Background: In neovascular age-related macular degeneration, new vessels grow under the retina, distorting vision and leading to scarring. This is further exacerbated if the blood vessels leak. Photodynamic therapy, originally used in cancer treatment, has been investigated as a way to treat the neovascular membranes without affecting the retina.
Objectives: The aim of this review is to examine the effects of photodynamic therapy in the treatment of neovascular age-related macular degeneration.
Search strategy: We searched for trials in the Cochrane Controlled Trials Register - CENTRAL (which includes the Cochrane Eyes and Vision Group specialised register), MEDLINE and EMBASE. We used the Science Citation Index to search for reports that cited relevant study reports. We contacted experts in the field and we searched the reference lists of relevant studies for further trial reports.
Selection criteria: We included randomised trials of photodynamic therapy in people with choroidal neovascularisation due to age-related macular degeneration.
Data collection and analysis: Two reviewers extracted the data independently. As only one trial met the inclusion criteria, meta-analysis was not performed.
Main results: One published trial was identified which randomised 609 participants. Outcome data were available at 12 and 24 months after the first treatment. Participants in the treatment group received an average of 3.4 treatments in the first year, and 2.2 in the second year. The relative risk of losing three or more lines of visual acuity at 24 months comparing the intervention with the control group was 0.75 (95% confidence interval 0.65 to 0.88). The relative risk of losing six or more lines of visual acuity at 24 months comparing the intervention with the control group was 0.61 (95% confidence interval 0.45 to 0.81). The results at 12 months were similar to those at 24 months. Subgroup analyses suggest that the benefits may be confined to people with no occult choroidal neovascularisation.
Reviewer's conclusions: Photodynamic therapy in people with classic choroidal neovascularisation due to age-related macular degeneration is effective in preventing visual loss. This evidence is drawn from a subgroup analysis of 143 participants in one trial. Outcomes and potential adverse effects of this treatment should be monitored closely. There is no evidence that photodynamic therapy is beneficial for people with evidence of occult choroidal neovascularisation. These people should be offered treatment only in the context of a randomised trial.