Lecture 2 Flashcards
what do you see
epiphora: tear staining on the face originating from the medial canthus
tears flow onto the face, stains the hair, and can cause moist dermatitis
what causes epiphora?
increased production from irritation
decreased outflow from an obstruction of nasolacrimal system
what is imperforate puncta? how do you treat?
the lower tear duct opening has not developed, can cause epiphora due to decreased tear drainage
open the imperforate puncta and give topical steroids to prevent closure
what is dacryocystitis? how do you treat?
inflammation of the nasolacrimal duct and it blocks the nasolacrimal system.
can be caused by an obstruction like a grass awn, neoplasm, dental disease, facial bone fractures, etc.
tx: flush the NL system, give topical steroids/antibiotics, but can reoccur. do not use long term oral antibiotics
canine conjunctivitis is often caused by….
you’ll see…
allergies–>associated with atopic dermatitis
will see chemosis (edema of conjunctiva) and hyperemia
how should you treat allergic canine conjunctivitis?
treat underlying atopy
topical steroids and anti histamine (Pataday 0.2% 1-2x daily, these are antihistamine drops)
list some causes of feline conjunctivitis
herpesvirus: will also have URT dz
chlamydophila felis: mostly chemosis
mycoplasma: uncommon
a cute wittle kimten comes to you with conjunctivitis. will you treat this cat?
assuming it’s herpes, no, it is self limiting
if the cat doesn’t improve and I think it might be chlamydia, I would give oral doxycyline for 4 weeks 2x day
what is this? it is pathognomonic for…
a dendritic ulcer: you can see the branching fluorescin stain in the superficial cornea and some corneal vessels laterally
pathognomonic for feline herpesvirus keratitis, often with concurrent conjunctivitis
how can you treat feline herpesvirus keratitis?
can give antivirals
systemic: famciclovir
topical: cidofovir, trifluridine, idoxuridine
oral lysine (no real evidence it works tho)
could do topical broad spec antibitiocs
warn owners that recurrance is common
what is neonatal ophthalmia?
primary FHV infection with secondary bacterial infection before the eyelids open, may be discharge
give topical antibiotics and open the eyelids to give this
what do you see? what is the cause?
corneal sequestrum: lateral central black superficial lesion with vessels encircling
this is a necrotic cornea, this is unqiue to the cat, most often in brachy cat breeds. can be a primary dystrophy or after a corneal ulceration/irritation
what do you see?
a corneal sequestrum caused by lower entropion, can see vessels encircling the lesion
what things determine the treatment plan for a corneal sequestrum in a cat?
level of discomfort and the depth
if comfortable and it’s superficial, let it slough naturally! steroids and antibiotics have no effect on these ones! this process can take months to years
if its painful and/or deep, do a superficial keratectomy (remove it), +/- a conjunctival graft, corneoconjunctival transposition, corneal transplant
this is a cat. what do you see, what is #1 ddx and how will you confirm?
eosinophilic keratitis: pink with white deposits on the surface, superficial blood vessels on lateral cornea
this is a proliferative disease of the superficial cornea. there is NO association with eosinophilic granuloma complex
do cytology of corneal scrapings revealing lymphocytes, eosinohpils, mast cells, neutrophils
how do you treat eosinophilic keratitis?
0.1% dexamethasone or 0.1% prednisolone QID initially
cyclosporin or tacrolimus and taper slowly
recurrance is common
true or false: cats with eosinophilic keratitis respond very fast to treatment
true! within 2 weeks they can be normal!
this is a 12yo shiz tzu. what do you see? ddx?
corneal degeneration: dense white corneal opacity rim around a clear zone, some white areas. the clear zones are areas in which calcium has flaked off and this dog had previous ulcers.
usually will have a gritty look to them, calcium and/or lipid deposits, flakes can cause an ulcer too
what is this and how do you treat it
corneal degeneration: can see the grittty mineral appearance, there is also a desmetocele
treatment:
1) remove the mineral either by doing a keratectomy + corneoconjunctival transportation (best option) or a corneal burr
2) EDTA to get rid of mineral (doesn’t work great), requires the epithelium to be absent and often used with the burr
3) lubricants
DO NOT USE topical steroids
this dog had corneal degernation. what treatment was done?
corneaoconjunctival transportation, essentially moving the limbus down. super effective for non healing mineralization or descmetoceles
what is this? treatment?
corneal dystrophy: fat deposit, does not cause vision issues, not painful, often in young dogs, we don’t really know why they happen, usually bilateral
can leave alone or give cyclosporin to get rid of them but it takes 6-12 months
DO NOT USE TOPICAL STEROIDS
what do you see here? cause?
endothelial dystrophy: can see OU temporal blue/white cloudiness. essentially the endothelial cells start to die off earlier than they should, and the cells can no longer pump fluid out of the cornea to keep it dehydrated so you get corneal edema. endothelial cells cannot be replaced.
true or false: endothelial dystrophy begins medial and moves lateral
false! starts lateral and moves medial
what are 2 common sequelae to endothelial dystrophy?
bullae (fluid filled sacs) due to fluid accumulation
superficial ulceration due to fluid sac rupture
how do you treat endothelial dystrophy?
thermokeratoplasty: cauterize the superficial cornea to limit edema (burn the cornea), used when ulcers are present, and this heals ulcers in 90% of cases within 2-4 weeks
keratectomy + conjunctival graft: this slows down/stops progression and can improve corneal edema, the graft is placed on lateral 3rd of the cornea
can do corneal transplant but riskier and harder to find donator corneas
hypertonic saline to suck fluid out of cornea: brian doesn’t do this
what do you see here?
corneal edema with a superficial ulcer
what do you see here?
this is thermokeratoplasty to treat ulcers/endothelial dystrophy: cauterize the cornea to get blood vessels to come in and heal the ulcer. ulcers usually do not recurr if you do this.
what is the difference between endothelial dystrophy and endothelial degeneration
endothelial dystrophy: the cells start to die off earlier than they should
endothelial degeneration: something is damaging the endothelial cells, such as
- anterior uveitis, glaucoma, trauma, endothelitis (rare)
treat the underlying disease and cause of damage, although damage may be permanant
this cat was normal yesterday. what is this?
bullous keratopathy: extreme corneal cloudiness and bullae over the medial cornea
this can occur in hours! can be focal or diffuse, not very common, can cause perforation but rare
what is this? what is the cause? treatment?
bollous keratopathy: causing protrusion of the cornea
cause is unknown, thought to be an endothelial cell malfunction. a lot of these cats have chronic uveitis and are on topical steroids.
tx: stop topical steroids, place a 3rd eyelid flap, leave flap for 2 weeks and givetopical antibiotic while flap is there,and the prognosis is very good
cats on what drug have an increased risk of bullous keratopathy?
cyclosporin
we dont know why
what is this ocular condition called?
macropalpebral fissure syndrome: OU laterally displaced globes, lateral strabismus, extensive showing of sclera, large eyelid opening resulting in inability to close eyelids properly (lagophthalmia)
this is a pug, how did this lesion happen?
this is macropalpebral fissure syndrome and corneal irritation leading to hyperkeratosis/corneal pigment (the eye trying to protect itself)
this is a pug. what do you see here?
macropalpebral fissure syndrome! medial entropion causing irritation of the cornea
what is going on in this pug?
chronic macropalpebral fissure syndrome leading to severe hyperpigmentation of the cornea and consequent blindness (eye trying to protect the cornea)