Photodynamic therapy of subfoveal choroid neovascularization. Analysis of fixation behavior

BACKGROUND: In a prospective, randomized, placebo-controlled clinical trial, we have analyzed the pattern of fixation in patients with subfoveal choroidal neovascularization in age-related maculopathy, who have been treated with photodynamic therapy (Verteporfin). MATERIALS AND METHODS: The patients in this study were participating in the TAP trial at a study center (Lubeck). The TAP study inclusion criteria have been applied and photodynamic therapy was carried out by the TAP study standard protocol. For microperimetric analysis we used the Scanning Laser Ophthalmoscope 101 (Rodenstock). Fixation was classified into foveal and excentric fixation. In addition we quantified the area of fixation (mm2). All patients had a follow-up of 2 years. RESULTS: Out of 33 patients in the Verteporfin group, 29 showed central fixation at baseline and only 11 out of 33 had foveal fixation after 24 months. The area of fixation in this group was measured at baseline at 0.44 mm2, at 1.76 mm2 after 6 months and at 2.4 mm2 after 12, 18 and 24 months, respectively. In the placebo group 11 out of 13 patients had foveal fixation at baseline and after 24 months 2 out of 13 demonstrated central fixation. The area of fixation increased from 0.76 mm2 at baseline up to 2.4 mm2 after 6 months, to 4.9 mm2 after 12 months, to 7.1 mm2 after 18 months and finally after 24 months up to 9.61 mm2. CONCLUSIONS: Photodynamic therapy with Verteporfin does not prevent loss of central fixation in patients with subfoveal choroidal neovascularization in age-related maculopathy, however PDT has a significant stabilizing effect on the development of the area of fixation.