Objective    To investigate the toxicity to cornea of intrastromal injection with amphotericin B in rabbits

and explore a safe range of antibiotic concentration.     Methods    Totally 20 healthy rabbits (40 eyes) were randomly divided into 5 groups with 8 eyes in each group. The eyes of group A received intrastromal injection of 0.1 ml balanced salt solution

and those of Group B

C

D and E received 0.1ml injection containing amphotericin B 5

10

15

and 20 μg respectively. Every rabbit received 4 intrastromal injections

once per 4 d. Corneal transparency

epithelial defect and corneal neovascularization were observed with slit lamp biomicroscopy

and corneal thickness was measured with ultrasonic pachymetry. In 30 d after the last injection

all rabbits were sacrificed and their corneas were removed. Pathological observations were carried out for corneal morphology

survival rate of the corneal endothelial cells and ultrastructure of corneal endothelium.     Results    In the rabbits of Group B and C

they had transparent and intact cornea

normal endothelial cells

and had no any different with those of Group A (P0.05). However

when the concentration of amphotericin B increased to 15 and 20 μg in the 0.1 ml injection

the rabbits showed edema cornea

exfoliation of corneal epithelium and severe neovascularization

With significant differences compared with Group A (P0.05).     Conclusion    Intrastromal injection of amphotericin B at the concentration of 5 or 10 μg per 0.1ml is safe to rabbit cornea.