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Contact lens hygiene compliance and lens case contamination: A review

      Abstract

      A contaminated contact lens case can act as a reservoir for microorganisms that could potentially compromise contact lens wear and lead to sight threatening adverse events. The rate, level and profile of microbial contamination in lens cases, compliance and other risk factors associated with lens case contamination, and the challenges currently faced in this field are discussed. The rate of lens case contamination is commonly over 50%. Coagulase-negative Staphylococcus, Bacillus spp., Pseudomonas aeruginosa and Serratia marcescens are frequently recovered from lens cases. In addition, we provide suggestions regarding how to clean contact lens cases and improve lens wearers’ compliance as well as future lens case design for reducing lens case contamination. This review highlights the challenges in reducing the level of microbial contamination which require an industry wide approach.

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      References

        • Dart J.K.G.
        • Stapleton F.
        • Minassian D.
        Contact lenses and other risk factors in microbial keratitis.
        Lancet. 1991; 338: 650-654
        • Van der Meulen I.J.
        • Van Rooij J.
        • Nieuwendaal C.P.
        • Van Cleijnenbreugel H.
        • Geerards A.J.
        • Remeijer L.
        Age-related risk factors, culture outcomes, and prognosis in patients admitted with infectious keratitis to two Dutch tertiary referral centers.
        Cornea. 2008; 27: 539-544
        • Fong C.F.
        • Tseng C.H.
        • Hu F.R.
        • Wang I.J.
        • Chen W.L.
        • Hou Y.C.
        Clinical characteristics of microbial keratitis in a university hospital in Taiwan.
        Am J Ophthalmol. 2004; 137: 329-336
        • Erie J.C.
        • Nevitt M.P.
        • Hodge D.O.
        • Ballard D.
        Incidence of ulcerative keratitis in a defined population from 1950 through 1988.
        Arch Ophthalmol. 1993; 111: 1665-1671
        • Toshida H.
        • Kogure N.
        • Inoue N.
        • Murakami A.
        Trends in microbial keratitis in Japan.
        Eye Contact Lens. 2007; 33: 70-73
        • Cheng K.
        • Leung D.
        • Hoekman H.
        • Haudijn Beekhuis W.
        • Mulder P.
        • Geerards A.
        • et al.
        Incidence of contact-lens-associated microbial keratitis and its related morbidity.
        Lancet. 1999; 354: 181-184
        • Liesegang T.J.
        Contact lens-related microbial keratitis: part I: epidemiology.
        Cornea. 1997; 16: 125-131
        • Stapleton F.
        • Naduvilath T.
        • Keay L.J.
        • Radford C.F.
        • Dart J.K.
        • Edwards K.
        • et al.
        Risk factors for microbial keratitis in daily disposable contact lens wear.
        Invest Ophthalmol Vis Sci. 2010; 51: 1305
        • Stapleton F.
        • Keay L.
        • Edwards K.
        • Naduvilath T.
        • Dart J.K.
        • Brian G.
        • et al.
        The incidence of contact lens-related microbial keratitis in Australia.
        Ophthalmology. 2008; 115: 1655-1662
        • Dart J.K.
        • Radford C.F.
        • Minassian D.
        • Verma S.
        • Stapleton F.
        Risk factors for microbial keratitis with contemporary contact lenses: a case–control study.
        Ophthalmology. 2008; 115 (54 e1-3): 1647-1654
        • Keay L.
        • Edwards K.
        • Naduvilath T.
        • Forde K.
        • Stapleton F.
        Factors affecting the morbidity of contact lens-related microbial keratitis: a population study.
        Invest Ophthalmol Vis Sci. 2006; 47: 4302-4308
        • Stapleton F.
        • Dart J.K.
        • Minassian D.
        Risk factors with contact lens related suppurative keratitis.
        CLAO J. 1993; 19: 204-210
        • Edwards K.
        • Keay L.
        • Naduvilath T.
        • Snibson G.
        • Taylor H.
        • Stapleton F.
        Characteristics of and risk factors for contact lens-related microbial keratitis in a tertiary referral hospital.
        Eye. 2009; 23: 153-160
        • Lam D.S.C.
        • Houang E.
        • Fan D.S.P.
        • Lyon D.
        • Seal D.
        • Wong E.
        Incidence and risk factors for microbial keratitis in Hong Kong: comparison with Europe and North America.
        Eye. 2002; 16: 608-618
        • Radford C.F.
        • Minassian D.C.
        • Dart J.K.
        Disposable contact lens use as a risk factor for microbial keratitis.
        Br J Ophthalmol. 1998; 82: 1272-1275
        • Morgan P.B.
        • Efron N.
        • Brennan N.A.
        • Hill E.A.
        • Raynor M.K.
        • Tullo A.B.
        Risk factors for the development of corneal infiltrative events associated with contact lens wear.
        Invest Ophthalmol Vis Sci. 2005; 46: 3136-3143
        • Schein O.D.
        • Glynn R.J.
        • Poggio E.C.
        • Seddon J.M.
        • Kenyon K.R.
        The relative risk of ulcerative keratitis among users of daily-wear and extended-wear soft contact lenses.
        N Engl J Med. 1989; 321: 773-778
        • Mayo M.S.
        • Schlitzer R.L.
        • Ward M.A.
        • Wilson L.A.
        • Ahearn D.G.
        Association of Pseudomonas and Serratia corneal ulcers with use of contaminated solutions.
        J Clin Microbiol. 1987; 25: 1398-1400
        • Radford C.F.
        • Minassian D.C.
        • Dart J.K.
        Acanthamoeba keratitis in England and Wales: incidence, outcome, and risk factors.
        Br J Ophthalmol. 2002; 86: 536-542
        • Bates A.K.
        • Morris R.J.
        • Stapleton F.
        • Minassian D.
        • Dart J.K.G.
        ‘Sterile’ corneal infiltrates in contact lens wearers.
        Eye. 1989; 3: 803-810
        • Stapleton F.
        • Dart J.K.
        • Seal D.V.
        • Matheson M.
        Epidemiology of Pseudomonas aeruginosa keratitis in contact lens wearers.
        Epidemiol Infect. 1995; 114: 395-402
        • Kilvington S.
        • Gray T.
        • Dart J.
        • Morlet N.
        • Beeching J.R.
        • Frazer D.G.
        • et al.
        Acanthamoeba keratitis: the role of domestic tap water contamination in the United Kingdom.
        Invest Ophthalmol Vis Sci. 2004; 45: 165-169
        • Mayo M.S.
        • Cook W.L.
        • Schlitzer R.L.
        • Ward M.A.
        • Wilson L.A.
        • Ahearn D.G.
        Antibiograms, serotypes, and plasmid profiles of Pseudomonas aeruginosa associated with corneal ulcers and contact lens wear.
        J Clin Microbiol. 1986; 24: 372-376
        • Wiley L.
        • Bridge D.R.
        • Wiley L.A.
        • Odom J.V.
        • Elliott T.
        • Olson J.C.
        Bacterial biofilm diversity in contact lens-related disease: emerging role of Achromobacter, Stenotrophomonas, and Delftia.
        Invest Ophthalmol Vis Sci. 2012; 53: 3896-3905
        • Simmons P.A.
        • Edrington T.B.
        • Hsieh L.
        • Wang L.
        Bacterial contamination rate of soft contact lens cases.
        Int Contact Lens Clin. 1991; 18: 188-191
        • Wu Y.T.
        • Zhu H.
        • Harmis N.Y.
        • Iskandar S.Y.
        • Willcox M.
        • Stapleton F.
        Profile and frequency of microbial contamination of contact lens cases.
        Optom Vis Sci. 2010; 87: E152-E158
        • Gray T.B.
        • Cursons R.T.
        • Sherwan J.F.
        • Rose P.R.
        Acanthamoeba, bacterial, and fungal contamination of contact lens storage cases.
        Br J Ophthalmol. 1995; 79: 601-605
        • Wilson L.A.
        • Sawant A.D.
        • Simmons R.B.
        • Ahearn D.G.
        Microbial contamination of contact lens storage cases and solutions.
        Am J Ophthalmol. 1990; 110: 193-198
        • Szczotka-Flynn L.
        • Pearlman E.
        • Ghannoum M.
        Microbial contamination of contact lenses, lens care solutions, and their accessories: a literature review.
        Eye Contact Lens: Sci Clin Pract. 2010; 36: 116-129
        • Callender M.G.
        • Tse L.S.Y.
        • Charles A.M.
        • Lutzi D.
        Bacterial flora of the eye and contact lens cases during hydrogel lens wear.
        Am J Optom Physiol Opt. 1986; 63: 177-180
        • Donzis P.B.
        • Mondino B.J.
        • Weissman B.A.
        • Bruckner D.A.
        Microbial contamination of contact lens care systems.
        Am J Ophthalmol. 1987; 104: 325-333
        • Larkin D.F.
        • Kilvington S.
        • Easty D.L.
        Contamination of contact lens storage cases by Acanthamoeba and bacteria.
        Br J Ophthalmol. 1990; 74: 133-135
        • Devonshire P.
        • Munro F.A.
        • Abernethy C.
        • Clark B.J.
        Microbial contamination of contact lens cases in the west of Scotland.
        Br J Ophthalmol. 1993; 77: 41-45
        • Midelfart J.
        • Midelfart A.
        • Bevanger L.
        Microbial contamination of contact lens cases among medical students.
        CLAO J. 1996; 22: 21-24
        • Velasco J.
        • Bermudez J.
        Comparative study of the microbial flora on contact lenses, in lens cases, and in maintenance liquids.
        Int Contact Lens Clin. 1996; 23: 55-58
        • McLaughlin-Borlace L.
        • Stapleton F.
        • Matheson M.
        • Dart J.K.G.
        Bacterial biofilm on contact lenses and lens storage cases in wearers with microbial keratitis.
        J Appl Microbiol. 1998; 84: 827-838
        • Seal D.
        • Dalton A.
        • Doris D.
        Disinfection of contact lenses without tap water rinsing: is it effective?.
        Eye. 1999; 13: 226-230
        • Boost M.V.
        • Cho P.
        Microbial flora of tears of orthokeratology patients, and microbial contamination of contact lenses and contact lens accessories.
        Optom Vis Sci. 2005; 82: 451-458
        • Yung M.S.
        • Boost M.
        • Cho P.
        • Yap M.
        Microbial contamination of contact lenses and lens care accessories of soft contact lens wearers (university students) in Hong Kong.
        Ophthalmic Physiol Opt. 2007; 27: 11-21
        • Pens C.J.
        • da Costa M.
        • Fadanelli C.
        • Caumo K.
        • Rott M.
        Acanthamoeba spp. and bacterial contamination in contact lens storage cases and the relationship to user profiles.
        Parasitol Res. 2008; 103: 1241-1245
        • Willcox M.D.
        • Carnt N.
        • Diec J.
        • Naduvilath T.
        • Evans V.
        • Stapleton F.
        • et al.
        Contact lens case contamination during daily wear of silicone hydrogels.
        Optom Vis Sci. 2010; 87: 456-464
        • Kuzman T.
        • Kutija M.B.
        • Juri J.
        • Jandroković S.
        • Škegro I.
        • Olujić S.M.
        • et al.
        Lens wearers non-compliance – is there an association with lens case contamination?.
        Contact Lens Anterior Eye. 2014; 37: 99-105
        • Wu Y.T.
        • Willcox M.D.P.
        • Stapleton F.
        The effect of contact lens hygiene behavior on lens case contamination.
        Optom Vis Sci. 2015; 92 (10.1097/OPX.0000000000000477): 167-174
        • Willcox M.D.
        • Harmis N.Y.
        • Holden B.A.
        Bacterial populations on high-Dk silicone hydrogel contact lenses: effect of length of wear in asymptomatic patients.
        Clin Exp Optom. 2002; 85: 172-175
        • Iskeleli G.
        • Bahar H.
        • Unal M.
        • Artunay O.
        • Akova N.
        • Torun M.M.
        Microbiologic evaluation of frequent-replacement soft contact lenses.
        CLAO J. 2002; 28: 192-195
        • Willcox M.D.
        Solutions for care of silicone hydrogel lenses.
        Eye Contact Lens. 2013; 39: 24-28
        • Wiley L.
        • McAllister M.
        • Wiley L.A.
        • Elliott T.
        • Bridge D.
        • Odom J.V.
        • et al.
        Biofilm bacterial diversity: association with disease severity in contact lens related keratitis association for research in vision and ophthalmology meeting.
        2011 (6508/D972)
        • Holden B.A.
        • La Hood D.
        • Grant T.
        • Newton-Howes J.
        • Baleriola-Lucas C.
        • Willcox M.D.
        • et al.
        Gram-negative bacteria can induce contact lens related acute red eye (CLARE) responses.
        CLAO J. 1996; 22: 47-52
        • Sankaridurg P.R.
        • Sharma S.
        • Willcox M.D.
        Colonization of hydrogel lenses with Streptococcus pneumoniae: risk of development of corneal infiltrates.
        Cornea. 1999; 18: 289-295
        • Sankaridurg P.R.
        • Holden B.A.
        • Jalbert I.
        Adverse effects and infections: which ones and how many?.
        in: Sweeney D.F. Silicone hydrogels: continuous-wear contact lenses. 2nd ed. Butterworth Heinemann, Oxford2004: 217-274
        • Ibrahim Y.W.
        • Boase D.L.
        • Cree I.A.
        Epidemiological characteristics, predisposing factors and microbiological profiles of infectious corneal ulcers: the Portsmouth corneal ulcer study.
        Br J Ophthalmol. 2009; 93: 1319-1324
        • Dart J.K.G.
        Predisposing factors in microbial keratitis: the significance of contact lens wear.
        Br J Ophthalmol. 1988; 72: 926-930
        • Lyczak J.B.
        • Cannon C.L.
        • Pier G.B.
        Establishment of Pseudomonas aeruginosa infection: lessons from a verstaile opportunist.
        Microb Infect. 2000; 2: 1051-1060
        • Lakkis C.
        • Fleiszig S.M.
        Resistance of Pseudomonas aeruginosa isolates to hydrogel contact lens disinfection correlates with cytotoxic activity.
        J Clin Microbiol. 2001; 39: 1477-1486
        • Gopinathan U.
        • Stapleton F.
        • Sharma S.
        • Willcox M.D.
        • Sweeney D.F.
        • Rao G.N.
        • et al.
        Microbial contamination of hydrogel contact lenses.
        J Appl Microbiol. 1997; 82: 653-658
        • Fleiszig S.M.
        • Efron N.
        Microbial flora in eyes of current and former contact lens wearers.
        J Clin Microbiol. 1992; 30: 1156-1161
        • Hart D.E.
        • Reindel W.
        • Proskin H.M.
        • Mowrey-McKee M.F.
        Microbial contamination of hydrophilic contact lenses: quantitation and identification of microorganisms associated with contact lenses while on the eye.
        Optom Vis Sci. 1993; 70: 185-191
        • Leitch E.C.
        • Harmis N.Y.
        • Corrigan K.M.
        • Wilcox M.D.
        Identification and enumeration of staphylococci from the eye during soft contact lens wear.
        Optom Vis Sci. 1998; 75: 781-782
        • Wu P.
        • Thakur A.
        • Stapleton F.
        • Willcox M.
        Staphylococcus aureus causes acute inflammatory episodes in the cornea during contact lens wear.
        Clin Exp Ophthalmol. 2000; 28: 194-196
        • Seal D.V.
        • Barrett S.P.
        • McGill J.L.
        Aetiology and treatment of acute bacterial infection of the external eye.
        Br J Ophthalmol. 1982; 66: 357-360
        • Ormerod D.L.
        • Smith R.E.
        Contact lens-associated microbial keratitis.
        Arch Ophthalmol. 1986; 104: 79-83
        • Jalbert I.
        • Willcox M.D.
        • Sweeney D.F.
        Isolation of Staphylococcus aureus from a contact lens at the time of a contact lens-induced peripheral ulcer: case report.
        Cornea. 2000; 19: 116-120
        • Lakkis C.
        • Anastasopoulos F.
        • Terry C.
        • Borazjani R.
        Time course of the development of contact lens case and contact lens contamination.
        Association for Research in Vision and Ophthalmology Fort Lauderdale, USA2009 (an abstract)
        • Qu W.
        • Hooymans J.M.
        • de Vries J.
        • van der Mei H.C.
        • Busscher H.J.
        Force analysis of bacterial transmission from contact lens cases to corneas, with the contact lens as the intermediary.
        Invest Ophthalmol Vis Sci. 2011; 52: 2565-2570
        • Szczotka-Flynn L.B.
        • Imamura Y.
        • Chandra J.
        • Yu C.
        • Mukherjee P.K.
        • Pearlman E.
        • et al.
        Increased resistance of contact lens-related bacterial biofilms to antimicrobial activity of soft contact lens care solutions.
        Cornea. 2009; 28: 918-926
        • Wu Y.T.
        • Teng Y.J.
        • Nicholas M.
        • Harmis N.
        • Zhu H.
        • Willcox M.D.
        • et al.
        Impact of lens case hygiene guidelines on contact lens case contamination.
        Optom Vis Sci. 2011; 88: E1180-E1187
        • Rosenthal R.A.
        • Stein J.M.
        • McAnally C.L.
        • Schlech B.A.
        A comparative study of the microbiologic effectiveness of chemical disinfectants and peroxide neutraliser systems.
        CLAO J. 1995; 21: 99-110
        • Dart J.
        Contamination of contact lens storage cases.
        Br J Ophthalmol. 1990; 74: 129-132
        • Dart J.
        The inside story: why contact lens cases become contaminated.
        Contact Lens Anterior Eye. 1997; 20: 113-118
        • Costerton J.W.
        • Stewart P.S.
        • Greenberg E.P.
        Bacterial biofilms: a common cause of persistent infections.
        Science. 1999; 284: 1318-1322
        • Drenkard E.
        Antimicrobial resistance of Pseudomonas aeruginosa biofilms.
        Microbes Infect. 2003; 5: 1213-1219
        • Donlan R.M.
        • Costerton J.W.
        • Biofilms:
        survival mechanisms of clinically relevant microorganisms.
        Clin Microbiol Rev. 2002; 15: 167-193
        • McKenney C.D.
        • Ajello M.
        Comparative case contamination: three disinfection systems.
        Int Contact Lens Clin. 1991; 18: 14-19
        • Farber B.F.
        • Hsieh H.C.
        • Donnenfeld E.D.
        • Perry H.D.
        • Epstein A.
        • Wolff A.
        A novel antibiofilm technology for contact lens solutions.
        Ophthalmology. 1995; 102: 831-836
        • Radford C.F.
        • Woodward E.G.
        • Stapleton F.
        Contact lens hygiene compliance in a University population.
        J Br Contact Lens Assoc. 1993; 16: 105-111
        • Sokol J.L.
        • Mier M.G.
        • Bloom S.
        • Asbell P.A.
        A study of patient compliance in a contact lens-wearing population.
        CLAO J. 1990; 16: 209-213
        • ISO
        Ophthalmic optics-contact lens care products.
        Microbiological requirements and test methods for products and regimens for hygienic management of contact lenses. International Organization for Standardization, Geneva, Switzerland2001
      1. Guidance for industry premarket notification [510(k)].
        Guidance document for contact lens care products: Food and Drug Administration. 1997
        • Wilson L.A.
        • Sawant A.D.
        • Ahearn D.G.
        Comparative efficacies of soft contact lens disinfectant solutions against microbial films in lens cases.
        Arch Ophthalmol. 1991; 109: 1155-1157
        • Kilvington S.
        • Huang L.
        • Kao E.
        • Powell C.H.
        Development of a new contact lens multipurpose solution: comparative analysis of microbiological, biological and clinical performance.
        J Optom. 2010; 3: 134-142
        • Stapleton F.
        • Choy M.
        • Zhu H.
        Susceptibility of ocular isolates of P. aeruginosa to contact lens multipurpose solutions.
        Association for Research in Vision and Ophthalmology, Fort Lauderdale, FL, USA2011 (Poster num:6507/D971)
        • Morgan P.B.
        • Efron N.
        A decade of contact lens prescribing trends in the United Kingdom (1996–2005).
        Contact Lens Anterior Eye. 2006; 29: 59-68
        • Woods C.A.
        • Morgan P.B.
        Use of silicone hydrogel contact lenses by Australian optometrists.
        Clin Exp Optom. 2004; 87: 19-23
        • Hughes R.
        • Kilvington S.
        Comparison of hydrogen peroxide contact lens disinfection systems and solutions against Acanthamoeba polyphaga.
        Antimicrob Agents Chemother. 2001; 45: 2038-2043
        • Vermeltfoort P.B.
        • Hooymans J.M.
        • Busscher H.J.
        • van der Mei H.C.
        Bacterial transmission from lens storage cases to contact lenses – effects of lens care solutions and silver impregnation of cases.
        J Biomed Mater Res B Appl Biomater. 2008; 87: 237-243
        • Yung A.M.
        • Boost M.V.
        • Cho P.
        • Yap M.
        The effect of a compliance enhancement strategy (self-review) on the level of lens care compliance and contamination of contact lenses and lens care accessories.
        Clin Exp Optom. 2007; 90: 190-202
        • Hickson-Curran S.
        • Chalmers R.L.
        • Riley C.
        Patient attitudes and behavior regarding hygiene and replacement of soft contact lenses and storage cases.
        Contact Lens Anterior Eye. 2011; 34: 207-215
        • Lakkis C.
        • Anastasopoulos F.
        • Terry C.
        • Borazjani R.
        Time course of the development of contact lens case and contact lens contamination.
        ARVO Meeting Abstracts. 2009; 50: 6352
        • Stapleton F.
        • Edwards K.
        • Keay L.
        • Naduvilath T.
        • Dart J.K.
        • Brian G.
        • et al.
        Risk factors for severe microbial keratitis in daily wear contact lens users.
        Invest Ophthalmol Vis Sci. 2008; 49: 4853
        • Stapleton F.
        • Edwards K.
        • Keay L.
        • Naduvilath T.
        • Dart J.K.G.
        • Brian G.
        • Holden B.
        Risk factors for moderate and severe microbial keratitis in daily wear contact lens users.
        Ophthalmology. 2012; 119: 1516-1521
        • Wu Y.
        • Carnt N.
        • Stapleton F.
        Contact lens user profile, attitudes and level of compliance to lens care.
        Contact Lens Anterior Eye. 2010; 33: 183-188
        • Wu Y.
        • Carnt N.
        • Willcox M.
        • Stapleton F.
        Contact lens and lens storage case cleaning instructions: whose advice should we follow?.
        Eye Contact Lens. 2010; 36: 68-72
      2. Food and Drug Administration USA. Focusing on contact lens safety. Available at: http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm048893.htm [accessed 27.07.09]

        • Wu Y.T.
        • Zhu H.
        • Willcox M.
        • Stapleton F.
        The effectiveness of various cleaning regimens and current guidelines in contact lens case biofilm removal.
        Invest Ophthalmol Vis Sci. 2011; 52: 5287-5292
        • Penley C.A.
        • Llabres C.
        • Wilson L.A.
        • Ahearn D.G.
        Efficacy of hydrogen peroxide disinfection systems for soft contact lenses contaminated with fungi.
        CLAO J. 1985; 11: 65-68
        • Kanpolat A.
        • Kalayci D.
        • Arman D.
        • Duruk K.
        Contamination in contact lens care systems.
        Contact Lens Assoc Ophthalmol J. 1992; 18: 104-107
        • Dannelly H.K.
        • Waworuntu R.V.
        Effectiveness of contact lens disinfectants after lens storage.
        Eye Contact Lens. 2004; 30: 163-165
        • Pinzauti S.
        • La Porta E.
        • Papeschi G.
        Chlorhexidine loss from simulated contact lens solutions stored in glass and plastic packages.
        J Pharm Biomed Anal. 1984; 2: 101-105
        • Zhao G.
        • Stevens Jr., S.E.
        Multiple parameters for the comprehensive evaluation of the susceptibility of Escherichia coli to the silver ion.
        Biometals. 1998; 11: 27-32
        • Amos C.F.
        • George M.D.
        Clinical and laboratory testing of a silver-impregnated lens case.
        Contact Lens Anterior Eye. 2006; 29: 247-255
        • Hall B.
        • Jones L.
        Contact lens cases: the missing link in contact lens safety?.
        Eye Contact Lens. 2010; 36: 101-105
        • Dantam J.
        • Zhu H.
        • Stapleton F.
        Biocidal efficacy of silver-impregnated contact lens storage cases in vitro.
        Invest Ophthalmol Vis Sci. 2011; 52: 51-57
        • Dantam J.
        • Zhu H.
        • Willcox M.
        • Ozkan J.
        • Naduvilath T.
        • Thomas V.
        • et al.
        In vivo assessment of antimicrobial efficacy of silver-impregnated contact lens storage cases.
        Invest Ophthalmol Vis Sci. 2012; 53: 1641-1648
        • Reid T.
        • Tran P.
        • Jarvis C.
        • Thomas J.
        • Tran K.
        • Mosley T.
        • et al.
        Antimicrobial properties of selenium covaletly incorporated into the polymer of contact lens case material.
        Assoc Res Vis Ophthalmol. 2012; (Program No:6801, D902)
        • Dutta D.
        • Willcox M.D.
        Antimicrobial contact lenses and lens cases: a review.
        Eye Contact Lens. 2014; 40: 312-324
        • Chun M.W.
        • Weissman B.A.
        Compliance in contact lens care.
        Am J Optom Physiol Opt. 1987; 64: 274-276
        • Claydon B.E.
        • Efron N.
        Non-compliance in contact lens wear.
        Ophthalmic Physiol Opt. 1994; 14: 356-364
        • Collins M.J.
        • Carney L.G.
        Patient compliance and its influence on contact lens wearing problems.
        Am J Optom Physiol Opt. 1986; 63: 952-956
        • Morgan P.B.
        • Efron N.
        • Toshida H.
        • Nichols J.J.
        An international analysis of contact lens compliance.
        Contact Lens Anterior Eye. 2011; 34: 223-228
        • Richdale K.
        • Sinnott L.T.
        • Skadahl E.
        • Nichols J.J.
        Frequency of and factors associated with contact lens dissatisfaction and discontinuation.
        Cornea. 2007; 26: 168-174
        • Carnt N.
        • Keay L.
        • Willcox M.
        • Evans V.
        • Stapleton F.
        Higher risk taking propensity of contact lens wearers is associated with less compliance.
        Contact Lens Anterior Eye. 2011; 34: 202-206
        • Yeung K.K.
        • Forister J.F.
        • Forister E.F.
        • Chung M.Y.
        • Han S.
        • Weissman B.A.
        Compliance with soft contact lens replacement schedules and associated contact lens-related ocular complications: the UCLA Contact Lens Study.
        Optometry. 2010; 81: 598-607
        • Mowrey-McKee M.F.
        • Monnat K.
        • Sampson H.J.
        • Smith C.M.
        • Davies G.A.
        • Mandt L.
        • et al.
        Microbial contamination of hydrophilic contact lenses. Part I: Quantitation of microbes on patient worn-and-handled lenses.
        CLAO J. 1992; 18: 87-91
        • Mowrey-McKee M.F.
        • Sampson H.J.
        • Proskin H.M.
        Microbial contamination of hydrophilic contact lenses. Part II: quantitation of microbes after patient handling and after aseptic removal from the eye.
        CLAO J. 1992; 18: 240-244
        • Pittet D.
        • Dharan S.
        • Touveneau S.
        • Sauvan V.
        • Perneger T.V.
        Bacterial contamination of the hands of hospital staff during routine patient care.
        Arch Intern Med. 1999; 159: 821-826
        • Radford C.F.
        • Minassian D.
        • Dart J.K.
        • Stapleton F.
        • Verma S.
        Risk factors for nonulcerative contact lens complications in an ophthalmic accident and emergency department: a case–control study.
        Ophthalmology. 2009; 116: 385-392
        • Ly V.T.
        • Simmons P.A.
        • Edrington T.B.
        • Wechsler S.
        • De Land P.N.
        Efficacy of hand washing procedures on bacterial contamination of hydrogel contact lenses.
        Optom Vis Sci. 1997; 74: 288-292
        • McGinley K.J.
        • Larson E.L.
        • Leyden J.J.
        Composition and density of microflora in the subungual space of the hand.
        J Clin Microbiol. 1988; 26: 950-953
        • Lakkis C.
        • Lian K.Y.
        • Napper G.
        • Kiely P.M.
        Infection control guidelines for optometrists 2007.
        Clin Exp Optom. 2007; 90: 434-444
        • Larragoiti N.D.
        • Diamos M.E.
        • Simmons P.A.
        • Edrington T.B.
        A comparative study of techniques for decreasing contact lens storage contamination.
        J Am Optom Assoc. 1994; 65: 161-163
        • Illingworth C.D.
        • Cook S.D.
        Acanthamoeba keratitis.
        Surv Ophthalmol. 1998; 42: 493-508
        • Moore M.B.
        • McCulley J.P.
        • Newton C.
        • Cobo L.M.
        • Foulks G.N.
        • O’Day D.M.
        • et al.
        Acanthamoeba keratitis: a growing problem in soft and hard contact lens wearers.
        Ophthalmology. 1987; 94: 1654-1661
        • Jeong H.J.
        • Yu H.S.
        The role of domestic tap water in Acanthamoeba contamination in contact lens storage cases in Korea.
        Korean J Parasitol. 2005; 43: 47-50
        • Seal D.V.
        • Stapleton F.
        • Dart J.K.G.
        Possible environmental sources of Acanthamoeba keratitis in contact lens wearers.
        Br J Ophthalmol. 1992; 76: 424-427
        • Levy B.
        • Heiler D.
        • Norton S.
        Report on testing from an investigation of fusarium keratitis in contact lens wearers.
        Eye Contact Lens. 2006; 32: 256-261
        • Stapleton F.
        • Dart J.K.G.
        • Minassian D.
        Risk factors in contact lens related ulcerative keratitis.
        ARVO Abstract (Supplto Invest Ophthalmol Vis Sci). 1992; 33: 1210
        • The College of Optometrists London
        Contact lens: look after your eye. London.
        2009 (updated 2009. Available at:) ([accessed 29.07.09])
        • LaFollette A.
        How to sterilize contact lens case. eHow Health.
        2013 (Available at:) ([accessed 10.03.13])
        • Hiti K.
        • Walochnik J.
        • Faschinger C.
        • Haller-Schober E.M.
        • Aspock H.
        Microwave treatment of contact lens cases contaminated with acanthamoeba.
        Cornea. 2001; 20: 467-470
        • Wu Y.T.
        • Zhu H.
        • Willcox M.
        • Stapleton F.
        Removal of biofilm from contact lens storage cases.
        Invest Ophthalmol Vis Sci. 2010; 51: 6329-6333
        • Wu Y.T.
        • Zhu H.
        • Willcox M.
        • Stapleton F.
        Impact of cleaning regimens in silver-impregnated and hydrogen peroxide lens cases.
        Eye Contact Lens. 2011; 37: 365-369
        • Boost M.
        • Shi G.S.
        • Cho P.
        Adherence of acanthamoeba to lens cases and effects of drying on survival.
        Optom Vis Sci. 2011; 88: 703-707
        • Wu Y.T.
        • Zhu H.
        • Willcox M.
        • Stapleton F.
        Impact of air-drying lens cases in various locations and positions.
        Optom Vis Sci. 2010; 87: 465-468
      3. Warm Contact; 2011, updated 2011. Available at: http://www.warmcontact.com/ [accessed 04.03.12].

        • Willcox M.D.P.
        • Zhu H.
        • Vijay A.K.
        Effect of a warming device on contact lens case contamination.
        Eye Contact Lens. 2012; 38 (10.1097/ICL.0b013e318261aa13): 394-399
        • de Oliveira P.R.
        • Temporini-Nastari E.R.
        • Ruiz Alves M.
        • Kara-Jose N.
        Self-evaluation of contact lens wearing and care by college students and health care workers.
        Eye Contact Lens. 2003; 29: 164-167
        • Hickson-Curran S.
        • Chalmers R.
        • Sencer S.
        Making the case for daily disposable contact lenses: patient non-compliance with storage case hygiene and replacement.
        American Academy of Optometry, San Francisco, USA2010 (p. Program Nr:105872)
        • Mayers M.
        • Callan B.
        Borazjani Rea. Compliance and contamination in contact lens wear.
        American Academy of Optometry, 2010 (Program Nr:105090)
        • Woods C.
        • Dumbleton K.
        • Richter Dea.
        Compliance with lens care and contact lens case care and replacement.
        in: American Academy of Optometry meeting, San Francisco, USA2010 (Program Nr:100194)
      4. FDA executive summary prepared for the May 13, 2014 meeting of the ophthalmic devices panel of the medical devices advisory committee contact lens and care product guidance documents.
        Food and Drug Administration, USA2014 (updated 2014. Available at:) ([accessed 23.01.15])