We read the article by Sato and associates with interest. The article described the usefulness of combined photodynamic therapy (PDT) with verteporfin and intravitreal bevacizumab for polypoidal choroidal vasculopathy (PCV).
We 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 pigment epithelium detachment or a large submacular hemorrhage, usually are not amenable to PDT treatment. Fourth, PCV tends to recur repeatedly, so multiple PDT treatments often are 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.
Recently Kokame and associates reported stabilization of vision at 6 months, with monthly intravitreal injection of ranibizumab in PCV. Lee and associates also showed short-term improvement with intravitreal bevacizumab alone in a small series. Lai and associates reported stabilization of vision and reduction in exudative detachment with intravitreal bevacizumab, but its limited role in regression of polypoidal lesions on indocyanine green angiography. Complete regression of polypoidal lesion on indocyanine green angiography may not be the therapeutic target, but close follow-up is mandatory. Polyps showing a so-called washout phenomenon on indocyanine green angiography can be monitored. Considering the disadvantages and economic burden associated with PDT, anti-vascular endothelium growth factor drugs alone may be the preferred treatment for symptomatic PCV.