Surgical Conditions of the Ear

Question 1

what conditions can affect the pinnae of the ears?

Answer 1

trauma (lacerations)

aural hematoma due to excessive head shaking

neoplasia due to sun exposure (squamous cell carcinoma, melanoma)

Question 2

how can we avoid neoplasia on ear pinnae?

Answer 2

high high factor childrens sunscreen on high risk areas (esp if white fur/hairless/unpigmented skin)

Question 3

what is the most common infection of the external ear canal in dogs?

Answer 3

otitis externa- primarily dermatological

Question 4

what are the possible causes of otitis externa?

Answer 4

immune-mediated (pollen/moulds)

parasitic infection (otodectes cynotis)

poor aeration

Question 5

what can cause poor aeration to the ears?

Answer 5

floppy ears

mechanical obstruction (hairs)

neoplasia limiting aeration

chronic inflammatory changes (calcification and thickening)

Question 6

what types of neoplasia can affect the ear canals?

Answer 6

squamous cell carcinoma
basal cell carcinoma

melanoma

ceruminous gland adenoma/adenocarcinoma

Question 7

what are the ceruminous glands?

Answer 7

glands which help produce wax/protect ear

Question 8

what is the most common skin tumour in dogs and cats?

Answer 8

basal cell carcinoma - normally benign but can grow quickly

Question 9

what types of middle ear disease are seen in dogs?

Answer 9

bacterial otitis media (alongside chronic otitis externa)

tympanic membrane trauma allowing bacterial infection

rarely tumours unless extension of another tumour

Question 10

what middle ear conditions are seen in cats?

Answer 10

otitis media without otitis externa

neoplasia (rare)

polyps - pharyngeal and external ear canal (unknown aetiology)

Question 11

what are the 3 different presentations of polyps?

Answer 11

only in bulla

protruding through tympanic membrane causing concurrent otitis externa

nasopharyngeal - growing from eustachian tube

Question 12

how can we treat/manage damage to the pinnae?

Answer 12

treat underlying cause (esp if haematoma - suction and drainage, massage, flushing)

full clip of pinna
lateral recumbency
bandaging to immobilise pinna?
buster collar

Question 13

how can we treat invasive pinna neoplasia?

Answer 13

pinnectomy - full removal of pinna

high blood supply - bipolar cautery/ligation required

Question 14

what is involved in a lateral wall resection surgery?

Answer 14

removal of secretory epithelium and lateral cartilage of vertical canal

increases ventilation and drainage of ear

rarely curative

Question 15

when might a lateral wall resection be considered?

Answer 15

patients not responding to treatment

external canal disease

early treatment - before stenosis

Question 16

what is a vertical canal ablation surgery?

Answer 16

excision of whole auricular cartilage and formation of a stoma at the level of the horizontal canal

Question 17

when might a vertical canal ablation be performed?

Answer 17

when there is a disease affecting the entire vertical canal but not he horizontal canal
neoplasia

Question 18

what is a TECA-LBO?

Answer 18

(total ear canal ablation and lateral bulla osteotomy)

removal of all epithelial lining and vertical and horizontal canal cartilages

Question 19

when might a TECA-LBO be carried out?

Answer 19

treatment of chronic otitis externa - unresponsive to medical treatment

trauma
neoplasia

most common surgical procedure on ear in dogs

Question 20

how do you prep a dog for TECA-LBO?

Answer 20

clip entire pinna, face up to caudal border of eyelid and lateral side of neck
prep entire pinna
will need to support pinna during prep

Question 21

what are the potential complications of TECA-LBO?

Answer 21

haemorrhage

infection (+ wound dehiscence)

iatrogenic facial nerve injury/paralysis

vestibular problems

trauma to deeper vessels (lingual/maxillary vessels, hypoglossal nerve)

horners syndrome (self limiting)

fistula formation

Question 22

when might a ventral bulla osteotomy be performed?

Answer 22

reserved for cats with isolated middle ear disease

commonly for treating polyps

Question 23

what are the potential complications of a ventral bulla osteotomy?

Answer 23

horners syndrome
vestibular disease
haemorrhage
infection