What does injected conjunctiva mean

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The Conjunctiva (Conjunctiva) is a type of mucous membrane that covers the inside of the eyelids and connects them to the eyeball. It extends from the edge of the eyelid to the cornea. The conjunctiva is well supplied with blood and very sensitive to external stimuli. Read everything you need to know about the conjunctiva!

What is the conjunctiva

The conjunctiva (conjunctiva) is a mucous membrane-like layer of tissue that connects the eyeball (Bulbus oculi) with the eyelids. It is well supplied with blood, transparent, moist, smooth and shiny. The conjunctiva is firmly fused in the area of ​​the eyelid. It rests a little looser on the eyeball. The conjunctiva covers the dermis (sclera) up to the edge of the cornea. There is no conjunctiva in the area of ​​the cornea that covers the iris and pupil, otherwise the cornea would be cloudy.

The conjunctiva is very sensitive to external stimuli.

The three sections of the conjunctiva

The conjunctiva (conjunctiva) consists of three sections:

  • Eyelid conjunctiva: It covers the inside of the eyelids. Medical term: conjunctiva tarsi or tunica conjunctiva palpebrarum.
  • Conjunctiva: It covers the front, visible part of the eyeball. Medical term: conjunctiva bulbi or tunica conjunctiva bulbi.
  • upper and lower conjunctival sacs: These two folds form the transition between the eyelid and the conjunctiva. The medical term for the conjunctival sac is Saccus conjunctivalis.

The structure of the conjunctiva

The conjunctiva consists of several layers of cells. In this non-keratinized squamous epithelium Occasional mucus-forming goblet cells and additional lacrimal glands are embedded. The secretion of the conjunctiva is used to moisten the eye and is an important part of the tear film.

Below is - from one Basement membrane separated - one Layer of loose connective tissue (Lamina propria; subconjunctiva). It is criss-crossed by many fine blood vessels.

The conjunctival blood vessels are usually invisible. If the eye is irritated, they will be filled with more blood (conjunctival injection) - the eye will turn red.

The conjunctiva is firm and immovable with the Eyelid cartilage (Tarsus palpebrae), a crescent-shaped flexible connective tissue plate in the upper and lower eyelids, which gives the lids a little firmness.

In the area of ​​the inner corner of the eye a small curved one Mucosal fold (Plica semilunaris conjunctivae). This is a rudimentary remnant of the well-mobile nictitating membrane still preserved in animals, which is also known as the "third eyelid".

The conjunctiva is easy to move in the area of ​​the white dermis. In the area of ​​the edge of the cornea, it is firmly attached to the subsurface again and merges into the corneal epithelium.

On the back surface of the eyelids, the conjunctiva has follicles with plasma cells and lymphocytes, which represent a barrier for pathogens and are involved in the immune response.

Sensitive and resorbable

Because the conjunctiva is heavily pervaded by sensitive nerves, it reacts accordingly sensitively to stimuli, foreign bodies or the like. In addition, it is very absorbent, which is why many drugs for the eyes are instilled into the conjunctival sac.

What problems can the conjunctiva cause?

Various ailments and diseases can occur in the conjunctival area.

acid burns

Accidents involving strong acids, alkalis or other chemicals can cause burns to the conjunctiva and cornea. In the worst case, the affected eye loses its vision.

Rapid action is necessary in the event of burns to the eyes! Always alert the emergency services in the event of accidents involving chemicals.

Inflammation of the conjunctiva

Conjunctivitis (conjunctivitis) can be recognized by a "red" eye, a foreign body sensation in the eye and a watery, slimy or even purulent secretion. The possible triggers of inflammation are many:

Often stuck Pathogens (such as bacteria, viruses, fungi) behind conjunctivitis.

In other cases, the inflammation is the result of a allergy: So-called rhinoconjunctivitis can develop in the context of house dust allergy, animal hair allergy or hay fever. This is a combination of an inflammation of the nasal mucous membrane (with a runny or blocked nose) and an inflammation of the conjunctiva.

Very often conjunctivitis is also caused by unspecific stimuli triggered. These include, for example:

  • smoke
  • dust
  • heat
  • cold
  • wind
  • UV light
  • Eye strain, e.g. due to long work at the PC, exhaustion, lack of sleep or incorrectly correcting glasses
  • Misalignment of the eyelids: ectropion (turning an eyelid outward) and entropion (turning an eyelid inward)
  • Trichiasis: Inward turning of the eyelashes without entropion - the eyelashes rub against the conjunctiva, which can become inflamed

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