LIMBAL AUTOGRAFT IN RECURRENY PTERYGIUM

Abstract

Pertygium is a common ke1iocojunctival degernerative lesion in tropical and subtropical regions. Egypt i:; considered one of the areas in which pterygium is prevalent. The exact aetiology of the pteryf:ium is not known but many theories have been put down to explain the aetiology of the pterygium like the neoplastic theory, Ultra- Violet light theory and tear abnormality theory, immunological theory, mechanic:al theory and the hereditary theory. The Ultra- Violet light theory is the most accepted one because of the prcv;dctlcc .ur tile ptcrygiu111 i11 the tropical an.;as. ll occurs more to people who work outdoors rather than indoors. As regards the pathology of the pterygium the earliest changes occuring in the cornea are the appearance of small vesicles at the point where the corneal nerves pierce Bowman's membrane. At these points Bowman's membrane becomes destroyed and the superficial corneal lamellae degenerate. The developed pterygium is covered by conjunctival epithelium. Clinically the pterygium appears :1s a triangular fleshy growth encroaching onto the cornea. The apex lying on the cornea called the he; cl, the bmly present . over the sclera, the neck is that part lying on the limbus behind the head. A pterygium does not give rise to symptoms if it is small. It may affect the vision if it progesses onto the: puillary area of the cornea or causes diplopia if it is large due to limitation of abduction from traction on the conjunctiva.