• Journal of Korean Ophthalmic Optics Society
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• v.15 no.4
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• pp.339-346
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• 2010

Purpose: The study was performed to compare the difference of non-invasive tear break-up time (NIBUT) with alignment or steep fitting of soft contact lens in normal and dry eyes. Methods: Total 40 eyes (aged 20~30 years) were classified to the normal (n=20) or dry eye group (n=20) by the diagnosis methods for dry eyes and worn soft contact lens (polymacon material) with alignment or steep fitting. NIBUTs of lens wearers were separately measured at the points of before wearing, immediately after wearing and after stabilization of tear film. Results: With alignment fitting, averaged NIBUT in the dry eye group after stabilization of tear film was not significantly different from that of the normal eye group. However, averaged NIBUTs in the normal and dry eyes had significant difference when measured immediately after lens wearing. However, the number of eyes having NIBUT less than 4.0 second was 30% higher compared to the number of normal eyes with steep fitting when measured immediately after wearing. Some shorten NIBUT in dry eyes with steep fitting was also shown after stabilization of tear film. Conclusions: These results suggest that wearing soft contact lens in dry eyes differently affect tear film compared to normal eyes. Thus, dry eyes need more advertent fitting for contact lens wearing because of unstable tear film.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.1
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• pp.15-20
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• 2008

Purpose: To study on the confidence of dry eye diagnosis methods which need to prescribe contact lens. Methods: Non-invasive tear film break-up time (NIBUT) and tear film break-up time (TBUT) were measured in forty healthy subjects in their 20s, and then the subjects were classified into normal eye and dry eye. The results of McMonnies questionnaire, tear prism height measurement, Hardtack test, blink rate measurement and Schirmer test were compared with the results of NIBUT and TBUT. Results: The results of NIBUT and TBUT were as follows; 20 subjects had normal eyes, 10 subjects had dry eyes in both NIBUT and TBUT, and 10 subjects showed different results. In McMonnies questionnaire, the score of normal eye group averaged 8.2 and that of dry eye group averaged 18.5, which showed statistically significant difference. Furthermore, 100% of normal eye group classified by the results of NIBUT and TBUT corresponded with the result of McMonnies questionnaire and 90% of dry eye group showed the correspondence. Tear prism height of normal eye group averaged 0.32 mm and that of dry eye group averaged 0.23 mm, which were significantly different. Hardtack test, blink rate measurement and Schirmer test without local anesthesia showed no statistically significant difference between normal eye group and dry eye group. Conclusions: On dry eye diagnosis methods, the results of McMonnies questionnaire and tear prism height measurement had close correlation with the results of NIBUT and TBUT.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.91-98
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• 2000

To investigate the distribution of dry eye and to accept diagnosis methods of dry eye in ophthalmic shop, this study was performed on 81 persons(male : 49, female : 32). 1. We divided two group for diagnosing dry eye by dry eye screening questionnaire : one was dry eye symptom group(49.3%) and the other was non-dry eye symptom group(50.7%). 2. Non-invasive break-up time(NIBUT) which was measured by using Tear $scope^{(R)}$ (Killer. co)was longer than invasive break-up time(IBUT). 3. A blink rate in dry eye symptom group(10%) was measured lesser than 10 cycle/min, in non-dry eye symptom group(14.9%). 4. In shirmer test there were lesser than 10mm/5min in dry eye symptom group(67.5%), in non-dry eye symptom group(39%). 5. Cornea and conjunctival staining by rose bengal represented Mild 25%, medium 36.25%, extreme 38.75% in dry eye symptom group. Non-dry eye symptom group was showed Mild 19.51%, medium 14.63%, extreme 12.19%. 6. These results showed that the patient showed dry eye symptom in 3 items of eye examination was 22.5%, 4 items 25%, 5 items 30%, 6 items 15%.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.4
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• pp.429-439
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• 2013

Purpose: This study was assessed to investigate the change of subjective and/or objective symptoms and the light transmissibility of lens caused by over-usage of daily disposable circle contact lenses (circle lens). Methods: Three daily disposable circle lenses made of etafilcon A, hilafilcon B, and nelfilcon A were applied on 20 normal eyes free from any eye diseases by when subjects complained any kind of discomfort. On the first and the last days of lens wearing, subjective discomfort, blinking rate, non-invasive break-up time, lens centration on corneal surface and visible light transmissibility of lens were recorded at every case and compared. Results: The circle lens wearers complained discomfort when they wore the circle lens more than 15 hours, in excess of 8 hours being the recommended wearing time and the most circle lens wearers quit the lens wearing when they wore more than 30 hours. On the last day of lens wearing, the representative subjective discomforts were stiffness, dryness and tiredness. When the subjects wore circle lens more than the recommended time, a tendency of increased blinking rate and decreased NIBUT was observed when it compared with the values right after lens wearing. On the last day of lens wearing, the lens centration was shown to be decentrated from the pupil center compared with the centration right after the wearing. These changes in lens centration and blinking rate were consistently shown in all cases of lens wearing however, the difference in the degree of subjective and/or objective change was present depending on lens materials and subjects. The visible light transmissibility of circle lens has largely been changed. Conclusions: From these results, it was thought that the decreased NIBUT induced dryness and stiffness and decreased visible light transmissibility caused more blinking when daily disposable circle lens was exceedingly used, which provoked lens decentration and subjective discomfort. However, the difference of subjective and/or objective change was largely varied in accordance with the lens material types and individuality and thus it may occur some unexpected problems by the individual base. Therefore, the education about the necessity to comply with the recommended wearing time and the problem will be essential.

• 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.

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.3
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• pp.191-201
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• 2016

Purpose: In the present study, the effect of artificial tears with different ingredients on tear film stability and subjective symptoms of dry eyes in the early stage of soft contact lenses wear was investigated. Methods: The three kinds of artificial tears and saline solution were respectively applied onto 50 dry eyes which wore soft contact lenses made of etafilcon A. Then, non-invasive tear film break-up time (NIBUT) was measured at every five minutes for 30 minutes right after the instillation of artificial tears, and the changes in blink rate and subjective symptoms were estimated after 30 minutes from the instillations. Results: All three kinds of artificial tears increased NIBUT larger than saline. The effect of increasing NIBUT immediately after the instillation of artificial tears was the largest when the artificial tear containing viscosity enhancer was used. The duration time of the effect was the longest when the artificial tear having both surfactant and viscosity enhancer was applied. The blink rate was not significantly changed when both artificial tears and saline solution were instilled. Subjective symptoms were significantly improved by the instillation of both artificial tears and saline solution and dryness, irritation, tiredness, stiffness, dazzling were improved by the use of most solutions. However, the subjective symptoms were rebounded to the level before the instillation of artificial tears after 30 minute-instillation. Conclusions: It was revealed that both artificial tears and saline solution could improve the subjective symptoms of dry eye in the early stage of soft contac lenses however, the effect of these solutions on the tear film stability was different according to the components. From the results, it is suggested that the proper selection of artificial tears is necessary for the improvement of dry eye symptoms at the early stage of soft contact lenses wear in dry eye.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.2
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• pp.147-157
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• 2011

Purpose: The present study was conducted to investigate the actual condition of circle lens wear and the differences caused by the pigmentation in blinking rate, non-invasive tear break-up time (NIBUT), and lens surface between circle and soft contact lens wear during clinical application. Methods: Eighty subjects were surveyed to know the actual condition of wearing circle lens. Blink rate, NIBUT of 20 subjects in twenties were measured after separately wearing soft contact lens and circle lens for 5 days. Their lens surfaces were also observed by scanning electron microscope. Results: Fifty percent of circle lens wearers answered that major reason for changing circle lens was discomfort and 67% of answerers wore circle lens more than 6 hours a day. The tendency of increased blink rates in both wearers of circle and soft contact lens at 30 minutes later when tear film stabilized and 3 hour after lens wearing was shown on the 1st, 3rd and 5th day with expanding wearing time. Especially at 3 hours after lens wearing on the 3rd and 5th day, the difference of blink rates was statistically different in circle lens wear and soft contact lens wear. The NIBUTs of soft contact lens wearers and circle lens wearers were 6.0 and 3.7 secs, respectively, at 30 min later on 1st day and were significantly different. NIBUTs of soft contact lens wearers and circle lens wearers were also statistically different 3 hrs after lens wearing on the 1st day and the similar pattern of NIBUTs was shown on the 3rd and 5th day. The roughness of both surfaces in soft contact lens and front surface in circle lens was same. However, pigmented front surface of circle lens was rougher and uneven. Conclusions: As the results, the circle lens wearers might feel discomfort in clinical application since the difference in lens surface of circle lens would change lens wettability during wearing. The difference by tinting contact lens was shown from the result, which could help better wearing circle lens.