Analysis of macular sensitivity using multifocal electroretinogram and microperimetry in central serous chorioretinopathy patients after half‐dose photodynamic therapy

Abstract

PurposeTo evaluate macular functional changes using multifocal electroretinography and microperimetry after half‐dose photodynamic therapy with verteporfin (HD‐PDT) in acute and chronic central serous chorioretinopathy (CSC) patientsMethodsThe charts of 101 CSC patients submitted to half‐dose PDT were reviewed. A total of 117 eyes with acute or chronic CSC underwent half‐dose PDT using 3 mg/m2 verteporfin infused over 10 min. Serial recordings of BCVA using the ETDRS charts, macular thickness using OCT and retinal sensitivity using both microperimetry (MP) and mfERG were performed at baseline and at 3, 6, 12, 18, 24, 36, 48, 60 and 72 months after treatment. A longitudinal assessment for each of these parameters and a Spearmen's correlation analysis between them was performed.ResultsCompared to baseline, a significant increase in N1, P1 and N2 mean amplitudes was registered after HD‐PDT, as well as a significant decrease in N1, P1 and N2 mean implicit times, both for central and peripheral rings. A correlation analysis showed significant correlations between BCVA and the first‐order component of retinal response for the most central ring (<2°). Significant correlations were also found between P1 implicit time and mean central macular thickness both at 36 (p = 0.030) and 72 months (p = 0.037). Central 4 degrees retinal sensitivity significantly correlated with N1 amplitude ratio at 72 months (p < 0.01) and P1 implicit time differences at 6 (p = 0.013) and 12 months (p = 0.014).ConclusionsmfERG demonstrated an increased retinal sensitivity in PDT‐treated CSC patients. Changes in BCVA, central macular thickness and central retinal sensitivity significantly correlated with the mfERG responses. HD PDT treatment improved both structural and functional outcomes and mfERG is an important objective parameter to evaluate functional changes in follow‐up.