Special Senses pt 3 Flashcards
What is a descemetocele?
deep ulcer down to Descemet’s membrane
Gorp has come back to the clinic again. This time, his eye is affected by this lesion. What is your primary differential?
Descemetocele
What is an indolent ulcer? common species? what happens? treatment?
failure of normal ulcer healing with no underlying specific cause (often initiated by trauma)
dogs
newly formed epithelium fails to adhere to the underlying stroma
debridement
What is a melting ulcer?
an ulcer where release of lytic enzymes leads to stromal malacia/necrosis
Melting ulcers can be sterile, but they usually involve ____ or _____ infections. Name the two examples given in class. are they opportunistic pathogens or ocular pathogens?
bacterial, fungal
gram (-) bacteria
fungus common in horses (keratomycosis)
opportunistic
Gorp is back. Again. This poor dog. This is his ocular lesion. What do you think it is? What is your primary differential for cause?
melting ulcer/suppurative keratomalacia
gram (-) bacteria
What is keratoconjunctivitis sicca (KCS)? common species & breeds? Clinical or pathological?
desiccation of the cornea due to reduced quantity of tear film
dogs
clinical
What is an ocular dermoid?
Developmental abnormality where ectopic hair follicles and adnexal glands occur on the cornea or bulbar conjunctiva
Define these words:
1. Hamartoma
2. Choristoma
Which category does an ocular dermoid fall in?
- aberrant proliferation of normal tissue in a normal location
- aberrant proliferation of normal tissue in an abnormal location
ocular dermoids are choristomas
Poor Gorp the cat. he is back again, this time with this ocular lesion. What is it?
Ocular dermoid
What is the other name of pink eye in cattle?
infectious bovine keratoconjunctivitis
Infectious bovine keratoconjunctivitis:
1. etiology?
2. can have recurrent _____.
3. time of year of outbreaks? why?
4. signalment?
- gram (+) bacteria: Moraxella bovis
- infectious bovine rhinotracheitis
- summer. flies are important vectors
- calves > adults
What can infectious bovine keratoconjunctivitis progress to?
phthisis bulbi (end-stage eye, scaring and atrophy)
How do you tell between infectious bovine keratoconjunctivitis and hypopyon from sepsis?
presence of conjunctivitis
A cow comes in to your practice with this lesion in July. What is your primary differential?
Infectious bovine keratoconjunctivitis
What is the etiology of herpesvirus keratitis?
feline herpesvirus 1
what is the most common cause of keratitis in cats? typical signalment?
herpesvirus keratitis caused by feline herpes virus 1
kittens, shelter cats
herpesvirus keratitis:
1. what does it target?
2. why is it hard to prove causality?
- upper resp tract, conjunctiva, cornea
- most cats exposed during life to feline herpesvirus 1 and FHV-1 DNA can be detected on the cornea of normal cats
What are the clinical signs of herpesvirus keratitis in cats?
rhinotracheitis, conjunctivitis, +/- keratitis common in young cats
dendritic ulcers are pathognomonic !!!!
What pathology is this picture of?
Herpesvirus keratitis
Herpesvirus keratitis in cats is associated with ____ and _____
feline corneal sequestrum
feline eosinophilic keratitis
What are the secondary bacterial infections that are associated with herpesvirus keratitis?
chlamydia felis
mycoplasma felis
what viruses can cause conjunctivitis and resp signs in young cats? How do you differentiate the two based on clinical signs?
- Feline calicivirus
- feline herpesvirus 1
calicivirus is usually associated with oral ulcers, herpesvirus 1 isn’t
Gorp the cat is back again! Bad luck for Gorps at your clinic. This is his lesion. He also has rhinotracheitis and conjunctivitis. What is your primary differential? What other thing could it be and how could you tell the difference?
herpesvirus keratitis
also be calicivirus
looks at mouth for oral ulcers (if yes, then calicivirus). also dendritic ulcers are pathognomic of herpesvirus keratitis
Eosinophilic keratitis:
1. species?
2. gross features?
3. cytology reveals what?
- cats > horses
- cats - begins laterally as raised white to pink plaques on the cornea/conjunctiva
- abundant eosinophils and some mast cells
Gorp the cat is back AGAIN!!!!! This time he has this ocular lesion. What is your primary differential?
eosinophilic keratitis
corneal sequestrum:
1. common species?
2. secondary to what?
3. gross lesion?
4. histo lesion?
5. common signalment?
- cats > horses & dogs
- chronic ulceration
- central accumulation of orange to brown pigment in the superficial stroma
- necrotic stroma
- Persian, Himalayan, Siamese cats
What is this lesion? Note the orange-brown pigment.
Hint: this is a cat named Gorp
corneal sequestrum
Chronic superficial keratitis of dogs:
1. AKA?
2. breeds?
3. 1 eye or 2 eyes?
4. _____-_____ disease targeting _____ ______ of the cornea
5. associated with what?
- Pannus
- German Shepherds and Sighthounds
- 2 eyes
- immune-mediated, altered antigen
- higher altitudes and solar radiation
Gross lesions of pannus?
begins as a redness and thickening of the lateral conjunctiva, progresses asa plaque axially across the cornea
become pigmented
Gorp the dog is back again. He has changed breeds to a German Shepherd, and his owner spends a lot of time with him running outside. What is this lesion?
Pannus AKA chronic superficial keratitis of dogs
Limbal melanocytic neoplasia:
1. majority are ____ _____
2. species?
- benign melanocytoma
- dogs > cats
what are the 3 neoplasias of the cornea that we should know?
limbal melanocytic neoplasia
corneal squamous cell carcinomas
corneal hemangiosarcomas
Gorp’s eye is really not doing ok. He is back. This is his eye. What is your primary differential?
Limbal melanocytic neoplasia
Persistent pupillary membranes:
1. congenital or acquired?
2. common or uncommon?
3. what species?
4. what is it
5. How worried should you be when you find it in necropsy?
- congenital
- common
- dogs
- persistence of fibrovascular structures that vascularized the lens during development
- not very. usually incidental, unless they directly contact the lens or cornea
Gorp the dog had a son (yay!). This is Gorp junior’s eye (Gorp jr. is like 6 mo old). What do you think is going on?
Persistent pupillary membranes
You find this lesion on necropsy. What is is?
Persistent pupillary membranes
What is the name for inflammation of the uvea?
uveitis
Uveal cysts:
1. common signalment?
2. What are they?
3. Where do they come from?
- dogs > cats (but Bermese cats common)
- Round translucent blackcysts attached to the iris or free-floating in the anterior chamber
- arise from fluid accumulation within the iris or ciliary body
Uveal cysts:
1. usually benign or malignant?
2. what is the exception? why?
- benign
- golden retrievers and Irish wolfhounds - precursor to glaucoma and pigmentary uveitis of Goldens
Gorp is back. He practically lives at the clinic now. This is the lesion he is presenting with. What is it?
Uveal cyst
