Multimodal Imaging of Quiescent Choroidal Neovascularization: Status of Retinal Pigment Epithelium

Abstract

Purpose: to study the status of retinal pigment epithelium (RPE) over the area of quiescent choroidal neovascularization (CNV) in comparison with active CNV in neovascular age-related macular degeneration (nAMD).Patients and methods: This study included 17 patients with quiescent CNV (6 males and 11 females, mean age 74.9 ± 10.0 years) and 28 patients with active CNV (8 males and 20 females, average age 69.3 ± 6.8 years). All participants received a standard ophthalmological examination, including spectral optical coherence tomography (OCT), dark-field scanning laser ophthalmoscopy (DF-SLO) and autofluorescence. Using ImageJ, the brightness of the image in the projection of the CNV was evaluated. The vascular density of the membrane was assessed using OCT angiography.Results: The vascular density of quiescent CNV was statistically significantly higher than that of active CNV with a median value of 64.5 % (95 % confidence interval (CI) 53.4–79.0 %) and 55.3 % (95 % CI 52.2–60.0 %) (p = 0.05). Image brightness in the silent membrane region was significantly lower by compared with active CNV, both according to OCT transillumination data (p = 0.004) and according to DF-SLO data (p = 0.0015). There were no differences in autofluorescence indices between active and quiescent CNV (p = 0.44).Conclusion: Multimodal imaging indicates significant loss of integrity of RPE over active CNV, which corresponds to their lower vascular density according to OCT angiography.