Contact Lens Users Research Articles

Efficacy and safety study of an eyelid gel after repeated nocturnal application in healthy contact lens users and non-users

PurposeTo evaluate skin biocompatibility of a nighttime hydrating eyelid gel and possible ocular surface effects in contact lens users (CLU) and non-contact lens users (NCLU). The formulation is registered as a medical device as Tridocosahexaenoine-AOX® (TDHA-AOX) (a concentrated DHA triglyceride), containing also hyaluronic acid (HA). MethodsA prospective, randomized, masked clinical trial was performed with 62 participants of both sexes, aged 20–70 years, split into: (1) CLU (n = 30) and (2) NCLU (n = 32). All participants were instructed to apply a single dose of the moisturizing gel (containing TDHA-AOX and HA) nightly to the upper and inner eyelids of their right eye (RE) only, and during 2 consecutive weeks. Personal interviews, questionnaires, ophthalmic examinations and reflex tear collection were performed. Ophthalmological parameters included ocular surface response and contact lens status. Levels of satisfaction/adverse events were also recorded. Biochemical parameters included basal and final determination of pro-inflammatory mediator molecules in tear samples by multiplex analyses. Statistics were done by the SPSS 24.0 program. ResultsThe CLU group had higher OS dysfunction than NCLU, but overall clinical parameters (corneal staining, and Schirmer/FBUT tests) and OSDI scores showed significant improvement in CLU individuals as compared to the NCLU participants, at the end of study. CLDEQ-8 scores pinpointed significant amelioration in initial risk of developing DEs by applying eyelid gel. Multiplex analyses demonstrated significantly lower VEGF expression levels (p < 0,05) in tears among the CLU compared to NCLU after nightly application of eyelid gel. ConclusionsEyelid gel appeared to safely and efficiently provide hydration and decongestion of the skin and amelioration of the ocular surface during sleep.

Conjunctival Vascular Adaptation Related to Ocular Comfort in Habitual Contact Lens Wearers

We sought to investigate the bulbar conjunctival vascular responses in habitual contact lens (HCL) and non-contact lens (NCL) wearers after short-term lens wear and their relationships with ocular comfort. A prospective, comparative before-and-after study. Twenty-seven subjects (13 HCL and 14 NCL wearers) were enrolled. Microvasculature and microcirculation on the temporal bulbar conjunctiva were imaged at baseline and 0.5 and 6 hours after wearing contact lenses (1-Day Acuvue TruEye; base curve, 8.5mm; power,-0.50 diopters) on both eyes. The measurements included vessel diameter (D), axial (VA), and cross-sectional (VS) blood flow velocities, blood flow volume (Q), and vessel density (Dbox) and complexity (D0). A Contact Lens User Experience (CLUE) questionnaire was used to assess ocular comfort. No significant change (P > .05) was observed in D, VA, VS, Q, Dbox, and D0 in the HCL wearers after contact lens wear. By contrast, VA, VS, Q, Dbox, and D0 increased significantly after lens wear (after 0.5 and 6 hours) in NCL wearers compared with baseline (P < .05). Moreover, the changes from the baseline to 0.5 hours (VA, VS, and Dbox) and 6 hours (VA, VS, Q, Dbox, and D0) after contact lens wear in NCL wearers were significantly greater than that in HCL wearers (P < .05). The CLUE score 6 hours after lens wear was higher in HCL wearers than in NCL wearers (P < .05). It was also significantly correlated with VA, VS, and D0 after 6-hour lens wear in HCL wearers (P < .05). This is the first study to reveal the relationship between ocular comfort and conjunctival vascular responses in habitual contact lens wearers.

The effect of gaming on accommodative and vergence facilities after exposure to virtual reality head-mounted display

BackgroundTo investigate the change between accommodative and vergence facilities before and after exposure to gaming in a virtual reality (VR) device amongst participants with normal binocular visual function. Methods62 participants between the ages of 18–30 years with normal binocular visual function and inter-pupillary distances between 51 and 70 mm were selected for the study. Spectacle and contact lenses users were excluded. The experimental group (n = 42) was exposed to gaming using Samsung Gear VR(SM -R323) whilst the control group (n = 20) watched a television film projected on a two-dimensional screen at 1 m. Pre-test and post-test binocular amplitude-scaled facilities and vergence facilities were obtained for both groups after exposures of 25 min. ResultsBinocular accommodative facilities for the experimental group had a mean pre-test and post-test facility of 11.14 ± 3.67 cpm and 13.38 ± 3.63 cpm, respectively, after gaming using VR device. The vergence facilities for the experimental group had a mean pre-test and post-test facility of 11.41 ± 3.86 cpm and 15.28 ± 4.93 cpm, respectively, after gaming using a VR device. Binocular accommodative facilities for the control group had a mean pre-test and post-test facility of 11.70 ± 3.2 cpm and 11.95 ± 3.4 cpm, respectively. Vergence facilities for the control group had a mean pre-test and post-test facility of 11.55 ± 6.4 cpm and 11.70 ± 4.9 cpm, respectively. The mean change for binocular accommodative facilities was 2.24 ± 3.43 cpm and 0.25 ± 1.25 cpm for the experimental and control group, respectively. The mean change for vergence facilities was 3.81 ± 3.09 cpm and 0.15 ± 2.72 cpm for the experimental and control group, respectively. Binocular accommodative facilities and vergence facility showed a statistically significant mean increase greater than the control group after gaming using a VR device using an independent t-test (p < 0.05). ConclusionThe results showed that binocular accommodative facilities and vergence facilities increased after 25 min of VR gaming in emmetropic participants under 30 years of age with inter-pupillary distances between 51 mm and 70 mm.

Hongos y archivos de papel. Caso clínico sobre queratitis fúngica en una paciente documentalista

A description of a case is presented on a relationship between paper-based documents as a risk factor for fungal keratitis. A 32-year-old woman, a long-term contact lens user, presented with fungal keratitis in her right eye caused by Fusarium spp. while working with books and old documents as a librarian. Her visual acuity was hand motion in the right eye. She was satisfactorily treated with topical antifungal and antibiotic agents.

Assessment of Corneal Epithelial Thickness in Chronic Contact Lens Users Using Anterior Segment Optical Coherence Tomography

Abstract Introduction The corneal epithelium is stratified epithelium that is continuously renewed and provides the frontline of defence against invading ocular pathogens and a smooth refractive surface essential for vision. In the absence of a contact lens, pre-existing ocular trauma or disease, the epithelium maintains an inaccessible defence against attacks from pathogenic microorganisms, affording a high level of resistance against microbial invasion. Aim The aim of this study is to determine the effect of chronic use of contact lens on corneal epithelium thickness using anterior segment optical coherence topography as a non- invasive diagnostic accurate measure. Patients and Methods 30 eyes of control subjects who don’t wear contact lens along their life aged between 15-45 years ,where compared with similar age group of 30 eyes of chronic contact lens users; who wear contact lens every day not less than 8 hours per day for along time interval between 6 months up to 5 years. Results The average corneal epithelial thickness in the central, paracentral and midperipheral zones was 47.767 ± 5.550 µm, 46.267 ± 5.644 µm, 44.300 ± 4.858 µm, respectively, in chronic soft contact lens users; and 49.800 ± 3.316 µm, 49.200 ± 3.367 µm, 45.733 ± 2.333 µm ,in control group who had never worn contact lens. There were insignificant thinning of corneal epithelium of soft contact group compared to control group regarding the average corneal epithelial thickness in those 3 zones. In all the 8 sectors of corneal epithelium of paracentral zone and midperipheral zones there is insignificant thinning between the two groups except for the inferior temporal sector in the paracentral zone and mid peripheral zone, which shows significant thinning in soft contact lens group compared to control group. The corneal epithelial thickness in the inferior temporal sector of paracentral and mid peripheral zones was 46.333 ± 5.677 µm, 44.933 ± 4.813 µm, respectively, in chronic soft contact lens users compared to 48.767 ± 3.266 µm, 46.900 ± 2.510 µm in control group (p = 0.046, p = 0.052, respectively). Conclusion AS-OCT helps us to evaluate the corneal epithelium of contact lens users, which could be very useful in corneal refractive surgeries in patients depending on contact lens in their lives as a comfortable refractive aid, It is necessary to do AS-OCT hand on hand with pentacam in patients underwhelming refractive surgery to give a proper assessment to their corneal epithelium before determining which type of refractive surgery suits them.

A survey on knowledge and attitude of Saudi female students toward refractive correction

BackgroundTo assess the general knowledge and attitude of refractive error correction methods among female Saudi university students.MethodsOne thousand, one hundred and sixty‐five female university students, between 17 and 32-years of age were randomly interviewed using self‐administered questionnaires with open and closed‐ended questions. The questions collected information on demographics (gender, age, educational status, college of study, and occupation), addressed general knowledge/perception of the difference between the professions of ophthalmology and optometry, and attitudes toward spectacle, contact lens (CL) usage, including coloured prescription CLs, and refractive surgery for correcting refractive errors.ResultsThe response rate was 90-per cent (1,052/1,165). Fifty‐two per cent had never had an eye examination and only 28-per cent correctly identified the difference between an ‘ophthalmologist’ and ‘optometrist’. Eighty‐one per cent knew that CLs instead of spectacles (81.8-per cent), and coloured CLs (89.7-per cent) can be used for correcting refractive errors. Concerning refractive surgery, although a majority (90-per cent) knew that the technique corrects refractive error and reduces dependency on spectacles/CLs, only five-per cent had experienced refractive surgery. Approximately, 46-per cent and 47-per cent used spectacles and CLs, respectively, and while the optometrist was the main source of CL prescriptions (41-per cent), most people visited the ophthalmologist for their eye examination (68-per cent). Surprisingly, 52-per cent had never had an eye examination, or had only had one or two eye examinations (50-per cent) in their lifetime. While 23-per cent of spectacle wearers chose to continue with spectacles at the end of the study, 64-per cent and 12-per cent preferred refractive surgery and CLs, respectively, for refractive correction. Lack of information and fear of complications, but not cost, hindered most people from uptake of CLs and refractive surgery.ConclusionThe students demonstrated high levels of knowledge and awareness of refractive correction methods, especially for refractive surgery. Although many consulted the optometrist or ophthalmologist for their eye examinations and corrective devices, many remain uncorrected and unaware of the main difference between both professions. The lack of information about correction methods and fear of complications may have affected their interest in uptake of eye services and should be addressed to increase uptake and prevent avoidable vision loss.

Treating Uncomfortable Contact Lens Wear With Orthokeratology.

Many contact lens (CL) users permanently discontinue wear because of ocular dryness and discomfort. This study aimed to determine whether refitting symptomatic soft CL wearers in to orthokeratology could improve ocular symptoms and signs. This was a prospective, 3-month, open-label study of symptomatic (Contact Lens Dry Eye Questionnaire [CLDEQ-8] ≥12) soft CL wearers who were between the ages of 18 and 45 years. All subjects were refit into orthokeratology CLs (Emerald, Euclid Systems). The following tests were completed: CL history, Standardized Patient Evaluation of Eye Dryness (SPEED) questionnaire, CLDEQ-8, CLDEQ-4, logarithm of the minimum angle of resolution visual acuity, pupil size, refractive error, slit-lamp biomicroscopy, noninvasive tear break-up time, tear meniscus height, phenol red thread, conjunctival staining, corneal aesthesiometry, and corneal topography. Twenty-nine of 40 qualifying subjects (age=24.43±4.62 years) completed the study. No significant differences were detected between completed and noncomplete subjects. Completed subjects had significantly better CLDEQ-8, CLDEQ-4, and SPEED scores at 3 months compared with baseline. Completed subjects had significantly better conjunctival staining scores and flatter keratometry values at 1 month compared with baseline. Although not all symptomatic soft CL wearers were able to be refit into orthokeratology, subjects who were wearing orthokeratology at 3 months had a significant and clinically meaningful improvement in ocular symptoms. Additional work is needed to determine the mechanism leading to improved comfort because few clinical signs were changed after switching to orthokeratology.

Novel anti-biofouling and drug releasing materials for contact lenses

Contact lens users very often become patients of allergic conjunctivitis, which is caused by protein and bacteria adsorption to the eye, because contact lenses easily adsorb proteins and bacteria. However, even if contact lens users develop eye diseases such as allergic conjunctivitis, most of them continue to use contact lenses to avoid interference to daily life or a decrease in their quality of life. If novel contact lenses able to prevent and additionally cure eye diseases can be manufactured, they could improve the quality of life of contact lens users worldwide. Thus, we aim to develop a novel material for contact lenses to prevent diseases by incorporating a zwitterionic polymer with the ability to suppress protein and bacteria adsorption. In addition, we also aim to effectively introduce and release a drug against allergic conjunctivitis from the contact lens material. Because the poorly water-soluble drug for allergic conjunctivitis (pranoprofen) forms a rigid crystal structure, we developed the novel “hot-melt press method” to construct a contact lens able to effectively release it. In the present study, polymer sheets containing carboxymethyl betaine (a kind of zwitterionic monomer), 2-hydroxyethyl methacrylate, and 1-vinyl-2-pyrrolidone were prepared using three different procedures. The sheets were hydrophilic and showed a strong resistance against protein and bacteria adsorption. The sheets prepared by the hot-melt press method were transparent and seemed to have potential as a material for contact lenses. In addition, the drug introduced into the sheets during preparation was observed to release at a practically appropriate dose. Therefore, it is expected that the sheets could possibly be used as a material for contact lenses which not only protect against the development of eye trouble due to protein and bacterial adsorption, but also heal allergic conjunctivitis.

Preparation, Characterization, and Evaluation of Zinc Oxide Nanoparticles Suspension as an Antimicrobial Media for Daily Use Soft Contact Lenses

ABSTRACT Purpose Infection and inflammation during wearing contact lenses are the problems for the users of daily soft contact lenses. All Gram-positive bacteria, Gram-negative bacteria, and fungi play a role in this problem. In past decades, nanoparticles have largely been studied and shown good antimicrobial activity against various microorganisms. The present study aimed to prepare, characterize, and evaluate zinc oxide nanoparticles (ZNPs) as antimicrobial agents against different microorganisms. Materials and Methods The ZNPs were synthesized in a special structure using the sol-gel process and characterized by XRD, TEM, and EDX. Antimicrobial properties of ZNPs suspension were investigated against different microorganisms (i.e., Staphylococcus aureus, Staphylococcus epidermidis, Listeria monocytogenes, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli, and Candida albicans) by the Scanning Electron Microscopy of lens surfaces and pour plate method of immersed lens suspension for microbial enumeration. Results The XRD, TEM, and EDX spectrum showed hexagonal structure and no impurity in the nanoparticles with a size of about 20 to 40 nanometers. Sterilized suspension of ZNPs was applied against bacterial species, and the results indicated 4 logarithms (CFU/mL) microbial growth reduction for most Gram-positive and Gram-negative species, except for Pseudomonas aeruginosa that showed 3.5 logarithms (CFU/mL) growth reduction. Furthermore, 1 and 1.7 logarithms (CFU/mL) growth reduction were observed for Candida albicans, applying 250 and 500 ppm ZNPs suspension, respectively, which is an acceptable result for fungal growth inhibition. Findings of this study indicated that the suspensions of ZNPs with 250 and 500 ppm showed acceptable bacteriostatic and bactericidal effects. Conclusions In vitro antimicrobial activity showed that the suspension of ZNPs with 250 ppm concentration could effectively cause a proper reduction and inhibition in the growth of both Gram-positive and Gram-negative microorganisms. Therefore, the results revealed the efficacy of the antibacterial properties of synthesized ZNPs suspension in aqueous media. Abbreviations ZNPs: Zinc oxide nanoparticles; XRD: X-ray diffraction; FWHM: Full width at half maximum; TEM: Transmission electron microscope; SEM: Scanning electron microscope; EDX: Energy-dispersive X-ray spectroscopy; S. aureus: Staphylococcus aureus; S. epidermidis: Staphylococcus epidermidis; L. monocytogenes: Listeria monocytogenes; B. subtilis: Bacillus subtilis; P. aeruginosa: Pseudomonas aeruginosa; S. typhi: Salmonella typhi; E. coli: Escherichia coli; C. albicans: Candida albicans; MK: Microbial keratitis; CLARE: Contact lens-induced acute red eye; CLPU: Contact lens-induced peripheral ulceration; IK: Infiltrative keratitis; AIK: Asymptomatic infiltrative keratitis; MIC: Minimum inhibitory concentration; MBC: Minimum bactericidal concentration; BHI: Brain heart infusion; TSB: Tryptic soy broth; BHIA: Brain heart infusion agar; TSA: Tryptone soya agar.

Combination of tert-butyl hydroperoxide with vorinostat induces cell death of Acanthamoeba through cell cycle arrest

Safety precautions prior to contact lens usage is essential for preventing Acanthamoeba keratitis. Contact lens disinfecting solutions containing 3% hydrogen peroxide (H2O2) are known to exert amoebicidal effect against Acanthamoeba. Yet, these solutions need to be neutralized to prevent ocular irritation, which consequently may result in incomplete disinfection. In this study, amoebicidal effect of tert-butyl hydroperoxide (tBHP) was investigated and its efficacy was compared to those of hydrogen peroxide (H2O2). H2O2 and tBHP showed dose dependent amoebicidal effect, however high concentration of these compounds demonstrated cytotoxicity in human corneal epithelial (HCE) cells. To reduce their cytotoxicity, the concentrations of both compounds were diluted to 50 μM and subsequently combined with 10 μM vorinostat to enhance amoebicidal effect. Addition of vorinostat induced high amoebicidal effect against Acanthamoeba trophozoites, even at low concentrations of H2O2 or tBHP. Cellular damage induced by combined treatment of H2O2 or tBHP with vorinostat in Acanthamoeba were determined by assessing cell cycle arrest and apoptosis via FACS analysis. While 50 μM H2O2 combined with 10 μM vorinostat showed 36.26% cytotoxicity on HCE cells during 24 h exposure, 50 μM tBHP with 10 μM vorinostat did not show cytotoxicity on HCE cells. These findings suggest that the application of tBHP and vorinostat for Acanthamoeba keratitis treatment and contact lens disinfection system is highly plausible.

Tear Film Dynamics of Soft Contact Lens-Induced Dry Eye

ABSTRACT Purpose This study aimed to prospectively assess tear dynamics in soft contact lens-induced dry eye while wearing and after removing the soft contact lenses. Materials and Methods We analyzed 17 right eyes of soft contact lens users at Wada Eye Clinic (11 men, 6 women; mean age: 36.8 ± 8.3 years; range: 24–57 years). Participants were divided into two groups depending on presence of dry eye symptoms. Video interferometry was used to observe tear dynamics while wearing and after removing soft contact lenses. Interference images focusing on tear spread and interference fringe were compared between groups. Results This study included 10 symptomatic and 7 asymptomatic eyes. Considering the symptomatic eyes, while wearing soft contact lenses, 8 eyes showed poor tear spread and multicolor interference fringe, i.e., swift flow of multicolor interference waves after a grayish monochromatic band-color after a blink, but 8 and 10 eyes showed good tear spread and a grayish monochromatic interference fringe when soft contact lenses were removed, respectively. As for asymptomatic eyes, 6 eyes exhibited good tear spread and a grayish monochromatic interference fringe while wearing soft contact lenses and after removing soft contact lenses. Conclusions soft contact lens-induced dry eye was associated with tear dynamics only while wearing soft contact lenses. Observation of tear film dynamics in eyes with soft contact lenses could facilitate the understanding of dry eye-related symptoms.

Влияние препарата «Катионорм» на слезную пленку при обструктивной дисфункции мейбомиевых желез у пользователей мягких контактных линз

There are more than 80 million users of soft contact lenses in the world - 10-15 % of the population. The prevalence of meibomyus gland dysfunction is 43-61 % with the prevalence of obstructive form and the development of lipodeficiency in lacrimal film. At the same time, the use of traditional tear substitutes based on hyaluronic acid is ineffective and the problem of finding a tear substitute with exposure to all 3 layers of lacrimal film becomes relevant. Nanoemulsion “Cationorm” is created as a means of pathogenetic therapy of dry eye syndrome against the background of lipodeficiency, however, there weren't any studies of its effectiveness in obstructive form of meibomyus gland dysfunction among users of soft contact lenses. We examined 3 layers of lacrimal film with the help of Norn's sample with determination of time of lacrimal film break, bio-measurement of lacrimal meniscus and biomicoscopy of eyelid edge region at painting of lissamino-om green. The study involved 28 young carriers of silicone-hydrogel contact lenses with signs of obstructive form of meibomyus gland dysfunction, who we divided into two groups: a control group used to eliminate the symptoms of a hyaluronic acid-based tear substitute, and an experimental group using the drug “Cationorm”. We revealed prolonged effect of nanoemulsion “Cationorm” on all three layers of lacrimal film, which hasn't only symptom lacrimal, but has pathogenetic therapeutic delayed effect among users of soft contact lenses with obstructive form of dysfunction of meibomyum glands, and nanostimer of lipid microspheres provides full compatibility even with material of silicone-hydrogel soft contact lenses. We proved the protective effect of the preparation on ocular epithelium cells.

Razlozi za razvoj komplikacija kod korisnika mekih kontaktnih sočiva - kvalitativna studija

Objective. To determine reasons and their actual role in occurrence of complications in users of soft contact lenses. Methods. This was a qualitative study in which a constructivist grounded theory approach was used to analyze obtained data. The study population consisted of two groups of subjects: 10 students who were identified as users of soft contact lenses and 4 ophthalmologists. Each of the respondents participated ina single interview. Based on audio recordings of these interviews appropriate transcripts of conversations were made and analyzed. After elimination of waste words 11 key categories were crystallized. Results. Recommendations of the ophthalmologists perhaps have the decisive role in the formation of attitude that users will have regarding the adequate hygiene of soft contact lenses: hand hygiene, proper cleanliness of storage for soft contact lenses and using the solution in the allotted time are imperative for users of soft contact lenses. Sleeping with soft contact lenses for a long period and more frequently than it was specified in the recommendation of an ophthalmologist is one of the greatest reasons for development of dry eye symptoms, while swimming with soft contact lenses increases the risk for occurrence of eye infections. Conclusion. The main reasons for the occurrence of complications in soft contact lenses users are inadequate hygiene and weakening of compliance of soft contact lenses users over time.

Clinical presentations, genotypic diversity and phylogenetic analysis of Acanthamoeba species causing keratitis.

Introduction. Acanthamoeba keratitis is a sight-threatening corneal infection that is commonly reported among contact lens users and those suffering from corneal trauma. The prevalence of Acanthamoeba species or genotypes in causing keratitis infection is not well known.Aim. This study was conducted to identify and genotype Acanthamoeba isolates from keratitis patients, targeting the ribosomal nuclear subunit (Rns) region, and describe the associated clinical presentation and treatment outcome.Methodology. Thirty culture-confirmed patients with Acanthamoeba keratitis, identified in a tertiary eye care centre in South India during the period from December 2016 to December 2018, were included in this study. The data collected from patient records include demographic details, history of illness, mode of trauma, treatment history and follow-up status. The genotype and species were identified based on the Rns sequence and phylogenetic tree analysis.Results. Acanthamoeba culbertsoni was the most predominant keratitis-causing species, followed by Acanthamoeba quina, Acanthamoeba castellanii, Acanthamoeba healyi, Acanthamoeba hatchetti, Acanthamoeba polyphaga and Acanthamoeba stevensoni. Three major genotypes were identified (T4, T11 and T12), with the T4 genotype being the most predominant, with four subclusters, i.e. T4A, T4B, T4D and T4E. This is the first report on corneal infection by the A. stevensoni T11 genotype and the A. healyi T12 genotype. No significant correlation was observed between the clinical outcomes of corneal disease and the genotypes or species.Conclusion. Rns genotyping is very effective in identifying the Acanthamoeba species and genotype in keratitis. Genotyping of Acanthamoeba spp. will help to advance our understanding of genotype-specific pathogenesis and geographical distribution.

Comparison of Ocular Microbiome in Noncontact Lens and Contact Lens Users

Comparison of Ocular Microbiome in Noncontact Lens and Contact Lens Users

Spectrum of Microbial Keratitis Encountered in the Tropics.

To report the predisposing factors, microorganisms, antibiotic sensitivity associated with bacterial keratitis, and treatment outcomes in Miri, Borneo which has a tropical climate. This is a retrospective study on patients presenting with microbial keratitis in Miri, Sarawak, Borneo over a 7-year period from January 1, 2010 until December 31, 2016. Demographic data, predisposing factors, culture and sensitivity results together with treatment outcomes were studied. There were a total of 221 cases treated as microbial keratitis with a peak age group of 21 to 30 years. The predisposing factors were trauma (49.3%), improper contact lens usage (29.1%), ocular surface diseases (5.9%), ocular surgeries (0.9%), drugs (1.8%), and other factors (19.0%). Occupational injuries among oil palm plantation workers was the leading cause within the trauma cohort (28.8%). Corneal scraping was performed in 189 cases, 61.4% of them yielded positive cultures. The cultures demonstrated that 49.1% were of bacterial origin, 46.6% were fungal, and 4.3% showed mixed growth. The most common bacteria isolated was Pseudomonas aeruginosa, which was sensitive toward ceftazidime and gentamicin antibiotics. One hundred ninety-two cases (86.9%) were treated with purely topical medication, whereas 29 cases (13.1%) required further interventions. The commonest predisposing factor for microbial keratitis was trauma. With the nearby oil palm industries, we report a corresponding increase of incidence in fungal keratitis at our center. Culture and sensitivity reports from corneal scrapings are essential in treatment guidance; however, more than a third of the microbial keratitis cases studied were culture-negative. The organisms cultured reflect the profile expected in tropical climates. Fortunately, there was no increase in resistance rates observed for the commonly used antibiotics.

Intraocular devices associated adverse events reporting system in India.

Intraocular devices associated adverse events reporting system in India.

Increasing incidence of Acanthamoeba keratitis in a large tertiary ophthalmology department from year 1994 to 2018.

Acanthamoeba (AA) keratitis is a rare and severe infection with poor prognosis. The aim was to investigate the incidence and risk factors of AA keratitis in a large tertiary ophthalmology department in Denmark. A search was performed in our electronic patient records by the keywords: 'PHMB/polyhexanid', 'Brolene' or 'amoeba and chlorhexidine' from year 1994 to 2018, and afterwards medical records were reviewed. A total of 65 cases of AA keratitis were hereby identified. Patients were relatively young, median (range) age of 38 (15-70)years. A significant increase of diagnosing AA keratitis occurred from 0.13 cases per million per year in the first 5years to 2.7 cases per million per year the last 5years. Eighty-nine per cent of patients were contact lens users, and 49% had received corticosteroids before the diagnosis was established. Severe pain was present in 34% of patients. Prognosis was poor with final visual acuity of logMAR (mean, 95% CI) 0.30 (0.18-0.41), 18% had transplantation à chaud, and 2% were enucleated. The study indicates that the incidence of AA keratitis is increasing, also in Denmark. Most patients were young contact lens users. The course of the disease is long and often painful, and the prognosis is poor despite relevant treatment.

Comparison of microbiome isolated from the conjunctiva, contact lens and lens storage case of symptomatic and asymptomatic contact lens users

Contact lenses (CLs) are increasingly being used for cosmetic or therapeutic purposes. Lack of compliance and poor hygiene towards lens care is strongly associated with microbial contamination and has been proved to result in eye infections. The present study was done to compare the microbial flora between symptomatic and asymptomatic contact lens users. The study also attempts to analyze the contact lens hygiene practices of CL users. Six samples each were collected from both the eyes, CLs and lens cases of 40 CL users (n=240) divided into two groups based on symptoms present asasymptomatic CL users and symptomatic CL users. Organisms were identified using standard microbiological techniques. The proportion GNB obtained in symptomatic CL users was significantly higher when compared to asymptomatic CL users (p-value= <0.003). In 56.2% eyes, the microbial flora of conjunctiva was similar to either the contact lens isolate/storage case. Enterococcal microbial keratitis was seen in one case. There was significant microbial contamination present in CL users despite compliance to contact lens hygiene practices. There were a significant number of bacteria (p-value <0.001) present which were resistant to ampicillin, amoxicillin-clavulanate, and cefotaxime in both the groups.

Light distortion of soft multifocal contact lenses with different pupil size and shape

PurposeTo study the light distortion effects of soft multifocal contact lenses and the influence of different pupil size and shape. MethodsA total of 14 eyes of 7 healthy contact lens users (mean age 28.6 ± 8.5 years) were recruited. The “Light Disturbance Analyser” device was employed for light characterization. The selected lenses were the monthly disposable “Biofinity multifocal” (CooperVision, CA, USA), both centre-distance and centre-near designs (addition power +2.50 D). Two circular pupils of 3 mm and 5 mm of diameter, and an elliptical shape (3 horizontal and 5 vertical mm) were used. Metrics such as the light distortion index (LDI), best-fit circle radius and its irregularity were analysed, among others. ResultsThe LDI was generally higher with multifocal lenses, varying from 3.7 ± 0.3 % of the single vision lens to 6.1 ± 3.3 % of the multifocal centre-distance design and the 5-mm pupil. Larger pupils gave higher LDI values, changing from 4.5 ± 2.0 % (3 mm) to 6.1 ± 3.3 % (5 mm) with the centre-distance design. The elliptical pupil produced the largest discrepancy in the distortion size between the vertical and horizontal directions. The centre-distance and centre-near designs behaved similarly in terms of light distortion. ConclusionsThe multifocal contact lenses of the study increased light distortion effects under low light conditions, especially with larger pupils. The shape of the distortion pattern is associated with the shape of the pupil. It seems that not all, but a big percentage of light distortion would be produced by the presence of the out-of-focus images given by a multifocal lens.