Final Exam - Eyelids & 3rd Eyelids Flashcards
what is an aphakic crescent?
crescent shaped lesion that verifies lens subluxation
what is buphthalamos?
globe enlargement secondary to glaucoma
what is band keratopathy?
corneal degeneration that forms in a a band shape roughly matching the shape of the palpebral fissure that is often associated with lagophthalmos but can occur independent of exposure
what is blepharospasm?
spasm of the orbicularis oculi muscle resulting in eyelid closure (squinting)
what are cilia?
eyelashes
what is trichiasis?
normal cilia that are directed toward the cornea
what are distichia?
eyelashes emerging from the meibomian glands
what are ectopic cilia?
cilia growing from the palpebral conjunctiva
what is ectropion?
outward rolling of the eyelids that make animals often develop exposure keratitis or conjunctivitis due to the poor ability of the eyelids to completely close over the ocular surface
what is the eyelid margin?
identified by the gray line of meibomian gland orifices that is important to identify when closing the eyelid surgically
what is entropion?
rolling in of the eyelid margin that results in hairs touching the ocular surface
what is exposure keratoconjunctivitis?
ocular surface inflammation secondary to chronic lagophthalmos - inflammation often aligns with the exposed region of the ocular surface in an ovoid or band pattern
what is lagophthalmos?
incomplete eyelid closure/coverage of the eyeball
what is the lateral canthus?
the lateral or temporal convergence of the upper & lower eyelids
what is lens-induced uveitis?
cataract formation reliably triggers intraocular inflammation & breakdown of the blood ocular barrier
what is the medial canthus?
medial or nasal convergence of the upper & lower eyelids
what is the palpebral fissure?
area outlined by the upper & lower eyelids
what is pigmentary keratitis?
most often described in brachycephalic breeds that refers to superficial corneal pigment dispersion following chronic exposure and/or irritation (often from medial canthus entropion)
what is primary glaucoma?
inherited form of glaucoma that most often involves abnormal anatomy & drainage at the iridocorneal angle
what is ptosis?
drooping of the eyelids (most evident by upper eyelid drooping) caused by sympathetic denervation to the eyelid
what is secondary glaucoma?
any form of glaucoma that doesn’t originate from a heritable disorder of the ICA that is most commonly associated with uveitis, hyphema, & neoplasia
T/F: lens luxation-associated glaucoma is sometimes categorized as ‘secondary’ although it relates to a primary inherited condition
TRUE
what is a tarsorrhapy?
surgical procedure in which the eyelids are sutured together
what is the tarsus?
fibrocartilaginous layer of the eyelid that contains the meibomian glands
what is the holding layer for surgical eyelid closures?
tarsus!!!
what is trichiasis?
hair growing from normal skin that reach the cornea/conjunctival surface - seen a lot with entropion, but we usually use this term when describing hairs from the nasal folds that are directed towards the eye in brachycephalic dogs
what are the 4 layers of the eyelid listed from superficial to deep?
- skin 2. muscle 3. tarsus & meibomian glands 4. conjunctiva
what is the clinical importance of the orbicularis oculi muscle? what nerve innervates it? what happens if it is damaged?
closes the eyelid like a zipper - CN VII (general somatic efferent) innervation - dyfsfunction will cause lagophthalmos
what is the clinical importance of the levator palpebrae superioris muscle? what nerve innervates it? what happens if it is damaged?
opens the upper eyelid - CN III (general somatic efferent) innervation - dysfunction will cause ptosis
what is the clinical importance of the muller’s muscle? what nerve innervates it? what happens if it is damaged?
opens the upper eyelid (general visceral efferent) innervation - dysfunction will cause ptosis
what is the key concept in understanding entropion? what must you do prior to treatment?
abnormal relationship of the eye in relation to the eyelids!!!!!! must identify the cause of the imbalance prior to treating
what is anatomic entropion?
eyelids aren’t appropriately conformed to the eye & its presence is unrelated to ocular pain, can be acquired or hereditary