Purpose: Choroidal venous overload was recently suggested to be a pathogenetic factor in central serous chorioretinopathy (CSC). Manifestations of venous overload on ultra-widefield indocyanine green angiography (UWF ICGA) include asymmetric arterial choroidal filling (AACF), enlarged choroidal vessels (“pachyvessels”), and asymmetric venous drainage (AVD) leading to choroidal intervortex venous anastomoses (CVA) accompanied by choroidal vascular hyperpermeability (CVH). The purpose of the current study is to assess the presence of these signs of venous overload in a large cohort of CSC patients.
Methods: For the CERTAIN study, patients underwent a standardized imaging protocol including UWF ICGA. Features of choroidal venous overload were graded for each eye individually by two independent graders and – in case of disagreement – by a third grader.
Main outcome measures: Presence of AAFC, pachyvessels, AVD, CVA, and CVH.
Results: In total, 178 eyes of 91 patients were included in this study. Mean patient age was 47.6 (± 12.0) years and 75 patients (82%) were male. The 116 eyes (65%) that showed subretinal fluid were considered affected (bilateral disease in 29 patients). In affected eyes, AACF was present in 62 eyes (85% of gradable eyes), pachyvessels in 102 eyes (88%), AVD in 81 eyes (74%), CVA in 107 eyes (94%) and CVH in 100% of affected eyes. For fellow eyes, prevalence of pachyvessels (94%), AVD (67%), and CVA (90%) was similar to affected eyes, while CVH was present in 85% of fellow eyes. Inter-grader agreement was excellent for CVH (94%), and 74-82% for all other criteria. Patients with pachyvessels and AVD in one eye were more likely to also show the same characteristic in the fellow eye (odds ratios 22.2 and 9.9, p<0.01).
Conclusions: Signs of venous overload are seen in the vast majority of CSC patients, both in affected and unaffected eyes. While pachyvessels, AVD, and CVA are observed frequently, CVH was observed in all affected eyes, showed excellent inter-grader reliability and is diagnostic for CSC. This supports the concept of choroidal venous overload as a major factor in CSC pathogenesis.