Foveal and Extrafoveal Effects of Half-Dose Photodynamic Therapy in Chronic Central Serous Chorioretinopathy: A Cohort Study.

PURPOSE To compare the efficacy and safety of foveal and extrafoveal half-dose photodynamic therapy (HD-PDT) for chronic Central Serous Chorioretinopathy (cCSC). METHODS This retrospective, cohort study included cCSC eyes submitted to HD-PDT on foveal (F) or extrafoveal (E) areas. Patients were evaluated at baseline and 12 weeks after treatment for best corrected visual acuity (BCVA) and the following spectral-domain optical coherence tomography (SD-OCT) subfoveal parameters: central macular thickness (CMT), outer nuclear layer, external limiting membrane, ellipsoid zone, interdigitation zone, choroidal thickness and subretinal fluid (SRF). RESULTS F group comprised 33 eyes (47.1%) and E group comprised 37 eyes (52.9%). Both groups showed an improvement of BCVA after HD-PDT with no significant differences in final BCVA (p = .41). CMT and SRF showed a significant improvement after HD-PDT in both groups, but the rate of disruption of the external retinal layers remained stable. During follow-up, SD-OCT parameters and the rate of anatomical success showed no significant differences regarding the treatment location. No major sequelae were noticed. CONCLUSION Foveal and extrafoveal applications of HD-PDT for cCSC showed comparable efficacy and safety.