Natural history of minimally classic subfoveal choroidal neovascular lesions in the treatment of age-related macular degeneration with photodynamic therapy (TAP) investigation - Outcomes potentially relevant to Management - TAP report no. 6

Objective: To determine if there is a rationale for monitoring patients with age-related macular degeneration who have a minimally classic subfoveal choroidal neovascular lesion and do not receive treatment at initial examination. Methods: Participants assigned to placebo who had a minimally classic lesion composition at baseline were identified from the TAP Investigation. Fluorescein angiograms at baseline and follow-up examinations from these participants were reviewed by photograph reading center graders to determine if any follow-up angiograms had converted from a minimally classic lesion composition to a predominantly classic lesion composition. Main Outcome Measures: Proportion of minimally classic lesions at baseline that converted to a predominantly classic lesion composition, time of this conversion, and visual acuity and lesion size at the time of conversion. Results: Of the 207 patients assigned to placebo in the TAP Investigation, 98 were judged to have a minimally classic lesion at baseline in the study eye when the fluorescein angiograms were reviewed in 2001. Of these 98 patients, 39 (40%) had lesions that converted to a predominantly classic lesion composition, including 21 by the month 3 examination. At the time of conversion, 32 (82%) lesions were no greater than 9 disc areas, including 20 (51%) with visual acuity of 20/200 or better. Conclusions: These data would suggest that patients with minimally classic lesions, in whom no therapy is recommended initially, should be monitored so that potential conversion to a predominantly classic lesion can be identified promptly and verteporfin therapy considered.