Aqueous Humor Cytokines in Patients With Acute Nonarteritic Anterior Ischemic Optic Neuropathy

Abstract

To measure and compare the cytokine concentrations in the aqueous humor of patients with acute nonarteritic anterior ischemic optic neuropathy (NAION) and normal age-related cataract controls. Prospective, comparative observational study. Aqueous humor samples were obtained in 10 patients with acute NAION (within 14days of symptom onset) and 15 control patients with age-related cataract. The levels of 6 cytokines-vascular endothelial growth factor (VEGF), tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-2, IL-6, and IL-8-were determined using a multiplex bead immunoassay. The clinical characteristics of patients were also collected for correlation analysis. The mean concentration of VEGF (94.1 ± 40.4 pg/mL) was significantly higher in the NAION group compared to the cataract controls (52.2 ± 20.8 pg/mL; P= .010) and the mean concentration of IL-2 (5.56 ± 1.27 pg/mL) was significantly lower in the NAION group than in the cataract controls (16.6 ± 14.0 pg/mL; P= .002). There were no differences in the concentration of TNF-α, IL-1β, IL-6, and IL-8. There was a strong negative correlation between the VEGF concentration and the peripapillary retinal nerve fiber layer (RNFL) thickness at presentation (r=-0.657, P= .055). There was no significant correlation between the RNFL thickness and any other cytokines, the mean deviation on 24-2 Humphrey visual fields, or the duration of vision loss. Acute NAION is associated with higher VEGF and lower IL-2 concentrations without a change in other inflammatory cytokines. This has implications for future therapeutic interventions and diagnostic testing in patients with this acute optic neuropathy.