RISK of EXUDATION in EYES with NONEXUDATIVE POLYPOIDAL CHOROIDAL VASCULOPATHY

Purpose:To investigate the characteristics and natural history of treatment-naive nonexudative polypoidal choroidal vasculopathy (PCV) and to determine biomarkers predicting exudative conversion.Methods:Patients diagnosed with nonexudative PCV based on indocyanine green angiography and optical coherence tomography were included. Incidence of exudative conversion in nonexudative PCV patients and cumulative estimates for overall risk were assessed. Indocyanine green angiography and optical coherence tomography imaging-based features were analyzed to identify risk factors for exudative conversion.Results:The study included 42 eyes of 40 patients with nonexudative PCV. The mean follow-up duration was 54.3 ± 35.5 months. Of the 42 eyes with nonexudative PCV, exudative conversion developed in 23 eyes (54.8%) after 42.2 ± 28.3 months (range, 8-103 months). Kaplan-Meier analysis showed that the exudation-free survival at 5 years after baseline was estimated to be 53.6%. Multivariate regression analysis showed that sequentially increased protrusion of retinal pigment epithelium in the polyp area was a significant risk factor for exudation in nonexudative PCV (odds ratio = 10.16; 95% CI 1.78-57.81; P = 0.01).Conclusion:Exudative conversion has been noted in nearly half of the nonexudative PCV cases in 5 years. The progressive protrusion of polypoidal lesions on optical coherence tomography examination may be a significant biomarker for predicting the near-Term onset of exudation.