Ear Pathology Flashcards
What are the top ten canine claims?
- Atopic or allergic dermatitis
- Ear Infection
- Benign skin neoplasia
- Pyoderma
- Osteoarthritis
- Periodontitis/tooth Infection
- Upset stomach
- Intestinal inflammation/diarrhea
- Cystitis or urinary tract disease
- Anal gland sacculitis/ expression
The ear is the extension of?
The skin
Function of the Ear
The ear is the organ of _________ and _________
1. Collect _________ stimuli
2. Transduce the _________ stimuli
3. Transmit nerve impulses to _____
Function of the Ear
The ear is the organ of hearing and balance
1. Collect auditory stimuli
2. Transduce the mechanical stimuli
3. Transmit nerve impulses to CNS
Big ear, big oracle –> advantageous for this species
The ________ collects the sound. The external ear starts with the _____ –> external acoustic _______ which has the ______ and ______ part.
–> the external ear ends with the ________ _________.
The oracle collects the sound. The external ear starrs with the oracle –> external acousitic medius whihc has the vertical and horizontal part –> the external ear ends with the tympanic membrane.
Middle ear = tympanic cavity (tymanci bulla with cavity) including the ossicles (small bones in middle ear), auditory tube conects tot he pharynx whihc is apart of the middle ear.
Inner ear = cochlea, and the semi circular canals. These two components are within the inner ear. When you have otitis interna, these are the affected structures.
The vesibular and cochlear nerve connect to the vestibular aparatus and the cochlea. Whenver the animal has otitis interna, even otitis media, that extends into otiis interna there may be some nerve dmage that manifests as neuro disease (e.g. Horner’s)
The ear is composed of three major parts
1. External ear:
* _______ (or ______)
* ________ ________ _________
2. Middle ear:
* ?
* ?
* ?
* ? –> ?
3. Inner ear:
* Composed of a _________ labyrinth enclosed in the ________ bone.
The ear is composed of three major parts
1. External ear:
* Auricle (or pinna)
* External auditory meatus.
2. Middle ear:
* Tympanic membrane (ear drum)
* Tympanic cavity
* Auditory ossicles (malleolus, incus and stapes)
* Auditory (Eustachian) tube; connected to the pharynx
3. Inner ear:
* Composed of a membranous labyrinth enclosed in the temporal bone.
In external ear canal, there is _______ cartilage. Very ______. Very __. When animal has otitis externa, ear feels very ____ and _____ – proliferation of ______ and cartilage is ________.
In external ear canal, there is elastic cartilage. Very pliable. Very soft. When animal has otitis externa, ear feels very hard and stiff – proliferation of tissue and cartilage is ossified.
Components of the External Ear
* _________ skin –> any diseases of tegument system can occur here = ?
* ______ or _____
* ________ cartilage
* ________ ear canal/________ _______
* ________ membrane (________)
Functions of the External Ear
* ________ and _______ sound waves
Components of the External Ear
* Haired skin –> any diseases of tegument system can occur here = atopic dermatitis, pyoderma, otitis externa
* Auricle or Pinna
* Elastic cartilage
* External ear canal/auditory meatus
* Tympanic membrane (eardrum)
Functions of the External Ear
* Collect and convey sound waves
Label this image accordingly
Inflammation cna happen on both sides since hair on both side
Ceruminous Glands
* Located within the skin of the?
* Simple, ______, _____ ________ glands
* Secrete ear _____, also known as ________, is a mixture of viscous secretions from
________ glands, sloughed ____ cells, and less-viscous ones from modified
________ ______ glands (________ glands)
They become tumors: ?
Dx by _______. Mass in external ear canal.
Ceruminous Glands
* Located within the skin of the external acoustic canal
* Simple, coiled, tubular apocrine glands
* Secrete Ear wax, also known as cerumen, is a mixture of viscous secretions from
sebaceous glands, sloughed skin cells, and less-viscous ones from modified
apocrine sweat glands (ceruminous glands)
They become tumors: ceruminous adenocarcnimoma/adenoma. Dx by histopath. Mass in external ear canal.
Label the image accordingly
What is pictured below?
Ceruminous glands
Diagnostics for External Ear Diseases
Pinna & Wall of the Canal
* ________ examination –> make sure to do this;
- if see lesions, do _______!
* Cytology (________ smears and ____ preparations)
* _______ and _____ skin ______
* _________
* _______ and ______ culture and sensitivity
* Fine-______ aspirates
* ________
Diagnostics for External Ear Diseases
Pinna & Wall of the Canal
* Otoscopic examination –> make sure to do this;
- if see lesions, do cytology!
* Cytology (impression smears and tape
preparations)
* Superficial and deep skin scrapings
* Trichograms
* Bacterial and fungal culture and sensitivity
* Fine-needle aspirates
* Biopsy
Cytollogy = Neutrophils engulfing cocci (on left) –> pyoderma
deep- mites
tricho - hair follicle problem
bacterial - infectious agents on cytology
mass - fine needle
biopsy - mass
top left is impression smear
top right is tape
Pinna & Wall of the Canal
* Cytology (swab)
Numerous cocci, rods (red arrows) and Malassezia pachydermatis
(black arrow) are present
Adult mite and ovum of Otodectes cynotis
stray cat with itchy ears!
Otitis Externa
* Otitis externa is ________ a primary condition
- oftentimes animal will have ______ disease such as a ?
* Usually arises from the interaction of ________ factors, ______ causes, and ______ causes
* more common in ____»_space;» ____
* Clinical signs:
* Exudate, hemorrhage
* Auricles tend to be _____, _____, _______, and ________
* Chronic cases: ______ epidermis, _____ external ear canal, _______ (_______ of skin)
* If left untreated, ________ _______ of the ear canals will become necessary
Otitis Externa
* Otitis externa is rarely a primary condition
- oftentimes animal will have underlying disease.
- food allergy, ectoparasite infestation, etc.
* Usually arises from the interaction of predisposing factors,
primary causes, and secondary causes
* more common in Dogs»_space;» Cats
* Clinical signs:
* Exudate, hemorrhage
* Auricles tend to be red, warm, edematous, and painful
* Chronic cases: thickened epidermis, stiff external ear canal, stenosis (prolferation of skin)
* If left untreated, surgical removal of the ear canals will become
necessary
Predisposed to otitis externa b/c floppy ears, not much air flow, lot of hair
swimming also predisposes them
Predisposing Factors of Otitis Externa?
Christine’s TOEES
Obstructive: mass, polyp causes this too
Secondary causes of otitis externa
treat for seconary then investigate primary.
this is what you ususally see
Acute otitis
- diffusely errythematous
- pale yellow to brown exudate