Photodynamic Therapy of Subfoveal Choroidal Neovascularization in Age-related Macular Degeneration With Verteporfin

Abstract

AGE-RELATED macular degeneration (AMD) is a major cause of severe vision loss in people older than age 65 years in North America and Europe.^1,2 The visual acuity loss usually results from choroidal neovascularization (CNV), the ingrowth of new vessels from the choriocapillaris.³ These new vessels are accompanied by fibrous tissue⁴ that can destroy central visual function over months to years.^5-7 In a few selected situations, laser photocoagulation of CNV can reduce the risk of severe visual acuity loss compared with no treatment. Photocoagulation is considered when the lesion is subfoveal (extends under the center of the foveal avascular zone), has well-demarcated boundaries, has evidence of classic CNV, and is small⁵; or when the lesion does not extend under the center of the foveal avascular zone (is juxtafoveal or extrafoveal) and has well-demarcated boundaries. Many of the juxtafoveal and extrafoveal cases will have subfoveal recurrences after laser photocoagulation treatment.^6,7 For cases in which photocoagulation might be considered, the benefits of laser treatment are limited, especially for subfoveal CNV, because laser photocoagulation damages viable neurosensory retina overlaying the treated CNV. Subfoveal treatment usually results in immediate, significant visual acuity loss, especially when visual acuity is better than 20/200.^8-10 Unfortunately, most patients with subfoveal CNV will not benefit from laser photocoagulation because the lesions are too large or they have relatively good visual acuity (better than 20/200), poorly demarcated boundaries, or no evidence of classic CNV.^8-10