Abstract
Purpose: :
To identify the impact of antiangiogenic therapy on growth factors and inflammatory cytokines in eyes with branch (BRVO) and central retinal vein occlusion (CRVO).
Methods: :
In a prospective clinical trial, 13 eyes of patients with BRVO and CRVO were included. Bevacizumab was administered intravitreously at baseline, month 1 and 2. Re-treatments were given at monthly visits if OCT showed intra- or subretinal fluid, or at vision loss of at least 5 ETDRS letters. Aqueous humor samples were taken each time intravitreal injections were performed. Follow-up was 15 months. Samples from cataract patients served as control.Luminex multiplex assays were used for measurement of 28 growth factors and cytokines.
Results: :
Significant differences between patients with BRVO or CRVO and control patients were found in the concentration of IL-1b, IL-5, and Eotaxin. Concentrations of IL-1a, IL-10, IL-15, IL-6, IP-10, MCP-1, PDGF-AA, and VEGF varied between CRVO and control patients.Under anti-VEGF therapy, VEGF levels were significantly reduced. Mean values for BRVO were 125.9pg/ml at baseline, 0.01pg/ml at month 1 (p=0.02), 0.57 pg/ml at month 2 (p=0.01), and 0.68pg/ml at month 3 (p=0.02); for CRVO 904.65pg/ml at baseline, 75.17pg/ml at month 1 (p=0.04), 143.81pg/ml at month 2 (p=0.04), and 129.25pg/ml at month 3 (p=0.07).When criteria for re-treatment were met, VEGF levels were high again (e.g. 53.78 pg/ml in patients with BRVO at month 6; p=0.6). Changes of VEGF levels correlated with visual acuity and central retinal thickness (p<0.001).Other significantly reduced cytokines under therapy were IL-1a, IL-1b, IL-12p40, RANTES, and IP-10 in patients with BRVO, and PDGF-AA, IL-6, IP-10, and MCP-1 in patients with CRVO.
Conclusions: :
Intravitreal injections of Bevacizumab resulted in a substantial decrease of VEGF levels. This effect was measurable over a time period of four weeks after injection. VEGF levels remained low under consecutive monthly re-treatment and increased following discontinuation of therapy with recurrent edema.
Clinical Trial: :
EudraCT 2006-005684-26
Keywords: aqueous • vascular occlusion/vascular occlusive disease • drug toxicity/drug effects