Conjunctival

Conjunctival refers to the conjunctiva, the thin mucous membrane that covers the anterior surface of the sclera (the white of the eye) and lines the inner surfaces of the eyelids. It forms two regions: the bulbar conjunctiva over the globe and the palpebral conjunctiva lining the eyelids, meeting at the fornices to create the conjunctival sac. The conjunctiva serves as a protective barrier against mechanical and microbial injury and contributes to tear film maintenance.

Histology and structure: The conjunctiva consists of non-keratinized stratified squamous epithelium with goblet cells, over a loose connective tissue stroma (lamina propria). The epithelium is thicker in the palpebral portion. The tissue contains vascular and lymphatic networks and immune cells; conjunctiva-associated lymphoid tissue provides local immune defense. Goblet cells secrete mucins that contribute to the mucous layer of the tear film, aiding lubrication and surface wetting.

Function: In addition to forming a barrier, the conjunctiva participates in immune surveillance and tear film stability. Goblet cell secretion helps maintain lubrication, while the epithelium and underlying tissue help protect the ocular surface from pathogens and irritants.

Clinical relevance: Common conditions include conjunctivitis (bacterial, viral, allergic), pinguecula and pterygium (degenerative growths on the conjunctiva), and conjunctival neoplasms (such as melanocytic lesions or squamous cell carcinoma). Diagnostic evaluation typically involves slit-lamp examination; impression cytology or biopsy may be used for abnormal or suspected dysplastic or neoplastic changes.