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ACUVUE® Eye Health Advisor ® and ACUVUE® OASYS® with HYDRACLEAR® Plus are trademarks of (insert legal entity). Johnson & Johnson Vision Care is part of (insert legal entity). (c) (insert legal entity) 2011. All other companies’ brand names mentioned herein are the trademarks of their respective owners. The opinions expressed in the Eye Health Advisor ® Magazine are those of the authors and do not necessarily represent those of Johnson & Johnson Vision Care, part of (insert legal entity). Eye Health Advisor ® A magazine from Johnson & Johnson Vision Care Eye Dryness and Contact Lenses EDITION TWO 2011 Eye Health Advisor CO NT ENT Introduction Eye Health Advisor® A magazine from Johnson & Johnson Vision Care EDITION TWO 2011 2 Introduction 3 The role of dry eye questionnaires – from symptoms to signs and diagnosis by Beáta Tapasztó, Amarilla Veres and János Németh 7 Current Diagnosis and Management of Dry Eye by Igor Petricek 13 Meibomian gland dysfunction and contact lenses… can we do better? by Christina N Grupcheva 18 Top 10 Questions on Dry Eye Symptoms Answered by Eye Care Professionals T his issue of the Eye Health Advisor ® newsletter is dedicated on dry eye problems and contact lenses. Dry eye is the most common problem, unfortunately underdiagnosed, in today’s contact lens practice. The definition of the dry eye highlights the multifactorial nature of the disease, as well as the potential damage to the ocular surface. However, the disease results in more prominent symptoms (discomfort, visual disturbance) than signs such as clinically detectable tear film instability. The most serious obstacle remains the diagnosis, including non-invasive and invasive methods. Questionnaires are easy, repeatable but obviously subjective non-invasive methods for diagnosis based on symptoms. Considering the leading role of discomfort and visual instability in diffrent enviromental conditions, questionnaires appear to be the method of choice to help eye care practitioners for screening patients for dry eye symptoms. The power of different questionnaires in case of contact lens fitting is discussed by B. Tapasztó, A. Veres and J. Németh in their overview: "The role of dry eye questionnaires – from symptoms to signs and diagnosis". However, the clinician must use specific methods for clinical diagnosis. Based on his extensive experience, Igor Petricek discusses the currently available diagnostic for dry eye methods in: "Current diagnosis and management of dry eye", where also the principles of therapeutics are highlighted. In the published literature there is agreement that most cases are evaporative followed by mixed cases of dry eye. Commonly, evaporation increases with Meibomian glands dysfunction. The problems related to are later discussed by Christina Grupcheva in: "Meibomian gland dysfunction and contact lenses... can we do better? ". Although a number of clinical and research groups are working on dry eye problems, there are still many decision related difficulties in everyday clinical practice. The approaches are different and vary from practice to practice, from country to country and depend on various factors, most important of which is probably practical experience. That's why several experts from diffrent countries have been asked specific questions and their comprehensive answers are also published in this issue. We hope that this edition of the Eye Health Advisor ® newsletter, dedicated to dry eye problems and contact lenses, will be interesting and helpful for the reader, in managing your dry eye patients, increasing thus their satisfaction as healthy contact lens wearers. 2 Eye Health Advisor A magazine from Johnson & Johnson Vision Care The role of dry eye questionnaires – from symptoms to signs and diagnosis Beáta Tapasztó, Amarilla Veres and János Németh+ INTRODUCTION Dry eye is a multifactorial disease of the ocular surface that results in symptoms of discomfort, visual disturbance and tear film instability with potential damage to the ocular surface.1,2 Contact lenses during their evolution have been associated with mechanical irritation, hypoxia, toxicity and decreased lacrimal gland secretion via the increased inflammatory cytokines and corneal nerve damage.3 Tear film function is an important factor in contact lens use.4,5 Contact lens wearers are 12 times more likely to report dry eye symptoms compared to emmetropes and five times more likely compared to spectacle-wearers.6 Discomfort and dryness are now the principal reasons for wearers stopping or reducing their contact lens wear.1,2,3 DYNAMICS AND FUNCTIONS OF THE TEAR FILM The tear film is not stable in time. It builds up quickly after the eyelids are opened, then evaporation starts, and the tear film becomes thinner and finally breaks up. Its stability plays an important role for vision from the optical point of view.7 Németh et al. found, that the corneal surface in most cases is significantly more regular at 5 seconds than at 15 seconds after a blink, which may be attributed to evaporation and thinning of the tear film. However, in a few of the healthy subjects there was an opposite trend: the tear film was found to be more regular at the later time. They attributed this contrary effect to the possibility of slow tear film build-up, which results in the tear film’s only reaching its best regularity later than 5 seconds after a blink. 8 Whether it takes the tear film a certain time after a blink to build up and achieve the most regular surface a highspeed videotopographic examination technique was developed. They found that after a blink, it takes the tear film approximately 3 to 10 seconds (tear film build-up time) to reach the most regular state. 9 The tear film forms the outer barrier of the eye against harmful organisms and mechanical, chemical injuries. The tear film involves elements of the innate immune Beáta Tapasztó MD is an Hungarian ophthalmologist who graduated with scholarship of the Hungarian Academy of Science in 1992 and became a specialist in ophthalmology in 1996. She is a member of a number of professional societies including: European Contact Lens Society, German Society of Ophthalmology, International Society for Ophthalmic Ultrasound, American Society of Ophthalmology. She practises at Semmelweis University Budapest, Medical School. Amarilla Veres, MD, PhD is a Doctor of Medicine since 1999, she holds a PhD since 2004 and specialist in ophthalmology since 2010. She participates in several research projects including Phase-3 clinical studies and experimental basic studies. Currently she is employed as an Ophthalmologist at Semmelweis University Budapest, Dept. of Ophthalmology. Prof. med. habil. János Németh, MD, PhD, DSc is Director of the Department of Ophthalmology, Semmelweis Univ., Budapest, Hungary and full time professor since 2002. He is President of the Hungarian Ophthalmological Society, Chair of the International Members Committee of the Association for Research in Vision and Ophthalmology (ARVO), Member of the Global Outreach Committee of American Academy of Ophthalmology (AAO), Member of the Board of Trustees of International Council of Ophthalmology (ICO) and other professional societies. He has published more than 264 peer reviewed articles, 9 books and 29 chapters, and presented more than 550 lectures. system of the ocular surface via its anatomical, tissue, cellular and biochemical immune protections. The tear reflex flushes and dilutes foreign material from the ocular surface, limits adhesion of microbes to facilitate their clearance in aqueous tear flow. The tear film phagocytic cells kill and remove microbes from corneal surface and its antimicrobial proteins have multiple functions that limit the ability of microbes to survive, proliferate and adhere to the ocular surface epithelium.10 + Department of Ophthalmology, Semmelweis University, Budapest, Hungary EDITION TWO 2011 Eye Eye Health Health Advisor Advisor 3 NON-INVASIVE AND INVASIVE TECHNIQUES OF OCULAR SURFACE DESCRIPTION There are many diagnostic technologies to investigate, monitor or diagnose dry eye disease. It has been shown that there are only weak correlations between the symptoms of dry eye patients and the results of different objective clinical tests for dry eye. It is difficult to measure the progression of the disease or the effect of treatments. For the diagnosis of dry eye, non-invasive, minimally invasive or invasive methods exist which are shortly summarized in Table 1 according to the Dry Eye WorkShop (DEWS) report. A non or minimally invasive technique has the major advantage that it captures data from the surface without significantly inducing reflex tearing.1 DRY EYE QUESTIONNAIRES Dry eye disease is converted into symptoms in the point of patients’ view. The External Eye Disease Working Group summarized these symptoms in 13 points.15 To be able to describe the typical dry eye symptoms the easiest way is to detect their interference with daily activities. INVASIVENESS COMMENT Non-invasive Questionnairies Non-to minimal Optical sampling s Meniscometry s Lipid layer interferometry s Tear stability analysis system s High speed video-tear film dynamics s OCT tear film imaging s OCT imaging of LIPCOF s Confocal microscopy Tear fluid sampling s Strip meniscometry s Sampling for proteomic analysis According to the DEWS report the impact of dry eye on quality of life is mediated through 1) pain and irritative symptoms, 2) effect on ocular and general health and well-being, 3) effect on perception of visual function, and 4) impact on visual performance.1 Various methods are available to assess the effect of dry eye on visual function and quality of life. Non-diseasespecific, "generic” tools like the Medical Outcome Study Short Form-36 (SF-36) have been applied to dry eye. Utility assessment, a tool used widely in medicine that permits the comparison of the effect of different diseases on quality of life based on strategies such as standard gamble, or trading years of life for disease-free years, and other techniques, has also been applied to dry eye.1 General vision-related questionnaires, such as the NEIVisual Function Questionnaire (NEI-VFQ), have been used. Disease-specific tools, like the Ocular Surface Disease Index (OSDI) and the Impact of Dry Eye on Everyday Life (IDEEL) questionnaire have also been developed and validated specifically for research on the impact of dry eye.11 Practitioners may use validated questionnaires in their clinics. According to their length and composition, symptom questionnaires explore different aspects of dry eye disease in varying depth, ranging from diagnosis alone, to the identification of precipitating factors and impact on quality of life. Table 2 summarizes the validated dry eye questionnairies used in clinical trials.1 The time taken to administer a tool may influence the choice of questionnaire for general clinical use. The Diagnostic Methodology Subcommittee concluded that the administration of a structured form to patients presenting to a clinic provides an excellent opportunity for screening patients with potential dry eye disease.1 s Osmolarity Moderate Meibomian sampling, Meibometry Meibography Invasive non-stress Staining/digital photography of surface staining Impression and brush cytology-flow cytometry Lacrimal scintigraphy Stress test Functional vision acuity Controlled adverse environment Areal BUT while staring Forceful blink test OCT: Ocular Coherence Tomography BUT: break-up time LIPCOF: lid parallel conjunctival fold Table 1: Emerging diagnostic technologies of dry eye, based on the DEWS Report.1 4 Ocular Surface Disease Index (OSDI) is a set of questions assessing the level of discomfort and interference with activities of daily living produced by ocular surface disease. It consists of 12 items: visual function, ocular symptoms, environmental triggers, and frequency with 1-week recall period. OSDI is validated in dry eye population and used as outcome measure in randomized controlled trials.1 The Contact Lens Dry Eye Questionnaire (CLDEQ) was developed to examine the distribution of dry eye symptoms among contact lens wearers. This tool measures the prevalence, frequency, and diurnal intensity of ocular surface symptoms as eye discomfort, dryness, visual disturbance, soreness and irritation, grittiness and scratchiness, foreign body sensation, burning and stinging, light sensitivity, and itching. Dryness and discomfort were found to be the most frequently reported dry eye A magazine from Johnson & Johnson Vision Care QUESTIONNAIRE’S TITLE DESCRIPTION / USE QUESTIONNAIRE’S SUMMARY McMonnies Dry Eye History Questionnaire (McMonnies, Nichols) Screening questionnaire 15 questions Canada Dry Eye Epidemiology Study (CANDEES [Doughty]) Epidemiology of dry eye symptoms in a large random sample 13 questions Ocular Surface Disease Index (OSDI [Schiffman]) Measures the severity of dry eye disease; and environmental triggers queried for the past week 12 items Salisbury Eye Evaluation (Schein, Bandeen-Roche) Population-based prevalence survey for clinical and subjective evidence of dry eye. Relation between signs and symptoms of dry eye in the elderly Standardized 6-question questionnaire Dry Eye Epidemiology Projects (deep ) questionnaire (Oden) Sensitivity and specificity of a screening questionnaire for dry eye 19 questions Women’s Health Study questionnaire (Schaumberg) Prevalence of dry eye syndrome among US women 3 items from 14-item original questionnaire National Eye InstituteVisual Function Questionnaire (NEI-VFQ [Mangione]) Useful tool for grouplevel comparisons of vision-targeted, healthrelated QoL in clinical research; not influenced by severity of underlying eye disease. 25-item questionnaire: 2 ocular pain subscale questions Dry Eye Questionnaire (DEQ, Begley et al) Habitual patient-reported symptoms and clinical signs among patients with dry eye of varying severity 21 items on prevalence, frequency, diurnal severity Contact Lens DEQ (Begley et al) Screening questionnaire for dry eye symptoms in contact lens wearers 13 questions Melbourne Visual Impairment Project (McCarty) Epidemiologic studies Self-reported symptoms elicited by interviewer-administered questionnaire NEI-Refractive Error questionnaire QoL due to refractive error 42-item questionnaire: 4 related questions Sicca Symptoms Inventory (Bowman) Epidemiologic studies for Sjögren Syndrome Inventory of both symptoms and signs of Sjögren Syndrome Bjerrum questionnaire Screening questionnaire 3-part questionnaire which includes an ocular part with 14 questions Japanese dry eye awareness questionnaire (Shimmura) 30 questions relating to symptoms and knowledge of dry eye Population-based, selfdiagnosis study to assess public awareness and symptoms of dry eye Dry eye clinic population QoL: Quality of Life Table 2: Summary of Dry Eye Questionnaires which met the criteria set by DEWS Report.1 EDITION TWO 2011 Eye Health Advisor symptoms of contact lens wearers, who reported these complaints significantly more frequently than non-wearers of contact lenses.12 McMonnies’ questionnaire focuses on risk factors for dry eye disease, including age, sex, contact lens history, dry eye symptoms, previous dry eye treatments, secondary symptoms, medical conditions associated with dry eye symptoms, and medication use. Nichols et al. reported about the performance of the CLDEQ as a screening survey. Based on the sensitivity, specificity, and receiver operator characteristic (ROC) curve analyses the CLDEQ was capable of discriminating contact lens related dry eye in comparison with McMonnies’s questionnaire. The accuracy of CLDEQ was higher compared to McMonnies’ questionnaire as the highest predictive efficiency for the CLDEQ was 1.44 (sensitivity/specificity: 87%/40%), and for the McMonnies’ 1.20 (sensitivity/specificity: 34%/86%).12 CORRELATION BETWEEN NON-INVASIVE TECHNIQUES Veres et al. visualized the morphological appearance of lidparallel conjunctival folds (LIPCOF) using optical coherence tomography (OCT) and related it to dry eye signs and symptoms measured by Dry Eye Questionnaire (DEQ). The OCT grades, the height of the folds, and the existence of tear film coverage were in good accordance with the severity of dry eye measured by DEQ. The dry eye symptom scores correlated with the height of the folds, and the absence of tear film coverage of the folds (r=0.574, P<0.001, and r=-0.527, P<0.001, respectively). The OCT LIPCOF grades correlated with the DEQ scores (r=0.494, P<0.001 and r=0.310, P=0.029).13 The non-invasive tear film breakup time (NIBUT) can be measured with Tearscope Plus® interferometer. Since contact lens can induce dry 5 eye symptoms in otherwise asymptomatic subjects, it is useful to have some idea, before fitting, which clinical tests are able to discriminate between later symptomatic or asymptomatic contact lens wearers. According to Pult et al., the LIPCOF, NIBUT and OSDI are significant discriminater for contact lens related dry eye in new contact lens wearers: the best combination is NIBUT and the sum of lid-parallel conjunctival folds and OSDI score.14 IMPLICATION TO CLINICAL PRACTICE Not all practitioners are enthusiastic about using questionnaires. However, there are significant benefits of using this non-invasive methodology. Firstly it saves qualified time as the results of the questionnaire are calculated by supporting staff and only analysed by practitioner. Secondly, it provides instantaneous information without missing any important points. Thirdly, it is a document that could be used as a baseline over time in order to evaluate the effect of therapeutic measures. Lastly it is a good modality to entertain patients in the waiting room and demonstrate them quality care. Chalmers and Begley in a very detailed paper analysed the advantages of questionnaires. 16 Looking at contact lens related dryness in particular the authors highlighted the following points: 1. Use your ears for examination. 2. Patients with symptoms but not treatment are representative for "unmet needs”. 3. Specific questions should be addressed to comfort not only as quality but as quantity (length of comfortable wear). 4. Special attention should be paid to the environment, including computer work. 5. It is important to know how dryness change upon removal of the lens. Based on those points the authors developed a short questionnaire, specially designed and tested for contact lens practice. 16 It is important for the multilingual audience of Europe, however, to know that regardless which questionnaire has been selected it should be validated in the local language in order to have the aforementioned power. SUMMARY In the recent decades even high speed videokeratoscopy, wavefront sensing, lateral shearing inferometry have been performed in natural and supressed blinking conditions to describe and measure the dry eye conditions. Although the capability of these methods to discriminate the dry eye subjects from normal subjects is based on e.g. the receiver operating curve or other statistical analysis the detection performance is still not extraordinarly high. 6 The importance to include the patient’s perception and self diagnosis of dry eye should be emphasized when evaluating parameters of ocular surface imaging. Therefore, assessing the subjective symptoms using different questionnaires is the suggested initial step of dry eye patient care. Dry eye questionnaires are a recommended part of the contact lens practice, because of the greater disparity between symptoms and signs. As already highlighted Contact Lens Dry Eye Questionnaire has greater power in contact lens cases and should be preferred, however, there is a choice of different questionnaires that should be validated for every practice. Questionnaires are simple, quick, not expensive and non invasive method for instantaneous detection of dry eye symptoms and their proper use will improve the eye care and sucessful contact lens fitting. References 1. International dry eye workshop: The definition and classification of dry eye disease: report of definition and classification subcommittee of international dry eye workshop (2007). Ocular Surface 2007;5:75-92. 2. Murube J, Németh J, Höh H, Kaynak-Hekimhan P, HorwathWinter J, Agarwal A et al. The triple classification of dry eye for practical clinical use. Eur J of Ophthalmology 2005;15:660-7. 3. Asbell PA, Lemp MA. Dry Eye Disease The clinician’s Guide to Diagnosis and Treatment. In: Dry Eye and Contact Lenses. Thieme Medical Publishers Inc. 2006;11:114-131. 4. Höh H, Schirra F, Kienecker C, Ruprecht KW. [Lid-parallel conjunctival folds are a sure diagnostic sign of dry eye]. Ophthalmologe 1995;92:802–8. 5. Jean-Pierre Guillon, Andrew Godfrey: Tears and Contact Lenses in: Contact lenses, Butterworth Heinemann Elsevier 2007 Chapter 5 111-127. 6. Nichols JJ, Ziegler C, Mitchell GL, Nichols KK. Self-reported dry eye disease across refractive modalities. IOVS 2005;46:1911-4. 7. Robert Monte´s-Mico: Role of the tear film in the optical quality of the human eye J Cataract Refract Surg 2007; 33:1631–1635. 8. Németh J, Erdélyi B, Csákány B. Corneal topography changes after a 15 second pause in blinking. J Cataract Refract Surg. 2001;27:589–592. 9. Németh J, Erdélyi B, Csákány B, Gáspár P, Soumelidis A, Kahlesz F, Lang Zs High-Speed Videotopographic Measurement of Tear Film Build-up Time Investigative Ophthalmology & Visual Science, June 2002, Vol. 43, No. 6 1783-90. 10. Michael L Nordlund, Jay S. Pepose: Corneal responses to infection p95-98. in Krachmer, Mannis, Holland CORNEA 2nd edition, Mosby Elsevier. 11. Gulati A, Sullivan R, Buring JE, et al. Validation and repeatability of a short questionnaire for dry eye syndrome. Am J Ophthalmol 2006;142:125-31. 12. Jason J. Nichols, G. Lynn Mitchell, Kelly K. Nichols, Robin Chalmers, Carolyne Begley: The Performance of the Contact Lens Dry Eye Questionnaire as a Screening Survey for Contact Lens-related Dry Eye Cornea 21(5): 469-475 2002. 13. Veres A, Tapasztó B, Kosina-Hagyó K, Somfai GM, Németh J: Imaging lid-parallel conjunctival folds with OCT and comparing its grading with the slit lamp classification in dry eye patients and normal subjects. IOVS May 2011; 52:2945-2951. 14. Pult H, Murphy PJ, Purslow C: A novel method to predict the dry eye symptoms in new contact lens wearers. Optom Vis Sci 2009;86:1042–50. 15. Petricek I.: Dry Eye. In: Berta A (ed): Red Eye. Differential diagnosis and management. Int Ophthalmol 2008;28:Suppl 1,18-31. 16. Chalmers R, Begley C. Use your ears (not your eyes) to identify CL-related dryness Optician, May 6, 2005; 229 (6000): 25-31 A magazine from Johnson & Johnson Vision Care Current Diagnosis and Management of Dry Eye Igor Petricek+ INTRODUCTION Of all conditions in eye care, dry eye is perhaps the most elusive condition. Definitions vary, epidemiology studies give widely differing figures, treatment options advocate different approaches. Perhaps the main reason why opinions differ so much is the fact that the crucial question, where to draw a line between healthy and dry eye, is still not decided upon. Perhaps it never will be, since dry eye symptoms, and not signs, are the main reason patients to see an eye doctor and symptoms are deeply subjective. That is why there are different attempts to develop a diagnostic algorithm which will provide us with objective clinical measurements, recordable and repeatable over time. The most recent definition of dry eye was published in Dry Eye WorkShop (DEWS) report (2007)1: Dry eye is a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbance, and tear film instability, with potential damage to the ocular surface. It is accompanied by increased osmolarity of the tear film and inflammation of the ocular surface. According to this definition, symptoms of discomfort are given priority as compared to signs. A new element is mentioning visual disturbance as a dry eye symptom. This is particularly important for contact lens wearers. Igor Petricek MD finished medical school in Zagreb, Croatia, 1990 and after residency in Ophthalmology he started work at Zagreb University Hospital Eye Department. From 2000 onwards he is the head of Electrophysiology and Ultrasound Laboratory at the same department. Since 2004, he is an active member of Key Faculty of the Southern European and Middle Eastern External Eye Diseases Group. Since 2008 he actively participated in various contactology meetings, mainly regarding Pathophysiology of the ocular surface in contact lens wear. In summary, his current main interests and fields of work in ophthalmology are electrophysiology of the eye, ophthalmic ultrasound, color vision, dry eye, low vision and contactology. This led to publication of 84 scientific peer reviewed texts and presentation of 71 papers. He is a member of Croatian Ophthalmology Society, European Association for Vision and Eye Research (EVER), The Association for Research in Vision and Ophthalmology (ARVO), and Tear Film and Ocular Surface Society (TFOS). that all female contact lens wearers who were using oral contraceptives experienced ocular dryness at times, as opposed to 63% of females not using oral contraceptives. Seventy six percent of male contact lens wearers experienced dry eye symptoms. A survey amongst ophthalmologists and general medical practitioners from nine Eastern European and Middle Eastern countries (Belarus, Bulgaria, Croatia, Czech Republic, Poland, Russia, Ukraine, Turkey and the United Arab Emirates) was conducted in 2004 to estimate the percentage of patients presenting with symptoms of ocular irritation and to examine differential diagnosis and treatment.2 Out of 23,569 patients screened, 25% had dry eye diagnosed as a cause of such symptoms. Contact lens wear may cause hyperosmotic shift of the tear film.5,6 The causes for this may be reduced tear stimulation caused by decreased corneal sensitivity, thus reducing blink rate, increased lens-induced tear hyperevaporation or accumulation of lens deposits in the tear film. Therefore, if a person has a borderline or moderate dry eye to start with, contact lens wear may compromise tear function to the extent that it begins to cause symptoms. Studies consistently show that of all the symptoms experienced by contact lens wearers, that of dryness is most frequent.3,4 In a survey of 100 contact lens wearers, only 25% of all patients said that they experienced no dryness symptoms.2 The same survey showed Most researchers agree today that dry eye could be subdivided into hyposecretive and hyperevaporative dry eye.7 Although most cases are of mixed ethiology, hyposecretive dry eye is caused mainly by the aqueous tear hyposecretion, and hyperevaporative dry eye by lipid + Zagreb University Hospital Eye department, Zagreb, Croatia EDITION TWO 2011 Eye Eye Health Health Advisor Advisor 7 layer disfunction, what causes aqueous hyperevaporation. Research presented at last TFOS meeting showed that out of 180 subjects, 14 (8%) had hyposecretive dry eye, 100 (55%) had evaporative dry eye, and the remaining 66 (37%) subjects had dry eye of mixed ethiology.6-8 Therefore, it is evident that (hyper)evaporative dry eye is by far the most frequent type of dry eye. Modern lifestyle, which invariably includes working at computer, is perhaps the main culprit for reduced blink rate.9 This is particularly important in contactology, since this cause of hyperevaporative dry eye is particularly frequent among contact lens wearers, compounding the problem. Hyposecretive dry eye is mainly found among the elderly and hyperevaporative among younger population from which most contact lens wearers are recruited. Main symptom of hyperevaporative dry eye is tearing, caused by the increased evaporation and condensation of aqueous tears on palpebral margins, particularly in cold weather. Hyposecretive dry eye mainly presents with symptoms of burning, grittiness and foreign body sensation. DIAGNOSTIC MODES Many standardized questionnaires are designed for this purpose as well as dozens of tests, aiming at detecting dry eye. However, it is universally known that dry eye symptoms and signs usually present poor correlations.10 The scope of this review does not permit us to get into all the intricacies of dry eye diagnostics. Instead, we will present the most frequently used diagnostic tests as well as those that are currently being investigated as promising. TEAR BREAK-UP TIME TEST (TBUT) Of all the tests, notwithstanding all its deficiencies, TBUT test is still regarded as pivotal in dry eye diagnostics. As mentioned in DEWS Report dry eye definition, tear film instability is one of the main causes of dry eye, and that is what TBUT test measures. It is easy and quick to perform and is moderately invasive. However, its interpretation depends heavily on examiner's judgement. But, since currently we have nothing better, TBUT remains as the most frequently used test in dry eye diagnosis. Apart from its dubious repeatability and unavoidable examiner's influence, the other problem with TBUT test is lack of consensus regarding cutoff value between normal and pathologic values: older papers advocate 10 seconds, while several newer ones reduce it to 5 seconds. 8 SCHIRMER TEST Schirmer test was historically the first one used in dry eye diagnosis. It still has a place in it, but with strictly defined purpose: only to measure the quantity of aqueous tear production. Any generalization of results to the overall state of tear film is grossly wrong. Actually, in hyperevaporative dry eye we often see tears dripping from the test strip- interpreting this result as "normal tear function" would mean missing the opportunity to properly diagnose and treat patient's tear dysfunction. As a cutoff value of Schirmer test, 10 milimeters of test strip wetted with tears in 5 minutes is generally accepted. LID PARALLEL CONJUNCTIVAL FOLDS (LIPCOF) A group of authors led by Prof. Hoeh in 1995 published the paper Lid-parallel conjunctival folds are a sure diagnostic sign of dry eye.11 The method described was named Lidkantenparallelen Konjunktivalen Falten, or Lid Parallel Conjunctival Folds (LIPCOF). It was presented as a very useful and innovative way of diagnosing dry eye. However, it was for a long time mentioned in relatively few published papers, and is rarely used in everyday clinical practice, especially outside Europe, where it is frequently termed conjunctivochalasis and not associated with dry eye. According to authors, the height and/or number of bulbar conjunctival folds parallel to the temporal margin of the lower eyelid are observed. Before assessment, lower eyelid is briefly lifted from the eye surface- if folds disappear, they indeed are what is described as LIPCOF. Findings are ranked as follows: s Grade 0: no folds- normal finding (not dry eye) s Grade 1: one fold above the normal tear meniscus height- mild dry eye s Grade 2: multiple folds up to the height of normal tear meniscus- moderately dry eye s Grade 3: multiple folds above normal tear meniscus height- severe dry eye (Figure 1) Figure 1: Clinical picture demonstrating grade 3 LIPCOF A magazine from Johnson & Johnson Vision Care Authors of this method claim that LIPCOF has 93% positive predictive value.11 In other words, it detects dry eye with 93% certainty. Its negative predictive value is claimed to be 76%. Furthermore, LIPCOF is not invasive, takes very short time to perform and has no additional costs as it requires use of no test strips, dyes etc. This may be particularly practical in dry eye screening in contact lens wearers, especially regarding soft contact lenses, since most ophthalmologists have at their disposal only fluorescein dye that may stain the lens or, if lens was removed to perform TBUT test, the lens cannot be reinserted until dye disappears from the eye.12 Korb et al. explain appearance of staining on lid wiper with decreased lubrication in dry eye, and consequently increased friction. LWE has been graded in Prof Korb's initial paper, and more precisely in his more recent paper.15,16 However, the fact remains that LIPCOF is very rarely, if ever, used outside the German-speaking area, the language mentioned paper was written in. DEWS or MGD (Meibomian Glands Disease) Workgroup reports do not mention it at all.1,13 One recent study reafirms the potential value of LIPCOF in dry eye screening, placing cutoff value between grades 1 and 2.14 INTERBLINK INTERVAL VISUAL ACUITY DECAY (IVAD) Nevertheless, the main disadvantages of LIPCOF remain the absence of definite reference parameter (tear meniscus height is variable between people), the subjectivity of the examiner, narrow range of grades (0-3), and lack of understanding why folds actually appear. LID WIPER EPITHELIOPATHY (LWE) Prof. Donald Korb with his coauthors has found correlation between dry eye symptoms and the appearance of inner upper eyelid lid wiper portion staining.15 In symptomatic patients, 88% had LWE.16 Lid wiper can be stained either with fluorescein or with lissamine green (Figure 2). Although not widely used in tear film diagnostics, LWE is a promising concept. Its indisputable value is in drawing attention to increased friction as one of the main causes of dry eye symptoms, the fact that was previously largely overlooked. DEWS Report included visual disturbance among most common dry eye symptoms.1 However, it does not offer any practical diagnostic test that may be used to detect and measure it. To date, it has been difficult to quantify the decay of visual acuity within the interblink interval. A new test, however, has been specifically developed and validated by the researchers at ORA Clinical Research and Development ( North Andover, Mass., USA ) to provide an accurate measure of visual function.17 The Interblink Interval Visual Acuity Decay ( IVAD ) test provides the necessary measurement of visual function in real time. A computer-based paradigm incorporates the presentation of Landolt’s C’s at the patient’s best-corrected visual acuity. Patients are instructed to track the orientation of the C by pressing a button on a keypad. As the patient’s Best Corrected Visual Acuity ( BCVA) declines during his interblink interval, the size of the stimuli increases accordingly. Visual acuity decay results are on the order of milliseconds. In the study using IVAD, there were 18 dry-eye patients and 17 age-matched controls. The researchers found that dry-eye patients could only maintain their BCVA for 8.75 ± 6.6 seconds before it started to decay, while normal patients maintained it for a statistically significant longer period of time: 19.46 ±15.97 seconds. Acuity could drop to as low as 20 / 80 in some patients. Although promising, IVAD has drawbacks. It is still too impractical for use as it uses copyrighted software and is primarily designed to be used ophthalmic drugs. Figure 2: Clinical picture demonstrating lid wiper, stained with Lissamine Green Lid wiper is part of the inner margin of the upper eyelid that exerts most pressure on the eyeball during blinking. EDITION TWO 2011 Eye Eye Health Health Advisor Advisor some serious everyday clinical and equipment, in trials of new As with LWE, its importance primarily lays in drawing attention to another overlooked aspect of dry eyeimpaired vision due to uneven tear film distribution and evaporation. That is particularly important in contact lens wearers, who may experience compounded symptoms due to contact lens desyccation. 9 LIPID LAYER THICKNESS (LLT) As was already mentioned, lipid layer is fast becoming the most investigated part of the tear film. Nowadays, its dysfunction is acknowledged as the main cause of majority of dry eye cases.8 Reduced blinking rate, something seen so frequently among contact lens wearers, also causes reduced lipid layer thickness. However, how this can be visualized? It can be assessed by using the interference phenomenon of lipid spread over aqueous tear (Figure 3). The only commercially available instruments to do this are Tearscope and Figure 4: Meibomian gland expression is with other signs of dry eye, staining correlates poorly with symptoms: one may have pronounced dry eye symptoms without any surface staining and vice versa. In summary, the following diagnostic sequence is recommended, which will not take too much time, and does not require any additional equipment: 1. 2. 3. 4. 5. 6. Case history Slit lamp examination of lid margin for blepharitis TBUT LIPCOF Meibomian Gland Expression Ocular surface staining Figure 3: Tearscopy based on interference phenomenon of lipid spread over aqueous layer. THERAPEUTIC APPROACH Tearscope Plus ® (Keeler).19 They are not widely used due to their price. Also, they are no longer produced. As with visual disturbances, that leaves stressed importance of the lipid layer on dry eye on the one hand, and lack of tools to assess it in the other. MEIBOMIAN GLAND EXPRESSION One indirect way of assessing lipid layer function is Meibomian gland expression. It was initially as well as most recently described by Prof. Korb in 2008.20 By manually applying pressure on the lower eyelid for 10-15 seconds, we can assess quantity and appearance of meibum (Figure 4). This method is again prone to examiner's subjectivity. However, it is non-invasive, requires no additional equipment and at least may give us general idea about lipid layer secretion. OCULAR SURFACE STAINING Ocular surface staining marks a more serious form of dry eye, one in which protective role of tear film has been compromised. Typically, dry eye exhibits staining in the palpebral aperture and at 6 o'clock. However, as it 10 What should be practitioners main goals in dry eye therapy? Firstly, to alleviate symptoms, and thus enhance patient's quality of life. Secondly, to prevent development of possible complications of dry eye, such as viral or bacterial infection or scarring. And last but not least, not to minimise the side effects of the therapeutic measures. ARTIFICIAL TEARS Artificial tears were and still are the mainstay of any dry eye therapy. However, they have gone a long way from just rewetting. Nowadays, their role in lubrication, and, most recently, prevention of evaporation, are increasingly gaining importance. REWETTING By volume, all artificial tears are 99% water. However, what makes them different from 100% water are demulcents that keep water on the eye long enough to provide adequate rehydration. A demulcent (derived from the Latin demulcere, "caress") is an agent that A magazine from Johnson & Johnson Vision Care forms a soothing film over a mucous membrane, relieving minor pain and inflammation of the membrane. What is more important, it can swell to many times its dry volume without losing its initial properties. After absorbing water it can slowly release it, providing long lasting rehydration. LUBRICATION Increased friction has been recognized as one of the main causes of dry eye symptoms, as shown in Lid Wiper Epitheliopathy concept. Compounds with proven lubricating effect are nowadays available in rewetting eyedrops. By reducing friction, dry eye symptoms such as grittiness and foreign body sensation are reduced. EVAPORATION PREVENTION In case of diagnosed hyperevaporative dry eye caused by lipid layer dysfunction, there was not much available to the ophthalmologist to offer his patient. However, recently there are formulations with lipid layer substitutes, presenting perhaps the biggest change in artificial tear therapy since introduction of Hydroxypropyl methylcellulose (HPMC) as an active ingredient of artificial tears in the early fifties. PRESERVATIVES As required by the Food and Drug Administration (FDA), all multidose ophthalmic solutions must contain some sort of preservative. However, not all preservatives are the same. Benzalkonium chloride (BAK) is still the most frequently used preservative. As a cationic surfactant (detergent), it disrupts lipid layer of the tear film and causes tear break-up. Therefore, BAK-containing eyedrops may actually worsen the symptoms of hyperevaporative dry eye by dissolving lipid layer. Having this in mind, it is evident that either monodose preservative-free artificial tears or those with preservatives with less adverse effects, such as higher molecular weight , are compounds of choice here. OTHER THERAPEUTIC MEASURES Change in environmental conditions (air convection and humidity, monitor position). Air-conditioned environment has low relative humidity. That is particularly evident in passenger aircraft cabins, where dry eye symptoms and contact lens intolerance may become particularly bothersome. Regarding air-conditioning in houses or cars, natural ventilation is therefore better option wherever possible. Also, placing computer monitors below eye EDITION TWO 2011 Eye Eye Health Health Advisor Advisor level will narrow the eye aperture and thus reduce ocular area from which tears evaporate. TREAT ANY EYELID DISEASE (BLEPHARITIS), EYELID HYGIENE Reduced blinking in contact lens wearers may cause Meibomian gland orifices to clog, thus compromising lipid layer function and increasing tear evaporation. This is particularly evident in persons with oily facial skin. To prevent this, eyelid hygiene (cleaning of gland orifices with clean water of commercialy available lid scrubs) is recommended on daily basis. ASSESS CONTACT LENS CARE REGIMEN Improper lens care (lens worn too long, use of improper cleaning solution etc.) may also cause tear film function to be excessively compromised. CHANGE OF CONTACT LENS MATERIAL In case none of the above can help, a change to siliconehydrogels (SiHs), may help. Eye care practitioners should base lens selection initially on publications in peer-reviewed journals and subsequently on their own experience of product performance. It has been claimed that ACUVUE ® OASYS ® with HYDRACLEAR ® PLUS (senofilcon A) lens has improved performance, especially for patients in challenging environments who may have issues with lens comfort and dryness. The enhanced wettability and lubricity of the senofilcon A material have been shown to increase levels of reported patient comfort compared with habitual lenses, even in adverse environments by reducing the disruption of the post lens tear film and reduce lid sensation during blinking. 21 The material has been shown to allow an increase in comfortable wearing time in a population of lens wearers for whom comfortable wearing time had previously been a problem. It has also been shown that senofilcon A lenses can increase patient comfort in specifically challenging situations such as computer use and driving at night. 22 CHANGE OF LENS TYPE OR WEAR REGIMEN If gas permeable contact lenses cause severe discomfort due to ocular dryness, change to soft material may be considered. In case of severe intolerance, 11 consider temporary or permanent reduction of wear time or complete discontinuation of contact lens wear. In contact lens practice diagnosis of dry eye is compulsory and should include number of tests in order to define the type of dry eye, as well the condition of the ocular surface including potential damage such as staining, lid wiper epithelopathy, LIPCOF. One must combine most appropriate methods, but very importantly this combinaation should be standardised for better repeatability and improved diagnostic value over time. As far as the problem is identified the eye care pratitioner should decide on therapeutic measures. Special attention should be payed on lens material and its property, lens modality and if applicable contact lens solutions. Careful contact lens selection and follow up of each case will improve dry eye related symptoms and ocular surface health. 15. Korb DR, Herman JP, Greiner JV, Scaffidi RC, Finnemore VM, Exford JM, Blackie CA, Douglass T. Lid Wiper Epitheliopathy and Dry Eye Symptoms. Eye and Contact Lens 2005; 31(1): 2-8. 16. Korb DR, OD, Herman JP, Blackie CA, et al. Prevalence of Lid Wiper Epitheliopathy in Subjects With Dry Eye Signs and Symptoms. Cornea 2010; 29:377–383. 17. Torkildsen G, The effects of lubricant eye drops on visual function as measured by the Inter-blink interval Visual Acuity Decay test. Clin Ophthalmol 2009; 3: 501-6. 18. Korb DR, Baron DF, Herman JP et al. Tear film lipid layer thickness as a function of blinking. Cornea 1994; 13(4): 354359. 19. Tearscope. Tearscope Plus Clinical Handbook and Tearscope Plus Instructions. Windsor, Keeler Ltd, Windsor, Berkshire; Keeler Insts Inc., Broomall, PA, 1997. 20. Korb DR, Blackie CA. Meibomian gland diagnostic expressibility: correlation with dry eye symptoms and gland location. Cornea 2008;27(10):1142–1147. 21. Riley C, Young G, Chalmers R. Prevalence of ocular surface symptoms, signs, and uncomfortable hours of wear in contact lens wearers: the effect of refitting with dailywear silicone hydrogel lenses (senofilcon a). Eye & Contact Lens, 2006; 32(6):281-6. 22. Young G, Riley CM, Chalmers RL, Hunt C. Hydrogel lens comfort in challenging environments and the effect of refitting with silicone hydrogel lenses. Optom Vis Sci, 2007; 84(4):302-8. References 1. Definition and Classification of Dry Eye. Report of the Diagnosis and Classification Subcommittee of the Dry Eye WorkShop (DEWS). Ocul Surf 2007;5:75-92. 2. Petricek I, Prost M, Popova A. The differential Diagnosis of Red Eye: A Survey of Medical Practitioners from Eastern Europe and the Middle East. Ophthalmologica 2006; 220: 229-237. 3. McMonnies CW and Ho A. Marginal dry eye diagnosis: History versus biomicroscopy. In: The Pre-ocular tear film in Health, Disease, and Contact Lens Wear 1986; ed. Holly FJ: p. 32-40. 4. Brennan NA and Efron N. Symptomatology of HEMA contact lens wear. Optom Vis Sci 1989; 66: 834-838. 5. Martin DK. Osmolality of the tear fluid in the contralateral eye during monocular contact lens wear. Acta Ophthalmol (Copenh.) 1987; 65: 551-555. 6. Farris RL, Stuchell RN and Mandel ID. Basal and reflex human tear analysis. I. Physical measurements: Osmolarity, basal volumes, and reflex flow rate. Ophthalmology 1981; 88: 852-857. 7. McCulley JP, Shine WE, Aronowicz J et al. Presumed Hyposecretory/Hyperevaporative KCS: Tear Characteristics. Trans Am Ophthalmol Soc 2003;Vol 101: 141-154. 8. TearLab presentation at TFOS, Florence, 2010. 9. Patel S, Henderson R, Bradley L, et al. Effect of visual display unit use on blink rate and tear stability. Optom Vis Sci 1991; 68:888–892. 10. Nichols KK, Nichols JJ, Mitchell GL. The lack of association between signs and symptoms in patients with dry eye disease. Cornea 2004; 23(8): 762-770. 11. Hoeh H, Schirra F, Kienecker C, Ruprecht KW. Lid-parallel conjunctival folds are a sure diagnostic sign of dry eye. Ophthalmologe. 1995; 92(6):802-8. 12. W. Sickenberger, H. Pult, B. Sickenberger. LIPCOF and contact lens wearers- a new tool to forecast subjective dryness and degree of comfort of contact lens wearers. Contactologia 2000; 22: 74-79 13. The International Workshop on Meibomian Gland Dysfunction. Investigative Ophthalmology & Visual Science, Special Issue 2011; Vol. 52, No. 4 14. Németh J, Fodor E, Berta A, Komár T, Petricek I, Higazy M, Nemec P, Prost M, Semak G, Grupcheva H, Evren O, Schollmayer P, Samaha A, Hlavackova K (2010) LIPCOF in the Diagnosis of Dry Eye- Multicenter Study. TFOS Florence (Poster). 12 A magazine from Johnson & Johnson Vision Care Meibomian gland dysfunction and contact lenses… can we do better? Christina N Grupcheva+ INTRODUCTION Meibomian glans are of great interest to eye care practitioners and researchers in the recent years, as their secretion appears to be a very important factor for tear film integrity and therefore optical quality and vision. Furthermore, those glands are important for the health of the ocular surface and the subjective appreciation of comfort. Introduction of silicone-hydrogel lenses and their hydrophobic material properties is another issue that increases interest towards the quality and quantity of the lipids in the tear film. Detailed information about the meibomian glands related research and publications can be found in the summary of the Meibomian Glands Disease Workshop (MGD) at the web page of the Tear Film Society - www.tearfilm.org. NORMAL ANATOMY AND PHYSIOLOGY OF THE MEIBOMIAN GLANDS The sebaceous glands within the lids have been described by Heinrich Meibom and named after him – Meibomian glands. Meibomian glands, unlike other Professor Christina N Grupcheva MD, PhD, DSc, FEBO, FICO(Hon) Prof CN Grupcheva is a National Professor in Ophthalmology since 2010. Her clinical and research interests and expertise are related to cornea, anterior segment, tear film, contact lenses and complex anterior segment surgery. She has published more than 100 scientific papers and 12 ophthalmology books. She regularly presents at national and international meetings on subjects of her expertise mainly as an invited lecturer. She is a member of a number of Bulgarian, European and International professional societies. sebaceous glands, do not have direct contact with hair follicles. Meibomian glands produce secretion via holocrine mechanism. Each gland has multiple secretory acini-containing meibocytes, lateral ductules, a central duct, and a terminal excretory duct that opens at the posterior lid margin (Figure 1). Meibum is delivered to the lid margin by lid movement and muscular contraction.It is assumed that orbicularis muscle and for the lower medial part the Riolan’s muscle play a key role. The secretion called maibum prevents evaporation and maintains the surface tension of the tear film.1 It also prevent contamination with skin lipids and prevents tears to flow over lid margin. The lipid layer is distributed by the lid margins and usually is 100 nm thick, however, A A B C Figure 2: Clinical appearance (biomicroscopy) of the upper Meibomian glands visualized from the conjunctival site (A) and lower lid with excretory openings (B). Transillumination for visualization of the lower meibomian glands (C) and lid margin keratinization and neovascularisation (D). + Head of the Department of Ophthalmology and Visual Science, Medical University Varna Figure 1: Schematic of the Meibomian gland anatomy and its adjacent structures important for functional integrity - lateral ductules (A), a central duct (B), and a terminal excretory duct (C) that opens at the posterior lid margin. EDITION TWO 2011 Eye Eye Health Health Advisor Advisor 13 in case of glands dysfunction it may be as thin as 14 nm. 2 Thinner lipid layer is associated with decreased break up time, which subjectively presents as low quality of vision and discomfort. 3 There are mean of 30 Meibomian glands within the upper lid tarsus and about 25 in the lower, according to different morphometric studies. 4 The length of the individual glands is reported approximately 5.5 mm in the middle of the upper lid and approximately 2 mm in the lower lid, and hence their calculated total volume is also higher: approximately double in the upper lid (26 µL) versus the lower lid (13 µL). 5 The Meibomian glands in the lower lids tend to be wider than those in the upper lids (Figure 2). Not all glands function simultaneously, and the details about functional characteristics still need to be elucidated. Because of the larger, and more numerous meibomian glands in the upper lids, researchers assume that they also have a higher secretory capacity, however, due to better accessibility of the lower lid margin the latter appears to be of greater interest in the published literature. There are many studies, but those performed by Blackie and Korb are very detailed and certainly seminal in regard to functional activity.6,7 These studies concluded that not all glands deliver oil at the same time. In addition, authors made a topographical evaluation of the Meibomian glands proving that the number of active glands in lower lids depends on their location along the lid margin. It appears to be highest in the nasal third, lower in the middle of the lid, and again a bit lower in meibomian glands at the thetemporal third. It was also observed that there is a correlation between the number of actively delivering meibomian glands in the lower eyelid and dry eye symptoms. 8 Functional regulation of the Meibomian gland is complicated. In contrast to other sebaceous glands they also have a distinct sympathetic and parasympathetic innervation. Meibomian glands are regulated by sex hormones and androgens have an up-regulating function, whereas estrogens act antagonistically. Sufficient levels of androgens are necessary in the production and secretion of normal meibum. 9 There may be an increased risk of MGD in cases of androgen insufficiency in: aging, menopause, androgen-blocking medications, Sjögren’s syndrome, and mutations within the androgen gene. Increased age is associated with decreased meibum production, along with changes in Meibomian gland orifice appearance. Clinically older individuals frequently have changes of the lid margins including keratinization, neovascularization and clogged orificia of the Meibomian glands. Histological evaluations of the meibomian glands in older individuals have revealed increased atrophy. 9 Blackie and Korb,studied the Meibomian gland 14 function of young healthy individuals and found that if a meibomian gland are active at 8 a.m., then, depending on its location along the lower lid, there was a high likelihood that it would continue to provide liquid secretion for 9 more hours.10 For example, 70% of the nasal glands, 30% of the central glands, and 20% of the temporal glands provided liquid secretion throughout 9-hour interval. If a meibomian gland was non-functional at 8 a.m., it would have sporadic activity during the day. These studies highlight the important issue about the time dependent characteristics of meibomian gland secretion.10 Each gland might have a specified period of activity, and finding the up-regulating factors in the future may help treatment of Meibomian gland dysfunction. MEIBOMIAN GLAND DYSFUNCTION According to the MGD workshop the definition of this condition is as follows: "Meibomian gland dysfunction (MGD) is a chronic, diffuse abnormality of the meibomian glands, commonly characterized by terminal duct obstruction and/or qualitative/quantitative changes in the glandular secretion. It may result in alteration of the tear film, symptoms of eye irritation, clinically apparent inflammation, and ocular surface disease.” This dysfunction may result in alteration of the tear film, and following symptoms: eye irritation, clinically apparent inflammation, ocular surface disease. Inflammation is not compulsory part of general classification of the MGD, as the pathological process may be result of the different conditions.11 The importance of MGD and its relationship to other blepharitis as inflammatory disease is obviously very important. There are number of publications with regards to causative agents for MGD. A study by Mathers et al.12 used meibography, volume of meibomian gland lipid (expressed), tear osmolarity, and Schirmer’s test to evaluate blepharitis patients. Based on these criteria the authors separated the patients into four groups: seborrheic with MGD ( 51%), obstructive MGD (21%), obstructive MGD with sicca (12%), sicca alone (16%). In this study, one of the most important highlights is that MGD is present together with normal tear flow, increased tear evaporation in itself is not sufficient to cause dry eye. In contrast, if tear flow is low together with increased tear evaporation, then dry eye is likely to be present. In summary, the report supports a strong involvement of Meibomian gland drop out and perhaps hyperkeratinization in some types of blepharitis.12 It is still unclear whether the keratinization and gland drop out are primary or secondary phenomena. In case of infective posterior blepharitis, bacterial colonization by S. epidermidis, S. aureus, and P. acnes A magazine from Johnson & Johnson Vision Care may lead to release of bacterial lipases and esterases which modifies the lipids secreted from the meibomian glands. Esterases produced by S. aureus hydrolyze cholesterol esters into proinflammatory cholesterol - isolated in chronic blepharitis cases. Unsaturated fatty acids, which are fluid at body temperature, are also a potential target of lipases and esterases. Lipases are exotoxins produced by coagulase-negative staphylococci, S. aureus, and P. acnes. Those enzimes will result into break down of triglycerides into mono and diglycerides (higher melting point) which are more solid in nature. This can plug the Meibomian gland and reduce the delivery of normal meibum onto the tear film, thus negatively affecting the integrity of the tear film. For clinical purposes MGD can be categorized 2 into four subtypes, as follows: 1. MGD alone s Asymptomatic – no symptoms and subtle signs, but altered Meibomian gland expression test. s Symptomatic (noncicatricial, cicatricial) – symptoms typical of evaporative dry eye combined with lid marginal changes and Meibomian glands drop out. 2. MGD with associated with ocular surface damage – most commonly conjunctival and corneal staining. 3. MGD-related evaporative dry eye 4. MGD associated with other ocular disorders. Figure 3: In vivo confocal microscopy (HRT II Rostock corneal module) demonstrating acinar structures of normal lid and lid (A), clinically proven MGD with neovascularization (B), inflammation around a acinar structures (C) and atrophic changes (D). and wider research applications.13 Recently HRT II Rostock corneal module allowed in vivo confocal microscopy of the Meibomian glands. This quick and non-invasive technology allows judgment of the acinar structure and adjacent tissues and dynamic follow up over time (Figure 3). Another indirect method as aforementioned is lipid pattern assessed by Tearscope. Due to expense and limited clinical availability this test is not widely used except for research projects. Furthermore, the pattern of lipids is not standardized and requires free interpretation which is associated with low repeatability. Using in vivo confocal microscopy, Ibrahim et al. made classification of the Meibomian gland presentation in 3 stages14 : 1. Typical acinar unit: the mean acinar unit density was 139±8 glands/mm2, the mean longest and shortest acinar unit diameters were 45.3±15.0 and 24.9±7.3 µm, respectively, the mean inflammatory cell density (ICD) was 13±1 cells/mm2; 2. Meibomian gland dysfunction (MGD): the MG dropout grade 2, and the MG expressibility grade 2, atrophy in the glands with extensive periglandular inflammatory cells, the mean acinar unit density was 26±3 glands/mm2, the mean longest and shortest acinar unit diameters were 67.3±27.4 and 37.9±7.1 µm, respectively, the mean ICD was 1167±10 cells/ mm2; 3. MGD (enlargement of acinar unit): the MG dropout grade was 2 and expressibility grade was 3, the mean acinar unit density was 40±5 glands/mm2, the mean longest and shortest acinar unit diameters were 133.5±62.3 and 75.0±8.1 µm, respectively, the mean ICD was 232±9 cells/mm2.14 Direct method allows visualization of the Meibomian glands by microscopy, or by meibography via transillumination through the tarsus. Meiboscopy is the quantification of meibomian gland dropout by using lid transillumination, while meibography is the same technique, but using photodocumentation, usually infrared camera, and long term record. Both methods, still have limited clinical The function of the Meibomian glands may also be judged on the basis of Meibomian gland expression. It has been introduced as a clinical method by D Korb, and it is common to express the glands by applying digital pressure through the substance of the lids.8 For research, however, standardized methods with different devices has been developed. On the basis of meibum expression, meibomian CLINICAL EVALUATION OF THE MEIBOMIAN GLANDS Meibomian glands function is judged on the basis of indirect and direct methods. The principle indirect method is tear break up time (TBUT), however, lipid layer is best judged by the Tearscope patterns. In the clinical practice TBUT is the most popular and widely used. In case of MGD the value of the TBUT is lower than 10 seconds. However, the quality of the tear film break up such as zones, extent and pattern must also be analyzed. EDITION TWO 2011 Eye Eye Health Health Advisor Advisor 15 gland orifice obstruction has been classified as: – grade 1: cloudy meibum expressed with mild pressure; – grade 2: cloudy meibum expressed with more than moderate pressure; – grade 3: meibum cannot be expressed even with strong pressure. Meibomian gland expression is also used to obtain meibomian samples for lipid analysis. When the lids are normal, light expression may be expected to expel secretion contained in the ducts, and also is possible to force presecretory lipids from the acini. In MGD much heavy expression is required. In MGD, the qualitative analysis of expressed oil may highlight: – clear fluid, – cloudy fluid, – viscous fluid containing particulate matter, – densely opaque, toothpaste-like material. To improve clinical judgment several grading scales have been developed. The scales also try to combine quantitative analysis, based on number of glands prone to expressivity: – all glands expressible, – 3–4 glands expressible, – 1–2 glands expressible, – no glands expressible. It is still debatable which tests are appropriate for asymptomatic patients, however, as a rule the more severe is the MGD the examination should include the whole range of available tests. MANAGEMENT OF THE MEIBOMIAN GLANDS DYSFUNCTION Although, there are variety of treatments they may be divided into two principal groups: lid hygiene and hot procedures with expressive massage. The first may be performed with baby shampoo or over the counter (OTC) products. Warm compresses or special devices may help Meibomian glands expression and functional improvement. In case of dry eye it should be managed appropriately. Most importantly in case of infection antimicrobials should be used, and in case of inflammation short term corticosteroids might be considered on short term basis. s adjunctive use of lubricants/artificial tears in cases of additional dry eye disease, s topical antibiotic ointments for moderate to severe cases,and s systemic tetracycline derivatives (e.g., tetracycline 250 mg four times per day or doxycycline 100 mg two times perday) for 6 weeks to several months in recurrent cases, and/or s to consider topical steroids in severe cases for a shortterm and incision and curettage with optional steroid injection in chalazion. Considering antibiotic treatment, it should be mentioned that macrolide antibiotics present immunomodulatory and anti-inflammatory effects which are separate from direct antibacterial actions.17 Furthermore tetracycline and its derivatives applied systemically present antiinflammatory and lipid-regulating properties, rather than antimicrobial effects. Tetracyclines (and in even lower dose doxacycline) inhibit lipase activity and therefore decrease free fatty acids, which destabilize the preocular tear film and promote inflammation. Excessive lipase activity and alterations of lipid composition directly influence tear stability, and may also play a role in keratinization of the lid margin and plugging of meibomian gland.17 Surgical treatments of MGD (including probing) are not widely used and manage the complications of the disease, than the disease itself. MGD AND CONTACT LENSES Contact lens problems such as deposits or transient visual disturbances and discomfort are common in patients with MGD. Proper management of existing symptomatic or asymptomatic disease is required for successful contact lens wear. Contact lenses on the other hand may be associated with decreased number of Meibomian glands or MGD, as a result of chronic trauma. It is debatable which material and which design is more traumatic to the lids. However, published literature The Moorfields Manual of Ophthalmology and The Wills Eye Manual recommend15, 16 : s warm compresses and lid massage up to four times per day for 15 minutes, Figure 4: Clinical picture of Meibomian glands expression with minimal (A), moderate (B) and heavy (C) pressure and the excessive meibum in the tear film (D). 16 A magazine from Johnson & Johnson Vision Care is not convincing about "traumatic effect” of contact lenses over Meibomian gland. Ong and Larke18 reported that 30% of contact lens wearers developed MGD after 6 months, compared with only 20% of the non– lens-wearing population. This difference appear to be statistically significant, however, neither lens type (hard, gas permeable, or soft) nor sex was significant factor. Much larger study by Hom et al.,19 demonstrated a small excess of MGD in the contact lens wear (41%) versus non-contact lens wear (38%) group, but results were not statistically significant or likely to be relevant clinically. Despite that published literature did not highlight the role of lens characteristics and modality for development and severity of the MGD, careful contact lens selection and follow up is essential to minimize possible complications. Contact lens is a part of the anterior ocular surface and has a significant interactive effect over it, especially considering the tear film. The so-called pre-contact lens tear film consists of water and lipid layers. The latter is a product of the Meibomian glands It has been proven that patients with giant papillary conjunctivitis are more likely to have Meibomian gland dysfunction with gland dropout than patients without GPC.20 Additionally, the viscosity of meibomian gland excreta is greater in lids with GPC. More recent studies have shown that contact lens wear (regardless soft lenses or gas permeable) is associated with a decrease in the number of functional Meimbonian glands. This decrease is proportional to the duration of contact lens wear. This may be correlated to literature reports for incidence of dry eye in up to 50% of contact lens wearers. Although there are no studies in the literature looking at MGD and different materials and designs one may speculate that less trauma caused by lenses with higher lubricity and lower modulus would be beneficial. Again theoretically corneo-scleral soft lenses should have less traumatic effect than gas permeable lenses. Moreover from the same point of view edge design should play a role in MGD and especially clogging of the excretory duct by epithelial cells, as initially suggested by Henriquez et al.21 Of course, material properties should be considered in case of MGD. As lipid layer is affected, hydrophobic lenses, theoretically should be contaminated easily with lipids and lipid deposition would be associated with poor wettability. In order to prevent this, eye care practitioner should consider lenses with wettable surface, and definitely frequent replacement regimen would be beneficial. In most difficult cases daily disposable lenses should be the first choice. CONCLUSIONS Meibomian gland disease is a serious clinical problem with increasing incidence and prevalence. The reasons for this increased frequency are improved diagnostics and clinical awareness, as well the greater demand for EDITION TWO 2011 Eye Eye Health Health Advisor Advisor comfort from patients. Contact lens practice is certainly the most affected specialized eye care division by the consequences of this condition. The eye care practitioner must properly diagnose and manage the problem and also select the proper material and design in order to manage, not only treat Meibomian Gland Dysfunction. References 1. Mathers WD, Lane JA. Meibomian gland lipids, evaporation, and tear film stability. Adv Exp Med Biol. 1998;438:349–360. 2. Foulks GN, Bron AJ. Meibomian gland dysfunction: a clinical scheme for description, diagnosis, classification, and grading. OculSurf. 2003;1:107–126. 3. Bron AJ, Tiffany JM. The contribution of meibomian disease to dry eye. Ocul Surf. 2004;2:149 –164. 4. Jester JV, Nicolaides N, Smith RE. Meibomian gland studies: histologic and ultrastructural investigations. Invest Ophthalmol Vis Sci. 1981;20:537–547. 5. Greiner JV, Glonek T, Korb DR, et al. Volume of the human and rabbit meibomian gland system. Adv Exp Med Biol. 1998;438: 339–343. 6. Blackie CA, Korb DR. Recovery time of an optimally secreting meibomian gland. Cornea. 2009;28:293–297. 7. Blackie CA, Korb DR. The diurnal secretory characteristics of individual meibomian glands. Cornea. 2010;29:34 –38. 8. Korb DR, Blackie CA. Meibomian gland diagnostic expressibility: correlation with dry eye symptoms and gland location. Cornea. 2008;27:1142–1147. 9. Nien CJ, Paugh JR, Massei S, Wahlert AJ, Kao WW, Jester JV.Age-related changes in the meibomian gland. Exp Eye Res. 2009; 89:1021–1027. 10. Blackie CA, Korb DR, Knop E, Bedi R, Knop N, Holland EJ.Nonobvious obstructive meibomian gland dysfunction. Cornea. 2010;29:1333–1345. 11. Arita R, Itoh K, Maeda S, et al. Proposed diagnostic criteria for obstructive meibomian gland dysfunction. Ophthalmology. 2009; 116:2058–2063. 12. Mathers WD, Shields WJ, Sachdev MS, Petroll WM, Jester JV. Meibomiangland dysfunction in chronic blepharitis. Cornea 1991;10: 277–85. 13. Foulks G, Bron AJ. A clinical description of meibomian gland dysfunction. Ocul Surf. 2003;1:107–126. 14. Ibrahim OM. Matsumoto Y. Dogru M. Adan ES. Wakamatsu TH. Goto T. Negishi K. Tsubota K. Ophthalmology. 117(4):665-72, 2010 Apr. 15. Smith GT, Dart J. External eye disease. In: Jackson TL, ed. MoorfieldsManual of Ophthalmology. Philadelphia: Mosby Elsevier;Chap 4:2008. 16. Ehler J, Shah ChP. Wills Eye Manual. Philadelphia: Lippincott Williams & Wilkins; 2008. 17. Bertino JS. Impact of antibiotic resistance in the management ofocular infections: the role of current and future antibiotics. Clin Ophthalmol. 2009;3:507–521. 18. Ong BL, Larke JR. Meibomian gland dysfunction: some clinical, biochemical and physical observations. Ophthalmic Physiol Opt.1990;10:144–148. 19. Hom MM, Martinson JR, Knapp LL, Paugh JR. Prevalence of meibomian gland dysfunction. Optom Vis Sci. 1990;67:710– 712. 20. Mathers WD, Billborough M. Meibomian gland function and giant papillary conjunctivitis. Am J Ophthalmol. 1992;114:188– 192. 21. Henriquez AS, Korb DR. Meibomian glands and contact lens wear. Br J Ophthalmol. 1981;65:108–111. 17 Top 10 Questions on Dry Eye Symptoms Answered by Eye Care Professionals 1 WHAT IS THE MOST COMMON CAUSE OF DRY EYE SYMPTOMS IN YOUR PRACTICE? Dr. Anna Maria Ambroziak, Warsaw - Poland Based on the published literature, every fifth patient approaching an eye care practitioner presents one or more symptoms of dry eye. My own, long term experience demonstrates that the problem affects a large group of patients, but most of those patients have been previously underdiagnosed, perhaps because the applied diagnostic criteria are not straightforward. Dry eye has significant implications and requires a careful approach, particularly within the group of contact lens users. The most common cause of the disorder of tear film integrity and stability, in my experience, definitely is the meibomian glands dysfunction, usually associated with unsettled regulation of oestrogen-related secretion. Therefore, dry eye caused by the disorder of the lipid layer and excessive tear film evaporation affects mostly women, both young taking contraceptives, and older ones, particularly, during the menopausal period, whether they are subjected to hormonal therapy or not. The most common causes, however, are qualitative and quantitative blinking disorders due to computer work, reading or watching TV. Dry eye symptoms among children and teenagers are reasonably frequent, though unnoticed ailment significantly associated with occurring, and not always treated dermatological issues. For instance, currently common practice of treating acne with oral Accutane (isotretinoin), on a certain length and dosage, leads to dry eye symptoms in all patients. In the era of modern materials and the possibility of fitting daily disposable silicone-hydrogel contact lenses it should be highlighted that disorders of the eye surface are not, in any way, contraindications of safe contact lens wearing. 2 DO YOU USE QUESTIONNAIRES TO IDENTIFY YOUR DRY EYE PATIENTS AND HOW DO THEY WORK? Dr. Tomas Vido, Prague - Czech Republic Although I am familiar with several dry eye questionnaires that have been developed in order 18 to assist us, as clinicians, in discovering our dry eye patients, I have never really used them extensively in my practice since now. There are many reasons, but the most important one is that in my very busy practice, questionnaires would fit with some difficulty. My patients prefer to communicate in person with me or with the supporting staff, and they really do not enjoy "working” on filling in papers, while being in the waiting room. However, when I am taking history I always use questions related to dry eye symptoms. The questions are modified and customized for each particular patient, but the three main areas are: symptoms of dry eye such as discomfort, irritation and transient visual disturbances, symptoms’ alterations influenced by different environments and impact on dry eye symptoms on patient quality of life. I usually take notes on those and then I use similar kind of questions at the follow up visits. I do believe that in direct communication the eye care professional can achieve better objectivity, leading the patients and helping them for retrospective self evaluation of their dry eye symptoms. However, I believe that in some communities, dry eye questionnaires might work best and they are definitely invaluable for research studies but also for day-to-day practice. 3 WHAT IS THE DIAGNOSTIC DRY EYE TEST OF YOUR CHOICE? Dr. Rosella Fonte, Verona - Italy In my clinical practice I prefer to adopt a procedure, rather than a single test that helps me in making a differential diagnosis of the dry eye condition, and it is as follows: first I use the phenol red test, to rule out a problem of quantity of the tear film (or, in alternative the evaluation of the tear prism and his height and width). If with this result, I can exclude a tear volume problem, (and after looking at the picture of the tear film interference), then I need to determine whether the problem is secondary to a lack of the mucin or lipid components of the tear film. So I use the lissamine green test, also seeking the presence of lid wiper epitheliopathy and highlighting features related to the mucin component. Finally, through the use of the fluorescein and the observation of the Meibomian glands, I can determine the problems related to the lipid component. It' s a three-stage procedure, fast, accurate and valid, A magazine from Johnson & Johnson Vision Care which in my hands allows, in a reasonable time, and during the routine contact lens exam, not to miss any of the components of the tear film. Therefore identifying the true nature of the problem, I can plan a strategy to improve the visual comfort of the patient. 4 WHAT IS THE MOST COMMON REASON FOR DRY EYE SYMPTOMS IN CONTACT LENS WEARERS? Dr. Deniz Oral, Istanbul - Turkey Almost half of the contact lens wearers report dryness to some degree, and these symptoms are caused by a combination of different factors. While no single reason stands out as the most common, the more frequently encountered causes of dryness in contact lens wearers are decreased tear volume and tear instability. Studies showed that contact lens wearers with dryness symptoms have lower tear meniscus volumes. Although decrease in corneal sensitivity is proposed as a cause of reduced tear production, it is still not clear if long term contact lens wear decreases tear production. Decreased tear meniscus volume and increased tear film osmolarity has been linked to increased evaporation rather than decreased tear production in contact lens users with dryness. Tear instability results from dysfunction of the meibomian glands and presents with decreased pre-lens lipid layer thickness and rapid tear film break-up. Meibomian dysfunction may be the skin property of an individual, may result from contact lens wear, or combination of both. While meibomian gland loss is normally an age related change in the eyelids, chronic irritation from contact lenses seems to accelerate this process especially in the upper eyelid. The extent of meibomian gland loss is reportedly related to the duration of contact lens wear. Along with meibomian gland dysfunction, true blepharitis also causes tear film instability. Suppressed blink reflex which is most notably caused by computer use, and results in prolongation of blink intervals, that further exacerbates the dryness symptoms caused by tear film instability. same: there are different causes beneath the condition as well as different related symptoms. If one lens works well for a particular patient, this doesn’t necessary mean it will work for other patients as well. Considering it’s hard to judge which kind of lens will work better on a particular patient with dry eye symptoms, it could be important I experimentally fit one lens after another, recording carefully objective and subjective responses. In patients with dry eye symptoms I consider mostly three characteristics of soft contact lenses (CLs): nature of materials including presence of wetting agent, CLs parameters, and frequency of replacement. These characteristics could improve tolerance in patients with dry eye symptoms for different reasons: slower lens water dehydration rate, better stability of pre-lens tear film, reduction of deposits on lens surface. If we consider the first characteristic, there are a lot of specific aspects of soft CLs materials that could be managed in order to improve comfort in patients with dry eye symptoms: water content, dehydration properties (linked to free water and bound water content), ionic charge, wettability, thickness. In particular Silicone Hydrogels materials have been demonstrated helpful in those patients due to their excellent dehydration stability. Also the availability of a wetting agent into the lens provides better wettability, decreases the friction between the lid and lens surface and is believed to improve comfort. This is of particular benefit for daily disposable lenses. Lens parameters are important for the vulnerable anterior ocular surface of the dry eye patient and it is compulsory to pay attention to the lens–lid interaction, lens movement and perhaps the corneal staining characteristics. Lastly useful characteristic is the possibility to discharge the lens after use. This opportunity, given by daily disposable, eliminates every problem that is due to the build up of surface deposits. 6 DO YOU FIT WITH CONTACT LENSES PATIENTS WHO ARE DIAGNOSED WITH MEIBOMIAN GLAND DYSFUNCTION? Dr. Heiko Pult, Weinheim - Germany 5 WHICH LENS CHARACTERISTICS YOU CONSIDER MOSTLY IN PATIENTS WITH DRY EYE SYMPTOMS? Dr. Fabrizio Zeri, Rome - Italy First of all my clinical approach to this topic is quite empirical. Patients with dry eye symptoms are not all the EDITION TWO 2011 Eye Eye Health Health Advisor Advisor Meibomian gland dysfunction ( MGD) is one of the most common causes of an lipid-layer abnormality and a sufficient lipid-layer is fundamental to stabilize the tear film especially in contact lens wear. In fact, daily lid hygiene is useful to reduce dry eye symptoms and improve tear film. In more pronounced MGD the use of warm and moist compresses plus lid hygiene is effective in improving contact lens comfort. This works very well when former happy experienced lens wearers -no suffering from MGD - are claiming 19 dry eye symptoms. We educate naive MGD lens wearers in MGD treatment before fitting. Those who agree are mostly able to wear lenses with sufficient comfort. Therefore MGD is not an exclusion criterion of contact lenses with proper management there is a high chance to succeed. To improve compliance we apply digital imaging of the ocular surface including infra-red non-contact meibography. Photographs allow monitoring MGD status. Meibography is a technique to visualize the meibomian glands' morphology. It is one of the most important tools in MGD diagnose. We are using a self-built meibograph, but an alternative option is using the built in infra-red cameras of topographers or Scheimpflug cameras. To facilitate comfortable eversion of the patients' eyelids and better images, slight optical and software modifications are vital. However updated devices plus appropriate software are just coming on the market. Even though untreated MGD is one of the most common causes of dry eye, proper treatment can help the patient wearing contact lenses successfully. Good education and continuous monitoring including meibography is fundamental. 7 WHAT IS YOUR OPINION ON COMBINATION CONTACT LENSES, MAKE UP AND DRYNESS? Dr. Arleta Waszczykowska Łód , Poland Make-up around eyes may intensify symptoms of dry eye and become the source of infection. Every single use of cosmetics poses the risk of growth of air-borne bacteria or pathogens located on the skin. Preservatives enclosed in cosmetic products minimize the risk of microorganisms growth but simultaneously may irritate the skin in sensitive individuals provoking allergic or even toxic reaction. There are many people allergic to aromatic compounds or other substances present in cosmetics like rosin, nickel or lanolin. To limit the source of additional inflammatory conditions of eye globe surface, make-up should be put on the skin after lens insertion, and removed just after lens removal. One should avoid oily cosmetics, put mascara only on the eyelashes endings, and underline the lower eyelid below the line of eyelashes. Application of make up on the lower lid margin is often associated with chronic meibomian gland disease. It is not recommended to use metallic eye shadows thickening and prolonging eyelashes mascaras with brocade or silk, because they may act like foreign bodies when located in conjunctival sac. There are contradictory opinions about waterproof make-up used 20 by contact lens wearers. On the one hand waterproof make-up minimizes the risk of cosmetics smearing during administration of moisturizing drops but on the other hand removal of waterproof make-up requires more oily and skin irritating cosmetics. Make-up removal should be performed very gently and in the direction of eyelashes to reduce the risk of corneal erosion. 8 DO YOU SEE ANY BENEFITS OF DAILY DISPOSABLE LENSES IN PATIENTS WITH DRY EYE SYMPTOMS? Dr. Bassima Aldelaigan, Riyadh Kingdom of Saudi Arabia Hot dry climate, air conditions and windy weather, all can contribute in causing dry eyes. Many patients drop out of contact lens wear, because of poor tolerance to wearing contact lens more than few hours a day. In our practices, every day we face patients who suffer from dry eyes, and drop out of contact lens (CL) wear because of extreme discomfort and intolerance. Symptoms like dryness, grittiness, redness and discomfort are common problems during contact lens wear. It is practitioner’s role to investigate the cause of the discomfort, and effectively manage these patients, to prevent contact lens drop outs. I have found that, switching patients to daily disposable contact lens has alleviated many of their symptoms, like foreign body sensation, grittiness and red eyes. Daily disposable lenses are proven to be the most convenient, healthier choice especially for patients in challenging environments and those who are suffering from dry eyes and other ocular problems. Now when daily disposable lenses comes in a silicone hydrogel (SiH) material, we can get the benefit of having a fresh clean pair with the advantage of the increased oxygen transmissibility provided by SiH lenses. Studies have shown that patients wearing SiH lenses report higher level of comfort comparing to patients wearing hydrogel lenses. 9 WHAT IS YOUR THERAPEUTIC APPROACH IN CONTACT LENS WEARERS WITH MEIBOMIAN GLAND DYSFUNCTION? Dr. Zeynep Ozbek, Izmir - Turkey Meibomian glands are modified sebaceous glands located in the posterior portion of the lid margin. They secrete the outer lipid layer of the precorneal tear A magazine from Johnson & Johnson Vision Care film, render the lubricant action during blinking as well as minimize evaporation and construct the appropriate surface tension of the tear film between blinks. Therefore they have an important contribution to both the comfort and visual quality in daily life. Meibomian gland dysfunction can manifest itself by simple dry eye symptoms such as photophobia, burning, stinging, foreign body sensation since decreased lipid secretion to the tear film will cause reduced break-up time. These symptoms may be even worse in a contact lens wearer. Surprisingly the situation is easily overlooked although not uncommon. Usually, upon hearing complaints of dry eyes, the eye care practitioner will focus on the cornea and bulbar conjunctiva looking for clues of reduced wetting. However, the real clue in meibomian gland dysfunction lies in the lid margin. Usually the gland orifices will be capped by small oil globules, the tear film appears oily and foamy, sometimes froth accumulates on the lid margin. In longstanding cases, clogging of the orifices causes inflammation due to staphylococcal exotoxins and this leads to hyperemia, thickening and telengectesias. I prefer to start with lid hygiene and warm compresses after the lenses are out. If there are signs of inflammation I may prefer refrainment from contacts for a couple of weeks, antistaphyloccal therapy such as fucidic acid and some weak steroids additionally. If I see frequent flare-ups I do not hesitate to start oral doxycycline and go on at least for 6 weeks. 10 The second step is to switch our patients to silicone-hydrogel lenses giving preference to frequent replacement. In our practice 45% of patients with dry eye symptoms use silicone-hydrogel planned replacement lenses and 37% use one-day lenses. The third step aimed to maintain the volume of tear fluid on the ocular surface. To relieve symptoms and improve the comfort, we recommend moisturizing eye drops before insertion and after removal of the lenses. They can also be used if needed during the day. We recommend the use of moisturizing drops without preservatives, or drops containing biodegradable preservatives. In case of persistent dry eye symptoms, regardless of rewetting drops, we consider lacrimal plugs. Sometimes, gas-permeable lenses can be an option. The fourth step is to modify the wearing time and modality. We do not recommend extended wear lenses for dry eye patients and sometimes our patients get the advice to reduce wearing time during specific tasks such as working on a computer. Management of dry eye disease today is a challenge due to lack of universal therapy. Therefore the eye care practitioner must find the best approach for every single case. WHAT IS YOUR THERAPEUTIC APPROACH IN CONTACT LENS WEARERS WITH DRY EYE SYMPTOMS? Dr. Olga Lobanova, Samara - Russia The therapeutic approach to the management of patients with dry eye syndrome include: normalization of the evaporation of tears, proper choice of contact lens and care system, suitable contact lens wearing time, use of moisturizing drops and if indicated antiinflammatory therapy. We follow a phased approach to the treatment of dry eye disease, paying attention to the severity of the disease and the response to the therapy. The first step is aimed at stabilizing the tear film and decrease evaporation of tears by normalization of the lipid layer. In our practice, we recommend warm compresses, followed by a massage and lid hygiene. In case of indications, local anti-inflammatory therapy is also added. The course of treatment is usually 10-15 days. For control we are also using ocular protection index (OPI), ocular surface disease index (OSDI) and staining of the ocular surface. EDITION TWO 2011 Eye Eye Health Health Advisor Advisor 21