A comparative study of type 1 neovascularization: Neovascular age-related macular degeneration versus pachychoroid neovasculopathy

Abstract

Purpose: This study aimed to compare type 1 choroidal neovascularization (CNV) characteristics in eyes with pachychoroid neovasculopathy (PNV) and neovascular age-related macular degeneration (nAMD) using optical coherence tomography angiography (OCTA).

Methods: Treatment naive 23 eyes of 23 patients with PNV and 24 eyes of 24 patients with nAMD were evaluated. The height of pigment epithelial detachment (PED) and the central macular thickness were determined. OCTA sensitivity, CNV area, morphological patterns, and retinal superficial capillary plexus vessel density (SCP-VD) values were compared. The frequency of quiescent CNV, subretinal hyperreflective exudation (SHE), subretinal/intraretinal fluid, serous PED, double-layer sign (DLS), and pachyvessels were noted.

Results: CNV was detected on OCTA in 83.3% of nAMD eyes and 91.3% of PNV eyes (p = 0.66). Indistinct pattern was more common (74% vs 50%) and the CNV area (mm²) was smaller in PNV (0.77 ± 0.54 vs 1.57 ± 1.43) but did not reach significant levels (p = 0.27 and 0.33 respectively). SCP-VD was similar between the groups (p = 0.38). Statistically significant differences were found between groups in age and subfoveal choroidal thickness (p < 0.05). DLS and pachyvessels were found to be more frequently in PNV (p < 0.05). However, both groups had similar rates of quiescent CNV, SHE, subretinal/intraretinal fluid, and serous PED (p > 0.05).

Conclusion: Morphological features, area, and activation findings of type 1 CNV may play a limited role in differentiating nAMD and PNV cases.

Keywords: Choroidal neovascularization; neovascular age-related macular degeneration; optical coherence tomography angiography; pachychoroid neovasculopathy; quiescent neovascularization.