Clinical observation of tear film breakup time with a novel smartphone-attachable technology

PURPOSE

To demonstrate the practicability of a portable instrument in assessing tear film breakup time (TFBUT): a lens attachment for smartphones (LAS).

METHODS

By applying LAS in combination with the iPhone 12 pro, and a recordable slit-lamp microscope, we obtained TFBUT videos from 58 volunteers. The comparison between the conventional slit-lamp microscope and LAS by an experienced ophthalmologist. Moreover, we also invited an ophthalmic postgraduate student and an undergraduate student with no clinical experience to assess TFBUT in those videos. The inter-observer reliability was assessed using intraclass correlation coefficients (ICC).

RESULTS

The TFBUT of 116 eyes in total was recorded. Reliability indexes were adequate. The Spearman's correlation analysis and the intraclass correlation coefficient suggested a strong correlation between the 2 modalities (Right eye: Spearman's r = 0.929, 95% confidence interval (CI) = 0.847-0.963, ICC = 0.978, p < 0.001; Left eye: Spearman's r = 0.931, 95% CI = 0.866-0.964, ICC = 0.985, p < 0.001;). Between instruments, the majority of TFBUT measurements showed good agreement on Bland Altman plot. A high concordance was observed in TFBUT, when assessed by an ophthalmologist and an ophthalmic postgraduate student (Left eye: LAS ICC = 0.951, p < 0.001; Left eye: slit-lamp microscope ICC = 0.944, p < 0.001).

CONCLUSIONS

Compared with the conventional slit-lamp microscope, the LAS has sufficient validity for evaluating TFBUT in clinics or at home.

Morphological alterations in corneal nerves of patients with dry eye and associated biomarkers

The purposes of the present study were to (1) identify the relationship between dry eye symptoms and morphological changes in corneal subbasal nerves/ocular surfaces, and (2) discover tear film biomarkers indicating morphological changes in the subbasal nerves. This was a prospective cross-sectional study conducted between October and November 2017. Adults with dry eye disease (DED, n = 43) and healthy eyes (n = 16) were evaluated based on their subjective symptoms and ophthalmological findings. Corneal subbasal nerves were observed using confocal laser scanning microscopy. Nerve lengths, densities, branch numbers, and nerve fiber tortuosity were analyzed using ACCMetrics and CCMetrics image analysis systems; tear proteins were quantified by mass spectroscopy. Compared with the control group, the DED group had significantly lower tear breakup times (TBUT) and pain tolerance capacity, and significantly higher corneal nerve branch density (CNBD) and corneal nerve total branch density (CTBD). CNBD and CTBD showed significant negative correlations with TBUT. Six biomarkers (cystatin-S, immunoglobulin kappa constant, neutrophil gelatinase-associated lipocalin, profilin-1, protein S100-A8, and protein S100-A9) showed significant positive correlations with CNBD and CTBD. The significantly higher CNBD and CTBD in the DED group suggests that DED is associated with morphological alterations in corneal nerves. The correlation of TBUT with CNBD and CTBD further supports this inference. Six candidate biomarkers that correlate with morphological changes were identified. Thus, morphological changes in corneal nerves are a hallmark of DED, and confocal microscopy may help in the diagnosis and treatment of dry eyes.

Non-invasive evaluation of meibomian gland morphology and tear film and anterior segment parameters in women with polycystic ovarian syndrome

PURPOSE

To compare the meibomian glands (MG), non-invasive tear film break-up time (NITBUT), and corneal and anterior segment measurements in patients with polycystic ovary syndrome and healthy women.

METHODS

The study included 66 polycystic ovarian syndrome (PCOS) patients and 42 healthy volunteers aged 18-35 years. The first and average NITBUT, MG loss, mean keratometry (Km), central (CCT) and thinnest (TCT) corneal thicknesses, anterior chamber depth (ACD), anterior chamber volume (ACV), irido-corneal angle (ICA), corneal volume (CV) and Ocular Surface Disease Index (OSDI) results were analyzed.

RESULTS

The mean MG loss values were 29.9 ± 11.9 and 20.8 ± 11.0 in the PCOS and control groups, respectively (p < 0.001). MG loss (meiboscale ≥ 1) was determined in 64 (96.9%) eyes in the PCOS group and in 36 (85.7%) eyes in the control group. There was no significant difference between the groups in respect of NITBUT, OSDI, Km, CCT, TCT, ACD, ACV, ICA and CV values (p > 0.05, for all).

CONCLUSION

MG loss is a physiological process which is distinct in PCOS patients, but does not cause tear film alterations. Further studies are needed to show the contributing factors of MGD in PCOS patients.

Clinical comparison of tear film breakup time measurements in normal dogs using three different methods of fluorescein solution administration

OBJECTIVE

To evaluate whether the method of fluorescein administration affects the results of tear film breakup time (TFBUT) measurement in normal dogs.

ANIMALS STUDIED

Thirty-seven client and hospital staff owned dogs over 1 year of age with no known comorbidities or administration of systemic or topical ophthalmic medications.

PROCEDURES

A prospective randomized three-way crossover study was conducted. All dogs received an abbreviated ophthalmic examination to rule out ocular surface disease. Using a 30-min washout interval period, each dog's right eye was received: (a) direct application of fluorescein stain strip with one drop of sterile eyewash, (b) direct application of fluorescein stain strip with two drops of sterile eyewash, or (c) application of one drop from a premade fluorescein solution (dilution of one strip in 0.3 mL sterile eyewash). Eyes were assessed using the cobalt blue filter of a slit lamp biomicroscope. TFBUT measurements were summarized as means ± standard deviation. The methods were compared using mixed model analysis of variance. All analyses were performed using sas version 9.4.

RESULTS

Thirty-seven dogs met the inclusion criteria. Mean TFBUT ± standard deviation (SD) for the three described methods were: (a) 16.58s ± 6.9, (b) 15.98s ± 7.1, and (c) 16.43s ± 8.1. No differences between fluorescein stain application techniques were observed (p = .92).

CONCLUSION

The technique of fluorescein solution administration did not affect TFBUT measurement in this population of healthy dogs.

Effects of cataract surgery on symptoms and findings of dry eye in subjects with and without preexisting dry eye

PURPOSE

To compare dry eye symptoms and findings in post cataract surgery eyes' with and without preexisting dry eye.

STUDY DESIGN

Prospective, observational case-control study.

METHODS

Sixty-seven eyes that had undergone cataract surgery were included; 48 were classified into group D (preexisting dry eye) and 19 into group N (no preexisting dry eye). No subjects received perioperative treatment for dry eye. We evaluated between-group differences in symptom scores, corrected distance visual acuity (CDVA), tear film breakup time (BUT), tear film breakup pattern (BUP), and ocular surface fluorescein staining scores, at 1 week, 1 month, and 3 months postoperatively.

RESULTS

Symptoms were unchanged in group N, but improved in group D (P < .001) postoperatively. CDVA was improved after surgery in both groups (P < .001). BUT was shorter preoperatively in group D than in group N although this difference was absent 1 month postoperatively. Fluorescein staining scores significantly increased at 1 month postoperatively in group N (P = .01), but did not change in group D. During the perioperative period, the predominant BUP was the random break pattern in both groups (≥ 85%). From 1 week to 3 months, dimple break patterns decreased in group D (P = .007), whereas spot break patterns increased (P = .01).

CONCLUSIONS

Cataract surgery has an influence on tear film stability and the ocular surface. There was either a transient improvement or worsening of ocular surface wettability in some patients without preexisting dry eye.

A Multicenter Study of the Prevalence of Dry Eye Disease in Chinese Refractive Surgery Candidates

OBJECTIVE

The aim of this study was to determine the prevalence of preoperative dry eye disease and evaluate tear film function in refractive surgery candidates in China.

METHODS

In this prospective noninterventional cross-sectional study, refractive surgical candidates from 13 preselected eye hospitals in China were recruited from July 2015 to February 2016. Patient histories, subjective symptoms, tear film breakup time (TBUT), ocular surface fluorescein staining, and Schirmer I tests (SIT), were assessed to conduct subgroup analysis.

RESULTS

A total of 1,849 patients were recruited, 41.4% were diagnosed with dry eye disease (766/1,849) and 44.9% (830/1,849) of subjects had a positive history of contact lens (CL) wear. The overall mean TBUT and SIT values were 7.3 ± 3.7 s and 15.2 ± 8.8 mm, respectively. The total prevalence of ocular surface fluorescein staining was 23.46% (422/1,849); 44.62% of patients had TBUT <5 s and 23.20% of patients had SIT <5 mm. CL wearers were observed to have a higher prevalence of dry eye than non-CL wearers (54.1 vs. 35.2%, OR = 2.17, 95% CI: 1.77-2.65).

CONCLUSIONS

In this study, the most common abnormal finding in dry eye disease was tear film instability. A high proportion of refractive surgery candidates have preexisting dry eye disease and a history of CL wear prior to surgery. Careful attention should be given to the evaluation of preoperative dry eye in refractive surgery candidates.

The evaluation of dry eye mobile apps for screening of dry eye disease and educational tear event in Japan

PURPOSE

To evaluate the usefulness of a dry eye mobile application (app) for screening dry eye disease (DED) at educational tear events in Japan.

METHODS

In this cross-sectional study, Japanese subjects visiting a "Tears Day" event were selected randomly. They completed questionnaires and underwent ophthalmic evaluations for DED (using Japanese revised diagnostic criteria) including a functional visual acuity (FVA) test. The app calculated FVA using the average of the continuous VA over 30 s.

RESULTS

Sixty-three general-population subjects were included: 25 men and 38 women (average age, 50.8 ± 15.9 years). The prevalence of DED was 66.7% (42 subjects); age was significantly higher among subjects with DED (55.2 ± 3.4 vs. 48.1 ± 2.7 years, p = 0.04; men, 54.0 ± 7.3 vs. 47.0 ± 3.0 years, p = 0.36; women, 55.5 ± 3.9 vs. 50.6 ± 3.8 years, p = 0.4). The prevalence of DED was significantly higher in women (p = 0.04). Tear film breakup time was significantly shorter (3.8 ± 2.4 vs. 8.7 ± 2.0, p = 0.04) and the meibum score was significantly higher (p = 0.02) among subjects with DED. Regarding the tear film breakup pattern, line and random breaks were most prevalent among DED. FVA showed a significant negative correlation with DED (r = -0.25, p = 0.047).

CONCLUSIONS

The app might motivate people to perform quick tests with the expectation of getting easy DED screening. The number of subjects diagnosed with DED was relatively high.