Choroidal neovascularization (CNV) is a pathologic feature of many eye diseases that may lead to severe visual loss, especially in patients with age-related macular degeneration(AMD). Although clinical studies have shown the beneficial role of laser photocoagulation for patients with well-defined or classic CNV, the vast majority of patients with exudative AMD are untreatable. In addition, 50% of cases amendable to treatment with laser photocoagulation recur within 1-to- 2 years after treatment. Therefore, better treatment modalities are needed which provide highly selective and finely controlled destruction of the CNV while minimizing damage to sensory retina. The results of the Phase I studies clearly indicated the potential usefulness of using photodynamic therapy (PDT) with tin ethyl etiopurpurin (SnET2) for the treatment of small blood vessels while minimizing damage to the large choroidal vessels and overlying retinal structures. The objective of this Phase II Proposal is to build upon the research efforts initiated in Phase I and focus on the treatment of CNV.