The purpose of this study was to research lymphatic outflow tract in the human choroid. Using a light microscopy and immunohistochemistry, structure of the choroid was investigated. We used antibodies against lymphaticendotheli-al-specificmarkers Prox-1, LYVE-1, Podoplanin, endothelial blood vessels marker CD34 and fibroblasts growth factor receptor FGFR. The choroid was found to contain lymphatic canals in choroidal stroma and a layer of choriocapillaris, and lymphatic lacunae in the suprachoroid lamina, limited endothelium-like cells, positively stained for markers of lymphatic vessels Prox-1, LYVE-1, Podoplanin, and fibroblasts and pigment cells. These endothelium-like cells were shown positive Prox-1, LYVE-1 and Podoplanin staining and negative CD34 staining; therefore we consider that these canals and lacunae are lymphatic structures.
choroid, lymphatic lacunae, lymphatic channel
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