Konjunktiva

Konjunktiva, or conjunctiva, is a thin, transparent mucous membrane that lines the inside of the eyelids (palpebral conjunctiva) and covers the anterior surface of the sclera (bulbar conjunctiva). It extends over the upper and lower fornices, forming the conjunctival sac at the medial and lateral canthi. The epithelium is non-keratinized stratified squamous with goblet cells that secrete mucins, supported by a loose connective tissue stroma rich in blood vessels and immune cells.

Functions include lubrication of the ocular surface through the tear film, protection against pathogens, and contribution to tear-film stability and immune surveillance via conjunctival-associated lymphoid tissue. The conjunctiva helps maintain a barrier between the external environment and intraocular tissues and plays a role in tear distribution.

Clinically, the conjunctiva is commonly affected by inflammation (conjunctivitis) of various etiologies: allergic, bacterial, or viral. Other conditions include pterygium, a fibrovascular growth from the bulbar conjunctiva onto the cornea, and pinguecula, a yellowish degeneration on the bulbar surface near the cornea. On examination, signs include conjunctival injection (redness) and, depending on the cause, follicles or papillae, as well as localized lesions.

The conjunctiva is supplied by branches of the ophthalmic artery and innervated by sensory fibers of the ophthalmic division of the trigeminal nerve. It works with the lacrimal system to maintain a healthy ocular surface.