No abstract available.
Lenses, Intraocular*

Introduction: Microbial keratitis is one of the most challenging complications of contact lens (CL) wear. Proper CL practice plays an important role to reduce the risk for contact lens related microbial keratitis (CLRMK). Methods: This multi-centre case-control study was conducted from January 2008 until June 2009 to determine the risk factors associated with CLRMK. Cases were defined as respondents who were treated for CLRMK, whilst controls were respondents who were contact lens wearers without microbial keratitis. Ninety four cases were compared to 94 controls to determine the risk factors for CLRMK. Results: The predictors for CLRMK were: Not washing hands with soap before handling CL (aOR 2.979, CI 1.020, 8.701 p=0.046), not performing rubbing technique whilst cleaning the CL (aOR 3.006, CI 1.198, 7.538 p=0.019) and, not cleaning the lens case with multipurpose solution daily (aOR 3.242 CI 1.463, 7.186 p=0.004). Sleeping overnight with the CL in the eye (aOR 2.864, CI 0.978, 8.386 p=0.049) and overall non-compliance with lens care procedures (aOR 2.590, CI 1.003, 6.689 p=0.049) contributed significantly to CLRMK. Conclusion: Health education and promotion in contact lens care are important and should be conducted by eye care practitioners to reduce the occurrence of CLRMK.
Contact Lenses

Objective: To compare the antimicrobial effects of locally available multipurpose contact lens solutions (MPS) on the growth of standard strains of contact lens-related ocular pathogens and to establish the recommended duration of exposure to these solutions to achieve maximal antimicrobial efficacy. Methods: This study, a single-blind controlled experiment, evaluated five locally available MPS in terms of their antimicrobial efficacy towards common contact lens-related ocular pathogens, such as P. aeroginosa, S. aureus, E. coli, F. solani, and C. albicans, using the stand alone criteria. Microbial viability counts were obtained at serial durations: after 1 hour, 3 hours, 6 hours, and 12 hours of exposure. Results: MPS containing polyquaternium-1 and myristamidopropyl dimethylamine (MAPD) and polyhexamide reduced the bacterial concentrations by 3 log and fungal concentrations by 1 log, enabling them to fulfill the stand alone criteria for disinfecting solutions as mandated by ISO/CD 14729. This antimicrobial efficacy was most evident at 6 hours of exposure to the challenge organisms. MPS containing polyquaternium-1 and MAPD also have the broadest spectrum of effectivity against gram-negative and gram-positive bacteria, and C. albicans. All MPS tested have poor microbial activity against F. solani. Conclusion Multipurpose contact lens solutions demonstrated variability in their antimicrobial activity. MPS with broad spectrum efficacy and effectivity, such as those containing polyquaternum and MAPD, are preferred to prevent contact lens-related ocular infections.
Contact Lenses

UV-absorption method was able to determine protease activities in various kinds of enzymatic cleaners. Bioclen G and O2 had high protease activeities at room temperature and were effective for artificial protein deposits; Bioclen G is safe for the eyes because enzyme was inactivated at 70 degrees C. Both products were better enzymatic cleaners for both hard and soft contact lenses. Hydrocare-F was effective for removing artificial protein deposits. For the sake of safety against the eyes, there was a problem in that this product had too high protease activity at 90 degrees C. Protease activities were generally lower or showed great variations at 10~30 degrees C for other products. These had lower cleaning effect for artificial protein deposits on rigid gas permeable contact lenses.
Contact Lenses* ; Contact Lenses, Hydrophilic

UV-absorption method was able to determine protease activities in various kinds of enzymatic cleaners. Bioclen G and O2 had high protease activities at room temperature and were effective for artificial protein deposits; Bioclen G is safe for the eyes because enzyme was inactivated at 70 degrees C. Both products were better enzymatic cleaners for both hard and soft contact lenses. Hydrocare-F was effctive for removing artificial protein deposits. For the sake of safety against the eyes, there was a problem in that this product had too high proteasea activity at 90 degrees C. Protease activities were generally lower or showed great variations at 10 ~ 30 degrees C for other products. These had lower cleaning effect for artificial protein deposits on rigid gas permeable contact lenses.
Contact Lenses* ; Contact Lenses, Hydrophilic

PURPOSE: To evaluate the vault change after implantable collamer lens (ICL) size exchange according to the preoperative vault. METHODS: In 14 eyes of 13 patients, the vault change after ICL exchange operation due to unideal vault was compared in 2 groups, the smaller ICL exchanged group and larger ICL exchanged group. RESULTS: In 6 out of 14 eyes, the ICL was exchanged to a 0.5 mm smaller size and the vault was changed from 1.38 mm (1.18-1.70) to 0.71 mm (0.51-0.92) (p = 0.03). In 8 eyes, the ICL was exchanged to a 0.5 mm bigger size and the vault was changed from 0.07 mm (0.03-0.13) to 0.50 mm (0.12-1.01) (p < 0.01). The exchange operation was performed at 3.5 postoperative days (1-6) if the ICL was exchanged to 1 step smaller size, but the exchange operation was performed at 135 postoperative days (90-660) if the ICL was exchanged to 1 step bigger size (p < 0.01). CONCLUSIONS: ICL exchange to 1 step smaller or bigger size is an effective method to correct unideal postoperative vault to a more ideal vault size. The exchange to 1 step smaller size ICL tended to be performed sooner.
Humans ; Phakic Intraocular Lenses*

No abstract available.
Dislocations* ; Phakic Intraocular Lenses*

Intraocular lens power was calculated from data of axial length, corneal curvature, and anterior chamber depth in 112 eyes which underwent IOL implant surgery. Postoperative refractions of 112 eyes were analyzed into three groups such as the group of which constant A is 116.2, the group of which constant A is 116.8, and TI-59 system group. The results were as follows; 1. The A constant derived from retrograde analysis in our 112 cases was 116.2. In the cases of the constant A 116.2, error of predicted required spectacle lens power was -0.16D +/- 0.89 in relative average, 0.67D +/- 0.57 in absolute average. Using the standard formula described by Hoffer, the accuracy of IOL power calculation by the constant 116.2 was 76.1% +/- 1.0D / 97.4% +/- 2.0D / +2.42 to -2.11D. 2. The specific constant A of intraocular lenses inserted in our hospital was 116.8. In the cases of the constant A 116.8, error of predicted required spectacle lens power was -0.39D +/- 0.88 in relative average, 0.75D +/- 0.60 in absolute average. Using the standard formula described by Hoffer, the accuracy of IOL power calculated by the constant A 116.8 was 72% +/- 1.0D / 96% +/- 2.0D / +2.34 to -2,50D. 3. In TI-59 system of IOL power calculation, error of predicted required spectacle lens power was -0.12D +/- 1.0D in relative average and 0.75D +/- 0.66 in absolute average. Using the staudard formula described by Hoffer, the accuracy of IOL power calculation in this method was 73% +/- 1.0D / 91.5% +/- 2.0D / +2.77 to -2.31D. 4. There was a significant difference between the error of the A constant 116.2 and that of 116.8(P. 0.05), but wasn't between the error of the A constant 116.2 and that of TI-59 system. 5. In the case of axial length 21mm +/- 0.5, the IOL power calculation by the A constant 116.2 was the most accurate among three groups.
Anterior Chamber ; Lenses, Intraocular*

PURPOSE: To evaluate the accuracy of the SRK II formula for the AMO Array(R) multifocal intraocular lens (Array lens) power calculation according to axial length. In case of refractive error more than +/- 1.0 diopter (D), we compared the accuracy of the SRK II with that of other formulas. METHODS: Participants were 178 eyes (142 patients) received the Array lens. These were divided into 3 subgroups based on axial length. Group I had 21 eyes of short axial length (less than 22.0 mm). Group II had 133 eyes of average axial length (more than 22.0mm below 24.5mm). Group III had 24 eyes of long axial length (more than 24.5mm). The difference between preoperative predicted refractive value and postoperative manifest refractive value were calculated. We compared the accuracy of the SRK II and that of SRK/T, Holladay formulas in case of refractive error more than +/- 1.0D. RESULTS: Three eyes (14.2%) in Group I, 14 eyes (10.5%) in group II and 15 eyes (62.5%) in Group III showed refractive errors more than +/- 1.0D. Fifteen eyes (62.5%) in Group III were significantly reduced to 7 eyes (29.1%) with using SRK/T, Holladay formulas. CONCLUSIONS: SRK II formula had better predictive accuracy in axial length less than 24.5mm with Array lens. But it is better to apply SRK/T or Holladay formulas when axial length is more than 24.5mm.
Lenses, Intraocular* ; Refractive Errors*

The times of uptake and release of pilocarpine solution by soft contact lenses were studied with spectrophometer in vitro. The uptake time was about 30 minutes and the releasing time was stationary after 30 minutes. The lower concentriction of pilocarpine solution was generally rapid uptake and release than higher.
Contact Lenses, Hydrophilic* ; Pilocarpine*