Surgical Conditions of The Ear Flashcards
what are the main conditions affecting the pinnae?
trauma - lacerations
aural haematoma
neoplasia
what causes aural haematoma?
head shaking causing bleeding between the skin of the ear and the cartilage
when does aural haematoma arise?
usually secondary to other conditions which are causing the dog to shake it’s head
what are the 2 main types of neoplasia seen on the pinna?
squamous cell carcinoma
melanoma
what animals are more prone to neoplasia of the pinna?
white haired
hairless
unpigmented skin
what can be used to protect at risk skin on the pinna from neoplasia?
high factor childs sun cream
what makes up the external ear canal?
vertical and horizontal canals
what is otitis externa?
dermatological disease affecting the ear
what is the most common infection in dogs?
otitis externa
what are the main causes of otitis externa?
immune mediated (allergic)
parasitic infection
poor aeration due to conformation
seconday to middle ear infection (cats)
what is the name of the ear mite of dogs, cats, rabbits and ferrets?
otodectes cynotis
how can poor aeration of the ears be caused and lead to otitis externa?
floppy ears
mechanical obstruction (hair/FB)
neoplasia
chronic inflammatory changes due to previous otitis externa leading to calcification and thickening
when is otitis externa seen in cats?
secondary to middle ear problems
what is the most common condition of the ears in cats?
middle ear issues
what are the main types of neoplasia which affect the ear canals?
squamous cell carcinoma
melanoma
basal cell carcinoma
ceruminous gland adenoma (benign) or adenocarcinoma (malignant)
what is the survival rate for squamous cell carcinoma of the ear canal?
at least one year after surgery
why is squamous cell carcinoma invasive?
may metastasize
if multi centeric further lesions can appear after removal
where is the ceruminous gland found?
sub-dermal layers of the ear canal
what is the role of the ceruminous gland?
helps produce wax
protects ear
what is the issue with melanoma?
more deadly as spreads quickly
what is the most common skin tumor in dogs and cats?
basal cell carcinoma
how severe is basal cell carcinoma?
normally benign but can grow quickly
what are the main middle ear diseases of dogs?
bacterial otitis media
tympanic membrane trauma allowing bacterial infection
tumors are rare unless an extension of another tumor
what is otitis media?
inflammation in the middle ear
what is bacterial otitis media most often caused by in dogs?
development of chronic otitis externa
what are the most common middle ear diseases in cats?
otitis media without otitis externa
neoplasia (rare)
polyps
what is otitis externa in cats normally due to?
primary middle ear disease
what is the most common mass diagnosed in cats?
polyps
what are the areas in cats affected by polyps?
pharyngeal
external ear canal
what causes polyps in cats?
unknown aetiology
what are the 3 common presentations of polyps?
only in bulla (middle ear)
protruding through tympanic membrane
nasopharyngeal
what is caused by polyps protruding through tympanic membrane?
concurrent otitis externa
where do nasopharyngeal polyps grow from?
eustachian tube
what is involved in the surgical treatment of all issues with the pinnae?
treatment of underlying case
what lacerations will be treated surgically?
full thickness lacerations or epithelium torn away from cartilage
what must be considered about ear lacerations?
need for flushing as there is infection risk
why does cartilage take longer to heal?
poor blood supply
what is the purpose of surgical correction of auricular haematoma?
prevent further accumulation and deformity
allow fibrosis of the skin and cartialge
how can an aural haematoma be prevented from reforming after drainage?
use correctly placed sutures to hold skin and cartilage together
what is involved in correction of auricular haematoma?
suction and drainage
massage and flush
can auricular haematoma resolve without treatment?
yes in some cases
what surgical prep is needed for auricular haematoma?
full clip of pinna
what positioning is required for auricular haematoma surgery?
lateral recumbancy
what post of care is needed for the auricular haematoma patient?
bandaging to immobilise pinna
buster collar
what is the issue with ear bandages?
affect ventilation of ear canal and so can lead to otitis externa
when performing pinna neoplasia surgery what must be considered?
site
size
histology needed and so pot size
what is pinnectomy?
full removal of pinnae
what is pinnectomy used for?
removal of invasive tumors
what is a significant side effect of pinnectomy?
bleed profusely so bipolar cautery needed for haemostasis
what is removed during a lateral wall resection?
secretory epithelium of vertical canal
lateral cartilage of vertical canal
in what animals is lateral wall resection used?
chronic OE
patients not responding to treatment
external canal disease
when must lateral wall resection be performed?
early before any stenosis (thickening)
what is the purpose of a lateral wall resection?
increases drainage and ventilation
what is required post lateral wall resection?
medical management as non-curative
what clip is needed for lateral wall resection?
entire pinna and side of head
what should be done prior to lateral wall resection prep?
flush ear to remove debris
what position should animals be in for lateral wall resection?
lateral recumbency
head elevated
what is involved in a vertical canal ablation?
excision of whole auricular cartilage and formation of a stoma at the level of the horizontal canal
what is vertical canal ablation used to treat?
disease affecting the entire vertical canal but not the horizontal
e.g. neoplasia
what may be needed in vertical canal ablation?
histology samples
how is the patient prepped for vertical canal ablation/
as for lateral wall resection
what is the most common procedure performed on the ear in dogs?
total ear canal ablation (TECA)
when is a TECA performed on cats?
alongside lateral bulla osteotomy (LBO)
what is TECA and TECA-LBO used to treat?
chronic otitis externa that is unresponsive to medical treatment
trauma
neoplasia
what happens during TECA-LBO?
removal of all epithelial lining and vertical and horizontal canal cartilages
what are the potential serious complications associated with TECA-LBO?
neurological - facial nerve paralysis and hearing loss
infection
cosmetic
what is essential when conversing with owners about facial surgery?
prepare them for what their animal may look like
meeting with owners who have had experience
never let owners take a cat home without taking them out and showing them the surgical area
how should patients be prepped for TECA-LBO?
clip entire pinna, caudal boarder of eyelid and lateral side of neck
prep entire pinna
what will need to be done throughout TECA-LBO prep?
pinna supported with towel clamp so it is held out of the way
how can hair be prevented from falling in the ear canal during clipping for surgery?
plug ear
what are the complications associated with TECA?
haemorrhage iatrogenic facial nerve injury vestibular problems trauma to deeper structures facial nerve paralysis Horner's syndrome infection fistula formation cholesteatoma
why is haemorrhage likely in TECA surgery?
limited visualisation
how can haemorrhage be prevented in TECA?
cautery
swabbing
suction
(scrub nurse role)
what deeper structures may be injured following TECA?
lingual / maxillary vessels
hypoglossal nerve
what TECA complications are often self limiting?
facial nerve paralysis
Horner’s syndrome
what is the most common TECA complication?
infection
what can infection lead to?
wound dehiscence
what is cholesteatoma?
keratinising epithelium that has been left behind by the surgeon that must be removed
in what animals is a ventral bulla osteotomy performed?
cats with middle ear disease
why is ventral bulla ostotomy not often performed in dogs?
rare for dogs to have isolated middle ear diease
what is ventral bulla osteotomy useful to treat?
middle ear polyps
what are the complications of ventral bulla osteotomy?
Horner’s syndrome
vestibular disease
haemorrhage
infection
why is communication with the owner of a surgical ear patient vital?
complications are common and frustrating to manage
informed owner will be more understanding if complications do occur
what is the role of the VN in surgical ear conditions?
prep of patient
intra-operative support
counseling of owners with VS
post op care and observations
