Therapeutic response time of topical voriconazole 1% and intrastromal voriconazole 0.05% versus topical natamycin 5% monotherapy in Fusarium keratitis in rabbit

Summary Background Fungal keratitis can be more difficult to treat than bacterial keratitis with worse outcomes. Objective To evaluate the therapeutic response time of topical voriconazole combined with intrastromal voriconazole, and topical natamycin on Fusarium keratitis. Methods The stroma of corneas of twelve New Zealand White rabbits was inoculated with Fusarium sp spores. Seven days after inoculation, they were divided into 2 groups randomly. Group A was treated with topical natamycin 5% for 21 days. Group B was treated with intrastromal voriconazole 0.05% single injection at the beginning of treatment, continued with topical voriconazole 1% for 21 days. Clinical evaluations for epithelial defect size and clinical scores in each group were performed on 1st, 3rd, 7th, 10th, 14th and 21st days after treatment. Mycological examinations were performed before and after the treatment. Results After treatment, there was no statistically significant difference between natamycin and voriconazole in reducing epithelial defect size at first, second or third week after treatment ( P = .15; P = .39; and P = .90). The clinical scores on both groups also showed no statistically significant differences at first, second and third weeks after treatment ( P = .24; P = .09; and P = .32). Qualitative mycological evaluation before and after the treatment showed no statistically significant difference in KOH examination ( P = 1; P = 1) and culture in Sabouraud dextrose agar ( P = 1; P = 1). Conclusion Intrastromal voriconazole injection combined with topical voriconazole seems to give similar response time but not earlier in improving clinical presentation of Fusarium keratitis as topical natamycin.