More (Latin palpebrae ) cover the eye from the front and thus protect it.
Both the upper and lower eyelids are built almost the same, and consist of several layers. Looking from the outside in, these are the skin, the muscle layer, the connective layer (tarsus) and the joint. They also contain a large number of sebaceous and sweat glands (Meibomian, Zeiss and Moll’s), whereby the sebaceous glands play a role in “lubricating” the eye, i.e. together with the lacrimal glands that secrete tears, they enable the eyelids to slide over the eyeball more easily.
Blinking the eyelids is a reflex action. We normally blink about 10-20 times a minute and in this way we distribute the tears produced in the lacrimal gland throughout the eye. Frequent blinking can be caused by the sensation of a foreign body in the eye or a polluted atmosphere (eg cigarette smoke). We reflexively close our eyelids when touching the eyelashes or the eyeball itself, when illuminated by bright light or when an object suddenly approaches the eye. We can also close the eye with willpower.
Eyelid muscles:
- 1. M. Orbicularis oculi
- He closes his eyelids
- Innervates n. Facialis (7th cranial nerve)
- 2. M. Levator palpebrae
- Upper eyelid lifter
- Innervates n. Oculmotorius (3rd cranial nerve)
- 3. M. Tarsalis
- Determines the width of the usual gap
Eyelid position disorders
Ectropium ( ectropium )
Ectropium is a change in the position of the edge of the eyelid that is turned outward
Entropy (entropium )
Entropy is an inward turning of the eyelid.
ptosis
With ptosis, we are talking about an abnormally low position of the upper eyelid. At the same time, the eyelid can be more or less mobile.
Eyelid retraction ( retractio palpebrarum )
Contrary to ptosis, retraction of the upper eyelid refers to its pulling upwards.
Blepharochalasis ( blepharochalasis )
Blepharochalasis is a condition characterized by occasional swelling of the upper eyelid, causing the skin to stretch over time. This creates a relative excess of skin that overlaps and looks unaesthetic. Treatment is operative.
Autor:
bc. Livio Svržnjak, optometrist
Literature:
M.Sc. sc. Pavan Dr. Joško, “Eye Diseases”, Zagreb 2003.
