Evaluation of iron, zinc, and copper levels in pterygium tissue

Abstract

To determine the concentration of the trace elements iron, copper, and zinc in pterygium tissue and healthy conjunctiva tissue and to investigate the involvement of these elements in pterygium etiopathogenesis. Twenty patients with pterygium were enrolled in the study. The pterygium was excised and a conjunctival rotational flap or autograft inserted. Normal conjunctiva tissue was obtained from the flap or graft. The concentrations of iron, zinc, and copper in the pterygium and conjunctiva tissues were determined by atomic absorption spectrometry after microwave digestion. Iron, zinc, and copper levels were significantly higher in the pterygium tissue than in the normal conjunctiva (P < 0.001). The mean iron, zinc, and copper concentrations in the pterygium tissue were 819, 214, and 3.40 μg/g, whereas the mean concentrations of these elements in the control tissue were 491, 148, and 2.19 μg/g, respectively. Pterygium is a fibrovascular proliferative disorder and elevated levels of trace elements in pterygium tissue may play a pathogenic role via oxidative damage.