Anatomical and functional changes in neovascular AMD in remission: Comparison of fibrocellular and fibrovascular phenotypes

Purpose: To investigate the anatomical changes and the macular function in neovascular age-related macular degeneration (AMD) eyes, according to the recognition of either fibrocellular or fibrovascular phenotype. Methods: We enrolled eyes with previously treated neovascular AMD in remission (no subretinal haemorrhage, sign of fluid in or under the retina and no treatment for at least 6 months). Subjects underwent multimodal imaging assessment and were tested for macular sensitivity using microperimetry. The study cohort was divided according to the presence of fibrosis on multicolour (MC) images, yielding two distinct phenotypic subgroups: (1) fibrocellular group and (2) fibrovascular group. Results: Nineteen eyes were classified as fibrocellular on MC images, while 22 eyes as fibrovascular. Mean±SD age was 73.9±11.0 years in the fibrocellular group and 75.9±7.1 years in the fibrovascular group (p=0.221). Best-corrected visual acuity was 0.7±0.5 logarithm of the minimum angle of resolution (LogMAR) in the fibrocellular group and 0.3±0.2 LogMAR in the fibrovascular group (p=0.003). On the optical coherence tomography and fundus autofluorescence evaluation, 17/19 eyes with the fibrocellular phenotype and 8/22 eyes with the fibrovascular phenotype displayed the presence of retinal pigment epithelium (RPE) atrophy (p=0.001). The perfusion density within the neovascular lesion was 28.9%±9.9% in the fibrocellular group and 44.2%±5.9 % in the fibrovascular group (p<0.0001). Conclusion: Neovascular AMD eyes in remission and with evidence of fibrocellular scar are characterised by RPE atrophy and reduced perfusion, which are associated with a higher degree of functional impairment. These findings suggest that maturation of vessels in fibrosis might be a better target in neovascular AMD treatments rather than their abolishment.