Corneal Ulcer Leading to Evisceration or Enucleation in a Tertiary Eye Care Center in Thailand: Clinical and Microbiological Characteristics.

BACKGROUND: Very severe corneal infection can lead to permanent visual loss, and there is still inadequate knowledge about these severe cases. OBJECTIVE: To identify clinical and microbiological characteristics of corneal ulcers resulting in evisceration or enucleation in a tertiary eye care center in Thailand. MATERIAL AND METHOD: A retrospective chart review was performed of all patients who required evisceration or enucleation due to corneal ulcer at Rajavithi Hospital, Bangkok, Thailand between October 2008 and September 2013. RESULTS: One hundred patients who underwent evisceration or enucleation as a result of corneal ulcer were included in the study. The mean age of the patients was 56.5 ± 12 years, most cases were referred from other hospitals (93%), and 13% of patients were diabetic. At presentation, visual acuity was worse than 5/200 in almost all cases (98%), and trauma (66%), especially by organic substances (36%), was the most common cause. Most cases had full thickness infiltration (81%) with mean size of 6.6 ± 2 mm. Corneal perforation was found in 18% of patients at presentation, and 60% of corneal scraping cultures were positive. Bacteria were the most common pathogens (65%), leading by Pseudomonas aeruginosa (10 cases), and the most common fungus was Fusarium spp. (7 cases). Secondary glaucoma (39%) and corneal perforation (25%) were the main ocular complications. Over half of the patients (52%) needed therapeutic or tectonic surgical intervention during admission. Following evisceration (94%) or enucleation (6%), 23 cases had wound complications that required further surgical treatment. Bacterial infection was found to increase the risk of wound complications more than infection by other pathogen groups (40.9%, p = 0.013). CONCLUSION: Despite aggressive medical and surgical treatments, very severe corneal ulcers at referral can lead to loss of an eye. Bacterial infection, especially by Pseudomonas aeruginosa, following eye trauma was the most common cause. Evisceration in bacterial corneal ulcers had greater wound complications than ulcers infected by other pathogens.

Trends in contact lens-related corneal ulcers at a tertiary referral center.

PURPOSE: To evaluate the changes and trends in the number and characteristics of contact lens-related ulcers (CLRUs) and to compare the results with those of previously published series at our institution. METHODS: Medical records of all patients diagnosed with presumed bacterial corneal ulcers seen at the Cornea Service, Wills Eye Institute, between January 1, 2004, and December 31, 2007, were retrospectively reviewed. RESULTS: Five hundred seven corneal ulcers were identified. Of these, 223 (43.9%) were contact lens (CL) related and 284 (56.1%) were not CL related. The proportion of CLRU showed a significant increase over time (P = 0.003), with significantly greater percentage of CLRU in 2006 and 2007 compared with 2004 (P = 0.004 and P = 0.005, respectively). One hundred thirty-one (58.7%) of the 223 CLRU patients were men. Many CLRUs were vision threatening, with 45.7% (92 of 201) more than 4 mm in size, 36.3% (81 of 223) associated with hypopyon, and 46.4% (103 of 222) central or paracentral in location. Pseudomonas aeruginosa was the most frequent agent isolated in CLRUs, found in 75 (63.0%) of 119 positive cultures. Soft daily-wear frequent replacement lenses were the most common lenses associated with corneal ulcers and were used in 68 (33.5%) of 203 cases. There was a history of overnight wear of CLs in more than half of the cases (121 of 223, 54.3%). Of these, 21 (9.4%) were not approved for overnight wear. CONCLUSIONS: There was a significant increase in the number of cases of presumed bacterial keratitis associated with soft CL wear over the study period from 2004 to 2007 at our institution. The significant increase in CLRU noted from 1996 to 1999 to 1999 to 2002 reported previously seems to have continued between 2004 and 2007.

Effect of chitosan-N-acetylcysteine conjugate in a mouse model of botulinum toxin B-induced dry eye.

OBJECTIVE: To evaluate the effect of a thiolated polymer lubricant, chitosan-N-acetylcysteine conjugate (C-NAC), in a mouse model of dry eye. METHODS: Eye drops containing 0.5% C-NAC, 0.3% C-NAC, a vehicle (control group), artificial tears, or fluorometholone were applied in a masked fashion in a mouse model of induced dry eye from 3 days to 4 weeks after botulinum toxin B injection. Corneal fluorescein staining was periodically recorded. Real-time reverse transcriptase-polymerase chain reaction and immunofluorescence staining were performed at the end of the study to evaluate inflammatory cytokine expressions. RESULTS: Mice treated with C-NAC, 0.5%, and fluorometholone showed a downward trend that was not statistically significant in corneal staining compared with the other groups. Chitosan-NAC formulations, fluorometholone, and artificial tears significantly decreased IL-1beta (interleukin 1beta), IL-10, IL-12alpha, and tumor necrosis factor alpha expression in ocular surface tissues. CONCLUSIONS: The botulinum toxin B-induced dry eye mouse model is potentially useful in evaluating new dry eye treatment. Evaluation of important molecular biomarkers suggests that C-NAC may impart some protective ocular surface properties. However, clinical data did not indicate statistically significant improvement of tear production and corneal staining in any of the groups tested. CLINICAL RELEVANCE: Topically applied C-NAC might protect the ocular surface in dry eye syndrome, as evidenced by decreased inflammatory cytokine expression.