Lecture 8: Aural Pathology

Question 1

What makes up the external ear

Answer 1

auricle (pinna) and external acoustic meatus

Question 2

Identify structures in red and green

Answer 2

Red: auricle/pinnae
Green: external acoustic meatus

Question 3

histo of external ear- what is indicated by 1

Answer 3

Ceruminous glands

Question 4

What are the common routes of injury to external ear

Answer 4

1. Extension from external environment
2. Hematogenous
3. Extension from middle ear

Question 5

What are some common responses from injury to external ear

Answer 5

inflammation, fibrosis, neoplasia, hyperplasia

Question 6

what is otitis externa

Answer 6

inflammation of external ear

Question 7

what species is otitis externa most common in

Answer 7

dogs

Question 8

what are some causes of otitis externa

Answer 8

hypersensitivity reactions, ectoparasites, FB—> secondarily infected with bacteria and yeasts

Question 9

what are some sequela of otitis externa

Answer 9

stenosis—> progression to otitis media

patient induced aural hematoma

Question 10

what are some causes of infarction to external ear

Answer 10

1. bacterial septicemia (salmonella)
2. Vasculitis
3. Viruses- FIP
4. Frostbite
5. Toxins- ergot

Question 11

What wrong in these pictures

Answer 11

left: frostbite
Right: infarct- bacterial septicema

Question 12

what are some gross findings of aural hematomas

Answer 12

swollen, warm, hyperemic, heavy, heals by fibrosis, may be deformed

Question 13

cat ear- what ectoparasite is likely

Answer 13

notoedres cati

Question 14

Pig ear- what ectoparasite is likely

Answer 14

sarcoptes scabei

Question 15

rabbit ear- what ectoparasite is likely

Answer 15

Psoroptes cuniculi

Question 16

what is dermatophilosis

Answer 16

rain rot

Question 17

what is cause of dermatophilosis

Answer 17

dermatophilus congolensis

Question 18

t or f: dermatophilus congolensis is zoonotic

Answer 18

true

Question 19

what is pathogenesis of dermatophilosis

Answer 19

transmitted from dam to offspring

Question 20

what is the gross appearance of dermatophilosis

Answer 20

crusting and exudative dermatitis

Question 21

sheep presents with crusting on body and this was histo- what wrong

Answer 21

Dermatophilosis- caused by dermatophilus congolensi

Question 22

what are some most common external ear neoplasms in dogs

Answer 22

1. Sebaceous gland tumors
2. Histiocytoma
3. Plasmocytomas
4. MCt

Question 23

what are some of the most common external ear neoplasms in cats

Answer 23

1. Basal cell tumor
2. Vascular tumor (hemagioma/hemagiosarcoma)
3. SCC

Question 24

what are some common external ear neoplasms in dogs and cats

And where do they originate

Answer 24

adenoma, adenocarcinoma

Ceruminous gland origin

Question 25

cat Ear- notice the bilateral tumors and in lightly pigmented areas- what is top differential

Answer 25

SCC

Question 26

what is auricular agenesis/aplasia

Answer 26

no external ear development

Question 27

what species/breeds is auricular hypoplasia normal in

Answer 27

La Mancha goat and Scottish fold cats

Question 28

what is atresia of external acoustic meatus and what is cause

Answer 28

narrowing of external acoustic meatus Cause: congenital or secondary to trauma

Question 29

the middle ear communicates with the pharynx via the __

Answer 29

eustachian tube

Question 30

what are the routes of injury in the middle ear

Answer 30

1. Migration along vascular or neural pathways 2. Extension from perforation of tympanic membrane 3. Nasopharyngeal ascending infections via Eustachian tube

Question 31

what are some common responses to injury of middle ear

Answer 31

1. Inflammation 2. Impaired mucociliary clearance 3. Formation of inflammatory polyps 4. Horners syndrome

Question 32

what is otitis media

Answer 32

inflammation of middle ear

Question 33

what species most commonly get otitis media

Answer 33

ruminants and pigs

Question 34

what causes otitis media in ruminants and pigs/ what route

Answer 34

nasopharyngeal ascending infection

Question 35

what wrong

Answer 35

bilateral suppurative otitis media

Question 36

what species are nasopharyngeal polyps most common in

Answer 36

cats <2yrs

Question 37

what are some predisposing factors to nasopharyngeal polyps

Answer 37

chronic infections, otitis media, congenital defects

Question 38

what are some clinical signs of nasopharyngeal polyps

Answer 38

upper respiratory discharge, sneezing, dyspnea, strider, voice change, dysphasia, head tilt

Question 39

from cat- what wrong

Answer 39

Nasopharyngeal polyp

Question 40

what cranial nerves are present in inner ear

Answer 40

V, VII, and VIII

Question 41

all cranial nerves in inner ear are embedded in ___

Answer 41

petrous portion of temporal bone

Question 42

what is the function of inner ear

Answer 42

vestibular system- critical for balance

Question 43

what are some routes of injury to inner ear

Answer 43

1. Extension from middle ear- most common 2. Migration along vascular or neural pathways

Question 44

what are some common responses to inner ear injuries

Answer 44

1. Sensory cell degeneration/ death 2. Inflammation with extension into surrounding bone—> osteomyelitis

Question 45

what are some clinical signs of vestibular disease

Answer 45

head tilt, circling facial paralysis, ataxia

Question 46

what are some causes of vestibular disease

Answer 46

congenital, idiopathic, concurrent otitis media/interna, aural or intracranial neoplasia

Question 47

what is otitis interna

Answer 47

inflammation of inner ear

Question 48

What wrong and what can it result in

Answer 48

otitis interna—> can result in meningitis, ventriculitis, encephalitis

Question 49

what wrong and what cause

Answer 49

aural plaques caused by papillomavirus

Question 50

what is feline Ceruminous cystomatosis

Answer 50

benign, idiopathic cystic dilation and non-neoplastic proliferation of Ceruminous glands

Question 51

Cat ear- what wrong

Answer 51

Feline Ceruminous cystomatosis