Conjunctiva
From WikiMD's WELLNESSPEDIA
Conjunctiva[edit]
The conjunctiva is a thin, transparent mucous membrane that covers the sclera (the white part of the eye) and lines the inside of the eyelids. It plays a crucial role in maintaining the health of the eye by providing a protective barrier against environmental irritants and pathogens.
Anatomy[edit]
The conjunctiva is divided into three parts:
- Palpebral conjunctiva: This part lines the inside of the eyelids. It is highly vascularized and adheres tightly to the tarsal plates of the eyelids.
- Bulbar conjunctiva: This part covers the anterior surface of the sclera, up to the cornea. It is loosely attached to the underlying tissue, allowing for free movement of the eyeball.
- Fornix conjunctiva: This is the loose, flexible fold that connects the palpebral and bulbar conjunctiva, allowing for the movement of the eye and eyelids.
Function[edit]
The primary functions of the conjunctiva include:
- Protection: It acts as a barrier to dust, debris, and microorganisms, preventing them from entering the eye.
- Lubrication: The conjunctiva produces mucus and tears, which help to keep the eye moist and facilitate smooth movement of the eyelids over the eyeball.
- Immune defense: It contains immune cells that help to detect and respond to pathogens.
Clinical Significance[edit]
The conjunctiva can be affected by various conditions, including:
- Conjunctivitis: Also known as "pink eye," this is an inflammation of the conjunctiva, often caused by infections, allergies, or irritants.
- Pterygium: A benign growth of the conjunctiva that can extend onto the cornea, potentially affecting vision.
- Pinguecula: A yellowish, benign growth on the conjunctiva, usually on the side closest to the nose.
Histology[edit]
The conjunctiva is composed of a non-keratinized stratified columnar epithelium with goblet cells interspersed throughout. These goblet cells are responsible for secreting mucus, which contributes to the tear film and helps maintain ocular surface health.
