Purpose:
"En-face" is an emerging imaging technique derived from spectral domain optical coherence tomography (OCT). It produces frontal sections of retinal layers, also called "C-scan OCT". Outer retinal tubulations (ORT) in age-related macular degeneration are a recent finding evidenced by spectral-domain OCT. The aim of this study was to analyze ORT with "en-face" OCT.
Methods:
OCT scans of the macula were performed on 20 consecutive patients with a diagnosis of AMD, who presented outer retinal tubulations. All OCT were analyzed using "en-face" technique with Spectralis HRA+OCT (Heidelberg Engineering, Heidelberg, Germany).
Results:
Of 20 analyzed eyes, 13 presented neovascular AMD and 7 presented geographic atrophy. Among the neovascular AMD eyes, the most frequent ORT pattern on "en-face" OCT was a branched network organized around a central starting point, that we call pseudodendritic. In all cases of geographic atrophy, this tubular network was located at the edge of the retinal thinning, along to the ring of elevated autofluorescence, as seen in fundus autofluorescence. In 2 cases, invaginations of ORT inside the atrophic area were observed. Cystoid macular edema was observed in 6 cases, indicating neovascular reactivation. In all eyes with exudative AMD, a choroidal fibrovascular scar could be identified on en-face scans.
Conclusions:
"En-face" OCT is a highly valuable tool for the diagnosis and follow-up of macular disease. ORT viewing by this technique demonstrates the extent of outer retinal layers alterations in AMD. It also contributes to improve our understanding of their physiopathogenic mechanisms.
Keywords: age-related macular degeneration • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • imaging/image analysis: clinical