Conjunctiva

The conjunctiva (Latin tunica conjunctiva, which also Germanized conjunctiva ) is a mucous membrane in the orbit ( eye socket) in the anterior segment of the eye.

Anatomy

It begins at the edge of the eyelid and covers the tunica conjunctiva palpebrarum the rear, the eyeball facing surface of the eyelids. This mucous coating acts like a soft cloth and distributed during blinking the tears over the cornea ( cornea) without hurting them. In the depth of the orbit, the conjunctiva strikes again to move forward and connects to the sclera. The conjunctiva covering the front portion of the sclera to the beginning of the cornea, this portion is referred to as the tunica conjunctiva bulbi.

The enveloped by the conjunctival cavity is the conjunctival sac ( conjunctival sac ). Its rear niche in the depth of the eye socket is called the conjunctiva vault ( conjunctival fornix ). Here open the excretory ducts of the lacrimal gland ( lacrimal gland ). The tear fluid at the nose-side canthus two puncta ( puncta lacrimalia ) derived towards the nose.

The conjunctiva is the nasal canthus an additional fold, which is called the nictitating membrane ( plica semilunaris conjunctivae, membrane nicitans ) or third eyelid ( palpebra tertia ). It is only very small in humans. In the other mammals it is so big that they can put in front of the entire eye. In many other vertebrates, such as sharks, reptiles and birds, it is transparent and can be folded as safety glasses to his eyes.

In the mucosa of the conjunctiva individual glands packets are stored to be referred to as the accessory lacrimal glands. On the nose-side angle of the eye, the conjunctiva to Tränenkarunkel ( lacrimal caruncle ) is thickened.

The terminal branches of the blood vessels in the conjunctiva at the transition region of the sclera and cornea are called edge loop network. This participates in the supply of the avascular cornea. If there is inflammation of the cornea can one sprout into the cornea from this edge loop network of blood vessels.

Clinical Significance

The conjunctiva is considered at every general clinical examination. Since it is quite thin, well perfused and unpigmented, changes of the blood can be captured well. Thus one sees a yellow coloration when icterus ( jaundice), and pallor with anemia or shock.

Inflammation of the conjunctiva are known as conjunctivitis. It occurs in local irritation (eg, foreign body ) and infections or even in the wake of some common infectious diseases (eg, measles, distemper ) on. Solitary follicles in the conjunctiva can zoom in inflammation strongly and then act like sandpaper and can injure the cornea.

A sub- conjunctival haemorrhage is also called Hyposphagma, but it does not cause discomfort.

In a pushing or sinking of the eyeball ( enophthalmos, such as muscle spasms such as tetanus ) occurs in animals at a nictitating membrane.