Eyes And Ears Flashcards
What is auricular hypoplasia?
Microtic external ear disease commonly seen in some breeds of goat in which the external cartilage of the ear does not develop
What is auricular infarction?
Frostbite of the external ear
Blood is shunted away from the periphery and poorly perfused extremities undergo necrosis
What are common neoplasias seen on the pinna of dogs? Cats?
Dogs: sebaceous gland tumors, histiocytomas, plasmacytomas, mast cell tumors
Cats: trichoblastomas, hemangiosarcoma, squamous cell carcinoma
True or false: most neoplasias of the external acoustic meatus are malignant
True
85% cats
60% dogs
What are aural plaques?
“Equine ear papillomas”
Seen in horses >1 year old
Papilloma virus spread between horses by fly bites
Rarely resolve spontaneously
Little clinical significance
What is auricular chondritis?
Immune-mediated response targeting cartilage
Seen in cats >3 years old
Auricles are bilaterally swollen, erythematous, painful, pruritus, curled
What is feline ceruminous cystomatosis?
Cystic proliferation of ceruminous glands
Benign, blue to black appearance
Cause unknown
What are aural inflammatory polyps?
Non-neoplastic polyps seen in the middle ear of cats
May protrude to nasopharynx or through tympanic membrane
What is cochleosaccular degeneration?
Hereditary deafness/inner ear disease seen in some hair/eye colors (blue and white cats, Australian cattle dogs, Australian shepherds, paint horses, etc)
Pigmented neural crest cells lack pigment -> cocheosaccular degeneration -> deafness
Why are retinal dyplasias a utero event in herbivores but can be utero or post-natal in carnivores?
Herbivore retina is fully developed at birth
Carnivore retina continues to develop 6 weeks postnatally
What is synophthalmia and what animals are known to be affected?
Fused globes due to failure of division
Sheep- veratrum californicum ingestion
What are causes of secondary glaucoma and what is the main pathology behind this?
Fibrovascular proliferation
Len luxation
Inflammation
Intraocular neoplasia
ALL occlude drainage angles
What histologic lesions would you see with glaucoma?
Retinal atrophy
Collapse of iridocorneal angle
Optic nerve head cupping
Scleral thinning
What is a developmental anomaly composed of ectopic hair follicles and adnexal glands on the cornea or conjunctiva?
Dermoid
What neoplasia is associated with lightly or non-pigmented skin?
Squamous cell carcinoma
What is a possible sequelae of chronic ulceration, most commonly seen in cats, and includes increased pigmentation of the cornea?
Corneal sequestrum
Persistent pupillary membrane is a persistence of what structure? In which animals is this most commonly seen?
Perilenticular vascular network
Dogs
What are the most common ocular neoplasias in cats?
- Melanoma
2. Post -traumatic ocular sarcoma
What is post-traumatic ocular sarcoma?
Highly invasive malignant neoplasia that is thought to arise from lens epithelium
Second most common ocular neoplasia in cats
Develops multiple years after trauma or severe disease
What is orbital meningioma?
Orbital neoplasia of dogs
Causes exophthalmos, vision loss, and optic nerve degeration
What do “bubbling” morgagnian vacuoles in lens histopathology indicate?
Cataracts
