Adenexa and Anatomy of Eyelid Flashcards
(24 cards)
What muscles move the eyebrows?
Frontalis, corrugator, procerus, orbicularis
What effect does frontalis have on the eyebrow?
Elevation (as in surprise)
What effect does corrugator have on the eyebrow?
Pulls medial sides of eyebrows together (as in concentration)
What effect does procerus have on the eyebrow?
Pulls medial eyebrow down and medially (as in agression)
What effect does orbicularis have on the eyebrow?
Lowers eyebrow
The palpebral sulci divide each eyelid into what two portions?
Orbital portion (from sulcus to brow or cheek); tarsal portion (from sulcus to lid margin)
What is the plica semiluminaris, and what is its function?
A fold of conjunctiva at the medial canthus that allows for lateral globe movement without stretching the conjunctiva. It also forms the floor of the lacrimal lake.
Define caruncle
A mass of modified skin at the medial canthus; it forms the medial wall of the lacrimal lake.
Name the muscles of the eyelid
Orbicularis oculi, superior palpebral levator, superior tarsal muscle (of Muller), inferior tarsal muscle (of Muller)
What is the action of the orbital portion of the orbicularis oculi?
A sphincter-type contraction (runs from medial palpebral ligament to medial palpebral ligament)
Into what two muscles is the palpebral portion of the orbicularis oculi divided?
Horner’s muscle (around lacrimal canalliculi for tear drainage); Riolan’s muscle (along lid margin to adhere lid to globe)
What is the origin of the superior palpebral levator?
Lesser wing of sphenoid
What is the insertion of the superior palpebral levator?
Tarsal plate and dermis of eyelid
What is the aponeurosis?
A fan-shaped tendon of insertion of the superior palpebral levator
Name the two portions of the aponeurosis.
Medial horn and lateral horn (the lateral horn divides the lacrimal gland into an orbital portion and a palpebral portion)
What is the origin of the superior tarsal muscle?
Levator
What is the insertion of the superior tarsal muscle?
Superior tarsal plate
What is the origin of the inferior tarsal muscle?
Sheath of inferior rectus
What is the insertion of the inferior tarsal muscle?
Lower tarsal plate or CT of eyelid
What is the action of the orbicularis oculi?
Spontaneous blinking (palpebral portion); forceful blinking (orbital portion)
What is an epicanthus?
A fold of lid tissue that “hides” the medial canthus; can give the appearance of esotropia.
What is an ectropion?
A turned-out lid margin
What is an entropion?
A turned-in lid margin
What is blepharospasm?
Forced, involuntary closure of the lids
