Characteristics of fine vascular network pattern associated with recurrence of polypoidal choroidal vasculopathy.

Objective: To characterize an irregular capillary-like structure in the vascular network of eyes with polypoidal choroidal vasculopathy (PCV), and to determine whether its presence after photodynamic therapy (PDT) can be used to predict the clinical course of PCV.

Methods: We reviewed the clinical records of 29 eyes of 29 patients with PCV, who underwent PDT and confocal retinal angiographic examinations every 3 months. The images obtained before the PDT were compared with those after the PDT. The correlations between angiography findings and recurrences were evaluated.

Results: An area of fine, densely packed capillary-like vessels, named the fine vascular network, was identified within the polypoidal vascular network in 25 of 29 cases at the initial examination. The fine vascular network regressed in 23 cases (92%) after the first PDT. Thereafter, the fine vascular network remained or enlarged in 19 eyes, and 17 (84.5%) of these eyes had a recurrence of the polypoidal lesions or had exudative changes. In contrast, recurrences were found in only 2 of 10 (20%) eyes, whose fine network had regressed without a subsequent enlargement (P<0.001 compared with the former group).

Conclusions: A fine irregular vascular network is present in the majority of eyes with PCV before PDT. Its presence or expansion after PDT was significantly associated with a recurrence of PCV. Thus, we recommend that this network be monitored after treatment to determine whether a polypoidal vascular network will recur.