Capturing the Transition From Intermediate to Neovascular AMD: Longitudinal Inner Retinal Thinning and Factors Associated With Neuronal Loss

Abstract

Purpose To estimate the impact of transition from intermediate to exudative neovascular age-related macular degeneration (AMD) on the inner retina and to assess the relationship of clinical characteristics and optical coherence tomography (OCT) findings with inner retinal changes. Methods A total of 80 participants (80 eyes) with intermediate AMD at baseline who developed neovascular AMD within 3 months were included in the analysis. OCT scans at follow-up visits (after transition to neovascular AMD) were compared with values at the latest visit with evidence of intermediate AMD to quantify longitudinal inner retinal changes. OCT images were also reviewed for qualitative features reflecting distress of the outer retina or retinal pigment epithelium and for the presence and characteristics of exudation. Results The parafoveal and perifoveal inner retinal thicknesses were 97.6 ± 12.9 µm and 103.5 ± 16.2 µm, respectively, at baseline, and a significant increase in values was detected at the visit with first evidence of neovascular AMD (parafoveal: 99.0 ± 12.8 µm, P = 0.040; perifoveal: 107.9 ± 19.0 µm, P = 0.0007). Conversely, the inner retina was significantly thinner at the 12-month follow-up visit after initiation of the anti-vascular endothelial growth factor therapy (parafoveal: 90.3 ± 14.8 µm, P < 0.0001; perifoveal: 92.0 ± 21.3 µm, P < 0.0001). At the 12-month follow-up visit, OCT evidence of alterations of the external limiting membrane and history of previous intraretinal fluid were associated with a greater inner retinal thinning. Conclusions The development of exudative neovascularization is associated with significant neuronal loss that may be detected once the exudation is resolved. OCT analysis demonstrated a significant relationship between morphological alterations detected using structural OCT and the amount of inner neuronal loss.

Retinal neurodegeneration in age-related macular degeneration

“…19 Alternatively, a microvascular choroidal failure may be responsible for postreceptoral damage, a theory known as the “ischaemia postreceptoral hypothesis”. 37 Similarly, Woo Lee et al 38 investigated changes occurring to the inner retina in neovascular AMD eyes undergoing intravitreal anti-VEGF therapy and demonstrated a significant progressive thinning of the inner retina in these eyes. They enrolled 52 eyes of patients with exudative AMD who had been treated with at least 3 anti-VEGF injections.…”

Deep Learning in Neovascular Age-Related Macular Degeneration

“…The advanced form of AMD is characterized by the development of either macular neovascularization (MNV) or geographic atrophy (GA), which are both responsible for the majority of cases of visual impairment in eyes with AMD [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. MNV is characterized by the proliferation of abnormal blood vessels and subsequent leakage due to their immature vascular network.…”

Retinal layers changes in patients with age-related macular degeneration treated with intravitreal anti-VEGF agents

“…Neovascularization occurring in nAMD most commonly originates from the choriocapillaris, manifesting as various degrees of exudation in retinal pigment epithelium (RPE) and intraretinal fluid on OCT [ 17 ]. Although AMD is generally considered a disease of the outer retina, much research has shown that both inner and outer retinal layers change during disease progression [ 18 – 21 ]. However, retinal alterations after intravitreal anti-VEGF therapy for AMD are typically assessed in terms of visual acuity (VA) or central subretinal thickness (CST) in previous studies [ 12 , 22 ], with little emphasis on changes in individual retinal layers or only a single layer such as retinal nerve fiber layer (NFL) or ganglion cell layer (GCL) [ 23 , 24 ].…”