Otic surgery

Question 1

Draw a diagram of the external ear?

Answer 1

Question 2

Draw a diagram of the inner and middle ear of a dog?

Answer 2

Question 3

What are the Primary causes of Otitis Externa?

Answer 3

• Parasites
  
  • Otodectes cynotis
  • Demodex canis/cati
  • Sarcoptes scabiei
  • Notoedres cati
  • Cheyletiella spp
• Hypersensitivity and allergic disease
• Hypothyroidism
• Keratinization disorders
• Autoimmune disorders

Question 4

What are the Predisposing causes of Otitis Externa?

Answer 4

• Anatomic and conformational factors
• Excessive moisture
• Iatrogenic factors
• Obstructive ear disease

Question 5

What are perpetuating causes of otitis externa?

Answer 5

Bacteria (Staph. Intermedius, Pseudomonas aeruginosa, Proteus mirabilis, Escherichia coli, Corynebacterium spp, Enterococcus spp, Streptococcus spp)

Yeast (Malassezia pachydermis, Candida spp)

Otitis media

Progressive pathologic changes

Question 6

What are the major indications for ear surgery?

Answer 6

• Trauma (mainly pinna but sometimes external ear canal)
• Aural haematoma
• Neoplasia (pinna, external ear canal, middle ear, etc.)
• Certain cases with chronic otitis externa
• Chronic otitis media
• Infection (extension of chronic otitis externa)
• Middle ear polyps
• Cholesteatoma

Question 7

What are the most common neoplasms of the pinna?

Answer 7

Question 8

What has this cat been treated for?

Answer 8

Surgical management of pinnal squamous cell carcinoma

White cats have a tendency to develop these as their pinna tips/extremities are sensitive to UV rays.

Question 9

What is an aural haemotoma?

Answer 9

Bleed between scafa (aural cartilage) and integument

• The aetiology of aural haematoma remains unknown
• Proposed associations have included:
  
  • Otodectes cynotis
  • Otitis externa
  • Trauma
  • Autoimmunity
  • Hypersensitivity

More common on just the medial aspect in dog.

Question 10

How are aural haematomas managed?

Answer 10

• Surgical incision, drainage, and suture
• Drainage with an indwelling drain (Penrose, tube, teat tube, etc.)
• Drainage and glucocorticoid instillation
• Closed-suction drainage
• Surgical incision, drainage, and suture

Picture shows: Stitch the integument and skin to cartilage to cause adherence and heal by scarring.

Question 11

How should stitches be placed when fixing an aural haematoma?

Answer 11

Be aware of blood supply best to put them in they way shown above so you don’t occlude the blood vessels.

Question 12

How is a teat tube placed to treat an aural haematoma?

Answer 12

Question 13

What are the complications of drainage of aural haematomas?

Answer 13

• Cosmetic alterations
• Recurrence of haematoma
• Pinna necrosis

Question 14

Outline surgical management of Otitis Externa (procedures performed on external ear canal)?

Answer 14

Lateral wall resection

Vertical canal ablation

Question 15

LWR is indicated in the following circumstances?

Answer 15

• Persistent, or recurrent, otitis externa with mild, potentially reversible, hyperplasia of the epithelium and adnexae
• Neoplasia of the lateral wall of the vertical canal
• Very rarely in the management of otitis media to facilitate flushing and drainage of the bulla

Question 16

Name neoplasias of the external ear canal?

Answer 16

Question 17

What is this?

Answer 17

Ceruminous gland adenoma on left & adenocarcinoma on right

Question 18

What is a lateral wall resection and when can it be performed?

Answer 18

• The procedure does not cure the animal of its underlying disease but improves the micro-environment of the ear
• LWR will fail if there are chronic, irreversible, hyperplastic changes to the luminal epithelium or if there is ongoing otic inflammation
• Removing the lateral wall of the vertical portion of the external ear canal.
• Has been used to treat otitis externa but most causes of this are allergy and if you don’t treat the underlying cause not much use of doing this surgery as the problem will persist.

Question 19

What are some complications of lateral wall resection?

Answer 19

Not very effective for most ear disease we see.

• Postoperative pain/discomfort
• Incisional dehiscence
• Persistent otitis externa
• Persistent, unrecognised otitis media
• Failure to provide adequate drainage of the horizontal canal

Question 20

When is a vertical canal ablation indicated?

Answer 20

• Only rarely indicated
• Vertical canal only is diseased
• Hyperplastic otitis externa, trauma, neoplastic disease and polyps restricted to the vertical ear canal
• Removing both lateral and medial (so entire vertical portion) portions and ear canal

Question 21

What are complications of vertical canal ablation?

Answer 21

• Postoperative pain/discomfort
• Incisional dehiscence
• Persistent otitis externa
• Persistent, unrecognised otitis media
• Stenosis of horizontal canal
• Facial paralysis

Question 22

What are the surgical treatments of Otitis Media?

Answer 22

• Total ear canal ablation and bulla osteotomy
• Ventral bulla osteotomy

Question 23

What is the most like causative agent of this infection?

Answer 23

That looks like malassezia

Question 24

What is the most like causative agent of this infection?

Answer 24

Prominent purelent one. Most likely pseudomonas

Question 25

When is a total ear canal ablation and bulla osteotomy indicated?

Answer 25

* TECA BO is indicated in the following circumstances: * Chronic, or recurrent, otitis externa associated with irreversible, hyperplastic changes in the luminal epithelium * Failure of more conservative surgery to alleviate otitis externa or media * Neoplasia of the external ear canal * Otitis media

Question 26

What are the complications of total ear canal ablation and bulla osteotomy?

Answer 26

* Postoperative pain/discomfort * Deafness * Incisional dehiscence * Facial nerve paralysis * Vestibular disturbances * Haemorrhage * Horner’s syndrome (postganglionic fibres towards the eye run across bony prominence of ear) * Recurrence/abscess formation

Question 27

What are the classic features of Horner’s syndrome are:

Answer 27

* Anisocoria (pupils unequal size) * Ptosis of the upper eyelid * Narrowing of the palpebral fissure * Enophthalmos * Protrusion of the third eyelid

Question 28

VBO is indicated in cases with middle ear disease and the following circumstances: Photos show structures you must move out of the way to get access to it.

Answer 28

Cases in which a TECA is not required Certain brachycephalic breeds of dog Often used in the cat * Anatomy of the bulla * Inflammatory polypoid disease in the absence of chronic otitis externa

Question 29

What are Complications of VBO?

Answer 29

* Postoperative pain/discomfort * Deafness * Incisional dehiscence * Facial nerve paralysis * Vestibular disturbances * Haemorrhage * Horner’s syndrome * Recurrence/abscess formation

Question 31

What is this?

Answer 31

**Cholesteatoma** Slowly enlarging, cystic lesions within the middle ear cavity Lined with stratified squamous epithelium and keratin squames Thought to arise when a pocket of the tympanic membrane comes into contact with, and adheres to, inflamed mucosa within the middle ear. Treatment – TECA BO or VBO

Question 32

What can be seen here?

Answer 32

**_Inflammatory polyps in cats_** * Aetiology unknown (early exposure to cat flu??) * Often emanate from tympanic bulla * Nasopharyngeal * Horizontal ear canal * Otitis media * Start point commonly in middle ear: then they can grow one of two ways--\> towards pharynx or--\>external ear canal * Cats often present if polyp in pharynx as diff breathing. * Do not forget to examine the ear canals in cases of nasopharyngeal polyps and the nasopharynx in cases of polyps in the external ear canal

Question 33

What is seen here?

Answer 33

**Primary Secretory Otitis Media** * Obstruction to the auditory tube means middle cannot drain properly. SO they end up with a bulging tympanic membrane as seen from an otoscope. * Cavalier King Charles spaniels * Syringomyelia (Chiari-like malformation of the calvarium/caudal fossa) * Commonly bilateral * Affected dogs will have reduced hearing * Bulging pars flaccida * Myringotomy + flushing of affected tympanic bulla * May require multiple treatments