Prevalence of dry eye disease in the low vision population at the University of Colorado

Purpose: To evaluate the prevalence of diagnosed dry eye syndrome, meibomian gland dysfunction, and blepharitis amongst the low vision population. Methods: A retrospective analysis was conducted on patients seen in the University of Colorado Low Vision Rehabilitation Service between the dates of 12/1/2017 and 12/1/2022. 74 ICD-10 codes were used to identify patients as having dry eye syndrome or not having dry eye syndrome. Data was further analyzed to determine the prevalence of blepharitis and meibomian gland dysfunction using 29 blepharitis and 9 meibomian gland dysfunction ICD-10 codes. Data were also analyzed to determine the age and sex of the patients with diagnosed dry eye syndrome. Results: The percentage of patients with a diagnosis of dry eye syndrome by an eyecare provider was 38.02 %. The prevalence of dry eye syndrome by age group was 3.57 % for 0–19 years, 14.35 % for 20–39 years, 29.07 % for 40–59 years, 43.79 % for 60–79 years, and 46.21 % for 80 and above. The prevalence of meibomian gland dysfunction and blepharitis was 11.90 % and 9.1 % respectively. Dry eye syndrome prevalence amongst males was 31.59 % and 42.47 % for females. Conclusion: This study demonstrates that dry eye syndrome in the low vision population is a significant co-morbidity occurring in over a third of patients in the University of Colorado Low Vision Rehabilitation Service. These findings are meaningful as ocular comfort should not be overlooked while managing complex visual needs. (AU)

Thermosensitive TRP Channels Are Functionally Expressed and Influence the Lipogenesis in Human Meibomian Gland Cells.

While the involvement of thermosensitive transient receptor potential channels (TRPs) in dry eye disease (DED) has been known for years, their expression in the meibomian gland (MG) has never been investigated. This study aims to show their expression and involvement in the lipogenesis of the MG, providing a possible new drug target in the treatment of DED. Our RT-PCR, Western blot and immunofluorescence analysis showed the expression of TRPV1, TRPV3, TRPV4 and TRPM8 in the MG at the gene and the protein level. RT-PCR also showed gene expression of TRPV2 but not TRPA1. Calcium imaging and planar patch-clamping performed on an immortalized human meibomian gland epithelial cell line (hMGECs) demonstrated increasing whole-cell currents after the application of capsaicin (TRPV1) or icilin (TRPM8). Decreasing whole-cell currents could be registered after the application of AMG9810 (TRPV1) or AMTB (TRPM8). Oil red O staining on hMGECs showed an increase in lipid expression after TRPV1 activation and a decrease after TRPM8 activation. We conclude that thermo-TRPs are expressed at the gene and the protein level in MGs. Moreover, TRPV1 and TRPM8's functional expression and their contribution to their lipid expression could be demonstrated. Therefore, TRPs are potential drug targets and their clinical relevance in the therapy of meibomian gland dysfunction requires further investigation.

Red filter meibography by smartphones in patients with meibomian gland dysfunction: a validity and reliability study.

OBJECTIVE: The objective of this study is to determine the validity and reliability of the red filter meibography by smartphone compared with infrared in assessing meibomian gland drop-out. METHODS AND ANALYSIS: An analytical cross-sectional study was done with a total of 35 subjects (68 eyes) with suspected MGD based on symptoms and lid morphological abnormalities. Meibomian glands were photographed using two smartphones (Samsung S9 and iPhone XR) on a slit-lamp with added red filter. Images were assessed subjectively using meiboscore by the two raters and drop-out percentages were assessed by ImageJ. RESULTS: There was no agreement in meiboscore and a minimal level of agreement in drop-out percentages between red filter meibography and infrared. Inter-rater reliability showed no agreement between two raters. Intra-rater reliability demonstrated weak agreement in rater 1 and no agreement in rater 2. CONCLUSION: Validity of the red filter meibography technique by smartphones is not yet satisfactory in evaluating drop-out. Further improvement on qualities of images must be done and research on subjective assessment was deemed necessary due to poor results of intrarater and inter-rater reliability.

Intense pulsed light therapy for ocular surface diseases.

Intense pulsed light (IPL) is a non-laser, high-intensity light source that has been shown to play a valuable role in dermatology and has been adopted in ophthalmology for treating meibomian gland dysfunction (MGD). In this review, we discuss the mechanism of action of IPL, including its benefits in ophthalmology. IPL therapy has been shown to improve tear film stability, meibomian gland (MG) function, and subjective symptoms of ocular dryness in MGD patients. Moreover, emerging evidence suggests that IPL therapy is beneficial for other ocular surface diseases, such as blepharitis and chalazia. Hence, it can be inferred that IPL has potential as a therapeutic modality in future applications. Large clinical and experimental trials are needed to exploit the full potential of IPL as a treatment for recurrent chalazia, Sjögren's syndrome, and other causes of dry eye disease (DED). This paper reviews the published literature related to the application of IPL for treating ocular surface diseases.

Expression of ATP-Binding Cassette Transporter A1 (ABCA1) in Eyelid Tissues and Meibomian Gland Epithelial Cells.

Purpose: To validate the adenosine triphosphate (ATP)-binding cassette transporter A1 (ABCA1) expression and distribution in human eyelid tissues and meibomian gland epithelial cells. Methods: Meibomian gland tissues from human eyelids were isolated by collagenase A digestion and cultured in defined keratinocyte serum-free medium (DKSFM). Infrared imaging was used to analyze the general morphology of meibomian glands. Hematoxylin and eosin (H&E) staining and Oil Red O staining were used to observe the morphological structure and lipid secretion in the human meibomian gland tissues. Quantitative real-time polymerase chain reaction, western blotting, and immunostaining were used to detect the mRNA and protein expression and cytolocalization of ABCA1 in the meibomian gland tissues and cultured cells. Results: The degree of loss of human meibomian gland tissue was related to age. Meibomian gland lipid metabolism was also associated with age. Additionally, human meibomian gland tissues express ABCA1 mRNA and protein; glandular epithelial cells express more ABCA1 mRNA and protein than acinar cells, and their expression in acinar cells decreases with differentiation. Furthermore, the expression of ABCA1 was downregulated in abnormal meibomian gland tissues. ABCA1 was mainly localized on the cell membrane in primary human meibomian gland epithelial cells (pHMGECs), whereas it was localized in the cytoplasm of immortalized human meibomian gland epithelial cells (iHMGECs). The mRNA and protein levels of ABCA1 in pHMGECs were higher than those in iHMGECs. Conclusions: Meibomian gland tissues of the human eyelid degenerate with age. ABCA1 expression in acinar cells decreases after differentiation and plays an important role in meibomian gland metabolism.

Comparative Characterization of Human Meibomian Glands, Free Sebaceous Glands, and Hair-Associated Sebaceous Glands Based on Biomarkers, Analysis of Secretion Composition, and Gland Morphology.

Meibomian gland dysfunction (MGD) is one of the main causes of dry eye disease. To better understand the physiological functions of human meibomian glands (MGs), the present study compared MGs with free sebaceous glands (SGs) and hair-associated SGs of humans using morphological, immunohistochemical, and liquid chromatography-mass spectrometry (LCMS)-based lipidomic approaches. Eyelids with MGs, nostrils, lips, and external auditory canals with free SGs, and scalp with hair-associated SGs of body donors were probed with antibodies against cytokeratins (CK) 1, 8, 10, and 14, stem cell markers keratin 15 and N-cadherin, cell-cell contact markers desmoglein 1 (Dsg1), desmocollin 3 (Dsc3), desmoplakin (Dp), plakoglobin (Pg), and E-cadherin, and the tight junction protein claudin 5. In addition, Oil Red O staining (ORO) was performed in cryosections. Secretions of MGs as well as of SGs of nostrils, external auditory canals, and scalps were collected from healthy volunteers, analyzed by LCMS, and the data were processed using various multivariate statistical analysis approaches. Serial sections of MGs, free SGs, and hair-associated SGs were 3D reconstructed and compared. CK1 was expressed differently in hair-associated SGs than in MGs and other free SGs. The expression levels of CK8, CK10, and CK14 in MGs were different from those in hair-associated SGs and other free SGs. KRT15 was expressed differently in hair-associated SGs, whereas N-cadherin was expressed equally in all types of glands. The cell-cell contact markers Dsg1, Dp, Dsc3, Pg, and E-cadherin revealed no differences. ORO staining showed that lipids in MGs were more highly dispersed and had larger lipid droplets than lipids in other free SGs. Hair-associated SGs had a smaller number of lipid droplets. LCMS revealed that the lipid composition of meibum was distinctively different from that of the sebum of the nostrils, external auditory canals, and scalp. The 3D reconstructions of the different glands revealed different morphologies of the SGs compared with MGs which are by far the largest type of glands. In humans, MGs differ in their morphology and secretory composition and show major differences from free and hair-associated SGs. The composition of meibum differs significantly from that of sebum from free SGs and from hair-associated SGs. Therefore, the MG can be considered as a highly specialized type of holocrine gland that exhibits all the histological characteristics of SGs, but is significantly different from them in terms of morphology and lipid composition.

Evaluation of visual field and ocular surface parameters by clinical comparison after blepharoplasty for dermatochalasis.

PURPOSE: To evaluate the effect of upper eyelid blepharoplasty surgery on corneal topography, visual field, ocular surface, meibography, corneal biomechanics and dry eye parameters. METHODS: This prospective study included a total 80 eyes of 40 patients. Following a detailed ophthalmological examination, standardized patient satisfaction questions were posed to patients before and after upper eyelid blepharoplasty surgery. Visual field test, non-invasive break up time (NIBUT), meibography, and corneal topography parameters were analyzed and evaluated. RESULTS: The mean (+) visible areas in the visual field were found to be 46.20±24.96 preoperatively, 56.73±21.98 at the 1st postoperative month and 65.96±18.5 at the 3rd month, which were statistically significant. NIBUT values preoperatively, at 1 month and at 3 months were 11.26±4.48, 11.16±4.5 and 10.14±4.0, respectively, which were statistically significant. Meibomian gland loss rates on meibography preoperatively and postoperatively at 1 and 3 months were found to be 30.24±8.3, 29.36±8.2 and 28.22±7.7 respectively and were statistically significant. With the scoring system after blepharoplasty, patients reported improvement in their symptoms. CONCLUSION: Upper eyelid blepharoplasty surgery is predicted to increase the quality of vision. It was observed that there was a functional and cosmetic improvement in the complaints of the patients after blepharoplasty. However, blepharoplasty may cause changes in eyelid dynamics and cause dry eye syndrome.

Oleic acid induces lipogenesis and NLRP3 inflammasome activation in organotypic mouse meibomian gland and human meibomian gland epithelial cells.

The accumulation of oleic acid (OA) in the meibum from patients with meibomian gland dysfunction (MGD) suggests that it may contribute to meibomian gland (MG) functional disorder, as it is a potent stimulator of acne-related lipogenesis and inflammation in sebaceous gland. Therefore, we investigate whether OA induces lipogenesis and inflammasome activation in organotypic cultured mouse MG and human meibomian gland epithelial cells (HMGECs). Organotypic cultured mouse MG and HMGECs were exposed to OA or combinations with specific AMPK agonists 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR). Lipogenic status, ductal keratinization, squamous metaplasia, NLRP3/ASC/Caspase-1 inflammasome activation, proinflammatory cytokine IL-1ß production, and AMPK pathway phosphorylation in MG were subsequently examined by lipid staining, immunofluorescence staining, immunohistochemical staining, ELISA assay, and Western blot analyses. We found that OA significantly induced lipid accumulation, ductal keratinization, and squamous metaplasia in organotypic cultured MG, as evidenced by increased lipids deposition within acini and duct, upregulated expression of lipogenic proteins (SREBP-1 and HMGCR), and elevation of K10/Sprr1b. Additionally, OA induced NLRP3/ASC/Caspase-1 inflammasome activation, cleavage of Caspase-1, and production of downstream proinflammatory cytokine IL-1ß. The findings of lipogenesis and NLRP3-related proinflammatory response in OA-stimulated HMGECs were consistent with those in organotypic cultured MG. OA exposure downregulated phospho-AMPK in two models, while AICAR treatment alleviated lipogenesis by improving AMPK/ACC phosphorylation and SREBP-1/HMGCR expression. Furthermore, AMPK amelioration inhibited activation of the NLRP3/ASC/Caspase-1 axis and secretion of IL-1ß, thereby relieving the OA-induced proinflammatory response. These results demonstrated that OA induced lipogenic disorder and NLRP3 inflammasome activation in organotypic cultured mouse MG and HMGECs by suppressing the AMPK signaling pathway, indicating OA may play an etiological role in MGD.

Ocular surface and meibomian gland evaluation in euthyroid Graves' ophthalmopathy.

PURPOSE: Euthyroid Graves' ophthalmology (EGO) refers to the subgroup of thyroid eye disease patients with distinct clinical presentations. This study evaluated the ocular surface and meibomian gland changes in EGO patients. METHODS: A cross-sectional study was conducted at The Chinese University of Hong Kong including 34 EGO patients and 34 age-and sex- matched healthy controls. Outcome measures include anterior segment examination, keratographic and meibographic imaging. RESULTS: Between 34 EGO patients and 34 age and sex-matched healthy controls, EGO was associated with a higher ocular surface disease index (P < 0.01), higher severity of meibomian gland dropout (upper: P < 0.001, lower: P < 0.00001) and higher percentage of partial blinking (P = 0.0036). The worse affected eyes of the EGO patients were associated with corneal staining (P = 0.0019), eyelid telangiectasia (P = 0.0009), eyelid thickening (P = 0.0013), eyelid irregularity (P = 0.0054), meibomian gland plugging (P < 0.00001), expressibility (P < 0.00001), and meibum quality (P < 0.00001). When the two eyes of the same EGO patient were compared, the degree of meibomian gland dropout was higher among the worse affected eyes (upper: P < 0.00001, and lower: P < 0.00001). Tear meniscus height, lipid layer thickness, and noninvasive break-up time were comparable between the two eyes of EGO patients and also between EGO patients and healthy controls. TMH was positively correlated with the degree of exophthalmos (r = 0.383, P < 0.05). CONCLUSION: EGO patients have more ocular surface complications and meibomian gland dropouts than healthy controls. Almost 60% of them had dry eye symptoms, but aqueous deficiency was not apparent. Further studies are warranted to clarify the mechanism of dry eye in EGO. (249 words).

Morphological and functional characteristics of the meibomian gland in pediatric patients with epiblepharon.

BACKGROUND: To observe morphologic and functional changes in meibomian glands in pediatric patients with and without lower eyelid epiblepharon. METHODS: In this prospective observation study, 55 eyes of 55 patients( 24 males, 31 females; mean age ± SD,9.82 ± 2.59 years; range 6-14 years) and 60 eyes of 60 controls ( 32 males, 28 females; mean age ± SD,10.57 ± 2.75 years; range 6-14 years) were included. The following tests were performed: eyelid margin abnormality by slit-lamp examination, measurement of noninvasive keratographic break-up time (NIKBUT), grading of absence of meibomian gland (meibography score) assessed with noncontact meibography, morphologic changes of meibomian glands (thinning, dilatation and distortion), tear production by the Schirmer 1 test, and grading of meibum quality and meibomian gland expressibility. RESULTS: The morphologic changes in meibomian glands were more common in the epiblepharon group (56.36%) than in the control group (28.33%) (p = 0.002). The meibum quality was worse in the epiblepharon group than in the control group (p = 0.009), and the NIKBUT was significantly shorter in the epiblepharon group than in the control group (p = 0.012). There was no significant difference in the Schirmer 1 test, meibomian gland expressibility, eyelid margin abnormality score or total meibography score between the two groups. Morphologic changes in the meibomian glands in the upper eyelids (38.18%) were more common than those in the lower eyelids (20%) (p = 0.036) in the epiblepharon group, and the meibography score was higher in the upper eyelids than in the lower eyelids (p = 0.001). CONCLUSION: There are morphological and functional changes in meibomian glands in pediatric patients with lower eyelid epiblepharon. Although the inverted eyelashes were located in the lower eyelid, morphological changes in the meibomian glands were more common in the upper eyelid.

2023 Prentice Medal Award lecture: Ocular surface-related symptoms of discomfort and other stories.

ABSTRACT: I have been fortunate to spend portions of my career in each of private practice, industry, and academia. At some times, these occupations have dictated the research direction, whereas, at others, curiosity has been allowed to dominate. This has resulted in multiple avenues of inquiry (some might say, too many), along which I have traveled with a rich and varied cast of collaborators, who have all taught me a great deal. The privilege of being awarded the Charles F. Prentice medal provides me an opportunity to summarize some of these activities. Beginning with an attempt to use contact lenses to solve a problem for those affected by albinism, the story shifts to addressing some of the wider deficiencies of contact lenses, in particular the consequences of their oxygen permeability and tendency to induce discomfort toward the end of the day. After briefly considering some aspects of meibomian gland function, the narrative concludes with the latest investigations of neurological links between the cornea and migraine.

Comparison of non-pharmaceutical treatments for evaporative dry eye: a randomised controlled study protocol.

INTRODUCTION: The lipid layer of the tear film is critical to maintaining the integrity of the tear film and absence in the tear film lipid layer (TFLL) is one of the main causes of evaporative dry eye (EDE) in dry eye disease patients, resulting in excessive evaporation (so-called hyperevaporative dry eye). This study protocol will be designed to assess and compare the effects of intense pulsed light (IPL), heated eye mask (HEM), vectored thermal pulsation system (VTPS) and eyelid massage device (EMD) for improving signs and symptoms of EDE. METHODS AND ANALYSIS: Patients with EDE will be randomly divided into IPL, HEM, VTPS and EMD groups and will be followed up for 6 weeks. The primary outcome measure will be non-invasive tear breakup time (NITBUT). The secondary outcome measures will include, TFLL score, meibomian gland quality and expressibility change from baseline conjunctivocorneal staining with fluorescein and lissamine, tear meniscus height, conjunctival hyperaemia (redness score) and ocular surface disease index questionnaire. Additionally, adverse events will be monitored and documented. ETHICS AND DISSEMINATION: Ethics approval number: IRB(2023)K019.01. The findings will be shared regardless of the effect's direction. TRIAL REGISTRATION NUMBER: NCT05923528.

First-in-human Clinical Trial of a Novel Eyelid warming Device in Meibomian Gland Dysfunction.

BACKGROUND: Meibomian gland dysfunction (MGD) causes significant patient morbidity as well as economic burden. OBJECTIVES: To evaluate a novel eyelid warming and a neuro-stimulating device that delivers heat via low-level infrared radiation to the eyelids of patients with MGD. METHODS: In this prospective interventional study, patients with MGD were recruited at a single medical center. The main outcome measures included changes in tear break-up time (TBUT), Schirmer's test, and Ocular Surface Disease Index (OSDI), overall satisfaction, and corneal signs of dry eye. Patients were instructed to use the device twice daily for 5 minutes on each eye for a total of 14 days. Follow-up assessments were performed after the 2-week treatment. RESULTS: A total of 10 patients were included; mean age was 67 ± 16 years; six males (60%). Changes in pre- vs. post-treatment TBUT (5.0-6.11), OSDI (28.1-23.9), and Schirmer score (8.67-7.11) were not statistically significant. Over a course of 243 treatments, 131 (54%) demonstrated improvement in symptoms, 40% found no change, and 6% experienced worsening of symptoms. General satisfaction was observed overall in 80% of the patients. No adverse events were observed. CONCLUSIONS: In this first study of a novel eyelid warming device, overall subjective satisfaction was reported in 80% of patients. Potential advantages of this user-friendly device include its ability to improve MGD and tear film stability, as well as symptomatic relief, while allowing the user to continue with normal daily functioning while undergoing treatment.

Need to Increase the Number of Intense Pulsed Light (IPL) Treatment Sessions for Patients with Moderate to Severe Meibomian Gland Dysfunction (MGD) Patients.

PURPOSE: To evaluate whether patients with moderate-to-severe meibomian gland dysfunction (MGD) will benefit from increasing the number of intense pulsed light (IPL) treatment sessions. METHODS: Ninety Asian adult with MGD (stages 3-4) were enrolled in this retrospective study. In Group1, 30 patients completed the five-session IPL treatment, 63.33% of which also received meibomian gland expression (MGX). In Group 2, 60 patients received three-session IPL treatment, 60.0% of which also accepted MGX. Both intragroup and intergroup analyses were conducted. RESULTS: The population characteristics, clinical baseline characteristics and therapeutic regimen were comparable between Group1 and Group2. The symptoms and most clinical indices improved after IPL treatment finished in both two groups. No statistical difference was found in any improvement level of all symptomatic and physical indices, including the Ocular surface disease index, tear break-up time, Demodex, corneal staining, meibum quality, meibomian gland expressibility, and MGD stage (all p ≥ 0.05) between the two groups at any time, not only month by month, but also at the terminal visit. However, the response rate of Group1 after the five-session treatment (70.00%) was increased compared to that of Group2 after the three-session treatment (63.33%). CONCLUSIONS: Increasing the number of IPL sessions is beneficial for patients with moderate to severe MGD to increase the response rate of treatment, rather than the improvement level. However, there is no need for patients who respond well to a routine number of IPL treatments to undergo additional IPL sessions.

[Efficacy of 0.05% cyclosporine A combined with vitamin A palmitate in the treatment of meibomian gland dysfunction-related dry eye].

Objective: To evaluate the efficacy of 0.05% cyclosporine A eye drops combined with vitamin A palmitate eye gel in the treatment of dry eye associated with meibomian gland dysfunction (MGD). Methods: A single-center, prospective, randomized, parallel controlled trial design was used to include patients diagnosed with MGD-associated dry eye. The patients were randomly divided into three groups and administered with medications binocularly for 12 weeks. The CsA+VA group was given 0.05% cyclosporine A eye drops twice a day and vitamin A palmitate eye gel three times a day. The CsA+HA group was given 0.05% cyclosporine A eye drops twice a day and 0.1% sodium hyaluronate eye drops three times a day. The HA group was given 0.1% sodium hyaluronate eye drops 3 times a day. The OSDI score, tear meniscus height, fluorescein tear break-up time, Schirmer Ⅰ test (without anesthesia), tear film lipid layer thickness, meibomian gland morphology and function examination, and corneal fluorescein sodium staining score were evaluated at baseline, 4, 8, and 12 weeks after the initiation of the treatment, respectively. Results: A total of 120 patients with MGD-related dry eye met the enrollment criteria, but 10 patients were lost to follow-up; 110 patients were finally included for observation, including 36 patients in the CsA+VA group, 38 in the CsA+HA group and 36 in the HA group. The OSDI score, tear meniscus height, fluorescein tear break-up time and meibomian gland secretion of the 3 groups were significantly improved. At the 12th week of the treatment, the differences of the CsA+VA group [25.45±15.11, (0.30±0.13) mm, (3.72±1.40) s, (5.03±2.52) points] and the CsA+HA group [26.98±16.89, (0.27±0.10) mm, (4.34±1.76) s, (5.11±2.39) points] from the HA group [24.57±11.26, (0.24±0.06) mm, (3.18±1.11) s, (9.11±3.34) points] were statistically significant (P<0.05). Compared with the CsA+HA group [(68.39±26.66) nm], the tear film lipid layer thickness in the CsA+VA group [(72.61±23.65) nm] was significantly increased (P<0.05). In the CsA+VA group, the meibomian gland secretion characters and discharge capacity among patients with severe abnormalities [(6.28±2.59) and (5.89±2.77) points at the 12th week of treatment], moderate abnormalities [(4.27±2.02) and (4.64±2.02) points at the 12th week of treatment] and mild abnormalities [(2.80±0.84) and (2.60±0.55) points at the 12th week of treatment] were significantly different (P<0.05). Conclusion: 0.05% cyclosporine A combined with vitamin A palmitate can significantly improve the symptoms and signs of patients with MGD-related dry eye, especially the tear film lipid layer thickness and the meibomian gland secretion characters and discharge capacity in severe cases.

Sex Differences in the Prevalence of Meibomian Gland Dysfunction: A Mini Review.

PURPOSE: In this review, we aimed to investigate the literature on sex-specific prevalence of meibomian gland dysfunction (MGD) and to determine whether women or men are more at risk for MGD. METHODS: A search was conducted on PubMed using the terms: (Sex OR Gender OR prevalence) AND (Meibomian gland). RESULTS: Twenty-four relevant studies on MGD prevalence were identified, including 10 population-based and 14 hospital-based studies. Among the population-based studies, five studies reported higher rates among men, three studies found no differences, and one study observed higher rates among women. In the hospital-based studies, 10 studies reported no difference, two found higher rates among men, and one found higher among women. In the reviewed literature, there was a considerable variation between studies in terms of quality, sample size, age ranges, diagnostic criteria. CONCLUSIONS: While most of the population-based studies suggest a higher prevalence among men, the majority of clinic-based studies show no significant difference. Further research with larger samples and standardized criteria is needed to determine whether men are indeed more susceptible to MGD.

Ocular surface parameter changes in the untreated fellow eye after unilateral cataract surgery with short-term administration of anti-inflammatory eye drops.

This study aimed to investigate the changes in clinical parameters of dry eye disease and meibomian gland dysfunction in both the operated and untreated fellow eyes of patients who underwent unilateral cataract surgery with the short-term administration of anti-inflammatory eye drops in the surgical eye. The medical charts of 57 consecutive patients who underwent unilateral cataract surgery and received 1% prednisolone acetate and non-steroidal anti-inflammatory drug (NSAID, 0.1% bromfenac sodium) eye drops were reviewed. The preoperative ocular surface disease index questionnaire score (38.9 ± 20.5) decreased significantly to 15.2 ± 16.4 at post-surgical 1 week and further to 12.8 ± 11.4 after 1 month. Although meibum quality grade increased and corneal sensitivity decreased at 1 week in operated eyes, corneal erosion scores and Sjogren's International Collaborative Clinical Alliance ocular staining scores even improved over a month in the untreated fellow eyes. The tear matrix metalloproteinase (MMP)-9 grade decreased in both operated eyes and untreated fellow eyes after 1 month from surgery. In conclusion, the short-term topical anti-inflammatory treatment using steroid and NSAID eye drops in the operated eye after cataract surgery decreased subjective ocular surface discomfort and improved ocular surface staining scores and tear MMP-9 expression in the untreated fellow eyes.

Effects of climate factors and Demodex infestation on meibomian gland dysfunction-associated dry eye diseases.

We examined the effects of climatic factors and Demodex infestations on meibomian gland dysfunction (MGD)-associated dry eye disease (DED) in a cross-sectional study. This study included 123 patients from Tianjin and Chengdu regions, and climate factors and the Air Quality Index (AQI) were recorded for one year. Ocular surface parameters and Demodex infestations were evaluated using various tests. Significant differences in all climatic factors and AQI were observed between Tianjin and Chengdu (P < 0.01), and ocular surface parameters also differed significantly between the two regions (P < 0.05). Temperature, relative humidity, and precipitation positively correlated with tear break-up time (BUT), meibum gland expressibility, and lid margin irregularity but negatively correlated with lissamine green staining scores (P < 0.05). Wind speed and atmospheric pressure positively correlated with corneal fluorescein staining and lissamine green staining but negatively correlated with BUT and lid margin irregularity (P < 0.05). AQI positively correlated with DED symptoms and corneal findings but negatively correlated with tear film stability and meibomian gland characteristics (P < 0.05). Demodex infestation was only positively correlated with meibum quality scores (P < 0.05). Our findings suggest that geographic climates influence ocular surface characteristics in MGD-associated DED, with daily precipitation potentially playing a significant role, and Demodex infestation contributes to meibum gland degeneration.

Changes of dry eye parameters after small incision lenticule extraction surgery in patients with different ocular surface disease index scores.

To evaluate the changes of dry eye parameters after small incision lenticule extraction (SMILE) surgery in patients with different ocular surface disease index (OSDI) scores. Prospective research. Participants were divided into two groups: Group A, OSDI < 13; and Group B, OSDI ≥ 13. The OSDI scores, tear meniscus height (TMH), first non-invasive tear film break-up time (NIBUT-First), and meibomian gland loss (MGL, %) were recorded at postoperative 1 -week and 1-month.113 eyes (57 patients) were enrolled, 70 eyes in Group A, and 43 eyes in Group B. In Group A, the OSDI scores significantly increased at 1-week and 1-month postoperative (all P < 0.001); the TMH, NIBUT-First and lipid layer grade significantly decreased at postoperative 1-week (P = 0.003, 0.005, 0.007, 0.004, respectively), but returned to preoperative level at 1-month postoperative. In Group B, only the lipid layer grade significantly decreased at postoperative 1-week (P < 0.05). Patients with different preoperative OSDI scores may experience different changes early after SMILE surgery. Patients with OSDI scores < 13 may experience more dramatic changes in dry eye symptoms which would resolve, while subjective complains could still exists at 1 month after surgery.