Purpose To assess longitudinal changes and determine their angiographic risk factors in the fellow eyes of patients with unilateral polypoidal choroidal vasculopathy (PCV).

Methods We reviewed the medical records of 47 patients with unilateral PCV, all of whom had completed at least 12 months of follow-up. The angiographic features were evaluated including the development of active PCV over time, choroidal vessel dilation, choroidal vascular hyperpermeability, the branching vascular network (BVN) and late geographic hyperfluorescence (LGH), which was defined as a well-demarcated geographic hyperfluorescent lesion on late-phase on indocyanine green angiography (ICGA).

Results The mean follow-up period was 30.3±12.2 months. Among 47 fellow eyes, 24 (51.1%) had choroidal vascular dilation, 27 (57.4%) had choroidal vascular hyperpermeability, six (12.8%) had BVN and 23 (48.9%) had LGH. The development of active PCV was noted in nine fellow eyes (19.1%), all of which had exhibited LGH at baseline. However, PCV did not develop in eyes without features of LGH at baseline (p<0.001). The development of PCV was noted in three eyes with notification of BVN at baseline; however, PCV also developed in six eyes without apparent features of BVN (p=0.08).

Conclusion The presence of LGH on ICGA in the fellow eye appears to be a significant risk factor for the development of active PCV and may constitute the diagnosis of preclinical PCV.