Chorioretinal folds: A review and update of new and old etiologies

Chorioretinal or choroidal folds are wrinkles or undulations involving contiguous tissues including the anterior choroid, Bruch membrane, the retinal pigment epithelium, and in some cases the overlying neurosensory retina. These folds consist of alternating light and dark lines that may radiate from the optic disc or can be isolated to the macula or periphery. Chorioretinal folds can be the result of primary or secondary etiologies. Primary chorioretinal folds are due to hyperopia or idiopathic causes. Secondary folds are the result of secondary processes, such as mass compression, traction, or hypotony. Visual and anatomic outcomes and management strategies depend on the etiology of the folds. Multimodal imaging including color fundus photography, fundus autofluorescence, optical coherence tomography , fluorescein angiogram, and B-scan ultrasonography are integral to the diagnosis of chorioretinal folds and determination of the etiology. We summarize the principal mechanisms leading to chorioretinal folds and will review the diverse spectrum of etiologies, new and old. Choroidal folds-related maculopathy will also be described, a sequela of chorioretinal folds that can lead to vision loss.