Eyelids Flashcards
(166 cards)
Belpharospasm
squinting
Blepharitis
swelling of the eyelids
lagophthalmos
inability or incomplete blinking
where the upper and lower lids meet (nasal and lateral)
canthus
blinking upon stimulation of the face, particularly near the canthi
palpebral reflex
the region under the eyelid where the palpebral conjuctiva lines eyelid bends back to become bulbar conjunctiva (where foreign bodies get trapped)
fornix
excessive tearing
epiphora
Why might a patient have Lagophthalmos
1) Exophthalmos - physically cant get lid over eyelid
2) Nerve problems (ex: Facial nerve VI)
It can numb the eye during an eye surgery or procedure
Proparacaine
Epiphora
excessive tearing
swelling of eyelids
Blepharitis
What are the functions of eyelids
1) General ocular protection
2) Spread tear film, prevent evaporation
3) Clean debris from the eye and push tears down the nasolacrimal duct
4) Produce portions of tear film
What makes the lipid component of the tear film
meibomian glands
What makes the mucin component of tear film
conjunctiva
What makes the aqueous portion of the tears
lacrimal gland
70% lacrimal gland (above globe)
30% gland of the third eyelid
How much of the eyelid can you remove
remove up to 1/3 of the eyelid without having to perform specialized flap/ grafting surgery
upper lid form and function is more vital than the lower
Is the function of the upper lid or lower lid more vital
Upper lid (need to get good apposition during surgery)
lower lid, dont necessarily need to get perfect apposition
controls the muscles to the face, allows us to blink
provies parasympathetic stimulation of the lacrimal glands
CN VII
Facial Nerve Paralysis Clinical signs
1) patients will have lagophthalmos (absent palpebral reflex and menace) but intact facial sensation
-may learn to blink with Abducens (VI)
2) some may have keratoconjunctivitis sicca (neurogenic dry eye)
3) Drooping of face on affected side
How can a patient have facial nerve paralysis with normal tear production
depends on where the lesion is
parasympathetic branch of VII breaks off early and runs with CN V for majority of pathway
similarly, you can have neurogenic KCS with an intact palpebral
Patients with facial nerve paralysis may learn to blink with ___________
Abducens (CN VI)
T/F: you can see lagophthalmos without neurogenic dry eye (keratoconjunctivitis sicca)
True- parasympathetic branch of VII breaks off early and runs with CN V for majority of pathway
T/F: you can see neurogenic dry eye without lagopthalmos
true- just damage to the parasympathetic branch of CN VII - breaks off early
What test would you to do rule out neurogenic dry eye
Schirmer tear test