Early effects of intravitreal triamcinolone acetonide on inflammation and proliferation in human choroidal neovascularization

Objective: To evaluate the early effects of triamcinolone acetonide (TA) on inflammation, proliferation, and vascular endothelial growth factor (VEGF) in human choroidal neovascularization (CNV). Methods: Retrospective review of an interventional case series of 29 patients who underwent macular translocation. Fourteen CNV membranes without previous therapy (control CNV group) and 4 CNV membranes excised 3 days after photodynamic therapy (PDT CNV group) comprised the control groups. Eleven patients were treated with intravitreal TA (TA CNV group; n=5) or PDT and TA combined (PDT+TA CNV group; n=6) 3 to 9 days preoperatively. The CNV membranes were stained for cytokeratin 18, CD34, VEGF, intercellular adhesion molecule-1 (ICAM-1), E-selectin, CD68, CD45, Ki-67, and Thy-1. Results: Treatment with TA and PDT+TA resulted in increased immunostaining of ICAM-1 in endothelial cells and the stroma and a higher percentage of Thy-1 expression than controls. The density of macrophages was significantly increased in PDT+TA CNV membranes. Leukocyte density and proliferative activity were lower in TA and PDT+TA CNV membranes. The total VEGF score was significantly increased in TA and PDT+TA CNV membranes compared with the control CNV membranes. Evidence of VEGF in the retinal pigment epithelium of PDT+TA CNV membranes was stronger than in control CNV membranes. Conclusions: Triamcinolone acetonide has no inhibitory effect on macrophage infiltration or ICAM-1, Thy-1, or VEGF expression in CNV membranes in the early term. The clinical benefits of TA are probably not based on pure antiinflammatory or VEGF-suppressing mechanisms.