Inflammatory cells and oxidative metabolites lead to oxidative reactions in PDR and PVR. The proliferation of membrane tissue may be enhanced through products of the lipoxygenase pathway, which is active in inflammatory cells and leads to oxidative tissue damage. Chemoattraction of leukocytes by oxidative metabolites renders the process self-progagating. Since patients suffering from MP have an intact vitreous body with an intact antioxidative system, this reaction occurs to a lesser degree, resulting in less membrane-growth activity. The cell-growth-enhancing properties of inflammatory cells should be further investigated in PDR and PVR with regard to new therapeutic interventions.