Relation between dry eye and myopia based on tear film breakup time, higher order aberration, choroidal thickness, and axial length

Ocular surface in patients with different degrees of myopia

AIM

To investigate the clinical features of the ocular surface in patients with different degrees of myopia.

METHODS

A cross-sectional study was conducted involving 122 participants with myopia in Beijing Tongren Hospital from February to June, 2023. After completing the Ocular Surface Disease Index (OSDI) score scale, measurements were taken for refraction, biometric parameters and ocular surface parameters. The prevalence, severity and related parameters of the dry eye among different groups based on axial length (AL) were compared. Correlation analysis was performed between ocular surface parameters and refraction/biometric measurement parameters.

RESULTS

Statistically significant differences were observed in refractive error, corneal thickness, anterior chamber depth, and subfoveal choroidal thickness among the groups (all P<0.05). With the increase in AL, the incidence and severity of dry eye increased significantly (P<0.05). Moreover, the tear film break-up time (BUT) shortened (P<0.05), and the corneal fluorescein staining (CFS) points increased significantly (P<0.05). OSDI scores were positively correlated with AL and spherical equivalent (SE; both P<0.05); BUT was negatively correlated with AL, SE, and corneal astigmatism (AST; all P<0.05); Schirmer I test (SIT) results were negatively correlated with AL and SE (both P<0.05).

CONCLUSION

AL elongation is a risk factor for dry eye onset in myopic participants. The longer the AL, the more severe the dry eye is, with the increased CFS spots and tear film instability. Additionally, SE and AST exhibit negative correlations with dry eye symptom scores and ocular surface parameters.

A Possible Reciprocal Relationship Between Myopia and Dry Eye Disease in Japanese Teenagers

Purpose

To investigate the relationship between dry eye disease (DED) and myopia in Japanese teenagers.

Methods

This clinic-based, retrospective, cross-sectional study assessed DED condition in 10- to 19-year-old teenagers presenting at Japanese eye clinics. They included 106 high myopic patients (HM; mean age, 16.4 ± 2.2 years), 494 mild myopic patients (15.0 ± 2.6 years) and 82 non-myopic teenagers (NM; 13.8 ± 2.6 years). Subjective refraction and anisometropia were measured. Myopia grade was classified as HM (≤ -6.00 D), MM (> -6.00 D, < -0.50 D), or NM (≥ -0.5 D). The presence of DED-related symptoms including dryness, irritation, pain, fatigue, blurring and photophobia were assessed through a questionnaire. Tear film break-up time (BUT) and fluorescein corneal staining were investigated. Comparison among three groups and regression analysis of myopic error and other variables were conducted.

Results

Anisometropia and astigmatic error were greatest in the HM group compared with the other groups (p < 0.001). The HM group reported less photophobia (p < 0.001) and less pain (p = 0.039) compared with the NM group. Regression analysis revealed that myopic error was correlated with astigmatic error (β = -0.231, p <0.001), anisometropia (β = -0.191, p <0.001), short BUT (β = -0.086, p = 0.028) and the presence of diagnosed DED (β = -0.112, p = 0.003). Dryness (β = -0.127 p = 0.004), photophobia (β = 0.117, p = 0.002) and pain (β = 0.084, p = 0.034) correlated with myopic error.

Conclusion

This study associated clinical findings of DED in HM teenagers. The present results suggest DED might be associated with myopia, possibly in a reciprocal relationship.

The impact of dry eye disease on retinal image quality in children

BACKGROUND AND OBJECTIVES

Dry eye disease (DED) is increasingly prevalent, resultinginhigher morbidityamong children. This study evaluates the impact of DED severity on visual quality using double-pass technology, focusing on dynamic observation of the ocular light scatter in pediatric DED cases.

METHOD

In this non-interventional, cross-sectional study, a mild DED group (37 cases, 37 eyes), a moderate DED group (40 cases, 40 eyes), and a control group of healthy children (35 cases, 35 eyes) were examined. Measurements included the Schirmer I test, tear film break-up time (BUT), and vision-related quality of life assessments using the Modified Ocular Surface Disease Index (OSDI) questionnaires. Participants underwent visual quality analysis using double-pass technology, which measured the modulation transfer function cut-off frequency value, Strehl ratio, objective scatter index (OSI), and OQAS-II value (OQAS-II value 100%, OQAS-II value 20%, and OQAS-II value 9%) under natural conditions. Additionally, dynamic changes in OSI post-blinking, Tear film mean-OSI , and the corresponding standard deviation OSI were recorded.

RESULTS

Statistically significant differences were observed among the groups in modulation transfer function cutoff, Strehl ratio, OSI, OQAS-II value 100 %, OQAs-II value 20 %, OQAs-II value 9 %, tear film mean OSI, and standard deviation OSI (P < 0.05). As DED severity increased, tear film mean OSI significantly rose, while modulation transfer function cutoff, strehl ratio, OQAS-II value 100 %, OQAS-II value 20 %, OQAS-II value 9 % notably declined. All optical quality parameters were correlated with BUT, with no association observed with age, sex, or Schirmer I test.

CONCLUSION

Dual-channel technology objectively assesses visual quality in pediatric DED, demonstrating that tear film scattering significantly affects retinal imaging and visual quality in children with DED.

Repeatability and agreement of the MYAH and Lenstar

SIGNIFICANCE

Validation of new biometry instruments against the gold standard and establishing repeatability are important before being utilized for clinical and research applications.

PURPOSE

This study aimed to investigate intersession repeatability of the MYAH optical biometer and corneal topographer and examine agreement with the Lenstar LS900 optical biometer in healthy young adults.

METHODS

Forty participants (mean age, 25.2 ± 3.1 years) presented for two visits, 2 to 4 days apart. At each visit, measurements for right eyes were collected with the MYAH and Lenstar LS 900 and included axial length, corneal power, white-to-white distance, and pupil diameter. Bland-Altman analysis was used to assess the intrasession agreement between the MYAH and Lenstar for each parameter and intersession repeatability for the two devices. For each device, coefficient of variation and intraclass correlation coefficient were calculated, and paired t tests between visits were performed to assess intersession repeatability.

RESULTS

Good agreement (mean difference [95% limits of agreement]) between the MYAH and Lenstar was found for axial length (-0.01 [-0.07 to 0.04] mm), corneal power (-0.02 D [-0.15 to 0.19 d]), white-to-white distance (-0.13 [-0.43 to 0.17] mm), and pupil diameter (-0.27 [-0.79 to 1.33] mm). The limits of agreement, coefficient of variations, and intraclass correlation coefficients for MYAH-measured parameters were -0.04 to 0.04, 0.06%, and >0.99 for axial length; -0.24 to 0.19, 0.18%, and >0.99 for corneal power; -1.05 to 1.15, 0.57%, and 0.96 for white-to-white distance; and -0.17 to 0.21, 7.0%, and 0.76 for pupil diameter, with no significant difference between visits (p>0.05 for all), indicating good intersession repeatability. Similar intersession repeatability was also noted for Lenstar.

CONCLUSIONS

Findings show good intersession repeatability of the MYAH and good agreement with the Lenstar for axial length, corneal power, and white-to-white distance in young adults. Pupil diameter was more variable, likely due to the dynamic nature of the pupil. This study provides validation and supports the use of the MYAH for ocular biometry.

Risk of major myopia-associated non-communicable ocular health disorders in Ghana

OBJECTIVE

To assess the differential association of myopia with major non-communicable ocular diseases in an African clinical cohort.

METHODS

A five-year hospital-based retrospective study of myopia cases. Patients' folders, Optical Coherence Tomography scans, and fundus photographs were reviewed for the abstraction of relevant data. Only records that employed recognized standards and classification systems for diagnosing and staging the various ocular conditions were included. Demographic characteristics, non-cycloplegic objective refractive findings, and non-communicable eye diseases were retrieved from the records. Myopia-associated risk factors were then determined using logistic regression and correlation.

RESULTS

Some 16018 patients (32027 eyes) met the inclusion criteria for at least one eye comprising 50.8% males (n = 8137) and 49.2% females (n = 7881). The mean age of the patients was 43.14 ± 17.88 years (range: 2-98 years). The mean spherical equivalent± Standard deviation for myopia was -2.30±3.23 DS (range: -0.50 to -25DS). Binary logistic regression analysis showed that myopic eyes had a higher odd of AC (OR, 0.53; 95% CI, 0.50-0.57), POAG (OR, 6.0; 95% CI, 5.26-6.82), DR (OR, 10.70; 95% CI, 3.91-29.27) and cataracts (OR, 20; 95% CI, 15.32-26.20) but not dry eye (OR, 0.74, 95% CI, 0.68-0.81), macular degeneration and pterygium (OR, 0.36; 95% CI, 0.32-0.40).

CONCLUSION

Africans with myopia are more at risk of developing allergic conjunctivitis, cataracts, POAG, and DR but not for dry eye, macular degeneration, and pterygium.

Sex differences in the relationship between axial length and dry eye in elderly patients

Purpose

The aim of this study was to explore the association between myopia and dry eye (DE)-related ocular parameters.

Methods

We recruited a total of 460 patients (mean age, 73.6 years; 40.2% men) and performed DE-related, axial length (AL) and retinal examinations. Statistical analysis revealed a significant sex difference in AL, strip meniscometry value, corneal staining score, corneal endothelial cell density, ganglion cell complex (GCC) thickness, and full macular thickness. AL was strongly age- and sex-dependent, so subsequent analyses were stratified by sex.

Results

Among DE-related parameters, strip meniscometry value (ß = -0.167, p = 0.033) and corneal endothelial cell density (ß = -0.139, p = 0.023) were correlated with AL in women but not in men. Regarding retinal parameters, GCC thickness and full macular thickness were correlated with AL in women but not in men.

Conclusion

The current results suggest a relationship between tear production and AL in elderly women and support the hypothesis that there may be a common upstream factor including the parasympathetic nervous system in the association between tear production and AL or DE and myopia.

Honey-Related Treatment Strategies in Dry Eye Disease

This systematic review and meta-analysis investigated whether honey-related treatment strategies improve the signs and symptoms of patients with dry eye disease (DED). In March 2023, the following databases were accessed for clinical trials investigating the efficacy of honey-related treatment strategies in DED: PubMed, Web of Science, Google Scholar, and EMBASE. The following data were extracted at baseline and at the last follow-up: Ocular Surface Disease Index, tear breakup time, Schirmer I test, and corneal staining. Data from 323 patients were retrieved (53.3% female, mean age 40.6 ± 18.1 years). The mean follow-up was 7.0 ± 4.2 weeks. All the endpoints of interest significantly improved from baseline to the last follow-up: tear breakup time (p = 0.01), Ocular Surface Disease Index (p < 0.0001), Schirmer I test (p = 0.0001), and corneal staining (p < 0.0001). No difference was found in tear breakup time (p = 0.3), Ocular Surface Disease Index (p = 0.4), Schirmer I test (p = 0.3), and corneal staining (p = 0.3) between the honey-related treatment strategies and the control groups. According to our main results, honey-related treatment strategies are effective and feasible to improve symptoms and signs of DED.

Development of a novel protocol to evaluate contact-lens related ocular surface health on marmosets (Callithrix jacchus)

Contact lens wear affects the ocular surface and can cause contact lens-induced dry eye (CLIDE). The purpose of this study was bifold: (1) to develop a novel protocol to assess the ocular surface in a non-human primate (NHP) model, the common marmoset (Callithrix jacchus), and (2) to characterize central corneal thickness (CCT), tear osmolarity, blink rate and tear meniscus height (TMH) longitudinally, in untreated marmosets (controls) compared to animals treated with contact lenses (CL). Longitudinal changes in CCT (N = 10 control; N = 10 treated with contact lenses, CL-treated), osmolarity (N = 4 control; N = 6 CL-treated), blink rate (N = 8 control; N = 10 CL-treated) and TMH (N = 8 control; N = 6 CL-treated) were assessed using high frequency A-scan ultrasound, the I-PEN Vet Tear Osmolarity System, a video recording system (745 frames/minute) and Image J respectively, from 70 days to 224 days (5 months) at approx. 9am, and again after 9hrs of CL wear (methafilcon A, 55% water content; Capricornia, Australia) after every 4 weeks of contact lens wear for a total of 22 weeks of treatment. Repeated measures ANOVA was used to compare eyes over time and student t-test was used to compare treated to control eyes at each time point. At baseline, untreated marmosets had a CCT (mean ± SD) of 0.31 ± 0.01 mm, tear osmolarity (mean ± SD) 311.67 ± 11.48 mOsms/L, blink rate (mean ± SD) 1.83 ± 1.79 blinks per minute (bpm) and TMH (mean ± SD) 0.07 ± 0.02 arbitrary units (au), all of which remained stable over 5 months, except blink rate that increased to 5.32 ± 1.58 bpm (p < 0.01) after 5 months. In CL-treated marmosets, however, CCT progressively increased with CL wear (baseline: 0.30 ± 0.01 mm; 5 months: 0.31 ± 0.02 mm, p < 0.05), while osmolarity decreased after 2 and 3 months of CL wear (baseline: 316.11 ± 13.63; 2 months: 302.63 ± 11.27, p < 0.05; 3 months: 302.92 ± 14.58, p < 0.05). The decrease in osmolarity occurred in parallel to an increase in blink rate (baseline: 0.98 ± 1.18 bpm; 2 months: 3.46 ± 3.04 bpm, p < 0.05; 3 months: 3.73 ± 1.50 bpm, p < 0.001). TMH decreased during the third month of CL wear (baseline: 0.06 ± 0.00 au; 3 months: 0.05 ± 0.01 au, p < 0.05), and increased after 4 months (0.08 ± 0.01 au, p < 0.05). As TMH decreased, tear osmolarity increased in both control (R = -0.66, p < 0.05) and CL-treated marmosets (R = -0.64, p < 0.05). The results suggest that marmosets treated with CL for 5 months experienced an increase in blink rate, CCT and TMH, along with a decrease in osmolarity within the first few months of CL treatment that differed from the unaffected stable ocular surface findings observed untreated animals. We hypothesize that CL wear in marmosets might induce mild corneal edema, an increased blink rate and TMH, in turn delaying the development of hyperosmolarity. These findings confirm that the marmoset is a good novel animal model for ocular surface research for the assessment of novel contact lens materials aimed to alleviate CLIDE.

Comparison of Conjunctival Sac Microbiome between Low and High Myopic Eyes

Microbial communities played a vital role in maintaining homeostasis of ocular surface. However, no studies explored the myopia-associated conjunctiva microbiota changes until now. In this study, conjunctival sac swab specimens were collected from 12 eyes of low myopia (LM), and 14 eyes of high myopia (HM) patients. The V3-V4 region of the 16S rRNA gene was amplified and then sequenced. Statistical analysis was performed to investigate differences in the taxonomy and diversity between two groups. Compared to LM, higher Ocular Surface Disease Index (OSDI) scores were observed in HM group. The Shannon index of the HM was lower than that of the LM group (P = 0.017). Principle coordinate analysis and Partial Least Squares Discrimination Analysis showed distinct microbiome composition between two groups. At the phylum level, there were higher relative abundances of Proteobacteria (68.27% vs 38.51%) and lower abundances of Actinobacteria (3.71% vs 9.19%) in HM, compared to LM group (P = 0.031, 0.010, respectively). At the genus level, the abundances of Acinetobacter in HM (18.16%) were significantly higher than the LM (6.52%) group (P = 0.011). Actinobacteria levels were negatively correlated with the myopic spherical equivalent and OSDI scores. Moreover, positive correlations were found between Proteobacteria levels and OSDI scores, Acinetobacter levels were positively correlated with myopic spherical equivalent and OSDI scores. In conclusion, HM Patients have bacterial microbiota imbalance in the conjunctival sac, compared with LM patients. Proteobacteria, Actinobacteria, Acinetobacter may play roles in the HM associated ocular surface irritation.

Myopia Is Suppressed by Digested Lactoferrin or Holo-Lactoferrin Administration

Myopia is becoming a leading cause of vision impairment. An effective intervention is needed. Lactoferrin (LF) is a protein that has been reported to inhibit myopia progression when taken orally. This study looked at the effects of different forms of LF, such as native LF and digested LF, on myopia in mice. Mice were given different forms of LF from 3 weeks of age, and myopia was induced with minus lenses from 4 weeks of age. Results showed that mice given digested LF or holo-LF had a less elongated axial length and thinned choroid, compared to those given native-LF. Gene expression analysis also showed that the groups given native-LF and its derivatives had lower levels of certain cytokines and growth factors associated with myopia. These results suggest that myopia can be more effectively suppressed by digested LF or holo-LF than native-LF.

miR-328-3p Affects Axial Length Via Multiple Routes and Anti-miR-328-3p Possesses a Potential to Control Myopia Progression

Purpose

We previously reported miR-328-3p as a novel risk factor for myopia through a genetic association study of the PAX6 gene. In the present study, we first explored the effects of miR-328-3p on other myopia-related genes, and then tested whether anti-miR-328-3p may be used for myopia control.

Methods

The luciferase report assay and transient transfection were used to confirm miR-328-3p target genes. The chromatin immunoprecipitation (ChIP) assay was used to investigate retinoic acid receptor on the miR-328-3p promoter. Mice and pigmented rabbits were induced to have myopia by the form deprivation method, and then anti-miR-328-3p oligonucleotide was topically instilled to the myopic eyes. The axial length was measured to assess the therapeutic effect of anti-miR-328-3p. A toxicity study using much higher doses was conducted to assess the safety and ocular irritation of anti-miR-328-3p.

Results

The report assay and transfection of miR-328-3p mimic confirmed that miR-328-3p dose-dependently decreased both mRNA and protein expression of fibromodulin (FMOD) and collagen1A1 (COL1A1). We subsequently showed that FMOD promoted TGF-β1 expression, and overexpression of FMOD increased the phosphorylation levels of p38-MAPK and JNK. The ChIP study showed that retinoic acid binds to miR-328-3p promoter and up-regulates miR-328-3p expression. In myopic animal studies, anti-miR-328-3p was as effective as 1% atropine and had a dose-dependent effect on suppressing axial elongation. In the toxicity study, anti-miR-328-3p did not cause any unwanted effects in the eyes or other organs.

Conclusions

Micro (mi)R-328-3p affects myopia development via multiple routes. anti-miR-328-3p possesses a potential as a novel therapy for myopia control.