I read the article by Yamashita and associates with interest. The article described advantages of reduced-fluence photodynamic therapy (PDT) for polypoidal choroidal vasculopathy (PCV). I would like to comment about the application of PDT in PCV. PDT is associated with several disadvantages. First, PCV often presents as multiple widely distributed lesions, so it may be difficult to treat all lesions, including multiple polyps and interconnecting vessels, with a single beam of PDT. Treatment of leaking polypoidal dilations only, without treating the entire vascular complex, can result in persistence or worsening of exudation. Second, it can be difficult to treat nodules in the peripapillary area with a round PDT beam. Third, features commonly associated with PCV such as a large PED or a large submacular hemorrhage usually are not amenable to PDT treatment. Fourth, PCV tends to recur repeatedly, so multiple PDT treatments are often necessary, which can increase the risk of long-term choroidal atrophy. Cases of massive subretinal or suprachoroidal hemorrhage have been reported soon after PDT. Even 50% reduced light-fluence PDT can produce a retinal pigment epithelial tear in pigment epithelial detachment.
Because increased vascular endothelial growth factor levels also have been observed in PCV patients, anti-vascular endothelial growth factor therapy may be beneficial for treating PCV. Recently, Kokame and associates reported stabilization of vision at 6 months with monthly intravitreal injection of ranibizumab in PCV. Lai and associates reported stabilization of vision and reduction in exudative detachment with intravitreal bevacizumab, but its limited role in regression of polypoidal lesions in indocyanine green angiography. Complete regression of polypoidal lesion in indocyanine green angiography may not be the therapeutic target, but the close follow-up is mandatory. Polyps showing washout phenomenon on indocyanine green angiography can be watched. Considering the disadvantages and economic burden associated with PDT, anti-VEGF drugs could be the preferred treatment for symptomatic PCV.