Comparison of subfoveal choroidal structures in typical neovascular age-related macular degeneration and polypoidal choroidal vasculopathy

Abstract

Purpose: To evaluate and compare the intrachoroidal structures of eyes with typical neovascular age-related macular degeneration (AMD) with those of eyes with polypoidal choroidal vasculopathy (PCV).

Study design: Retrospective and comparative case series.

Methods: Eighty-four treatment-naïve eyes of 84 patients (22 women and 62 men) with typical neovascular AMD or PCV located in the subfoveal region were studied. Cross-sectional images of the retina and choroid were obtained by swept-source optical coherence tomography (SS-OCT). The horizontal SS-OCT images were analyzed by a manual delineation technique and by a binarization method.

Results: Thirty-nine eyes with typical neovascular AMD and 45 eyes with PCV were studied. Although the subfoveal choroidal thickness (SCT) did not differ significantly between the 2 subtypes (255.1 ± 86.7 µm in typical neovascular AMD and 289.2 ± 116.5 µm in PCV, P = 0.29), the ratio of the large choroidal vessel layer (LCVL) thickness to the SCT was significantly larger in the eyes with PCV than in the eyes with typical neovascular AMD (0.863 ± 0.084 vs 0.803 ± 0.125, P = 0.023). The binarization method did not find significant differences in the choroidal structure between the 2 subtypes. Multivariate logistic regression analyses found the ratio of the LCVL thickness to the SCT to be the only significantly different factor between typical neovascular AMD and PCV (P = 0.035).

Conclusion: The intrachoroidal structures of typical neovascular AMD and PCV eyes differ significantly. In eyes with PCV, there seemed to be a greater dilation of the large choroidal vessels.

Keywords: Age-related macular degeneration; Choroidal structure; Choroidal vasculopathy; Optical coherence tomography; Polypoidal choroidal thickness.