Optimum dry eye classification using questionnaire responses

Prevalence and Risk Factors for Symptomatic Dry Eye Disease Based on McMonnies Questionnaire Among Medical Students, Saudi Arabia; a Cross-Sectional Study

Purpose

Dry eye disease (DED) is a common ocular problem that worsens patients' quality of life. This study aimed to assess DED prevalence and risk factors among medical students at the University of Tabuk.

Patients and Methods

This is an analytical, cross-sectional, survey-based study. An online questionnaire was distributed by email to all medical students at the University of Tabuk. A self-administered McMonnies questionnaire was used in the assessment.

Results

We included 247 medical students who completed the questionnaire. Most participants were females (71.3%) and were <25 years old (85.8%). DED prevalence rate was 18.2% (95% CI=13.61% to 23.61%). Furthermore, DED was found to be significantly associated with the presence of irritation of eyes when waking up from sleep (OR=19.315), sleeping with partially opened eyes (OR=19.105), redness and irritation of the eyes when swimming in chlorinated fresh water (OR=7.863), and having prescription eyedrops or other dry eye treatments (OR=3.083).

Conclusion

Our study at the University of Tabuk found that 18.2% of medical students had dry eye disease and identified the associated risk factors. Early diagnosis and treatment are crucial to prevent complications due to the high prevalence of DED.

Improvement of Soft Contact Lens Wettability After the Instillation of Hyaluronic Acid Eye Drops

PURPOSE

To evaluate the effect of the topical instillation of hyaluronic acid eye drops with different viscosity on soft contact lens wettability and comfort.

METHODS

A randomized and participant-masked study was performed, involving 20 participants (25.4±2.6 years). One eye wore hydrogel (ocufilcon D) contact lenses, and another eye wore silicone-hydrogel (somofilcon A) contact lenses. The in vivo wettability tear film surface quality (TFSQ) index and comfort were measured before and after the instillation of different eye drops: saline solution (control) and 0.1%, 0.2%, and 0.3% hyaluronic acid.

RESULTS

Compared with saline solution, the instillation of 0.1%, 0.2%, and 0.3% hyaluronic acid improved the in vivo wettability of the hydrogel contact lenses by decreasing their TFSQ mean for 5, 10, and 30 min, respectively ( P <0.05). During silicone-hydrogel contact lens wear, the hyaluronic acid did not affect wettability because there were no changes in TFSQ mean ( P ≥0.05), but the 0.3% hyaluronic acid produced a decrease in comfort for the first 3 min ( P <0.05).

CONCLUSIONS

The instillation of hyaluronic acid eye drops increased the in vivo wettability of the hydrogel contact lens, and the duration of this effect was directly related to its concentration and viscosity.

Management Strategies for Evaporative Dry Eye Disease and Future Perspective

Dry eye disease (DED) is a common disorder that remains challenging from a clinical perspective. Unstable or deficient tear film is a major factor contributing to DED and the inability to resolve the loss of tear film homeostasis that accompanies DED can result in a vicious circle of inflammation and treatment-refractory disease. Recently recognized as a multifactorial disease, the main etiological subtypes of DED are aqueous-deficient and evaporative which exist on a continuum, although evaporative dry eye (EDE) is the more frequent classification. Although attaining greater recognition in recent years, there is currently no consensus and no clear recommendation on how to manage EDE. Clarity on the early diagnosis and treatment of EDE may facilitate the avoidance of progression to chronic inflammation, permanent damage to the ocular surface, and treatment-refractory disease. The purpose of this review was to identify current best practice for management of EDE in order to help clinicians in providing accurate diagnosis and optimized treatment. We summarize recent literature considering the role of the lipid layer on tear film stability, the importance of its composition and of its dynamic behavior, and the link between its malfunction and the insurgence and maintenance of tear film-related diseases. We have provided an assessment of the best management of lipid-deficient EDE based upon an understanding of disease pathophysiology, while indicating the flow of current treatments and possible future evolution of treatment approaches. Lipid containing eye drops may be considered as a step closer to natural tears from artificial aqueous tears because they more closely mimic the aqueous and lipid layers and may be used in combination with other management approaches. As a next step, we recommend working with a wider expert group to develop full guidelines to enable patient-centered management of EDE. Key pointsDry eye is a multifactorial disease of variable presentation with the tendency to become a chronic disease for which it is essential to identify and treat the main pathogenic mechanisms involved and tailor the treatment to the individual patient.Early intervention is needed to prevent the vicious cycle of DED and may require a multi-faceted management approach.EDE is not just a problem of MGD but can be the result of anything affecting blinking, mucin spreading, aqueous layer volume and content.Lipid-containing eye drops may provide significant relief of symptoms by improving the lipid layer and its spreading ability and, as such, are an appropriate component of the overall management of lipid-deficient EDE; natural lipid-containing eye drops should be the preferred treatment.

Stabilization of comfort and visual quality after the insertion of soft contact lenses

PURPOSE

To evaluate comfort, visual function, and in vivo wettability after the insertion of hydrogel and silicone hydrogel contact lenses for a better understanding of how long practitioners should wait for the initial evaluation of soft contact lenses.

METHODS

A short-term prospective, contralateral, randomized, and participant-masked study was carried out. Twenty healthy participants (25.4 ± 2.6 years) were evaluated after the insertion of two different soft contact lenses at different times (1, 5, 10, 20, 30 min). Ocufilcon D (hydrogel) and Somofilcon A (silicone hydrogel) contact lenses were randomly assigned to both eyes of the same participant. Comfort, visual function under photopic conditions in terms of high-contrast visual acuity, low-contrast visual acuity, contrast sensitivity, and in vivo wettability were measured.

RESULTS

There was an increase in comfort (p < 0.001), high-contrast visual acuity (p < 0.05), and contrast sensitivity (p < 0.001, only with silicone hydrogel) directly related to time after contact lens insertion. Besides, in vivo wettability suffered a statistically significant deterioration directly related to time with both contact lenses (p < 0.05). Except for comfort and contrast sensitivity, all the parameters stabilized their values 10 min after the insertion of both soft contact lenses. Additionally, in vivo wettability and visual acuity differences were found between hydrogel and silicone hydrogel contact lenses (p < 0.05).

CONCLUSIONS

It would be possible to properly evaluate high-contrast visual acuity, low-contrast visual acuity, and in vivo wettability 10 min after the insertion of both soft contact lenses.

Ethnic Differences of Corneal Parameters: A Cross-Sectional Study

Purpose:

To investigate the ethnic differences of corneal parameters in Arabs and other ethnicities.

Methods:

This study recruited 250 Saudi Arabian participants, 18–45 years of age. The McMonnies questionnaire was used to exclude participants with dry eye. The KR8800 auto refractometer (Topcon, Japan) was used to measure the refractive error. Oculus Keratograph 4 topography was used to assess 16 corneal parameters, including the k-readings, horizontal visible iris diameter, mean eccentricity index, asphericity, corneal shape factor, corneal flattening factor, sagittal height, sagittal curvature, and vertical palpebral aperture.

Results:

A statistically significant difference was found between male and female participants. Corneal parameters were compared to other ethnicities, including Caucasians and Asians, and those of Mongoloid origin. The horizontal visible iris diameter was wider in Saudi Arabians than in Asians but similar to Caucasians. The sagittal height was deeper and the corneal shape factor was higher than in the other ethnicities, and the eccentricity index was lower than that in Caucasians and Asians of Mongoloid origin.

Conclusion:

Our data provided normative corneal parameters of Saudi Arabians that may be useful for ophthalmic clinicians and designers of contact lenses. Furthermore, the parameters suggest that the corneal characteristics of Arabians are distinct from those of major ethnicities.

Cataract surgery and dry eye disease: A review

AIM

To review published literature concerning cataract surgery and dry eye disease (DED).

METHODS

A search was undertaken using the following: PubMed (all years), Web of Science (all years), Ovid MEDLINE(R) (1946 to 12 December 2019), Ovid MEDLINE(R) Daily Update 10 December 2019, MEDLINE and MEDLINE non-indexed items, Embase (1974-2019, week 49), Ovid MEDLINE (R) and Epub Ahead of Print, In-Process and Other Non-Indexed Citations and Daily (1946 to 12 December 2019), CENTRAL (including Cochrane Eyes and Vision Trials Register; Cochrane Library: Issue 12 of 12 December 2019), metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and WHO International Clinical Trials Registry Platform (www.who.int/ictrp/search/en). Search terms included 'cataract surgery', 'phacoemulsification' and 'cataract extraction', combined with 'dry eyes' and 'ocular surface'. Relevant in-article references not returned in our searches were also considered.

RESULTS

Publications identified included systematic reviews, meta-analysis, randomized controlled trials, cohort studies, case series and laboratory-based studies. Published data highlighting the burden of DED both prior and following cataract surgery were reviewed as well as studies highlighting the effects of cataract surgery on the ocular surface, intra-operative measures to reduce deleterious effects on the ocular surface and current evidence on the management options of post-operative DED.

CONCLUSIONS

DED is common and can be exacerbated by cataract surgery. Ophthalmologists need to assess for pre-existing DED and instigate treatment before surgery; be aware of reduced accuracy of measurements for surgical planning in the presence of DED; limit intra-operative surgical factors damaging to the ocular surface; and consider management to reduce DED post-operatively.

Patient-Reported Burden of Dry Eye Disease in the United States: Results of an Online Cross-Sectional Survey

PURPOSE

To evaluate functional vision, general health status, and work productivity in individuals with and without dry eye disease (DED).

DESIGN

Cross-sectional study.

METHODS

Setting: General US population (2018).

STUDY POPULATION

Adults ≥18 years with (n = 1003) or without (n = 1006) self-reported DED.

MAIN OUTCOME MEASURES

All respondents completed the National Eye Institute Visual Function Questionnaire (VFQ) and the EuroQol 5-dimensions 5-levels (EQ-5D-5L). All respondents with DED completed the eye dryness score (EDS) visual analogue scale, Ocular Comfort Index (OCI), and Work Productivity and Activity Impairment (WPAI) questionnaire. Half of respondents with DED completed the Impact of Dry Eye on Everyday Life (IDEEL) questionnaire; the other half completed the Dry Eye Questionnaire 5 (DEQ-5) and Standardized Patient Evaluation of Eye Dryness (SPEED), McMonnies, and Symptom Assessment in Dry Eye (SANDE) questionnaires. All analyses were descriptive.

RESULTS

Respondents with DED reported more comorbidities, greater exposure to adverse environmental conditions, and lower (worse) mean (standard deviation) scores on the modified Rasch-scored 28-item VFQ (VFQ-28R) total score (68.8 [11.9] vs 81.2 [12.7]) and EQ-5D-5L (0.82 [0.13] vs 0.88 [0.14]) than respondents without DED. Respondents with DED and EDS ≥60 (highest discomfort) fared worse on OCI, VFQ-28R, and WPAI than respondents with DED and EDS <40 (lowest discomfort). Similar findings were observed with IDEEL, DEQ-5, SPEED, McMonnies, and SANDE scores.

CONCLUSIONS

There is a substantial burden of DED on functional vision, general health status, and productivity; and further, these parameters appear to worsen with increasing EDS.

Trends in the Utilization of Sodium Hyaluronate Eye Drops, Including Disposable and Multiuse Forms, in South Korea: A 14-Year Longitudinal Retrospective Cohort Study

Introduction

Sodium hyaluronate eye drops are frequently prescribed for dry eye disease in South Korea.

Objectives

This study analyzed the trends in the utilization of sodium hyaluronate eye drops and evaluate the impact of the introduction of high-priced disposable forms in the South Korean market.

Methods

The yearly claims data for sodium hyaluronate eye drops from 2002 to 2015 were retrieved from the National Health Insurance Service-National Sample Cohort. Prescriptions of sodium hyaluronate eye drops were sorted by the characteristics of patients and health care institutions.

Results

The number of prescriptions has continuously increased and the share of disposable forms in total prescriptions reached 37% in 2015. Particularly, the prevalence of prescriptions (general users) has increased during the study period from 2,562/100,000 persons in 2002 to 14,732/100,000 persons in 2015, while the incidence of prescriptions (new users) has remained steady during the study period, approximately 3,500/100,000 persons. More female patients were noted in terms of general users and new users, and the proportion of male patients was higher in new users than in general users. The average age of general users increased during the study period, while that of new users slightly decreased. Finally, the distribution of prescription category was significantly different between sex and age groups in frequently prescribed users.

Conclusions

Eye drops in disposable forms, which are safe and more convenient to use, have expanded the market in South Korea and caused equity issues in utilization. Thus, the utilization of eye drops should be closely monitored from the perspectives health equity.

Tear Film Dynamics of Soft Contact Lens-Induced Dry Eye

PURPOSE

This study aimed to prospectively assess tear dynamics in soft contact lens-induced dry eye while wearing and after removing the soft contact lenses.

MATERIALS AND METHODS

We analyzed 17 right eyes of soft contact lens users at Wada Eye Clinic (11 men, 6 women; mean age: 36.8 ± 8.3 years; range: 24-57 years). Participants were divided into two groups depending on presence of dry eye symptoms. Video interferometry was used to observe tear dynamics while wearing and after removing soft contact lenses. Interference images focusing on tear spread and interference fringe were compared between groups.

RESULTS

This study included 10 symptomatic and 7 asymptomatic eyes. Considering the symptomatic eyes, while wearing soft contact lenses, 8 eyes showed poor tear spread and multicolor interference fringe, i.e., swift flow of multicolor interference waves after a grayish monochromatic band-color after a blink, but 8 and 10 eyes showed good tear spread and a grayish monochromatic interference fringe when soft contact lenses were removed, respectively. As for asymptomatic eyes, 6 eyes exhibited good tear spread and a grayish monochromatic interference fringe while wearing soft contact lenses and after removing soft contact lenses.

CONCLUSIONS

soft contact lens-induced dry eye was associated with tear dynamics only while wearing soft contact lenses. Observation of tear film dynamics in eyes with soft contact lenses could facilitate the understanding of dry eye-related symptoms.

Dry Eye Disease: A Review of Epidemiology in Taiwan, and its Clinical Treatment and Merits

Dry eye disease (DED) has become common on a global scale in recent years. There is a wide prevalence of DED in different countries based on various ethnicities and environment. DED is a multifactorial ocular disorder. In addition to advanced age and gender, such factors as living at high altitude, smoking, pterygium, prolonged use of consumer electronics or overingesting of caffeine or multivitamins are considered to be the major risk factors of DED. We report the DED epidemiology in Taiwan firstly in this article. According to the pathophysiological factors and changes inthe composition of the tear film in DED, it can be categorized into several subtypes, including lipid anomaly dry eye, aqueous tear deficiency, allergic and toxic dry eye among others. Each subtype has its own cause and disease management; therefore, it is important for ophthalmologists to identify the type through literature review and investigation. The management of DED, relies not only on traditional medications such as artificial tears, gels and ointments, but also newer treatment options such as acupuncture, SYL1001, and nanomedicine therapy. We also conducted a comprehensive literature review including common subtypes and treatment of DED. Clearly, more clinical trials are needed to assess the efficacy and safety of the various treatments and common subtypes of DED.

Functional Visual Acuity

Dry eye (DE) causes irregularity of the ocular surface and reduces the quality of vision. An intact, regular tear film is essential for high-quality retinal images; however, visual tasks requiring sustained gazing can disrupt the tear film, eventually degrading visual function. A functional visual acuity (FVA) measurement system has been uniquely developed in Japan to evaluate visual function related to tear stability in patients with DE. FVA has been shown to correlate with optical quality. The system measures the change in visual acuity (VA) over time automatically in aqueous-deficient DE and short tear breakup tear film DE characterized by decreased tear stability and minimal epithelial damage. It is also useful to detect minimal visual deterioration correlated with minimal ocular surface abnormality and vision-related quality of life otherwise undetectable by conventional VA testing, to assess and quantify vision-related symptomatology, and to determine the efficacy of treatments for DE disease. Recently, its use has been expanded, such as for the analysis of visual function accompanying refractive surgery, contact lens, cataract and cataract-related disease, retinal disease, glaucoma, amblyopia, presbyopia, and vehicle driving. Its use has revealed that FVA reflects not only visual function related to tear dynamics, but also visual function related to quick recognition of the target. This simple, noninvasive, and sensitive FVA measurement system may be expected to be used worldwide.

Evaluation of Reliability and Validity of Three Common Dry Eye Questionnaires in Chinese

Purpose

To investigate the psychometric properties of three commonly used dry eye questionnaires including McMonnies Questionnaire (MQ), the Ocular Surface Disease Index (OSDI), and the Salisbury Eye Evaluation Questionnaire (SEEQ) in Chinese.

Methods

This prospective cross-sectional study was conducted at the Eye Hospital of Wenzhou Medical University. Ninety-eight participants completed three questionnaires in a random order. Ophthalmic examinations including tear break-up time, corneal fluorescein staining score, and Schirmer I test were performed. Reliability, validity, and accuracy were assessed for three questionnaires.

Results

There were 35 mild-to-moderate dry eye patients, 14 severe dry eye patients, and 49 non-dry eye patients. The Cronbach α of MQ, OSDI, and SEEQ was 0.54, 0.74, and 0.76, respectively, and the intraclass correlation coefficients were 0.91, 0.90, and 0.94, respectively. There were significant differences (P < 0.05) in MQ and OSDI scores among different groups, but there were no statistically significant differences between the mild-to-moderate group and the severe group in terms of SEEQ scores. With cutoff values for abnormal MQ of 15, OSDI of 27.2, and SEED of 1, respectively, good dry eye diagnostic accuracies were obtained.

Conclusions

The three questionnaires showed fair accuracy in the diagnosis of dry eye. The cutoff values of OSDI changed when applied to Chinese people.

Dry eye disease in patients with metabolic syndrome

OBJECTIVES

To evaluate dry eye disease (DED) in patients with metabolic syndrome (MetS) and compare with healthy individuals.

METHODS

The study was conducted in the Ophthalmology and Endocrinology Department of Bagcilar Education and Research Hospital, a tertiary care center in Istanbul, Turkey, between January and December 2015. In this prospective case-controlled study, dry eye disease tests were performed on 44 patients with MetS and 43 healthy controls. TearLab Osmolarity System, which is a lab-on-a-chip technology, was used to measure tear osmolarity. McMonnies & Ho symptoms questionnaire along with Schirmer I test and tear film break-up time (TFBUT) test were also performed. Statistical evaluation was performed by students' independent test.

RESULTS

There was no statistically significant difference in tear osmolarity, TFBUT, and McMonnies and Ho questionnaire scores between MetS and normal group. However, Schirmer I test was significantly higher in MetS group (14.8±9.4mm versus 20.4±9.4, p=0.007). In women subgroup, tear osmolarity was significantly higher in MetS group compared  to the normal group and over the cut-off score 308 mOsm/L (309.4±13.1 mOsm/L versus 301.2±8.7mOsm/L, p=0.012).

CONCLUSION

Patients with MetS present with lower tear volumes and a higher incidence of lacrimal gland hypofunction than age-matched controls. Especially women with MetS have higher tear osmolarities, which disrupt the normal functioning of the ocular surface and cause inflammation. Clinicians should be aware of higher DED incidence in patients with MetS for early treatment to prevent serious ocular complications.

Clinical relationship of meibometry with ocular symptoms and tear film stability

PURPOSE

To evaluate the relationship between meibometry with both ocular symptoms and tear film stability by: (1) to find out whether meibometry is able to differentiate between dry eye symptomatic and asymptomatic subjects classified by standardized dry eye questionnaires (OSDI and McMonnies), and (2) to assess the clinical relationship between meibometry with both tear break-up time (BUT) and maximum blink interval (MBI).

METHODS

140 Patients were recruited for the study. Using Meibometer MB550, five curves were generated for each patient. Subjects performed OSDI and McMonnies questionnaires and were stratified following a two- and a three-subgroup stratification for each questionnaire. BUT/MBI were repeated three times (by video recordings), and they were determined by counting their frames.

RESULTS

Subjects grouped by OSDI showed a trend to present lower meibometry values as the OSDI score were higher (ANOVA, p≤0.044). For McMonnies questionnaire this was only true for the two-subgroup stratification (ANOVA, p=0.04), but not for three-subgroup stratification (one-way ANOVA, p=0.30). On the other hand, meibometry values showed a statistical correlation with both BUT (r=0.305, p<0.001) and MBI (r=0.265, p<0.001). When the sample was divided in three groups regarding BUT value (≤5s, between 5 and 10s and≥10s), significant differences of meibometry values were found between BUT subgroups (p=0.008).

CONCLUSION

Meibometer MB550 can discriminate asymptomatic from dry eye symptomatic patients. Furthermore, there is a relationship between meibometry and the tear film stability.

Hyperosmotic stress induces ATP release and changes in P2X7 receptor levels in human corneal and conjunctival epithelial cells

Tear hyperosmolarity is a key event in dry eye. In this work, we analyzed whether hyperosmolar challenge induces ATP release on the ocular surface. Moreover, as extracellular ATP can activate P2X7 receptor, the changes in P2X7 protein levels and its involvement in pathological process triggered by hypertonic treatment were also examined. High-performance liquid chromatography analysis revealed that ATP levels significantly increased in human corneal and conjunctival epithelial cells exposed to hyperosmotic challenge as well as in dry eye patients as compared to control subjects. A significant reduction in cell viability was detected after hyperosmolar treatment, indicating that the rise in ATP release was mainly due to cell lysis/death. Additionally, vesicular nucleotide transporter was identified in both cell lines and their protein expression was upregulated in hypertonic media. P2X7 receptor truncated form together with the full-length form was identified in both cell lines, and experiments using specific antagonist and agonist for P2X7 indicated that this receptor did not mediate cell death induced by hyperosmolar stress. In conclusion, hyperosmotic stress induces ATP release. Extracellular ATP can activate P2X7 receptor leading to cytotoxicity in many cells/tissues; however, this does not occur in human corneal and conjunctival epithelial cells. In these cells, the presence of P2X7 receptor truncated form together with the full-length form hinders a P2X7 apoptotic behavior on the ocular surface.

Rasch analysis of three dry eye questionnaires and correlates with objective clinical tests

PURPOSE

To assess the psychometric properties of Chinese versions of the Ocular Comfort Index (OCI), Ocular Surface Disease Index (OSDI) and McMonnies questionnaires. Further, to assess the correlation between questionnaire scores and objective dry eye disease (DED) clinical tests.

METHODS

Translated versions of the OCI, OSDI and McMonnies questionnaires were completed in a random order by 238 participants with DED. Objective clinical tests included visual acuity (VA), fluorescein tear film break-up time (TBUT), corneal fluorescein staining, Schirmer I testing and meibomian gland grading. Rasch analysis was used to assess questionnaire psychometrics and spearman rank for correlations.

RESULTS

For the OCI, the person separation was 2.31, item infit and outfit statistics ranged from 0.74-1.14 and 0.75-1.32, respectively, and targeting 1.54 logits. For the OSDI, person separation was 0.94. None of the three subscales provided valid measurements based on Rasch analysis. For the McMonnies questionnaire, person separation was 1.17, item infit and outfit statistics ranged from 0.7 to 1.21 and 0.51-3.49, respectively. There were weak correlations between questionnaire scores and clinical tests. There were weak correlations between OSDI scores and VA, fluorescein TBUT, Schirmer I testing and corneal fluorescein staining. There were weak correlations between McMonnies scores and VA, fluorescein TBUT, Schirmer I testing, and corneal fluorescein staining and meibomian gland grading.

CONCLUSIONS

The OCI questionnaire was the only questionnaire that provided valid measurement on the basis of Rasch analysis, although slight multidimensionality was found. There were weak correlations between OCI scores and fluorescein TBUT, Schirmer I testing, and corneal fluorescein staining. Due to this paradoxical disconnect between symptoms and signs and the repeatability of tests, the use of both subjective and objective markers in the clinical management of patients or as endpoints in clinical trials would appear prudent.

The Relationship Between Tear Ferning Patterns and Non-invasive Tear Break-up Time in Normal Asian Population

PURPOSE

To investigate the relationship between tear ferning patterns (TFP) and non-invasive tear break-up time (NIBUT) in normal Asian subjects.

METHODS

One hundred and forty-five adults with no ocular surface disorders were recruited. TFP and NIBUT were determined. Tears were collected using a capillary tube and allowed to air dry at room temperature for 10min. TFP was later observed using a light microscope and classified according to Rolando's classification. Measurement for NIBUT was obtained using a Tearscope with the slit lamp magnification.

RESULTS

It was found that there is no significant difference between gender in TFP (Z=-1.77, P>.05) and NIBUT (Z=-1.475, P>.05). There is also no significant difference between Malay, Chinese, Indian, and other races in TFP, (H(3)=4.85, P>.05) and NIBUT (H(3)=2.18, P>.05). However, there is a significant difference between age groups of 20-29, 30-39, 40-49,and 50-60 years old in both TFP (H(3)=28.25, P<.01) and NIBUT (H(3)=36.50, P<.001). Spearman's correlation showed there was a significant relationship between TFP and NIBUT (r=-0.55, P<.001), age and NIBUT (r=-0.50, P<.001), age and TFP (r=0.41, P<.001), McMonnies score and NIBUT (r=-0.40, P<.001), McMonnies score and TFP (r=0.31, P<.001), as well as age and McMonnies score (r=0.52, P<.001).

CONCLUSION

TFP and NIBUT was age dependent but not gender and race dependent. Older subjects had higher grade of TFP and McMonnies questionnaire score but lower NIBUT value. TFP and NIBUT can be used to assess the tear film quality.

Diagnostic Performance of McMonnies Questionnaire as a Screening Survey for Dry Eye: A Multicenter Analysis

Purpose. To evaluate the diagnostic performance of the McMonnies questionnaire as a screening survey for dry eye in Chinese outpatients. Methods. The questionnaire was self-administered by 27,999 patients with dry eye symptoms. A thorough ophthalmic examination including tear break-up time (TBUT), fluorescein staining, and Schirmer I test was completed to make a clinical diagnosis of dry eye. Reliability, validity, and accuracy of the McMonnies questionnaire were assessed. Results. The McMonnies questionnaire showed poor internal consistency (Cronbach α = 0.37), but excellent validity as the scores correlated with TBUT (Spearman test, r = −0.322, P < 0.001) and Schirmer I test (Spearman's test, r = −0.370, P < 0.001), and significantly differed between the dry eye and control groups (2-sample t-test, t = 69.51, P < 0.001). The area under the receiver-operating characteristics (ROC) curve (AUC) was 0.729, suggesting moderate accuracy in identifying dry eye and non-dry eye patients. However, the AUCs varied significantly in different gender and age subgroups (z test, P < 0.001), as the discriminating ability declined with age. Analysis of the ROC curves also revealed that different cut-off points should be employed for each subgroup to achieve the same level of accuracy. Conclusions. The McMonnies questionnaire demonstrates moderate diagnostic value, and different cut-off points should be selected for various study populations.

Accuracy of McMonnies Questionnaire as a Screening Tool for Chinese Ophthalmic Outpatients

Objective

To evaluate the accuracy of the McMonnies questionnaire (MQ) as a screening tool for dry eye (DE) among Chinese ophthalmic outpatients.

Methods

We recruited 27718 cases from 94 hospitals (research centers), randomly selected from 45 cities in 23 provinces from July to November in 2013. Only symptomatic outpatients were included and they were in a high risk of DE. Outpatients meeting the criteria filled out questionnaires and then underwent clinical examinations by qualified medical practitioners. We mainly evaluated sensitivity, specificity, diagnostic odds ratio (DOR), and area under the receiver-operating characteristic curve (AUC) to evaluate the accuracy of the questionnaire in the diagnosis of dry eye.

Results

Of all the subjects included in the study, sensitivity, specificity, and DOR were 0.77, 0.86 and 20.6, respectively. AUC was 0.865 with a 95% CI (0.861, 0.869). The prevalence of DE among the outpatients claiming “constantly” as the frequency of symptom was over 90%. Scratchiness was a more accurate diagnostic indication than dryness, soreness, grittiness or burning. Different cut points of McMonnies Index (MI) scores can be utilized to optimize the screening results.

Conclusions

MQ can be an effective screening tool for dry eye. We can take full advantage of MI score during the screening process.

The Effects of Hemodialysis on Tear Osmolarity

Aim. To determine the effects of hemodialysis (HD) on tear osmolarity and to define the blood biochemical tests correlating with tear osmolarity among patients with end stage renal disease (ESRD). Material-Method. Tear osmolarity of ESRD patients before and after the hemodialysis program was determined as well as the blood biochemical data including glucose, sodium, potassium, calcium, urea, and creatinine levels. Results. Totally 43 eyes of 43 patients (20 females and 23 males) with a mean age of 53.98 ± 18.06 years were included in the study. Tear osmolarity of patients was statistically significantly decreased after hemodialysis (314.06 ± 17.77 versus 301.88 ± 15.22 mOsm/L, p = 0.0001). In correlation analysis, pre-HD tear osmolarity was negatively correlated with pre-HD blood creatinine level (r = −0.366,  p = 0.016). Post-HD tear osmolarity was statistically significantly correlated with the post-HD glucose levels (r = 0.305  p = 0.047). Tear osmolarity alteration by HD was negatively correlated with creatinine alteration, body weight alteration, and ultrafiltration (r = −0.426,  p = 0.004; r = −0.365,  p = 0.016; and r = −0.320, p = 0.036, resp.). There was no correlation between tear osmolarity and Kt/V and URR values. Conclusion. HD effectively decreases tear osmolarity to normal values and corrects the volume and composition of the ocular fluid transiently. Tear osmolarity alteration induced by HD is correlated with body weight changes, creatinine alterations, and ultrafiltration.

Diadenosine polyphosphates in the tears of aniridia patients

PURPOSE

To quantify diadenosine polyphosphate levels in tears of congenital aniridia patients to estimate the ocular surface changes associated with congenital aniridia compared to normal individuals.

METHODS

Fifteen patients diagnosed with congenital aniridia and a control group of forty volunteers were studied. Tears were collected to quantify the levels of diadenosine polyphosphates Ap4 A and Ap5 A by high-performance liquid chromatography (H.P.L.C). Break-up time (BUT), corneal staining, McMonnies questionnaire and the Schirmer I test were applied to both groups.

RESULTS

Dinucleotides in congenital aniridia patients were higher than in control subjects. For the congenital aniridia group, under 15 years old, the values were 0.77 ± 0.01 μm and 0.17 ± 0.02 μm for Ap4 A and Ap5 A, respectively. The group aged from 15 to 40 years old provided concentrations of 4.37 ± 0.97 μm and 0.46 ± 0.05 μm for Ap4 A and Ap5 A, the group over 40 gave concentrations of 11.17 ± 5.53 μm and 0.68 ± 0.17 μm for Ap4 A and Ap5 A. Dinucleotide concentrations increased with age, being statistically significant different among the three age groups (p < 0.05). Congenital aniridia patients showed a normal tear secretion and no dry eye McMonnies scores, except for the group over 40 years old. BUT values decreased and corneal staining increased with age and correlated with the levels of diadenosine polyphosphates (p < 0.05).

CONCLUSIONS

The levels of dinucleotides in tears increase in aniridia patients compared with healthy subjects, and they seem to be related with the progression of corneal disorders in aniridia patients, both of which increase with ageing.

Diagnosing the severity of dry eye: a clear and practical algorithm

Dry eye disease (DED) is a distressing ocular condition. Due to its multifactorial nature, clinical and biological signs of DED can be inconsistent and sometimes discordant with symptomatology. Consequently, no gold-standard model for determining DED severity exists. This can impact treatment decisions and complicate evaluation of disease progression, particularly within the stringent context of clinical trials. The multinational ODISSEY European Consensus Group is comprised of ophthalmologists who contend with ocular surface disease issues on a daily basis. This group convened to establish a clear and practical algorithm for evaluation and diagnosis of severe DED. Using a consensus-based approach, they assessed 14 commonly used DED severity criteria. The panel agreed that following confirmed DED diagnosis, just two criteria, symptom-based assessment and corneal fluorescein staining were sufficient to diagnose the presence of severe DED in the majority of patients. In the event of discordance between signs and symptoms, further evaluation using additional determinant criteria was recommended. This report presents the ODISSEY European Consensus Group recommended algorithm for DED evaluation, which facilitates diagnosis of severe disease even in the event of discordance between signs and symptoms. It is intended that this algorithm will be useful in a clinical and developmental setting.

A Clinical Study of Subtype-based Prevalence of Dry Eye

INTRODUCTION

Dry Eye is a multifactorial disease of the tearfilm and the ocular surface which may be due to reduced tear production or excessive tear evaporation resulting in discomfort, visual disturbance, and tear film instability with a potential damage to the ocular surface. Various population-based studies have been done to find out the prevalence and the magnitude of the problem. Women Health Study reported prevalence of 7.8% after screening 36995 subjects above 49 years by interview. The prevalence reported by Blue Mountain Study was 15.3% .The Beaver Dam Study and Shiphai Eye studies are other studies reporting prevalence of 14.5% and 33.7% respectively. McMonnies questionnaire is a widely used screening instrument for Dry-Eye syndromes with sensitivity reportedly varying between 87% and 98% and specificity between 87% and 97%. Prevalence studies use McMonnie's questionnaire for screening individuals for Dry Eye, whereafter tests like Schirmer's test, Tear Film Break Up Time test, Rose Bengal test, Lissamine Green test and Meibomian Gland Dysfunction test are useful for further evaluation. While these tests help to differentiate the subtypes of Dry Eye such as Lipid Anomaly Dry Eye, Aqueous Tear Deficiency and Mucin Layer Deficiency, however, their sensitivity and specificity has not been widely studied. Additionally, very few studies have reported the prevalence of the various subtypes of Dry Eye.

AIM AND OBJECTIVES

To determine the subtype-based prevalence of Dry Eye, to study the specificity and sensitivity of clinical tests for Dry Eye and to correlate McMonnies questionnaire with Dry Eye tests results.

MATERIAL AND METHODS

A prospective, cross-sectional, observational study, duly approved by the Institutional Ethics Committee, was conducted from October 2010 to April 2012. A total of 4750 subjects above 18 yrs of age were screened by the McMonnies questionnaire. Respondents having a score greater than 14.5 were subjected to clinical Dry Eye tests. The data obtained was analyzed using chi-square test. p value < 0.005 was considered statistically significant.The specificity and sensitivity of each clinical test was calculated using Schirmer's test as gold standard.

RESULTS

The prevalence of Dry Eye was 15.4%, with a female preponderance (p = 0.01) and a significant increase with age above 60 years was noted (p<0.0001). Tear Film Break Up Time was the most reliable test with a good sensitivity (68.85%) and specificity (78.32%). Lipid Anomaly Dry Eye was the most prevalent (14.48%) followed by Aqueous Tear Deficiency (13.36%) and Mucin Layer Deficiency (3.51%). A positive correlation between McMonnies score and severity of Dry Eye was seen.

CONCLUSION

This study suggests that Lipid Layer Anomaly is the most prevalent subtype in Dry Eye. Tear Film Break Up Time test is the most likely test to diagnose mild Dry Eye. McMonies Questionnaire can be effectively used for screening of a large population. Tear Film Break Up Time was found to have better sensitivity as well as specificity than other tests used for diagnosing Dry Eye.

Diadenosine polyphosphates release by human corneal epithelium

Diadenosine polyphosphates are a type of dinucleotides that have been detected in rabbit and human tears. However, their origin and their mechanism of release have not been fully elucidated. In this work we investigated whether the dinucleotides Ap4A and Ap5A can be released from human corneal epithelia as a consequence of shear stress stimuli. In in vitro experiments, concentrations of Ap4A and Ap5A before mechanical stimulus of stratified human corneal epithelial cells were 3.18 ± 0.43 nM and 0.81 ± 0.13 nM, respectively. After shear stimulation, concentrations significantly increased to 12.01 ± 2.19 nM for Ap4A and 2.83 ± 0.41 nM for Ap5A. No significant differences in lactate dehydrogenase activity were detected between non-stimulated stratified human corneal epithelial cells and cells exposed to mechanical shear-stress, indicating that the rise of dinucleotide levels was not due to cell lysis. In in vivo experiments, individuals subjected to a rise in blinking frequency showed a significant increase of Ap4A (∼25-fold when experiment was performed without anaesthetic and 75-fold with anaesthetic) and Ap5A concentration in tears (∼50-fold when experiment was performed without anaesthetic and 125-fold with anaesthetic). Shear-stress stimuli induces Ap4A and Ap5A release from human corneal epithelium, thus explaining the origin of these relevant compounds for the ocular surface biochemistry and physiology.

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.

Influence of the blink interval on tear meniscus height in soft contact lens and nonlens wearers

PURPOSE

Tear meniscus height (TMH) is an indirect measurement of tear film volume. This study investigated the temporal changes in the TMH during the blink interval in the morning (8-9 am) and at the end of the day (5-6 pm) in both soft contact lens (CL) and nonlens wearers (NLW).

METHODS

Fifty participants (25 CL; 25 NLW) were evaluated for their subjective symptoms, TMH, noninvasive break up time, and bulbar hyperemia at the am and pm visits on the same day. The TMH was measured at set intervals between 2 and 15 sec during the blink interval, using an optical coherence tomographer.

RESULTS

The NLW group revealed no changes in a variety of symptoms during the day, whereas the CL group reported an increase in dryness (P=0.03) and grittiness (P=0.02) over the day. For both groups, the TMH and calculated tear meniscus volume revealed lower values immediately after the blink and increased progressively afterwards, mainly due to reflex tearing. The am tear meniscus volume values tended to be higher than the pm values for both groups, but this was not significant (NLW P=0.13; CL P=0.82). Noninvasive break up time deteriorated during the day for both groups but was only significant for the CL group (P=0.002), whereas bulbar hyperemia revealed no statistically significant change for either group.

CONCLUSIONS

Reflex tearing may play a substantial role in the TMH differences observed over the blink interval. Standardization of the time when a TMH measurement is performed will be valuable in comparing tear film clinical studies.

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

PURPOSE

With the potential to address evaporative dry eye, a novel spray has been developed in which phospholipid liposomes are delivered to the tear film via the surface of the closed eyelid. This study evaluated the short-term effects of liposomal spray application on the lipid and stability characteristics of the pre-ocular tear film in normal eyes.

METHODS

Twenty-two subjects (12M, 10F) aged 35.1+/-7.1 years participated in this prospective, randomised, double-masked investigation in which the liposomal spray was applied to one eye, and an equal volume of saline spray (control) applied to the contralateral eye. Lipid layer grade (LLG), non-invasive tear film stability (NIBUT) and tear meniscus height (TMH) were evaluated at baseline, and at 30, 60, 90 and 135min post-application. Subjective reports of comfort were also compared.

RESULTS

Treated and control eyes were not significantly different at baseline (p>0.05). Post-application, LLG increased significantly, at 30 and 60min, only in the treated eyes (p=0.005). NIBUT also increased significantly in the treated eyes only (p<0.001), at 30, 60 and 90min. TMH did not alter significantly (p>0.05). Comfort improved relative to baseline in 46% of treated and 18% of control eyes, at 30min post-application. Of those expressing a preference in comfort between the eyes, 68% preferred the liposomal spray.

CONCLUSIONS

Consistent with subjective reports of improved comfort, statistically and clinically significant improvements in lipid layer thickness and tear film stability are observed in normal eyes for > or =1h after a single application of a phospholipid liposomal spray.

Dinucleoside polyphosphates in the eye: from physiology to therapeutics

Diadenosine polyphosphates are a family of dinucleotides with emerging biochemical, physiological, pharmacological and therapeutic properties in the eye and other tissues. These compounds are formed by two adenosine moieties linked by their ribose 5'-ends to a variable number of phosphates. Diadenosine polyphosphates are present as active components of ocular secretions such as tears and aqueous humour and they can activate P2 purinergic receptors present on the ocular surface, anterior segment and retina. Both metabotropic and ionotropic actions mediated by P2Y and P2X receptors, respectively are responsible for the control of processes such as induction of tear secretion, lysozyme production or acceleration of corneal wound healing. Inside the eye the dinucleotide Ap(4)A can reduce intraocular pressure by acting on P2Y(1) receptors present in trabecular meshwork cells and on P2X(2) receptors present on the cholinergic terminals located in the ciliary muscle. In the retina, derivatives of diadenosine polyphosphates can improve the re-absorption of fluids in retinal detachment. Altogether, diadenosine polyphosphates are not only dinucleotides with roles in the physiology of the eye but it is also possible that their properties may serve to help in the treatment of some ocular pathologies.

Rheumatoid arthritis is a risk factor for dry eye in the Indian population

PURPOSE

To compare the prevalence and severity of dry eye in patients with rheumatoid arthritis (RA) with that in age- and sex-matched controls in the Indian population.

METHODS

A cross-sectional study was performed on 84 randomly selected eyes of 84 adult patients with well-documented rheumatoid arthritis and 84 eyes of 84 age- and sex-matched controls in the Department of Ophthalmology, Seth G.S. Medical College and K.E.M. Hospital. McMonnie's dry eye questionnaire was used to classify the patients on the basis of their symptoms. Dry eye was diagnosed if the wetting on Schirmer filter paper test was < or =5 mm at 5 minutes and the tear film breakup time was < 10 seconds on slit-lamp examination after fluorescein staining.

RESULTS

Twenty three patients (27.3%) with rheumatoid arthritis had dry eyes based on the Schirmer test as compared to 10 (12%) age- and sex-matched controls; 19 (22.62%) patients with RA had a tear film breakup time of < 10 sec. on slit-lamp examination, compared to 8 (9.52%) patients without RA. The difference in the mean wetting (p = 0.003) and mean tear film breakup time (p < 0.001) between RA and non-RA patients was statistically significant. Ocular symptoms had a limited correlation with the results of these tests.

CONCLUSIONS

Patients with RA in the Indian population have a significantly higher prevalence and severity of dry eye when compared to age- and sex-matched controls.

Patient-reported symptoms in dry dye disease

Clinically, dry eye has often been reported as a "symptom-based" disease, and definitions of dry eye based on symptoms have been used to define dry eye prevalence in population-based studies. Given this, patient-reported symptoms often do not correlate with diagnostic tests unless disease is severe or testing is tightly controlled. Progress in the understanding of dry eye symptoms has been made over the last 10 years; however, the link between symptoms and disease status, such as ocular surface damage or inflammation, remains elusive. Although several surveys for dry eye have been developed for screening or diagnosis, an accepted, validated survey capable of accurately monitoring changes with time or treatment is not available. Common symptoms, available surveys, and the associations between diagnostic tests and symptoms are reviewed.

Temporal changes in the tear menisci following a blink

This study investigated tear meniscus formation after a blink. Multiple images of the inferior and superior menisci, viewed en-face, were sequentially captured using a video-slitlamp that permitted the measurement of tear meniscus height (TMH). In a similar manner, tangentially viewed images were obtained of the inferior meniscus so changes in cross-sectional radius of curvature (TMR) with time could be determined. Additionally, the relationship between inferior TMH and tear volume was quantified by the successive instillation of small aliquots of fluid. In this latter experiment the inflow and outflow of tears were controlled by anaesthetizing the ocular surface and inner nose, and use of punctal plugs. The TMH of both menisci rose after a blink (p<0.01) by a similar amount (p=0.59). This suggests that capillarity is dominant over gravity in tear drainage, however, it may simply reflect that these influences are small compared to the large flow resistances that occur in thin films, hydraulic connectivity between the two menisci, or differences in their anterior-posterior width leading to unequal volume-height relationships. TMR increased with time after a blink (p<0.0001); immediately on eye opening the curvature of the inferior meniscus was approximately circular but this soon became eccentric, with the radius of its upper half exceeding that of its lower half. The growth rate of the two menisci slowed with time and this, based on theoretical considerations, is predicted to have occurred primarily because localized thinning of the tear film adjacent to the menisci markedly raised flow resistance. Inferior TMH increased linearly with the cumulative volume of instilled fluid (r2=0.98), supporting its use in the diagnosis and classification of tear anomalies, although the gradient of this relationship varied between subjects.

The Agreement and Repeatability of Tear Meniscus Height Measurement Methods

PURPOSE

This study investigated the agreement and repeatability of five techniques of measuring tear meniscus height (TMH).

METHODS

Pairs of TMH measurements were obtained from one eye of 25 normal subjects with five techniques: optical coherence tomography in cross-section (OCT) and optical pachymetry in cross-section (PACH), without fluorescein; and 5 minutes after the instillation of fluorescein, optical pachymetry en-face (SL-F) and in cross-section (SL-X), and video capture en-face (VC). These 10 measurements were taken on different days within a period of 21 days. Additionally, immediately successive replicates were taken at the first visit when VC was used, allowing for the separation of technique repeatability from true day-to-day variation in TMH.

RESULTS

Ninety-five percent confidence intervals for the mean TMH and 95% repeatability coefficients for repeated testing on separate occasions were: 0.25 to 0.29 mm, 0.14 mm--OCT, 0.30 to 0.36 mm, 0.13 mm--PACH, 0.27 to 0.34 mm, 0.092 mm--SL-F, 0.35 to 0.41 mm, 0.19 mm--SL-X, and 0.30 to 0.38 mm, 0.088 mm--VC. Reported repeatability coefficients are averages because, despite a relatively narrow experimental range, the measurements of low TMH were generally more repeatable than those of large TMH. Ninety-five percent limits of agreement were wide for all pairwise comparisons and included zero, indicating that the methods used in this study are interchangeable when taking single recordings, at least on subjects without dry eye.

CONCLUSIONS

The average TMH of the five techniques was similar, although OCT and SL-X tended to record lower and higher values, respectively. However, their agreement for single recordings was poor, an inevitable consequence of the low intertest repeatability found for all methods. A much improved repeatability for immediate replicates indicated that this, in turn, was principally caused by a large day-to-day variation in TMH rather than measurement error.

The Diagnosis and Characteristics of Moderate Dry Eye in Non-Contact Lens Wearers

PURPOSE

To identify and characterize moderate dry eye in non-contact lens wearers with a new scoring system-based dry eye questionnaire and to determine which objective tests better differentiate patients with moderate dry eye from healthy patients.

METHODS

Fifty-two healthy subjects (21 women and 31 men with a mean age of 27.8 +/- 9.2 years) and 37 subjects with moderate dry eye (33 women and 4 men with a mean age of 36.4 +/- 12.9 years) completed a 42-item dry eye questionnaire. Seventeen healthy subjects (11 women and 6 men with a mean age of 30.5 +/- 9.7 years) and 28 subjects with moderate dry eye (24 women and 4 men with a mean age of 38.50 +/- 3.8 years) underwent additional objective assessment of ocular surface health, tear osmolality, tear stability, and tear volume.

RESULTS

Subjects with moderate dry eye scored significantly higher (49.8 +/- 20.3, P<0.0001) on the dry eye questionnaire than did normal subjects (11.7 +/- 10.3). Ocular irritation symptoms worsened with progression of time of day in both groups of subjects. Internal reliability (0.95 Cronbach alpha) was excellent, and concurrent validity (Spearman rho 0.507) was acceptable when compared to the McMonnies and Ho dry eye questionnaire. Significant differences in tear osmolality (P<0.00001), invasive tear breakup time (P<0.034), and corneal vital dye staining (P<0.0001) were detected between the two groups of subjects. A stepwise linear regression on objective clinical tests, however, did not account for 77% of the total variance in the questionnaire scores.

CONCLUSIONS

A unique scoring system-based dry eye questionnaire was validated to separate non-contact lens wearers with moderate dry eye from healthy subjects. Objective tests of tear osmolality and stability and ocular surface integrity were better than other clinical measures at identifying differences between the two subject groups. The results strongly support the evidence that the diagnosis and treatment of moderate dry eye requires a detailed assessment of self-perceived symptoms and that objective clinical testing alone may be insufficient.

The Lack of Association Between Signs and Symptoms in Patients With Dry Eye Disease

BACKGROUND

The purpose of this report was to examine the relation between clinical tests and dry eye symptoms in patients with dry eye disease.

METHODS

Seventy-five patients with dry eye disease (ICD-9 code 375.15) were included in these analyses. There was no specific entry criterion for enrollment in addition to a previous dry eye diagnosis in this clinic-based sample. Patients represented varying types and severity of dry eye disease and were previously diagnosed by clinic attending doctors in this university clinic setting. The study examination included a symptom interview that assessed dryness, grittiness, soreness, redness, and ocular fatigue. The interview was followed by a clinical dry eye examination conducted in the following sequence: meibomian gland assessment, tear meniscus height, tear breakup time test, fluorescein staining, the phenol red thread test, Schirmer test, and rose bengal staining. Partial Spearman correlation coefficients, the Wilcoxon rank sum test, chi 2 test, and multivariate logistic regression were used to evaluate the relationship between dry eye tests and symptoms.

RESULTS

Symptoms were generally not associated with clinical signs in patients with dry eye disease. There were no significant correlations between signs and symptoms after adjustment for age and artificial tear use. The rank of each clinical test result did not statistically differ when stratified by the presence of patient symptoms in Wilcoxon rank sum analyses. Likewise, the frequency of patient symptoms did not differ statistically when stratified by a positive clinical test result in chi 2 analyses. In multivariate logistic regression analyses, no clinical test significantly predicted frequently reported symptoms after adjustment for age and artificial tear use.

CONCLUSIONS

These results suggest a poor relation between dry eye tests and symptoms, which represents a quandary in dry eye clinical research and practice.

The Reliability and Validity of McMonnies Dry Eye Index

OBJECTIVE

The purpose of this report was to investigate the psychometric properties of the McMonnies questionnaire for dry eye disease.

METHODS

The instrument was administered to 75 patients with dry eye disease on two occasions. Additional dry eye clinical tests, patient-reported dry eye interviews, and the NEI-VFQ-25 were completed during these examinations. Reliability (internal consistency and test-retest), validity (concurrent and discriminant), and accuracy were assessed for McMonnies Index scores.

RESULTS

McMonnies Index showed poor internal consistency (Cronbach alpha = 0.43) and moderate test-retest reliability (ICC = 0.86, 95% confidence interval 0.76 to 0.90). The mean difference between visits was 0.49 (1-sample t test, t = 0.92, P = 0.36), and the 95% limits of agreement for test-retest reliability were -8.6 to +9.6. The instrument also showed fair concurrent validity, correlating only with the NEI-VFQ-25 pain subscale, but better discriminant validity when comparing mild and severe patients. Finally, the McMonnies Index demonstrated fair accuracy in identifying severe dry eye patients as defined by signs and symptoms (area under the ROC curve = 0.65).

CONCLUSIONS

The McMonnies Index demonstrates fair reliably and validity as a patient-reported instrument for use in patient care and clinical studies of patients with dry eye disease.