Therefore our aim was to determine and to compare the concentrations of various mediators (IL-6, -10, CCL5/RANTES, CXCL8/IL-8, chemokine (C-X-C motif) ligand (CXCL10)/interferon-gamma-inducible protein 10 (IP-10), MMP-9, -13, TIMP-1, tissue plasminogen activator (t-PA), plasminogen activator inhibitor (PAI-1) and NGF) in the tear film of patients with PMD and KC in order to reveal any possible biochemical differences between these two entities. This evidence concerns the gene TIMP1 and keratoconus.