Short-term reaction of choroidal neovascularization and choriocapillaris to photodynamic therapy in age-related macular degeneration

To identify the number of primary angiographic nonresponders to photodynamic therapy (PDT) with verteporfin, to determine the rate and speed of reperfusion of choroidal neovascularization (CNV) within a short observation period of only 5 weeks, and to examine the reaction of the underlying choroidal vessels. PDT according to the TAP regimen was carried out in 36 eyes with subfoveal classic CNV secondary to age-related macular degeneration. The response to PDT was examined 1 (T1) and 5 (T2) weeks following treatment. At all visits distant visual acuity was measured and both fluorescein and indocyanine green angiography was carried out. One week after treatment (T1), complete closure of classic CNV had not been achieved in 17% of eyes (primary angiographic nonresponders). At T2, 91% of eyes showed reperfusion of the CNV. In 83% of the primary angiographic nonresponders the CNV size was larger than before treatment. Choroidal shadowing was present in 82% at T1 and in 48% at T2. Primary angiographic PDT nonresponders are relatively rare; however, in contrast to former reports, they exist and can be identified by follow-up examination 1 week after PDT. Recurrence of leakage occurred earlier than expected and may require closer follow-up and earlier retreatment than recommended by the TAP trial.