[Fluorescein, indocyanine green and optical coherence tomography angiography in patients with native exudative age-related macular degeneration]

Abstract

Introduction: The newly developed optical coherence tomography angiography (OCT-A) has provided new means to depict the vascular plexus in neovascular age-related macular degeneration (nAMD). If these images are to be used as a basis for therapeutic decisions, it is of vital importance to classify choroidal neovascularization (CNV) as either classical or occult. This study aimed at comparing the findings in OCT-A imaging of CNV with the traditional multimodal imaging through fluorescein angiography (FLA) and indocyanine green angiography (ICGA).

Methods: For this investigation 13 eyes from 13 patients with CNV on the basis of untreated nAMD were studied using FLA, ICGA, spectral domain OCT and OCT-A. All CNV were classified on the basis of SD-OCT and OCT-A images by two independent raters. Thereafter FLA and ICGA images were analyzed to set the gold standard for the classification and the ratings were compared to the previous SD-OCT and OCT-A results.

Results: 88% of eyes were correctly classified as either classical or occult CNV on the basis of SD-OCT and OCT-A images. Based on the CNV subgroups, 93% of classical CNV were identified using OCT-A images. In contrast occult CNV was correctly classified in 83% of patients. The interrater agreement was 77%. In general it was noted that the more the retina was pathologically altered, e. g. by edema or vascular pigment epithelium detachment, the harder it became to correctly classify the CNV.

Discussion: These results show that OCT-A can be used as an interesting addition in the diagnosis of CNV in nAMD. All CNV could be visualized using OCT-A and especially classical CNV could be clearly recognized in most cases. In contrast occult CNV could be identified in slightly fewer cases.

Keywords: Choroidal Neovascularization; Exudative age-related macular degeneration; Fluorescein angiography; Indocyanine green angiography; Optical coherence tomography angiography.