Ear disease and surgery

Question 1

What are the two parts of the tympanic membrane

Answer 1

Pars tensa = thin, clear bit we see
Pars flaccida = dorsal part which can bulge downwards if fluid accumulates in middle ear and be mistaken for ear neoplasia

Question 2

What is erythroceruminous otitis

Answer 2

Most common form of otitis
See redness with yellow/brown ceruminous discharge
Pruritic; not really painful
Staphs on cytology +/- malassezia

Question 3

What organisms is suppurative otitis assocaited wtih

Answer 3

Pseudomonas, proteus and other gram -ves

Question 4

What does a cobblestone appearance of ear suggest

Answer 4

Chronic pathological changes due to poorly managed ear disease over month s
= hyperplasia of ceruminous glands, thickebing of dermis and epidermis causing canal stenosis
Chronic fibrosis

Question 5

When do we do cytology or C/S in ear disease

Answer 5

Always cytology
Culture and sensitivity sometimes; but not that useful because antibiotic ocnentrations very different in ear compared to in vitro prediction s

Question 6

What is the primary cause in 80% of ear disease

Answer 6

Atopic dermatitis

Question 7

Which animals get otodectes
What to remember
How to treat

Answer 7

Esp puppies/kittens
Treat with selemectin or canaural
Remember it is zoonotic potentially

Question 8

What endocrine disease can be implicated as a primary cause of ear disease

Answer 8

Hypothyroidism due to altering

Question 9

What neoplasia can be a primary cause of ear disease

Answer 9

Ceruminous cystomatosis which is non-neoplastic; can progress to adenocarcinoma

Question 10

What considerations must we have before applying otic polypharmaceutical

Answer 10

Ask owner to turn head away since these are ototoxic
Tympanic membrane may be ruptured; not meant to use

Question 11

What medications can be ototoxic

Answer 11

All can be
Esp aminoglycosides, cisplatin, furosemide

Question 12

What antibiotics have lower ototoxic potential so good to go for

Answer 12

Fluoroquinolones, ceftazidime (cephalosporin)

Question 13

What cleaning product is good to use in ear due to low ototoxic potential

Answer 13

Triz EDTA
Can be an antibacterial glush and potentiate antibitoic activity
Good against pseudomonas

Neutralising solution e.g between low pH ear cleaner and antibiotics

Question 14

Options for assessing integrity of tympanic membrane

Answer 14

Visual assessment; not very accurate
Spruells neede; if hit bone = bulla so not bouncing on trampoline of tympanum
Advanced imaging
POsitive contrast canalograpu pst semsotove

None are 100% accurate

Question 15

WHat is the blood supply to the ear like

Answer 15

Large supply via auricular arteries off the carotid

Question 16

Pathogenesis of aural haematmooa

Answer 16

Head shaking due to otitis externa or parasitic infection leads to damage to blood vessels, cartilage fracture and fluid leakage ot form haematoma

Question 17

Treating acute haematoma aural

Answer 17

Needle drain +/- corticosteroid injectino
Must recurrence common

Question 18

How to treat chronic aural haemotoma

Answer 18

Need an incisional drainage surgery to remove dead space and provide drainage

Involves placing non-absorbable mattress suture full thickness sutures to take the skin down to the cartilage
- Keep in place for 2 weeks
- Can use stents to present sutures being placed too tightly

Question 19

What is actinic keratosis

Answer 19

Pre-neoplastic change for aural SCC

Question 20

Treatment options for aural SCC

Answer 20

Surgical excision with 1-2 cm margins
Pinnectomy may be needed to achieve this

Question 21

What cartilages do the vertical vs horizontal ear canal involve

Answer 21

Vertical = auricular
Horizontal = annular

Question 22

Difference in bulla between dogs and cats

Answer 22

In dogs, single, small cavity not externally palpable
Cats: larger bulla with incomplete bony septum splitting bulla into small dorsolateral compartment and large ventromedial comparmtnet
Symp nerves more exposed in cat

Question 23

What structures msut we be aware of during ear surgery

Answer 23

Facial nerve; passes outside bony skull ventral to ear canal
Retroauricular vein
Parotid salivary gland

Question 24

How commonly are ear canal neoplasias malignant in dogs/cats

Answer 24

Cats; 90% malignant
Dogs; 60%

Question 25

What breeds ar eprone to otitis externa

Answer 25

Dogs with floppy ears e.g cockers
Dogs with stenotic ear canal e.g brachycephalics

Question 26

What imaging can se use to diagnose otitis exerna/middle ear disease

Answer 26

CT or MRI best
Used to use 30* rostroventral-caudodorsal open mouth view for tympanic bullae

Question 27

What are the 3 surgical options for ear disease if not responsive to medical management or neoplasia

Answer 27

Lateral wall resection
Ventral canal ablation
TECA-LBO

Question 28

Indications and contra-indications for lateral wall resection

Answer 28

Indications:
* Removal of benign polyps/small neoplasms in vertical canal
* Congenital vertical canal stenosis in shar pei
* Mild-moderate otitis external WITHOUT any middle ear disease, horizontal canal involvement or irreversible hyperplastic disease

DO NOT DO IN COCKER SPANIELS AS HIGH FAILURE RATE

Question 29

How does lateral wall resection surgery work

Answer 29

Provides increased drainage and ventilation to ear canals to improve local microenvironments

Via removing some of vertical circumference and creating new drainage board ventral to junction with horizontal canal to allow secretions out

Question 30

What is a vertical canal ablation and what re the indications

Answer 30

Removal of entire vertical canal and create new opening into horizontal canal
* Use for ear disease limited to vertical canal (which is rare)
Need meical management after

Question 31

Indicatinos for total ear canal ablation and bulla osteotomy

Answer 31

Chronic end stage otititis externa
Recurrent otitis media/externa
Neoplasia
Persistent pseudomonas infectino
Poor compliance
Poor quality if life
Failure of prevoius surgeries

Question 32

What must we do during LBO to prevent post-op complications

Answer 32

In cats do ventrally below shelf to access both compartments of bulla for debridement inside
Remove entire secretory lining of the bulla and external ear canal to avoid complications

Question 33

What are some short and long term complications of TECA_LBO

Answer 33

short term: wound infection, seroma formation, temporary facial nerve paralysis

Long term; all go deaf
Permanent facial nerve paraysis, vesitbular injury (but animals tend to adjust over time), chronic fistula or abscess formation which may need repeat surgery

Question 34

How to deal with facial nerve paralysis from TECA-LBO

Answer 34

Use ocular lubricants
Usually temporary

Question 35

When might we do a ventral bulla osteotomy

Answer 35

Removal of inflammatory polyps in cats
Primary otitis media
BUlla neoplasia
Exploration of abscesses formation after previous TECA-LBO

Question 36

How do feline inflammatory polyps present and what are the teatment optins

Answer 36

Young cats
SNeezing, nasal/aural discharge
= non-neoplastic masses coming from mucosal lining of nasopharynx/auditory tube or tympaic bulla

Conservative treatment = traction avulsion +/- steroids but often recur

Surgery (ventral bulla osteotomy) indicated if neurosigns present or conservative treatment failued

Question 37

Which breeds can get sterile primary otitis media

Answer 37

CKCS
BRachy

Question 38

What are the advantages of VBO over LBO

Answer 38

VBO allows access to both bulla (but this can give unnacceptably high complication rtes)
better bulla exposure
Reduced risk of facial nerve damage