Role of 0.02% polyhexamethylene biguanide and 1% povidone iodine in experimental Aspergillus keratitis.

Abstract

To determine the efficacy of 0.02% polyhexamethylene biguanide and 1% povidone iodine in experimental keratitis. Aspergillus fumigatus keratitis was induced by corneal intrastromal injection of spores in 24 healthy rabbits that were randomly divided into four groups of six rabbits each. Drugs used were 5% natamycin (standard antifungal), 0.02% polyhexamethylene biguanide (PHMB) (test drug), 1% povidone iodine (test drug), and 0.5% hydroxypropylmethyl cellulose (HPMC) (control). The average healing times of the ulcer were 21.5 +/- 3.08 days with 5% natamycin, 27.8 +/- 2.28 days with 0.02% PHMB, 36.4 +/- 2.57 days with 1% povidone iodine, and 38.2 +/- 4.74 days with 0.5% HPMC. While no corneal perforations occurred with natamycin treatment, one perforation was noted with PHMB, three perforations were noted with povidone iodine, and five perforations were noted with controls. Polyhexamethylene biguanide (0.02%) is a moderately effective drug for experimental Aspergillus keratitis, but 1% povidone iodine is not effective.