Case Report: Burkholderia pseudomallei-Caused Sclerokeratitis.

This report is on a 45-year-old male patient without underlying disease who presented with a Burkholderia pseudomallei-caused keratoscleritis in his right eye. Slit-lamp examination revealed multiple, indistinct corneal infiltrations with subconjunctival/scleral abscesses. Corneal tissue culture was positive for B. pseudomallei and confirmed by mass spectrometry. The patient was treated with fortified ceftazidime, fortified gentamicin eyedrops, and intravenous ceftazidime injection. Penetrating keratoplasty, including intracameral ceftazidime injections, was undertaken due to corneal lesion worsening. Scleral debridement with subconjunctival ceftazidime injections were undertaken due to the progression of the scleral abscess. After 2 months, the corneal and scleral lesions were inactive, and the systemic and topical antibiotics were tapered. This is the first case report of B. pseudomallei-caused keratoscleritis with photography. The patient was seen in an endemic geographical area with multiple corneal infiltrations and subconjunctival/scleral abscess. Systemic and topical antibiotics accompanied with surgery should be considered.

Role of Immunotherapy in Pythium insidiosum Keratitis.

Pythium keratitis is a potentially devastating ocular condition. Incidence of Pythium keratitis has been reported in tropical and subtropical areas. In previous reports, there were no effective or standard treatments, and combinations of medication, immunotherapy, and surgery were proposed. Pythium insidiosum antigen immunotherapy (PIAI) showed an acceptable safety profile, but its efficacy is questionable in Pythium keratitis. This retrospective review included 10 eyes from 10 patients. All cases were confirmed diagnosis of P. insidiosum keratitis by culture and/or polymerase chain reaction. Three doses of PIAI were injected at 2-week intervals in all patients. The infiltration diameter ranged from 5.2 mm to total corneal involvement, and eight cases (80%) had hypopyon. Therapeutic penetrating keratoplasty (TPK) or scleral graft were undertaken in nine cases. Enucleation was done in one case on the first visit. A second TPK was undertaken in three cases, and two globes were saved. Two cases in the globe salvage group received voriconazole via eyedrops and intracameral injection. No case received either linezolid or azithromycin. Three of nine eye globes (33.33%) were saved. PIAI did not show efficacy in the treatment of Pythium keratitis. Radical surgery including resurgery in recurrence is an approved effective treatment. The recently reported medications may offer supportive management.

Assessing the Risk Factors For Diagnosed Symptomatic Dry Eye Using a Smartphone App: Cross-sectional Study.

BACKGROUND: Dry eye (DE) is a chronic inflammatory disease of the ocular surface of the eye that affects millions of people throughout the world. Smartphone use as an effective health care tool has grown exponentially. The "Dry eye or not?" app was created to evaluate the prevalence of symptomatic DE, screen for its occurrence, and provide feedback to users with symptomatic DE throughout Thailand. OBJECTIVE: The purpose of this study was to compare the prevalence of symptomatic dry eye (DE), blink rate, maximum blink interval (MBI), and best spectacle-corrected visual acuity (BSCVA) between people with and without symptomatic DE and to identify risk factors for symptomatic DE in Thailand. METHODS: This cross-sectional study sourced data from the "Dry eye or not?" smartphone app between November 2019 and July 2020. This app collected demographic data, Ocular Surface Disease Index (OSDI) score, blink rate, MBI, BSCVA, and visual display terminal (VDT) use data. The criterion for symptomatic DE was OSDI score ≥13. RESULTS: The prevalence of symptomatic DE among individuals using this smartphone app in Thailand was 85.8% (8131/9482), with the Northeastern region of Thailand having the highest prevalence, followed by the Northern region. Worse BSCVA (median 0.20, IQR 0.40; P=.02), increased blink rate (median 18, IQR 16; P<.001), reduced MBI (median 8.90, IQR 10.80; P<.001), female sex (adjusted OR 1.83; 95% CI 1.59-2.09; P<.001), more than 6 hours of VDT use (adjusted OR 1.59; 95% CI 1.15-2.19; P=.004), and lower than bachelor's degree (adjusted OR 1.30; 95% CI 1.03-1.64; P=.02) were significantly associated with symptomatic DE. An age over 50 years (adjusted OR 0.77; 95% CI 0.60-0.99) was significantly less associated with symptomatic DE (P=.04). CONCLUSIONS: This smartphone DE app showed that the prevalence of symptomatic DE in Thailand was 85.8%. Signs and risk factors could be also evaluated with this smartphone DE app. Screening for DE by this app may allow for the development of strategic plans for health care systems in Thailand.

Anterior Segment Optical Coherence Tomography Images in Microsporidial Keratoconjunctivitis.

PURPOSE: To describe the findings of anterior segment optical coherence tomography (AS-OCT) in patients with microsporidial keratoconjunctivitis. METHODS: The observational study included 13 eyes from 13 patients. Slit-lamp photography and AS-OCT were performed using the Swept source OCT before corneal scraping. All cases were positive for Gram-chromotrope (modified trichrome) staining for Microsporidia spp. RESULTS: Three significant AS-OCT findings were observed. First, hyperreflective dots were limited to the epithelial layers of the cornea, and second, there were no extensions into the stromal layer in all cases. Last, hyperreflective dots slightly raised above the epithelial surface were observed in most cases (12/13%, 92.3%). CONCLUSIONS: AS-OCT represents an alternative, noninvasive tool to diagnose microsporidial keratoconjunctivitis, especially if corneal scraping is not possible.

Effect of Eyelid Margin Cleaning on Conjunctival and Eyelid Bacterial Flora Before Intraocular Surgery.

PURPOSE: To compare the bacterial cultures of the lower eyelid margins and lower fornices between ocular irrigations with and without eyelid margin cleaning before intraocular surgery. METHODS: A prospective study was carried out that included 102 eyes from 51 patients undergoing intraocular surgery between December 2016 and April 2017. In each patient, the surgical eye (control group) only received ocular irrigation and the opposite eye (study group) received ocular irrigation with eyelid margin cleaning. Normal saline solution was used in all procedures. In each group, samples from the lower eyelid margins and lower fornices were cultured before and after cleaning. Povidone iodine and antibiotic eye drops were instilled after specimen collection. RESULTS: The most common bacterial isolate of all groups was Staphylococcus spp. There were no statistically significant differences of positive cultures between the control and study groups in either lower eyelid margins (Odds ratio [OR], 2.19; 95% CI, 0.84-5.72) nor lower fornices (OR, 0.93; 95% CI, 0.43-2.00). In addition, there were no statistically significant differences of positive cultures between before and after eyelid cleanings from both lower eyelid margins (OR, 2.74; 95% CI, 0.53-14.24) and lower fornices (OR, 0.73; 95% CI, 0.21-2.57). CONCLUSIONS: Eyelid margin cleaning with normal saline solution immediately before intraocular surgery did not help to decrease microbial loading on the ocular surfaces. The rate of bacterial contamination, however, was not increased which could be due to not performing eyelid compression.

Role of Confocal Microscopy in the Diagnosis of Pythium insidiosum Keratitis.

PURPOSE: To investigate the role of in vivo confocal microscopy for detection of Pythium insidiosum keratitis. METHODS: Medical records and confocal microscopy findings of 20 patients (21 eyes) with culture- or polymerase chain reaction-proven P. insidiosum keratitis diagnosed at the Khon Kaen University Eye Center from January 2009 to December 2015 were retrospectively reviewed. Confocal microscopy was performed using Nidek ConfoScan 4. The images from 21 eyes with P. insidiosum keratitis and 4 other fungal keratitides were analyzed visually for morphology of the hyphae and special characteristics that would enable physicians to distinguish P. insidiosum keratitis from other fungal keratitides. RESULTS: A total of 21 eyes of 20 patients were included in the study. Fourteen (70%) were men, and 6 (30%) were women. In vivo confocal microscopy was able to identify hyphae in 20 of 21 eyes (95%). Beaded string-like hyperreflective branching structures with mean branching angles at 78.6 degrees or thin hyperreflective long lines were found in confocal microscopy findings of P. insidiosum keratitis. The diameter of the hyphae varied from 1.5 to 7.5 µm. CONCLUSIONS: P. insidiosum keratitis is a severe progressive infectious corneal disease that causes vision loss in most patients. Confocal microscopy may provide rapid in vivo visualization of P. insidiosum hyphae in corneal tissues, but it cannot distinguish P. insidiosum from other fungal keratitides. Culture identification with zoospore induction or polymerase chain reaction remains the most reliable means to confirm the diagnosis of P. insidiosum keratitis.

Successful treatment of Chrysosporium keratitis with voriconazole.

OBJECTIVE: To report a patient with severe Chrysosporium keratitis successfully treated by voriconazole. METHOD: Case report. RESULTS: A 37-year-old healthy male presented with irritation, pain and reduced vision in his left eye after mud contamination. Examination demonstrated corneal stromal infiltration, endothelial plaque and hypopyon. Corneal scrapings demonstrated numerous septate hyphae, and specimen cultures were positive for Chrysosporium sp. The lesion did not respond to aggressive topical 5% natamycin, 0.15% topical amphotericin B and oral itraconazole. The patient was then treated by topical 1% voriconazole every hour. Intracameral and intrastromal voriconazole injections (50 µg/0.1 mL) were also undertaken. The keratitis was significantly improved after voriconazole. CONCLUSION: To the best of the authors' knowledge, this is the first report on the use of voriconazole for Chrysosporium keratitis. Voriconazole may be an effective alternative to conventional antifungal agents in some cases of fungal keratitis. It should be considered before shifting to therapeutic keratoplasty.

Penicillium keratitis in a HIV-infected patient.

A 36-year-old HIV-positive man presented with symptoms of redness, blurred vision and foreign body sensation in his right eye for 3 months. The slit lamp examination revealed deep stromal infiltration with a feathery margin in an otherwise minimal anterior chamber reaction. A corneal scraping was negative. Confocal microscopy demonstrated an abnormal large hyper-reflective oval shape in the corneal stroma. Corneal infiltration did not show improvement after topical, intrastromal and intracameral antifungal treatment. Therapeutic penetrating keratoplasty was performed to eradicate the infection. Corneal button culture and histopathological results confirmed the diagnosis of Penicillium marneffei keratitis. No recurrent infection occurred after corneal transplantation. This appears to be the first report of P. marneffei keratitis in an HIV-infected patient. Although it is an uncommon condition, it should be one of the differential diagnoses in an HIV-infected patient presenting with keratitis.

Outcome of Therapeutic Penetrating Keratoplasty Using Glycerol-Preserved Donor Corneas in Infectious Keratitis.

PURPOSE: To report the surgical outcomes and complications of therapeutic penetrating keratoplasty (TPK) using glycerol-preserved corneas in infectious keratitis. METHODS: This is a retrospective, noncomparative case series of patients with severe infectious keratitis who received TPK using glycerol-preserved corneas from 2004 to 2014 in the Department of Ophthalmology, Srinagarind Hospital, Khon Kaen University. The medical records were reviewed for baseline characteristics, visual outcomes, recurrence rate, wound integrity, secondary glaucoma, and donor cornea storage times. RESULTS: Twenty-two eyes from 22 patients were included. Age ranged from 28 to 85 years and the donor cornea sizes ranged from 7.5 to 9.5 mm. The most common causative agents were fungi (16/22, 72.7%). Eleven patients (50.0%) developed secondary glaucoma and 7 patients (31.8%) had wound leakage. Recurrence of infection was observed in 15 patients (68.2%) and 9 patients (40.9%) received enucleation or evisceration. Thirteen globes (59.1%) were saved and the final visual acuites ranged from 1/60 to light perception. The storage times of donor corneas varied between 2 days and 62 months. The length of donor cornea storage did not affect the success rate of surgical outcome. CONCLUSIONS: TPK using glycerol-preserved corneas has a high rate of secondary glaucoma and recurrence of infection with unsatisfactory visual results. These corneas may be used as temporary emergency transplants in infectious keratitis when fresh corneas are unavailable to meet demands.

Clinical Features, Risk Factors, and Treatments of Microsporidial Epithelial Keratitis.

OBJECTIVE: To report the clinical manifestations, risk factors, and treatments of microsporidial epithelial keratitis in Thailand. METHODS: Twenty eyes of 19 patients were diagnosed and the clinical presentations, risk factors, and management were analyzed. RESULTS: Of 19 patients, six patients (32%) had no apparent risk factors. Predisposing factors included soil exposure (6/19, 32%), water contamination (6/19, 32%), and eye liner (1/19, 4%). Twelve cases (63%) were detected in the rainy season. All cases presented with disseminated, punctated, elevated, epithelial keratitis. Corneal scrapings with Gram-chromotrope staining were positive in all patients. Moxifloxacin 0.5% eye drops were given and all 16 patients experienced complete resolution. Three recurrent cases were resolved with only topical moxifloxacin without corneal scraping or swabbing. CONCLUSIONS: Predisposing factors were not found in some patients; thus, corneal scraping with staining should be considered in cases having a high index of suspicion. The incidence is increased during the rainy season; therefore, clinicians should have more awareness during these times. Debridement with topical moxifloxacin eye drops, without any systemic medication, may be an effective treatment. Corneal scraping or swabbing may not be required in recurrences.

A randomized controlled trial comparing dexamethasone with loteprednol etabonate on postoperative photorefractive keratectomy.

PURPOSE: To compare loteprednol etabonate 0.5%/tobramycin 0.3% (Zylet(®)) with dexamethasone 0.1%/tobramycin 0.3% (Tobradex(®)) in terms of the epithelial healing time, postoperative visual acuity, corneal haziness score, and intraocular pressure (IOP) in postoperative treatment after photorefractive keratectomy (PRK). METHODS: This prospective, randomized, double-masked (participants and assessors blinded) controlled study included 32 patients who underwent PRK. The patients were allocated equally into 2 groups by block randomization to receive either loteprednol etabonate (Lot) or dexamethasone (Dex) for 1 month after the surgery. The epithelial healing time, uncorrected visual acuity (UCVA), corneal haziness score, and IOP were evaluated at 1 week, 1 month, and 3 months. RESULTS: The corneal epithelium was healed within 3 days in both groups; however, the epithelium was closed on the second day in 3 cases in the Lot group compared with 1 case in the Dex group. No significant differences were found for UCVA at 1 and 3 months (Fisher exact test, P>0.01). Similarly, there was no statistically significant difference in corneal haziness scores between the 2 groups at 1 and 3 months (Mann-Whitney U test, P>0.05). The number of patients experiencing significantly increased IOP (≥5 mmHg) from baseline at any visit for the Lot group (1/16 patients) was fewer than for the Dex group (3/16 patients). CONCLUSIONS: Loteprednol etabonate was effective in postoperative PRK management and was significantly less likely to produce elevations in IOP than was dexamethasone.

Treatment of asymmetrical vernal keratoconjunctivitis with supratarsal corticosteroid injection.

A 6-year-old Thai girl presented with itching, redness and copious discharge in both eyes. Slit-lamp biomicroscopy of the left eye revealed cobblestone papillae with marked ptosis while in the right eye only small papillae were observed. Punctuate epithelial keratitis was noted only in the left eye. There were no associated factors for giant papillary conjunctivitis (ie, suture or contact lens). The cobblestone papillae in the left eye persisted after maximal topical and oral antiallergic medications. Two doses of supratarsal corticosteroid (20 mg of triamcinolone acetonide) injection without any topical or oral antiallergic medications were undertaken in the left eye 1 month apart. Cobblestone papillae and punctate epithelial erosion (including allergic symptoms) were completely recovered. There was no recurrence after 18 months of follow-up. This case report indicates that using supratarsal corticosteroid injection by itself in recalcitrant vernal keratoconjunctivitis provides promising results.

Contamination risk of 100% autologous serum eye drops in management of ocular surface diseases.

PURPOSE: To evaluate the sterility and safety of 100% nonpreserved, autologous, serum eye drop treatment in patients with ocular surface diseases. METHODS: A total of 147 autologous serum bottles (294 samples) from 21 patients with ocular surface diseases were included. Seven bottles with autologous serum were prepared for each patient, and each bottle was used for only 1 day, then discarded. Two samples from each bottle were taken (before use and after 24 hours of use) and then cultured in standard media. The culture plates were held for at least 6 weeks or until no growth could be confirmed. To monitor safety, all patients were admitted and evaluated for the occurrence of infection. RESULTS: In the pretreatment group, 4 samples from 4 patients (1.36%) were positive for bacteria and 7 samples from 7 patients (2.38%) were positive for fungi. In the 24-hour-after-treatment group, 1 culture (0.34%) was positive for bacteria, and 6 samples (2.04%) from 6 patients were positive for fungi. Aspergillus spp and Fonsecaea spp were the most common organisms identified in any of the cultures. Neither clinical nor microbiological evidence of infection was demonstrated in any patient during the treatment or follow-up periods. CONCLUSIONS: Although no ocular surface infection was observed, the patients under 100% autologous serum eye drops therapy should be closely monitored for clinical evidence of fungal and bacterial infections.

Outbreak of Pythium keratitis during rainy season: a case series.

PURPOSE: To describe typical clinical and laboratory characteristics of severe fungal keratitis caused by Pythium insidiosum during the rainy season in Northeast Thailand and to report the efficacy of P. insidiosum vaccine in the treatment of Pythium keratitis. METHODS: A series of hospital-based consecutive cases of Pythium keratitis were diagnosed and treated at Srinagarind Hospital (Khon Kaen University, Khon Kaen, Thailand). The clinical presentations, diagnostic tests, and management are described. RESULTS: Severe fungal keratitis caused by P. insidiosum was diagnosed in 5 eyes of 4 patients between May 2009 and July 2009. All cases had a history of fungal keratitis after being exposed to contaminated water. Upon slit-lamp examination, subepithelial and superficial stromal opacities were observed in a reticular pattern in all cases. Pythium insidiosum was identified and confirmed by both microbiological culture and polymerase chain reaction. Clinical worsening was detected after conventional treatment with antifungal agents. Therapeutic penetrating keratoplasty with either donor cornea or scleral graft was performed together with topical antifungal administration and P. insidiosum vaccination. Subsequent evisceration was performed in 1 eye. CONCLUSIONS: An outbreak of Pythium keratitis in Northeast Thailand was reported. Distinctive clinical features are a suggestive clue for early diagnosis. Combination treatment including topical antifungal agents, radical surgery, and P. insidiosum vaccine may be considered for the management of Pythium keratitis.

Randomized controlled trial of subconjunctival bevacizumab injection in impending recurrent pterygium: a pilot study.

PURPOSE: To investigate the efficacy and safety of subconjunctival bevacizumab injection for the treatment of impending recurrent pterygium. METHODS: A prospective, randomized, single-masked, controlled trial was conducted in 80 patients with impending recurrent pterygium. Patients were randomized into 4 groups using random tables: 20 patients served as a control and treatment groups received a single intralesional injection of 1.25 mg (20 patients, group 1), 2.5 mg (20 patients, group 2), or 3.75 mg (20 patients, group 3) of bevacizumab. Topical 0.1% fluorometholone and ocular lubricant were administered 4 times daily for 1 month in all groups. Severity of impending recurrent pterygium graded by photographic assessment (at baseline, 3 days, 1 week, and 2, 4, 8, and 12 weeks after treatment) and true recurrence were the main outcome measures. RESULTS: At 3 days, the conjunctival injection significantly decreased in all treatment groups (P < 0.01). A significant decrease in the conjunctival injection was still observed until 2 and 4 weeks in only groups 2 and 3, respectively (P < 0.05). The conjunctival hyperemia appeared to increase back to baseline at later time points. No significant difference in the mean severity score among the groups was observed. True recurrence was found in 62 patients with no statistically significant difference among the groups. No serious ocular or systemic adverse events were seen. CONCLUSIONS: A single subconjunctival bevacizumab injection seems to only partially and transiently decrease conjunctival vascularization in impending recurrent pterygium in a dose-dependent manner. This treatment does not cause regression or reduce the recurrent rate of impending recurrent pterygium.

A randomized controlled trial of intralesional bevacizumab injection on primary pterygium: preliminary results.

PURPOSE: To evaluate the efficacy and safety of intralesional injection of bevacizumab on primary pterygium treatment. METHODS: In this randomized controlled trial, each primary pterygium patient was randomized to receive either an intralesional injection of bevacizumab 2 mg (1 mg/0.04 mL) or a combination of topical antihistamine (antazoline HCl 0.05%) and vasoconstrictor (tetrahydrozoline HCl 0.04%) as a control. The main outcome measurements were symptoms and signs (including eye irritation, epiphora, redness, amount of discharge, inflammation and elevation of pterygium, and percentage of corneal pterygium area). RESULTS: A total of 74 pterygium eyes in 66 patients were randomized and allocated into a treatment group (N = 34) and a control group (N = 40). In the treatment group, there was a statistically significant reduction of symptoms (including irritation, photophobia, epiphora, redness, discharge, and blurred vision) and signs (inflammation and corneal pterygium area) compared with the baseline, up to at least 6 months. Between the treatment and control groups, no significant differences were found for all visits with respect to the (1) symptoms, (2) signs, and (3) percentage of corneal pterygium. CONCLUSIONS: Intralesional bevacizumab may have a therapeutic effect on symptoms and signs of primary pterygium for at least 6 months (ie, the follow-up period), with no serious ocular or systemic adverse effects.

2.5% and 10% phenylephrine for mydriasis in diabetic patients with darkly pigmented irides.

OBJECTIVE: To compare the clinical efficacy and systemic side effects of2.5% and 10%phenylephrinefor mydriasis in diabetic patient with darkly pigmented irides. MATERIAL AND METHOD: A prospective randomized double-blind controlled trial was conducted. One hundred diabetic patients were randomly allocated into 2.5% and 10% phenylephrine groups by block randomization. Pupil diameter, blood pressure and heart rate were measured before and after eye drop instillations. RESULTS: The mean pupil diameters after instillation in the right eye were 7.05 +/- 0.71 mm (2.5% phenylephrine group) and 7.40 +/- 0.72 mm (10% phenylephrine group, p = 0.02) and in the left eye were 7.05 +/- 0.72 mm (2.5% phenylephrine group) and 7.39 +/- 0.72 mm (10% phenylephrine group, p = 0.02). There was no clinically significant difference in mean heart rate, mean systolic and diastolic blood pressure. CONCLUSION: In diabetic patients with darkly pigmented irides, 10% phenylephrine is more effective than 2.5% phenylephrine with statistical significance. The authors recommend a single dose of 10% phenyleprine for mydriasis in these patients. However the lower concentration is recommended for use in those who exhibit a higher prevalence ofsignificant vascular disease and autonomic dysfunction and seem to be susceptible to severe adverse reaction of phenylephrine.

Effects of topical anti-inflammatory agents in a botulinum toxin B-induced mouse model of keratoconjunctivitis sicca.

PURPOSE: The aim of this study was to compare the effects of topical nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroid, doxycycline, and artificial tears for the treatment of ocular surface damage in the Botulinum toxin B (BTX-B)-induced mouse model of dry eye. METHODS: CBA/J mice were randomized into 2 experimental groups of 35 animals each. The control group received a transconjunctival injection of 0.05 mL of saline into the left lacrimal gland, and another group was injected with 0.05 mL of 20 milliunits BTX-B solution (SPSS, Inc., Chicago, IL). Three (3) days after intralacrimal gland injections, each group was equally randomized into 7 subgroups (n=5 each) to receive treatment unilaterally into their left eyes with topical artificial tears (0.5% carboxymethylcellulose sodium), 0.1% fluorometholone, 0.1% nepafenac, 0.4% ketorolac, 0.09% bromfenac, 0.1% diclofenac, or 0.025% doxycycline. Tear volume, ocular surface changes, and spontaneous blink rate were evaluated in each of the 14 experimental subgroups. RESULTS: Topical fluorometholone, nepafenac, and doxycycline significantly improved corneal surface staining in the BTX-B-injected mice within 2 weeks of treatment. Topical ketorolac, diclofenac, and bromfenac, applied twice-daily, partially reduce corneal staining, and did so more slowly by the 4-week time point. In comparison, topical artificial tear-treated mice did not demonstrate significant improvement of the corneal surface at any time point. Aqueous tear production in the BTX-B-injected fluorometholone-treated group started to return to baseline level within 2 weeks, although not significantly. Meanwhile, BTX-B-injected mice treated with artificial tears, topical NSAIDs, and doxycycline still exhibited a reduction in tear production up to 4 weeks. No significant differences in blink rate between the control and study groups undergoing the various treatments were noted at all time points. CONCLUSIONS: This study suggests the potential usefulness of topical NSAIDs, corticosteroid, and doxycycline for the clinical treatment of ocular surface epithelial disorders associated with dry eye.

Effect of topical olopatadine and epinastine in the botulinum toxin B-induced mouse model of dry eye.

PURPOSE: The aim of this study was to compare the effect of topical olopatadine, epinastine, and lubricant eye drops on dry eye ocular surface disease in the botulinum toxin B (BTX-B)-induced mouse model of keratoconjunctivitis sicca. METHODS: CBA/J mice were randomized into 3 experimental groups of 10 animals each. All mice received a transconjunctival injection of 0.05 mL of 20-mU BTX-B solutions into the left lacrimal gland. Three (3) days after intralacrimal gland injections, each group received treatment with twice-daily topical lubricant as a control, 0.1% olopatadine, or 0.05% epinastine eye drops. To monitor the progression of dry eye tear production, an ocular surface fluorescein staining score was evaluated in each of the 3 experimental groups. RESULTS: Three (3) days after the intralacrimal gland injection of BTX-B, aqueous tear production was significantly decreased (1.95+/-0.64 mm), compared to baseline level (2.69+/-0.66 mm; P<0.001). Similarly, there was a statistically significant increase in the proportion of mice with a corneal staining score of 2 or greater at 3 days postinjection, compared to the preinjection value (P<0.001). There were no statistically significant differences in aqueous tear production between the 3 different medication groups at all time points. Aqueous tear production in neither the olopatadine nor the epinastine-challenged groups was further decreased compared to the lubricant-treated group. Difference in the proportion of mice with a low- and high corneal staining score between the control and study groups did not reach statistical significance throughout the 4-week experimental period. In addition, changes in corneal fluorescein staining of the olopatadine group versus the epinastine group did not show a statistically significant difference. CONCLUSIONS: Topical olopatadine and epinastine do not cause significantly additional damage to the compromised ocular surface secondary to dry eye after continuous 4-week, twice-daily application. Topical olopatadine and epinastine appear to have comparable effects on aqueous tear-production and corneal-surface changes in this mouse model.