Beauty versus Health-How Eyelash Extensions May Affect Dry Eye Disease?

Background: Eyelash extensions (EEs) are among the most popular cosmetic procedures today. There is no prospective study demonstrating how this procedure affects the ocular surface and eye dryness in particular. The goal of this study is to evaluate the effect of EEs removal on dry eye symptoms and signs. Materials and Methods: The subjects were prospectively recruited from routine clinical examinations for dry eye complaints. Only subjects with an OSDI score above 31 were included in the study. The subjects also planned to have the EEs removed and agreed to abstain from makeup use and new cosmetic procedures for 4 weeks. The presence of dry eye was evaluated by an OSDI questionnaire, and objectively by tear breakup time (TBUT), staining (Oxford scale) and blinking intervals. All tests for dry eye were performed at baseline and 4 weeks after EEs removal. Results: The mean age of our patients, all female, was 28 years. The size and type of EEs was diverse. The decision process was mainly based on appearance and models. None of the subjects had any health conditions. The mean result from the score from the OSDI questionnaire at the baseline was 33.4 and improved to 26.7 points 4 weeks after EEs removal. Objectively, the mean TBUT increased from 11.25 to 13.96 s. For the same period, the blinks increased by two per minute, and the staining was reduced by 1.0 grade. Conclusions: Removal of EEs improves the symptoms and the objective signs of dry eye. The most popular beauty procedure regarding eyelashes might not be innocuous to eye health.

A Single Staged Reconstruction of Upper Eyelid and Eyelashes.

The upper eyelid is a complex structural part of the face that plays an important role in protecting the cornea from drying and damage to preserve vision. The eyelashes are an essential part of the upper eyelid and help in protecting the eyes from dust, foreign bodies, and sweat. Being a part of the face, which is the most noticeable part of the body, both structures hold an important role in reconstructive procedures. Reconstruction of both structures simultaneously is tricky but helps reduce the number of procedures required in achieving an aesthetically acceptable eye. Our techniques describe the use of the paramedian forehead flap with an anterior hairline to reconstruct the upper eyelid and eyelashes in a single stage in a posttraumatic near-total upper eyelid defect with a favorable outcome. Depending on the parting of the patient's hair, the anterior hairline of one side can be included in the distal edge of the flap while raising, which can be inset so that the direction and orientation of the eyelashes perfectly match. Our technique refurbishes an established technique for eyelid reconstruction to include eyelash reconstruction at the same time, thus saving time and resources without any inconvenience to the patient.

Trichiasis in cicatricial ocular surface disease: a multi-center comparison of electroepilation versus eyelash resection outcomes.

PURPOSE: To evaluate the outcomes of trichiasis (excluding entropion) management in non-trachomatous cicatricial ocular surface diseases. METHODS: This is a multicenter, retrospective study of 59 patients with trichiasis who were managed using two different techniques: electroepilation using radiofrequency (RF) cautery and eyelash resection. The assessed outcomes were residual trichiasis at 6 weeks, 6, and 12 months of follow-up and the number of procedures needed. RESULTS: 41 patients (90 eyelids) underwent electroepilation, and 18 (41 eyelids) were managed with eyelash resection. All patients belonged to either Indian or Japanese ethnicity. Most patients in both groups had Stevens-Johnson Syndrome (63.4% vs. 88.9%). The mean age (43.2 vs. 46 years), disease duration (122 vs. 192.4 months), median trichiasis grade (2 vs. 2), and involvement of upper eyelids (53/90 vs. 23/41) were similar in the two groups. At six weeks, 48.9% of eyelids that underwent electroepilation had no trichiasis, and recurrences were managed with repeat electroepilation (6 eyelids) and mucous membrane grafting (10 eyelids), and 35 eyelids opted for manual epilation, giving 67.8% success at a mean follow-up of 20 months. The eyelash resection group had 75.6% success at 6 months, and recurrences were managed using lid splitting and eyelash resection, resulting in 100% success at a mean follow-up of 79 months. More interventions were needed in the electroepilation group compared to eyelash resection. CONCLUSION: Eyelash resection of the trichiatic eyelashes achieves a better success rate than electroepilation in cicatricial ocular surface disorders. Following electroepilation, one needs multiple interventions to resolve trichiasis.

Open clinical trial evaluating the efficacy of a novel eyelash growth enhancer with peptides and glycosaminoglycans.

BACKGROUND: Eyelashes play a crucial role in self-image and ocular protection. Enhancements to their structure are of both cosmetic and clinical interest. AIMS: To assess the efficacy of a peptide and glycosaminoglycan-based eyelash enhancer serum in improving eyelash structure. PATIENTS/METHODS: This open-label clinical trial involved 30 females aged 25-65. Eyelashes were assessed at baseline (D0), 4 weeks (D28), and 12 weeks (D84) using specialized software and high-resolution imagery. Measurements included lash number, width, length, volume, arc, and angle. RESULTS: At 12 weeks, significant increases were observed in lash length (+8.3%), number (+5%), width (+10.1%), volume (+14.1%), arc (+13.4%), and angle (+28.3%) compared to baseline. Global Eyelash Assessment (GEA) scores significantly improved, and patient treatment satisfaction increased from 73.34% at D28 to 84.33% at D84. No adverse effects were reported. CONCLUSIONS: The eyelash growth enhancer serum demonstrated significant efficacy in improving eyelash structure by Week 12, with early signs of improvement evident by Week 4. The high patient satisfaction levels underscore the perceived effectiveness of the product.

Eyelash serums: A comprehensive review.

BACKGROUND: Eyelash serums, both prescription and over-the-counter, are gaining popularity for enhancing the appearance of eyelashes through various biologically active molecules. Categorized into prostaglandin analogs and non-prostaglandin analogs, these serums claim increased strength, length, luster, and thickness. Current United States law also requires no efficacy or safety assessments by the Food and Drug Administration before approving products for consumer use, potentially posing health risks for patients seeking over-the-counter eyelash enhancements. AIMS: Our aims include exploring proposed benefits and adverse effects associated with eyelash serums, while providing evidence-based clinical recommendations on their use. We aim to contribute valuable insights to the understanding of eyelash serums and their respective safety considerations. METHODS: The authors conducted a comprehensive electronic search across databases including PubMed, Embase, Cochrane Central, and Google Scholar to evaluate eyelash serum ingredients. Articles were evaluated by two independent researchers for relevance, and the ingredients discussed were analyzed and given clinical recommendations for eyelash serums based off the Oxford Centre for Evidence-Based Medicine. RESULTS: Results highlight bimatoprost's efficacy, supported by numerous studies evaluating safety and adverse effects. Other prostaglandin ingredients show potential benefits, but further studies are encouraged to enhance the understanding of respective safety profiles. While non-prostaglandins ingredients show promising data, more studies are needed due to a lack of formal evidence in eyelash serum use. CONCLUSION: As the cosmeceutical market for eyelash serums is growing, dermatologists need to be knowledgeable about evidence-based information regarding prescription and over-the-counter eyelash serum products before making recommendations to patients.

Envenomation by Eyelash Viper Bothriechis schlegelii (Berthold, 1846) in Southwestern Colombia.

INTRODUCTION: Bothriechis schlegelii is a Crotaline viperid species of Central America and Northern South America. The characteristics of its envenomation have not been well established. We present clinical characteristics of human cases evaluated and treated in a hospital in southwestern Colombia. METHODS: We evaluated data from patients who suffered Bothriechis schlegelii envenomation and were seen at Fundación Valle del Lili Hospital, Cali, Colombia between 2011 and 2022. RESULTS: Eight patients were included, with a median age of 24 years. Snakebites occurred in rural areas. Six (75%) patients were bitten on the upper extremities in relation to the arboreal habits of this animal. The most common symptoms were pain and edema (N = 8, 100%), ecchymoses (N = 2, 25%), and paresthesia (N = 2, 25%). The most common systemic findings were hypofibrinogenemia (N = 8, 100%) and prolonged prothrombin time in five patients (N = 5, 62.5%). All were treated with polyvalent antivenom for Colombian snakes, with a good response and outcome. CONCLUSIONS: Most bite sites from B. schlegelii were on the upper limbs. All patients had both local manifestations, including edema, pain, and systemic effects with hypofibrinogenemia, but none had systemic bleeding. Every patient received antivenom and had favorable outcomes.

Ocular Side Effects of Eyelash Extension Use Among Female Students of the University of Benin, Benin City, Edo State, Nigeria.

Introduction Eyelash extensions have become a trendy cosmetic procedure, especially among young female students at various universities. This study assessed the relationship between the usage pattern of eyelash extensions and the ocular side effects arising from eyelash extension use. Methods The study was conducted using 400 female undergraduate students at the University of Benin with an age range of 15-30 years and a mean age of 22.50 ± 3.79 years. This observational cross-sectional study was conducted by evaluating the usage pattern of eyelash extensions, ocular side effects, and the relationship between them. Data obtained from the participants were processed using the Pearson correlation analysis in the Statistical Product and Service Solutions (SPSS) (version 22.0; IBM SPSS Statistics for Windows, Armonk, NY) software. Results The results showed that only 16% (n=64) of the participants had any side effects before fixing eyelash extensions, while 54% (n=216) of the participants had experienced one or more side effects during/after artificial eyelash wear. The most common side effects experienced were itching (n=152, 38%), lashes pulling out (n=144, 36%), heavy eyelids (n=136, 34%), and red eyes (n=136, 34%). Other ocular side effects were grittiness/foreign body sensation (n=128, 32%), tearing (n=96, 24%), burning sensation (n=96, 24%), pain on the eyelids (n=88, 22%), misdirected lashes (n=40,10%), eyelids swelling (n=24, 6%), a boil on eyelids (n=16, 4%), and discharge (n=8, 2%). Moreover, the result showed statistically significant correlation between the usage pattern and the ocular side effects such as pain (r=0.22), itching (r=0.23), tearing (r=0.21), burning sensation (r=0.17), a boil on the eyelids (r=0.21), heavy eyelids (r=0.16), misdirected lashes (r=0.22), red eyes (r=0.15), lashes pulling out (r=0.12), eyelids swelling (r=0.18), grittiness (r=0.10), and discharge (r=0.10) (p<0.05). Conclusions It is concluded that there is a relationship between the usage pattern of eyelash extensions and the ocular side effects. Adequate and proper attention should be paid to this ever-growing cosmetic procedure's potential visual health risks.

Characteristics of bacterial community in eyelashes of patients with Demodex blepharitis.

BACKGROUND: Demodex blepharitis (DB) is a common disease of the ocular surface. The characteristics of the bacterial community in eyelash roots after Demodex infestation are still unknown. Knowledge of the characteristics of the bacterial community of eyelash follicles in patients with DB can provide valuable insights for guiding the diagnosis and treatment of DB. METHODS: Twenty-five patients with DB (DB group) and 21 non-DB volunteers (control group) were enrolled in the study. Eyelashes from the upper eyelid of the right eye were sampled, and 16S ribosomal DNA (rDNA) sequencing was performed to determine the V3-V4 regions of the microbial 16S rDNA gene within 1 month of infestation. The sequencing data of the two groups were analyzed and compared. The effect of the bacterium Burkholderia on the survival of Demodex mites was evaluated using Demodex obtained from 12 patients with DB other that the patients in the DB group. RESULTS: A total of 31 phyla and 862 genera were identified in the DB and control groups. The five most abundant phyla in the two groups were Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes and Cyanobacteria. The abundance of Actinomycetes was significantly higher in the DB group than in the control group. At the genus level, the five most abundant genera in the two groups were Pseudomonas, Burkholderia-Caballeronia-Paraburkholderia, Rolstonia and Acinetobacter; Clostridium sensu stricto 1 was abundant in the control group and Corynebacterium_1 was abundant in the DB group. Compared with the control group, the abundance of Burkholderia-Caballeronia-Paraburkholderia was 2.36-fold lower in the DB group. Linear discriminant analysis Effect Size (LEfSe) analysis revealed Burkholderia-Caballeronia-Paraburkholderia, SC_I_84_unclassified, Nonmyxobacteria and Succinvibrio to be the major biomarkers in the control group and Catenibacterium and Lachnospiraceae NK4A136 group to be the major biomarkers in the DB group. To explore the performance of these optimal marker models, receiver operational characteristic curve analysis was performed, and the average area under the curve value of Burkholderia-Caballeronia-Paraburkholderia was 0.7448. Burkholderia cepacia isolated from normal human eyelashes was fermented, and the Demodex mites isolated from patient eyelashes were cultured together with its fermented supernatant. The results showed that the fermentation supernatant could significantly reduce the survival time of the Demodex mites, suggesting the potential therapeutic value of this bacterium against Demodex. CONCLUSIONS: The composition of the bacterial community in the eyelashes of DB patients differed from that in eyelashes of healthy volunteers, revealing a decrease in bacterial diversity in infested eyelashes. This decrease may be related to the occurrence and development of DB. The supernatant of Burkholderia cepacia culture medium was found to inhibit the growth of Demodex in eyelash hair follicles, providing a new insight with potential applications for the clinical treatment of Demodex infestation.

The effects of eyelash extensions on the ocular surface.

PURPOSE: To investigate the effects of eyelash extensions on the ocular surface. METHODS: This prospective study included 32 participants with eyelash extensions in both eyes. Symptoms and clinical parameters such as conjunctival vascular density, tear meniscus height (TMH), noninvasive tear break-up time, bulbar redness, meibography, lipid layer thickness, and corneal staining were assessed in the right eyes. These measurements were taken at baseline and 1 h, 1 day, 1 week, and 1 month after eyelash extensions were applied. RESULTS: At 1 h after eyelash extensions, ocular symptoms were reported by 27 participants (84.44 %), the most common being foreign body sensation (59.38 %). However, the Ocular Surface Disease Index scores were not statistically different between baseline, 1 week, and 1 month after eyelash extension (P > 0.05). TMH increased significantly at 1 h after eyelash extensions, from 0.27 ± 0.08 mm (baseline) to 0.29 ± 0.07 mm (P = 0.02). Subsequently, TMH decreased and was the lowest at 1 week at 0.24 ± 0.08 mm. First tear break-up time and average tear break-up time decreased to the lowest at 1 week after eyelash extension, with 8.36 ± 4.6 s and 10.71 ± 4.99 s, respectively, both of which were statistically different from baseline (P < 0.05). Corneal staining score was highest at 1 h after eyelash extensions at 0.78 ± 1.34. However, there were no significant differences in the conjunctival vascular density, bulbar redness, meiboscore, or lipid layer thickness. CONCLUSION: This study demonstrates that eyelash extensions can lead to an imbalance in ocular surface homeostasis, resulting in corneal epithelial defects and short-term decreased tear film stability.

Clinical Benefits of Baricitinib Therapy According to Scalp Hair Regrowth in Patients with Severe Alopecia Areata.

OBJECTIVES: The present analyses report integrated results from BRAVE-AA1 (NCT03570749) and BRAVE-AA2 (NCT03899259) on the clinical benefits of baricitinib treatment on the basis of the amount of scalp hair regrowth through 52 weeks of treatment. METHODS: This post hoc analysis was conducted with data from patients who were treated continuously for 52 weeks with baricitinib 4 mg or 2 mg. Clinical outcomes were assessed using the Severity of Alopecia Tool (SALT) and Clinician-Reported Outcome (ClinRO) for Eyebrow (EB) and Eyelash (EL) hair. Secondary measures included the Hospital Anxiety and Depression Scale and Skindex-16 adapted for alopecia areata. At week 52, patients were classified into three subgroups: SALT ≤ 20 response, intermediate response (achieved a 30% improvement from baseline (SALT30) without a SALT score ≤ 20), or nonresponse (never achieved SALT30). The criterion of SALT30 approximates a minimal clinical meaningful response to therapy. RESULTS: At week 52, with baricitinib 4 mg treatment, the greatest (70%) improvement in EB and EL was observed in responders, but approximately 50% of patients with intermediate response and 20% of nonresponders experienced complete/nearly complete EB and EL regrowth. Improvement in emotional distress was directionally related to improvements in scalp hair regrowth, while impact on quality of life was proportionately greater for the responder subgroup. CONCLUSIONS: Clinically meaningful regrowth in eyebrow and eyelash hair can occur in the absence of complete scalp hair regrowth after treatment with baricitinib. Emotional distress and quality of life improvement is most associated with obtaining a clinical meaningful improvement in scalp hair. TRIAL REGISTRATION NUMBER: BRAVE-AA1, ClinicalTrials.gov number, NCT03570749, start date, 24 September 2018; BRAVE-AA2, ClinicalTrials.gov number, NCT03899259, start date, 8 July 2019.

Impact and Management of Loss of Eyebrows and Eyelashes.

Eyelashes and eyebrows have different functions, ranging from practical purposes such as protecting the eye apparatus from external hazards to the definition of our facial expression. For this reason, their loss could have both functional and psychological impact on patients' quality of life. Complete or partial loss can occur any time during life, and identifying the cause is mandatory to establish a correct and prompt treatment. The aim of this paper is to create a practical guide for the management of the most common causes of madarosis to the best of our knowledge.

Screening, characterization, and determination of suspected additives bimatoprost and latanoprost in cosmetics using NMR and LC-MS methods.

Recently, many new types of cosmetic illegal additives have been screened in the market. Most of the new additives were new drugs or analogues with very similar structures to other prohibited additives, which were difficult to be identified by liquid chromatography-mass spectrometry (LC-MS) only. Therefore, a new strategy is proposed, which is chromatographic separation combined with nuclear magnetic resonance spectroscopy (NMR) structural identification. The suspected samples were screened by ultra-high-performance liquid chromatography tandem high-resolution mass spectrometry (UPLC-Q-TOF-MS), followed by purification and extraction through silica-gel column chromatography and preparative high-performance liquid chromatography (HPLC). Finally, the extracts were identified unambiguously by NMR as bimatoprost and latanoprost, which were identified to be new cosmetic illegal additives in eyelash serums in China. Meanwhile, bimatoprost and latanoprost were quantified by high-performance liquid chromatography tandem triple quadrupole mass spectrum (HPLC-QQQ-MS/MS). The quantitative method demonstrated good linearity in the range of approximately 0.25-50 ng/mL (R2 > 0.9992), with limit of detection (LOD) and limit of quantification (LOQ) values of 0.01 and 0.03 mg/kg, respectively. The accuracy, precision, and reproducibility were confirmed to be acceptable.

TFOS Lifestyle: Impact of cosmetics on the ocular surface.

In this report the use of eye cosmetic products and procedures and how this represents a lifestyle challenge that may exacerbate or promote the development of ocular surface and adnexal disease is discussed. Multiple aspects of eye cosmetics are addressed, including their history and market value, psychological and social impacts, possible problems associated with cosmetic ingredients, products, and procedures, and regulations for eye cosmetic use. In addition, a systematic review that critically appraises randomized controlled trial evidence concerning the ocular effects of eyelash growth products is included. The findings of this systematic review highlight the evidence gaps and indicate future directions for research to focus on ocular surface outcomes associated with eyelash growth products.

Large Number of Eyelashes in the Lacrimal Sac Found by Dacryoendoscopy: A Case Report.

Foreign objects sometimes enter the lacrimal sac. Here, we report the case of a patient with many comb-shaped eyelashes in the lacrimal sac and discuss the potential of using dacryoendoscopy to detect and remove foreign bodies from the lacrimal apparatus. A 65-year-old woman with a teary eye underwent dacryoendoscopy. There was no abnormality in the canaliculi. The internal ostium was blocked by a large number of black, comb-shaped eyelashes. Numerous bunched eyelashes covered with small white debris were found in the upper part of the lacrimal sac. No eyelash bundles were present from the lower lacrimal sac to the nasolacrimal duct, and the mucosa was normal. The saline was able to pass through; however, the lower part of the nasolacrimal duct was narrowed into a funnel shape. We widened it with a sheath while observing the endoscopy images. Eyelashes were flushed from the lacrimal sac through the nasolacrimal duct using the sheath and saline flow. A lacrimal tube was placed for 2 months and removed, and then the patient healed without dacryocystorhinostomy.

Pinnae and facial hypertrichosis induced by cetuximab.

INTRODUCTION: Anti-EGFR targeted anti-cancer treatment is associated with various skin adverse events. Cetuximab is often associated with acneiform papules and skin disorders. Hypertrichosis cited in face pinnae and eyelash trichomegaly are seldom described. CASE REPORT: A 72-year-old female cancer patient presented deteriorating facial-pinnae hypertrichosis and eyelash prolongation post cetuximab infusion. MANAGEMENT AND OUTCOME: Consecutive cetuximab administration led to exaggerating hairy skin side effects, fully alleviated when the drug was discontinued. DISCUSSION: To the best of our knowledge, this is the first reported case of an anti-EGFR-associated diffuse pinnae hypertrichosis presentation in a female patient in literature. This distinct entity can be easily diagnosed and manipulated with early drug withdrawal. An extensive review of relevant basic molecular research is provided to increase physicians' awareness.

Prevalence of Demodex folliculorum and Demodex brevis in patients with blepharitis and chalazion.

PURPOSE: Demodex folliculorum and Demodex brevis are common ectoparasites on skin that also can lead to blepharitis and chalazion. The aim of our study is to determine the prevalence of Demodex spp. in eyelashes of patients diagnosed with chronic blepharitis and chalazion. METHODS: This study included 330 patients diagnosed with chronic blepharitis, 70 patients diagnosed with chalazion and 130 volunteers without any ocular problems. Patient eyelashes were examined under a light microscope at magnifications of × 40, × 100 and × 400. Demodex spp. were determined. RESULTS: Parasite prevalence was significantly higher in blepharitis (75.5%) and chalazion groups (70%) compared to the control group (16.2%) (p < 0.001). The prevalence of D. folliculorum in the blepharitis group and D. brevis in the chalazion group was found to be significantly higher compared to other groups (p < 0.05). The average number of mites per eyelash was found to be significantly higher in patients with Demodex positive blepharitis (p = 0.001) and in chalazion patients (p = 0.047) than in the control group. It has been determined that mite positivity increases with age in blepharitis and control groups (p < 0.05). In the group with blepharitis, it was found that mite positivity was significant in the presence of symptoms (p = 0.0001) and Demodex positivity decreased as the education level of individuals increased (p = 0.039). CONCLUSION: The results of the study show that Demodex spp infestations should be considered in chronic blepharitis and chalazion.

Heritability estimates of distichiasis in Staffordshire bull terriers using pedigrees and genome-wide SNP data.

BACKGROUND: Distichiasis is the most frequently recorded eye disorder in the Norwegian Staffordshire bull terrier (SBT). The condition is often mild but can, in severe cases, lead to pain and blindness. The current study's main purpose was to estimate the heritability based on pedigree information as well as single nucleotide polymorphisms (SNPs) to evaluate whether it is realistic to reduce the frequency by systematic breeding. The majority of the dogs had only one examination as a young puppy. To evaluate whether this early screening gave a reliable representation of the disease burden in the population, we compared the diagnosis in puppies and adult dogs. RESULTS: Our material consisted of data from 4177 dogs with an overall prevalence of distichiasis of 8.38% (CI 7.56-9.26). The prevalence in puppies examined around eight weeks of age was significantly lower than in dogs examined after 52 weeks (2.87%, CI 2.29-3.54 versus 18.72%, CI 16.71-20.87). The heritability was estimated in dogs examined after 52 weeks. We used both pedigree (1391 dogs) and genotype (498 dogs) information for the estimates. The pedigree-based heritability was ~ 0.22 (on the underlying scale ~ 0.48), while the genomic-based heritability (on the underlying scale) was ~ 0.47, and ~ 0.37 when excluding close relatives with equal affection status. CONCLUSIONS: Screening for distichiasis in puppies before eight weeks of age is not sufficient to give an accurate estimate of the prevalence, and an additional examination after one year is recommended. The heritability of distichiasis is medium to high, showing that it should be possible to reduce the prevalence by selective breeding.

Investigation of the Relationship Between Ocular Demodex Colonization and the Conjunctival Flora

Objective: This study aimed to determine whether ocular Demodex colonization leads to changes in the conjunctival flora in healthy middle-aged individuals. Methods: This study included 70 patients who applied to an ophthalmology clinic with a complaints of presbyopia. Two eyelash specimens from the lower eyelids of both eyes were obtained from each individual. In eyelash specimens were examined for Demodex spp. by direct wet smearing under microscopy. Conjunctival culture samples were cultivated on blood agar, eosin methylene blue and chocolate agar. Results: In the 38.5% of the individuals, Demodex spp. mites were found in the eyelashes, out of which 11.4% were Demodex brevis and 27.1% Demodex folliculorum. Bacterial growth was observed in 82.9% of the samples examined. The most frequently detected bacterium was Staphylococcus epidermidis (57%). Conclusion: Although Demodex spp. infestation has been shown to be related to diseases on ocular surface of eyes such as pterygium, xerophthalmia and chalazion, we did not observe that it induces changes in ocular surface flora in healthy adults.