Animal Study of Photodynamic Therapy with Verteporfin in Corneal Neovascularization

ABSTRACT

PURPOSE: To determine the efficacy of photodynamic therapy (PDT) with verteporfin (Visudyne(R), Norvatis Ophthalmics AG, Hettingen, Switzerland), a benzoporphyrin derivative, in the treatment of corneal neo-vascularization (CN) in a rabbit eye model. METHODS: CN was induced by placing instrastromal sutures in the cornea. Two weeks after suturing, verteporfin was administrated intravenously and 1 hour later, the right eye (treated group) was exposed to a laser with a 689 nm wavelength, and the left eye was used as the control. The changes in CN were analyzed using biomicroscopy and optical microscopy in twelve rabbits. RESULTS: The mean percentages of the neovascular area in the control and treated groups were 96.4 +/- 1.9% and 90.3 +/- 3.5% (P=0.009) at three days after the PDT, 88.6 +/- 4.6% and 71.6 +/- 6.2% (P<0.001) at one week, and 76.8 +/- 4.4% and 43.6 +/- 15.1% (P<0.001) at two weeks, respectively. Optical microscopy showed significant differences between the control and treated group in terms of the area and number of CN (P<0.05). CONCLUSIONS: PDT with verteporfin is a safe and effective procedure for regressing CN. However, a further study will be necessary.