Sequential combined photodynamic and feeder vessel treatment reduces the number of photodynamic re-treatments of choroidal neovascularization in age-related macular degeneration

Purpose: Photodynamic therapy (PDT) has demonstrated to significantly modify the natural course of age-related macular degeneration complicated by some types of choroidal newvessels (CNV), even though multiple treatments are generally required. It has been also observed that the feeder vessels of the CNV become more visible after PDT. The aim of this study was to verify if PDT followed by feeder vessel treatment (FVT) can reduce the need of repeated PDT sessions. Method: Sixty eyes of 60 patients with predominantly classic CNV were treated with PDT. By means of dynamic scanning laser indocyanine green angiography, a feeder vessel could be detected in 30 eyes (before PDT in 12 eyes, 7 days after PDT in 5 eyes, 30 days after PDT in 13 eyes). In 23 out of these 30 eyes the feeder vessel was photocoagulated with a yellow kripton laser (mean of 120 burns, 100µ, 150mW, 0.2 sec.). All 60 patients repeated angiography 3 months after PDT. Results: Thirty out of 37 eyes (95%) who received only PDT required further treatment with PDT, while 4 eyes of 23 (17%) who received both PDT and FVT required additional PDT. In the remaining 19 eyes (83%) a stable reduction of dye leakage from the CNV was evident up to 6 months after combined therapy. Conclusion: Even though effective, PDT is characterized by the need of multiple treatments which are costly and potentially harmful to the retina. Previous PDT allows better identification of the feeder vessel. This study seems to demonstrate that a sequential combined treatment, PDT followed by FVT, is able to stabilize the choroidal membrane and to reduce the need of multiple treatments with PDT.