The effect of previous surgery and topical eye drops for primary open-angle glaucoma on cytokine expression in aqueous humor.

PURPOSE: To evaluate cytokine expression in the aqueous humor of patients with primary open-angle glaucoma (POAG) after previous glaucomatous and/or cataract surgery, and to determine the effect of intraocular pressure (IOP)-lowering eye drops on cytokine expression.

METHODS: This prospective consecutive case study included 32 eyes diagnosed with POAG (19 with previous surgery and 13 without previous surgery, treated with topical antiglaucoma medication) and 12 eyes without signs of glaucoma. The Luminex 200 multiplex bead immunoassay was used to measure 27 cytokines in aqueous humor.

RESULTS: Eyes suffering from POAG, with previous surgery, had significantly elevated concentrations of IL-6, IL-8, CCL2, CXCL9, and HGF, and a significantly lower concentration of CCL5, compared to POAG eyes without previous surgery, treated only with topical antiglaucoma medication. When compared with cataract controls, eyes with POAG and previous surgery had significantly elevated levels of G-CSF, IL-8, IL-12, CXCL10, and HGF, and significantly decreased concentrations of IL-17, CCL5, and VEGF in aqueous humor. In a comparison between POAG eyes without previous surgery and cataract controls, the cataract control eyes had significantly higher levels of IL-6 and CCL2, as the only significant difference.

CONCLUSIONS: POAG is associated with an aqueous inflammatory response in the aqueous humor, which is significantly elevated in eyes with previous surgery. In contrast, preoperative IOP-lowering eye drops did not significantly alter the anterior chamber milieu. The results of the current study indicate that filtration surgery has a higher success rate in eyes that have not experienced previous surgery.