To evaluate the results of half-dose photodynamic therapy (PDT) and determine the correlation between morphological changes measured by spectral-domain optical coherence tomography (SD-OCT) and visual acuity in patients with chronic central serous chorioretinopathy (CSC).

Twenty-five eyes of 25 patients with chronic CSC who had received half-dose verteporfin PDT were enrolled in the present study. The best-corrected visual acuity (BCVA), outer nuclear layer (ONL) thickness, and the integrity of the photoreceptor inner and outer segment junction (IS/OS) using SD-OCT were evaluated at baseline and at 3 and 6 months after treatment.

The neurosensory retinal detachment disappeared in all eyes 6 months after treatment. The BCVA improved significantly from 0.50 ± 0.32 to 0.31 ± 0.29 log MAR at 6 months ( p < 0.001). The average ONL thickness at the central fovea was 88.76 ± 19.95 µm at 6 months and the ONL thickness was well correlated with the BCVA (γ = -0.64; p = 0.001). There was no significant correlation between the status of IS/OS and the BCVA.

Half-dose PDT is effective in treating chronic CSC resulting in visual improvement and complete resolution of neurosensory retinal detachment. The ONL thickness which was positively correlated with the BCVA could be an indicator for visual prognosis of chronic CSC.