ObjectiveTo observe the characteristic variation of the patients' inner and outer retina who had chronic central serous chorioretinopathy (CSC) after being treated of photodynamic therapy (PDT). MethodsNineteen patients with chronic CSC were recruited, including 15 eye of men and 4 eye of women, logMAR BCVA was 0.1-1.0, 0.39±0.30. Meanwhile, 24 healthy people were located in the control group. All the patients received PDT for the first time. All subjects including 24 healthy people underwent fourier domain optical coherence tomography (FD-OCT). Retinal thickness were investigated before PDT and 1, 4, 12, 20 weeks after PDT respectively. Data were recorded including inner layer and outer layer. Retinal thickness were compared in fovea (1 mm), parafovea (3 mm)and perifovea(5 mm). Paired-samples t test was used to compare retinal thickness before and after PDT. The statistical differences of patients and control group were evaluated by independent-samples t test. The correlations between the best logMAR corrected visual acuity (BCVA) was analyzed by Pearson statistical analyses. ResultsThe inner(F=13.814, 10.095, 4.689) and outer(F=9.354, 5.878, 3.978)layer fovea thickness of CSC subjects in 1, 4, 12 week was thinner, the difference was statistically significant (P < 0.05). The outer layer fovea thickness at P12(t=-3.725), parafovea of inner and outer retinal(t=-3.198, -2.722)was reduced when compared with control group, and differences have statistical sense, respectively (P < 0.05). There was correlation between logMAR BCVA and outer retinal thickness in fovea and parafovea (r=0.465, -0.728, -0.687; P < 0.05). ConclusionIn our study, the inner and outer layer retinal thickness decreased generally after the first time PDT in CSC patients.