Flashcards in Ear surgery Deck (57)
What attaches ear cartilage to the head medially?
What artery supplies the pinna?
great auricular artery
What is the tragus?
a small, pointed eminence of the external ear
Define aural haematoma
collection of blood within the cartilage plate of ear from damage to branches of great auricular artery. cause unknown, probably trauma to pinna, usually produces a swelling on concave surface of ear
CAuses - aural haematoma
- Predisposing factors = headshaking, ear scratching
- Underlying causes = aural inflammation, parasites, allergy, FB
Outline possible progression of aural haematoma
Haematoma --> seroma --> fibrosis --> contraction deformity
Tx aims - aural haematoma
- address underlying source of irritation
- evacuate haematoma
- prevent recurrence
Conservative management - aural haematoma
- needle aspiration (+/- corticosteroid injection) = high recurrence rate
- pressure bandage, difficult to apply well
- continuous drainage through a canula, penrose or closed suction drain for 2-3 weeks
Surgical management - aural haematoma
- incise concave pinna (linear, ovoid, S or X shaped)
- evacuate haematoma
- appose cartilage with sutures (place vertically so parallel to major vessels, minimise tension. place through cartilage and one or both skin surfaces)
- don't suture incision (leave open for drainage)
- light bandage for several days
- remove sutures at 10-14 days.
What is amputation of the pinna called?
Indications - pinnectomy
- solar injury (white cats especially)
- cold injury (uncommon)
- permanent marking (ferals)
Outline method for pinnectomy
Try to excise with 1cm of normal margins if treating neoplasia, submit for histopath, close by primary apposition of skin edges over amputated cartilage.
What do you need to decide for external and middle ear disease?
1.) if or when surgical tx is necessary
2.) if it is what type of surgical procedure is appropriate
CS - middle ear disease
- head shake
- tilt/ rotate head (to affected side)
- self-trauma (aural haematoma)
CS - inner ear disease
- as for OM
- poss damage to vestibular and auditory structures and nn (problems with balance, coordination, circling, head tilt, nystagmus, hearing loss. CNS signs if infection extends into CNS).
Key features of an aural exam
- if ear disease is painful/ advanced perform under sedation/ GA
- suction of a blocked ear canal allows proper assessment
- how stenosed or disesed are the vertical and horizontal canals
- state of the TM
- mass visible?
Outline ear radiography
- requires GA
- 3 views (DV skull, open-mouth bullae, lateral oblique bullae)
- evidence of ear canal stenosis, calcifications?
- evidence of middle ear disease (normal bulla has thin walls and contains air)
- chest radiographs if neoplasia suspected
T/F: normal radiographs rule out middle ear disease
False - normal radiographs DON'T rule out middle ear disease
what are the 3 parts of the external ear canal?
- vertical (auricular cartilage)
- horizontal (annular cartilage)
- vertical and horizontal canals joined by annular ligament
What lines external ear canal?
strat. sq. epithelium (to tympanic bulla)
Where do the facial nerve exit?
stylomastoid formen (caudal to ear) and runs ventrolateral in close proximity to the base of the external ear canal/ middle ear cavity
CS - facial nn damage
- inability to blink
- lip droop (look for facial symmetry)
- dry eye (inadequate tears)
What sx may be useful in repeat otitis externa?
lateral wall resection
Tx - endstage otitis externa (usually with concurrent OM)
TECA = total ear canal ablation
LBO = lateral bulla osteotomy
Aim of lateral wall resection (LWR)
- increase drainage and ventilation of ext. ear canal
- decrease moisture, humidity and temp.
Indications - lateral wall resection
OE that hasn't responded OR has recurred despite appropriate medical management
Contra-indications - lateral wall resection
- chronic, endstage OE
- irreversible horizontal canal disease/ stenosis
Describe surgical technique for lateral wall resection
- clean ear - clip widely - lateral recumbency - sandbag under neck - make vertical parallel skin incision from tragic notches ventrally - connect skin incisions ventrally and reflect skin flap dorsally - stay close to lateral cartilage of ear canal - void parotid gland - incise cartilage of lateral ear canal in two parallel vertical cuts from annular ligament to intra- and pre-tragic notches - reflect cartilage ventrally and remove excess cartilage to form a 'baffle plate' hinged about annular ligament - suture cartilage to skin epithelium (interrupted) - always place a buster collar - remove sutures at 10- 14 days
Complications - lateral wall resection
- disease recurrence
- wound breakdown
- wound infection