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Purpose: To determine the association of type III secretion system (T3SS) genotype with antibiotic susceptibility, serotypes, and clinical manifestation of centrally located Pseudomonas aeruginosa keratitis., Methods: Clinical characteristics of P. aeruginosa keratitis cases from 2001 to 2011 were analyzed. Each strain was serotyped and genotyped for T3SS exotoxin genes. Antibiotic sensitivity and minimum inhibitory concentrations were determined with agar dilution method. Prognostic factors affecting final visual outcomes and time to re-epithelialization were analyzed using linear and Cox regression models., Results: Forty-four invasive and 28 cytotoxic strains were identified. Invasive strains occurred mostly in males (P = 0.03) with older age (P = 0.009) and ocular surgery or trauma history (P = 0.006), poor presenting (P = 0.04) and final (P < 0.0001) best spectacle-corrected visual acuity (BSCVA), and larger infiltration size (P = 0.03). Cytotoxic strains were associated with contact lens wear (P < 0.0001). Poor prognostic factors for final BCVA after adjusting for sex, age, and contact lens wear included invasive strains (P = 0.02), larger infiltration area (P = 0.02), deeper infiltrations (P = 0.02), and presence of hypopyon (P = 0.09). Factors affecting complete re-epithelialization time included invasive strains (P = 0.02), infiltration area (P = 0.01), depth (P = 0.02), and hypopyon (P = 0.03) after adjusting for age and sex. Serotypes 2, 6, and 11 were more commonly found among all isolates. A trend to increased fluroquinolone resistance is noted for invasive strains, although not reaching statistically significant difference., Conclusions: Cytotoxic strains are associated with contact lens wear while invasive strains are related to poor prognosis and increased resistance to fluoroquinolones. Clinicians should be aware of the two different genotypes of P. aeruginosa affecting prognosis., (Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.)

Purpose: We used a rabbit model to evaluate the interface embedded between the recipient corneas and transplanted donor corneal discs after non-Descemet's stripping automated endothelial keratoplasty (nDSAEK)., Methods: Unilateral DSAEK and nDSAEK surgeries were performed on New Zealand white rabbits. In vivo confocal microscopy was performed to show: the changes in corneal endothelial cells embedded between the recipient corneas and the transplanted donor corneal discs (CEEB); and the interface opacity by z profile. Immunohistochemistry were performed to evaluate the functional change of CEEB at post-nDSAEK 3 months. Transmission electron microscopy was performed to evaluate the morphology of CEEB after nDSAEK at post-nDSAEK 1, 3, and 6 months., Results: In vivo confocal microscopy showed a time-dependent decrease in the density of CEEB at postoperative 1, 2, or 3 months (P < 0.01). Interface opacity was higher in the nDSAEK group than the DSAEK group at all examination points, but the difference was statistically insignificant. At 3 months after surgery, the CEEB were negative for Na(+)/K(+)-ATPase staining. Staining with TUNEL showed apoptotic changes in some areas. During a 6-month observation, the CEEB showed a time-dependent thickening and loss of uniform thickness of cellular morphology. At 3 and 6 months post nDSAEK, extensions of the cellular processes into the donor graft stroma combined with intracellular vacuoles containing collagen-like materials were also found., Conclusions: After non-Descemet's stripping automated endothelial keratoplasty, the CEEB showed decreased density, loss of pump function, apoptosis and changed morphology. However, the interface opacity was not significantly greater compared with DSAEK eyes., (Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.)