Robin L. Chalmers

Characterization of ocular surface symptoms from optometric practices in North America.

Purpose. This study characterized ocular symptoms typical of dry eye in an unselected optometric clinical population in the United States and Canada. Methods. Self-administered dry eye questionnaires, one for non–contact lens wearers (dry eye questionnaire) and one for contact lens wearers (contact lens dry eye questionnaire), were completed at six clinical sites in North America. Both questionnaires included categoric scales to measure the prevalence, frequency, diurnal severity, and intrusiveness of nine ocular surface symptoms. The questionnaires also asked how much these ocular symptoms affected daily activities and contained questions about computer use, medications, and allergies. The examining doctors, who were masked to questionnaire responses, recorded a nondirected dry eye diagnosis for each patient, based on their own diagnostic criteria. Results. The dry eye questionnaires were completed by 1,054 patients. The most common ocular symptom was discomfort, with 64% of non–contact lens wearers and 79% of contact lens wearers reporting the symptom at least infrequently. There was a diurnal increase in the intensity of many symptoms, with symptoms such as discomfort, dryness, and visual changes reported to be more intense in the evening. The 22% percent of non–contact lens wearers and 15% of contact lens wearers diagnosed with dry eye (most in the mild to moderate categories) reported symptoms at a greater frequency than those not diagnosed with dry eye. Conclusions. Our results show that symptoms of ocular irritation and visual disturbances were relatively common in this unselected clinical population. The intensity of many ocular symptoms increased late in the day, which suggested that environmental factors played a role in the etiology of the symptoms.

Responses of contact lens wearers to a dry eye survey

The purpose of this study was to examine ocular symptoms that have been associated with dry eye among contact lens wearers. A dry eye questionnaire was administered at random to 83 contact lens wearers at a private practice in Toronto, Ontario. On average, the most frequent ocular symptom among those queried was dryness and the least frequent was soreness. There was a significant shift (p < 0.0001; paired t-test) toward increased symptoms in the evening compared with the morning. Blurry, changeable vision was also a frequent and noticeable symptom. However, most subjects reported that their ocular symptoms were not severe enough for them to stop work or hobbies or to remove their contact lenses. Our results show that the symptoms of ocular dryness and discomfort are relatively common among contact lens wearers, and that they worsen toward the end of the day. These findings suggest that lens care practitioners should examine their patients who wear contact lenses toward the end of the day to best identify symptomatic patients.

Vascular response to extended wear of hydrogel lenses with high and low oxygen permeability

Purpose. The purpose of this study was to determine the impact of extended wear of high and low oxygen permeability (Dk) lenses on the development or resolution of limbal hyperemia and corneal neovascularization in a randomized prospective clinical trial. Methods. Adapted daily-wear contact lens wearers were randomly assigned to one of two groups. The low-Dk group (N = 23) wore etafilcon A lenses (Dk/t = 40) for up to 7 days and 6 nights, and the high-Dk group (N = 39) wore lotrafilcon A lenses (Dk/t = 175) for up to 30 days and nights. Limbal hyperemia and neovascularization were assessed and graded during 9 months of extended wear. A stratified analysis to determine how change in ocular redness depended on initial presentation was also conducted. Results. On a 0 to 100 scale, extended wear of low-Dk lenses resulted in a 16-point increase in limbal hyperemia (p < 0.0001); no significant change occurred with the high-Dk lenses. The difference was greatest for low-Dk participants who initially presented with lower levels of hyperemia (N = 18). There was a slight resolution of redness in participants who initially presented with higher levels of hyperemia (N = 10) after wearing the high-Dk lenses. Neovascularization increased by an average of 0.5 on a scale of 0 to 4 in low-Dk lens wearers (p < 0.0001) but remained unchanged in the high-Dk lens wearers. The increase was most marked for the low-Dk group with lower levels of neovascularization at baseline. Conclusions. Subjects who wore lenses with higher oxygen permeability for 9 months of extended wear exhibited a lower vascular response of the ocular surface compared with subjects who wore lenses of lower oxygen permeability for the same period. This result was found both for the surface limbal vessels and in the deeper neovascular stromal vessels. Moderate neovascularization also developed after 3 months of extended wear of low-Dk hydrogels, whereas high-Dk lenses caused no neovascularization.

Prevalence of Ocular Surface Symptoms, Signs, and Uncomfortable Hours of Wear in Contact Lens Wearers: The Effect of Refitting with Daily-Wear Silicone Hydrogel Lenses (Senofilcon A)

Purpose. Many soft contact lens wearers have symptoms or signs that compromise successful lens wear. This study estimated the prevalence of problems in current wearers of soft contact lenses and tested the effect of refitting patients with senofilcon A silicone hydrogel lenses (ACUVUE Oasys). Methods. Prevalence was estimated from 1,092 current lens wearers for frequent or constant discomfort or dryness, at least 2 hours of uncomfortable wear, at least grade 2 limbal or bulbar hyperemia (0–4), or at least grade 3 corneal staining (0–15). In the second part of the study, 112 of the 564 wearers classified as problem patients were refitted with senofilcon A lenses and reassessed 2 weeks later. Results. Fifty-two percent (564 of 1,092) had some qualifying criteria, with dryness reported by 23%, discomfort by 13%, and at least 2 hours of uncomfortable wear by 27%. Six percent of subjects had qualifying limbal hyperemia; 10% had bulbar hyperemia; and 12% had corneal staining. After refitting 112 problem patients, 75% had less dryness; 88% had better comfort (P<0.0001 each); and 76% had fewer uncomfortable hours of wear (P=0.004). Although the average wearing time was unchanged, comfortable wearing time increased significantly (10.4 to 11.6 hours) (P=0.004). All (35 of 35) eyes with qualifying limbal hyperemia before the refit also improved (P<0.0001), as did 80% (40 of 50) of those with bulbar hyperemia (P<0.0001) and 76% (26 of 34) of those with corneal staining (P=0.005). Conclusions. Most soft lens wearers encounter clinically significant signs or symptoms with their current contact lenses. Refitting with new-generation silicone hydrogel lenses (senofilcon A) can alleviate some of these common problems.

Validation of the 5-Item Dry Eye Questionnaire (DEQ-5): Discrimination across self-assessed severity and aqueous tear deficient dry eye diagnoses

PURPOSE To validate a subset of Dry Eye Questionnaire (DEQ) items that discriminate across self-assessed severity and various diagnoses of dry eye (DE). METHODS Subjects (n=260) in 2 studies received a clinical DE diagnosis, completed the 6-page DEQ and self-assessment of DE severity (SA-Sev). SA-Sev ratings were: 46 Severe, 107 Moderate, 77 Mild, and 46 None. Dry eye diagnoses were: 48 asymptomatic controls (C), 155 non-SS KCS, and 57 Sjögren Syndrome (SS). All DEQ items were correlated to SA-Sev by Spearman. Groups of highly correlated DEQ items were tested to discriminate SA-Sev; and the subset tested to distinguish across DE diagnosis. RESULTS The DEQ-5 comprises: frequency of watery eyes (r=0.48), discomfort (r=0.41), and dryness (r=0.35), and late day (PM) intensity of discomfort and dryness (r=0.42, 0.36) all significantly correlated to SA-Sev (p<0.01). Mean DEQ-5 scores by SA-Sev: Severe 14.9+/-2.3, Moderate 11.4+/-3.3, Mild 8.6+/-3.1 and None 2.7+/-3.2 (ANOVA, p<0.0001) and by DE diagnosis: C 2.7+/-2.9, non-SS KCS10.5+/-4.5 and SS14.0+/-3.4, differing significantly overall (Z=-8.6, p=0.000) and between diagnoses (X(2)=116.3, p=0.000). Watery eyes were reported primarily by non-SS KCS. Proposed screening criteria for the DEQ-5 are >6 for DE and >12 for suspected SS. CONCLUSIONS The DEQ-5, the sum of scores for frequency and PM intensity of dryness and discomfort plus frequency of watery eyes, effectively discriminated across self-assessed severity ratings and between patients with DE diagnoses. These results indicate that DEQ-5 scores >6 suggest DE and scores >12 may indicate further testing to rule out SS-DE.

TFOS DEWS II Diagnostic Methodology report

The role of the Tear Film and Ocular Surface Society (TFOS) Dry Eye Workshop (DEWS) II Diagnostic Methodology Subcommittee was 1) to identify tests used to diagnose and monitor dry eye disease (DED), 2) to identify those most appropriate to fulfil the definition of DED and its sub-classifications, 3) to propose the most appropriate order and technique to conduct these tests in a clinical setting, and 4) to provide a differential diagnosis for DED and distinguish conditions where DED is a comorbidity. Prior to diagnosis, it is important to exclude conditions that can mimic DED with the aid of triaging questions. Symptom screening with the DEQ-5 or OSDI confirms that a patient might have DED and triggers the conduct of diagnostic tests of (ideally non-invasive) breakup time, osmolarity and ocular surface staining with fluorescein and lissamine green (observing the cornea, conjunctiva and eyelid margin). Meibomian gland dysfunction, lipid thickness/dynamics and tear volume assessment and their severity allow sub-classification of DED (as predominantly evaporative or aqueous deficient) which informs the management of DED. Videos of these diagnostic and sub-classification techniques are available on the TFOS website. It is envisaged that the identification of the key tests to diagnose and monitor DED and its sub-classifications will inform future epidemiological studies and management clinical trials, improving comparability, and enabling identification of the sub-classification of DED in which different management strategies are most efficacious.

Age and Other Risk Factors for Corneal Infiltrative and Inflammatory Events in Young Soft Contact Lens Wearers from the Contact Lens Assessment in Youth (CLAY) Study

PURPOSE To describe age and other risk factors for corneal infiltrative and inflammatory events (CIEs) in young, soft contact lens (SCL) wearers and to model the age-related risk. METHODS A multicenter, retrospective chart review of 3549 SCL wearers (8-33 years at first observed visit, +8.00 to -12.00D, oversampling <18 years) captured CIEs from January 2006 to September 2009. The review noted age, sex, SCL worn, use of lens care products, and SCL wearing history. Event diagnoses were adjudicated to consensus by reviewers masked to wearer identity, age, and SCL parameters. Significant univariate risk factors for CIEs were subsequently tested in multivariate generalized estimating equations. RESULTS Charts from 14,305 visits observing 4,663 SCL years yielded 187 CIEs in 168 wearers. Age was a significant nonlinear risk factor, peaking between 15 and 25 years (P < 0.008). Less than 1 year of SCL use was protective versus longer years of wear (P < 0.0003). Use of multipurpose care products (2.86×), silicone hydrogels (1.85×), and extended wear (2.37×) were significantly associated with CIEs in the multivariate model (P < 0.0001 each). CONCLUSIONS Patient age, years of lens wear, use of multipurpose care products, silicone hydrogels, and extended wear were all significantly associated with CIEs with SCL wear. Use of SCLs in young patients aged 8 to 15 years was associated with a lower risk of infiltrative events compared with teens and young adults. In terms of safety outcomes, SCLs appear to be an acceptable method of delivering optics designed to manage myopia progression in children and young teens in the future.

Tear breakup dynamics: a technique for quantifying tear film instability.

Purpose. The purpose of this study was to develop a novel, quantitative measurement of tear film breakup dynamics (TBUD) to study the phenomenon of tear breakup in dry eye and control subjects and its impact on dry eye symptoms. Methods. Ten control and 10 dry eye subjects completed the Dry Eye (DEQ) and other questionnaires. After the instillation of sodium fluorescein, subjects kept the tested eye open for as long as possible, similar to a staring contest, while tear film breakup was videotaped (S-TBUD). The maximum blink interval (MBI) and tear breakup time (TBUT) were measured from digital movies by a masked observer. Individual frames of movies were converted to gray-scale images, maps of relative tear film fluorescence were generated, and the total area of tear breakup (AB) of the exposed cornea was quantified. Results. On average, dry eye subjects demonstrated a higher AB and shorter TBUT and MBI, but only the AB was significantly different (p = 0.023). Subjects most often used the descriptors stinging and burning to describe their sensations during staring trials. The AB showed a high correlation between eyes and with some DEQ symptom measures. Conclusions. These methods allow objective quantification and tracking of the phenomenon of tear breakup. Our results suggest that tear breakup stresses the corneal surface, resulting in stimulation of underlying nociceptors. The tear film of dry eye subjects was less stable than controls. They had a larger AB measured from the last video frame before MBI (i.e., just before blinking) than did controls. This perhaps reflects adaptation to the repeated stress of tear instability in dry eye.

Temporal progression and spatial repeatability of tear breakup

Purpose. This study used image analysis to compare the temporal progression and spatial reoccurrence of the area of tear film breakup (AB) in dry eye and normal subjects. Methods. Tear breakup was induced in 10 control and 10 dry eye subjects during the Staring Tear Breakup Dynamics (S-TBUD) test, which involves keeping one eye open for as long as possible, termed the maximum blink interval (MBI). Video imaging of tear film fluorescence measured the onset and progression of the AB. AB location and area were mapped. The progression of ABs from the first trial, the rate of tear breakup or dry area growth rate (DAGR), and the overlap of ABs in three successive trials 5 minutes apart were computed by custom MATLAB programs. Results. The final AB before the blink was significantly greater (average, 30.7% ± 12.5% vs. 16.1% ± 9.2%) and the MBI was significantly less (average, 19.5 ± 9.0 seconds vs. 56.5 ± 38.9 seconds) among dry eye subjects compared with controls (p < 0.05, Mann-Whitney U test). The DAGR was four times greater among dry eye subjects, who also showed significantly more tear breakup in the central cornea than controls (p < 0.0001, Mann-Whitney U test). When the final image from three successive trials was overlapped, tear breakup occurred more often in the same location in three trials than would be expected by the overlap of independent points. Conclusions. Structural influences such as the “black line” or corneal lid defects appeared to influence the recurrence of breakup in the same region. The S-TBUD quantitative image analysis technique demonstrates that the tear film of subjects with dry eye continues to rapidly destabilize after an initial first break; thus, a low TBUT was combined with a high DAGR. The central corneal region of subjects with dry eye appeared especially susceptible to increased tear breakup when compared with controls.

Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) and opinion of contact lens performance.

Purpose. To report on the development and validation of a short form of the Contact Lens Dry Eye Questionnaire (the CLDEQ-8) to enable it to reflect status of and change in overall opinion (“opinion”) of soft contact lenses (SCLs). Methods. Item reduction for the CLDEQ was achieved by correlation with overall opinion of SCLs at follow-up visits in a sample of 38 SCL wearers at one academic clinical site. The CLDEQ-8 score (frequency plus late day intensity of dryness, discomfort, and “blurry vision”; frequency of “closing eyes to rest them” and “removing CLs to relieve discomfort”) was then tested in 379 SCL wearers in a multicenter study with analysis stratified by opinion ratings at baseline and 2 weeks postrandomization to new silicone hydrogel SCLs. The sum of CLDEQ-8 scores (maximum 37) was correlated with opinion by Spearmans rank correlation coefficient and analyzed for change in opinion by analysis of variance (ANOVA). Results. The CLDEQ-8 scores in the validation sample were highly correlated with habitual baseline opinion (−0.44, p < 0.0001) and responsive to change in opinion postrandomization (−0.58, p < 0.0001). Baseline CLDEQ-8 scores by opinion status were as follows: Fair: 17.4 ± 8.7, Good 13.7 ± 6.4, Very Good 9.1 ± 4.7, and Excellent 6.4 ± 3.7 (ANOVA, F = 291.1, p < 0.0001). After 2 weeks, change in CLDEQ-8 scores by improvement status was as follows: Much Improved: −16.7 ± 10.0, Unchanged: −2.3 ± 5.0, to Much Worse +8.5 ± 5.8 (ANOVA, F = 16.5, p < 0.001). Conclusions. The CLDEQ-8 score significantly reflected baseline status and change in overall opinion after refitting with two types of silicone hydrogels. The CLDEQ-8 score is a valid outcome measure in SCL clinical trials to reflect opinion of SCLs.