Lecture 7: Ocular Pathology Flashcards
Identify 1-2
- Eyelid
- Conjunctiva
what is the function of eyelid
1st line defense and forms protective barrier
what type of epithelium lines eyelid
stratified squamous epithelium
from eye- identify 1 and what is function
Meibomian glands- produce secretions that lubricate eyes
what is blepharitis
inflammation of eyelid
what is blepharedema
Edema of eyelid
what wrong
cherry eye/ prolapse of third eyelid
what breeds are predisposed to cherry eye and what causes it
bulldogs
Due to increased laxity of CT anchoring 3rd eyelid to periorbital tissue
what is likely dx for this benign tumor on dog eyelid
meibomian gland adenoma
what is likely dx for this tumor on cow eyelid. What other species commonly gets this
Squamous cell carcinoma
Cats
what is the conjunctiva
mucous membranes that line the front of eyes (bulbar) and insides of eyelids (palpebral) and terminate at the corneal limbus
identify 1-3
- bulbar conjunctiva
- Lacrimal gland
- Palpebral conjunctiva
What is conjunctivitis and what is it secondary to
inflammation of conjunctiva, secondary to infection or allergies
what are some common etiologies of conjunctivitis
herpesvirus, chlamydophila, mycoplasma
what is chemosis
edema of conjunctiva
What is the most common neoplasms of the conjunctiva
- Melanocytic tumors
- Hemangiomas/ hemagiosarcoma
tumor of conjunctiva- what is dx
Melanocytic tumor
what wrong
chemosis
what is the junction between cornea and sclera
limbus
identify 1-3
- Cornea
- Limbus
- Sclera
what features of the cornea allow for transparency
- No keratinized non pigmented epithelium
- Low cell density
- A vascular
what is the most common mechanism of injury to cornea
external injury (trauma, extension of eyelid/conjunctiva, chemical injury)
what is this called?
Cow has retrobulbar neoplasm caused by a retrovirus. What retrovirus, what neoplasm
exophthalmosis- protrusion of eye
Virus: BLV
Neoplasia: B cell lymphoma
what are the 4 ways the cornea responds to injury
- Ulceration
- Neovascularization
- Hyperpigmentation
- Inflammation- keratitis
what is the risk associated with neovascularization of cornea
corneal edema—> blue eye
what wrong
corneal edema
How does the cornea respond to injury that is shallow, mild and sterile
epithelial regeneration
how does the cornea respond to injury that is deep, infected, chronic
stromal fibrosis
horse eye- what is wrong
Keratomalacia- melting ulcer
what wrong and what layer is the damage down to in eye
Descemetocele leading to iris prolapse
Down to descemets membrane
What part of the eye has smooth muscle allowing for dilation/constriction—> controls diameter of pupil
iris
identify 1-2
- Iris leaflet
- Ciliary body
what structure makes aqueous (vitreous) humor
Ciliary body
describe the normal flow and drainage of aqueous humor
- Starts at ciliary body
- Moves to anterior chamber
- Drains out iridocorneal/filtration angle
identify 1-3
- Ciliary body
- Iridocorneal/ filtration angle
- Anterior chamber
increased intraocular pressure results in ___
glacuoma
what structure is between sclera and retina
choroid
what is the function of the choroid
provide nutrients to retina (capillaries)
identify 1-2
- Retina
- Choroid
identify 1-3
- Retina
- Choroid
- Sclera
what structure contains tapetum lucidum
choroid
what is the most common source of injury to uvea
hematogeous
what is uveitis
inflammation of uvea
what are some common causes of uveitis
- Infectious: bacterial, fungal, nematode migration, viral
- Immune mediated
- Trauma
- Reflex uveitis- secondary to corneal injury
what are some consequences of uveitis that effect the cornea
- Neovascularization
- Endothelia is
- Edema-blue eye
identify the changes to the cornea due to uveitis
left: neovascularization
Middle: endothelitis
Right: edema- blue eye
what are some possible causes of edema/blue eye
- FIP
- Canine adenovirus 1
- Malignant catarrhal fever