Angiogenesis in pterygium: histopathological and imunohistochemical study

Abstract

Pterygium is an active invasive inflammatory process, a key feature of which is focal limbal failure. It is a triangular conjunctival-epithelial overgrowth covering the cornea, a long term and recurrent illness that leads to permanent decrease of the visual acuity and esthetic changes of the eye’s anterior segment. Aim: The correlation between the stationary and progressive primary pterygium and recurrent pterygium was determined histo pathologically and immunohistochemically using the CD31 and CD34 antibodies for the identification of the vascular endothelium and micro density, i.e. angiogenesis in the pterygium tissue after pterygium excision with conjunctival autograft transplantation from the inferior bulbar conjunctiva. Material and methods: This study compares two groups of primary pterygium, stationary pterygium (30 patients) and progressive pterygium (30 patients), and one group of recurrent pterygium (30 patients), that were surgically treated with refractive surgical method of pterygium excision with conjunctival autograft transplantation from the inferior bulbar conjunctiva. In the period of 2009 to 2011, the surgeries were performed at the University Eye Clinic, while the histopathological and immuno histochemical study was performed at the Institute of Pathology using CD31 and CD34 antibodies for the angiogenesis identification. Results: No statistically significant difference was found in the vascular angiogenesis between the progressive and recurrent pterygium (Z=-0,258 p=0,7958), however statistically significant difference was found in the vascular angiogenesis between the stationary and either progressive (Z=-3,770 p=0,00016) or recurrent (Z=-3,866 p=0,00011) pterygium (using Mann-Whitney U Test). Conclusion: The higher developed angiogenesis in both primary progressive and recurrent pterygium, may support previous suggestions that angiogenesis may play a role in the formation of pterygia and its postoperative recurrence.