Ultrasound-Enhanced Drug Delivery for Treatment of Acanthamoeba Keratitis

Reaching sufficient amounts of therapeutic agents in ocular tissues is a major challenge in ophthalmology. In this study, we examined the effects of ultrasound application for delivery of polyhexamethylene biguanide for treatment of Acanthamoeba keratitis. Ultrasound intensities of 0.5 - 0.8 W/cm² and frequencies of 400 - 600 kHz were tested with exposure durations of 1 - 5 minutes. Light microscopy was used to determine the ultrasound-induced structural changes in the cornea. All groups showed increases in drug concentration, up to 2.36 times, passing through the cornea, with the 600 kHz treatment groups reaching statistical significance. Structural changes were observed in the epithelial layer of the cornea, but the stroma and endothelium remained mostly unaffected.