[Outer retinal cysts in exudative age-related macular degeneration: a spectral domain OCT study]

To describe the optical coherence tomography (OCT) findings and progression of peculiar retinal cysts that we identified in patients being followed up after anti-vascular endothelial growth factor (anti-VEGF) treatment.

This is an observational case series. All relevant data (including best-corrected visual acuity and spectral domain OCT scans) concerning exudative age-related macular degeneration (AMD) patients treated with at least three anti-VEGF intravitreal injections (IVT) during the previous 12 months were collected over a period of four months.

A total of 376 consecutive choroidal neovascularization (CNV) patients (398 eyes) were examined. Of these patients, 18 (18 eyes, 4.5%), who underwent a mean of five (range, 3 to 15) anti-VEGF IVTs, had a cystic appearance of the retina on OCT scans. These cysts were usually multiple (2 to 7) and presented as optically empty spaces bordered by a mildly reflective rim. Tiny punctate spots were seen inside or along the inner border of the cyst. The presence of these two features allowed the differentiation of these cysts from CME cavities. Usually round, the cysts could be elongated in shape and simulate a serous retinal detachment (SRD). A thin layer of degenerate retina below the cysts helps differentiate them from SRD. The cysts, varying in size from 60 to 600 μm, were always located below the outer plexiform layer and visualized over or contiguous to a fibrous and hyperreflective thickening of the choriocapillary/retinal pigment epithelial (CC/RPE) complex or over an atrophic portion of the CC/RPE complex. Their size did not change over time.

These retinal cysts are a newly reported SD-OCT finding in anti-VEGF-treated exudative AMD. They could correspond to active scavenger macrophages and must be differentiated from CME and SRD in order to avoid unnecessary anti-VEGF retreatment.