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Purpose: To determine the antimicrobial efficacy of a povidone-iodine system (PVP-I; cleadew, OPHTECS Corporation, Kobe, Japan), a peroxide system (AOSEPT Plus with HydraGlyde, Alcon, Fort Worth, TX), and a chemical multipurpose system (renu fresh, Bausch & Lomb, Rochester, NY) on contact lens case surfaces that are both in contact and not in contact with the solutions during lens disinfection.Methods: The surfaces of the inner walls, underside of the lid, and lens holder (if applicable) of the cases were inoculated with P. aeruginosa ATCC 27853. The cases were disinfected with the solutions as per their manufacturer instructions. After disinfection, the inoculated surfaces were swabbed and the amount of surviving P. aeruginosa was determined. Following this experiment, separate cases were inoculated and disinfected as before. This time the cases were agitated after recommended disinfection time and the amount of P. aeruginosa in the disinfecting solution was quantified immediately, and again after resting for 7 days. Experiments were conducted in triplicate (n = 3).Results: Units are expressed in log CFU. All three solutions significantly reduced P. aeruginosa on direct-contact surfaces (all p < 0.039). On non-contact surfaces, the reduction of P. aeruginosa in the PVP-I system (pre-disinfection: 6.8 ± 0.5, post-disinfection: 1.0 ± 0.0; p < 0.001) was significant, but not for the hydrogen peroxide system (pre-disinfection: 6.3 ± 0.6, post: 5.5 ± 0.5; p = 0.194) and the chemical multipurpose system (pre-disinfection: 6.6 ± 0.1, post-disinfection: 5.6 ± 0.8; p = 0.336). After 7 days post-disinfection, no P. aeruginosa regrowth was observed in the PVP-I system (Day 1: 1.0 ± 0.0, Day 7: 1.0 ± 0.0; p = 1) and the chemical multipurpose system (Day 1: 4.2 ± 0.2, Day 7: 1.8 ± 0.9; p = 0.012), however regrowth was observed in the hydrogen peroxide system (Day 1: 3.4 ± 0.6, Day 7: 6.1 ± 0.4; p = 0.003).Conclusion: The PVP-I system was more effective against P. aeruginosa on non-contact surfaces than the hydrogen peroxide system or the chemical multipurpose system and is capable of inhibiting regrowth of P. aeruginosa for at least 7 days post-disinfection. [ABSTRACT FROM AUTHOR]

Background: Contact lens care regimens appear to be prescribed based on familiarity or by matching contact lens brands rather than consideration to efficacy. Aim: This study compared the effectiveness of multipurpose and peroxide cleaning solutions on low- and high-water content ionic and non-ionic soft contact lenses, in removing Pseudomonas aeruginosa (P. aeruginosa). Setting: The laboratory work was conducted by health science students in a graduate level programme in the microbiology laboratory at a university in south-eastern South Africa. Methods: A quantitative analytical experimental design was used. Four groups (labelled I, II, III and IV) of soft contact lenses, varied ionicity and water content were inoculated with P. aeruginosa and then exposed to three solutions containing antimicrobial ingredients, polyaminopropyl biguanide (Dymed), hydrogen peroxide (H2O2) and polyquaternium-1 (Polyquad). Each group contained 14 soft contact lenses, with the exception of Group III in which eight lenses were used. Saline served as the control. After 18 h, the remaining colony-forming units were counted using visual inspection as an indicator of efficacy against P. aeruginosa. Results: The solution containing H2O2 was found to be the most effective in removing P. aeruginosa from all Food and Drug Administration (FDA) groups of contact lenses whilst Dymed was found to be comparatively ineffective for this organism. Water content and ionicity had no effect on the efficacy of the solutions. Conclusion: Practitioners should consider the efficacy of the active ingredients against microorganisms when dispensing contact lens solutions, particularly for contact lens wearers at risk for P. aeruginosa infections. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Purpose: To review contact lens prescribing trends in Japan between 2003 and 2016.Methods: An annual survey of contact lens prescribing trends was conducted each year between 2003 and 2016. Japanese ophthalmologists were asked to provide information relating to ten consecutive contact lens fittings between January and March every year.Results: Over the 14 years of the annual survey, data from a total of 64,122 contact lens fits were returned by ophthalmologists. The mean age (±SD) of lens wearers was 30 ± 13 years, and 68% were female. The proportion of rigid lens fits decreased over time, from 35.4% in 2003 to 14.7% in 2016. Across this period, daily disposable lens fits increased, representing 46% in 2016. The proportion of toric lenses and multifocal lenses gradually increased, from 6.6% and 1.9% to 12.3% and 5.8%, respectively. Silicone hydrogel material use grew from 0% to 43.2%, while mid and low water content lens materials declined from 54.1% and 28.2% to 36.1% and 8.3%, respectively. Multi-purpose lens care solutions dominated the market over the 14 year survey period.Conclusions: This survey has revealed prescribing trends and preferences in Japan over the past 14 years, with the main changes observed being a decrease in rigid lens use and an increase in the use of silicone hydrogel materials and daily disposable lenses. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Acanthamoeba keratitis is commonly encountered by contact lens wearers. Contact lens solution plays an important role in the safe use of contact lenses. The most popular products for disinfecting lenses are multipurpose disinfecting solutions (MPDS). However, almost all MPDS retailed in Korea are ineffective in killing Acanthamoeba . The objective of this study was to determine the possibility of using autophagy inhibitor chloroquine as a disinfecting agent to improve the amoebicidal activity of MPDS against Acanthamoeba, especially the cyst. Amoebicidal effects of eight different MPDSs combined with chloroquine (CQ), an autophagy inhibitor, and their cytotoxicities to human corneal epithelium cells were determined. Almost all MPDS showed strong amoebicidal effect on trophozoites after 8 h of exposure. However, they showed inadequate amoebicidal effect on cysts even after 24 h of exposure. MPDSs combined with 100 μM CQ increased their amoebicidal effects on immature cyst by inhibiting formation of mature cysts. Incubation with 100 μM CQ for 30 min did not have cytotoxicity to human corneal epithelial cells. [ABSTRACT FROM AUTHOR]

Purpose To assess the quality of life in French keratoconus patients. Setting Fifty-seven Keratoconus National Reference Centers across France. Design Prospective case series. Methods Patients completed the National Eye Institute Visual Functioning Questionnaire-25 (NEI VFQ-25) and a French validated questionnaire on disability and dependency from February to June 2012 when they came for an ophthalmic examination at 57 participating centers across France. An ocular examination including refraction, corneal topography, pachymetry, and slitlamp biomicroscopy was performed. The composite or global NEI VFQ-25 score and the proportion of patients who were dependent (defined by the difficulties with activities of daily living) because of keratoconus were the main evaluation criteria in this study. Results The study comprised 550 keratoconus patients. Women, corrected distance visual acuity worse than 20/40, steep keratometry higher than 52.0 diopters, history of surgery (corneal transplant, intrastromal corneal ring segments, or corneal crosslinking), and more severe keratoconus according to the Amsler-Krumeich classification were associated with an increasingly negative impact on quality of life (overall scores are significantly lower). Moreover, 4.9% of participants reported having changed their jobs because of keratoconus and 7.8% received keratoconus-related disability. Sixty-nine (12.5%) patients reported having difficulties with activities of daily living and are considered dependent. Conclusion Keratoconus was associated with a significant reduction in quality of life but it did not result in social exclusion. [ABSTRACT FROM AUTHOR]

In this study, the efficacy of two recently marketed multipurpose contact lens disinfecting solutions against Staphylococcus aureus Rosenbach and Pseudomonas aeruginosa Gessard bacteria isolated from clinical specimens were investigated. The antibacterial activities of multipurpose contact lens disinfecting solutions were determined by microbiological culture method described in ISO 14729 guidelines. Bacterial counts were obtained for sampling intervals determined in addition to the manufacturer's minimum recommended disinfection time and mean log reductions were calculated for each interval. Three different lots of each contact lens disinfecting solutions were used. The results showed that both contact lens disinfecting solutions provided at least 3 log reductions for all bacteria tested at the end of the manufacturer's minimum recommended disinfection time. New formulations are being developed in contact lens disinfecting solution industry by new technologies and scientific researches. Further studies on strains isolated from different sources are needed in order to a complete understanding of these newly marketed contact lens solutions. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 46-year-old non-atopic woman presented with an itchy reaction involving her left hand and a history of retinal detachment surgery. Topics discussed include attribution of lesions to particular rinse-off contact lens cleaning solution coming into contact with the affected area twice daily, the product contained poly(hexamethylene) biguanide hydrochloride (PHMB) and ability of PHMB to induce allergic contact dermatitis found in contact lens care solutions.

Soft multifocal simultaneous image contact lenses have boomed in recent years due to the growing number of presbyopic patients demanding visual solutions, allowing them to maintain their current standard of living. The concept of 'simultaneous image' is based on blur interpretation and/or blur tolerance of superimposed multiple images on the retina formed by various powers of a contact lens. This is the basis for a specific type of multifocal contact lens developed for the compensation of presbyopia. Manufacturers have released a great variety of soft simultaneous image lens designs to meet different patient needs but their fitting is still unsatisfactory in some cases. Some presbyopes discontinue wearing contact lenses due to some limitations in visual quality and comfort that can be overcome with an appropriate contact lens selection based on a comprehensive pre-fitting evaluation. This paper aims to review the different types of soft multifocal contact lenses that are currently available for presbyopic correction and to define the steps and factors crucial for their fitting, such as pupil, aberrations, accommodation and centring. A discussion about useful tools to achieve a customised fitting leading to a successful outcome, such as the defocus curve, power profile and questionnaires, is performed. [ABSTRACT FROM AUTHOR]

Objectives: To assess the demographic and behavioral profile of patients with optic medical indication of contact lenses (CL) in a public hospital in Curitiba. Methods: Cross-sectional questionnaire study of patients who attended the contact lens service of the national health system (SUS) outpatient clinic from the "Hospital de Olhos do Paraná" between September 2nd, 2014 and August 4th, 2015. Results: Of the 69 people interviewed, 56.52% acquired CL. Of these, 55.07% are between 20-49 years old, 69.56% are women, 40.58% had finished high school and 36.23% earned a salary of 2 to 6 times the minimum wage. Rigid lenses prevailed, representing 66.67% of the total, with less than 8 hours of usage in 41.02% of the cases and discomfort during usage was assessed in 59%. The cleaning of CL was done at the moment of insertion and removal in 87.18% of cases, and 71.8% used contact solution. High purchase cost was the main reason for not using CL for 70% of patients who did not use this resource. Conclusions: Of the patients interviewed, 56.52 % started using LC. Keratoconus was the main disease for which CL were indicated. It was demonstrated in this study that patients in question have good guidance on handling and maintenance of LC. Despite the unquestionable advances in medical technology continue to occur the abandonment of the use of this feature mainly the cost and fear of handling. It is the responsibility of the expert clarify the benefits that patients with medical indication will have with the use of LC, as well as encourage their use. [ABSTRACT FROM AUTHOR]

Purpose To describe dendritiform keratopathy associated with exposure to polyquaternium-1, a common preservative found in contact lens solutions and tear replacement products. Design Case series. Participants Sixteen patients who demonstrated dendritiform keratopathy during topical ophthalmic exposure to polyquaternium-1. Methods Records were reviewed of all patients diagnosed with dendritiform keratopathy between 1999 and 2014 who had documented exposure to contact lens care disinfecting solutions or artificial tear solutions containing polyquaternium-1. Patients were excluded who had coexisting potential causes for dendritiform keratopathy, such as prior herpes simplex keratitis, varicella-zoster viral keratitis, the linear form of Thygeson's superficial keratitis, epithelial regeneration line, Acanthamoeba keratitis, mucus plaque keratopathy, medication-related keratopathy, or limbal stem cell deficiency characterized by conjunctivalization of the corneal epithelium. Main Outcome Measures Effect of discontinuation of exposure to polyquaternium-1 on the dendritiform keratopathy. Results Sixteen patients demonstrated dendritiform keratopathy after exposure to the preservative polyquaternium-1. Thirteen patients had a history of recent exposure to contact lens disinfecting solutions (Opti-Free, Equate) containing polyquaternium-1. Three patients used a tear replacement product (Systane) containing a polyquaternium-1 preservative. Four patients were treated with antiviral medications for presumed herpes simplex keratitis; 4 patients underwent diagnostic testing for Acanthamoeba keratitis. Two additional patients were diagnosed sequentially with herpes simplex keratitis, then Acanthamoeba keratitis before referral. All dendritiform lesions resolved within 2 to 6 weeks after elimination of exposure to polyquaternium-1. Conclusions Ophthalmic products containing polyquaternium-1 may cause dendritiform keratopathy that may be confused with infections of the superficial cornea, such as herpes simplex virus keratitis or Acanthamoeba keratitis. [ABSTRACT FROM AUTHOR]

Background Total or partial loss of tooth structure occured due to caries or trauma. The decayed or fractured tooth is restored with appropriate restorative materials. A range of restorative materials are available in the market today, but each of them has one or the other drawbacks, viz. color mismatch, variable wear resistance, and strength. Therefore, there has always been a quest to use a restorative material which has properties as close to natural tooth as possible. Extracted human teeth have been tried as restorative materials with good success rate, but their storage has been a problem due to change in physical properties. Aims and objectives To evaluate the changes in the mechanical properties of the extracted human teeth to be used as biological restoration upon storing them in different storage media and to compare their effectiveness. Material and methodology Five hundred and twenty extracted human teeth (samples) included in the study were equally distributed and randomly stored in different storage media (saline, artificial saliva, ORS, coconut water, and eye solution), and their mechanical properties were checked at different time intervals (7, 14, and 30 days) using universal testing machine and Vickers hardness test. Result and conclusion None of the storage media used in the study significantly altered mechanical properties of the stored extracted human teeth except the hardness which was substantially reduced after storing for 30 days. Of the 4 media tested, eye solution was found to be the best, while artificial saliva was found to be least effective as storage media. It was also concluded that storage time of the extracted teeth to be used as biological restorations should not exceed more than 3-4 weeks as beyond this time, mechanical properties namely hardness get altered significantly. [ABSTRACT FROM AUTHOR]

Purpose The aim of this study was to assess the antimicrobial effects of marketed contact lens disinfecting solutions. Methods Using ISO 14729 Stand-Alone Test for disinfecting solutions, bactericidal, fungicidal and amoebicidal assays of eight different contact lens solutions including: ReNu MultiPlus, DuraPlus, Ultimate Plus, OptiFree Express, Kontex Clean, Kontex Normal, Kontex Multisol extra + , Kontex Soak were performed. The efficacy of contact lens solutions was determined against keratitis-causing microbes, namely: Pseudomonas aeruginosa , Serratia marcescens , Staphylococcus aureus , Methicillin-resistant Staphylococcus aureus , Fusarium solani and Acanthamoeba castellanii . Results The results revealed that ReNu MultiPlus, DuraPlus and OptiFree Express were effective in killing bacterial and fungal pathogens as per manufacturer's minimum recommended disinfection time. Ultimate Plus was effective against F. solani and MRSA but ineffective against P. aeruginosa , S. marcescens and S. aureus. Of concern however, is that none of the locally formulated contact lens disinfecting solutions from Pakistan, i.e., Kontex Clean, Kontex Normal, Kontex Multisol extra + and Kontex Soak were effective against any of the keratitis-causing organisms tested. All eight contact lens disinfecting solutions were unable to destroy Acanthamoeba cysts. Conclusions Because such ineffective contact lens disinfection solutions present a major risk to public health, these findings are of great concern to the health officials and to the manufacturers of the contact lens disinfection solutions and effective solutions are needed, along with emphasis on proper hygiene for contact lens care and special guidelines for developing countries regarding the manufacture and storage of contact lens disinfecting solutions. [ABSTRACT FROM AUTHOR]

Fungi rarely cause disease outbreaks associated with use of microbe-contaminated drugs. These rare episodes typically involve a restricted spectrum of common environmental species with relatively low virulence, rather than classical pathogens. Review of data involving over-the-counter contact lens solutions and prescription drug-related recalls revealed six episodes during the past decade with significant adverse health and financial impact (including loss of vision and death). Contaminations involved fungi mostly identified with the genera Aspergillus, Exserohilum, Fusarium, Paecilomyces, and Rhizopus. These organisms are noted for their capacity to produce resistant morphotypes (chlamydoconidia, ascospores) under various adverse conditions, generally with temperature survival/tolerances markedly in excess of maximal growth temperatures. High constituent levels of melanin, trehalose and heat-shock proteins facilitate differential survival of morphotypes following exposures to toxic chemicals and temperatures above 80 °C. Adverse environmental factors that induce resistant morphotypes are suggested to occur more readily in situ than during in vitro testing. Rare unexplained, sporadic drug contamination episodes with select thermotolerant fungi may relate, in part, to resistant dormant stages. [ABSTRACT FROM AUTHOR]

Purpose: To document contact lens prescribing trends in the United Kingdom over the past quarter of a century.Methods: An annual survey of contact lens prescribing was conducted each year from 1996 to 2020, inclusive, by asking a random selection of optometrists and contact lens opticians to provide information relating to 10 consecutive contact lens fits between January and March.Results: Over the 25 year survey period, 2,671 practitioners returned survey forms, reporting a total of 25,575 contact lens fits. The mean (± standard deviation) age of lens wearers was 35 ± 15 years, of which 64 % were female. Over the survey period, rigid lens new fits decreased from 22 % to 2%. The prescribing of silicone hydrogel lenses has increased steadily since their introduction towards the end of the 1990s, and now represent 80 % of soft lens fits. Soft toric lens prescribing has gradually increased to 47 % - a value at which astigmatism ≥ 0.75DC is theoretically corrected in all contact lens wearers. Daily disposable prescribing increased steadily over the survey period and now represents 63 % of lenses prescribed. Extended wear fits remain at very low levels, except for some prescribing for overnight orthokeratology. Multi-purpose lens care solutions are ubiquitous; peroxide and other systems are now seldom prescribed. Rigid lenses and monthly replacement soft lenses are predominantly worn on a full time basis, whereas daily disposable soft lenses are mainly worn part time.Conclusions: This report documents the evolution of contact lens fitting in the United Kingdom over the past 25 years. The most likely lens fit is a spherical design silicone hydrogel daily disposable contact lens prescribed for a 35 year old female and worn on a part-time basis. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the susceptibility of different fungal corneal isolates to commercially available contact lens disinfecting solutions. Methods: Thirteen filamentous fungal isolates (9 Aspergillus spp, 3 Fusarium spp, 1 Curvularia sp.) recovered from corneal infections were used. The following solutions were tested: Arion Cronos, Complete Revitalens, Dua Elite, Opti-Free Express, Regard, Oxysept Comfort, and Oxysept Comfort without catalase. Suspensions of the different fungal isolates were made in the solutions (106 colony-forming units/mL). After 1 h (Arion Cronos only), 6, 8, and 24 h, aliquots of suspension were removed and seeded on Sabouraud agar plates. Results: After a 6-h exposure, only 3% hydrogen peroxide-based Oxysept Comfort without catalase eradicated all the fungi tested. All the other solutions were partly ineffective at killing some of the fungal isolates, even after a 24-h exposure. The worst performance was given by Regard and Dua Elite, which, after a 6-h exposure, showed growth of 12 and 10 of the 13 fungal strains tested, respectively. Conclusions: Most contact lens disinfecting solutions may not be sufficiently effective, if contact lens care systems become contaminated with filamentous fungi. In our experiment, only an exposure to 3% hydrogen peroxide without a neutralizer for at least 6 h was always able to kill an inoculum of different fungal strains. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: The aim of this study was to measure the refractive index of three readily available contact lens saline solutions in order that these values could be used in a calculation to convert back vertex power measured in saline to its corresponding power in air. Method: Using an automatic digital refractometer, measurements were made daily for 31 days at 20°C and at a wavelength of 589.3nm of the refractive index of fifteen bottles from different manufacturing batches of each of the three saline solutions. Results: For AMO LENS PLUS™ OcuPure™, BAUSCH & LOMB Sensitive Eyes™ Plus Saline Solution and Sauflon saline, the mean values of refractive index were 1.33458, 1.33465 and 1.33470, respectively. The standard deviation for each solution was 0.00001 and the range of the measured values of refractive index of the three solutions over the test period did not exceed 0.00005. Conclusions: It is proposed that when calculating back vertex power in air from measurements made in a wet cell that refractive index values for AMO LENS PLUS™ OcuPure™, BAUSCH & LOMB Sensitive Eyes™ Plus Saline Solution and Sauflon saline of 1.3347, 1.3348 and 1.3348, respectively be used for focimeters operating at a wavelength of 587.56nm and values of 1.3361, 1.3362 and 1.3362, respectively when a wavelength of 546.07nm is used. [Copyright &y& Elsevier]

Purpose: The aim of the present study was to evaluate the disinfection properties of multipurpose contact lens disinfection solutions, based on the International Organization for Standardization (ISO) 14729 guidelines. Methods: Three lots of each of six multi-purpose solutions were tested as follows: Renu MultiPlus, Solo Care Aqua, All-Clean Soft, Contact All-in one Advanced, Hippia, Ginza multi-purpose solution and 0.9% normal saline solution were inoculated with the standard strain of Pseudomonas aeruginosa (ATCC 9027). The surviving bacteria were quantified at specified times. An average logarithm reduction in bacterial numbers at the manufacturer's minimum recommended disinfection time was determined and compared with the criteria for stand-alone disinfection products for each multi-purpose disinfection solution against each bacterial strain. Results: Renu MultiPlus, Solo Care, All-Clean Soft and Contact All-in one Advanced were effective in achieving a four logarithmic units reduction in the bacterial count; however, Renu MultiPlus and Solo Care Aqua resulted in the greatest reduction in bacterial numbers. The other solutions were not effective against Pseudomonas aeruginosa after specified times. Conclusions: Generally, Renu MultiPlus, Solo Care Aqua, All-Clean Soft and Contact All-in one Advanced meet the ISO 14729 guidelines for stand-alone contact lens solutions. [ABSTRACT FROM AUTHOR]

Purpose: To compare comfort-related outcomes when wearing rigid gas permeable (RGP) contact lenses made of two different materials and using two cleaning regimes. Methods: In a double-masked lens material cross-over study, subjects (n = 28 who completed the study) were refitted with new lenses made from (A) Boston XO material in one eye and made from (B) ONSI-56 material in the other eye. The lenses made from materials A and B were worn on the right eye and the left eye following the pattern AB–BA–AB (or vice versa) during the first, second, and third 5 week trial periods respectively. Miraflow cleaner (1st and 2nd period) was replaced by Boston Advance cleaner in the 3rd period. Comfortrelated outcomes were assessed by a numerical rating scale (NRS) after each period. Subjects rated six comfort-related factors: satisfaction, sharpness of vision, end of day comfort, maximum comfortable wearing time, maximum wearing time and foreign body feeling. Additionally we obtained subjects’ preferences for type of lens and lens cleaner during an exit interview. The sessile drop method was used to measure static contact angles. Results: The mean of the contact angle measured for the Boston XO material was 93.3° and for the ONSI-56 material was 75.8°. Mean ‘end of the day comfort’, ‘satisfaction’ and ‘lens feeling’ scores reached statistical significance (anova periods 1, 2 and 3, p’s: 0.005, 0.028, 0.046, n = 23) with marginal differences in favour of those eyes that had worn lenses made of the ONSI-56 material (differences in mean scores on a 1–10 NRS never exceeded 0.7, 0.5 and 0.2 points in periods 1, 2, 3 respectively). At the exit interview 60% of the subjects (n = 17) were not able to express a preference for wearing either of the lenses, while 29% reported some preference for lenses made of the ONSI- 56 material (n = 8) and 11% for wearing lenses made of the Boston XO material (n = 3) within one or more periods. Conclusions: The differences in comfort-related outcomes between contact lenses made from two different materials, with sessile contact angles that differed by 17.5°, were small. Although some observed comfort differences reached statistical significance, none of these differences were sufficiently large to support a clinically significant difference in comfort between the two materials. We recommend that both the sessile drop and the captive bubble contact angles, measured according to current standards, are made available to practitioners. [ABSTRACT FROM AUTHOR]

Purpose: The aim was to document contact lens prescribing trends in Australia between 2000 and 2009. Methods: A survey of contact lens prescribing trends was conducted each year between 2000 and 2009. Australian optometrists were asked to provide information relating to 10 consecutive contact lens fittings between January and March each year. Results: Over the 10-year survey period, 1,462 practitioners returned survey forms representing a total of 13,721 contact lens fittings. The mean age (± SD) of lens wearers was 33.2 ± 13.6 years and 65 per cent were female. Between 2006 and 2009, rigid lens new fittings decreased from 18 to one per cent. Low water content lenses reduced from 11.5 to 3.2 per cent of soft lens fittings between 2000 and 2008. Between 2005 and 2009, toric lenses and multifocal lenses represented 26 and eight per cent, respectively, of all soft lenses fitted. Daily disposable, one- to two-week replacement and monthly replacement lenses accounted for 11.6, 30.0 and 46.5 per cent of all soft lens fittings over the survey period, respectively. The proportion of new soft fittings and refittings prescribed as extended wear has generally declined throughout the past decade. Multi-purpose lens care solutions dominate the market. Rigid lenses and monthly replacement soft lenses are predominantly worn on a full-time basis, whereas daily disposable soft lenses are mainly worn part-time. Conclusions: This survey indicates that technological advances, such as the development of new lens materials, manufacturing methods and lens designs, and the availability of various lens replacement options, have had a significant impact on the contact lens market during the first decade of the 21st Century. [ABSTRACT FROM AUTHOR]

Abstract: Background: The aims of this survey were to appraise contact lens practice and care systems used in Hong Kong between March 2007 and February 2008, and to evaluate the attitude of practitioners towards prescribing different types of contact lenses. Methods: Questionnaires were sent out to 797 optometrists licensed to fit contact lenses in Hong Kong in March 2008. Results: The response rate was 27%. About 20% of contact lens patients (as reported by the respondents) were new wearers. Over 90% of contact lens patients were wearing soft contact lenses. Among soft contact lenses, the use of daily disposable and silicone hydrogel lenses had increased from 27% and 3% in 2002 to 37% and 21% in 2008, respectively. Less than 10% were rigid contact lens wearers. For astigmats fitted with soft lenses, only about 46% were fitted with toric lenses. For presbyopes using contact lenses, the majority (57%) were fitted with single vision lenses with over-spectacles, followed by monovision (29%). The most commonly recommended soft lens disinfecting system was multipurpose solution (74%). Less than 20% of the respondents reported confidence in prescribing orthokeratology lenses. Conclusion: Soft contact lenses continued to dominate the contact lens market in Hong Kong, with silicone hydrogel and daily disposable lenses becoming increasingly popular. The use of toric and bifocal lenses was still not popular among practitioners. Multipurpose solutions were still the care systems of choice by practitioners in Hong Kong. [Copyright &y& Elsevier]

Abstract: Purpose: To determine whether hypo-osmotic saline drops can improve contact lens associated discomfort and dryness by decreasing contact lens osmolality. Methods: Fifteen symptomatic subjects wore Lotrafilcon A lenses bilaterally for 6h on two different days. According to randomisation, hypo-osmotic (280mmol/kg) or hyper-osmotic (380mmol/kg) saline drops were applied four times during each day and ocular symptoms, tear film and contact lens parameters, and contact lens osmolality were assessed. Results: Sixty percent of the subjects preferred the hypo-osmotic saline drops, compared to 33%, who preferred the hyper-osmotic ones. Subjects experienced significantly less dryness and lens awareness with hypo-osmotic saline drops compared to hyper-osmotic ones (p <0.05). Using the hypo-osmotic drops, there was a trend for decreased contact lens osmolality from 379 to 343mmol/kg (p =0.06). There were no differences in lipid layer, non-invasive tear film break-up time, lens surface wettability, lens water content after wear, lens movement on eye or ocular staining and indentation between saline drops (all p >0.05). Interestingly, the difference in contact lens osmolality between drops did not reflect the osmolality difference between the two saline drops. Conclusion: Hypo-osmotic saline drops were preferred by a greater number of subjects and contact lens osmolality tended to be lower with the use of hypo-osmotic saline. Hypo-osmotic drops have the potential to decrease contact lens osmolality which in turn may help improve ocular comfort. This has possible impact on the practitioners’ choice of the lens rewetting drop recommended and the design of future lens rewetting drops. [Copyright &y& Elsevier]

Abstract: The objective of this study was to establish a reasonably simple and reliable method to measure very low concentrations of polyhexamethylene biguanide (PHMB) in multipurpose contact lens solutions (MPSs). By using a weak cation exchange solid phase extraction cartridge to extract the PHMB from MPS, followed by HPLC analysis using an evaporative light scattering detector, low levels (0.1ppm) of PHMB were detected. Application of this method to a series of off-the-shelf MPS with PHMB as the active ingredient demonstrated these solutions contain 1ppm. The contact lens solution with hydrogen peroxide as the active ingredient gave no peak where the PHMB peak eluted. The Polyquad® contact lens solution generated a peak close to the retention time of PHMB. Recovery of PHMB from fortified hydrogen peroxide contact lens solution was good at 0.25ppm and above; 105% with a RSD of 17% or less. The repeatability of the HPLC system ranged from 4 to 11% RSD; the reproducibility of the entire method was less than 17.5% RSD. Storage and stability studies indicated that storage of MPS with PHMB for chemical analysis are not temperature dependent, but are affected by the composition of the container in which the contact lens solution is stored. [Copyright &y& Elsevier]

Abstract: Purpose: To determine the effect of four marketed multipurpose contact lens solutions (MPSs) on corneal epithelial cell viability. Methods: Comparison of the effect of MPS A (Renu MultiPlus, Bausch & Lomb), MPS B (OPTI-FREE Express, Alcon), MPS C (AQuify, CibaVision), and MPS D (OPTI-FREE RepleniSH, Alcon) on cell viability was performed by quantifying cellular ATP content, resazurin reduction, and lactate dehydrogenase (LDH) release in transformed human corneal epithelial cells (HCEpiC) and primary bovine corneal epithelial cells (BCEpiC). Results: Significant reductions in cellular ATP content were observed at 40% solution and above with both MPS B and MPS D, compared to at 100% only for MPS A and MPS C, and similar results were obtained in BCEpiC. Effects on resazurin reduction were also less in HCEpiC exposed to increasing doses of MPS A and MPS C than in cells exposed to MPS B and MPS D. After 15min, HCEpiC viability measured by both resazurin reduction and cellular ATP levels was significantly lower for cells exposed to MPS B, MPS D, and MPS C, while HCEpiC exposed to MPS A were not affected. MPS B and MPS D reduced cell viability more than MPS A and MPS C over a 2-h time course in both HCEpiC and BCEpiC. Conclusions: Both MPS B and MPS D can cause large decreases in the viability of cultured corneal epithelial cells even with just a 2h exposure at multiple doses. Significant reduction in cell viability is evident at brief 15–30min exposures. In contrast, MPS A and MPS C have significantly less effect on the cell viability of corneal epithelial cells at multiple doses, after these short exposure times. [Copyright &y& Elsevier]

Contact lens hygiene has long been recognised as key to the prevention of contact-lens associated infection and inflammation. Microbial keratitis (MK) is the only serious and potentially sight-threatening contact lens adverse event. International studies including recent research in Asia Pacific show that MK is rare but, as the consequences can be severe, it is important to minimise the risk factors. Studies continue to show that one of the key risk factors is lens and lens case hygiene. Therefore, it is also useful to review the behaviour of our patients, to see how closely they follow the recommended hygiene practices. Recent studies in various regions have shown that patients’ lens care habits do not meet a required standard. Patients can become complacent and thus non-compliant with lens care instructions. Furthermore, they do not understand the high risk of some behaviour and they are not hearing the practitioner when instructions and reminders are given. Further education is important to improve patient compliance and safety. The Asia Pacific Contact Lens Care Summit held in Singapore urged the industry and practitioners to restore the emphasis of proper lens care, including the ‘rub and rinse’ technique, and developed a new set of guidelines to help eye-care professionals educate their patients on the importance of proper contact lens care to avoid eye infections. The summit also presented the latest research on how to avoid corneal staining, another important element of contact lens care. This review provides a summary of the summit presentations and the science behind these guidelines. [ABSTRACT FROM AUTHOR]

Purpose:To determine whether multipurpose solutions, widely used for contact lens disinfections, could be at the origin of ocular pathologies (contact lens intolerance and ocular infections).Methods:An observational cohort study (questionnaire analysis) was carried out to estimate the number of contact lens wearers, type of infection, and type of lens care regimen used by patients. Besides, multipurpose solutions cytotoxicity (necrosis and apoptosis) was evaluated on a conjunctival cell line using cytofluorometry.Results:In the general population, 59% of contact lens wearers use multipurpose solutions whereas 35% use oxidative products. Of the questioned contact lens wearers with ocular infections, 80% used multipurpose solutions. Multipurpose solutions are therefore not efficient enough against microorganisms, and cannot be considered as disinfectant solutions but only as preservatives. However, preservatives are known to be toxic to ocular surface, so apoptosis induced by multipurpose solutions could lead to ocular surface diseases. Our cytofluorometry study allowed us to demonstrate that contact lens multipurpose solutions containing preservatives are cytotoxic through caspase 3 induction, chromatin condensation and P2X7 cell-death receptor activation, in contrast with unpreserved sterile saline solutions that were found inert.Conclusions:Multipurpose solutions seem to be preservative but not disinfecting solutions. They are not adapted to the final rinse of contact lenses because of apoptosis induction. It could explain part of lens intolerance.Eye (2009) 23, 470–476; doi:10.1038/eye.2008.131; published online 16 May 2008 [ABSTRACT FROM AUTHOR]

Purpose: To compare effectiveness of cleaning with and without rubbing of soft contact lenses. Methods: Three-hundred new biweekly disposable hydrogel lenses (Ocufilcon D, FDA Group IV; 55% water content) were artificially deposited with serum albumin, hand cream (semi-transparent deposits) and mascara (black deposits). The treated lenses were randomly divided into three groups, each group cleaned by one of three methods of cleaning — Rubbing (R), No-Rub following the manufacturer’s instruction on duration of rinsing (NR1) and No-Rub with a shorter duration of rinsing (NR2). Four commercially-available multipurpose solutions (MPS) and a saline were used. The cleaning effectiveness was determined by the amount of deposits remaining on the contact lenses after cleaning, assessed with the aid of a slit-lamp. The level of deposits remaining (in terms of coverage of lens surface) were determined using a five-point scale [0 (no observable deposits) – 4 (>80% deposits remained)] for semi-transparent deposits (protein and hand cream) and black deposits (mascara). The investigators were masked as to the solutions used (except for one MPS which has a different rinsing time than the other MPS), and the investigator who assessed the deposits left on the lenses did not know which solution or cleaning method was used to clean each lens. Results: Lenses cleaned by the R method were significantly cleaner than those cleaned by methods NR1 and NR2. No significant difference was found between lenses cleaned by NR1 and NR2 methods. The median grade of deposits for lenses cleaned by R method was 0.5 for both semi-transparent and black deposits. For lenses cleaned by NR1 and NR2 methods, the median grade of deposits left on lens surfaces was 4.0 for both types of deposits. Different solutions used did not affect the level of deposits left on lens surfaces for all three cleaning methods. Conclusions: Not rubbing the soft lens when cleaning is ineffective in removing loosely-bound deposits. A longer rinse, as recommended by the manufacturers, does not remove significantly more deposits than a shorter rinse with the MPS. This work supports the view that contact lens wearers should be encouraged to rub their lenses when cleaning. [ABSTRACT FROM AUTHOR]

Purpose: To document contact lens prescribing trends in the United Kingdom over the past decade (between 1996 and 2005). Methods: An annual survey of contact lens prescribing trends was conducted each year by asking a random selection of optometrists and dispensing opticians to provide information relating to 10 consecutive contact lens fits between January and March. Results: Over the 10-year survey period, 1251 practitioners returned survey forms representing a total of 12,050 contact lens fits. The mean (+/-standard deviation) age of lens wearers was 33+/-13 years of which 64% were female. Over the survey period, rigid lens new fits decreased from 22% to 4%. Low water content lenses reduced from 20% to 2% of new soft lens fits. Soft toric lenses gradually increased to the point where they accounted for the expected proportion of patients with astigmatism>or=1.00DC (i.e. >20% of soft lens fits). Monthly and daily disposable lenses accounted for >90% of all soft lens fits between 2003 and 2005. The proportion of new soft fits and refits prescribed as extended wear has gradually increased, stabilizing at about 5% of new fits and 12% of refits. Multi-purpose lens care solutions increased from 60% of all care systems in 1997 to 91% in 2005. Rigid lenses and monthly replacement soft lenses are predominantly worn on a full time basis, whereas daily disposable soft lenses are mainly worn part time. Conclusions: This survey indicates that technological advancements such as the development of new lens materials, manufacturing methods and lens designs have had a significant impact on the contact lens market over a relatively short period of time. [ABSTRACT FROM AUTHOR]

Abstract: Aim: The disinfection efficacy of contact lens multipurpose solutions (MPSs) against Acanthamoeba polyphaga (Ros) and Acanthamoeba castellanii (ATCC30868) cysts and trophozoites was determined by both biocidal and manufacturer-recommended no-rub/rinse regimen testing. Methods: A biocidal assay using four MPSs (ReNu® with MoistureLoc®, Opti-free Express, Solo-care Plus, and Complete MoisturePlus) was conducted with or without the presence of organic soil. A second test procedure compared the ability of five MPSs (ReNu with MoistureLoc MPS, ReNu MultiPlus, Opti-free Express, Solo-care Aqua, and Complete MoisturePlus) to remove and kill Acanthamoeba species cysts and trophozoites from SofLens 38 and Surevue conventional hydrogel lenses, and Focus Night & Day silicone hydrogel lenses using the manufacturer-recommended regimen. Results: In the biocidal assay, only ReNu with MoistureLoc successfully killed both trophozoites and cysts (>3 log) within the manufacturer-recommended soak time. A >3 log decrease in trophozoites, but not cysts, was reported for Opti-free Express; however, Solo-care Plus and Complete MoisturePlus did not reduce the number of cysts or trophozoites by >3 log during the manufacturer-recommended soak time. In the no-rub/rinse regimen tests, only ReNu with MoistureLoc removed an inoculum of 2×105 trophozoites or cysts from SofLens 38 and Surevue hydrogel lenses, as well as Focus Night & Day silicone hydrogel lenses. Less than 10 viable organisms were recovered from the lenses after the 10s rinse and 4h soak. Opti-free Express, Solo-care Aqua, and ReNu MultiPlus were effective at removing trophozoites and cysts from SofLens 38 and Surevue conventional hydrogel lenses, but not from Focus Night & Day silicone hydrogel lenses. In excess of 10 viable organisms were recovered from all lenses after the manufacturer-recommended regimen using Complete MoisturePlus. Conclusions: These data suggest that some MPSs, when used as recommended by the manufacturer, are more effective at killing representative strains of Acanthamoeba than others. [Copyright &y& Elsevier]

Sigalas E, Regan JD, Kramer PR, Witherspoon DE, Opperman LA. Survival of human periodontal ligament cells in media proposed for transport of avulsed teeth. Dent Traumatol 2004; 20: 21–28. © Blackwell Munksgaard, 2004. Many solutions have been examined as possible storage media for avulsed teeth. In this report, human periodontal ligament (PDL) cells were exposed for 1 h to culture medium, milk, Hanks Balanced Salt Solution (HBSS), Soft Wear, Opti Free, and Solo Care contact lens solutions, Gatorade®, and tap water, at room temperature and on ice. The number of viable cells was counted using the trypan blue exclusion technique, immediately after exposure (0 h) and at 24 and 48 h, to test the proliferative capacity of the cells after treatment. The results indicated that a significantly higher number of cells survived and proliferated when the exposures were performed at 0°C. Water had a detrimental effect on the cells, whereas culture medium and HBSS preserved significantly more viable cells than the other experimental solutions. Within the parameters of this study, it appears that HBSS is the optimal storage medium for avulsed teeth. Low-fat milk could serve as an alternative if ice is available. Contact lens solutions or Gatorade® on ice could serve as short-term (1 h) storage media if the other solutions are not readily available. [ABSTRACT FROM AUTHOR]

Positive patch test reactions 0.1% pet. (40/690 subjects: 5.8%) were more common in younger age groups, in the allergic contact dermatitis group and in subjects who had used contact lens solutions. In the 40 thimerosal-positive patients, the minimum eliciting quantity of preservative was evaluated using different test concentrations: 0.05% and 0.01% pet. (patch testing) and 1:10.000 in saline (intradermal testing). Cross-reactions between thimerosal and other mercury compounds and sensitivity to thiosalicylic acid were also examined. The results of the investigation demonstrate that many of the reactions to 0.1% thimerosal are probably irritant, because only half the subjects studied had positive patch tests when allergen concentrations 5 to 10 × lower than that conventionally used for patch testing, were utilized. In these subjects, the average strength of patch test reactions was higher, intradermal testing was more often positive and cross-reactions between mercurials more frequent. These data indicate that the optimal eliciting patch test concentration for studying thimerosal sensitivity is 0.05% pet. [ABSTRACT FROM AUTHOR]

Abstract: Propylene glycol used as an ophthalmic demulcent in certain contact-lens care systems has been included recently among factors responsible for increasing Acanthamoeba keratitis. In this study, we provide evidence that propylene glycol as well as examined contact-lens solutions containing it induce rapid differentiation of acanthamoebae into pseudocysts. The partial resistance of the pseudocysts and their reversibility to viable trophozoites even after 24-h exposure to the contact-lens solutions indicate a potential risk of infection to contact-lens users. [ABSTRACT FROM AUTHOR]

Contact lens care is an essential part of our practice. In recent years, we have been reminded of the devastating issues that present when patients lack compliance when caring for their contact lenses. Without proper compliance, adequate contact lens disinfection is not attained, resulting in compromised health and safety of patients. Knowledge of current contact lens solutions is critical for us to properly care for our patients. This article reviews soft contact lens solutions — including both multipurpose solutions and hydrogen peroxide solutions — that are currently available. [ABSTRACT FROM AUTHOR]

Abstract: 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. [Copyright &y& Elsevier]