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

Measurement of Symptoms Pre- and Post-treatment of Dry Eye Syndromes

: Valid assessment of dry eye syndrome symptoms is essential for diagnosis and for making treatment decisions and monitoring responses to treatment. Notwithstanding the desirability of being able to measure across several assessment domains to gauge the influence of symptom burden on the quality of life, the time-consuming nature of such assessments may make them unsuitable for routine clinical use. This review of symptom assessment methods examines the relative merits of visual analogue and Likert scales. Also examined are ways in which symptoms can be influenced by comorbid diseases and associated medications, and how the validity of assessing treatment efficacy could be compounded by natural progression of a dry eye syndrome apart from either favorable, neutral, or adverse responses to treatment. Follow-up assessments may also be biased by patient expectations. How validity of responses could be improved by the instructional use of a demonstration scale is described and illustrated. Personal instruction is suggested for patients anticipated to have age- or language-related difficulties but for some patients instruction could be successfully self-directed. A comparison of methods used to monitor dry eye syndrome treatment has allowed recommendations to be made for a method of using visual analogue scales which incorporates features which have been demonstrated to be advantageous in previous studies. The continuous nature of a visual analogue scale allows for smaller changes to be recorded with associated better discriminating capacity. More powerful statistical analysis of findings is possible when using visual analogue scales. Reference to previous assessment scores and exactly the same scale anchors improve the reliability of measurements of change in symptoms over time.

New Methods for Quantification of Visual Photosensitivity Threshold and Symptoms

PURPOSE

Visual photosensitivity is a common symptom difficult to measure and diagnose, and is found in many ocular and neurological disorders. We developed two novel reproducible quantitative assessments of visual photosensitivity.

METHODS

We designed and built the ocular photosensitivity analyzer (OPA), an automated instrument to determine light intensity visual photosensitivity threshold (VPT), and developed the Visual Light Sensitivity Questionnaire-8 (VLSQ-8), an eight-question survey to assess the presence and severity of photosensitivity symptoms. We evaluated the test-retest variability and obtained normative values of these two approaches in 35 healthy normal subjects, distributed evenly over five age groups from eight to 60 years. Each subject underwent two test sessions, each with VLSQ-8, eye examination, and OPA, four weeks apart, between April 2015 and June 2016.

RESULTS

Log-transformed VPTs (log₁₀lux) and VLSQ-8 results were highly reproducible between the two sessions (VPT intraclass correlation coefficient [ICC] = 0.86; 95% confidence interval [CI] = 0.71-0.93; binocular testing, VLSQ-items ICC range = 0.53-0.87). No consistent significant differences in VPTs were found with monocular (P = 0.053, session 1) or binocular (P = 0.26) testing. Subjects in age group >30 to 40 years had significantly higher VPTs than those in other age groups (P ≤ 0.011) except the >40 to 50 years age group (P = 0.11). Photosensitivity symptoms assessed by the VLSQ-8 generally were low and highly reproducible with ≥88% of responses between the 2 sessions being within one category of each other.

CONCLUSIONS

Our results provide reliability data and normative results toward validation of two novel approaches to quantify visual photosensitivity and provide support for their potential use in ocular and neurologic conditions as well as in clinical trials.

TRANSLATIONAL RELEVANCE

The new quantitative photosensitivity approaches are potential measures to characterize disease severity, monitor disease progression, and evaluate treatment efficacy.

TFOS DEWS II Sex, Gender, and Hormones Report

One of the most compelling features of dry eye disease (DED) is that it occurs more frequently in women than men. In fact, the female sex is a significant risk factor for the development of DED. This sex-related difference in DED prevalence is attributed in large part to the effects of sex steroids (e.g. androgens, estrogens), hypothalamic-pituitary hormones, glucocorticoids, insulin, insulin-like growth factor 1 and thyroid hormones, as well as to the sex chromosome complement, sex-specific autosomal factors and epigenetics (e.g. microRNAs). In addition to sex, gender also appears to be a risk factor for DED. "Gender" and "sex" are words that are often used interchangeably, but they have distinct meanings. "Gender" refers to a person's self-representation as a man or woman, whereas "sex" distinguishes males and females based on their biological characteristics. Both gender and sex affect DED risk, presentation of the disease, immune responses, pain, care-seeking behaviors, service utilization, and myriad other facets of eye health. Overall, sex, gender and hormones play a major role in the regulation of ocular surface and adnexal tissues, and in the difference in DED prevalence between women and men. The purpose of this Subcommittee report is to review and critique the nature of this role, as well as to recommend areas for future research to advance our understanding of the interrelationships between sex, gender, hormones and DED.

TFOS DEWS II Epidemiology Report

The subcommittee reviewed the prevalence, incidence, risk factors, natural history, morbidity and questionnaires reported in epidemiological studies of dry eye disease (DED). A meta-analysis of published prevalence data estimated the impact of age and sex. Global mapping of prevalence was undertaken. The prevalence of DED ranged from 5 to 50%. The prevalence of signs was higher and more variable than symptoms. There were limited prevalence studies in youth and in populations south of the equator. The meta-analysis confirmed that prevalence increases with age, however signs showed a greater increase per decade than symptoms. Women have a higher prevalence of DED than men, although differences become significant only with age. Risk factors were categorized as modifiable/non-modifiable, and as consistent, probable or inconclusive. Asian ethnicity was a mostly consistent risk factor. The economic burden and impact of DED on vision, quality of life, work productivity, psychological and physical impact of pain, are considerable, particularly costs due to reduced work productivity. Questionnaires used to evaluate DED vary in their utility. Future research should establish the prevalence of disease of varying severity, the incidence in different populations and potential risk factors such as youth and digital device usage. Geospatial mapping might elucidate the impact of climate, environment and socioeconomic factors. Given the limited study of the natural history of treated and untreated DED, this remains an important area for future research.

The Potential Role for Early Biomarker Testing as Part of a Modern, Multidisciplinary Approach to Sjögren's Syndrome Diagnosis

Sjögren's syndrome (SS) is a chronic and progressive multisystem autoimmune disease typically managed by rheumatologists. Diagnostic delays are common, due in large part to the non-specific and variable nature of SS symptoms and the slow progression of disease. The hallmark characteristics of SS are dry eye and dry mouth, but there are a broad range of other possible symptoms such as joint and muscle pain, skin rashes, chronic dry cough, vaginal dryness, extremity numbness or tingling, and disabling fatigue. Given that dry eye and dry mouth are typically the earliest presenting complaints, eye care clinicians and dental professionals are often the first point of medical contact and can provide critical collaboration with rheumatologists to facilitate both timely diagnosis and ongoing care of patients with SS. Current diagnostic criteria advocated by the American College of Rheumatology are predicated on the presence of signs/symptoms suggestive of SS along with at least two objective factors such as traditional biomarker positivity, salivary gland biopsy findings, and/or presence of keratoconjunctivitis sicca. Traditional biomarkers for SS include the autoantibodies anti-Sjögren's syndrome-related antigen A (SS-A/Ro), anti-Sjögren's syndrome-related antigen B (SS-B/La), antinuclear antibody (ANA) titers, and rheumatoid factor (RF). While diagnostically useful, these biomarkers have low specificity for SS and are not always positive, especially in early cases of SS. Several newly-identified biomarkers for SS include autoantibodies to proteins specific to the salivary and lacrimal glands [SP-1 (salivary gland protein-1), PSP (parotid secretory protein), CA-6 (carbonic anhydrase VI)]. Data suggest that these novel biomarkers may appear earlier in the course of disease and are often identified in cases that test negative to traditional biomarkers. The Sjö^® test is a commercially available diagnostic panel that incorporates testing for traditional SS biomarkers (anti-SS-A/Ro, anti-SS-B/La, ANA, and RF), as well as three novel, proprietary early biomarkers (antibodies to SP-1, PSP, and CA-6) which provide greater sensitivity and specificity than traditional biomarker testing alone. Timely diagnosis of SS requires appropriate clinical vigilance for potential SS symptoms, referral and collaborative communication among rheumatology, ophthalmology, and oral care professions, and proactive differential work-up that includes both physical and laboratory evaluations.

Epidemiology of Meibomian Gland Dysfunction in an Elderly Population

PURPOSE

To study the epidemiology of meibomian gland (MG) dysfunction in an elderly, predominantly male population.

METHODS

Prospective study of 233 subjects seen in the Miami Veterans Affairs eye clinic. Patients underwent a complete ocular surface examination, including dry eye questionnaires and tear assessments (osmolarity, tear breakup time, corneal staining, Schirmer test). The main outcome measures were correlations between MG parameters and demographics, dry eye symptoms, and tear parameters. The studied MG parameters were eyelid vascularity and meibum quality; a score ≥2 for either parameter was considered abnormal.

RESULTS

Mean age of the 233 subjects was 63 years (SD = 11); 91% were male and 59% had at least 1 abnormal MG parameter (abnormal quality 55%; vascularity 17%). Demographically, patients with abnormal MG parameters were significantly older than their counterparts without these findings. Whites were more likely to have abnormal eyelid vascularity compared with blacks [n = 36 (31%) vs. n = 1 (1%), P < 0.0005] but no differences were noted between races with respect to meibum quality. Abnormal meibum quality, but not abnormal vascularity, was significantly associated with more severe dry eye symptoms. Similarly, abnormal meibum quality, but not eyelid vascularity, was significantly associated with worse dry eye signs, including decreased tear breakup time and increased corneal staining (P < 0.05 for all).

CONCLUSIONS

MG dysfunction is a frequent finding in an elderly, predominantly male population with racial differences noted in the frequency of abnormal eyelid vascularity but not in MG quality. Abnormal meibum quality was significantly associated with more severe dry eye symptoms and signs.

Association Between Migraine and Dry Eye Disease: A Nationwide Population-Based Study

PURPOSE

Despite the possible association between migraine and dry eye disease (DED), there are only a few studies investigating this link in a relatively limited number of patients. Therefore, we have analyzed the relationship between migraine and DED in the Korean population.

MATERIALS AND METHODS

This population-based cross-sectional study included 14 329 adults participating in the fifth annual Korea National Health and Nutrition Examination Survey from 2010 to 2012. Migraine, DED diagnosis, and DED symptoms were assessed using questionnaires and surveys. Data were analyzed using logistic regression to determine the association of migraine with DED while controlling for demographic, lifestyle, and medical factors.

RESULTS

Individuals with migraine were more likely to report a DED diagnosis (14.4% vs. 8.2%, p < 0.0001) and DED symptoms (22.0% vs. 15.1%, p < 0.0001). In a multivariate analysis, the association between migraine and DED diagnosis was significant after adjustments (OR, 1.577; 95% CI, 1.340-1.855). The association between migraine and DED symptoms showed a similar pattern (OR, 1.304; 95%CI, 1.151-1.502).

CONCLUSIONS

Although a causal relationship was not revealed, we found that patients who had a lifetime history of migraine were more likely to suffer from DED than individuals who did not present with headaches; this association may require confirmation. Large prospective cohort studies are required to evaluate the association between migraine and DED, as well as the influence of DED treatment on the frequency and severity of migraine attacks.

Evidence of central sensitisation in those with dry eye symptoms and neuropathic-like ocular pain complaints: incomplete response to topical anaesthesia and generalised heightened sensitivity to evoked pain

OBJECTIVE

To evaluate how closely neuropathic-like ocular pain (NOP) symptoms align with a metric of central sensitisation (ie, the presence of persistent ocular pain after topical anaesthetic placement) in individuals with dry eye (DE) symptoms.

DESIGN

Cross-sectional study of 224 individuals with DE symptoms seen in the Miami Veterans Affairs eye clinic. An evaluation was performed consisting of questionnaires regarding DE symptoms, NOP descriptors and evoked pain sensitivity testing on the forehead and forearm, followed by a comprehensive ocular surface examination including corneal mechanical sensitivity testing. Subsequent analyses were performed to examine for differences between those with and without ocular pain after topical anaesthetic placement.

RESULTS

The mean age was 62 years with 91% being men. DE symptoms and NOP symptoms were higher in subjects with persistent ocular pain after anaesthesia. Most DE signs were not related to persistent pain, with the exception of meibum quality. Individuals with persistent ocular pain also demonstrated greater sensitivity to evoked pain at testing sites on the forehead and forearm. When examining receiver operator characteristic curves considering persistent pain as a gold standard for central sensitisation within the corneal pathway, intensity of ocular pain ratings, Ocular Surface Disease Index scores and sensitivity to light provided the most robust relationships, each with an area under the curve of 0.72.

CONCLUSIONS

Individuals with DE symptoms and persistent ocular pain after topical proparacaine (a marker of central sensitisation to pain) more frequently report NOP-like symptoms and demonstrate increased sensitivity to evoked pain.

Bulbar conjunctival microvascular responses in dry eye

PURPOSE

Conjunctival microvascular responses may be a surrogate metric of efferent neural pathway function innervating the ocular surface as changes in blood flow occur within seconds after a stimulus. As somatosensory dysfunction may partially underlie dry eye (DE), in this study we evaluate whether bulbar conjunctival microvascular alterations correlate with various aspects of DE.

METHODS

Fifty-six DE patients were prospectively recruited from a Veterans Affairs ophthalmology clinic over an 11-month period. DE symptoms and ocular pain were assessed along with DE signs. A novel functional slit lamp biomicroscope (FSLB) was used to image the temporal bulbar conjunctiva from the right eye before and after central corneal stimulation with an air puff. Blood flow velocities were measured and noninvasive microvascular perfusion maps (nMPMs) were created.

RESULTS

The bulbar blood flow velocity was 0.50 ± 0.15 mm/s at baseline and increased to 0.55 ± 0.17 mm/s after stimulation (P < 0.001); the average change in velocity was 0.05 ± 0.09. nMPMs values and venule diameter, on the other hand, did not significantly increase after stimulation (1.64 ± 0.004 at baseline, 1.65 ± 0.04 after stimulation, P = 0.22 and 22.13 ± 1.84 μm at baseline, 22.21 ± 2.04 μm after stimulation, P = 0.73, respectively). Baseline blood flow velocity positively associated with Schirmer scores (r = 0.40, P = 0.002). Those with higher self-rated wind hyperalgesia demonstrated less change in blood flow velocity (r = -0.268, P = 0.046) after air stimulation on the central cornea.

CONCLUSION

Conjunctival blood flow velocity, but not vessel diameter or complexity, increases after wind stimuli. Baseline flow positively correlated with Schirmer scores while change in flow negatively correlated with self-reported wind hyperalgesia.

Frequency and risk factors associated with dry eye in patients attending a tertiary care ophthalmology center in Mexico City

PURPOSE

The purpose of this study was to ascertain the frequency and risk factors of dry eye (DE) among patients attending a tertiary care ophthalmology center in Mexico.

METHODS

Approximately 338 consecutive new patients attending a tertiary care ophthalmology center in Mexico City underwent an ocular surface examination, which included tear film break-up time, fluorescein corneal staining, Schirmer's test, and evaluation of meibum quality. Symptoms of DE were evaluated by the Ocular Surface Disease Index and Dry Eye Questionnaire-5. Information on demographics, exposures, past medical and ocular history, and medications was also collected.

RESULTS

The frequency of severe DE symptoms was found to be 43% based on the Ocular Surface Disease Index and 30% based on Dry Eye Questionnaire-5. Risk factors significantly associated with increased DE symptoms included dry mouth and gastrointestinal ulcer medications. With regard to signs, aqueous tear deficiency was a less-frequent finding (22%) in our population than evaporative deficiency (94%). Risk factors associated with aqueous tear deficiency were dry mouth and diuretic use. No risk factors were associated with evaporative deficiency. Risk factors associated with meibomian gland dysfunction included old age, male sex, arthritis, and use of an antihypertensive. The only risk factor associated with corneal staining was dry mouth.

CONCLUSION

This is the first study to demonstrate the frequency of symptomatic and clinical DE in a tertiary care ophthalmology center in Mexico. The frequency of DE ranged from 30% using a symptomatic definition to 94% using objective measures. Different risk factors were found for different aspects of DE, suggesting differing underlying pathophysiologies behind different DE subtypes.

Longitudinal changes in Langerhans cell density of the cornea and conjunctiva in contact lens-induced dry eye

BACKGROUND

The aim was to determine longitudinal changes in Langerhans cell density (LCD) in the human cornea and conjunctiva during asymptomatic and symptomatic contact lens wear.

METHODS

Twenty-five participants with contact lens-induced dry eye (CLIDE) and 35 without CLIDE (NO-CLIDE), diagnosed using a range of symptom questionnaires and objective tests (tear film break up, cotton thread tear test and corneal staining) were enrolled. The central cornea and nasal bulbar conjunctiva were examined using a Heidelberg laser scanning confocal microscope at baseline and following one, four and 24 weeks wear of daily disposable hydrogel contact lenses. Twenty-three non-contact lens-wearing controls were also examined. Langerhans cells were counted manually from randomly selected images.

RESULTS

In the cornea, mean and standard error of the mean LCD was greater after one week of lens wear in CLIDE (55 ± 7 cells/mm² ) versus NO-CLIDE (43 ± 4 cells/mm² ) (p = 0.041) and controls (27 ± 4 cells/mm² ) (p < 0.001). LCD was also greater in NO-CLIDE versus controls (p = 0.010). At week 4, LCD was greater in CLIDE (41 ± 6 cells/mm² ) versus controls (27 ± 4 cells/mm² ) (p = 0.004). There were no other significant differences between groups at weeks four or 24. In the conjunctiva, LCD was greater after one week of lens wear in CLIDE (17 ± 1 cells/mm² ) (p = 0.003) and NO-CLIDE (17 ± 3 cells/mm² ) (p = 0.001) versus controls (7 ± 1 cells/mm² ). There were no significant differences between groups at weeks four or 24.

CONCLUSIONS

The initial transient increase in corneal and conjunctival LCD in CLIDE (versus NO-CLIDE) suggests an inflammatory component in the aetiology of this condition.

Corneal Mechanical Thresholds Negatively Associate With Dry Eye and Ocular Pain Symptoms

PURPOSE

To examine associations between corneal mechanical thresholds and metrics of dry eye.

METHODS

This was a cross-sectional study of individuals seen in the Miami Veterans Affairs eye clinic. The evaluation consisted of questionnaires regarding dry eye symptoms and ocular pain, corneal mechanical detection and pain thresholds, and a comprehensive ocular surface examination. The main outcome measures were correlations between corneal thresholds and signs and symptoms of dry eye and ocular pain.

RESULTS

A total of 129 subjects participated in the study (mean age 64 ± 10 years). Mechanical detection and pain thresholds on the cornea correlated with age (Spearman's ρ = 0.26, 0.23, respectively; both P < 0.05), implying decreased corneal sensitivity with age. Dry eye symptom severity scores and Neuropathic Pain Symptom Inventory (modified for the eye) scores negatively correlated with corneal detection and pain thresholds (range, r = -0.13 to -0.27, P < 0.05 for values between -0.18 and -0.27), suggesting increased corneal sensitivity in those with more severe ocular complaints. Ocular signs, on the other hand, correlated poorly and nonsignificantly with mechanical detection and pain thresholds on the cornea. A multivariable linear regression model found that both posttraumatic stress disorder (PTSD) score (β = 0.21, SE = 0.03) and corneal pain threshold (β = -0.03, SE = 0.01) were significantly associated with self-reported evoked eye pain (pain to wind, light, temperature) and explained approximately 32% of measurement variability (R = 0.57).

CONCLUSIONS

Mechanical detection and pain thresholds measured on the cornea are correlated with dry eye symptoms and ocular pain. This suggests hypersensitivity within the corneal somatosensory pathways in patients with greater dry eye and ocular pain complaints.

The influence of rigid gas permeable lens wear on the concentrations of dinucleotides in tears and the effect on dry eye signs and symptoms in keratoconus

PURPOSE

To evaluate the signs and symptoms of dry eye and dinucleotide secretion in tears of keratoconus patients (KC) and the potential effect of rigid gas permeable (RGP) contact lens wear.

METHODS

Twenty-three KC patients and forty control subjects were enrolled in this study. Signs of dry eye including tear volume, tear stability and corneal staining along with symptoms were assessed using the McMonnies questionnaire. Tears were collected using Schirmer strips, and dinucleotide concentrations in collected tears measured using high pressure liquid chromatography. Values obtained in KC and controls were compared. The effect of contact lens wear in KC was also assessed.

RESULTS

KC eyes showed a significantly lower tear volume compared to controls, shorter tear break up time (TBUT), higher corneal staining and higher McMonnies dry eye questionnaire scores (p<0.05). When compared with non-wearers, KC contact lens wearers showed significantly higher symptoms, lower Schirmer and TBUT values (p<0.05). Concentration of Ap4A (0.695±0.304μM vs. 0.185±0.178μM) and Ap5A (0.132±0.128μM vs. 0.045±0.036μM) were higher in KC compared to controls (p<0.001) and only Ap4A was statistically higher in RGP wearers compared to non-wearers (0.794±0.478μM vs. 0.417±0.313μM) (p<0.05).

CONCLUSION

Signs and symptoms of dry eye as well as concentrations of Ap4A and Ap5A were markedly increased in KC patients compared to controls. Moreover, Ap4A and symptoms of dry eye were statistically higher in RGP wearers compared to non-wearers. This seems to indicate that factors such as RGP contact lens wear might exacerbate the clinical condition of dry eye.

Patients with more severe symptoms of neuropathic ocular pain report more frequent and severe chronic overlapping pain conditions and psychiatric disease

OBJECTIVE

To study chronic pain and mental health profiles in patients with dry eye (DE) symptoms, comparing those with high and low levels of neuropathic ocular pain (NOP) complaints.

DESIGN

Cross-sectional study of 181 patients with DE symptoms (dry eye questionnaire score ≥6) seen in the Miami Veterans Affairs eye clinic. An evaluation was performed consisting of questionnaires regarding DE symptoms, NOP complaints (burning, sensitivity to wind, light and cold/hot temperatures) and pain elsewhere in the body (non-ocular). This was followed by a comprehensive ocular surface examination. The patients' comorbidities, medications, mental health (depression and post-traumatic stress disorder) and quality-of-life indices were also obtained. Patients were classified using cluster analysis into either the 'high NOP' or 'low NOP' group. Subsequent analyses were performed to examine differences in ocular and non-ocular parameters between these two groups.

RESULTS

Despite similar ocular surface findings, patients in the high NOP group had very different systemic (non-ocular) profiles with higher overall pain intensity ratings, higher frequency of comorbid chronic centralised pain conditions, lower quality-of-life indices and more abnormal mental health scores than those in the low NOP group.

CONCLUSIONS

Consistent with a chronic overlapping pain condition, patients with DE disease with more severe NOP symptoms report more frequent and severe non-ocular functional comorbid pain disorders.

Prevalence and associated factors of dry eye: Our experience in patients above 40 years of age at a Tertiary Care Center

Context:

Dry eye is a very common as well as under-diagnosed ocular disorder. It is not only troublesome in terms of its symptoms but also imposes a great financial burden.

Aims:

To determine the prevalence of dry eye in ophthalmology out-patients at a Tertiary Care Hospital and its association with various clinico-epidemiological factors.

Settings and Design:

A hospital-based study at a Tertiary Care Center was conducted including 400 out-patients of age 40 years and above.

Materials and Methods:

Patients were consecutively selected and underwent a routine ophthalmological examination along with tear film break-up time (TBUT) as a screening tool for detecting the presence of dry eye.

Statistical Analysis:

We performed a descriptive, univariate and multivariable logistic regression analysis to calculate odds ratios and 95% confidence interval.

Results:

The mean age of the study population was 58.6 years. The overall prevalence of dry eye was found to be 54.3%. An association was found between dry eye prevalence and outdoor workers, participants working indoor using air conditioners, housewives, diabetics, patients who have undergone previous ocular surgery and those with meibomian gland dysfunction.

Conclusions:

Dry eye is a very common condition with a high prevalence among the elderly. We recommend the screening of all out-patients by TBUT, which is a simple test to perform and examination of lids for meibomian gland disease, which if present can be treated. Further studies are needed to establish uniform diagnostic criteria for dry eye, which will help to get more concrete prevalence data, as well as its etiological factors.

Assessment of conjunctival goblet cell density using laser scanning confocal microscopy versus impression cytology

PURPOSE

To determine the association between conjunctival goblet cell density (GCD) assessed using in vivo laser scanning confocal microscopy and conjunctival impression cytology in a healthy population.

METHODS

Ninety (90) healthy participants undertook a validated 5-item dry eye questionnaire, non-invasive tear film break-up time measurement, ocular surface fluorescein staining and phenol red thread test. These tests where undertaken to diagnose and exclude participants with dry eye. The nasal bulbar conjunctiva was imaged using laser scanning confocal microscopy (LSCM). Conjunctival impression cytology (CIC) was performed in the same region a few minutes later. Conjunctival goblet cell density was calculated as cells/mm(2).

RESULTS

There was a strong positive correlation of conjunctival GCD between LSCM and CIC (ρ=0.66). Conjunctival goblet cell density was 475±41 cells/mm(2) and 466±51 cells/mm(2) measured by LSCM and CIC, respectively.

CONCLUSIONS

The strong association between in vivo and in vitro cellular analysis for measuring conjunctival GCD suggests that the more invasive CIC can be replaced by the less invasive LSCM in research and clinical practice.

Dry Eye Profiles in Patients with a Positive Elevated Surface Matrix Metalloproteinase 9 Point-of-Care Test Versus Negative Patients

PURPOSE

To compare dry eye (DE) symptoms and signs in subjects who tested positive versus those who tested negative for ocular surface matrix metalloproteinase 9 (MMP-9) using the InflammaDry point-of-care test (RPS, Sarasota, FL).

METHODS

In this cross-sectional study, individuals seen in the Miami Veterans Affairs eye clinic with DE symptoms, as evidenced by DE questionnaire 5 (DEQ5) ≥6, were given standardized questionnaires to assess DE symptoms and ocular and non-ocular pain complaints. Also, a complete evaluation was conducted to measure ocular surface signs of DE. MMP-9 testing was performed using the InflammaDry once in each eye, per the manufacturer's instructions. The main outcome measure was a comparison of DE symptoms and signs in MMP-9 positive versus negative subjects.

RESULTS

Of 128 subjects, 50 (39%) were positive for MMP-9 for InflammaDry testing in either eye. No statistically significant differences in mental health indices, DE symptoms, or ocular surface signs were seen in subjects based on MMP-9 status.

CONCLUSION

In our population, there was no difference in the DE profile by both symptoms and signs between those testing positive versus negative for MMP-9 on the ocular surface. This suggests that clinical exam alone cannot predict patients with clinically significant inflammation.

Making the diagnosis of Sjögren's syndrome in patients with dry eye

Sjögren’s syndrome (SS) is a chronic and progressive systemic autoimmune disease that often presents initially with symptoms of dry eye and dry mouth. Symptoms are often nonspecific and develop gradually, making diagnosis difficult. Patients with dry eye complaints warrant a step-wise evaluation for possible SS. Initial evaluation requires establishment of a dry eye diagnosis using a combination of patient questionnaires and objective ocular tests, including inflammatory biomarker testing. Additional work-up using the Schirmer test and tear film break-up time can differentiate between aqueous-deficient dry eye (ADDE) and evaporative dry eye. The presence of ADDE should trigger further work-up to differentiate between SS-ADDE and non-SS-ADDE. There are numerous non-ocular manifestations of SS, and monitoring for SS-related comorbid findings can aid in diagnosis, ideally in collaboration with a rheumatologist. The clinical work-up of SS can involve a variety of tests, including tear function tests, serological tests for autoantibody biomarkers, minor salivary gland and lacrimal gland biopsies. Examination of classic SS biomarkers (SS-A/Ro, SS-B/La, antinuclear antibody, and rheumatoid factor) is a convenient and non-invasive way of evaluating patients for the presence of SS, even years prior to confirmed diagnosis, although not all SS patients will test positive, particularly those with early disease. Recently, newer biomarkers have been identified, including autoantibodies to salivary gland protein-1, parotid secretory protein, and carbonic anhydrase VI, and may allow for earlier diagnosis of SS. A diagnostic test kit is commercially available (Sjö^®), incorporating these new biomarkers along with the classic autoantibodies. This advanced test has been shown to identify SS patients who previously tested negative against traditional biomarkers only. All patients with clinically significant ADDE should be considered for serological assessment for SS, given the availability of new serological diagnostic tests and the potentially serious consequences of missing the diagnosis.

Burning Eye Syndrome: Do Neuropathic Pain Mechanisms Underlie Chronic Dry Eye?

OBJECTIVE

Dry eye is a multi-factorial disorder that manifests with painful ocular symptoms and visual disturbances, which can only be partly attributed to tear dysfunction. This disorder may also involve neuroplasticity in response to neuronal injury. This review will emphasize the key characteristics of dry eye pain and its pathologic mechanisms, making the argument that a subset of dry eye represents a neuropathic pain disorder of the eye, more appropriately called "burning eye syndrome."

METHODS

A literature review was conducted using a PubMed search focusing on dry eye, corneal nociception, and neuropathic pain. Articles were reviewed and those discussing clinical course, pathophysiology, and neuronal regulation of chronic ocular pain as related to dry eye were summarized.

RESULTS

We found that there is a discordance between ocular pain and dryness on the ocular surface. Although tear dysfunction may be one of the initial insults, its persistence may be associated with repeated ocular sensory nerve injury leading to an acute-to-chronic pain transition associated with neuropathologic changes (peripheral and central sensitization), neuronal dysfunction, and spontaneous ocular pain.

CONCLUSION

Dry eye is becoming a major health concern due to its increasing incidence, significant morbidity, and economic burden. Recent evidence suggests that a subset of dry eye may be better represented as a chronic neuropathic pain disorder due to its features of dysesthesia, spontaneous pain, allodynia, and hyperalgesia. Future therapies targeted at the underlying neuroplasticity may yield improved efficacy for patients with this subset of dry eye, which we term "burning eye syndrome."

Incomplete response to artificial tears is associated with features of neuropathic ocular pain

AIMS

Artificial tears are first-line therapy for patients with dry eye symptoms. It is not known, however, which patient factors associate with a positive response to therapy. The purpose of this study was to evaluate whether certain ocular and systemic findings are associated with a differential subjective response to artificial tears.

METHODS

Cross-sectional study of 118 individuals reporting artificial tears use (hypromellose 0.4%) to treat dry eye-associated ocular pain. An evaluation was performed to assess dry eye symptoms (via the dry eye questionnaire 5 and ocular surface disease index), ocular and systemic (non-ocular) pain complaints and ocular signs (tear osmolarity, tear breakup time, corneal staining, Schirmer testing with anaesthesia, and eyelid and meibomian gland assessment). The main outcome measures were factors associated with differential subjective response to artificial tears.

RESULTS

By self-report, 23 patients reported no improvement, 73 partial improvement and 22 complete improvement in ocular pain with artificial tears. Patients who reported no or partial improvement in pain with artificial tears reported higher levels of hot-burning ocular pain and sensitivity to wind compared with those with complete improvement. Patients were also asked to rate the intensity of systemic pain elsewhere in the body (other than the eye). Patients who reported no or incomplete improvement with artificial tears had higher systemic pain scores compared with those with complete improvement.

CONCLUSIONS

Both ocular and systemic (non-ocular) pain complaints are associated with a differential subjective response to artificial tears.

The Effects of Increasing Ocular Surface Stimulation on Blinking and Tear Secretion

PURPOSE

To investigate the effect of varying levels of ocular surface stimulation on the timing and amplitude of the blink and tear secretion.

METHODS

Following instillation of fluorescein dye, increasing levels of air flow were directed toward the central corneas of 10 healthy subjects. Interblink interval (IBI), tear meniscus height (TMH), and fluorescence intensity were measured simultaneously. Because blinking can obscure changes in TMH, we developed novel measures of tear secretion by calculating tear meniscus fluorescein concentration (TMFC) from intensity using a mathematical model. The change of TMH and TMFC over trials and the slope of the TMFC within each IBI (IBI-TTR) were further calculated.

RESULTS

The mean IBI was decreased by 8.08 ± 8.54 seconds from baseline to maximum air stimulation. The TMH increase was highly variable (0.41 ± 0.39 mm) among subjects, compared to the fluorescence tear turnover metrics: decrease in TMFC of 2.84 ± 0.98 natural logarithm or ln(%) and IBI-TTR of 0.065 ± 0.032 ln(%)/sec. Ocular surface stimulation was highly correlated with the TMFC and IBI-TTR, but less so with TMH (Pearson's r = 0.71, 0.69, and 0.40, P < 0.01, respectively). Blinking and tearing were significantly correlated with each other (Pearson's r = 0.56, P < 0.01), but tearing lagged behind by an average of 6.54 ± 4.07 seconds.

CONCLUSIONS

Blinking and tearing share a common origin with sensory stimulation at the ocular surface. Both showed a dose-response increase with surface stimulation and were correlated with each other. These methods can potentially be used to understand alterations in ocular surface sensory function and associated protective responses in dry eye and other disorders of the ocular surface.

Prevalence, risk factors, and morbidity of eye lid laxity in a veteran population

PURPOSE

The aim of this study was to study prevalence, risk factors, and morbidity of eyelid laxity in a veteran population.

METHODS

This prospective cross-sectional study with a retrospective chart review included 150 subjects evaluated from either an outpatient eye clinic or a geriatric clinic at the Miami Veterans Affairs Hospital from June through August 2013. Clinical data were gathered from a questionnaire and a computerized medical record system including demographics, medical history, and ocular irritation history. Upper and lower eyelid laxity was clinically graded. Main outcome measures were prevalence of eyelid laxity, risk factors for its presence, and its correlation to ocular surface symptoms.

RESULTS

Fifty-four percent of participants (n = 81) had laxity (grade 1 or higher) in either upper and/or lower eyelids. Risk factors for eyelid laxity in our population included older age, higher body mass index, and a diagnosis of sleep apnea. Patients with any eyelid laxity (grade 1 or more in any eyelid) had a 2.23-fold risk of severe ocular surface symptoms (score of 12 or higher on the dry eye questionnaire 5) compared with those without laxity (95% confidence interval, 1.15-4.31; P = 0.017), and this was primarily driven by the presence of upper eyelid laxity.

CONCLUSIONS

We found high prevalence of eyelid laxity in our population, and its presence was associated with significant ocular surface morbidity. This study reinforces the need to incorporate dynamic eyelid testing into ophthalmic examination in patients with ocular surface discomfort.

Chronic migraine is associated with reduced corneal nerve fiber density and symptoms of dry eye

BACKGROUND

We used in vivo corneal confocal microscopy to investigate structural differences in the sub-basal corneal nerve plexus in chronic migraine patients and a normal population. We used a validated questionnaire and tests of lacrimal function to determine the prevalence of dry eye in the same group of chronic migraine patients. Activation of the trigeminal system is involved in migraine. Corneal nociceptive sensation is mediated by trigeminal axons that synapse in the gasserian ganglion and the brainstem, and serve nociceptive, protective, and trophic functions. Noninvasive imaging of the corneal sub-basal nerve plexus is possible with in vivo corneal confocal microscopy.

METHODS

For this case-control study, we recruited chronic migraine patients and compared them with a sex- and age-similar group of control subjects. Patients with peripheral neuropathy, a disease known to be associated with a peripheral neuropathy, or prior corneal or intraocular surgery were excluded. Participants underwent in vivo corneal confocal microscopy using a Heidelberg Retinal Tomography III confocal microscope with a Rostock Cornea Module. Nerve fiber length, nerve branch density, nerve fiber density, and tortuosity coefficient were measured using established methodologies. Migraine participants underwent testing of basal tear production with proparacaine, corneal sensitivity assessment with a cotton-tip applicator, measurement of tear break-up time, and completion of a validated dry eye questionnaire.

RESULTS

A total of 19 chronic migraine patients and 30 control participants completed the study. There were no significant differences in age or sex. Nerve fiber density was significantly lower in migraine patients compared with controls (48.4 ± 23.5 vs. 71.0 ± 15.0 fibers/mm2 , P < .001). Nerve fiber length was decreased in the chronic migraine group compared with the control group, but this difference was not statistically significant (21.5 ± 11.8 vs. 26.8 ± 5.9 mm/mm2, P < .084). Nerve branch density was similar in the two groups (114.0 ± 92.4 vs. 118.1 ± 55.9 branches/mm2 , P < .864). Tortuosity coefficient and log tortuosity coefficient also were similar in the chronic migraine and control groups. All migraine subjects had symptoms consistent with a diagnosis of dry eye syndrome.

CONCLUSIONS

We found that in the sample used in this study, the presence of structural changes in nociceptive corneal axons lends further support to the hypothesis that the trigeminal system plays a critical role in the pathogenesis of migraine. In vivo corneal confocal microscopy holds promise as a biomarker for future migraine research as well as for studies examining alterations of corneal innervation. Dry eye symptoms appear to be extremely prevalent in this population. The interrelationships between migraine, corneal nerve architecture, and dry eye will be the subject of future investigations.

Dry eye specific quality of life in veterans using glaucoma drops

PURPOSE

To evaluate the frequency of ocular surface symptoms and their potential impact on dry eye specific quality of life (QoL) in patients using versus not using glaucoma medications.

MATERIAL AND METHODS

The study was a single-center, cross-sectional survey of patients seen at the Miami Veterans Affairs (VA) ophthalmology and optometry clinics from June to August, 2010. Patients were invited to complete the Dry Eye Questionnaire 5 (DEQ5) and the Impact of Dry Eye on Everyday Life (IDEEL) at their visit. Of 1348 patients seen in the Miami VA eye clinics during this three-month period, 467 patients completed the DEQ5 and 391 responded to both questionnaires. Outcome measures comprised ocular surface symptoms and their impact on dry eye specific QoL in patients using versus not using glaucoma drops.

RESULTS

An increasing number of glaucoma drops was significantly associated with an increased percentage of severe dry eye symptoms: no medications, 25% (n=89/353); 1 or 2 medications, 27% (n=17/62); 3 or more medications, 40% (n=21/52); p=0.03 (Armitage's test for linear-trend in proportions). There was an association between increasing number of drops and decreasing emotional well-being scores (linear p<0.001; quadratic p=0.029). Black patients had higher dry eye symptoms and lower emotional QoL scores compared to white patients at every level of medication use.

CONCLUSION

An increasing number of glaucoma medications were associated with an increased frequency of severe dry eye symptoms and decreased emotional QoL. Additionally, dry eye specific emotional QoL was more severely affected in black versus white patients.

Neuropathic ocular pain: an important yet underevaluated feature of dry eye

Dry eye has gained recognition as a public health problem given its prevalence, morbidity, and cost implications. Dry eye can have a variety of symptoms including blurred vision, irritation, and ocular pain. Within dry eye-associated ocular pain, some patients report transient pain whereas others complain of chronic pain. In this review, we will summarize the evidence that chronicity is more likely to occur in patients with dysfunction in their ocular sensory apparatus (ie, neuropathic ocular pain). Clinical evidence of dysfunction includes the presence of spontaneous dysesthesias, allodynia, hyperalgesia, and corneal nerve morphologic and functional abnormalities. Both peripheral and central sensitizations likely play a role in generating the noted clinical characteristics. We will further discuss how evaluating for neuropathic ocular pain may affect the treatment of dry eye-associated chronic pain.

Effect of a Mediterranean dietary pattern and vitamin D levels on Dry Eye syndrome

PURPOSE

The aim of this study was to evaluate the association between a Mediterranean dietary pattern (MeDi) and Vitamin D levels on dry eye syndrome (DES).

METHODS

This was a cross-sectional study. Male patients seen in the Miami Veterans Affairs eye clinic with normal eyelid, corneal, and conjunctival anatomy were recruited to participate in the study. The patients filled out the 2005 Block Food Frequency Questionnaire and the Dry Eye Questionnaire 5 and underwent measurement of tear film parameters. The serum level of 25-hydroxy vitamin D was also measured. The main outcome measures included the association among MeDi, Vitamin D levels, and DES.

RESULTS

Two hundred forty-seven men underwent DES testing. The mean patient age was 69 years (range, 55-95). Using latent class analysis to categorize the presence or absence of disease and quantify its severity, we found that adherence to the MeDi was positively associated with the risk of having DES (odd ratio 1.25, 95% confidence interval, 1.06-1.47, P = 0.007) and with increasing disease severity. Vitamin D levels were not significantly associated with the presence or severity of disease. However, higher levels of vitamin D were associated with decreased DES symptoms, with a -1.24 decrease in median Dry Eye Questionnaire 5 score for every 10-U increase in Vitamin D levels (P = 0.01).

CONCLUSIONS

Adherence to the MeDi was not associated with a beneficial effect on DES. Higher vitamin D levels had a small but favorable effect on DES symptoms.

Androgen deficiency and dry eye syndrome in the aging male

PURPOSE

To evaluate the relationship between androgen levels and subjective and objective measures of dry eye syndrome (DES).

METHODS

A total of 263 male patients from the Miami Veterans Affairs Medical Center eye clinic aged ≥50 were recruited for this prospective cross-sectional study. Patients completed Dry Eye Questionnaire 5, underwent tear film evaluation, and had serum androgen levels measured. The correlations between androgen levels, DES composite scores, DES symptoms, and global, lipid, and aqueous tear film parameters were evaluated.

RESULTS

Two hundred sixty-three patients with a mean age of 69 (50-95) were examined. There was no linear association between composite DES scores (generated using latent class analysis) and androgen levels. However, eyes with high DES scores (0.95-1.0) had higher levels of sex hormone-binding globulin (P = 0.03) and lower levels of dehydroepiandrosterone sulfate (DHEAS) (P = 0.02), androstenedione (A) (P = 0.02), and androstane-3α,17β-diol glucuronide (P = 0.03) compared to eyes with intermediate (0.05-0.95) or low (0-0.05) scores. There were no strong correlations between tear film measures and androgen levels. Regarding global parameters, a weak inverse correlation was found between corneal staining and A (r = -0.17, P = 0.009). For lipid parameters, a weak correlation existed between tear breakup time (TBUT) and A (r = 0.15, P = 0.02). When considering aqueous and lipid deficiency independently, the association between TBUT and A existed only with aqueous tear deficiency (r = 0.66, P = 0.002). Regarding aqueous parameters, a weak correlation existed between Schirmer test and DHEAS (r = 0.13, P = 0.047) and A (r = 0.21, P = 0.001).

CONCLUSIONS

There was a weak correlation between higher levels of androstenedione and healthier global, lipid, and aqueous tear film parameters.

Correlation of tear osmolarity and dry eye symptoms in convention attendees

PURPOSE

To assess the correlation between tear osmolarity readings and symptoms of dry eye in a nonclinical convenience sample and to determine how well symptoms and osmolarity correlate with the self-assessment of dry eye.

METHODS

Two hundred forty-nine attendees in the exhibit hall at an optometric educational meeting agreed to participate in a dry eye study. Contact lens wearers were excluded. Volunteers supplied demographic information and completed a 5-item Dry Eye Questionnaire (DEQ-5) and answered the question "Do you think you have dry eye" with a yes or no response. Osmolarity testing was done using the TearLab instrument on the right eye, then on the left eye. Pearson correlation analyses were performed to determine the relationship between variables.

RESULTS

There was no correlation between DEQ-5 scores and average tear osmolarity (correlation coefficient, 0.02) and highest osmolarity (correlation coefficient, 0.03). The mean DEQ-5 score was significantly higher among subjects who self-reported dry eye (mean, 11.3; p < 0.0001) compared with those who did not (mean, 5.4; p < 0.0001). No differences were observed between the yes and no self-reported dry eye groups and average osmolarity (p = 0.23) and highest osmolarity (p = 0.14).

CONCLUSIONS

In this nonclinical population, there was no significant correlation between tear osmolarity and ocular symptoms as reported or between tear osmolarity and the self-assessment of dry eye.

The effects of increasing ocular surface stimulation on blinking and sensation

PURPOSE

The purpose of this study was to determine how increasing ocular surface stimulation affected blinking and sensation, while controlling task concentration.

METHODS

Ten healthy subjects concentrated on a task while a custom pneumatic device generated air flow toward the central cornea. Six flow rates (FRs) were randomly presented three times each and subjects used visual analog scales to record their sensory responses. The interblink interval (IBI) and the FR were recorded simultaneously and the IBI, sensory response, and corresponding FR were determined for each trial. The FR associated with a statistically significant decrease in IBI, the blink increase threshold (BIT), was calculated for each subject.

RESULTS

Both the mean and SD of IBI were decreased with increasing stimulation, from 5.69 ± 3.96 seconds at baseline to 1.02 ± 0.37 seconds at maximum stimulation. The average BIT was 129 ± 20 mL/min flow rate with an IBI of 2.33 ± 1.10 seconds (permutation test, P < 0.001). After log transformation, there was a significant linear function between increasing FR and decreasing IBI within each subject (Pearson's r ≤ -0.859, P < 0.05). The IBI was highly correlated with wateriness, discomfort, and cooling ratings (Pearson's r ≤ -0.606, P < 0.001).

CONCLUSIONS

There was a dose-response-like relationship between increased surface stimulation and blinking in healthy subjects, presumably for protection of the ocular surface. The blink response was highly correlated with ocular surface sensation, which is not surprising given their common origins. The BIT, a novel metric, may provide an additional end point for studies on dry eye or other conditions.

Impact of dry eye on reading in a population-based sample of the elderly: the Salisbury Eye Evaluation

BACKGROUND/AIMS

People with dry eye often complain of difficulty reading, but this perceived deficit has not been appropriately quantified. The purpose of this study is to determine if dry eye is associated with measurable reading deficits.

METHODS

A cross-sectional study of 1981 participants in the Salisbury Eye Evaluation, a population-based study of the elderly. Dry eye symptoms were identified by questionnaire and clinically significant dry eye was defined as the presence of dry eye symptoms and positive Schirmer testing or ocular surface staining in either eye. Spoken reading speed was measured using short text passages. Subjects self-reported if they did not read or had difficulty reading newsprint.

RESULTS

13.8% of subjects (274/1981) had dry eye symptoms and 3.1% (62/1981) had clinically significant dry eye. There was no difference in reading speed between subjects with dry eye symptoms or clinically significant dry eye and their controls (p=0.99 and 0.78, respectively) in multivariable models. Compared with asymptomatic subjects, however, subjects with dry eye symptoms were more likely to report reading difficulty (OR=1.7, 95% CI 1.3 to 2.4, p<0.01) and not reading newsprint (OR=1.9, 95% CI 1.0 to 3.6, p=0.04). Similarly, subjects with clinically significant dry eye were more likely to report difficulty reading newsprint (OR=2.5, 95% CI 1.4 to 4.5, p<0.01) or not reading newsprint at all (OR=4.1, 95% CI 1.6 to 10.7, p<0.01) as compared with subjects without dry eye signs or symptoms.

CONCLUSIONS

Dry eye did not significantly affect reading speed but was associated with self-reported reading difficulty and avoidance of newspaper reading in this elderly population-based sample.

A preliminary investigation into the effects of ocular lubricants on higher order aberrations in normal and dry eye subjects

PURPOSE

To study the effects of ocular lubricants on higher order aberrations in normal and self-diagnosed dry eyes.

METHODS

Unpreserved hypromellose drops, Tears Again™ liposome spray and a combination of both were administered to the right eye of 24 normal and 24 dry eye subjects following classification according to a 5 point questionnaire. Total ocular higher order aberrations, coma, spherical aberration and Strehl ratios for higher order aberrations were measured using the Nidek OPD-Scan III (Nidek Technologies, Gamagori, Japan) at baseline, immediately after application and after 60 min. The aberration data were analyzed over a 5mm natural pupil using Zernike polynomials. Each intervention was assessed on a separate day and comfort levels were recorded before and after application. Corneal staining was assessed and product preference recorded after the final measurement for each intervention.

RESULTS

Hypromellose drops caused an increase in total higher order aberrations (p=<0.01 in normal and dry eyes) and a reduction in Strehl ratio (normal eyes: p=<0.01, dry eyes p=0.01) immediately after instillation. There were no significant differences between normal and self-diagnosed dry eyes for response to intervention and no improvement in visual quality or reduction in higher order aberrations after 60 min. Differences in comfort levels failed to reach statistical significance.

CONCLUSION

Combining treatments does not offer any benefit over individual treatments in self-diagnosed dry eyes and no individual intervention reached statistical significance. Symptomatic subjects with dry eye and no corneal staining reported an improvement in comfort after using lubricants.

Comparison of two methods for composite score generation in dry eye syndrome

PURPOSE

To compare two methods of composite score generation in dry eye syndrome (DES).

METHODS

Male patients seen in the Miami Veterans Affairs eye clinic with normal eyelid, corneal, and conjunctival anatomy were recruited to participate in the study. Patients filled out the Dry Eye Questionnaire 5 (DEQ5) and underwent measurement of tear film parameters. DES severity scores were generated by independent component analysis (ICA) and latent class analysis (LCA).

RESULTS

A total of 247 men were included in the study. Mean age was 69 years (SD 9). Using ICA analysis, osmolarity was found to carry the largest weight, followed by eyelid vascularity and meibomian orifice plugging. Conjunctival injection and tear breakup time (TBUT) carried the lowest weights. Using LCA analysis, TBUT was found to be best at discriminating healthy from diseased eyes, followed closely by Schirmer's test. DEQ5, eyelid vascularity, and conjunctival injection were the poorest at discrimination. The adjusted correlation coefficient between the two generated composite scores was 0.63, indicating that the shared variance was less than 40%.

CONCLUSIONS

Both ICA and LCA produced composite scores for dry eye severity, with weak to moderate agreement; however, agreement for the relative importance of single diagnostic tests was poor between the two methods.

The effects of mild ocular surface stimulation and concentration on spontaneous blink parameters

PURPOSE

This exploratory, pilot study compared the effects of concentrating on a visual task and a very mild ocular surface air stimulus on multiple blink parameters.

METHODS

Ten subjects participated in this study. There were two visits, one with an ocular surface air stimulus (AS) and one without (NS). The AS was set at a level barely perceptible by subjects (approximately 0.6 m/s at the eye). At each visit, subjects performed a high-concentration (HC) and low-concentration (LC) task. Blinking was tracked and tear-film breakup (TBU) was monitored simultaneously to measure blink parameters, including the interblink interval (IBI), blink amplitude, duration, maximum velocity and TBU before and after each blink.

RESULTS

During the HC tasks, IBI was significantly higher and blink duration was lower (repeated measures ANOVA, p < 0.05) than the LC tasks. The IBI in the AS-LC condition was significantly lower and less variable than in the NS-HC condition, whereas blink duration showed the opposite effect (Hotelling T² test, p < 0.005). There was high individual variation in correlations between blink amplitude and maximum velocity. The area of TBU was not significantly correlated with any blink parameter.

CONCLUSIONS

The lack of correlation between TBU and blinking suggests that many blinks are stimulated by internal controls, rather than direct stimulation of the ocular surface by TBU. This pilot study suggests that even very mild ocular surface stimulation produces opposite effects on the timing and duration of the blink, when compared to concentrating on a visual task. The HC task tends to decrease blink frequency and duration, presumably to minimize interruption by the eyelids, whereas mild ocular surface AS increased blink frequency and duration, most likely to increase protection of the ocular surface.

Quantitative analysis of tear film fluorescence and discomfort during tear film instability and thinning

PURPOSE

The purpose of this study was to test the association between tear film fluorescence changes during tear break-up (TBU) or thinning and the concurrent ocular sensory response.

METHODS

Sixteen subjects kept one eye open as long as possible (MBI), indicated their discomfort level continuously, and rated ocular sensations of irritation, stinging, burning, pricking, and cooling using visual analog scales (VAS). Fluorescence of the tear film was quantified by a pixel-based analysis of the median pixel intensity (PI), TBU, and percentage of dark pixels (DarkPix) over time. A cutoff of 5% TBU was used to divide subjects into either break-up (BU) or minimal break-up (BUmin) groups.

RESULTS

Tear film fluorescence decreased (median PI) and the percentage of TBU and DarkPix increased in all trials, with the rate significantly greater in the BU than the BUmin group (Mann-Whitney U test, P < 0.05). The rate of increasing discomfort during trials was highly correlated with the rate of decrease in median PI and developing TBU (Spearman's, r ≥ 0.70). Significant correlations were found between corneal fluorescence, MBI, and sensory measures.

CONCLUSIONS

Concentration quenching of fluorescein dye with tear film thinning best explains decreasing tear film fluorescence during trials. This was highly correlated with increasing ocular discomfort, suggesting that both tear film thinning and TBU stimulate underlying corneal nerves, although TBU produced more rapid stimulation. Slow increases in tear film hyperosmolarity may cause the gradual increase in discomfort during slow tear film thinning, whereas the sharp increases in discomfort during TBU suggest a more complex stimulus.

Ocular surface parameters in older male veterans

PURPOSE

To characterize ocular surface discomfort and tear film parameters in a veteran population.

METHODS

Male patients seen in the Miami Veterans Affairs eye clinic aged 50 years or older were recruited to participate in the study. All patients had normal eyelid, corneal, and conjunctival anatomy. Patients filled out the Dry Eye Questionnaire 5 (DEQ5) and underwent measurement of tear film parameters. The main outcome measures were the frequency of ocular surface symptoms and the correlation between symptoms and global, aqueous, and meibomian gland parameters.

RESULTS

A total of 263 men participated in the study; 48% had DES based on the presence of severe symptoms. Many men had objective abnormalities in tear function measurements. Using Schirmer information, lid plugging, and meibomian quality to define objective DES, 176 patients (68%) had one or more abnormalities. Of these, 22 (8%) had aqueous tear deficiency, 124 (47%) lipid tear deficiency, and 30 (11%) a mixed pattern. When examining associations between individual clinical parameters and DEQ5 score, the only significant, but weak, correlations were with the global parameters conjunctival and corneal staining (r = 0.16) and TBUT (r = -0.15). Neither specific aqueous nor meibomian gland measurements were significantly correlated with the presence of symptoms. When considering all measured parameters in a regression model, 8% of the variability in symptoms was explained by the tear parameters.

CONCLUSIONS

We found that ocular surface symptoms were prevalent in our population. Measurement of standard tear film parameters could not explain the degree of symptoms. This study highlights the need for future research regarding the mechanisms behind ocular surface discomfort in patients with tear film disturbances.

Impact of dry eye syndrome on vision-related quality of life in a non-clinic-based general population

Background

Dry eye syndrome (DES) is a common ocular disorder occurring in general population. The purpose of this study is to evaluate the impact of DES on vision-related quality of life (QoL) in a non-clinic-based general population.

Methods

This population-based cross-sectional study enrolled subjects older than 40 years, who took part in an epidemiological study on dry eye in Sanle Community, Shanghai. Apart from the collection of sociodemographics, dry eye symptoms, and other clinical data, a Chinese version of the 25-item National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) was administered to all subjects. Comparisons of the NEI VFQ-25 subscale item scores and composite score were made among subgroups divided according to the presence of dry eye symptoms or signs. Multivariate regression analysis was performed to investigate the relationship between the clinical variables and the VFQ-25 composite score.

Results

A total of 229 participants were enrolled in the study, with an average age of (60.7 ±10.1) years old. Majority of these participants were female (59.8 %, 137/229). The total DES symptom scores (TDSS) in subjects either with definite DES or only with dry eye symptoms were significantly higher (F = 60.331, P < 0.001). The values of tear break-up time (TBUT) and Schirmer test were significantly lower in participants with DES and those with dry eye signs only (F = 55.158 and 40.778, P < 0.001). The composite score of the NEI VFQ-25 was significantly lower in subjects with DES (F = 4.901, P = 0.003). Moreover, the subscale scores of ocular pain and mental health were significantly lower in those with either DES or dry eye symptoms only (F = 10.962 and 7.362 respectively, both P < 0.001). The multiple regression analysis showed that the TDSS had a significant negative correlation with the VFQ-25 composite score as well as with the subscale score for ocular pain and mental health, even after the adjustment of all other factors (all P < 0.01).

Conclusions

The symptoms of dry eye are associated with an adverse impact on vision-related QoL in non-clinic-based general population, which is mainly represented as more ocular pain and discomfort, and impaired mental health as well. Apart from clinical examination, it is also important to refer to subjective symptoms and QoL scores when assessing the severity of DES.

Impact of ocular surface symptoms on quality of life in a United States veterans affairs population

PURPOSE

To evaluate the impact of ocular surface symptoms on quality of life in a veteran population receiving eye care services.

DESIGN

Cross-sectional survey study.

METHODS

setting: Miami Veterans Affairs Medical Center (VAMC). patient population: Patients seen at the eye clinic between June and August 2010 were asked to fill out the Dry Eye Questionnaire 5 (DEQ5) and the Impact of Dry Eye on Everyday Life (IDEEL) questionnaire. main outcome measures: Correlation between ocular surface symptoms and functionality.

RESULTS

Four hundred eighty-nine patients elected to fill out the DEQ5 questionnaire (36% response rate). The mean age of respondents was 66 years (standard deviation 12). Ninety-four percent were male; 62% were white and 37% were black. Using the DEQ5 as a surrogate measure of ocular surface symptoms, 65% of respondents reported at least mild ocular surface symptoms (DEQ5 ≥6) and 27% of them reported severe symptoms (DEQ5 ≥12). Black subjects had a 2-fold increased risk of severe symptoms compared to white subjects (odds ratio 2.06, 95% confidence interval 1.33-3.19). Several medications were associated with a significantly increased risk of severe symptoms, including glaucoma medications (1.7-fold increase), antidepressants (2.3-fold increase), and antihistamines (2.1-fold increase). There was an inverse correlation between DEQ5 and IDEEL scores with regard to ability to perform activities of daily living (n = 391, r = -0.54, P < .001), emotional well-being (n = 386, r = -0.63, P < .001), and the ability to work (n = 205, r = -0.57, P < .001). Fifty percent of patients with severe symptoms had documentation that their symptoms were addressed during the visit.

CONCLUSION

Severe ocular surface symptoms reduce the quality of life of Miami VAMC veterans. Eye care professionals should be vigilant in eliciting ocular surface complaints from their patients.

Appraisal of patient-reported outcome instruments available for randomized clinical trials in dry eye: revisiting the standards

Clinical signs in dry eye (DE) often underestimate the severity of the condition, correlating poorly with symptoms and the impact on patients' health-related quality of life (HRQL). Patient-reported outcome (PRO) questionnaires are therefore essential to accurately evaluate the health status of DE patients and the severity of their condition. A comprehensive evaluation of HRQL in addition to clinical signs and visual function is necessary to fully characterize the impact of DE on patients' health. Growing interest in PRO measures and their implementation in clinical trials has resulted in more formal guidance on the design and properties of these instruments. To be scientifically sound and accepted by regulatory authorities, an instrument's development process and its appropriateness for use in the target population, its psychometric properties and responsiveness must be described. To address the recent health authority guidance, this review discusses the design, development methodology, and performance of currently available PRO instruments for DE.