Double Layer Sign and Pigment Epithelial Detachment in Patients Treated with Subthreshold Laser for Central Serous Chorioretinopathy

Central serous chorioretinopathy (CSCR) is characterized by serous detachments of the central neurosensory retina. Besides, other alterations of the retinal pigment epithelium (RPE) of the focal detachment of the RPE can occur. We explored the frequency of RPE detachment and double layer sign in OCT in our patient population, the influence of subthreshold photocoagulation (ST-LP) on these parameters and the possibility of correlations with visual acuity. We conducted a retrospective analysis of all patients who underwent ST-LP based on the diagnosis of CSCR in a German university eye clinic from 2009 to 2014. Measurements in OCT were performed regarding pigment epithelial detachment (PED) and double layer sign (DLS). 54 eyes of 49 patients were included in the study. The frequency of PEDs dropped from 66% of cases at baseline to 50% after 3 months. No significant differences in calculated areas of lift-off volume of PED were identified. The frequency of a DLS was significantly lower 8 weeks after ST-LP compared to baseline (63%, p<0.05), but not after 12 weeks. We conclude that PEDs and DLS are common in CSCR. In this study, no convincing correlation can be identified between BCVA before ST-LP or at the last visit and different characteristics of PED as well as DLS. While the area of PED becomes smaller after ST-LP, the extent of the DLS seems to increase. Further prospective studies are required, and DLS with respect to the occurrence of CNV should also be given attention.