Ear surgery Flashcards
Major indications for ear surgery
§ 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
Aural haematoma tx
§ Surgical incision, drainage, and suture
§ Drainage with an indwelling drain (Penrose, tube, teat tube, etc.)
§ Drainage and glucocorticoid instillation
§ Closed-suction drainage
§ If you don’t deal with the underlying problem that’s making them itchy/head skate it rarely resolves
Aural haematoma - incision, drainage & suture
- Probs most effective way of dealing with it is making an incision, leaving it open, tack down the surface around this incision whilst it heals
- Then get a granulation band and scar tissue which means it wont reform again
- Drip tubing can be used along the long axis of the pinna (parallel to the incision) to help the sutures stay taught and not bunch up or loosen.
Aural haematoma - skin punch
- Using a punch biopsy to make multiple holes and then taking each one down
- takes a long time
Aural haematoma - teat tube or surgical drain
- Don’t have the compression aspect so the drain will need to stay in for longer
- probs more problematic to manage.
Aural haematoma surgery – complications
- Cosmetic alterations
– consequences to show career - Recurrence of haematoma
- Pinna necrosis
Surgical procedures of the external ear canal
- Lateral wall resection (LWR)
- Vertical canal ablation (VCA)
LWR indications
- 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
Historically was done to try and improve the drainage of the external ear canal and change the microenvironment of the horizontal ear canal - with the assumption that it would be enough to manage a case of chronic external ear dz, but now know that it’s not going to deal with the underlying cause of the ear dz (e.g. allergic dz in atopic dz or food hypersensitivity) and so it will persist. Now restricted to neoplasia of the lateral wall of the vertical canal.
What does a LWR do?
- does not cure the animal of its underlying disease but improves the micro-environment of the ear
Reasons why LWR can fail
- if there are chronic, irreversible, hyperplastic changes to the luminal epithelium or if there is ongoing otic inflammation
Complications of LWR
- Postoperative pain/discomfort
- Incisional dehiscence
– dirty site and infection quite likely - Persistent otitis externa
- Persistent, unrecognised otitis media
- Failure to provide adequate drainage of the horizontal canal
- If not done properly can get stenosis of the horizontal canal
Vertical canal ablation - indications
- Only rarely indicated
- Vertical canal only is diseased
- Neoplastic disease and polyps restricted to the vertical ear canal
Vertical canal ablation – complications
- Postoperative pain/discomfort
- Incisional dehiscence
- Persistent otitis externa
- Persistent, unrecognised otitis media
- Stenosis of horizontal canal
Surgical management of chronic otitis externa / otitis media
- Total ear canal ablation and lateral bulla osteotomy (LBO)
- Ventral bulla osteotomy (VBO)
For chronic dz or end stages do a total ear canal ablation + bulla osteotomy - have to combine it with a bulla osteotomy as you cant take out the entire ear canal and get rid of the portion that’s within the bony part of the skull (before you reach the tympanic membrane) without removing a small portion of the bulla.
Another term for chronic otitis externa & explanation of how it can get to this stage
- ‘end-stage’ ear
Chronic medical management of ear dz that has been ineffectual either bc not done appropriately or despite being done appropriately the dz is too advanced and can’t be managed effectively. Get pathological changes which means the canal becomes very narrow and is difficult to manage. Can’t medicate it properly. Pathological changes are irreversible. From a surgical POV = end stage ear.
Conventional radiography
- Open mouth bulla radiograph
- Trying to get a skyline view of the bulla.
- Will be some superimposition bc of the spine.
- Trying to see if they’re air filled and black - pneumatised
- Compare 1 to other
– see if any sclerosis (increased whitening and thickening of the bone).
Computed tomography (CT)
- same as radiography basically
- but more detail
- and more 3D like view
Total ear canal ablation – bulla osteotomy (TECA BO) indications
- 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
Complications of TECA BO
- Postoperative pain/discomfort
- Deafness
- Incisional dehiscence
- Facial nerve paralysis
- Vestibular disturbances
- Haemorrhage
- Horner’s syndrome
- Recurrence/abscess formation
Classic features of Horner’s syndrome
- Anisocoria with ipsilateral miosis
- Ptosis of the upper eyelid
- Narrowing of the palpebral fissure
- Enophthalmos
- Protrusion of the third eyelid
Ventral bulla osteotomy (VBO) indications
- in cases with middle ear disease and the following circumstances:
- Cases in which a TECA is not required
- Certain brachycephalic breeds of dog
- bc of the skull shape the bulla is very small
- The vertical ramus of the mandible means that getting the lateral approach to the bulla is very difficult
- So with brachys need to do total ear canal ablation then if dz in the bulla do a ventral approach.
- Often used in the cat
– anatomy of the bulla (i.e. easer to get into the 2 compartments this way vs going laterally)
– inflammatory polypoid disease in the absence of chronic otitis externa
Complications of VBO
- Postoperative pain/discomfort
- Deafness
- Incisional dehiscence
- Facial nerve paralysis
- Vestibular disturbances
- Haemorrhage
- Horner’s syndrome
- Recurrence/abscess formation
Cholesteatoma - what is this?
- 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. - Look like a rapidly growing expansile tumour.
- Expansile lesion that has mineralisation and bone formation on time - looks like it has exploded out of the inner ear on the affected side.
- See it in dogs, not very commonly.
- Rarely see in cats.
Cholesteatoma - tx
- TECA BO or VBO
– but terrible area to operate on bc of all the nerves and blood vessels and structures - All the cranial nerves are around this area so you have very poor access and a very limited safety window, so you’re changes of removing all of it slim due to risk of causing more damage by trying to remove it all.
- Also usually by the time you find them they’re super advanced and too difficult to perform on anyway.
