oleic acid methyl ester and cholesterol on a daily disposable (1-day lenses) and 3-days lenses over 3 days and changes of optical characteristics is also investigated. Artificial tear solutions were prepared to simulate actual tear compositions. Two types of contact lenses (1-day lenses (Senofilcon A) and 3-days lenses (silicone tripolymer)) were soaked in the artificial tear solutions within an incubator at 37 ℃ with 150 rpm for 8, 16, 24 hours. Lipid deposition (oleic acid, oleic acid methyl ester and cholesterol) were measured using high performance liquid chromatography (HPLC) instrument. In addition, measurements of oxygen transmissibility, light transmittance and observation of lens surface were conducted. The amount of lipid deposition on the 1-day lenses were 127.55 ㎍/lens for Day 1, 302.96 ㎍/lens, for Day 2, and 353.30 ㎍/lens for Day 3. The 3-days lenses were 46.22 ㎍/lens for Day 1, 66.07 ㎍/lens for Day 2, and 67.45 ㎍/lens for Day 3. Oxygen transmissibility were 81×10^-9(cm/sec)(ml O₂/ml×mmHg)(Baseline) and 48×10^-9(cm/sec)(ml O₂/ml×mmHg) (Day 3) for the 1-day lenses, it were 13.23×10^-9(cm/sec)(ml O₂/ml×mmHg)(Baseline) and 9.6×10^-9(cm/sec)(ml O₂/ml×mmHg) (Day 3) for the 3-days lenses. Transmittance of each lenses were 97.21% (Baseline) and 94.25% (Day 3) for the 1-day lenses, 97.65% (Baseline) and 95.15% (Day 3) for the 3-days lenses. Observation of surface deposition indicated greatest deposition for the 3-days lenses type on Day 3. Lipid deposition for both lens types increased by day and was greater for the 1-day lenses type. Surface deposition appeared to differ as it was greatest for the 3 days lens type, which may suggest other deposits such as protein may be present.

• Journal of Korean Ophthalmic Optics Society
• /
• v.10 no.1
• /
• pp.35-40
• /
• 2005

Subjective and objective visions were measured on young adults(mean 21 yrs, 126 eyes) who were free of any ocular diseases and laser surgery and none wore contact lenses. The aim of this study was to investigate the diurnal variation of vision through subjective and objective measurements. Subjective visual acuity were measured at 5 m three times a day, morning(8:00 AM-10:00 AM), noon(12:00 PM-2:00 PM) and afternoon(4:00 PM-6:00 PM). The instrument used for objective refraction right after visual acuity measurement was Nvision-K 5001(shin-nippon) which unique in being able to disregard subject's accommodation because of its unrestricted viewing conditions. Also, we measured that three times and then calculated the average values. The result showed that an average subjective visual acuity in the morning, noon, afternoon were 0.256(${\pm}0.263$), 0.266(${\pm}0.276$), 0.242(${\pm}0.249$) respectively. Average spherical equivalent power in objective refraction of right eyes showed -3.416 D(${\pm}2.907$), -3.359 D(${\pm}2.735$), -3.297 D(${\pm}2.709$) respectively and dioptric power was decreased from morning to afternoon. Vision changed throughout the day in both subjective and objective measurements nevertheless its variations were statistically insignificant(p<0.05). Therefore it does not seem to matter of time for either visual acuity test or refraction.