Outcome of half-dose photodynamic therapy in chronic central serous chorioretinopathy with fovea-involving atrophy

Purpose To evaluate the clinical outcomes after half-dose photodynamic therapy (PDT) in chronic central serous chorioretinopathy (cCSC) patients with pre-existent fovea-involving atrophy. Methods In this retrospective study, cCSC patients who had a window defect of the retinal pigment epithelium (RPE) on fluorescein angiography (FA), compatible with RPE atrophy, prior to half-dose PDT were included. Results Thirty-four cCSC eyes with typical findings of cCSC on multimodal imaging, and fovea-involving RPE atrophy on FA, were included. At the first visit after PDT (at a median of 1.8 months after half-dose PDT), 20 eyes (59%) had a complete resolution of SRF ( p < 0.001), while this was the case in 19 eyes (56%) at final visit (median of 11.3 months after half-dose PDT; p < 0.001). The mean BCVA in Early Treatment of Diabetic Retinopathy Study letters was 71. 2 ± 15.9 at last visit before PDT, which increased to 74.1 ± 14.1 at first visit after PDT ( p = 0.093, compared with baseline), and changed to 73.0 ± 19.1 at final visit ( p = 0.392, compared with baseline). Both at first visit after PDT and at final visit, a significant decrease in subfoveal choroidal thickness was observed ( p = 0.032 and p = 0.004, respectively). Conclusions Half-dose PDT in cCSC patients with pre-existing fovea-involving atrophy may lead to anatomical changes, but not to functional improvements. Ideally, cCSC should be treated with half-dose PDT before the occurrence of such atrophy.