export_eyelids Flashcards
- lines surfaces of bones of orbit
- continuous with periosteum of face
Periorbita
Frontalis
origin:
insertion:
innervation:
action:
scalp
superior orbital rim
VII (temporal branch)
raise the eyebrow, look of surprise
Corrugator supercili
Origin:
Insertion:
Innervation:
Action:
Frontal bone
Skin superior to the medial eyebrow
VII (temporal branch)
moves brow medially, look of concentration
Procerus
Origin:
Insertion:
Innervation:
Action:
nasal bone
medial side of frontalis
VII (buccal branch)
pulls the medial brow inferiorly, look of menace
Obicularis Occuli
Origin:
Innervation:
medial bony orbit
VII (temporal and zygomatic branch)
Eyelids/ palpebrae
Functions:
- cover the globe for protection
- move the tears
- spread the tears
- produce tear film
- protect from UV and sweat
Lagophthalmos:
- can result in keratitis, improper tear drainage, corneal ulceration
incomplete closure of the eyelids
Space between open eyelids
Palpebral Fissure
the inner and outer angles that are formed by the meeting of the upper and lower eyelids
Canthus: medial and lateral
Lacrimal papilla
- small elevation on lid margin
contains:
divides lid margin into:
puncta
lateral ciliary portion and nasal lacrimal portion
Epicanthus
covers:
found in:
caruncle and plica semilunaris
young children of all races, children with developmental problems, and adults of Asian descent
loss of eyelashes
madarosis
whitening of the cilia (usually because of age)
poliosis
misdirected growth of eyelashes
trichiasis
spasmodic contraction of the obicularis
blepharospasm
Orbital portion of Obicularis Oculi
Origin/Insertion:
Action:
Opposing muscle:
medial bony orbit
closes eye tightly and quickly/reflex
frontalis
Palpebral portion
origin:
insertion:
action:
opposing:
medial palpebral ligament
half-ellipses in lateral palpebral raphe
closure of eye gently; involuntary blinking
levator
Horner’s muscle
origin:
action:
lacrimal sac from upper posterior lacrimal crest
compresses canliculi
Riolan’s muscle
location:
action:
near lid margin posterior to cilia on both sides of meibomian pores
holds lid margin in close contact with globe
Levator palpebrea
Origin:
Insertion:
Innervation:
Action:
O: lesser wing of sphenoid bone above and anterior to optic foramen. Levator sheath attaches to the sheath of the superior rectus muscle> for coordination of movement (so when you look up with superior rectus, your eyelid opens more)
I: fibres pass between bundles of orbicularis to insert onto the skin and tarsus.
I: CN III (superior division of oculomotor)
A: elevates eyelids
Superior palpebral levator divides the lacrimal gland into two lobes:
orbital and palpebral
Levator has expansions called horns.What is the function of the horns? How are the medial and lateral horns different?
Function: provide a firm anchor point for levator to pull off of and give support to lacrimal gland.
Lateral horn: thicker, more firmly attached (pass by lacrimal gland, so must be strong and give it support)
Action, origin, insertion and inervation of Muller’s muscle
Action: Additional lid elevation, widen palpebral fissure; Origin: levator; Insertion: upper border of tarsal plate; (hugs inside aspect of levator) Innervation: SNS
Inferior tarsal muscle
origin:
insertion:
innervation:
action:
O: inferior rectus muscle sheath
I: lower conjunctiva and inferior border of lower tarsal plate
I: sympathetic
A: lowers lower lid, widens palpebral fissure
