CL Wearers Research Articles

The analysis of tear meniscus parameters during daily soft contact lens wear using optical coherence tomography.

To evaluate tear meniscus parameters in soft contact lens wearers (SCL) using optical coherence tomography (OCT) and ImageJ software. This prospective study included 50 soft contact lens wearers (group 1: 25 symptomatic SCL wearers (SCLW), group 2: 25 asymptomatic SCL wearers (ASCW)) and 25 healthy non-CL wearers (group 3 (NCLW)). SCLs were fitted on each eye of CL wearers, and the lower tear meniscus was imaged using OCT before CL insertion, immediately afterward, and reimaged 2, 5 and 10h after insertion. Tear meniscus parameters, including tear meniscus height (TMH), depth (TMD), turbidity, and percentage area occupied by particles (PAOP) were measured in all groups. Turbidity and PAOP measurements at baseline in SCLW were significantly higher than in other groups (p < 0.05). There was no significant difference between TMH, TMD, turbidity, and PAOP parameters calculated at baseline visit and two hours after SCL insertion in all groups (p > 0.05 for 2 comparisons). The symptomatic SCL users had a significant decrease in TMH and TMD in the fifth hour. The turbidity and PAOP measurements of SCLW and ASCW at the fifth and tenth hours were significantly higher than those of NCLW (p < 0.05). TMD and height TMH decrease throughout the day in all participants; however, a significant decrease in these parameters was observed only in symptomatic SCL users at the fifth hour, at the earliest. As the duration of CL wear increases, turbidity and PAOP even in asymptomatic SCL wearers become significantly higher than those in healthy non-CL wearers. What Is Known • Contact lens wear is associated with an increased risk of dry eye. • Tear volume decreases gradually during contact lens wear. What Is New • Tear meniscus turbidity and particle area occupied by particles (PAOP) were higher in symptomatic contact lens wearers and they increase gradually during contact lens wear. • Tear meniscus turbidity and PAOP may be measures of how well the tear film and meniscus are functioning in contact lens wearers.

Clinical characterisation of contact lens discomfort progression

PurposeThis study aimed to assess the subjective and objective differences among the steps of the contact lens discomfort (CLD) progression classification established by the Tear Film & Ocular Surface Society (TFOS) using questionnaires and clinical signs, and to propose a simplified classification. MethodsContact lens (CL) wearers were evaluated in a single visit. The Contact Lens Dry Eye Questionnaire (CLDEQ)-8, the Contact Lens Discomfort Index, and Visual Analog Scales for discomfort and dryness were administered. The non-invasive break-up time, the tear film lipid layer thickness, conjunctival hyperaemia and papillae, lid-parallel conjunctival folds, the fluorescein tear film break-up time, corneal and conjunctival staining, lid wiper epitheliopathy, and the Schirmer test were assessed. Sign and symptom scores were compared among TFOS CLD progression steps using analysis of variance or the Kruskal–Wallis H test. Steps 1 and 2 (reduced comfort), and steps 3 and 4 (reduced wearing time) of the TFOS classification were combined to obtain a simplified classification, and the same comparison was performed. A p-value ≤ 0.05 was considered statistically significant. ResultsOne hundred-fifty CL wearers (97 women and 53 men) aged 34.4 ± 12.6 years were included. In the TFOS classification, there were significant differences between step 0 (no CLD) and the rest of the severity steps for the scores obtained in all questionnaires (p ≤ 0.015). All steps were differentiated (p ≤ 0.032) based on the simplified classification for all questionnaires, except steps 1 and 2 for the CLDEQ-8 and dryness VAS (p = 0.089 and p = 0.051, respectively). There were no differences (all p ≥ 0.06) between the sign scores among the steps of either classification. ConclusionCLD management is encouraged from its first appearance. Simplifying the phases of CLD severity may allow a more accurate classification and a better awareness of the problem by clinicians and CL wearers by using more straightforward simple messages.

CPD: Strategies to increase success with new soft CL wearers

Adam Samuels, Professor Philip Morgan and Anna Sulley summarise a recent literature review on ways to increase success with new contact lens wearers in practice. (C105963, suitable for logging as one distance learning CPD point for optometrists, contact lens opticians and dispensing opticians)

Efficacy of two contact lens disinfecting solutions in reducing growth rate of bacteria and eradication of biofilms

Efficacy of two types of contact lens disinfecting (CLD) solutions, most frequently purchased from Jordanian pharmacies by contact lens wearers, was investigated for reducing growth rate of methicillin resistant and methicillin sensitive Staphylococcus aureus, Serratia marcesence, S. liquefacience and Acinetobacter spp., previously isolated from In-use disinfecting solutions in CL cases. Each species was cultured in a clean and dirty conditions (to mimic real situation) of two fresh CLD solutions separately: A and B whose active agents are: Polyhexamethylene biguanide hydrochloride and Polyaminopropyl biguanide respectively. Log reduction of these bacteria have exceeded ISO 14729 acceptable criteria (3 log) and reached up to 5 log reduction. Dirty conditions have marked effect in reducing efficacy of CLD solution (A) to kill bacterial species under test. Biofilms produced by S. marcescens and S. liquefaciens were reduced by more than 50% after 24 hrs. using either CLD solutions, though it was less than that reduced after 4 hrs. Biofilm of methicillin resistant Staphylococcus aureus (MRSA) was the most affected by either CLD solutions after 4 hours. This study concluded that CL wearers should pay great consideration to cleaning and disinfection practices to decrease bacterial growth, reduce chances of biofilm formation.

Contact Lens Wearer’s Outlook Towards Recommended Replacement Schedule of Contact Lens in Mumbai

Background: Non-compliance is one of the major reasons of CL related complications. Various research studies have been done over the past three decades to find reasons for patient non-compliances. Use of CLs over the recommended replacement schedule has been one of the major reasons leading to CLs complications. It is evident that the CLs user are often unaware of their non-compliance towards lens care and maintenance regimen. Even after introduction of daily disposable lenses and one-step multipurpose solution non-compliance towards CLs use is still a major problem in CLs patients. The complications due to patient noncompliance can be sometimes irreversible. This research will help us understand CL user reasons of intentionally or unintentionally being non-compliant to recommended replacement frequency.&#x0D; Method: All CL users willing to share their experience participated in this questionnaire based online survey which was designed with the help of focused group discussion.&#x0D; Results: Most of the CL wearer prefer buying pairs for at least 6 months at a time. Almost 80% of CL wearers do not replace their CL as per MRRF. 70% of those who participated wore CL for more than 10 hours per day. The male and female ratio is almost equal in the participants participated in the research.&#x0D; Conclusion: Research done in the past suggest incomplete knowledge imparted to the wearer or CL forgetting the instructions given to them at dispensing. Research also suggest some CL wearer knowingly are non-compliant to MRRF. This study tries to find loopholes in a CL practice by finding reasons of non-compliance as per CL wearers prospective and probable suggestion from the user itself. An ECP is a paramedical person who has the right to prescribe them, whether according to MRRF or as per their knowledge of the patient’s ocular status. For e.g., an antibiotic medicine is supposed to be prescribed for 3 days or 5 days, once or twice is decided by the medical practitioner prescribing. As this research shows over 50% of the CL wearer said that their 'ECP said its okay'.

Microbiota in MGD

AbstractMGD is characterized by significant changes in meibum quality that may lead to the changes in the existing ocular surface flora that can contribute to the inflammatory state typical of the condition. Several papers have addressed this aspect. Li and coworkers, dividing the DE group into MGD and non‐MGD patients, found that no statistically significant differences between the two groups. 67 Pseudomonas, Bacillus, Acinetobacter and Corynebacterium were the most represented, although Bacilli showed a higher relative abundance in the MGD group and could be considered typical pathogens of MGD. Watters and colleagues studied patients with several degrees of MGD, among which CL wearers were included. Meibum expression did not modify the bacterial profile. CoNS were the most prevalent organisms isolated, present in two thirds of the population studied, although their presence was not correlated to the severity of MGD. CL wearers showed an increased presence of P. acnes that was correlated to MGD severity. No differences in microbiota were observed related to the severity of anterior blepharitis or CL wear. Dong and coworkers, using 16 S rDNA sequencing, investigated the microbiome of 47 Chinese MGD patients compared with a control group of 42 sex‐ and age‐matched subjects without MGD. They found significant differences at the phyla level, with a significantly higher abundance of Firmicutes (31.7% vs. 19.7%) and Proteobacteria (27.5% vs. 14.7%), and a lower abundance of Actinobacteria (34.2% vs. 57%) in MGD vs control patients. At the genus level, the numbers of Staphylococcus (20.7% vs. 7.9%) and Sphingomonas (5.7% vs. 0.8%) were significantly higher in patients with MGD vs controls, while the numbers of Corynebacterium (20.2% vs. 46.4%) were significantly lower. The meiboscores showed a significant direct correlation with the abundance of Staphylococcus in MGD patients. They concluded that patients with MGD can have bacterial microbiota alterations in the conjunctival sac, with a potential role of Staphylococcus, Corynebacterium and Sphingomonas sp. in MGD pathophysiology. In a previous study carried out on a small group of patients with blepharitis, Lee and coworkers demonstrated that blepharitis might be associated with a change in microbial composition, namely, greater quantities of Streptophyta, Corynebacterium and Enhydrobacter species. It was suggested that cytotoxicity and inflammatory components, triggered by bacterial growth, may contribute to the pathological process of MGD. Zheng et al confirmed the changes of ocular surface flora in MGD patients showing a wide bacterial profile and positive aerobic and anaerobic culture, significantly higher in both meibomian secretion and conjunctiva of MGD patients than in controls. The ocular surface inflammatory condition occurring in MGD and blepharitis could be mediated by the induced expression of acidic mammalian chitinase (AMCase) that is considered an immune response activator and is over expressed in MGD. It can be hypothesized that changes in ocular surface microbial flora can mediate AMCase upregulation.

Acanthamoeba keratitis in contact lens wearers in a tertiary center of Tunisia, North Africa

PurposeTo analyze the epidemiological and clinical features of Acanathamoeba keratitis AK and to assess the risk factors of this corneal infection in contact lens CL wearers in a tertiary center of Tunisia, North Africa. MethodsWe carried out a retrospective study between January 2008 and December 2019 in the ophthtalmology department of a referral center, Sousse, Tunisia. A review of the chart of 248 patients using CL and diagnosed with presumed infectious keratitis was done.Socio demographic, risk behaviors and microbiological findings in case of AK were analyzed. The mean follow-up was 18 months (1 month–4 years). ResultsAK was diagnosed in 29 cases (11.7% of contact lens wearers with infectious keratitis). These 29 cases were analyzed. The mean age at the time of diagnosis was 33, 44 ± 26, 9 years. Almost of the patients (13; 44.82%) used soft monthly disposable contact lenses. Some risk behaviors related to contact lens wearing were found in our study like not washing and drying hands before CL wear, sleeping in CL, topping off, not respecting the adequate replacement frequency and showering or swimming in CL.After treatment, visual acuity improved only in 10 cases (34.48%), remained the same in 11 cases (37.93%) and worsened in 8 cases (27.58%). ConclusionClinicians must suspect AK in each CL wearer with suggestive clinical signs to allow earlier treatment and better prognosis. Public prevention messages that encourage CL wearers to respect the hygiene rules should be broadly applicable to each person using any type of CL, to minimize the risk of AK.

Eye Blinking Patterns, Corneal Staining and Compliance in a Group of Soft Contact Lens Wearers

Many factors influence the success of contact lens wear, including lens surface moisture, which is affected by blinking. This study was conducted to determine the eye blinking patterns, corneal staining, and compliance in a group of soft contact lens (CL) wearers. Forty-one soft CL wearers and 41 age-matched control subjects (non-CL wearers) were recruited in this study. Blinking patterns were assessed with a digital camera attached to a slit lamp biomicroscope. Corneal staining was graded using Institute for Eye Research (IER) grading scale with 0.1 increments. The subject’s compliance level was determined using a questionnaire. There was no difference in eye blinking patterns between the CL wearers and control group (Mann-Whitney, p = 0.231). The average grades of corneal staining in CL wearers and control group were 0.38 ± 0.39 and 0.01 ± 0.08 unit, respectively. There was a significant difference in corneal staining between the two groups (Mann-Whitney, p = 0.021). A significant positive correlation was found between blinking patterns and corneal staining (Spearman ρ = 0.378, p = 0.015). Our results also showed that 63.4% of the CL wearers had good compliance towards lens care. In our multiple linear regression analysis, blinking patterns contributed significantly to corneal staining (B = 0.140, p = 0.015), while compliance level did not (B = -0.038, p = 0.471). Overall, eye blinking patterns in CL wearers influenced the risk of corneal staining.

Intranasal Neurostimulation for the Treatment of Neurosensory Abnormalities in CL Wearers (INTAC)

Intranasal Neurostimulation for the Treatment of Neurosensory Abnormalities in CL Wearers (INTAC)

Acanthamoeba keratitis: An emerging disease among microbial keratitis in the Cap Bon region of Tunisia

IntroductionThe aim of this study was to describe the prevalence of AK among microbial keratitis as well as their clinical features and to compare their risk factors to those of other infectious keratitis, over the last five years in a referral center in the region of Cap Bon, Tunisia, North Africa. MethodsA retrospective review of the charts of 230 patients (230 eyes) diagnosed with presumed infectious keratitis between January 2011 and December 2016 at the department of ophthalmology of the university hospital of Nabeul in Tunisia. After a detailed ocular examination using standard technique, corneal scrapes were performed under aseptic conditions from each ulcer. Plates were incubated at 30 °C and screened daily for Amoeba.The treatment was adjusted according to the results of microbiological findings and the response of initial treatment.The mean follow up was 11.4 months (1 month–26 months). ResultsA total of 230 corneas were scraped. The prevalence of Acanthamoeba keratitis was 6% (14 cases of 230).All cases of Acanthamoeba keratitis with a history of contact lenses were diagnosed thanks to the test of Contact lenses, their cases or their storage solution, while their corneal scrapings were negative. The corneal scraping was positive for Acanthamoeba only in 4 cases of 14.Acanthamoeba was identified more in young patients (92.8%). Significantly, more patients (54 of 74; 73%) with fungal keratitis and Acanthamoeba keratitis (11 of14; 78.6%) were rural population The most cases of Acanthamoeba keratitis (10 of 14; 71.4%) used contact lenses. Ocular injury was identified in 4 cases of 14 AK (28,5%). Coexistent ocular disease was seen in seven cases of 14 (50%). Of the 230 microbial keratitis, an early diagnosis (≤30 days) was done in 200 cases (86.95%), while a late diagnosis (≥30 days) was made in 30 cases (13%). In AK, most cases (11 of 14; 78,5%) were diagnosed with a delay of more than 30 days. Slit-lamp examination showed stromal infiltrate in 12 cases (85,7%), hypopion in 2 cases (14,3%), immunitary ring in 2 cases (14,3%) and radial keratoneuritis in one case (7,1%). ConclusionContact lenses were identified as the main risk factor of Acanthamoeba keratitis in our study. The diagnosis of AK should be considered in case of atypical keratitis especially among CL wearers in the rural regions of CapBon where the rules of hygiene are not respected.

Tear Film Osmolarity in Response to Long-Term Orthokeratology Treatment.

To compare tear film osmolarity (TFO) measurements in non-contact lens (CL) wearers and wearers of hydrogel or overnight orthokeratology (OK) CLs, and to assess possible effects of long-term OK on TFO. Overall, 108 subjects with moderate myopia participated in 2 experiments, and TFO was measured using the TearLab osmolarity system. In experiment 1, TFO measurements were made in 77 right eyes of 23 non-CL wearers, 26 hydrogel wearers, and 28 OK wearers. Subjects in the last 2 groups had worn their CL for at least 3 years. In experiment 2, 31 individuals (habitual soft CL wearers) were enrolled for prospective long-term follow-up of OK treatment. These subjects were fitted with Paragon-CRT (n=16) or Seefree (n=15) lenses, and TFO readings were taken at baseline and after 1 month and 1 year of lens wear and after 1 month of OK treatment interruption. Values of TFO were within the normal limits in all 3 subject groups, although significantly lower osmolarities (P<0.01) were observed in non-CL wearers (281.7±5.9 mOsm/L) compared with hydrogel (291±16.5 mOsm/L) or OK lens wearers (301.7±10.8 mOsm/L). In experiment 2, TFO differed significantly at baseline between the Paragon-CRT and Seefree groups (P<0.05), and a significant decrease in TFO compared with baseline (P<0.01) was observed in the Paragon-CRT group after 1 month of cessation of lens wear. Higher TFO values were observed in lens wearers (hydrogel or OK) than non-CL wearers. After interruption of OK treatment, TFO returned to similar values to those found in non-CL wearers.

Corneal confocal microscopy assessment in contact lens discomfort

PurposeThe aim of this study was to analyze whether symptoms of discomfort in CL wearers were associated to changes in the nerve morphology and/or the density of dendritic cells in the corneal sub‐basal nerve plexus.MethodsSixty subjects were included: 20 symptomatic CL wearers (SCLW), 20 asymptomatic CL wearers (ACLW), and 20 non wearers (NCLW). Ocular Surface Disease Index (OSDI), visual acuity, tear osmolarity, biomicroscopy findings, tear film break‐up time, corneal and conjunctival staining, Schirmer test, and confocal microscopy were performed. In the confocal images number and density of nerves, density of nerve branches, grade of nerve tortuosity, and density of dendritic cells were analyzed.ResultsOSDI and lid roughness was higher in the SCLW group (p=0.S009 and p=0.04, respectively), limbal hyperaemia was raised in the ACLW group (p=0.S009), and tear osmolarity was increased in both CL wearers groups (p=0.000), in comparison with the NCLW group. Subjects were divided into low and high density of dendritic cells using a 75 cells/mm2 cut‐off. This distribution was significantly different (p=0.04) between the CL wearers (21 and 19 subjects had low and high cell density, respectively) and the NCLW group (16 and 4, respectively). The CL type was significantly different (p=0.011) between CL wearers with low (4 and 17 subjects wear conventional and silicone hydrogel CLs, respectively) and high (11 and 8, respectively) cell density.ConclusionsSymptoms of discomfort in CL wearers seem not to be related to changes in the nerve morphology or density of dendritic cells in the corneal sub‐basal nerve plexus.

Photon correlation spectroscopy applied to tear analysis

This study aims to deepen the knowledge on tear film properties by the development of a protocol for analyses of Photon Correlation Spectroscopy (PCS) on human tears and by the comparison between PCS results obtained on tears of contact lens wearers and non-wearers. Tears (5μL) were collected by a glass capillary. The analyses provide the hydrodynamic diameter of tear components by analyzing intensity fluctuations in time of scattered light. PCS appears a promising technique for studying tear features and for shedding light on specific eye conditions, such as on the clinical effects of CL wear. In fact, statistical difference (p<0.001) was found between the measured mean hydrodynamic diameter of tear components of wearers and non-wearers, the resulting value significantly higher for CL wearers. The scenario does not substantially change after (25±5)min from the CL removal. The difference is attributed to changes in the interactions between tear constituents due to CL wear. In order to get deeper insights on the influence of CL wear on aggregation and structure of tear components, a preliminary Electron Spin Resonance (ESR) investigation was performed, monitoring Fe3+ species. ESR spectra on tears of both CL wearers and non-wearers showed the presence of intense signals, probably associated to iron (III) centers in proteins such as lactoferrin, and a weaker resonance attributable to Fe3+ species interacting with S–S bridges of lysozyme. Differences in ESR spectra between CL wearers and non-wearers were detected and tentatively ascribed to changes in coordination or in local environment of Fe3+ centers connected to aggregation phenomena induced by CL wear, which promote their interaction with other neighboring iron species.

The influence of soft contact lens materials on the central, para-central and peripheral corneal endothelium

PURPOSE: To examine the influence of a variety of soft contact lens (SCL) materials on the corneal endothelium, prior to and following two weeks cessation of SCL wear. METHODS: Corneal endothelial cells were examined using a CEM-530 specular microscope (Nidek, Japan). Full-time SCL wearers (n = 31 eyes) were compared to a non-contact lens (NCL) control group (n = 28 eyes) of a similar age (SCL: 20.82 ± 1.69 years, NCL: 21.14 ± 2.85 years, p = 0.58). Parameters analysed were endothelial cell density (ECD; cell/mm2), mean cell area (MCA; μ2), coefficient of variation (COV) and hexagonality (%). RESULTS: Prior to SCL cessation, two-way ANOVA testing showed significant differences between silicone hydrogel (SiH) SCL materials for the COV at 0o, with generation 2 SiH (G2SiH) wearers showing increased COV (27.67 ± 3.78) compared to generation 3 SiH (G3SiH) wearers (24.50 ± 3.73, p = 0.01). COV at the superior periphery was significantly lower in the NCL group (25.63 ± 2.79) compared to the hydrogel group (29.92 ± 6.22, p = 0.02). The MCA in the inferior periphery was also significantly higher in the NCL group (346.92 ± 36.75) compared to the hydrogel group (314.92 ± 16.57, p = 0.02). Following 14 days SCL cessation, no statistically significant differences in stability of endothelial parameters were detected between NCL and SCL material groups (all p values >0.05). CONCLUSION: SCL wear has an effect on paracentral and peripheral corneal endothelial measurements in SCL wearers compared to NCL wearers; with largest significant differences seen between NCL and hydrogel SCL wearers. Following two weeks SCL cessation, there were no significant differences in the stability of all endothelial measurements, regardless of which SCL material was worn. BACKGROUND Aoife Lloyd McKernan BSc (Hons) Optom FAOI1 , Luisa Simo Mannion DOO EU PhD2 , Veronica O'Dwyer DipOpt FAOI PhD 1 1Dublin Institute of Technology, Ireland, 2Plymouth University, United Kingdom Corneal hypoxia due to over-wear of low oxygen transmissibility (DK/t) SCLs results in endothelial polymegathism and corneal thinning 1. High DK/t SiH materials are reported to have negligible effects on the corneal endothelium 2. Hypothesis: endothelial parameters would show greater variation in a full-time low DK/t hydrogel SCL wearing group compared to a high DK/t SiH wearing group or NCL control group. Refitting previous low DK/t CL wearers with higher DK/t CLs results in reversal of hypoxia-induced endothelial changes 2. It is proposed that this reversal is linked to both the resolution of hypoxia and due to a mechanical reorganisation of the corneal endothelium following resolution of oedema-induced increased corneal thickness2. The stability of endothelial parameters in this study was examined over a two week period following cessation of SCL wear. This time period was chosen as it is the recommended SCL cessation time prior to corneal refractive surgery 3 and it has been previously demonstrated4 that the resolution of corneal and curvature and thickness following SCL cessation occurs within this time. Hypothesis: it was expected that endothelial corneal parameters in full time hydrogel SCL wearers would be more unstable after two weeks SCL wear cessation than SiH SCL wearers or NCL wearers METHODS  Inclusion criteria • Myopic prescriptions with low astigmatism ( 5 days per week for at least one year). • NCL group: no history of CL wear in the year prior

The influence of the refractive correction on the vision-related quality of life in keratoconus patients.

The aim of this study was to assess the impact of refractive correction [spectacles vs rigid gas-permeable contact lenses (RGP CLs)] on the vision-related quality of life (VR-QoL) obtained with the standardized questionnaire, NEI-VFQ-25, in keratoconus patients compared with healthy myopic subjects. The Spanish version of NEI-VFQ-25 was administered two consecutive times to 25 keratoconus patients (RGP CL wearers) and 25 healthy myopic subjects (RGP and soft CL wearers). The first time was to assess the VR-QoL for spectacle wearing, such as those for refractive correction, and the second time was for CL wearing. Keratoconus patients showed a lower VR-QoL impairment (P < 0.01) than healthy subjects in the total and all subscale score of NEI-VFQ-25 related to wearing spectacles. With CL correction, keratoconus patients showed a VR-QoL improvement with statistically significant differences (P < 0.04) in only four subscales, including distance activities, mental health, color vision and peripheral vision, compared with healthy subjects. In the keratoconus group, compared to spectacle use, CL wear improved the VR-QoL score (P = 0.01) and all subscales except for ocular pain (P < 0.01) and mental health (P = 0.25). The use of the NEI-VFQ-25 to explore the difference in the VR-QoL between healthy subjects and patients with keratoconus provides further evidence of improved VR-QoL with RGP CL wear compared with spectacles in keratoconus patients. RGP CL management in keratoconus patients could minimize the impact of the disease on the patient's well-being.

Relationships among Tear Film Stability, Osmolarity, and Dryness Symptoms.

To examine the relationships among tear osmolarity, tear film stability, and several measures of dry eye (DE) symptoms in a multivariable analysis. A cross-sectional study was conducted with 137 subjects (68 non-contact lens [CL] wearers and 69 soft CL wearers) recruited from a university campus. Tear breakup time (TBUT) was measured noninvasively (NITBUT) and with fluorescein (FTBUT). Tear osmolarity was measured by an osmometer. Dry eye symptoms were assessed using the Dry Eye Flow Chart and several different questionnaires. Subjects ranged in age from 18 to 67 years, with a mean of 28 years. Subjects had a mean (SD) osmolarity of 293 (10) mOsm/L, NITBUT of 14.1 (10.9) seconds, and FTBUT of 14.8 (12.6) seconds. Shorter NITBUT and FTBUT were significantly associated with female sex (p = 0.001 and p = 0.027, respectively) and Asian ethnicity (p = 0.030 and p = 0.004, respectively). There were no clinically significant relationships between tear osmolarity and FTBUT, NITBUT, or DE symptoms. Higher Dry Eye Flow Chart score (i.e., worse symptoms) was associated with older age (p < 0.001), female sex (p = 0.014), CL wear (p < 0.001), shorter NITBUT (p < 0.001), and shorter FTBUT (p = 0.028). The sensitivities and specificities for using clinical measurements to diagnose moderate to severe DE were as follows: osmolarity, 0.67 and 0.46, respectively; NITBUT, 0.72 and 0.52, respectively; and FTBUT, 0.68 and 0.57, respectively. In a population of asymptomatic, mild and moderate DE patients, increased tear osmolarity was not significantly associated with reported symptom severity and frequency. Tear osmolarity, NITBUT, and FTBUT exhibited similar sensitivities and specificities when used to diagnose moderate to severe DE.

European survey of contact lens wearers and eye care professionals on satisfaction with a new water gradient daily disposable contact lens

European survey of contact lens wearers and eye care professionals on satisfaction with a new water gradient daily disposable contact lens Inma P&eacute;rez-G&oacute;mez,1 Tim Giles2 1Alcon Management SA, Geneva, Switzerland; 2Alcon Laboratories, Inc., Fort Worth, TX, USA Background: Delefilcon A daily disposable water gradient contact lenses (CLs; DAILIES TOTAL1&reg;) have radically different properties at the lens surface when compared with the core, resulting in high oxygen transmissibility with a lubricious surface. Purpose: To assess the real-world success of delefilcon A daily disposable CLs using a European survey, and to determine whether a successful experience changes eye care professionals&#39; (ECPs) CL preference or anticipated recommendation patterns. Methods: Current soft CL wearers, aged &ge;18 years, were eligible for participation. Baseline demographics and 2-week data were obtained by ECPs after fitting &ge;5 to &le;10 participants with delefilcon A CLs. Results: Twenty-four ECPs from 16 European countries assessed the use of delefilcon A CLs in 280 participants. Nearly two-thirds (62.9%; number [n]=176) of the participants reported dryness and/or discomfort with their habitual CLs. There was a 78.9% reduction in the proportion of participants with end-of-day dryness after 2 weeks of using delefilcon A CLs (P&lt;0.0001). More participants agreed that they could wear their CLs comfortably all day long with delefilcon A CLs (93.2%; n=261) versus habitual CLs (58.2%; n=163; P&lt;0.0001). There was a strong preference for delefilcon A CLs when compared with habitual lenses worn, with 81.8% of participants agreeing with the statement &quot;I prefer these lenses to my previous contact lenses.&quot; Delefilcon A CLs were also highly rated by ECPs following their experience with fitting the lens. All (100%) ECPs agreed or strongly agreed that the perceived comfort with delefilcon A CLs is better than that with other daily disposable lenses and that they would recommend these lenses to colleagues. Conclusion: The results indicate that delefilcon A daily disposable water gradient CLs may offer wearers greater comfort than their habitual CLs. Keywords: water gradient contact lens, delefilcon A, comfort, silicone hydrogel, daily disposable

KEYNOTE ADDRESS: Understanding the business of contact lenses

KEYNOTE ADDRESS: Understanding the business of contact lenses

Risk factors for contact lenses related microbial keratitis: a prospective multicenter case control study

AbstractPurpose MMK remains a rare complication of CL wear, but is of interest because it is both a major cause of new cases of MK in the population, and the only sight‐threatening complication of an otherwise safe method of vision correction. The aim of the study is to identify risk factors and to put into perspective the individual risk and the societal burden of CL‐related MK patients.Methods A prospective multicenter case‐control study was conducted in 16 French University Hospitals on all lenses wearers presenting with MK between July 2007 and December 2011. Patients had a complete ophthalmological examination and were interviewed by a 50 items anonymous "questionnaire" to determine subject demographics and lenses wear history. The CL related MK subpopulation (Case) was compared to healthy CL wearers (Control).Results 684 CL related MK and 599 healthy CL wearers were included. Patients wearing soft contact lenses had a higher risk for MK, as compared as rigid lenses wearers (Relative risk, 4.1 ; p &lt; 0.001). Among soft lenses, daily disposable CL (RR, 1.8 ; p = 0.01) and 2 weekly replacement CL (RR, 2.1 ; p &lt; 0.001) had an increased risk of MK than monthly replacement CL, respectively because of some lacks in basic rules of hygiene (absence of hand washing) and the absence of a professional supervision for daily disposable CL and the overtaking of the deadline of renewal for 2 weekly replacement CL.Conclusion With the increasing avaibility of CL, notably through internet or local market, this study serves to highlight the increasingly documented dangers of freely available CL without professional supervision and of the lack of information about the basic rules of hygiene and the basis of CL care and handling.

Estimating the Annual Economic Burden of Illness Caused by Contact Lens–Associated Corneal Infiltrative Events in the United States

The aim of this study was to estimate the annual cost of illness caused by contact lens-associated corneal infiltrative events (CL-CIEs) among soft CL wearers in the United States. This study was conducted in the United States. The study population was comprised of daily wear contact lens users in the United States, which number approximately 35 million. A comprehensive review of the medical literature for data on the annual incidence of CL-CIEs was conducted. Cost estimates were drawn from the literature and published tariffs. The perspective of the study was a U.S. healthcare perspective and because of the short duration of most CL-CIEs, no discounting was performed. The main outcome measure involved the total annual number of persons with CL-CIEs and associated direct and indirect costs. In the United States in 2010, it was calculated that a total of 32,031 nonsevere and 17,248 severe CL-CIEs occurred, respectively. The cost per nonsevere and severe CL-CIEs was estimated to be $1,002.90 and $1,496.00, respectively. Overall, the total estimated direct and indirect cost of nonsevere CL-CIEs and severe CL-CIEs in the United States in 2010 was estimated to be $58 million. This study estimated the economic burden of illness imposed by CL-CIEs on both the healthcare system and individual patients in the United States. Strategies designed to minimize the occurrence and impact of CL-CIEs, such as using improved lens care regimens and lens case management, the use of daily disposable lenses, and more efficacious ocular antibiotics may be beneficial in reducing this economic burden.