• Journal of Korean Ophthalmic Optics Society
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• v.13 no.3
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• pp.19-28
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• 2008

Purpose: To understand symptoms and signs in soft contact lens wearers the authors evaluate the attribution of the tear test to the contact lens related symptoms and signs. Methods: Sixty-two healthy soft contact lens wearers (23.95${\pm}$4.38 years old, 18.60${\pm}$16.92 months of prior lens wear) were participated in this study. 3 kinds of tear test and McMonnies' questionnaire test were performed for the soft contact lens wearers and subjective symptoms and objective signs were graded using CCLRU scales during the study period. Results: In this surveys, we found ocular dryness, redness and tiredness are the most common frequent and severe symptoms in soft contact lens wearers. Frequency of the ocular dryness, redness and tiredness are associated with grittiness, burning sensation and foreign body sensation respectively, and severity of the photophobia, foreign body sensation are associated with unstable vision and grittiness and which are associated with score of McMonnies' Questionnaire. Conjunctival redness and limbal redness are major signs but those are not need to be clinical care and rarely occurred corneal and conjunctival staining which are associated with tear break-up-time statistically. Conclusions: Dryness, redness and tiredness are primary common symptoms in Korean soft contact lens wearers. The frequency of those symptoms are increased with the period of soft contact lens wear and those are associated with other symptoms but have no relationship with signs.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.2
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• pp.13-18
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• 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
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• v.10 no.2
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• pp.151-157
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• 2005

The purpose of this study is to get related appropriate data for correct awareness and education of the university students who are using contact lens by investigating university students' awareness, present status, using habits and complication of contact lens. The method of survey was made by questionnaires which were spread to the group of 408 university students. The result indicated some characteristics including using daily wear soft lens of 55.7%, the major motive of using them is for cosmetics of 45.6%. Among them, 54.9% experienced complication, and the xerophthalmia was the most conspicuous case in the aspect of the kinds of the complication. In the aspect of the place where they purchased the contact lens, 93% of the users bought them at eye glasses stores. But when they experienced inconveniences of the contact lens, only 18.8% consulted the Stores. In the fact, I think, the users don't seem to trust the stores fully. Furthermore, 43.5% endure the inconveniences when they get them without any treatment. The fact indicates that they don't realize the seriousness of the complication due to contact lens. Reviewing above-stated facts, information and education for correct awareness and managing methods of contact lens, the complication seem 10 be required. In addition, optician specialized knowledge on contact lens and the sense of duty on national eye health improvement seem to be required.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.4
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• pp.445-454
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• 2015

Purpose: The present study was aimed to investigate the effect of tear volume on a change of axial rotation according to wearing time of toric soft contact lens and gaze directions. Method: Toric soft contact lenses with double thin zone design applied on 62 eyes. Then, changes in non invasive tear film break-up time and the rotational direction/amount of lens when changing gaze direction were respectively measured after 15 minutes and 6 hours of lens wear. Results: Lens rotation to temporal direction was more found when changing gaze direction after lens wear. However, its rotation was varied according to wearing time and the subjects' tear volume. Furthermore, the frequency of lens rotation to temporal direction was higher in dry eyes compared with normal eyes at nearly all gaze directions after 15 minutes and 6 hour of lens wear. The rotational amount of lens was generally greater in dry eyes after 15 minutes of lens wear. However, its difference between normal eyes and dry eyes was not great after 6 hours of lens wear. Conclusion: The present study revealed that axial rotation of toric soft contact lens was varied according to the wearer's tear volume and lens rotational patterns at the initial, and extending periods of lens wear were different. The change in rotational pattern of toric soft contact lens from these results means the possibility of visual change after extending lens wear, and the identification of its correlation with tear volume suggests the necessity of considering factors for choosing appropriate toric soft contact lens.

• Journal of Korean Ophthalmic Optics Society
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• v.3 no.1
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• pp.249-258
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• 1998

This study was researched the state and problem of the soft contact Lens wear by the history and inverted microscopy. The results was as follows; 1. The first use of contact lens wear was the 15 years and the last use was the 26 years. The first age of most contact lens wear was the 19 years. 2. In the almost contact lens wearers, the first visual test was the optical shop. 3. At present, almost soft contact lens purchase the optical shop 4. At present, most contact lens wearer like a soft type. 5. At present, most soft contact lens were a domestic production, and some subjects were foreign country production, but some subjects were unknown. 6. After contact lens wear, most subjects don't known the corrected visual acuity, especially, almost people don't known the binocular visual acuity. 7. At present, on soft contact lens color, the teens like the non-color contact lens, twenties like the color contact lens, but thirties was not known. 8. On the advantage of soft contact lens knowledge, most teens and twenties were only one, thirties was unknown. 9. On the disadvantage of soft contact lens knowledge, most teens and thirties were only one, twenties were two. 10. On the side effect of soft contact lens wearer, teens was one, and twenties and thirties don't known. 11. On the main symptoms of soft contact lens wearer, total kinds were seven, On these kinds, most subjects were not symptoms, the next order was unknown on the symptom. But, On the symptoms, the main symptoms was the pain and dry eye. 12. At present, the research on the surface morphology of soft contact lens by inverted microscope, the lens repture, lens folding, foreign body immersion and etc were present. Above the study, most contact lens was soft lens, and the purchase was the optical shop, on the other hand, the knowledge of soft contact lens and visual acuity was few. As a results, On the practical problems of soft contact lens wear, the optician have to the soft contact lens treatment and aftercare by law and educational supporting.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.1
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• pp.19-25
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• 2013

Purpose: The degree of the pupil covered with tinted region of circle soft contact lens was determined according to the illuminant conditions in everyday life and the change of visual acuity by its covering was further investigated. Methods: The circle contact lens having the non-tinted area of 6.2 mm in the center of the lens was applied on 82 eyes in their 20s and their minimum separable visual acuity and minimum legible visual acuity were determined under the luminances of 50 and 370 lux. Results: The covering of pupil was not found when wearing circle contact lens under 370 lux, however, some pupil covering ranged from 0.40 to 1.70 mm was observed in all subjects under 50 lux. The minimum separable visual acuity and minimum legible visual acuity were significantly decreased by the wearing of circle contact lens under 50 lux and the correlation between the larger pupil size of subjects and more decrease of visual acuity was observed. Furthermore, the decrease of minimum separable visual acuity was larger than the case of minimum legible visual acuity indicating that minimum separable visual acuity was largely affected by the covering of pupil. Conclusions: The consideration is necessary for the lens wearers and the manufacturers since the wearing circle contact lens in low-light indoor or nighttime activities may affect directly visual acuity.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.4
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• pp.55-69
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• 2007

The purpose of this study was to perform a clinical test using ez NANOsence II RGP contact lenses for the effects of visual acuity and cornea on subjects with abnormal refraction status. One hundred twenty one adults (twenty nine males, ninety two females, range = 17 to 43, mean = 22.86) were recorded. The subject's history including, the symptoms from previous lens wear, were studied. The subjects were observed, both pre and post lens wear, for any symptoms and signs of change of the eye. The Visual acuity and the binocular status were tested at the far distance using the contact lens. The refraction test was performed on the naked eye using the objective method (Topcon KR-8100, Japan). The Stereopsis test was performed at the near distance after contact lens wear by the Titmus fly (Stereo Optical Co., U.S.A) and TNO (TECH, The netherlands). The contrast sensitivity diagnosis was performed at 1m distance after contact lens wear by the contrast sensitivity chart (pelli-Robertson, USA). The corneal topography was analyzed on the naked eye after lens wear by ORB scan (Bausch Lomb, U.S.A.). The ultra structure of surface on the contact lens was observed using SEM (JMS-5800, Japan). The chemical component's of the contact lens was analyzed by EDS program. The results of this study were as follows: 1. The longer of contact lens wear period, The subjects have acquired the most improved visual function. 2. Subjects had experienced few side effects wearing the contact lenses. 3. The lenses were easy to use by the subjects. 4. The longer of contact lens wear period, the power of cornea had more decrease. but the base curve of cornea had more increase and corneal astigmatism was decrease (p<0.01). Also, the thickness of corneal center was few decrease. 5. Longer periods of using the contact lens showed stereopsis and contrast sensitivity at more normal values. 6 The corneal topographical after lens wear showed most subjects with similar morphology for different wear periods. 7. The surface ultrastructure of the new and used contact lens was the similar fine shape. 8. The chemical component's of in the new and used contact appeared to have similar results. In conclusion, this study showed that the surface ultrastructure and chemical component's of the new and used contact lens are similar. In addition, the subjects had improved the quality of vision and few experienced any side effects during long periods of contact lens wear. Also they have decrease of corneal astigmatism during the long period of lens wear. Our test has showed that the chemical composition and fine structure of contact lens have related to the visual function on contact lens wearer. In this paper, we suggested that ez NANOsence II RGP contact lenses had a moderate effect for correcting vision of abnormal refraction eye.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.1
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• pp.21-26
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• 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
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• v.16 no.3
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• pp.255-264
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• 2011

Purpose: To study the effect of hyaluronic acid(HA), which was widely used in artificial tears, multi-purpose solution(MPS), cosmetics, and drug acting on the musculo-skeletal system, in wettability and comfort of contact lens, we compared HA including lens(+HA) with HA excluding lens(-HA) by clinical evaluation. Methods: During four weeks, the selected 28 university student volunteers who did not have any eye disease wore +HA contact lens on their right eyes, and -HA contact lens on their left eyes, and then compared right eyes to left eyes as control. After prescribing by spherical equivalent calculation, over-refraction by auto-refractometer, and contact lens wearing for two weeks and four weeks, tear evaluation, the anterior of eyes examination, fitting convenience evaluation, surface wetting test, surveys were checked up. Results: Compared with the control group (-HA contact lens), +HA contact lens provided better wetting properties. The amount of released tear in -HA contact lens group became less in four weeks than before, but that in +HA contact lens group showed no significant difference from the initial one. In terms of the redness in eye, there was no significant difference between +HA and -HA contact lens groups. Fitting of +HA contact lens on eye was much easier than the control, -HA contact lens. From the results of survey, comfort, wettability, ease of cleaning, and dryness of eye in +HA contact lens group were generally better than those of -HA group, but redness and contact lens handling showed little difference. Conclusions: The addition of HA in soft contact lens(+HA) may enhance the wettability of lens during lens wearing, resulted in the better comfortable wearing of lens eventually.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.4
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• pp.375-381
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• 2011

Purpose: The purpose of this research was to see how wearing either a SCL or a C-SCL effected the dryness of a person's eye depending on how long they wear either type of lens. Methods: This study was carried out on 52 subjects (104 eyes) who were all in their twenties and had previously experienced wearing contact lenses. All of these subjects were required to wear either a SCL or a C-SCL, which were made out of the same material, for three months. Contents such as the McMonnies Questionnaire survey, the blinking rate per min. and the Noninvasive tear break-up time test (NIBUT) were later conducted on the subjects for this study. Results: According to the results of the McMonnies Questionnaire, it was concluded that the longer the subject wore the SCL and C-SCL, the value of the measurements gradually increased. On the other hand, the results from the NIBUT concluded that the longer the subject wore the SCL, the value of the measurements eventually decreased. However, according to the measurements of the blink rate test, it was concluded that neither results had a significant change. Conclusions: It was concluded that long-term wearing of SCL and C-SCL could be the cause of the induction and progression of dry eyes.