Morphological integrity of the outer retinal layers and visual prognosis in chronic central serous chorioretinopathy after half-dose photodynamic therapy: a qualitative SD-OCT analysis

Abstract

The study aims to investigate the morphological integrity of the outer retinal layers (ORLs) (an ellipsoid layer (EL) + external limiting membrane) and visual prognosis in chronic central serous chorioretinopathy (CSCR) with subretinal fluid (SRF) completely resorbed after half-dose photodynamic therapy (HD PDT) using enhanced-depth imaging (EDI) spectral domain optical coherence tomography (SD-OCT). This retrospective study included 40 eyes of 38 chronic CSCR patients treated with HD PDT between December 2012 and June 2016. However, only 34 eyes (85%) with complete SRF resorption 3 months after HD PDT had their 6th and 12th month data analyzed. Morphological integrity of the ORLs was further analyzed in relation to best-corrected visual acuity (BCVA) and disease duration. Thirty-four eyes of 34 patients (male/female: 82.35/17.65%) with mean age of 49.90 ± 7.80 (32-61) years were studied. The mean logMAR BCVA improved significantly from 0.52 ± 0.31 at baseline to 0.34 ± 0.36 and 0.26 ± 0.26 at the 6th and 12th months after HD PDT, respectively (p < 0.001). The proportion of eyes with completely normal morphological ultrastructural integrity of the ORLs was 44.12% at the 6th month, which increased to 64.71% at the 12th month after HD PDT. However, the EL morphological disruption was associated with significantly lower mean logMAR BCVA 12 months after HD PDT (p = 0.029). The disease duration had no effect on mean logMAR BCVA gain. Even after complete resorption of serous neurosensory retinal detachment after HD PDT in chronic CSCR, the ORLs, especially the EL, may not be anatomically restored. The EL morphological ultrastructural integrity seems to be the most important factor influencing visual prognosis.