Eyes And Ears

Question 1

What is auricular hypoplasia?

Answer 1

Microtic external ear disease commonly seen in some breeds of goat in which the external cartilage of the ear does not develop

Question 2

What is auricular infarction?

Answer 2

Frostbite of the external ear

Blood is shunted away from the periphery and poorly perfused extremities undergo necrosis

Question 3

What are common neoplasias seen on the pinna of dogs? Cats?

Answer 3

Dogs: sebaceous gland tumors, histiocytomas, plasmacytomas, mast cell tumors

Cats: trichoblastomas, hemangiosarcoma, squamous cell carcinoma

Question 4

True or false: most neoplasias of the external acoustic meatus are malignant

Answer 4

True

85% cats
60% dogs

Question 5

What are aural plaques?

Answer 5

“Equine ear papillomas”

Seen in horses >1 year old

Papilloma virus spread between horses by fly bites

Rarely resolve spontaneously

Little clinical significance

Question 6

What is auricular chondritis?

Answer 6

Immune-mediated response targeting cartilage

Seen in cats >3 years old

Auricles are bilaterally swollen, erythematous, painful, pruritus, curled

Question 7

What is feline ceruminous cystomatosis?

Answer 7

Cystic proliferation of ceruminous glands

Benign, blue to black appearance

Cause unknown

Question 8

What are aural inflammatory polyps?

Answer 8

Non-neoplastic polyps seen in the middle ear of cats

May protrude to nasopharynx or through tympanic membrane

Question 9

What is cochleosaccular degeneration?

Answer 9

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

Question 10

Why are retinal dyplasias a utero event in herbivores but can be utero or post-natal in carnivores?

Answer 10

Herbivore retina is fully developed at birth

Carnivore retina continues to develop 6 weeks postnatally

Question 11

What is synophthalmia and what animals are known to be affected?

Answer 11

Fused globes due to failure of division

Sheep- veratrum californicum ingestion

Question 12

What are causes of secondary glaucoma and what is the main pathology behind this?

Answer 12

Fibrovascular proliferation
Len luxation
Inflammation
Intraocular neoplasia

ALL occlude drainage angles

Question 13

What histologic lesions would you see with glaucoma?

Answer 13

Retinal atrophy

Collapse of iridocorneal angle

Optic nerve head cupping

Scleral thinning

Question 14

What is a developmental anomaly composed of ectopic hair follicles and adnexal glands on the cornea or conjunctiva?

Answer 14

Dermoid

Question 15

What neoplasia is associated with lightly or non-pigmented skin?

Answer 15

Squamous cell carcinoma

Question 16

What is a possible sequelae of chronic ulceration, most commonly seen in cats, and includes increased pigmentation of the cornea?

Answer 16

Corneal sequestrum

Question 17

Persistent pupillary membrane is a persistence of what structure? In which animals is this most commonly seen?

Answer 17

Perilenticular vascular network

Dogs

Question 18

What are the most common ocular neoplasias in cats?

Answer 18

1. Melanoma

2. Post -traumatic ocular sarcoma

Question 19

What is post-traumatic ocular sarcoma?

Answer 19

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

Question 20

What is orbital meningioma?

Answer 20

Orbital neoplasia of dogs

Causes exophthalmos, vision loss, and optic nerve degeration

Question 21

What do “bubbling” morgagnian vacuoles in lens histopathology indicate?

Answer 21

Cataracts