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Significance: Frequent and effective patient-practitioner communication is essential to ensure that instructions regarding contact lens use, care, and maintenance are understood and followed. Given the relevance of good patient compliance, the responsibility of practitioners to provide adequate information may not be neglected., Purpose: This study aimed to determine the content and type of information licensed optometrists in Spain provide their patients during the first contact lens fitting and at follow-up visits., Methods: A self-reported ad hoc survey was distributed to licensed optometrists in Spain to investigate, among other factors, whether practitioners provided information on several aspects of contact lens use and maintenance, how was this information provided, and whether in-office practical demonstrations were conducted at all contact lens appointments., Results: Respondents of 321 surveys had a median of 20 years of contact lens fitting experience and worked on independent practices (67.6%), and national (29.0%) and regional chains (3.4%). Type of practice influenced continuous education habits ( P = .03). Overall, 28.0% of participants did not always instruct patients on the need to rub contact lenses, 34.3% did not always address contact lens replacement, and 6.8% did not always explain storage case hygiene and replacement. At the follow-up visit, only 8.4% of respondents asked their patients to demonstrate their care routines. Information was mostly oral (48.6%) or oral and written (43.0%). Contact lens-related complications were reported more frequently by participants with less continuous education training ( P = .01), by those not always recommending rubbing ( P = .002), and by those not providing written information about storage case hygiene and replacement ( P = .002)., Conclusions: Patient-practitioner communication was good, albeit several areas were identified where information was insufficient or not provided in a correct and timely format. Precise, written information on rubbing and storage case hygiene and replacement may improve compliance and assist in avoiding complications and dropout., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2022 American Academy of Optometry.)

Purpose: To compare the levels of compliance with care routines of orthokeratology (ortho-k) wearers and their parents and to identify factors affecting compliance in a hospital setting in Chengdu, China., Methods: Patients who had worn ortho-k lenses for at least one month were invited to participate in a survey on compliance. Wearers or their parents were required to complete a questionnaire to determine their compliance with hand hygiene, ortho-k lenses and accessory care procedures., Results: A total of 200 wearers, 78 male wearers and 122 female wearers, median age 12 (range 8-18) years were enrolled. Except for use of lens solution, the percentage of participants reporting total compliance with all procedures did not differ significantly between lens wearers and their parents. However, compliance for some items was significantly higher when performed by parents p < 0.001-0.01). 'Eye care practitioner provided instructions' was a significant protective factor for most procedures (p < 0.001-0.04). Age and sex were significant risk factors for some items (p < 0.001-0.04; p = 0.03-0.04, respectively), with girls having higher compliance than boys. 'Parental supervision' was a significant protective factor for some items (p = 0.02-0.04) when wearers performed the procedures themselves. When parents performed lens care procedures, only 'eye care practitioner provided instructions' was a significant variable (p = 0.001-0.04)., Conclusion: Some degree of non-compliance was noted in the majority of ortho-k wearers, particularly for the care of the lens case and suction holder. Compliance with care of some items was higher when performed by parents. Regular reinforcement of care procedures by practitioners is important, especially for older and male lens wearers. Parental supervision is necessary when children perform lens care procedures themselves, even for older wearers., (© 2022 College of Optometrists.)

Significance: Compliance with hygiene and replacement of contact lens (CL) storage cases is key to avoid CL contamination and anterior ocular surface complications. However, compliance levels with these accessories remain low, even in patients with awareness of the risk associated with noncompliance., Purpose: This study aimed to determine level of compliance with common practices regarding CL storage case hygiene and replacement, type of information provided by practitioners, and risk perception., Methods: An ad hoc self-reported survey was used to collect demographic and CL wear details, compliance with storage case care, type of received information, and risk perception (in a 1-to-5 scale). Inferential statistics explored the relationship of demographic details and type of received information with compliance and risk perception., Results: Nondaily disposable wearing participants returned 299 completed surveys, with a median age of 24 years (76.9% females). Monthly replacement silicone hydrogel CLs and multipurpose solutions were predominant. Self-reported compliance with storage case care was poor, with 19.1% of respondents never cleaning their cases, 68.6% exposing them to tap water, and 26.4% failing to replace them within 6 months of acquisition. Two-thirds of respondents received specific information on case maintenance, mainly in oral form. Perceived risk associated with poor-compliance practices was high (median values of 4 and 5), and increased with educational level (P = .02, regarding handwashing; P = .03, regarding case hygiene), with years of CL wear experience (P < .001, regarding handwashing), in those patients provided with specific information on CL case care (P = .01, regarding case replacement)., Conclusions: Compliance with CL storage case hygiene and replacement was generally poor, although awareness of risk associated with noncompliance was high and influenced by factors related to demographic details, CL experience, and patient-practitioner communication. Strategies must be explored to increase risk awareness through education because this may lead to better compliance practices., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2022 American Academy of Optometry.)

Acanthamoeba keratitis infection extends due to the growing number of contact lens users. Indigenous plants including Garcinia mangostana play a vital role in human health and well being. Many species of this plant have been reported with myriads of potent medicinal properties. However, the aims of this study were, for the first time, to isolate compounds from the flower of G. mangostana and to test their anti-Acanthamoeba and anti-adhesion activity against Acanthamoeba triangularis. Powdered flowers of G. mangostana were extracted and chromatographed on a silica gel column. The structures of the compounds were established with the aid of 1 H NMR. More so, the anti-Acanthamoeba and anti-adhesion properties were tested on a 96-well polystyrene microtiter plate and soft contact lenses. Scanning electron microscope (SEM) was used to determine the features of A. triangularis on contact lenses. Eight pure compounds were obtained, namely 9-hydroxycalabaxanthone, tovophillin A, garcinone E, garcinone B, α-mangostin, gartinin, 8-deoxygartinin and γ-mangostin. The extract and pure compounds exhibited anti-Acanthamoeba activity with MIC values in the range of 0.25-1 mg/mL. In addition, the extract and α-mangostin displayed significant activity against the adhesion of A. triangularis trophozoites both in polystyrene plate and in contact lenses at 0.5 × MIC (0.25 mg/mL). Furthermore, α-mangostin has the potential to remove A. triangularis adhesion in contact lenses similar to a commercial multipurpose solution (MPS). SEM study confirmed that crude extract and α-mangostin are effective as solutions for contact lenses, which removed A. triangularis trophozoites within 24 h. Alpha-mangostin was non-toxic to Vero cells at a concentration below 39 μM in 24 h. Crude extract of G. mangostana flower and its α-mangostin serve as candidate compounds in the treatment of Acanthamoeba infection or as lens care solution, since they can be used as a source of natural products against Acanthamoeba and virulence factor associated with the adhesion of A. triangularis., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Purpose: The physical properties of contact lens care solutions and Eye Drops (ED) may affect initial comfort and dry eye symptomatology in contact lens wearers, although these properties are not always provided by manufacturers. The present study aimed to measure and compare the osmolality and pH of commercially available contact lens care solutions and ED., Methods: Forty-four solutions were tested (17 lens care solutions and 27 ED) and classified by the presence and/or combination of the viscosity/lubrication-enhancing ingredients. Solution osmolality was obtained with the Fiske 110 osmometer and pH was measured with a micro-pH 2000. Each measurement was taken ten times, following the manufacturer's instructions, while controlling for room temperature and humidity. Differences between the values of the physical properties of the solutions were analysed by type and viscosity/lubrication-enhancing agent subclassification., Results: Osmolality ranged from 192.6 ± 2.17 to 364.6 ± 2.88 mOsm/Kg, while pH ranged from 6.35 [6.35-6.26] to 7.99 [7.99-8.00]. A significant difference in the osmolality and pH values of contact lens care solutions and ED was found when classified by type or viscosity/lubrication-enhancing agent (ANOVA and Kruskal-Wallis respectively, both p < 0.001)., Conclusions: The physical properties of some contact lens care solutions and ED are not readily available. The osmolality and pH values of various commercially available lens care solutions and ED vary significantly both by type and viscosity/lubrication-enhancing ingredients., (Copyright © 2020 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.)

Objective: The study aimed to assess contact lens (CL) wear and care habits among adults in Sudan., Design: An observational, non-interventional, multi-center, cross-sectional study was conducted in the CL departments of all the eye hospitals and centers, and optical centers in the Khartoum State, Sudan., Participants: Established CL wearers residing in Khartoum State, Sudan., Main Outcomes and Measures: CL wear profile, CL usage habits, hand and CL hygiene habits were assessed using an interviewer-administered questionnaire., Results: The average age of the 442 participants was 24.57 (± 4.87) years. Women comprised 92% of the sample. Smoking was reported by 15.8% of the sample. 81.9% wore soft spherical CL, with 43.4% of the participants were prescribed CL on a yearly replacement schedule. Only 68.3% were prescribed CL by an eye care practitioner. Multipurpose solutions were used by 78.8% of the sample to clean CL, and by 52% to clean the lens case. Compliance rate for CL wear and care among participants was 81.1%. None of the participants reported sharing CL or CL case and rinsing the case with tap water. High compliance level was observed for overnight wear; swimming and showering with CL; handwashing before CL insertion; and cleaning of CL. Moderate compliance rates were recorded for cleaning and replacing lens case, and topping up or sharing solution. Low compliance was noted for attending after care visits., Conclusions and Relevance: CL wearers in Sudan exhibit high to moderate levels of compliance to most contact lens wear and care aspects, except for attending aftercare visits. CL practitioners in Sudan are encouraged to prescribe CL appropriate to the lifestyle and economic situation of patients and actively recommend care products. In addition, practitioners need to follow up with patients to attend aftercare appointments, where hygienic wear and care habits should be emphasized., Competing Interests: The authors have declared that no competing interests exist.

Background: Water exposure during contact lens wear has been associated with contact lens disease including microbial keratitis and sterile corneal infiltrates. Despite the documented risks, water exposure is common amongst lens wearers. This study aimed to determine the effect of water education in the form of "no-water" lens case stickers on water-contact behaviours and storage case contamination., Methods: In a prospective, masked, randomised controlled trial, 200 daily lens wearers were randomised to either receive a storage case with a "no-water" sticker (test) or without a "no-water" sticker (control). Both groups received written compliance information. Participants completed a self-administered lens hygiene questionnaire at baseline and after 6 weeks. Microbial analysis of used storage cases, collected at both study visits, was conducted using ATP and limulus amebocyte lysate (LAL) assays for overall microbial contamination and endotoxin levels, respectively. A one-way ANCOVA and multiple logistic regression determined the change in water-contact behaviours and storage case contamination over time., Results: A total of 188 lens wearers completed both study visits; 128 females and 60 males; average age 29 ± 13 (range 18-78 years); 95 test and 93 control participants. After 6 weeks, the overall water exposure score and endotoxin levels reduced significantly in the test group compared with the control group (p < 0.05). There were no significant changes in individual water-contact behaviours or overall storage case contamination., Conclusion: A no-water infographic on the contact lens case improved overall water-contact behaviours and reduced storage case endotoxin. Refining the messaging may be beneficial in future to improve other aspects of compliance.

Background: Free-living amoebae of the genus Acanthamoeba are cosmopolitan, widely distributed protozoans that cause a severe, vision-threatening corneal infection known as Acanthamoeba keratitis (AK). The majority of the increasing number of AK cases are associated with contact lens use. Appropriate eye hygiene and effective contact lens disinfection are crucial in the prevention of AK because of the lack of effective therapies against it. Currently available multipurpose contact lens disinfection systems are not fully effective against Acanthamoeba trophozoites and cysts. There is an urgent need to increase the disinfecting activity of these systems to prevent AK infections. Synthesized nanoparticles (NPs) have been recently studied and proposed as a new generation of anti-microbial agents. It is also known that some plant metabolites, including tannins, have anti-parasitic activity. The aim of this study was to evaluate the anti-amoebic activity and cytotoxicity of tannic acid-modified silver NPs (AgTANPs) conjugated with selected multipurpose contact lens solutions., Methods: The anti-amoebic activities of pure contact lens care solutions, and NPs conjugated with contact lens care solutions, were examined in vitro by a colorimetric assay based on the oxido-reduction of alamarBlue. The cytotoxicity assays were performed using a fibroblast HS-5 (ATCC CRL-11882) cell line. The results were statistically analysed by ANOVA and Student-Newman-Keuls test using P < 0.05 as the level of statistical significance., Results: We show that the NPs enhance the anti-Acanthamoeba activities of the tested contact lens solutions without increasing their cytotoxicity profiles. The activities are enhanced within the minimal disinfection time recommended by the manufacturers., Conclusions: The conjugation of the selected contact lens solutions with AgTANPs might be a novel and promising approach for the prevention of AK infections among contact lens users.

Medical devices are under strict regulatory oversight worldwide and such regulations prioritise patient safety and efficacy over anything else. Contact lenses fall under the medical device category - a result of direct contact with the eye. Equally regulated are the contact lens care product solutions, which include cleaning and maintenance solutions and lubricating and rewetting drops. In the USA, it is the FDA Centre for Devices and Radiological Health (CDRH) overseeing the regulations of medical devices, since 1976. In the European Union, it is the EU Commission responsible for regulating devices in Member States. The categorisation of contact lenses into medical devices is based on their inherent risk to the wearer. Contact lenses are subject to crucial regulatory oversight from concept to clinical evaluation, clinical investigations through to the finished lens product, and finally, strict conditions associated with their marketing approval including post-marketing surveillance. The physiochemical and manufacturing testing, such as biocompatibility testing alongside pre-clinical stability, sterility and microbiological testing are just some of the essential testing lenses must endure. Only through understanding the inherent risks and potential complications that can arise from contact lens wear, can one truly appreciate the need to adhere to strict regulations. The challenge however, lies in the need for more standardised regulations and flexible approaches, ensuring innovative device technologies reach patients in a timely manner without compromising public health and safety. This review highlights some key requirement, differences and similarities between the FDA and EU administrations in the approval of contact lenses., (Copyright © 2018 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.)

Introduction: Various Acanthamoeba species are free-living organisms widely distributed in the human environment. Amphizoic amoebae as facultative parasites may cause vision-threatening eye disease - Acanthamoeba keratitis, mostly among contact lens wearers. As the number of cases is increasing, and applied therapy often unsuccessful, proper hygienic measures and effective contact lenses disinfection are crucial for the prevention of this disease. Available contact lens solutions are not fully effective against amphizoic amoebae; there is a need to enhance their disinfecting activity to prevent amoebic infections. The use of developing nanotechnology methods already applied with success in the prevention, diagnostic and therapy of other infectious diseases might be helpful regarding amoebic keratitis. This study assesses the in vitro effect of selected contact lens solutions conjugated with nanoparticles against Acanthamoeba trophozoites., Material and Methods: Three selected contact lens solutions conjugated with silver and gold nanoparticles in concentration of 0.25-2.5 ppm were used in vitro against the axenically cultured ATCC 30010 type Acanthamoeba castellanii strain. The anti-amoebic efficacy was examined based on the oxido-reduction of AlamarBlue. The cytotoxicity tests based on the measurement of lactate dehydrogenase (LDH) activity were performed using a fibroblast HS-5 cell line., Results: Enhancement of the anti-amoebic activity of contact lens solutions conjugated with selected nanoparticles expressed in the dose dependent amoebic growth inhibition with a low cytotoxicity profile was observed., Conclusions: Results of the study showed that conjugation of selected contact lens solutions with silver nanoparticles might be a promising approach to prevent Acanthamoeba keratitis among contact lens users.

Purpose: To assess the compliance with contact lens (CL) use among ophthalmologists and other health professionals, and to identify the main noncompliant behaviors., Methods: A cross-sectional, comparative study was designed for soft CL wearers. Twenty-five ophthalmologists, 24 medical doctors other than ophthalmologists, 20 nurses (health professionals), and 52 lay people (members of the public) subjects were included in the interview. The compliance rate for each behavior were determined and compared. Users were asked to rate their subjective use to calculate self-evaluation scores., Results: The compliance rate was found to be the highest among ophthalmologists; however, the difference was not significant (P=0.083). Although the level of compliance was not associated with the subjects' age, duration of lens wear, or wearing days per week (P>0.05), an association was found with the number of wearing hours per day (P=0.010). Increased wearing hours per day was found to increase the rate of poor compliance (P=0.010). Significant differences were found between the groups in storing lenses in fresh solution, lens wearing time according to the ophthalmologist recommendation, and follow-up visits according to ophthalmologist recommendation (P<0.001, P=0.036, P=0.001, respectively). Self-evaluation scores among ophthalmologists, health professionals, and the lay people were 7.56±0.86, 7.59±1.29, and 7.67±1.60, respectively, and no significant differences existed between the groups (P=0.930)., Conclusion: No differences were evident between the groups in terms of good compliance with CL wear and care practices. As this result shows that compliance with CL wear and care practices is not only related to the level of knowledge, different methods should be developed to increase compliance.

Purpose: To ascertain the effect that four contact lens (CL) multipurpose solutions (MPS) have on the viability and release of pro-inflammatory cytokines from human corneal epithelial cells (HCEC)., Methods: HCEC were exposed to four different MPS at various concentrations for 18 hours. The cells were also exposed to phosphate buffer, borate buffer, and PHMB. The cell viability was evaluated using the alamarBlue assay. The release of pro-inflammatory cytokines was measured using a Multiplex electrochemiluminescent assay., Results: MPS-A, MPS-B and MPS-C all reduced cell metabolic activity p < 0.05 from control with MPS-A showing the greatest cytotoxic effect (maximum reduction, 90.6%). In contrast, MPS-D showed no significant reductions in cytotoxicity except at the highest concentration tested (19% reduction at 20% MPS concentration). Of the four cytokines evaluated MPS-C showed a substantial increase in the release of IL-1β, IL-6, IL-8, and TNF-α at higher concentrations when compared to control p < 0.05. At the 20% concentration of MPS-A and MPS-B the release of IL-1 β increased p < 0.05 but the release of IL-6, IL-8, and TNF-α decreased. MPS-D did not cause a change in the release of cytokines IL-1β, IL-6, IL-8 and TNF-α p > 0.05. Exposing the cells to borate buffer and PHMB caused an increase in the release of TNF-α p < 0.05., Conclusions: This investigation demonstrates that at different concentration levels, several of the MPS tested showed a decrease in viability and an increase in the release of inflammatory cytokines from HCEC. The borate buffer component as well as PHMB appears to contribute to this pro-inflammatory reaction., (Copyright © 2017 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.)

Clinical data show that in vitro contact lens friction is related to in vivo comfort. Solutions of biological lubricants hyaluronan (HA) and proteoglycan 4 (PRG4, also known as lubricin) reduce friction at a cornea-polydimethylsiloxane (PDMS) interface. The purpose of this study was to (1) determine if PRG4 can sorb to and lubricate model contact lens materials and (2) assess the boundary lubricating ability of PRG4 and HA compared to saline on model contact lens materials. PRG4 was obtained from bovine cartilage culture and suspended in saline at 300 µg/mL. N,N-Dimethylacrylamidetris (trimethylsiloxy) silane, (DMAA/TRIS) and methacryloxypropyltris (trimethylsiloxy) silane (pHEMA/TRIS) silicone hydrogels were prepared. A previously described in vitro eyelid-hydrogel and cornea-hydrogel biomechanical friction test was used to determine boundary lubricant effect. PRG4 sorption to the hydrogels was assessed using a soak-rinse protocol and western blotting. PRG4 effectively lubricated both silicone hydrogel materials and HA effectively lubricated pHEMA/TRIS, as indicated by a statistically significant reduction in friction compared to the saline control lubricant. An HA and PRG4 combination showed a synergistic effect for pHEMA/TRIS and effectively lubricated DMAA/TRIS. Biological boundary lubricants HA and PRG4 were shown to effectively lubricate silicone hydrogels when in solution. Additionally, HA and PRG4 showed synergistic lubrication for pHEMA/TRIS. The purpose of this study was not to replicate the friction coefficients of contact lenses, but rather to investigate lubricant-surface interactions for common contact lens constituents. These findings contribute to the potential development of biomolecule based lubricant drops for contact lens wearers. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1329-1338, 2018., (© 2017 Wiley Periodicals, Inc.)

Rationale: Contact lens storage cases are known to be contaminated by a significant number of bacteria. However, histamine-producing Raoultella species has not been reported to contaminate contact lens storage case., Patient Concerns: A 27-year-old woman with keratoconjunctivitis that developed in the left eye owing to a cosmetic contact lens and poor hygiene was referred to our hospital. The corrected visual acuity was hand motion., Diagnoses: Corneal infection other than Acanthamoeba keratitis (AK) and corneal hypoxia were excluded., Interventions: We initiated empirical therapy for AK, although no cysts or trophozoites were detected in the cornea and in the lens care solution. Analysis of 16S rDNA sequences from the lens care solution yielded the highest homology with Raoultella species, which are histamine-producing bacteria. Histamine was estimated to be 492 ng/mL in the lens care solution., Outcomes: Her clinical course was distinct from that of usual AK cases. The corrected visual acuity increased up to (1.2) only 5 days after initiating empirical therapy., Lessons: To our knowledge, this is the first report to indicate an association between histamine-producing bacteria and keratoconjunctivitis. We should pay an attention to the microbial contamination of contact lens storage cases by histamine producing bacteria., (Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: To compare subjective comfort and ocular physiology with three multipurpose solutions (MPSs) to that of a peroxide-based system with three different soft contact lens materials., Methods: Habitual soft contact lens wearers (n = 236) were enrolled at three sites and completed a washout period with no contact lens solution for ≥4 days. Subjects were randomly assigned to one of three lens types: etafilcon A, galyfilcon A, or senofilcon A. A new lens of the assigned type was worn for 10 to 14 days each while using one of four care solutions, in random order (A-polyaminopropyl biguanide + polyquaternium, B-POLYQUAD + Aldox, C-alexidine + polyquaternium-1, and D-hydrogen peroxide) with a washout period (≥4 days) between each solution. After each care solution, biomicroscopy was performed and subjective comfort was assessed using the Contact Lens User Experience (CLUE) questionnaire and other instruments including comfortable wear time (CWT). Linear mixed models were used for analysis. Comfort and biomicroscopy signs with each MPS were compared to that of the peroxide solution., Results: Subjective CLUE Comfort score across all lens types with each MPS was not significantly different than with the peroxide solution (p = 0.98). There were no differences in CWT between each MPS and the peroxide solution for any lens type (range of differences: -0.8 to 0.8 h; all p ≥ 0.13). Six MPS/material combinations had no clinically meaningful change in corneal staining versus peroxide (<0.5 units); three combinations could increase staining by up to 0.57 units. Staining was

Background: Conventional procedures for contact lens disinfection, based on solutions with aggressive chemical ingredients, not only affect microorganisms but operate likewise damaging towards the epithelial eye surface., Objective: The aim of this study was to evaluate the applicability of an alternative or complementary disinfection procedure for contact lenses based on irradiation within the visible wavelength range., Methods: Suspensions of S. auricularis, B. subtilis and E. coli were exposed to 405 nm irradiation, for determining the disinfection efficacy. Surviving rates were analyzed by membrane filtration as well as a semi-quantitative analysis using DipSlides., Results: A significant antibacterial effect of the 405 nm irradiation is verifiable for all probed bacteria. Using S. auricularis, there has been no colony forming after an irradiation exposure of 2 hours., Conclusion: The hitherto existing results give reason for the assumption that violet LEDs integrated in contact lens cases will provide a subsidiary disinfection activity and maybe even offer the reduction of chemical ingredients in lens cleaning solutions to become gentler to the eye. In addition the danger of a rerise of the germ concentration after the completion of the disinfection procedure will be reduced.

Objective: To assess the bioburden in an orthokeratology contact lens (OK) care system (defined by microbial identification from OK case fluid) and to identify the risk factors causing high bioburden for pediatric OK wearers in southern Taiwan., Methods: A prospective study for the investigation of bioburden in the OK care system was performed in a tertiary medical center in southern Taiwan. Microbial isolates from the case fluids soaking OKs were analyzed, and pathogenicity was determined. Age, gender, OK experiences, and contact lens care habits were considered the potential risk factors of microbial bioburden (colony-forming units per milliliter) for causal analysis., Results: Forty-one OK wearers (20 female and 21 male subjects) participated in this study. The mean age was 12.7 years, and the mean OK-wearing experience was 3.5 years. A total of 86 microbial strains were isolated from 38 culture-positive specimens. Frequently reported pathogens in contact lens-related microbial keratitis were less common in the current study, but still present, including 4 strains (5%) of Serratia marcescens, 1 strain (1%) of Pseudomonas aeruginosa, and 1 strain (1%) of Staphylococcus aureus. Microbial bioburden of the OK care system was significantly higher (P<0.05) in male subjects., Conclusions: The contamination rate of the OK care system was high, and many isolated microorganisms had potential pathogenicity. Reinforcement of proper contact lens care and education should be mandatory for OK wearers, particularly for male subjects, to decrease the risk of high bioburden of the OK care system.

Hyaluronan (HA) is a hydrophilic biopolymer that has been explored as a wetting agent in contact lens applications. In this study, HA was modified with siloxy or polyethylene glycol moieties using click chemistry to make it more soluble in monomer solutions used to synthesize model contact lens materials; unmodified HA was not soluble in the same monomer solutions. The water contents of the silicone hydrogels were not increased by the presence of modified HA, nor was there a decrease in the surface contact angle. However, modified HA did lead to a reduction in lysozyme adsorption in some cases. The leaching rate of HA modified with polyethylene glycol from a 78:22 DMA:TRIS(OH) hydrogel was significantly slower than for unmodified HA., (© 2014 Wiley Periodicals, Inc.)

Purpose: The aim of this study was to analyze the influence of different lens care systems in surface roughness and refractive index (RI) of contact lenses (CL). This information provides us with a better understanding of how care solutions affect CL materials., Methods: Several CL and three commercially available and appropriate lens care solutions were used (two polyhexamethylene biguanide and one hydrogen peroxide care systems). Lenses were immersed in the lens care systems, and then measurements with CLR 12-70 digital automated refractometer and atomic force microscopy analysis on Tapping mode were recorded. The measurements were performed before and after the lenses were immersed in each care solution., Results: Significant changes were observed on the CL materials when exposed to lens care systems. All the materials changed, to a greater or lesser extent, their roughness and RI, after being immersed in the different solutions. The water content varied between 0% (Nelfilcon A in ReNu Multiplus, Senofilcon A in AOSEPT Plus, and Methafilcon A in Solocare Aqua) and 4.1% (Hilafilcon B in Solocare Aqua) The higher change in roughness was obtained with ReNu Multiplus in the lens Comfilcon A (with an increase of 27.2 nm) and Senofilcon A (with an increase of 16.7 nm)., Conclusion: This study suggests that lens care systems play an important role in surface roughness and RI of CL.

Purpose: To determine the rates of microbial contamination and identify contaminants associated with contact lens (CL) care accessories. To investigate self-reported compliance levels with care of CL accessories and its association with contamination level., Methods: A total of 46 CL cases and care solutions from asymptomatic soft contact lens wearers were collected. Samples from the CL cases and care solutions were cultured for microbiological identification and enumeration. A questionnaire regarding compliance to care and hygiene procedures were administered to each subject on their visit., Results: The percentage of microbial contamination for CL cases and care solutions was 50% and 10.9%, respectively. All the contaminants were bacterial. Staphylococcus aureus (37.0%, 17 of 46 cases) and Escherichia coli (8.7%, 4 of 46 cases) were the most common microorganisms detected in CL cases. In care solutions, S. aureus (8.7%, 4 of 46 samples), Pseudomonas aeruginosa (2.2%, 1 of 46 samples) were common contaminants. CL cases and care solutions that were used for <3 months were significantly less contaminated than those used for >3 months (10.9% versus 39.1%, p<0.05). Polyquad and Aldox based MPS solution showed no contamination. Subjects with medium or low compliance had highly significant rates of contaminations both in CL cases and solutions than for subjects with high compliance (p<0.05)., Conclusions: Nepalese Soft CL wearers are at high risk of developing ocular complications due to high CL case and solution contamination. Frequent replacement of CL cases and solutions, as well as good compliance is recommended to reduce risk of contamination., (Copyright © 2013 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.)

Background: A population-based, cross-sectional telephone survey was conducted to estimate the penetrance and characteristics of contact lens wear in Australia., Methods: Based on postcode distribution, 42,749 households around Australia were randomly selected from the national electronic telephone directory. During calls, the number of individuals and contact lens wearers in each household aged between 15 and 64 years was ascertained. Contact lens wearers were interviewed using a structured questionnaire, to determine details of demographics, lens type, mode of lens wear and hygienic habits. Contact lens wear characteristics and habits were compared by lens type and mode of use., Results: Of the 32,405 households contacted, 19,171 (59.2 per cent) agreed to participate. The penetrance of contact lens wear during the study period was 5.01 per cent (95% CI: 4.78-5.24). The mean age of lens wearers was 36.5 ± 18.3 years and 63.4 per cent were female. There were significant differences in the habits and characteristics of lens wearers depending on their lens type and mode of use., Conclusions: The penetrance of contact lens wear concurs with market estimates and equates to approximately 680,000 contact lens wearers aged between 15 and 64 years in Australia. This is the most detailed and extensive population-based survey of contact lens wearers ever conducted. The discrepancies found between the characteristics of lens wearers surveyed in this study compared to those in previous studies of contact lens practitioners highlights the importance of study design. These results may be applied to other regions with similar health-care and regulatory systems., (© 2013 The Authors. Clinical and Experimental Optometry © 2013 Optometrists Association Australia.)

Background: Significant levels of non-compliance and poor hygiene among contact lens wearers have been reported previously from different parts of the world. This survey aimed at identifying the scope of hygiene and non-compliant behaviour of soft contact lens wearers in the Maldives., Methods: Established soft lens wearers attending two eye clinics in Male' city, were interviewed in office or via telephone. A set of interviewer-administered questions was used to access the subjective response on compliance and hygiene behaviour (hand and lens case hygiene, water exposure, adherence to lens replacement schedule, dozing and overnight wear, awareness of aftercare visits and reuse of disinfecting solution). Participants were also asked to rate themselves as a contact lens user based on their perceived compliance and hygiene practices., Results: Out of 107 participants, 79 (74.8 per cent) were interviewed in the office and the rest via telephone. The majority of lens wearers were female, office workers and students, with a mean age of 20.64 ± 4.4 years. Mean duration of lens wear was 28.04 ± 8.36 months. Most of them were using spherical lenses (86.9 per cent) on a daily wear basis (96.3 per cent). Major reported forms of non-compliance were poor hand hygiene (60.7 per cent), lack of aftercare awareness (39.3 per cent), water exposure (35.5 per cent) and over-use of lenses (24.3 per cent). While females were more likely to overuse their lenses than males (p < 0.005), other socio-demographic factors were not associated with reported non-compliance. Although around 90 per cent of the participants considered themselves average or good contact lens wearers, most exhibited some form of non-compliant and poor hygienic behaviour., Conclusion: A significant number of Maldivian contact lens wearers exhibited poor levels of hygiene and compliance with contact lenses and lens care systems. An effective educational reinforcement strategy needs to be developed to modify lens wearers' non-compliance., (© 2013 The Authors. Clinical and Experimental Optometry © 2013 Optometrists Association Australia.)

Contact lens-associated Acanthamoeba keratitis continues to be a significant cause of visual morbidity in the United States. Although exposure to water sources while wearing lenses has been a known risk factor for infection for decades, this behavior in several contact lens hygiene protocols continues to prevail. In this review, we surveyed the currently available contact lens cleaning solutions for both soft and rigid gas-permeable contact lenses and reviewed the cleaning instructions of the available solutions. Discrepancies between clinician recommendations and written instructions on a solution packages continues to persist, and we advocate a revision in current manufacturer guidelines to include explicit warnings against use of tap or distilled water sources for cleaning contact lenses or their storage cases.

To investigate the bacterial contamination of preservative solutions for contact lenses, contact lens cases were swabbed and the swabs were cultured. Various bacteria were isolated from 26 of 100 samples (26.0%). By preservative solution, the bacterial presence was low (16.7%) in the 30 samples from cases using ReNu, which was the most frequently employed solution, and 27.3% in 11 samples from cases using Complete, which was the second most frequently employed solution. Of 34 strains isolated and identified, gram-negative bacilli-glucose non-fermenting bacteria were the most frequently isolated, accounting for 61.8% (21 strains); particularly, 10 isolates were Stenotrophomonas maltophilia, accounting for 29.4%. The biofilm-forming ability of these isolates was investigated by staining. The mean absorbance of the gram-negative rods was 0.369, which was about 3 times higher than that (0.107) of the Staphylococcus group, confirming marked biofilm-forming ability. In addition, the bactericidal effects of the preservative solutions on the isolates were investigated. The effect varied among the preservative solutions in the suspension experiment, but the highest disinfection rate, which was achieved by Complete, was 99.9->99.99%, showing a favorable bactericidal effect. In contrast, none of the 3 test preservative solutions showed any bactericidal effect in the adhesion experiment.

Purpose: A contact lens (CL) can act as a vector for microorganisms to adhere to and transfer to the ocular surface. Commensal microorganisms that uneventfully cohabitate on lid margins and conjunctivae and potential pathogens that are found transiently on the ocular surface can inoculate CLs in vivo. In the presence of reduced tissue resistance, these resident microorganisms or transient pathogens can invade and colonize the cornea or conjunctiva to produce inflammation or infection., Methods: The literature was reviewed and used to summarize the findings over the last 30 years on the identification, enumeration, and classification of microorganisms adherent to CLs and their accessories during the course of normal wear and to hypothesize the role that these microorganisms play in CL infection and inflammation., Results: Lens handling greatly increases the incidence of lens contamination, and the ocular surface has a tremendous ability to destroy organisms. However, even when removed aseptically from the eye, more than half of lenses are found to harbor microorganisms, almost exclusively bacteria. Coagulase-negative Staphylococci are most commonly cultured from worn lenses; however, approximately 10% of lenses harbor Gram-negative and highly pathogenic species, even in asymptomatic subjects. In storage cases, the incidence of positive microbial bioburden is also typically greater than 50%. All types of care solutions can become contaminated, including up to 30% of preserved products., Conclusions: The process of CL-related microbial keratitis and inflammation is thought to be preceded by the presence or transfer or both of microorganisms from the lens to the ocular surface. Thus, this detailed understanding of lens-related bioburden is important in the understanding of factors associated with infectious and inflammatory complications. Promising mechanisms to prevent bacterial colonization on lenses and lens cases are forthcoming, which may decrease the incidence of microbially driven CL complications.

Introduction: This study investigated the modality, type and duration of contact lens wear as well as compliance and hygiene related issues (hand and case hygiene, use of tap water, dozing and overnight wear) in the UK and Germany. Questionnaires were collected anonymously from 417 UK and 767 German patients attending optometric practices for contact lens appointments. It is the seventh of a series of contact lens wearer profiles conducted since 2000., Results: The proportion of rigid gas permeable lenses worn was significantly higher at 55.4% in Germany, compared to 16.1% in the UK. Overall, a significantly larger proportion of German participants used tap water to rinse their lenses and cases (P<0.001). Also, German respondents changed their lens cases less frequently (p<0.001). Fewer UK than German respondents stated they washed their hands before lens insertion (p=0.009), removal (p=0.01), before eating (p<0.001). German participants were less likely to wash their hands before preparing food (p=0.042) and after using the toilet (p=0.002). The two sample groups differed significantly regarding the care regimens they used for their CLs (p<0.001)., Conclusion: The differences between Germany and the UK highlighted in this study were caused by differences in legal regulations, plumbing and practitioners' guidance. Although many of the questions relating to hygiene differed statistically between the two participating sample groups, the absolute differences in figures were not considered to be large.

Objective: To study the morphological characteristics of genus Acanthamoeba which is an opportunistic organism associated with wearing contact lenses that the biofilm phenomenon in contact lens cases contained Acanthamoeba causing keratitis by conventional culture technique., Material and Method: A total of 150 contact lens cases were biofilm scraped in March till September 2007, at an institution in Nakhornpathom Province, Thailand. The 'gold standard' culture technique was used for the excystation growth development observation. Cysts of Acanthamoeba spp. contained 50 microlitres of Escherichia coli and contact lens solution were incubated and observed for the presence of cysts and/or trophozoites for 12 days. An infected slide was stained with giemsa solution and other non-stained and non-fixed slides were carried out for morphological characteristics study by different microscopes., Results: The prevalence of Acanthamoeba spp. in scraping of contact lens cases was 6.7% (10/150). These Acanthamoeba isolates at temperature around 37 degrees C were consisted of all three groups, which in summary; the average diameter of cysts in Astronyxids (group I) was relatively large. They were > or = 18 micrometers, while those of Polyphagids (group II) and Culbertsonids (group III) were < or = 18 micron. The typical morphology of Acanthamoeba trophozoites moving freely in water were recognized by the presence of lobopodium and acanthopodia within 12 observed days. The average size of Acanthamoeba trophozoites was in the range of 12-45 micron. Three different images of cyst were feature studied., Conclusion: Three Acanthamoeba groups by biofilm scraping from contact lens cases should be differentiated. Morphological characteristics cysts and trophozoites should be confirmed. In addition, to improve contact lens wearer education, compliance with contact lens cases, hygiene recommendations and regular disposal of contact lens cases might help to solve contact lens cases.

Purpose: To determine the impact of the rinse step in "no rub" contact lens care systems relative to its ability to assist in removing loosely associated and bound tear film proteins from a worn silicone hydrogel lens., Methods: After informed consent, subjects were fitted with lotrafilcon B contact lenses (CIBA Vision). If the fit was acceptable, subjects were asked to wear the lenses on a daily wear basis for 5 (+2, -0) days for an outcome visit. Subjects were instructed to use AQuify Multi-Purpose Disinfecting Solution (CIBA Vision) following the manufacturer's "no rub" instructions. At the outcome visit, contact lenses were then collected by a gloved examiner, with a sterile metal forceps, who rinsed the right lens but did not rinse the left lens on removal from the eyes. Protein was extracted with a 50:50 0.2% trifluoroacetic acid-acetonitrile solution and quantified using a Bradford analyses., Results: Twenty contact lens wearers were enrolled in this study. For the non-rinsed lenses, the first extraction yielded 13.4 +/- 9.2 microg/lens of protein, whereas the second extraction yielded 5.8 +/- 2.8 microg/lens of protein. For the rinsed lenses, the first extraction yielded an average of 3.0 +/- 1.9 microg/lens of protein, whereas the second extraction yielded an average of 4.0 +/- 2.3 microg/lens. Repeated measures analysis of variance showed a significant interaction (F-statistic = 18.9, p < 0.0001) between the rinse of a lens and extraction number., Conclusions: Rinsing a contact lens after removal from the eye removes well more than one-half of the protein associated with it. Further, to biochemically recover all protein from a silicone hydrogel lens, it may be important to perform more than one chemical extraction from it.

A variety of approaches are available for cleaning, rinsing, disinfecting and storing reusable soft contact lenses. As demonstrated in this report of the results of annual UK prescribing surveys conducted over the past 12 years, there has been a steady increase in the use of multi-purpose solutions, which in 2007 represented 93% of all lens care systems prescribed. This increase is attributed to factors such as simplicity, reduced cost and enhanced compliance with these products. The apparent reversal of this trend in 2008 is probably due to an undermining of patient and practitioner confidence in multi-purpose solutions relating to withdrawals of some multi-purpose solutions from the market, and controversies concerning corneal staining with some lens-solution combinations.

Purpose: The purpose of this study is to assess corneal staining and subjective symptom ratings with six different silicone hydrogel contact lens/multipurpose solution combinations, including the recently launched Menicon PremiO silicone hydrogel contact lens, after the first night of soaking the lenses in solution., Methods: This study is a prospective, single-centre, subject-masked, contralateral, crossover, daily wear clinical trial in which subjects were randomly fitted in the morning with a different lens/solution combination in each eye, asked to wear the lenses for the whole day (at least 12 h), soak each of the lenses overnight in one of the test solutions and insert the lenses on the following morning. Subjects were asked to come on that morning for assessment of corneal staining and subjective ratings. All subjects repeated this procedure on another two occasions in order to collect the results of the six different lens/solution combinations: Menicon PremiO/MeniCare Soft; Menicon PremiO/Complete 10; Menicon PremiO/OptiFree Express; Acuvue Oasys/MeniCare Soft; Acuvue Oasys/Complete 10; Acuvue Oasys/OptiFree Express., Results: Menicon PremiO lenses were associated with a lower level of corneal staining overall, and in the nasal and temporal locations, compared with Acuvue Oasys lenses (p < 0.05). No significant differences were found in corneal staining between solutions (p > 0.05). An overall rate of solution-induced corneal staining per eye of 12% was found. Symptoms were very similar among the six different lens/solution combinations (p > 0.05)., Discussion: The lower level of corneal staining found with Menicon PremiO lenses compared with Acuvue Oasys lenses might be attributed to material, surface and design differences between lens types. The overall rate of solution-induced corneal staining and symptomatology found between the different lens/solutions combinations is consistent with previous studies.

In May 2006, the Illinois Department of Public Health (IDPH) informed CDC about a possible increase in Acanthamoeba keratitis (AK) at an ophthalmology center in Illinois during the preceding 3 years. The University of Illinois at Chicago (UIC) was investigating this possible increase. In October 2006, IDPH updated CDC about the ongoing UIC investigation. At that time, CDC informally contacted multiple ophthalmology centers in the United States to assess whether the potential increase in cases extended beyond Illinois. Responses from the ophthalmology centers were inconclusive. In January 2007, CDC initiated a retrospective survey of 22 ophthalmology centers nationwide to assess whether cases were increasing throughout the United States. In March 2007, data received from 13 centers demonstrated an increase in culture-confirmed cases of AK with wide geographic distribution. The increase in cases had begun in 2004 and continued to the present. On March 16, 2007, CDC initiated a multistate investigation to look for risk factors associated with this increase in AK cases. This report summarizes recent preliminary results of that investigation, which, indicated an association with AK in soft contact lens wearers who used Advanced Medical Optics (Santa Ana, California) Complete MoisturePlus (AMOCMP) multipurpose cleaning solution. CDC and the Food and Drug Administration (FDA) are taking steps to notify the public and the medical and public health communities of this preliminary association. The manufacturer has undertaken a voluntary recall of the product.

Purpose: The aims were to determine the level of compliance of contact lens wearers, to identify which procedures have highest levels of non-compliance and to study the effectiveness of a compliance enhancement strategy on the level of compliance., Methods: The level of compliance for each subject was evaluated with a self-administered questionnaire together with microbiological examination of their contact lenses, lens cases and lens care solutions. The effect of an intervention to improve the level of compliance was determined by a controlled trial. A regular self-review exercise on proper lens handling was given to the test group once every three months for 12 months. The levels of compliance and contamination of contact lenses and lens care accessories between test and control groups were compared at the end of the 12-month period to evaluate the effect of the intervention., Results: Sixty-five subjects who were experienced contact lens wearers were recruited and 60 completed the study. All showed some degree of non-compliance in the care of their contact lenses and lens accessories. Most (about 60 per cent) were non-compliant with at least six of a total of 15 lens care procedures. The most common non-compliant behaviour among contact lens wearers was associated with the care of the lens case. By the end of the study period, our compliance enhancement strategy did not appear to have had a significant effect on the behaviour of our subjects, except for improvement in the care of lens cases. Compliance for other procedures improved in both test and control groups., Conclusion: All subjects showed some degree of non-compliance and the spectrum of non-compliance was wide. The poorest levels of compliance were associated with care of the lens case, which was also the most frequently contaminated item. Our compliance enhancement strategy showed a significant difference in improvement in compliance between the intervention and control groups only in the care of lens cases.

A total of 90 subjects were investigated in this study, out of which 51 constituted the contact lens wearing group and 39 constituted the control group who had never worn contact lenses. Out of 51 contact lens wearing group, 41 were asymptomatic lens wearer subjects and 10 were symptomatic lens wearer subjects having some complications. All the subjects of contact lens wearing group had worn soft contact lenses on daily wear basis for a duration of 7 days to one year. In total 33 subjects were culture positive and remaining 57 culture negative. Staphylococcus epidermidis was isolated equally from asymptomatic and control group, however, significantly more gram negative organisms such as Pseudomonas aeruginosa and Serratia marcescens were isolated from the symptomatic lens wearers. P. aeruginosa and S. marcescens could also be isolated from lens storage cases. S. marcescens was the organism most commonly isolated from the contact lens solutions. Further, the results showed that both P. aeruginosa and S. marcescens adhere to injured cornea only and not to normal cornea when microscopic study of adherence of bacteria to uninjured and injured ex vivo mouse corneas was done.

Purpose: To analyze factors implicating the association of ReNu with MoistureLoc (ReNu ML) multipurpose contact lens solution (MPS) with the increased incidence of Fusarium keratitis., Methods: Used contact lens cases with and without contact lenses and MPS containers were collected from patients with confirmed or possible Fusarium keratitis. Direct microscopy including transparent adhesive tape preparations and swab cultures were used to determine fungal colonization. Survival and growth of selected isolates of Fusarium spp. in drying MPS on plastic surfaces were determined by microscopy and recoverable colony counts on enriched agar., Results: Discrete regions of fungal colonization, including occasional microcycle conidiation and chlamydospore formation, were observed on the surfaces of contact lens cases and, less often, on solution containers that had been used by patients with Fusarium keratitis associated with the use of ReNu ML. Isolates provisionally grouped with the F. solani-F. oxysporum complex were inhibited by fresh MPS in original solution containers and contact lens cases, but survived in stressed (drying) films of MPS, particularly ReNu ML. These in vitro test results were similar to the direct in situ observations of the materials from patients., Conclusions: Selective, rapid growth and survival of cells of the F. solani-F. oxysporum complex on plastic surfaces, particularly of contact lens cases with stressed ReNu ML films, may explain, in part, the recent Fusarium keratitis outbreak.

Context: Fusarium keratitis is a serious corneal infection, most commonly associated with corneal injury. Beginning in March 2006, the Centers for Disease Control and Prevention received multiple reports of Fusarium keratitis among contact lens wearers., Objective: To define the specific activities, contact lens hygiene practices, or products associated with this outbreak., Design, Setting, and Participants: Epidemiological investigation of Fusarium keratitis occurring in the United States. A confirmed case was defined as keratitis with illness onset after June 1, 2005, with no history of recent ocular trauma and a corneal culture growing Fusarium species. Data were obtained by patient and ophthalmologist interviews for case patients and neighborhood-matched controls by trained personnel. Available Fusarium isolates from patients' clinical and environmental specimens were genotyped by multilocus sequence typing. Environmental sampling for Fusarium was conducted at a contact lens solution manufacturing plant., Main Outcome Measures: Keratitis infection with Fusarium species., Results: As of June 30, 2006, we identified 164 confirmed case patients in 33 states and 1 US territory. Median age was 41 years (range, 12-83 years). Corneal transplantation was required or planned in 55 (34%). One hundred fifty-four (94%) of the confirmed case patients wore soft contact lenses. Forty-five case patients and 78 controls were included in the case-control study. Case patients were significantly more likely than controls to report using a specific contact lens solution, ReNu with MoistureLoc (69% vs 15%; odds ratio, 13.3; 95% confidence interval, 3.1-119.5). The prevalence of reported use of ReNu MultiPlus solution was similar between case patients and controls (18% vs 20%; odds ratio, 0.7; 95% confidence interval, 0.2-2.8). Fusarium was not recovered from the factory, warehouse, solution filtrate, or unopened solution bottles; production of implicated lots was not clustered in time. Among 39 isolates tested, at least 10 different Fusarium species were identified, comprising 19 unique multilocus genotypes., Conclusions: The findings from this investigation indicate that this outbreak of Fusarium keratitis was associated with use of ReNu with MoistureLoc contact lens solution. Contact lens users should not use ReNu with MoistureLoc.

Objective: Testing the protein-removing effect of the protein-removing care solution on the protein precipitation of the soft contact lenses., Method: Soak the lenses into the artificial-tears to simulate the protein absorption, test the absorbency of cleaned protein at the wavelength of 280 nm by UV spectrophotometer, and compute the percentage of protein., Result: Testing results of the percentage of the cleaned protein are repeatable., Conclusion: This experimental method can be used to evaluate the cleaning effect of the protein- removing care solution, but still needs much improvements.

Purpose: To evaluate and compare changes to the back optic zone radii (BOZR) and the level of surface scratches of Menicon rigid gas-permeable (RGP) lenses in and between palm and digital cleaning methods and to determine whether these changes are affected by different examiners, lens materials, and initial BOZR., Methods: Ninety-six Menicon RGP lenses of two different lens materials (Menicon Z and Menicon EX) and of initial BOZR 7.6 and 8.1 mm were cleaned by two independent examiners using either palm or digital cleaning methods for a total of 270 times (simulating 9 months' use). The study was conducted with the examiners masked as to the initial BOZR and the lens material of each lens. The two examiners who investigated the BOZR and the lens surfaces were also unaware of the method of cleaning used on each lens. The BOZR and the level of scratches on lens surfaces were determined before initiating lens rubbing and after every 2 simulated months (60 cleanings) for 8 simulated months and again at the ninth simulated cleaning month., Results: No lens warpage was observed in any of the lenses cleaned with either method. We found no clinically significant changes in the BOZR with the number of cleanings between palm and digital cleaning methods for both the steep and the flat lenses. Changes to the BOZR were also unaffected by the examiners and the lens types. The overall mean +/- SD changes in BOZR (from baseline) after 9 simulated months were -0.014 +/- 0.025 mm for lenses using palm cleaning and -0.010 +/- 0.022 mm for lenses using digital cleaning. The level of scratches on the lenses was dependent on the examiners and the number of cleanings but was unaffected by the method of cleaning, the lens type, and the initial BOZR of the lenses. The level of scratches increased with the number of cleanings, and the median level of scratches (range) observed after 9 simulated cleaning months was grade 1.0 (0.50 to 1.50) for examiner 1 and grade 1.50 (0.50 to 2.00) for examiner 2. These values were, however, not clinically significant., Conclusions: Palm or digital cleaning of Menicon RGP lenses for 9 simulated months of cleaning did not lead to any lens warpage. Changes to the BOZR with the number of cleaning were not clinically significant with either method of cleaning. Methods of cleaning, different examiners following the same procedures, lens types, and initial BOZR did not affect BOZR changes. The level of surface scratches was only dependent on the examiners and the number of cleanings. However, the changes observed were not clinically significant. Because the levels of change to the BOZR and surface scratches were comparable for both palm and digital methods of cleaning, these lenses may be cleaned using either cleaning method.

Purpose: To test the design of a patient care regimen for soft lenses that aims to provide the highest standards of disinfecting through use of domestic microwave cookers, while also providing storage equipment and solution that enable patients to follow a conventional cold disinfecting regimen when traveling. The cleaning efficacy of surfactant agents during microwave treatment was also considered., Methods: The microbiologic performance of the regimen and its disinfecting apparatus was tested according to the Food and Drug Administration (FDA) protocols for contact lens heat disinfectors. Subsequently, a prospective pilot clinical trial of the regimen involving 15 subjects was carried out to the protocols of the FDA and International Standards Organization 11,980:1997., Results: Lenses inoculated with 10(7) colony-forming units (cfu) of Enterococcus faecalis were disinfected to 0 cfu by a 12-s irradiation of a compact disinfecting case that held the lenses suspended in 12 ml saline. A proof of operation indicator performed correctly for all 10 cases tested. No adverse reactions were found in the pilot patient trial, using Renu multipurpose (Bausch and Lomb, Rochester, NY) as the test solution, and no statistically significant difference was found between test and control groups in respect of any sign. However, the greater incidence of edema, palpebral hyperemia, and lens front-surface deposition in the microwave test group may be clinically significant., Conclusions: The design of the test care regimen proved easy for patients to follow in either hot or cold disinfecting mode. The greater incidence of certain signs in the microwave test group suggests the need to continue using a rub and rinse step for the microwave mode and for additional investigation into the choice of an appropriate multipurpose solution formulation for this proposed regimen, preferably one that does not use a block copolymer-type surfactant agent.

Purpose: To determine the effect of storage time and temperature on the efficacy of four multipurpose solutions for soft contact lenses., Method: Aliquots of multipurpose solutions (OPTI-FREE Express, ReNu MultiPlus, COMPLETE and SOLO-care) stored at different temperatures over a 3-month period, were challenged with contact lens-related ocular pathogens, Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans., Results: The results showed that OPTI-FREE Express had the best activity against Ps. aeruginosa at all temperatures; ReNu MultiPlus performed well at 25 degrees C; COMPLETE barely achieved activity requirements at all temperatures, and lost efficacy after 2 months. SOLO-care maintained its activity best against Ps. aeruginosa at 30 degrees C. Storage at fridge temperature reduced activity of all solutions. Regardless of storage temperature, activities of all solutions against S. aureus markedly decreased by 2 months. Only OPTI-FREE Express met FDA requirements against C. albicans., Conclusion: Performance of multipurpose solutions is affected by time and temperature of storage. Contact lens users should be aware that the efficacy of opened solutions may not be sustained for as long as 3 months. Manufacturers should reconsider their recommendations to further safeguard the ocular health of contact lens wearers.

Purpose: The PuriLens contact lens system is indicated for cleaning and disinfection of soft (hydrophilic) contact lenses by means of subsonic agitation to remove lens deposits and microorganisms, and ultraviolet irradiation of the storage solution for disinfection. The capacity of the PuriLens system to disinfect storage solutions contaminated with known concentrations of Staphylococcus aureus, Pseudomonas aeruginosa, and Acanthamoeba species was evaluated., Methods: An in vitro assessment of the antibacterial and antiparasitic efficacy of the PuriLens system was performed. Separated batches of the storage solution for the cleansing system were contaminated with stock strains of S. aureus and P. aeruginosa. A comparison of the microbiologic content was made between the solution before and after the cycle., Results: The PuriLens system effectively eradicated S. aureus and P. aeruginosa organisms after a 15-minute cycle. However, viable cysts of acanthamoeba were recovered in the solution after the 15-minute cycle., Conclusions: The PuriLens system is highly efficient in protecting against contamination with common bacterial ocular pathogens. Acanthamoeba cysts, however, can survive in the solution or contact lens bath undergoing integrated subsonic debridement and indirect ultraviolet light disinfection. Use of chemical disinfecting solutions that contain agents such as chlorhexidine or other cationic antiseptics may be advisable in conjunction with use of the PuriLens device, especially in high-risk settings.