32. surgery for ear disease

what causes aural hematomas?

secondary to trauma from ear disease

• shear forces → dead space, fills with blood

  • violent head shaking, ear scratching

• ALWAYS do a thorough ear exam → must treat underlying disease

outcomes of doing nothing to treat aural hematoma

• clot granulates

• cavity fibroses, cartilage ossifies

• disfigurement ± chronic irritation

aural hematoma treatment — drain ± steroids

• drain only

  • clip & prep in sterile fashion!

  • least effective treatment; typically recurs, multiple treatments

  • can introduce infection to the site

• + steroids

  • conflicting results; will likely require multiple treatments

what type of surgical drain is preferred for aural hematomas? which are not?

• preferred → closed suction drain

• penrose drain (not recommended)

• teat cannula (messy everywhere)

aural hematoma treatment — incision drainage

• can use 1st line; definitely for chronic, severe, or recurrent cases

• S-shaped incision through skin

• remove clot and fibrin, flush

• place large, full-thickness, non-resorbable, interrupted mattress sutures over entire convex surface of pinna

  • MUST be parallel to vasculature

• ear ends up thickened

aural hematoma — post-op care & complications

• need to bandage ear (compression)

  • fold ear onto dorsum of head

  • change every 2-3 days until skin adhering down

• treat underlying cause

• complications

  • infection

  • recurrence

what is the most common neoplasia of the pinna?

• squamous cell carcinoma in cats (sunny climates)

  • white cats have increased risk

  • tend not to spread if only on pinna

• other tumors are possible

  • hemangioma/hemangiosarcoma

  • basal cell tumors, mast cell tumors, histiocytomas, etc.

pinna neoplasia — diagnosis

FNA or incisional biopsy

• staging dependent on tumor type

pinna neoplasia — treatment

subtotal or total pinnectomy

• amputate pinna at least 1-2 cm from tumor

• cauterize vessels

• pull skin on concave surface over cut edge and suture

  • don’t suture cartilage

diagnostic work up for diseases of the ear canal / bulla

• otoscopy: should be done on every animal presenting for ear disease (+ routine exam)

• palpation: is ear canal ossified? (indicates end stage disease)

• otic cytology and biopsy (try to obtain from horizontal canal)

• FNA, biopsy, impression smear if mass seen in canal

• diagnostic imaging: CT ideal

how is the bulla anatomically different in dogs vs. cats?

septum of the tympanic bulla is present in dogs & cats, but separates bulla into 2 compartments in cats (communicate medially through a slit-like opening)

what is the most common ear canal neoplasia?

ceruminous gland adenocarcinoma

indications for TECA / TECABO surgery

• severe, irreversible chronic obstructive ear disease (end stage disease)

  • calcification of ear canals

  • patency of ear canals minimal or absent

• neoplasia of the ear canals that extend into the horizontal canal or beyond

post-op complications of TECA surgery

• bleeding (retroglenoid/retroarticular vein)

  • can be life-threatening

• facial nerve paralysis or paresis

• horner’s syndrome

  • cats > dogs due to anatomic location of post-ganglionic sympathetic fibers

• post-op fistula

  • can occur if epithelium left in bulla, ear canal not completely removed, or debris left behind

  • draining sinuses may not appear for months to years

• warn owners that dogs will technically be deaf after surgery

where do feline polyps originate?

• within auditory tube → usually grow into nasopharynx

• from rostral lateral (smaller) compartment of the tympanic bulla → usually grow out the ear canal

• can grow in both directions

feline polyps — diagnosis

• CBC, chem, UA, FeLV/FIV testing

• under general anesthesia

  • examine ears

  • evaluation of pharynx via rostral reaction of the soft palate or with a scope

  • CT scan

feline polyps — removal via traction + medical treatment

• steady traction can be applied to polyps for removal

• can occur via oral cavity or ear, depending on location

• medical treatment

  • antibiotics: base on culture if associated with ear infection, otherwise broad spectrum

  • prednisolone (typically 2 wks)

  • analgesics for 4+ days (e.g. buprenorphine)

indications for VBO surgery

• most commonly done in cats for polyps originating in the middle ear

  • usually try traction 1st

  • gives access only to middle ear

• also undertaken in cases of severe middle ear infections where ear canal is still patent (dogs & cats)

• rarely done in dogs; also much more challenging due to location of bulla

feline polyps — post-op complications / prognosis

• horner’s syndrome

  • often resolves within weeks; if still around at 6 wks, likely permanent

• vestibular signs (can occur with TECAs as well)

  • many pre-date surgery due to pressure on labyrinthine structures from material in ear

  • iatrogenic: can occur from either osteotomy or curettage during polyp removal

• unlike TECA, facial nerve paralysis is uncommon