Relationship between the Presence of a Cilioretinal Artery and Subretinal Fluid in Neovascular Age-Related Macular Degeneration

Abstract

Purpose: To evaluate the relationship between presence of a cilioretinal artery (CRA) and the extent of subretinal fluid (SRF) in eyes with treatment-naïve neovascular age-related macular degeneration (nAMD). Eyes with nAMD have varying amounts of SRF, and factors affecting exudation volume are not well established. We hypothesize that presence of CRA may affect the extent of SRF by affecting the hemodynamics of blood flow supplying the choroidal neovascular membrane.

Design: Retrospective case-control study.

Participants: Two hundred twelve patients with treatment-naïve nAMD in at least 1 eye from anonymized datasets available at the Doheny Image Reading Center.

Methods: Color fundus photographs and fluorescein angiograms of the study eyes were reviewed to identify those with a CRA (cases) and those without (controls). Spectral-domain OCT data were evaluated by 2 masked graders to identify presence and volume of SRF. We identified subtypes of CNV and evaluated other OCT features that could affect SRF, such as presence of subretinal hyperreflective material (SHRM), cystoid macular edema (CME), and pigment epithelial detachment (PED). Nonparametric Mann-Whitney U test and univariate and multivariate analyses were performed to identify significant differences between cases and controls and to evaluate the relationship between these factors and SRF volume.

Main outcome measures: Presence and volume of SRF, presence of CME, PED types, and CNV types.

Results: We identified 44 cases and 168 controls. Mean SRF volume was significantly lower in cases than controls (0.72±0.9 mm³ vs. 1.60±2.36 mm³; P = 0.03). Univariate regression analysis showed a weakly significant correlation between presence of CRA and SRF volume (r = -0.15; P = 0.03) and OCT parameters, including SHRM (r = 0.16; P = 0.023), CME (r = -0.20; P = 0.004), and type 2 CNV (r = 0.16; P = 0.02). Multivariate analysis demonstrated that the presence of a CRA (r = -0.17; P = 0.02) was correlated independently with the presence of SRF.

Conclusions: Presence of a CRA was correlated negatively with the volume of SRF in eyes with nAMD. These findings may draw insights into the potential hemodynamic effect of the CRA, which warrants further investigation.