Conjunctiva

Mucous membrane that covers the front of the eye and lines the inside of the eyelids

The conjunctiva is a thin, transparent mucous membrane that plays a crucial role in the protection and function of the eye. It covers the front part of the sclera and lines the inside of the eyelids.

Anatomy

The conjunctiva is divided into three parts:

• Palpebral conjunctiva: This part lines the inside of the eyelids. It is firmly attached to the tarsal plates and is highly vascularized.
• Bulbar conjunctiva: This portion covers the anterior part of the sclera and is loosely attached to the underlying tissue, allowing for free movement of the eyeball.
• Fornix conjunctiva: This is the junction between the palpebral and bulbar conjunctiva, forming a loose fold that allows for the movement of the eyeball and eyelids.

Function

The conjunctiva serves several important functions:

• Protection: It acts as a barrier against dust, microorganisms, and other foreign particles.
• 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 fight infections.

Clinical Significance

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.
• Subconjunctival hemorrhage: This occurs when a small blood vessel breaks under the conjunctiva, leading to a red patch on the white of the eye.
• Pterygium: A benign growth of the conjunctiva that can extend onto the cornea, potentially affecting vision.

Images

File:Conjunctiva diagram.png

Diagram of the conjunctiva showing its three parts: palpebral, bulbar, and fornix.

A case of conjunctivitis showing redness and swelling of the conjunctiva.

Related pages

• Eye
• Sclera
• Cornea
• Eyelid