We read with great interest the case series presented by Chan et al,1 and agree that vascularised pigment epithelial detachments (vPEDs) do not flatten easily with anti-vascular endothelial growth factor (VEGF) treatment. As the authors discuss, the prospect of using a higher than conventional dose to treat this type of choroidal neovascular membrane needs evaluation, however, we question whether the cases demonstrated did in fact have vPEDs.

Case 1 shows a well-defined circular smooth area of fluorescence consistent with a serous PED next to an area of retinal pigment epithelial mottling. This may represent an adjacent area of occult, and or atrophy, judging from the colour photograph and optical coherence tomography (OCT). It is most likely that this is a retinal angiomatous proliferation (RAP) lesion that can respond well to conventional dose anti-VEGF treatment. Case 2 also appears to show serous PED. With Case 3 it is reported that there is a retinochoroidal anastomosis at the margin of the vPEDs. The colour photograph and OCT suggest that the lesion is a serous PED associated with RAP. Again in our experience this would settle well with conventional dose anti-VEGF treatment.2

Vascularised PEDs have been defined as areas of irregular elevation of the pigment epithelium and consist of a stippled hyper fluorescent appearance on angiography. These are not usually as bright or discrete as serous RPE detachments in the early phase of angiography.3, 4 Furthermore, they gradually brighten and the vascular network might be visible on ICG.

Serous PEDs can occur without a vascular component in the context of lots of drusen and do not respond to ranibizumab. They also can occur with RAP, with polypoidal choroidal vasculopathy and as part of a mixed ‘wet’ AMD picture. Indocyanide green angiography (ICG) can be useful to identify the lesion type but is best performed with high-resolution ICG with early video, such as is possible with the Heidelberg systems. As no ICG is shown, it is hard to comment on the quality of what was seen.

It is pleasing to see that the cases reported all did well but we would be interested to know whether the authors had any other cases of suspected vPED that did not respond or indeed the outcome of other types of choroidal neovascularisation that were also treated with high-dose ranibizumab. We agree that further analysis of a larger cohort is required but would require strict inclusion criteria on what constitutes a vPED before recommending monthly high-dose ranibizumab.