Contact Lens & Anterior Eye

Editorial Board

2010-04-01

The new role for eye care practitioners in management of dry eye—with and without contact lenses

Robin L. Chalmers, Michel Guillon — 2010-04-01

Twenty-four years ago, BCLA Gold Medal honoree Professor Charles McMonnies, first published a paper on the use of questionnaires to measure and classify patients’ dry eye symptoms . A year later, in 1987, his team deepened that effort by publishing the questions for screening dry eye patients as well . They found that 5% of patients may have been in need of further diagnostic workup for dry eye. If this issue has been researched for so many years, why is the British Contact Lens Association dedicating this special issue to clinical research aspects of dry eye in 2010? The fact remains that the clinical conundrum of determining effective, easy-to-use treatments for dry eye remains an innovating, complex area in clinical research and practice alike and remains worthy of our attention.

Essential fatty acids for dry eye: A review

Marco Roncone, Hannah Bartlett, Frank Eperjesi — 2009-12-25

Abstract: Purpose: Dry eye is a common complaint often encountered in optometric practice. However, it is a difficult condition to treat as clinical signs do not always correlate with patient symptoms. Essential fatty acids (EFA), particularly omega-3 EFA, may be effective in dealing with the underlying causes.Methods: A literature review was carried out on the PubMed, ScienceDirect and Ovid databases. Searches included keywords such as ‘dry eye’, ‘essential fatty acids’ and ‘nutrition’ to find articles relating to the treatment of dry eye syndrome (DES) with omega-3 EFAs.Results: Omega-3 and -6 EFAs need to be consumed together within a reasonable ratio to be effective. Currently, typical diets in developed countries lack omega-3 EFA and this results in an overexposure to omega-6. Omega-3 supplementation has an anti-inflammatory effect, inhibiting creation of omega-6 prostaglandin precursors. Omega-3 EFAs also demonstrate anti-inflammatory action in the lacrimal gland preventing apoptosis of the secretory epithelial cells. Supplementation clears meibomitis, allowing a thinner, more elastic lipid layer to protect the tear film and cornea.Conclusion: Dietary supplementation of omega-3 EFA has already proven to be effective in coronary heart disease and arthritis. Safety is not a concern as it works synergistically with omega-6 in the body. Evidence suggests that supplementation with omega-3 EFA may be beneficial in the treatment and prevention of DES.

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

Robin L. Chalmers, Carolyn G. Begley, Barbara Caffery — 2010-01-22

Abstract: 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 (X2=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.

Tear osmolarity measurement using the TearLab™ Osmolarity System in the assessment of dry eye treatment effectiveness

Umberto Benelli, Marco Nardi, Chiara Posarelli, Timothy G. Albert — 2010-02-15

Abstract: Purpose: To evaluate the efficacy of three commercially available lubricant eye drops for the treatment of mild, dry, irritated eyes.Methods: Randomized, investigator-masked evaluation of 60 patients in which 20 patients used carboxymethylcellulose sodium (CMC), 0.5% (Cellufresh®, Allergan Inc., Irvine, CA) (group 1); 20 patients used a drop containing polyethylene glycol 400, 2.5% and sodium hyaluronate (Blink® Intensive Tears, Abbott Medical Optics Inc., Santa Ana, CA) (group 2); and 20 patients used HP Guar 0.18% (Systane®, Alcon Laboratories Inc., Ft. Worth, TX) (group 3). Study visits were at baseline and 1 month. Tests performed at both visits included Schirmer, tear-film break-up time (TBUT), visual acuity, fluorescein staining, tear osmolarity and wavefront aberrometry. Osmolarity testing was performed prior to instillation of the lubricant eye drops and then a final time 5min after instillation of the drop at both day 1 and day 30. Tear osmolarity was performed only in the right eye and only one time before and after instillation of lubricant eye drops.Results: At day 1 the mean reduction in osmolarity 5min after instillation of the lubricant eye drop was, −5.0±1.9 in group 1, −9.0±4.2 in group 2 and −5.0±2.2 in group 3. At day 30 the mean reduction in osmolarity 5min after instillation of the lubricant eye drop was, −5.6±2.3mOsm/L in group 1; −9.9±2.8mOsm/L in group 2 and −4.5±1.8mOsm/L in group 3. The differences were statistically significant between groups 1 and 2, and 2 and 3. There was a reduction of osmolarity from day 1 to day 30 but the differences were not statistically significant. We feel that after a 30-day treatment with the lubricant eye drops, the lower osmolarity values could indicate that the tear film is progressing towards a more normal osmolarity value. A future study could examine the tear osmolarity value after 60 or 90 days of usage. LogMAR best-corrected visual acuity (BCVA) results showed an improvement in group 2 compared with baseline with no change in BCVA in groups 1 and 3. There was no statistically significant change from day 1 to 1 month in TBUT, while the Schirmer test showed an improvement in all groups at 1 month.Conclusions: Assessment of tear osmolarity provides the most objective, measurable test for determining improvement in dry eye patients. The instillation of any artificial tear or lubricant eye drop should decrease the tear-film osmolarity. The results found that polyethylene glycol 400, 0.25% and sodium hyaluronate (Blink® Intensive Tears) significantly improved tear osmolarity compared with carboxymethylcellulose sodium (CMC), 0.5% (Cellufresh®) and HP Guar 0.18% (Systane®) after instillation.

Role of hypo-osmotic saline drops in ocular comfort during contact lens wear

Ulrike Stahl, Mark Willcox, Fiona Stapleton — 2010-02-01

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

Effect of castor oil emulsion eyedrops on tear film composition and stability

Cécile Maïssa, Michel Guillon, Peter Simmons, Joseph Vehige — 2009-12-07

Abstract: Purpose: An emulsion eyedrop containing castor oil has been shown to modify the tear film lipid layer and increase tear film stability. The primary objectives of this investigation were to measure the prevalence of castor oil in the tear fluid over time and quantify the effects on the lipid layer. A secondary objective was to quantify the initial effects on ocular symptomatology.Methods: The investigation was an open label pilot study on 5 normal and 10 dry eye subjects. A single eyedrop (Castor oil emulsion, Allergan) was instilled in each eye; the tear film appearance and composition were monitored for 4h via in vivo visualisation using the Tearscope™ and post in vivo tear samples analysis by HPLC.Results: Combined results for both normal and dry eye subjects showed that castor oil was detected up to 4h after a single eyedrop instillation and associated with an increase in the level of tear film lipid. The relative amount of various lipid families was also changed. An increase in tear lipid layer thickness was significant up to one hour post-instillation for the symptomatic sub-population. The changes in tear film characteristics were associated with significantly lower symptoms up to four hours post-instillation for the symptomatic sub-population.Conclusion: This pilot investigation showed that castor oil eyedrops achieved a residence time of at least four hours post-instillation, producing a more stable tear film and an associated significant decrease in ocular symptoms over the entire follow-up period for the symptomatic subjects.

Effect of a liposomal spray on the pre-ocular tear film

Jennifer P. Craig, Christine Purslow, Paul J. Murphy, James S.W. Wolffsohn — 2010-01-22

Abstract: Purpose: With the potential to address evaporative dry eye, a novel spray has been developed in which phospholipid liposomes are delivered to the tear film via the surface of the closed eyelid. This study evaluated the short-term effects of liposomal spray application on the lipid and stability characteristics of the pre-ocular tear film in normal eyes.Methods: Twenty-two subjects (12M, 10F) aged 35.1±7.1 years participated in this prospective, randomised, double-masked investigation in which the liposomal spray was applied to one eye, and an equal volume of saline spray (control) applied to the contralateral eye. Lipid layer grade (LLG), non-invasive tear film stability (NIBUT) and tear meniscus height (TMH) were evaluated at baseline, and at 30, 60, 90 and 135min post-application. Subjective reports of comfort were also compared.Results: Treated and control eyes were not significantly different at baseline (p>0.05). Post-application, LLG increased significantly, at 30 and 60min, only in the treated eyes (p=0.005). NIBUT also increased significantly in the treated eyes only (p<0.001), at 30, 60 and 90min. TMH did not alter significantly (p>0.05). Comfort improved relative to baseline in 46% of treated and 18% of control eyes, at 30min post-application. Of those expressing a preference in comfort between the eyes, 68% preferred the liposomal spray.Conclusions: Consistent with subjective reports of improved comfort, statistically and clinically significant improvements in lipid layer thickness and tear film stability are observed in normal eyes for ≥1h after a single application of a phospholipid liposomal spray.

Objective clinical performance of ‘comfort-enhanced’ daily disposable soft contact lenses

James S. Wolffsohn, Olivia A. Hunt, Ashock Chowdhury — 2010-02-10

Abstract: Purpose: To examine the objective clinical performance of ‘comfort-enhanced’ daily disposable contact lenses over a 16-h day.Methods: Four contact lenses (Hilafilcon B, Etafilcon A Plus, Nelfilcon A and Nelfilcon A Plus) were evaluated in an investigator masked, open label trial at the end of a week's bilateral wear. Pre-lens non-invasive tear break-up time (PL-NITBUT), tear prism height, bulbar hyperaemia and ocular surface temperature (OST) were measured with the lens in situ at 8, 12 and 16h of wear.Results: There was no difference between how many hours the lenses types were worn each day (F=0.90, p=0.44). The PL-NITBUT decreased with the duration of daily lens wear (F=32.0, p<0.001) and was more stable with Nelfilcon A Plus (F=6.00, p=0.002) than with the other lenses evaluated. Bulbar blood vessels increased in coverage (F=11.5, p<0.001) but not overall redness (F=0.0, p=0.99) with the duration of daily lens wear, but there was no difference between the lenses (p>0.05). The tear prism height decreased with the duration of daily wear (F=27.0, p<0.001) and differed between lenses (F=2.9, p=0.04). The OST decreased with the duration of lens wear (F=119.7, p<0.001) and was reduced by daily disposable lens wear (F=7.88, p<0.001), but did not differ between lenses (F=0.88, p=0.45).Conclusions: Objective measures of tear film indicated a difference between the lenses evaluated for PL-NITBUT and tear prism height, but not for wearing time or bulbar conjunctival hyperaemia. Therefore clinical benefits of daily disposable ‘comfort enhancing’ contact lenses can be measured, but challenges remain in producing contact lenses that do not compromise anterior eye physiology over the whole day.

Evaluation of the effects on conjunctival tissues of Optive eyedrops over one month usage

M. Guillon, C. Maissa, S. Ho — 2010-04-01

Abstract: The objective was to compare the effect on conjunctival tissues of the repeated use, over a one-month period, of Optive compared to Hylocomod eyedrops by a population of dry eye sufferers. The rationale for the study was that among dry eye sufferers who attend eye care practices for symptomatic relief, a large number present with conjunctival anomalies evidenced by tissue staining and that conjunctival recovery is essential to their successful long term management. The hypothesis tested was that the decrease in conjunctival staining with Optive is at least as good, and possibly greater, than that with Hylocomod. The cohort population was made up of 47 subjects (11 male and 26 female) aged 42±16 years with at least mild dry eye symptoms and conjunctival and/or corneal staining. The population included contact lens wearers (n=26) and non-wearers (n=21). The subjects were randomly allocated to use one of the two study products; they were instructed to use the products as often as needed but at least three times a day. Conjunctival staining was rated on forced choice scales and measured objectively using digital photographs and image analysis. The findings showed that, whereas the staining at the start of the investigation was similar (p=0.318–0.664), staining after one month of use was significantly less with Optive than Hylocomod (p=0.028–0.002). The results demonstrated that the regular use of Optive over one month was significantly superior to Hylocomod in improving conjunctival status by producing a greater reduction in the staining of dry eye sufferers.

CET multiple choice questionnaire

2010-04-01

CET multiple choice answer sheet

2010-04-01