• Journal of Korean Ophthalmic Optics Society
• /
• v.12 no.1
• /
• pp.1-7
• /
• 2007

To investigate the momentary movement pattern of soft contact lens(SCL) depending on wearing time, eight types of soft contact lenses were worn by 10 normal subjects and the momentary movements of SCLs were estimated using by high speed camera(FASTCAM ultima 1024). When the momentary movements of SCLs in the cornea between blinkings were compared after 15 min wearing, the vertical movements of all eight SCLs were about 2 times larger than the horizontal movement but the extent of these movement difference was a function of kinds of SCLs. The momentary moving distance of SCL varied from the kinds of SCLs, which A and B lens, daily wear lens, moved significantly larger distance compared with other SCLs. The momentary movements between blinkings decreased significantly after 8hr wear of SCLs. The extents were different when SCLs were compared with each other, which the reduction range of horizontal and vertical movement was 24.6~60.0% and 20.4~94.3%, respectively. The A, B and C lenses which had relatively higher water content showed the larger movement reduction after SCL wear. This results suggest that wearing SCL for some hours decreases the movement of SCl, which can induce the change of tear flow.

• 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.13 no.1
• /
• pp.21-26
• /
• 2008

Purpose: To investigate the proper care system of sample-wearing cosmetic contact lens (SWCCL). Methods: Research on the actual condition about SWCCL was examined in fifty cosmetic contact lens wearer in their 10s and 20s by the questionnaire. Also, the extents of the contamination of gram-negative bacteria and fungi were measured in SWCCL after wearing for 2, 4 and 6 weeks, and it was investigated whether the proper care system could prevented the contamination. Results: As the result of the questionnaire, people purchased the cosmetic contact lens after trying SWCCL with a mean of 4.5. The contamination of gram-negative bacteria and fungi were significantly increased in SWCCL-wearing period-dependent manner. In both Group 1 (rubbing SWCCL and exchanging preserving solution every wearing of SWCCL) and Group 2 (only exchanging preserving solution every wearing of SWCCL without rubbing SWCCL), the contamination of gram-negative bacteria and fungi were prevented perfectly. In the case of Groups having every-week care, the proliferation of gram-negative bacteria and fungi were somewhat suppressed, and rubbing was helpful of decreasing the contamination. The biweekly care had scarcely any effect for preventing the contamination. Conclusions: By exchanging the preserving solution every wearing of SWCCL, the contamination of gram-negative bacteria and fungi could be suppressed perfectly.

• Journal of Korean Ophthalmic Optics Society
• /
• v.21 no.3
• /
• pp.215-225
• /
• 2016

Purpose: The aim of this study was to figure out how the characteristics of soft contact lens materials and pigmentation affect the adherence of C. albicans on soft contact lenses pre-deposited with tear constituents. Methods: The adherent number of C. albicans on clear soft contact lenses (hereinafter clear lenses) and circle soft contact lenses (hereinafter circle lenses) made of etafilcon A, hilaiflcon B and nelfilcon A, respectively, was measured before and after the deposition of artificial tear. Also, bacteria adherence on lenses were observed by a scanning electron microscope. Results: Adherence of C. albicans was significantly different according to lens materials. The amount of adsorption was not different between clear lenses and circle lenses made of etafilcon A however, the number of bacteria absorption was bigger in hilafilcon B and nelfilcon A lenses. More absorption of C. albicans was found in the non-pigmented central area compared the pigmented area, and non-pigmented peripheral area has more bacterial absorption than non-pigmented central area. The number of C. albicans decreased in the case that tear protein was pre-deposited. The maintenance of antibacterial activity against C. albicans was different according to lens materials thus, etafilcon A has the longest period of its maintenance. Conclusions: It was revealed that the number of C. albicans was different according to the characteristics of lens materials, pigmentation or non-pigmentation, the pigmented area of soft contact lenses. Thus, it is suggested that the management method should be different according to the adsorption characteristics of C. albicans.

• Journal of Korean Ophthalmic Optics Society
• /
• v.18 no.3
• /
• pp.271-277
• /
• 2013

Purpose: The purpose was to study the corneal refractive power changes associated with the wearing of everted silicone hydrogel soft lenses. Methods: The corneal refractive power and corneal astigmatism were measured using corneal topographer (CT-1000, Shin-nippon Co., Japan) for checking change of corneal refractive power and objective refractive error was measured by auto-refractometer (Natural vision-K 5001, Shin-nippon Co., Japan). We measured at baseline and 1 week after lens wearing. Results: The correcting of corneal refractive power could be effective in low myopia. It's more effective to the higher power of greatest meridian of cornea and the more corneal astigmatism. 73% of subjects' refractive error was decrease less than 1 D and 17% of the subjects had an reverse effect (increase) occurs. The reduction of objective refractive error was more effective when cornea refractive power was great or corneal astigmatism was much. Conclusions: Pressure which the everted silicone hydrogel lens to the cornea could be caused. It occurred as the degrees of corneal power, corneal astigmatism and objective refractive error differences. Selection of an appropriate subject is important considering difficulty of changing the parameters of the lens.

• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.4
• /
• pp.487-492
• /
• 2014

Purpose: This study relates to the development of the 3X scope, whose objective part is configured with a doublet + a meniscus lens. Methods: By the initial condition of the objective part having a configuration of a doublet + a singlet, we could optimize the optical system of scope in order to minimize the finite ray aberrations of the objective part and the whole optical system of scope, and so we could develope a new type 3X scope. Results: On the condition of the objective part having a configuration of a doublet + a singlet, when the optical system of scope was optimized in order to minimize the finite ray aberrations, we could find that the singlet became the meniscus type lens having the concave shape to the direction of the doublet, and the longer the distance between the doublet and the meniscus lens is, the more the finite ray aberrations are minimized. Conclusions: In this study, we could develope a new type 3X scope of which finite ray aberrations can be reduced to 1/14 than the existing scope by adopting the objective part of the 3X scope having a configuration of three lenses composed of a doublet + a singlet. We could confirm that this reduction of aberrations can be a means to increase the effective aperture than the existing scope and to shorten the length of the optical system.

• Journal of Korean Ophthalmic Optics Society
• /
• v.7 no.2
• /
• pp.13-18
• /
• 2002

This study conducts the soft contact lenses user's understanding and contentment of training while at the place of purchase. It is based on a questionnaire to the residents in and outside the Masan area, aged between ten to thirty, who have worn soft contact lenses. It examines the training of using contact lenses and lens-care products, the period of wearing lenses, exchanging lenses, sterilizing lenses, side effects of using lenses or the periodic examination, and the understanding and contentment of the users during the training. The results of the research are as below : First, the understanding of training of using lenses, using lens-care products, the period of wearing lenses, exchanging lenses was high, but it was low for the training of sterilizing lenses, side effects of wearing lenses or the periodic examination. Second, the contentment of training of using lenses, lens-care products, the period of wearing lenses, exchanging lenses was high, but low for the training of sterilizing lenses, side effects of wearing lenses or the periodic examination. Therefore, the trainer of the contact lenses must easily and sincerely explain sterilizing lenses, the side effects of using lenses and the periodic examination, cheek with the users, and provide guidelines so as to improve the understanding and the contentment of training of using contact lenses.

• Journal of Korean Ophthalmic Optics Society
• /
• v.21 no.2
• /
• pp.109-117
• /
• 2016

Purpose: The study was aimed to figure out the effect of materials and pigmentation of soft contact lens on the adherence of Staphylococcus aureus upon soft contact lenses deposited with tear components. Methods: The number of adherent S. aureus on clear and circle soft contact lenses made of etafilcon A, hilafilcon B, nelfilcon A was measured before and after incubation in artificial tear. Furthermore, the denaturalization level of tear protein with time after incubation in artificial tear was estimated by electrophoresis. Results: The adherence of S. aureus was significantly different according to the lens materials. The pattern of bacterial adherence on clear and circle contact lenses was different. That is, the adherent amount of S. aureus was somewhat larger on circle lens made of etafilcon A however, amount on circle lenses made of hilafilcon B and nelfilcon A was 89.3% and 71.3% of the number on clear lenses. When the tear protein was deposited on contact lenses, the number of adherent bacteria decreased and its degree was varied according to the lens material. The degree of decrease was the biggest in clear soft lens made of etafilcon A. Anti-bacterial effect of tear protein decreased with time after deposition of tear protein on soft contact lens and the amount of lysozyme also decreased. The reduction of anti-bacterial effect and quantity of lysozyme was different according to contact lens materials and pigmentation. Conclusions: It was revealed that the adherence of S. aureus depends on contact lens materials and pigmentation, and the specification of lens material affects more on adherence of S.aureus than pigmentation. It was further figured out the denaturalization level of anti-bacterial protein on soft contact lens varies according to lens materials and pigmentation, which produces an effect on the quantity of bacterial adherence.

• Applied Microscopy
• /
• v.36 no.3
• /
• pp.227-234
• /
• 2006

To investigate the comparative effect of spherical and aspherical RGP lens were worn during 3 weeks on rabbit's cornea. Four white rabbits were worn right eyes with spherical lens and 4 white rabbits were worn right eyes with aspherical RGP lens. Left eyes were served as control. The rabbits were sacrificed at 3 weeks after fitting and observed morphological changes by scanning electron microscopy and also investigate proliferation rate of the corneal epithelium with RGP wearing. After spherical RGP lens wearing, the epithet layer damaged compared to aspherical lens. The superficial cell layer strip off seriously, cell size significantly changed abnormal. Both spherical and aspherical RGP lens fitting group showed so many bacteria and back surface of lens was found like a fern shape. The aspherical RGP lens original material type was some formal than spherical lens. We thought that these pattern was significantly altered with spherical lens by prohibited transmitter oxygen from atmosphere therefore the epithelium shape was changed. This suggested wearing the aspherical lens might be less physiologic than shperical lens fitting.

• Journal of Integrative Natural Science
• /
• v.13 no.1
• /
• pp.13-18
• /
• 2020

This study used cerium iron hydroxide nanoparticle with HEMA (2-hydroxyethyl methacrylate), the cross-linker EGDMA (ethylene glycol dimethacrylate), NVP (N-vinyl-2-pyrrolidone) and the initiator AIBN (azobisisobutyronitrile) for copolymerization. Also, the physical properties of the prepared lenses were compared, and their applicability as polymers for ophthalmic materials was experimented. The results of the measurement showed that the UV blocking rate and the wettability increased with the cerium iron hydroxide nanoparticles addition ratio, and the refractive index and water content were not affected. Thus, the produced copolymer is expected to be useful as a functional contact lens material while satisfying the basic physical properties of the hydrogel contact lens.