Severe symptoms of short tear break-up time dry eye are associated with accommodative microfluctuations

Presbyopia, Dry Eye, and Retinal Thickness in the Middle-Aged Population: Focusing on Sex Differences

Purpose

Risk factors for presbyopia have not been fully determined although previous studies suggested presbyopia was associate with age, dry eye, and retinal ganglion cell complex thickness (GCC). We accessed these signs and common ocular symptoms in the middle-aged population focusing on sex differences when women have drastic hormonal change.

Methods

This cohort study consecutively enrolled 2743 patients aged 36-45 years (n=1000), 46-55 years (n=1000), and 56-65 years (n=743). All underwent ocular surface tests and had near add power and GCC measured. Common ocular symptoms were asked using questionnaire.

Results

Among female participants, visual symptoms (eye strain and photophobia) were more prevalent in the age group 46-55, whereas non-visual symptoms (dryness, irritation, and pain) were not. We identified symptomatic presbyopia (near add power ≥ 1.5D) in 14.4%, 73.8%, and 97.8%, positive corneal staining in 29.1%, 23.8%, and 23.9%, and a mean GCC of 98.2 μm, 105.3 μm, and 89.6 μm in the age groups 36-45, 46-55, and 56-65, respectively. Mean tear break-up time were 3.3, 3.5, and 3.3 seconds, respectively. Results indicated a large progression of presbyopia (P<0.01) from the period of 36-45 years onward and significantly increased GCC (P<0.01) in women of age group 46-55. No notable tendency was observed in symptoms and GCC for male participants.

Conclusion

Visual symptoms in women were worse between 46 and 55 years than before or after these ages. The increase of symptomatic presbyopia and GCC may be contributing to visual symptoms in addition to menopausal transition symptoms in this age group.

The influence of large-diameter multifocal contact lens on ocular surface, visual quality, and visual function for presbyopic adults with dry eye syndromes

This study investigated the influence of large-diameter multifocal contact lenses on the ocular surface, visual quality, and visual function for presbyopic adults with dry eye syndromes. The study enrolled 40-55-year-old adults with presbyopia and dry eye syndromes (DES). The subjects were randomly assigned to three groups wearing different designs of contact lenses (Proclear, SMR, and Optimum) for 6-8 h a day for two weeks. Ocular surface health, tear quality, visual quality, and visual function were measured before and after lens wear. No significant difference was observed across all three groups for the amount of conjunctival redness, blink frequency (lens on), and stereopsis vision before and after wearing. Although there seemed to be a significant declining trend for corneal staining and limbal redness, non-invasive tear break-up time (TBUT), and lipid layer thickness while lens wear, the measured values were all within the normal range. Vice-versa after lens removal, results also showed significant improvement on lipid layer thickness, blink frequency (lens off), and contact TBUT. A significant improvement was observed in the modulation transfer function (MTF) of the total area ratio after wearing contact lenses. In contrast, the MTF of the high-order aberration area ratio resulting from lens wear was lower than that of the baseline measurement. There are also significant improvements observed for SMR and Optimum regarding near visual acuity, near point of accommodation, and the subjective questionnaire (OSDI and VBP) scores. Although it is difficult to avoid a specific negative impact on the ocular surface and tear film, visual function and visual quality can still be positively improved, especially shown on larger diameter and distance-center designed multifocal contact lenses.

Particulate Matter Exposure Aggravates IL-17-Induced Eye and Nose Inflammation in an OVA/Poly(I:C) Mouse Model

PURPOSE

Data on the effects of direct particulate matter (PM) exposure on the eyes and the nose are limited. Here, an interleukin (IL)-17/neutrophil-dominant ovalbumin (OVA)/polyinosinic-polycytidylic acid (Poly(I:C)) mouse model was used to evaluate the effect of different-sized titanium dioxide (TiO₂) particles on the eyes and the nose. We also examined whether IL-17-neutralizing antibody (IL-17Ab) treatment could reverse TiO₂ effects.

METHODS

The nasal cavities and conjunctival sacs of each mouse were challenged with OVA and Poly(I:C) to induce neutrophil-dominant inflammation and then exposed to micro- and nano-TiO₂. Subsequently, IL-17Ab was administered to investigate the role of IL-17 and inflammatory parameters.

RESULTS

Micro- and nano-TiO₂ resulted in significant decreases in tear-break-up time and increases in corneal damage. Airborne micro-TiO₂ also increased nasal rubbing and sneezing counts compared with the OVA/Poly(I:C). Micro-TiO₂ exposure increased infiltration of neutrophils and IL-17A+ cells in the conjunctival tissues and the nasal mucosae. In addition, these increased symptoms and inflammation in the eyes and the nose by micro-TiO₂ exposure were inhibited by the IL-17Ab, suggesting IL-17 dependency.

CONCLUSIONS

TiO₂ aggravated IL-17-induced eye and nose inflammation and the IL-17Ab alleviated inflammation in the OVA/Poly(I:C) mouse model. These results may help develop a therapeutic modality for PM exposure and provide evidence for PM-associated diseases.

Formulation and development of tacrolimus-gellan gum nanoformulation for treatment of dry eye disease

The present study aimed at the development and evaluation of tacrolimus gellan gum nanoparticles (TGNPs) for the effective management of dry eye disease (DED) following topical application. TGNPs were developed by ionotropic gelation between gellan gum and aluminum chloride. Developed TGNPs were nanosized (274.46 ± 8.90 nm) with high % encapsulation efficiency (74.2 ± 2.4%) and loading capacity (36.14 ± 1.7%). The nanosize and spherical morphology of TGNPs was confirmed by transmission electron microscopy (TEM) and atomic force microscopy (AFM). Fourier transform infrared spectroscopy (FTIR) revealed no interaction between drug and GG. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) confirms the conversion of crystalline tacrolimus to amorphous post encapsulation in the nanoparticle. TGNPs showed prolonged drug release throughout 12 h and higher pre-corneal retention compared to tacrolimus solution. HET-CAM studies, histopathological evaluation, and Draize test confirmed the safety of the formulation for ocular use. Further, the pharmacodynamic studies using experimental DED in rabbits showed that TGNPs are effective in treating symptoms of DED. In conclusion, topical delivery of TGNPs could hold potential for efficient management of DED.

Short tear film breakup time-type of dry eye in India

Purpose

The aim of this study was to describe the clinical characteristics and risk factors of short tear film break-up time (TBUT) type of dry eye disease and compare it with other types of dry eye diseases.

Methods

This cross-sectional study included 570 patients (≥ 20 years) from the outpatient department using systematic random sampling.

Results

The age-adjusted prevalence of short TBUT type of dry eye disease was 5.4% (95% confidence interval: 3.2-6.8%). There was no difference (P > 0.05) between the total and subscale scores of the Ocular Surface Disease Index^® questionnaire between patients with short TBUT and those with aqueous tear deficiency. Both these groups differed significantly (P < 0.05) in the findings of TBUT, Schirmer I test, and Lissamine green staining score. The common symptoms in patients with short TBUT type of dry eye disease were eye fatigue (25.4%), heaviness in the eye (19.7%), and an uncomfortable sensation (14.1%). The symptoms in the aqueous tear deficiency group were light sensitivity (28.2%), dryness (19.2%), burning (13.0%), foreign body sensation (12.8%), and blurring of vision (14.1%). The risk factors associated with short TBUT type of dry eye disease were the presence of meibomian gland dysfunction (odds ratio: 3.759 [95% confidence interval: 2.135-6.618], P < 0.0001) and female sex [odds ratio: 1.954 (95% confidence interval: 1.042-3.667), P = 0.037].

Conclusion

Patients with short TBUT type of dry eye disease have symptom severity similar to aqueous tear-deficient dry eyes, but the pattern is different. The finding of this type of dry eye disease in India indicates its global presence, and ophthalmologists should consider it in their differential diagnoses.

Defining Dry Eye from a Clinical Perspective

Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint.

Changes in accommodative micro-fluctuations after wearing contact lenses of different optical designs

PURPOSE

Accommodative micro-fluctuations (AMF) are small dioptric changes during accommodation. The aim of this study was to evaluate and compare changes in AMF when wearing silicone hydrogel contact lenses of two different optical designs.

METHODS

A multi-centre, randomised, cross-over, non-dispensing study was conducted on 68 adapted contact lens wearers aged 25-35 years to compare AMF responses to a spherical and aspheric silicone hydrogel (comfilcon A) lens designs. A Righton Speedy "i" series Auto Refractometer in accommodation analyser mode was utilized before and after reading a standard text in font size 8 on an iPhone 5 for 20 min at a 25 cm viewing distance. Phone screen brightness was set by automatic adjustment mode and ambient illumination was controlled at all sites.

RESULTS

Mean ± SD AMF change from before to after the reading task was 2.25 ± 5.6 and 0.13 ± 5.7 (relative values) for the spherical and aspheric lens designs, respectively. The difference was statistically significant (P = 0.017, Paired t-test).

CONCLUSIONS

The smaller change in AMF when using an aspheric lens design suggests reduced ciliary muscle stress when reading print on a smart phone at a close distance for short periods (20 min). Contact lens wearers who frequently use digital devices and are experiencing eye strain may benefit from switching from a spherical design to one that incorporates aspheric optics.

Advances in the diagnosis and treatment of dry eye

The core mechanism of dry eye is the tear film instability. Tear film-oriented diagnosis (TFOD) is a concept to clarify the cause of tear film instability by tear film, and tear film-oriented treatment (TFOT) is a concept to treat dry eye disease by replacing the lacking components of the tear film layer based on the TFOD. In TFOD, the fluorescein breakup pattern of the tear film is important, and the subtype of dry eye can be judged to some extent from the breakup patterns. Current noninvasive devices related to the dynamic analysis of the tear film and visual acuity enabled the diagnosis of dry eye, subtype analysis, and the extent of severity. In Asian countries, secretagogues represent the main treatment in TFOT. Since meibomian gland dysfunction is a factor that greatly affects the tear breakup time, its treatment is also essential in the dry eye treatment strategy. A newly discovered dry eye subtype is the short breakup time-type (BUT) of dry eye. The only abnormal finding in this disease is the short BUT, suggesting a relationship with ocular neuropathic pain and eye strain. Recently, data from many studies have accumulated which show that dry eye is a life-style disease. In addition to the treatment of dry eyes, it is becoming possible to prevent the onset by intervening with the daily habits, diet, exercise and sleep, etc. It has been pointed out that oxidative stress is also involved in the pathology of dry eye, and intervention is being carried out by improving diet and taking supplements. Future research will be needed to link clinical findings to the molecular biological findings in the tear film.

Kinetic visual acuity is correlated with functional visual acuity at higher speeds

Objective

To measure the kinetic visual acuity (KVA) which is the ability to identify approaching objects and the functional visual acuity (FVA) which is continuous VA during 1 min under binocular and monocular condition (non-dominant eye shielding) for healthy subjects, and related ocular parameters to explore their correlation and implication in aspect of integrated visual function.

Methods

The mean age of the 28 participants was 38.6±8.9 years (range, 23–57 years; 6 women). A KVA metre (AS-4Fα) and FVA metre (AS-28) were used to measure KVA and FVA, respectively. Multiple regression analysis was conducted to explore correlations among the measured visual function and related parameters, including age, binocularity, best-corrected visual acuity, refraction and tear break-up time.

Results

The results of binocular KVA were better than monocular KVA at all speeds. A strong correlation was found between monocular and binocular KVA. The results of binocular FVA were better than monocular FVA (p<0.001) and there was a correlation between monocular and binocular FVA (R=0.638, p<0.001), as well as the maintenance rate for FVA (R=0.228, p=0.003). A linear mixed-effects model revealed that binocularity for KVA prediction was significant at all speeds and FVA was also significant at 60 km/h (p<0.05).

Conclusion

The current results suggest that both binocularity and FVA may contribute to KVA.

Trial registration number

UMIN00032385

Population-based study on the epidemiology of dry eye disease and its association with presbyopia and other risk factors

BACKGROUND

To investigate the incidence and prevalence of dry eye disease (DED) in Taiwan and to explore its potential risk factors.

METHODS

Population-based longitudinal data from 2000 to  2013 based on Taiwan National Health Insurance Research Database were used in this study. To explore potential risks factor of interest, patients who had DED diagnosis before the exposure were excluded. Each patient from the exposure and his/her matched non-exposure controls were followed until either the diagnosis of DED or censorship. Kaplan-Meier method was used to compare the hazard of DED between cohorts. Stratified Cox proportional hazard models were applied to estimate the adjusted effect.

RESULTS

The age-adjusted prevalence for men and women were 6.81% and 16.16%, respectively. The age-gender rate of the same period was 549 per 10⁵ person-years. The propensity-adjusted hazard ratio of DED is 1.816 for the presbyopia versus non-presbyopia (with 95% CI = [1.737, 1.897] with p value < 0.0001).

CONCLUSIONS

The DED incidence for women peaked at age 50-74, while that for men peaked at age ≧ 75. The incidence in young people seems stable both for women and for men. While exploring the factors of DED, there is a significant association between presbyopia and DED even after matching age/gender and comorbidity conditions. Further clinical studies are needed to justify whether the corrective refractive treatment such as presbyopic glasses to treat the frequently hyperopic status of these patients could be beneficial to both dry eye and presbyopic condition.

Quantification of accommodative response and visual performance in non-presbyopes wearing low-add contact lenses

PURPOSE

Digital eye strain encompasses a range of ocular and visual symptoms across all age groups. Recently, symptoms associated with accommodative or binocular vision stress have become a major problem, especially in young individuals. The purpose of this prospective, single-blinded study was to objectively quantify the accommodative response and visual performance of low-add soft contact lenses (CLs) in young non-presbyopic individuals.

METHODS

A daily disposable low-add bifocal design lens (low-add CL) was tested. It employs a centre-distance optical zone and peripheral zone with the added power of +0.50 D to support near vision. Sixteen subjects aged 20-39 years were enrolled in the study. Refractive state and accommodation were measured using an open-field autorefractor with three target vergences, namely, -0.20 D, -2.5 D, and -4.0 D. Binocular visual acuity at high (100%) and low (40%, 20%) contrast and reading ability were assessed. Monofocal soft CLs were used as controls.

RESULTS

Accommodative response with low-add CLs was significantly smaller than those with two monofocal CL wearing conditions, i.e., at 40 cm (2.5 D of stimulus) and 25 cm (4.0 D of stimulus) (all p < 0.05). The 20% contrast visual acuity at distance was significantly better with low-add CLs and second-time monofocal CLs compared to first-time monofocal CLs (all p < 0.05). The reading ability was not significantly different.

CONCLUSIONS

Quantification of accommodative response and visual performance demonstrated that using low-add CLs alleviated the accommodation under the near-vision condition, without sacrificing distance vision, in non-presbyopes.

Short Tear Film Breakup Time-Type Dry Eye

Measurement of tear film breakup time (TBUT) has become a standard diagnostic procedure in the dry eye clinic. Short TBUT-type dry eye is characterized by TBUT of less than 5 seconds and dry eye symptoms such as ocular fatigue or dryness; the importance of this type has recently been gaining prominence. Patients with this condition show no reduction in tear production and no staining of the ocular surface. The severity of symptoms is almost the same as in dry eye in which the ocular surface is stained with rose bengal or fluorescein. In addition to discomfort, patients suffer from decreased vision due to the unstable tear film, which can be attributed to the relative abnormality of the lipid layer, aqueous layer, and/or mucin layer. The diagnosis should be performed carefully on the basis of the patient's symptoms and the TBUT test, because the ocular surface appears normal and remains unstained.

Relation of accommodative microfluctuation with dry eye symptoms in short tear break-up time dry eye

Purpose

To investigate accommodative microfluctuations (AMFs) and visual function in short tear break-up time (BUT)-type dry eye (DE) and non-DE subjects.

Methods

This prospective comparative study included 48 volunteers with DE symptoms (mean age 34.8 ± 5.5 years, age range 25–42 years) and 73 without DE symptoms (mean age 30.6 ± 4.7 years, age range 25–42 years). The eyes were divided into two groups: (1) DE group with DE symptoms and BUT ≤ 5 s and (2) non-DE group without DE symptoms and BUT > 5 s. We excluded eyes with Schirmer score ≤ 5 mm and positive keratoconjunctival epithelial damage. Tear evaluation, AMF, and functional visual acuity (VA) examinations were performed. AMF parameters included total high-frequency component (HFC), HFC with low accommodation for the task of staring into the distance (HFC1), and HFC with high accommodation for deskwork (HFC2). Functional VA parameters included starting VA, functional VA, visual maintenance ratio, and blink frequency.

Results

A total of 33 and 34 eyes were categorized in the DE and non-DE groups, respectively. Mean blink frequency and HFC1 values were significantly higher in the DE group than they were in the non-DE group.

Conclusions

DEs with symptoms showed abnormal AMF and visual function, which may be associated with DE symptoms.