Ears and oral surgery Flashcards
Which nerves and arteries are important to consider when attempting auricular surgery?
-> Caudal auricular artery (behind the ear)
-> Maxillary artery
-> Auriculopalpebral branch of facial nerve (runs in close association to the ear - loss of blink reflex if damaged)
-> Facial nerve
-> Sympathetic nerve runs through the tympanic bulla (cats with middle ear disease often have horner’s syndrome because the sympathetic nerve is affected)
What are reasons to consider surgery to the external ear canal?
-> End stage otitis externa
-> Neoplasia
-> Trauma
What is the most common reason for performing a total ear canal ablation and lateral bulla osteotomy?
End stage otitis externa
Is otitis externa a surgical disease?
No! - have to try and do medical management prior to consideration of surgery
Structural changes - mucosal hyperplasia, cartilage thickening/ossification
What neoplasia might be common around/in the ear? And what are the factors to consider for surgery?
Ceruminous gland adenoma/adenocarcinoma
- includes hyperplastic “inflammatory” polyps of the ceruminous gland, slow to metastasise
Squamous cell carcinoma
- locally aggressive, penetrate ear canal
Factors to consider:
- Diagnosis and stage of disease
- Local extend of disease (potential for infiltrative disease beyond ear canal)
- Location of lesion within ear canal
What do we worry about with an animal that has had blunt trauma to the ear?
Avulsion of the external ear canal
- Auricular cartilage at annular cartilage junction
- Entire external ear canal at meatus
So either between vertical canal and horizontal canal or more commonly where the horizontal canal disconnects from the bulla.
How is ear canal avulsion presenting in acute and chronic forms? How do we diagnose?
Acute: swelling
Chronic: fistula
Diagnosis: Otoscopy, fistulogram, CT
A dog presents with an ear canal avulsion where it has avulsed from the bulla - which surgical procedure is recommended?
Total ear canal ablation
A dog present with an ear canal avulsion where only the vertical ear canal is affected - which surgical procedure is recommended?
Vertical ear canal resection
What are the preoperative considerations for ear canal surgery?
-> Contaminated or dirty surgery - perioperative antibiotics
-> Thorough preoperative cleansing!
-> Preoperative treatment - with severe inflammation - aggressive systemic therapy (AB, short course corticosteroids) may substantially reduce inflammation
What are the indications for a vertical ear canal resection?
-> Isolated neoplasia of the proximal vertical canal (no structural changes to horizontal canal)
-> Traumatic avulsion of vertical ear canal
Benefit: a lot of function still retained, dog can still hear
What are the indications for a total ear canal ablation?
-> Severe end-stage otitis externa
-> Neoplasia
-> Trauma
How do you explain to an owner what a total ear canal ablation means anatomically, is hearing still intact?
A total ear canal ablation is a salvage procedure but end of ear canal = end of problem.
Externally the dog will not change and no one will be able to see the dog had a total ear canal ablation.
It will be deaf - the bone conductance is still present as the ossicles will still be there but there is just no air conductance anymore, therefore deaf. In most cases the dogs have been deaf anyway.
When a total ear canal ablation is being performed, which other procedure has to also be performed in combination, because of which anatomical part?
Have to do a lateral bulla osteotomy in combination with a total ear canal ablation because the bulla is often involved
CT scan important!
What are the postoperative considerations after a total ear canal ablation and lateral bulla osteotomy?
-> Place a drain using a vacutainer (change every 2-3 hours), bandage over drain, monitor the drainage
-> Systemic antibiotic therapy - C&S of both ears, 3-4 weeks (osteomyelitis)
-> Monitor/treat facial palsy
-> Histologic examination of of ear canal
Which complications can occur after auricular surgery?
-> Facial palsy
-> cellulitis/drainage, dehiscence, vestibular injury, fistulation, haematoma, fatal haemorrhage
A dog with otitis media associated with otitis externa and a cat with polyp in middle ear - Which surgical procedure is recommended?
Ventral bulla osteotomy
Otopharyngeal polyps - what are they? which animal & age do we see them in?
They are a common cause of otopharyngeal disease in younger cats
Inflammatory polyps originating from middle ear, nasopharynx or eustachian tube.
Clinical features: non-neoplastic masses - inflammatory components: they are well vascularised fibrous connective tissue (inflammatory cells present).
Suspected that it is related to calici, coronavirus or herpesvirus infections.
What are the clinical signs of nasopharyngeal obstruction?
-> Chronic nasal discharge
-> Sneezing
-> Gagging
-> Stertorous breathing
What are the clinical signs of middle ear disease?
-> Head tilt
-> Nystagmus
-> Horner’s Syndrome