Clinical evaluation of meibomian gland dysfunction in patients with keratoconus

PurposeTo investigate the association of keratoconus (KC) with meibomian gland dysfunction (MGD) and to describe the epidemiological characteristics of MGD in this disease.MethodsIn this observational study, 120 KC patients seen in the Department of Ophthalmology of the Complexo Hospitalario Universitario de Santiago de Compostela and 87 controls were analyzed. The Ocular surface disease index (OSDI) questionnaire was administered and several DED tests and an evaluation of the meibomian glands and lid margin were performed. MGD signs and DED tests were compared between the groups. Symptoms were further analyzed in patients and controls with and without MGD.ResultsKC was significantly associated with MGD after adjusting for age and sex [adjusted odds ratio (ORa), 2.40]. The frequency of MGD in KC patients [59 (49.2%) KC patients and 25 (28.7%) controls had MGD] correlated with the severity of KC (r = 0.206) (P = 0.020). Mean OSDI score in KC patients with and without MGD was 31.1 ± 24.1 and 35.2 ± 26.0 (P = 0.326), and 17.2 ± 22.7 and 13.3 ± 14.1 in controls with and without it (P = 0.366). The most common MGD signs coincided in both groups. Staining with fluorescein (P = 0.000) and lissamine green (P = 0.019) was higher in KC patients, but no differences were detected with TBUT (P = 0.116) or the Schirmer test (P = 0.637). Hypersecretory MGD was the most prevalent variant in both groups.ConclusionsMGD and DED are common in KC patients. MGD correlates with the severity of KC and is indistinguishable from MGD in patients without KC. No association was found with symptoms. Patients with KC should be screened for MGD because of its possible clinical implications. Further research is needed to clarify the role of MGD in KC patients.     

The influence of meibomian gland loss on ocular surface clinical parameters

PurposeTo assess the relationship between the meibomian gland loss (MGL) and relevant ocular surface clinical parameters as well as the influence of age in this relationship.MethodsA total of 161 participants (mean age; 42±17 years) were enrolled in this study. Infrared meibography was performed using Keratograph 5M (K5M; Oculus GmbH, Wetzlar). Participants were divided into five groups according to total meiboscore and the ocular surface parameters of each MGL group were studied. In addition, the relationship between MGL and the ocular surface parameters was established including age as covariant.ResultsBoth eyelids were taken into account since no association between the MGL from upper and lower eyelid was found (k value=0.2; p=0.3) despite they were significantly correlated (r= 0.3; p<0.001). No statistically significant differences were found in symptomatology among different MGL groups. Statistically significant differences were found among MGL groups in tear osmolarity (p=0.02), bulbar redness (p=0.04), corneal and conjunctival staining (p=0.01 and p=0.004, respectively). Despite this, only corneal staining showed a significant correlation with MGL when age was covariant (r=0.2; p=0.04).ConclusionsMGL higher than 50% seems to be accompanied by signs on the ocular surface. Furthermore, age demonstrated to be a relevant factor when assessing MGL. For this reason, future studies should compare age-matched groups in order to know the contribution of the MGL on the ocular surface and establish valid cut-off values for dry eye diagnosis.     

Dry eye and Meibomian gland dysfunction with meibography in patients with lamellar ichthyosis

Purpose

To evaluate the dry eye findings and Meibomian gland dysfunction as demonstrated with meibography in patients with lamellar ichthyosis.

Therapeutic profile of a latent heat eyelid warming device with temperature setting variation

PurposeTo compare the effects on ocular temperature and tear film parameters following a single application of a latent heat eyelid warming device at a range of temperature settings.MethodsFifteen subjects were enrolled in a prospective, investigator-masked, randomised, cross-over trial. On separate days, participants were randomised to 10-minute application of a research latent heat device (Laboratoires Théa) at device temperature settings of 45 °C, 50 °C and 55 °C. Outer eyelid and corneal temperatures, tear film lipid layer grade, and non-invasive tear film breakup time (NIBUT) were measured at baseline and immediately after 10 min of device application.ResultsBaseline measurements did not differ between treatment groups (all p > 0.05). Ocular temperatures, lipid layer grade and non-invasive tear film stability rose significantly following device application in all treatment groups (all p < 0.05). The 55 °C setting effected a mean ocular surface temperature rise in the order of +4 °C from baseline, which was 1.46 and 1.26 times greater than at the 45 °C and 50 °C temperature settings, respectively (all p < 0.05). Similarly, improvements in mean non-invasive tear film stability from baseline in the order of +7 s were observed, which were 2.43 and 1.66 times greater than those at the lower temperature settings of 45 °C and 50 °C, respectively (all p < 0.05).ConclusionsAt all temperature settings, the latent heat device resulted in clinically and statistically significant increases in ocular temperature, lipid layer grade, and non-invasive tear film stability. However, the 55 °C setting proved to be most effective at raising ocular temperature (in the order of +4 °C from baseline) and improving tear film stability.     

Evaluation of dry eye disase and meibomian gland dysfunction with meibography in seborrheic dermatitis

PurposeTo evaluate the dry eye disase and meibomian gland dysfunction with meibography of Seborrheic Dermatit patients.MethodsA hundred-ten of 50 patients with Seborrheic Dermatitis (group 1) and 100 eyes of 50 healthy individuals (group 2) were enrolled in this prospective study. All subjects were performed a comprehensive ophthalmic examination including lid margin alterations and meibomian gland obstruction assessment, Ocular Surface Disease Index assessment, tear film break-up time test, corneal and conjunctival fluorescein staining assessment, Schirmer test. In addition, upper and lower lids were evaluated for meibomian gland loss with non-contact meibography. The Meibomian glands were graded from grade 0 (no loss of Meibomian glands) to grade 3 (gland loss >2/3 of the total Meibomian glands).ResultsThe mean ages of Group 1 and Group 2 were 29.1 ± 9.1(range, 18–48) and 30.6 ± 6.3(range, 20–49) years, respectively. MGD(n = 19, %34.5), Meibium gland loss(%36.4 ± 18.1), upper meiboscore (0.7 ± 0.8), lower meiboscore(0.6 ± 0.7) and DED (n = 10, %18.2) were significantly higher in the SD patients compared with the control participants (p = 0.002, p < 0.001, p = 0.011, p = 0.005, p = 0.048, respectively). There was significant relationship between age with Meibomian gland loss, MGD and DED (p = 0.017, p = 0.004, p = 0.002, respectively).ConclusionsSeborrheic Dermatitis may influence meibomian gland morphology and as a result causing meibomian gland dysfunction and dry eye disase. For this reason, patients with Seborrheic Dermatitis should be evaluated for meibomian gland dysfunction and dry eye disase, and start treatment when needed.     

Effect of meibomian gland morphology on functionality with applied treatment

PurposeTo determine how Meibomian gland (MG) morphology affects MG function by means of gland expression with the effect of treatment.MethodsFifteen patients (aged 31.6 ± 13.1 years) from a dry eye clinic diagnosed with MG dysfunction had their 365 lower lid MGs visualised with a slit-lamp biomicroscopy. Using infrared meibography (Oculus K5m), MG length, width and tortuosity were objectively measured. Each MG was expressed and the meibum graded (0=clear fluid, 1=cloudy fluid, 2= particulate fluid, 3=inspissated, or 4 = no expression) to determine its functionality. Participants had functionality repeated each time following a sequence of a warm compress, debridement, and forcible expression after 5 min.ResultsJust over 10 % of complete length MGs gave clear expression, while about 5% did not express at all, with most expressed meibum being particulate in nature. In contrast, the majority of partial length glands gave inspissated expression (38 %), with 32 % not expressing at all. No MG of <10 % length expressed. MG gland length was correlated with gland expression (r=?0.507, p < 0.001) and MG tortuosity (r=?0.129, p < 0.001), but not MG width (r=?0.090, p = 0.167). Regardless of MG length, warm compress increased the quality of expression (p < 0.002). Debridement further improved expression in partial MGs (p = 0.003), but not forcible expression (p = 0.529).ConclusionsLength is the key functional morphology metric of lower lid MGs. Warm compress and massage increase the quality of expression in all, but the shortest glands and patients with partial length glands also benefit from debridement.     

Evaluation of the tear clearance rate by dacryoscintigraphy in patients with obstructive meibomian gland dysfunction

PurposeTo measure tear clearance values in patients with meibomian gland dysfunction (MGD) with a dynamic nuclear medicine method, namely, dacryoscintigraphy (DSCI).MethodsTwenty-four MGD patients and 24 healthy volunteers were examined. During DSCI one drop of a solution with 100 MBq/mL^99mTc sodium pertechnetate was instilled with a micropipette into the lacrimal lake of both eyes. Measurements were performed according to a dynamic data acquisition protocol, which resulted in summed DSCI images. Data were also evaluated separately in special regions of interest (ROI), and consecutive time activity curves were created. Tear clearance (T½) values were calculated based on the activity curves. In addition, tear osmolarity measurements, tear breakup time (tBUT), and Schirmer I (ST_I) tests were performed prior to DSCI examination.ResultsThe T½ values were 29.91 ± 11.61 min in MGD patients and 6.26 ± 1.5 min in healthy controls. Tear osmolarity parameters were 308 ± 9.41 mOsm/L and 288.9 ± 6.4 mOsm/L, tBUT values were 5.54 ± 2.73 s and 11.4 ± 2.7 s, while the ST_I test values were 6.17 ± 2.78 mm and 13.58 ± 3.8 mm, respectively. The differences were significant (p < 0.01) in all cases.ConclusionsAlthough the MGD patients’ lacrimal drainage systems were patent their tear clearance values were significantly higher than those of healthy volunteers, which may be caused by decreased drainage of tears from the eyes towards the nasal cavity. The understanding of new features regarding the altered physico-chemical characteristics of MGD tears has been augmented by the results of this study.     

Comparison of meibomian gland dropout using two infrared imaging devices

PurposeTo measure the degree of meibomian gland (MG) dropout in the lower eyelid determined by analysis of images obtained from the LipiView II (LVII) and the Keratograph 5M (K5M).MethodsThe inferior eyelid of each participant was imaged in a random order using both devices. All images were subjectively assessed by a single-masked investigator to determine the extent of MG loss using the Arita 4-point meiboscore grading scale. The images were also semi-objectively analyzed with ImageJ to calculate the percentage of MG dropout, by tracing around the non-glandular area and the total exposed area of the lower lid.ResultsTwenty participants (mean age 37 years, range 23–60, 60% female) completed the study. A significant difference in meiboscore (mean ± SD) was obtained between the LVII and the K5M (1.43 ± 0.78 vs. 1.90 ± 0.81, Z = 3.25, p = 0.001). The meiboscore 95% limit of agreement (LOA) ranged from −1.88 to +0.93. A significant difference was found with mean ImageJ percentage dropout between the LVII and the K5M (31.5% vs 43.4%, t = −4.8, p = 0.00003). The percentage dropout 95% LOA ranged from −42.79% to +19.06%.ConclusionsLVII images had significantly lower meiboscores and less percentage MG dropout. Varying amounts of dropout were observed between the devices due the amount of eyelid that was typically everted and because of differences in image quality. These results indicate that these devices should not be used interchangeably to evaluate MG dropout.     

Changes in the expression of matrix metalloproteinase-9 after intense pulsed light therapy combined with meibomian gland expression in moderate and severe meibomian gland dysfunction

PurposeTo evaluate the combined effect of intense pulsed light (IPL) therapy and meibomian gland expression on extracellular matrix metalloproteinase-9 (MMP-9) levels and clinical outcomes of moderate and severe meibomian gland dysfunction (MGD) treatment.MethodsThis retrospective study was conducted on 45 eyes of 23 patients with moderate and severe MGD. Each eye underwent three IPL sessions and meibomian gland expression at 2-week intervals. In this study the evaluated parameters included tear film break-up time (TBUT), corneal and conjunctival fluorescein staining scores, biomicroscopic examination of lid margins and meibomian glands, ocular surface disease index (OSDI) questionnaire score, and extracellular MMP-9 levels using the immunoassay device before and two weeks after the last treatment session. Linear mixed model and generalized estimating equations model were used to evaluate possible differences.ResultsThere were significant improvements in TBUT (P < 0.001), SICCA ocular staining score (P = 0.008), Oxford staining score (P = 0.023), lid margin irregularity (P < 0.001 for upper and lower eyelids), lid thickness (P < 0.001 for upper and lower eyelids), meibomian gland plugging (P = 0.010 and P = 0.012 for upper and lower eyelids), meibum color (P = 0.044 and P < 0.001 for upper and lower eyelids), meibum consistency (P < 0.001 for upper and lower eyelids), MGD grade (P < 0.001), and OSDI questionnaire score (P < 0.001). Incidence of positive results for MMP-9 immunoassay significantly decreased from 84.0% to 56.0% (P = 0.031) after treatment.ConclusionIn patients with moderate to severe MGD, three sessions of IPL combined with meibomian gland expression improved objective findings, subjective symptoms, meibomian gland function, and MMP-9 immunoassay results. The results support the combination of IPL and meibomian gland expression for treating moderate to severe MGD.     

Investigating the subjective cooling effect of eyelid cleansing gel on eyelid and ocular surface temperature

PurposeTo investigate if the application of Blephagel, an eyelid cleansing gel, causes subjective and/or objective cooling effects by measuring ocular symptomology and temperature.MethodsTwenty-five healthy subjects underwent baseline non-invasive temperature measurements on the closed upper eyelid (centrally, nasally, and temporally) and ocular surface temperature (OST) on both eyes using an infrared camera. A standard application of Blephagel was then applied to the closed upper eyelid and eyelashes with a sterile cotton-wool to one eye selected at random. Temperature measures were then repeated on both eyes after 30–60, 120–150, and 180–210 s. At each interval, subjects rated the comfort and any cooling sensation of each eye on a 0–10 scale.ResultsAfter application of the gel, there was a significant difference in temperature at all locations on the eyelid between the test and control eyes over time (F = 9.322, p < 0.001). Post hoc analysis revealed this was significant from 30 to 60 s interval (36.3 ± 1.1 °C versus 37.2 ± 0.7 °C; p < 0.001) and the 120–150 s interval (36.8 ± 0.8 °C versus 37.2 ± 0.6 °C; p < 0.001). There was no significant variation between the OST locations over time (F = 3.350, p = 0.07). With respect to symptoms, there was a significant increase in cooling sensation in the test eye compared to the control eye over time (F = 10.438, p < 0.001), that remained throughout the experiment.ConclusionsBlephagel produces a reduction in temperature of the eyelids that is accompanied with a subjective cooling sensation.     

Comparison of treatment effect across varying severities of meibomian gland dropout

Purpose

Better understanding of the pathophysiology of meibomian gland dysfunction (MGD) has provided the opportunity to develop treatments which could be tailored for specific presentations of MGD. This study sought to directly compare treatment effectiveness for three current therapies across differing levels of MG dropout.

Screening utility of a rapid non-invasive dry eye assessment algorithm

PurposeTo evaluate the discriminative ability of a rapid non-invasive dry eye assessment algorithm (global evaluation component: SANDE questionnaire, and non-invasive tear film breakup time; subtype classification testing component: tear film lipid layer grade, and tear meniscus height) in detecting dry eye disease, as defined by the TFOS DEWS II diagnostic criteria.MethodsTwo hundred and thirty-five participants (77 male, 158 female), with a mean ± SD age of 43 ± 17 years, were recruited into a prospective diagnostic accuracy study. OSDI, DEQ-5, and SANDE dry eye symptomology scores; non-invasive tear film breakup time; absolute and inter-ocular differences in tear osmolarity; corneal, conjunctival, and lid margin staining scores; tear film lipid layer, meibum expressibility, meibomian gland orifice plugging, and eyelid margin telangiectasia grades; and tear meniscus height were evaluated in a single clinical session.ResultsThe areas under the ROC curves exceeded 0.80 for all individual components of the rapid non-invasive dry eye assessment algorithm, and the discriminative abilities were significantly greater than chance (all p < 0.001). At the Youden optimal diagnostic thresholds for the global evaluation component of the rapid non-invasive assessment algorithm (SANDE score ≥30, non-invasive tear film break-up time <10 s), the overall sensitivity was 86%, specificity 94%, positive likelihood ratio 15.0, and negative likelihood ratio 0.15.ConclusionsThe abridged non-invasive dry eye assessment algorithm may be a useful rapid screening instrument for the full TFOS DEWS II diagnostic test battery, of particular benefit in resource or time-constrained settings.     

Rationale for 24-hour management of dry eye disease: A review

The symptom severity of patients with dry eye disease (DED) varies over a 24-hour period. It is typically worse upon waking than later in the morning and deteriorates towards the evening. Substantial differences in the characteristics and physical properties of the tear film, such as levels of inflammation, pH, osmolarity, volume and stability, also exist between night (sleeping) and day (waking), and over the course of the day itself. Data on diurnal variation in symptom severity and tear film characteristics have been reviewed to recommend a management strategy that supports the various needs of patients with DED over a full 24-hour period.Treatment strategies for DED must be matched to the variations in the severity of DED and to the environments that eyes are subjected to over a 24-hour period. While artificial tears are used to moisturise the ocular surface and reduce damage to the corneal epithelium during the day, gels are used at night-time; they are more viscous and have a longer ocular surface retention time than artificial tears. Several combinations of these products are currently available in tandem to support the 24-hour variation in tear film characteristics. The present review of published literature provides evidence that the approach of the daytime use of artificial tears to protect the eye from aggravating environmental factors in combination with the night-time use of gels to relieve more severe symptomatology. This, in turn, should provide optimal ‘around-the-clock’ DED management.     

Modifiable lifestyle risk factors for dry eye disease

PurposeTo examine the association between modifiable lifestyle factors and dry eye disease.MethodsThree hundred and twenty-two community residents (186 females, 136 males; mean ± SD age, 41 ± 22 years) with no major systemic or ophthalmic conditions (other than dry eye disease) were recruited in a cross-sectional study. A lifestyle factor questionnaire was administered, and dry eye symptomology, ocular surface characteristics, and tear film quality were evaluated for each participant within a single clinical session, in accordance with the global consensus recommendations of the TFOS DEWS II reports.ResultsA total of 111 (34 %) participants fulfilled the TFOS DEWS II diagnostic criteria for dry eye disease. Multivariate regression analysis demonstrated that advancing age, female sex, East Asian ethnicity, and increased digital screen exposure time were positive risk factors for dry eye disease (all p < 0.05), while increased caffeine consumption was a protective factor (p = 0.04).ConclusionsIncreased digital screen exposure time and reduced caffeine consumption were modifiable lifestyle factors associated with higher odds of dry eye disease. These findings might contribute to informing the design of future prospective research investigating the efficacy of preventative intervention and risk factor modification strategies.     

Long-term effects of intense pulsed light treatment on the ocular surface in patients with rosacea-associated meibomian gland dysfunction

Purpose

We aimed to determine the long-term effects of intense pulsed light (IPL) treatment in rosacea-associated meibomian gland dysfunction (MGD).

Short-term tolerability of commercial eyelid cleansers: A randomised crossover study

PurposeTo evaluate the short-term tolerability of five commercially available anti-demodectic eyelid cleansers; OCuSOFT Oust Demodex (OD), I-MED I-Lid’n Lash Plus (ILL+), Labtician BlephaDex (BD), Chrissanthe Eye Cleanse (EC), and Théa Blephademodex (BDdx).MethodsThirty healthy non-contact lens wearers (18 female; mean ± SD age, 33 ± 12 years) were enrolled in a prospective randomised crossover study. On separate visits, spaced at least 48 h apart, participants were randomised to receive topical application of one of five eyelid cleansers or saline. Participants rated subjective ocular discomfort during the 10-minute post-application period. Visual acuity, non-invasive tear film stability, conjunctival hyperaemia, and ocular surface staining were assessed at baseline and 10 min.ResultsNo inter-group differences in ocular parameters were noted at baseline (all p > 0.05). Ocular discomfort scores significantly exceeded baseline scores for 60 s following BD application, 120 s with OD, 135 s with BDdx, 150 s with ILL+, and 195 s with EC (all p < 0.05). Deterioration in non-invasive tear film stability, limbal conjunctival hyperaemia, as well as corneal, conjunctival, and lid margin staining was detected following EC application (all p < 0.05), and increased bulbar conjunctival hyperaemia was observed following both EC and ILL+ treatment (both p < 0.05).ConclusionsStudy outcomes highlight varying tolerability profiles with different anti-demodectic lid cleanser preparations, and the potential to induce tear film instability, conjunctival hyperaemia and ocular surface staining on application. Awareness of possible adverse effects arising from topical application of commercial anti-demodectic lid cleanser formulations may help clinicians set realistic patient expectations and encourage better compliance in their use of lid hygiene therapies.     

Effect of virtual reality headset wear on the tear film: A randomised crossover study

PurposeTo compare the effects of virtual reality headset wear and conventional desktop computer display use on ocular surface and tear film parameters.MethodsTwenty computer operators were enrolled in a prospective, investigator-masked, randomised crossover study. On separate days, participants were randomised to 40 min of continuous virtual reality headset wear or conventional desktop computer display use. Outer eyelid and corneal temperatures, tear film lipid layer grade, and non-invasive tear film breakup time were measured at baseline and immediately following the 40-minute exposure period.ResultsVirtual reality headset wear resulted in increases in outer eyelid (mean difference +0.5 ± 0.6 °C; p < 0.001) and corneal temperatures (mean difference, +0.4 ± 0.6 °C; p = 0.004), relative to conventional desktop computer display use. These increases were associated with significant improvements in tear film lipid layer grade (median difference, +1 grade; interquartile range, 0 to +2 grades; p < 0.001) and non-invasive tear film breakup time (mean difference, +7.2 ± 12.4 s; p = 0.02).ConclusionsClinically significant improvements in lipid layer thickness and tear film stability were observed with virtual reality headset wear, despite producing only modest increases in ocular temperatures relative to conventional desktop computer display use. These findings would suggest that virtual reality headset wear demonstrates potential for dry eye relief for computer operators in the modern workplace environment.     

Effect of the Bruder moist heat eye compress on contact lens discomfort in contact lens wearers: An open-label randomized clinical trial

The purpose of this study was to investigate the effect of the Bruder Moist Heat Compress on contact lens (CL) discomfort in subjects with contact lens-related dry eye (CLDE). This was a 4-week, single-center, three-arm, randomized, open-label clinical trial in subjects diagnosed with CLDE using the Contact Lens Dry Eye Questionnaire. Fifty-one CL wearers were randomized to one of three treatment groups: application of the Bruder Compress twice a day, Bruder Compress once a day, or warm washcloth used for ten minutes twice a day without reheating. Subject diaries were monitored for compliance and collected data on daily CL comfort upon awakening and throughout the afternoon. Clinical assessments included tear film break-up time (TBUT), lipid layer thickness (LLT), and meibomian gland evaluation. Statistical tests included a generalized linear model and one-way analysis of variance (ANOVA) to investigate treatment effect on comfortable wear time.Fifty-one subjects (98% female) completed the study. After treatment, subjects using a washcloth reported more uncomfortable contact lens wear time on average (mean = 5.1 ± 2.8 h) when compared with subjects who had used the Bruder Compress in Group 1 (mean = 2.8 ± 1.6 h) (p = 0.02). In the Bruder Compress groups, there was a significant reduction in the blockage of meibomian glands (p < 0.01). No significant difference in uncomfortable wear time was found between subjects using the Bruder Compress twice daily versus once daily (p = 0.48). Subjects using the Bruder Compress once daily had the highest rate of compliance at 90.2% (p < 0.01). No significant improvements were observed in TBUT (p = 0.76) or LLT (p = 0.78).The Bruder Moist Heat Compress resulted in a significant improvement in comfortable CL wear time in subjects with CLDE.     

Assessment of four validated questionnaires for screening of dry eye disease in an African cohort

PurposeTo evaluate the 5-item dry eye questionnaire (DEQ-5) for measurement precision and unidimensionality, and assess the ability of Ocular Surface Disease Index (OSDI), McMonnies Dry Eye Questionnaire (MQ), Ocular Comfort Index questionnaires (OCI), and DEQ to predict clinical measures of DED in an African population.MethodParticipants (n = 113; mean age 24.7 ± 5.4 years) completed all four questionnaires administered in a randomized order. Internal consistency and test-retest reliability of the instruments were assessed. A masked examiner performed clinical dry eye tests in both eyes of participants and the results used to classify into either “dry” or “non-dry” groups. The diagnostic criteria for dry eye disease were tear break up time (TBUT) < 10 s plus at least one of Schirmer <15 mm in 5 min., > 5 corneal staining spot, or > 9 conjunctival staining spots. Rasch analysis was performed to assess the DEQ for unidimensionality and measurement precision, and receiver operating characteristic curve (AUC) analysis was used to assess the ability of the four questionnaires to predict clinical measures of DED.ResultsThe responses from the DEQ-5 met the Rasch analysis criterion of unidimensionality with infit and outfit values of between 0.74–1.43 mean-square and 0.69–1.49 mean-square, respectively, and measurement precision of 2.33. Internal consistency and test-retest reliability of each test was high, with Cronbach alpha >0.70 for the questionnaire and their respective subscales but internal consistency reliability of the MQ was poor (Cronbach’s alpha = 0 .29?0 0.52). Each test segregated the “dry” and “non-dry” groups with moderate (all AUC 0.70?0.80) and similar accuracy (P > .05).ConclusionThe DEQ -5 demonstrated adequate measurement precision and unidimensionality. Each of the four questionnaires showed psychometric validity for clinical use in the African population, and modest and similar accuracy when screening for dry eye signs but the performance of the McMonnies questionnaire was limited in terms of internal consistency reliability.