Experimental Inhibition of Corneal Neovascularization by Photodynamic Therapy with Verteporfin

To investigate the anti-angiogenic effects of photodynamic therapy with verteporfin in a rabbit model of corneal neovascularization.One week after suturing, the localization of verteporfin in the neovascularized cornea was examined through fluorescent microscopy 1 hr after administration. Rabbits were treated with one or two times of photodynamic therapy with verteporfin at 1-week intervals. Analysis of corneal neovascularization was performed by biomicroscopic and histological examinations.Fluorescent microscopy showed green fluorescence in the vascular walls and interstitial tissue of the corneal stroma. The mean percentages of neovascularized corneal area at 3 days, 1 week, and 2 weeks after one time of photodynamic therapy were 90.3% +/- 3.5%, 71.6% +/- 6.2%, and 43.6% +/- 15.1% in treated eyes and 96.4% +/- 1.9% (p = 0.10), 88.6% +/- 4.6% (p = 0.01), and 76.8% +/- 4.4% (p0.01) in control eyes, respectively. The mean percentages 3 days, 1 week, and 2 weeks after two times of photodynamic therapy were also significantly lower in treated eyes compared with control eyes. In quantitative histological examination at 1 and 2 weeks after therapy, treated eyes showed significantly less neovascular area and number of vessels than control eyes.Photodynamic therapy with verteporfin is a safe and useful procedure to reduce experimental corneal neovascularization and can be used to inhibit angiogenesis in the cornea.