RETINAL OPTICAL COHERENCE TOMOGRAPHY IMAGING BIOMARKERS: A Review of the Literature

Abstract

Purpose: The aim of this literature review was to summarize novel optical coherence tomography (OCT) imaging biomarkers that have recently been described in the literature and are frequently encountered clinically.

Methods: The literature was reviewed to identify novel OCT biomarkers reported to date. A descriptive summary of all terms and representative illustrations were provided to highlight the most relevant features.

Results: Thirty-seven OCT terminologies were identified. The vitreomacular interface disorder group included the four stages of epiretinal membrane, macular pseudohole, tractional lamellar hole (LH), degenerative LH, cotton ball sign, and foveal crack sign. The age-related macular degeneration group included outer retinal tubulation, multilayered pigment epithelial detachment, prechoroidal cleft, onion sign, double-layer sign, complete outer retinal atrophy, complete retinal pigment epithelium and outer retinal atrophy, and reticular pseudodrusen. The uveitic disorder group consisted of bacillary layer detachment, syphilis placoid, rain-cloud sign, and pitchfork sign. The disorders relating to the toxicity group included flying saucer sign and mitogen-activated protein kinase (MEK) inhibitor-associated retinopathy. The disorders associated with the systemic condition group included choroidal nodules and needle sign. The pachychoroid spectrum group included pachychoroid and brush border pattern. The vascular disorder group included pearl necklace sign, diffuse retinal thickening, disorganization of retinal inner layers, inner nuclear layer microcysts, hyperreflective retinal spots, paracentral acute middle maculopathy, and acute macular neuroretinopathy. The miscellaneous group included omega sign (ω), macular telangiectasia (type 2), and omega sign (Ω).

Conclusions: Thirty-seven OCT terminologies were summarized, and detailed illustrations consolidating the features of each biomarker were included. A nuanced understanding of OCT biomarkers and their clinical significance is essential because of their predictive and prognostic value.