Week 2 Eyelids Study Questions Flashcards
what is the function of the tarsal plate
provides surface for muscle attachment, gives eyelid margin rigidity
what type of glands are meibomian glands? where are they located? what is their function?
sebaceous glands, located along eyelid margin at mucocutaneous junction, they secrete lipid layer of precorneal tear film
what muscle functions to close the eyelids? whats its innervation?
orbicularis oculi, innervated by palpebral branch of CN VII
what muscle functions to close the eyelids? what is its innervation?
levator palpebral superioris, innervated by palpebral branch of CN III
what structures anchor the eyelids to the orbital rim?
retractor anguli muscle
what muscle provides “tone” to the upper eyelid? whats its innervation?
muller’s muscle, innervated by sympathetic nerve. deviated in horner’s syndrome = droopy eyelid
what is the term for a normal misdirected hair?
trichiasis
what is the term for an abnormal hair exiting a Meibomian gland opening?
Distichiasis
what is the term for an abnormal hair exiting the conjunctiva?
ectopic cilia
what is a congenital defect in the upper eyelid of a cat?
coloboma
what causes ophthalmia neonatorum
in utero FHV-1 or bacteria in dogs
what are the clinical signs, breed dispositions, and treatment of entropion
blepharospasm, periocular wetting, staining, corneal vascularization, corneal fibrosis, corneal ulcer, corneal pigment
sharpei, lab, bulldog, golden, mastiff, any breed with excessive loose skin
brachycepalic dogs and cats - medial canthal entropion
topical lubricants or surgery - permanent lateral canthoplasty & modified holtz-celsus
what are the clinical signs, breed dispositions, and treatment of ectropion
hyperemia, chemosis, mucoid discharge
spaniels, hounds, great dane, st bernard, bloodhound
tear supplement, surgical fix- full thickness wedge resection, of lower eyelid or permanent, lateral canthoplasty
what 2 conditions of the eyelid are associated with entropion in dogs
macroblepharon and lateral canthal laxity
what are two procedures used to correct entropion? which one is performed first?
permanent lateral canthoplasty (1st) & modified holtz-celcius
what are the three most common eyelid tumors in the dog
meibomian gland adenoma, papilloma, melanoma
what are the three most common eyelid tumors in the cat
Squamous cell carcinoma, basal cell carcinoma, mast cell
what are the three most common eyelid tumors in the horse
Squamous cell carinoma, sarcoid, melanoma
what is the most common eyelid tumor in the cow
Squamous cell carinoma
are eyelid tumors in dogs more commonly benign or malignant?
benign
how much of the eyelid margin can be excised while allowing primary closure
25-33%
what types of adjunctive therapy are recommended for squamous cell carcinoma
cryosurgery, radiation, intralesional chemo
in the horse, what are the best treatment options for squamous cell carcinoma of the eyelid or medial canthus?
surgical excision + adjunctive therapy
cyrosurgery, hyperthermia, radiation, chemo, photohynamic
what is chalazion and how is it treated?
meibomian granuloma, warm compresses, topical +/- systemic abx
what is blepharitis? what are the common causes in dogs and cats?
inflammation of the eyelids
allergic, pyogranulomatous, parasites (mites), equine habronemiasis, immune-mediated
what parasitic infection in horses is a differential diagnosis for squamous cell carcinoma
habronemiasis
what principles should you keep in mind when you repair eyelid lacerations in small animals and horses
debride conservatively, only trim necrotic tissue, do complete exam, primary intention using 2 layer closure (subconjunctival and skin)
