Subretinal pigment epithelium fibrotic tissue morphological changes after a single anti-vascular endothelial growth factor injection in age-related macular degeneration.

Abstract

To demonstrate and evaluate the morphological changes of multilayered fibrovascular pigment epithelial detachment (PED) to a single anti-vascular endothelial growth factor (VEGF) injection in age-related macular degeneration (AMD). We retrospectively analysed the morphological changes of 30 eyes with exudative AMD showing fibrotic multilayered PED, between two consecutive visits. All patients had one anti-VEGF intravitreal injection at the first visit. We quantitatively analysed the different compartments within the PED and their morphological response. The mean follow-up time interval between the first and the second visit was 32.46±4.64 days. We defined three optical coherence tomography zones within the PED: a subretinal pigment epithelium inhomogeneous hyporeflective space (layer 1), a hyper-reflective band beneath layer 1 (layer 2), and a hyporeflective space between the Bruch's membrane and layer 2 (layer 3). The mean height of layer 1 was 142±44.63 and 99.30±39.79 µm at visits 1 and 2, respectively. The mean thickness of layer 2 was 101.42±46.66 and 82.76±35.24 µm at visits 1 and 2, respectively. The mean height of layer 3 was 35.77±32.77 and 5.66±8.68 µm at visits 1 and 2, respectively (p=0.009). The mean height change for layer 1 was statistically significantly higher than for layer 2 (p=0.0002). Fibrovascular PED was compartmented into three layers with different reflectivities that morphologically responded differently to a single anti-VEGF injection. Layer 2 had a statistically significantly lower response compared with layer 1, suggesting the hypothesis of a fibrotic component in layer 2.