Conjunctiva

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Conjunctiva
Gray883.png
The upper half of a sagittal section through the front of the eyeball. (Label for 'Conjunctiva' visible at center-left.)
Gray869.png
Horizontal section of the eyeball. (Conjunctiva labeled at upper left.)
Gray's subject #227 1026
Artery lacrimal artery, anterior ciliary arteries
Nerve supratrochlear nerve
MeSH Conjunctiva
Image of a human eye clearly showing the blood vessels of the conjunctiva.
Hyperemia of the superficial blood vessels of the conjunctiva.

The conjunctiva (plural conjunctivas or conjunctivae) is a clear mucous membrane consisting of cells and underlying basement membrane that covers the sclera (white part of the eye) and lines the inside of the eyelids. It is composed of rare stratified columnar epithelium.

Contents

[edit] Function

The conjunctiva helps lubricate the eye by producing mucus and tears, although a smaller volume of tears than the lacrimal gland.[1] It also contributes to immune surveillance and helps to prevent the entrance of microbes into the eye.

[edit] Gross anatomy

The conjunctiva is typically divided into three parts:

Part Area
Palpebral or tarsal conjunctiva lines the eyelids
Bulbar or ocular conjunctiva covers the eyeball, over the sclera. This region of the conjunctiva is tightly bound to the underlying sclera by Tenon's capsule and moves with the eyeball movements.
Fornix conjunctiva Forms the junction between the bulbar and palpebral conjunctivas. It is loose and flexible, allowing the free movement of the lids and eyeball. .[2]

[edit] Histology

The conjunctiva consists of nonkeratinized squamous epithelium.

[edit] Diseases and disorders

Disorders of the conjunctiva and cornea are a common source of eye complaints.

The surface of the eye is exposed to various external influences and is especially susceptible to trauma, infections, chemical irritation, allergic reactions and dryness.

The conjunctiva can become inflamed secondary to bacterial infection. The resultant condition is known as conjunctivitis and commonly referred to as pinkeye.

Conjunctival irritation can occur for a wide variety of reasons including dry eye and overexposure to VOCs (Volatile organic compounds).

With age, the conjunctiva can stretch and loosen from the underlying sclera, leading to the formation of conjunctival folds, a condition known as conjunctivochalasis.[3][4]

[edit] See also

[edit] Additional images

[edit] References

  1. ^ London Place Eye Center (2003). Conjunctivitis. Retrieved July 25, 2004.
  2. ^ Eye, human Encyclopaedia Britannica
  3. ^ http://www.medilexicon.com/medicaldictionary.php?t=19916
  4. ^ WL Hughes Conjunctivochalasis. American Journal of Ophthalmology 1942

[edit] External links


Personal tools
Namespaces
Variants
Actions
Navigation
Interaction
Toolbox
Print/export
Languages