The meta-analysis of the TAP and VIP studies was a retrospective analysis in which lesion size, composition and visual acuity at baseline were considered, as well as possible relations between these parameters and study results.

The objective of this meta-analysis was to explain the apparent discrepancies found between the TAP and VIP study results, considering the following:

- in the TAP study, treatment was found to be beneficial in predominantly classic and occult lesions, whereas it was found not to be beneficial in minimally classic lesions;

- in the VIP study, treatment of occult lesions was found to be more beneficial in small lesions (≤4 disc areas) and/or visual acuity <20/50.

This meta-analysis revealed that the most important factor in predicting final visual acuity in patients treated with PDT appears to be lesion size.

Therefore, treatment of small lesions (≤4 disc areas) will be beneficial for all types of lesions, including occult lesions with no classic component, provided lesions are recent.

Regarding classic membranes, treatment benefits extend to lesions > 4 DA and non-recent lesions.