INCREASED LIPID PEROXIDE LEVEL AND MYELOPEROXIDASE ACTIVITY IN THE VITREOUS OF PATIENTS SUFFERING FROM PROLIFERATIVE VITREORETINOPATHY

Background: Retinal pigment epithelium cells and activated phagocytes are believed to be involved in the pathogenesis of proliferative vitre oretinopathy (PVR). Both cell types are capable of producing oxygen fr ee radicals and other molecules with a high oxidative potential which can lead to a propagation of oxidative damage. It was the aim of this study to investigate whether products of oxidative reactions are detec table in the vitreous body of patients suffering from PVR. Methods: In vitreous aspirates of patients vitrectomized because of PVR (n = 27), macular pucker (n = 9), or other reasons (controls, n = 31), the foll owing parameters were determined: lipid peroxides (LPO), determined as malondialdehyde-like substances (MDA) and as thiobarbituric acid-reac tive substances (TBARS), and myeloperoxidase activity (MPO). Results: Compared with the controls, both LPO levels and MPO activities were si gnificantly elevated in the vitreous of patients suffering from PVR. V itreous of patients with macular pucker did not reveal any significant differences from controls in the parameters analyzed. Conclusion: Our results suggest that both oxygen free radicals and inflammation-relat ed reactions participate in the process of PVR. Oxidative tissue damag e is obviously not involved in the pathogenesis of macular pucker.