Differences in structural optical coherence tomography and infrared enface images between non-exudative macular neovascularizations secondary to AMD and pachychoroid disease.

Abstract

To provide an analysis of structural optical coherence tomography (OCT) and enface infrared reflectance (IR) differences between non-exudative macular neovascularizations (NE MNVs) secondary to age-related macular degeneration (AMD) and NE MNVs secondary to pachychoroid spectrum. Patients diagnosed with NE-MNV documented by OCTA and dye angiography in the context of either AMD or pachychoroid spectrum were retrospectively included in AMD group and PACHY group respectively. Only treatment-naïve NE MNVs showing persistence of non-exudative status for at least 1 year after diagnosis were considered. Availability of good quality structural OCT B scan and IR enface acquisitions both at baseline and at 1 year follow up was also required. The study population included 15 eyes of 15 patients in AMD group and 13 eyes of 13 patients in PACHY group. AMD group showed at baseline a significantly wider pigment epithelium detachment (PED) apex angle (p = 0.02), higher homogeneity of the PED (p = 0.015), higher PED shadowing(p = 0.03). Both groups experienced a widening of apex angle (flattening of the PED) during follow-up. Ten (76.9%) patients in PACHY group showed a hyporeflective halo at the margins of the PED at baseline compared to 3/15 (20.0%) patients in AMD group (0.007), with no significant changes at 1 year follow up (p = 0.47). NE-MNVs in pachychoroid eyes are characterized by sharper and more inhomogeneous PEDs with a lighter choroidal shadowing compared to NE-MNVs in AMD eyes. Moreover, they often show a hyporeflective halo around the lesion with IR imaging.