Purpose: To evaluate the effect of elongated photoreceptor outer segment length on the visual prognosis of patients with chronic central serous chorioretinopathy after treatment using half-dose and half-fluence photodynamic therapy (reduced PDT).
Methods: The study included 36 eyes of 36 patients with chronic central serous chorioretinopathy who underwent reduced PDT and were followed up for at least 1 year. Spectral domain optical coherence tomography measurement was conducted at baseline and 12 months after reduced PDT. Thereafter, the association between the best-corrected visual acuity (BCVA) at 12 months after reduced PDT and 7 baseline variables (age, symptom duration, BCVA, outer nuclear layer thickness, elongated photoreceptor outer segment length, height of subretinal detachment, and subfoveal choroidal thickness) was evaluated. Multivariate analyses using the model selection with the corrected Akaike Information Criterion index were performed.
Results: The optimal model for BCVA at 12 months only included baseline BCVA (coefficient = 0.90, P < 0.0001) and baseline elongated photoreceptor outer segment length (coefficient = -0.0016, P = 0.034), but not outer nuclear layer thickness.
Conclusion: Elongated photoreceptor outer segment length was significantly associated with BCVA prognosis in patients with chronic central serous chorioretinopathy after reduced PDT and can be useful for predicting residual photoreceptor function during the active phase of chronic central serous chorioretinopathy.