What are indications for lateral ear canal resection?
- chronic recurrent otitis externa with NO middle ear disease
- environmental causes (moisture, etc)
- failed appropriate medical management
What is the goal of lateral ear canal resection?
improved air flow and light exposure
Lateral ear canal resection still requires ____________ to be successful in preventing the need for TECA or vertical canal ablation.
client compliance to maintain horizontal canal
Do not perform a lateral ear canal resection in patients with... (2)
- middle ear disease
- hyperplastic ear disease
Describe the clipping margins for lateral ear canal resection.
- lateral canthus of eye
- prescapular area
- dorsal to ventral midline
- clip pinna and ear canal
With lateral ear canal resection, parallel skin incisions are made from proximal to distal from the...
tragohelicine incisure and intratragic incisure--> extending to the base of the vertical ear canal (palpated)
Exicision of the lateral aspect of the vertical canal is performed with ___________.
serrated mayo scissors
When performing a lateral ear canal resection, it is critical to removed the ____________.
lateral 180 degrees of the vertical canal
Describe the closure of lateral ear canal resection.
- primary closure of ear cartilage to skin (so it takes longer to heal)
- non-absorbable monofilament 3-0 or 4-0 (nylon, prolene, novafil)
What are potential complications with lateral ear canal resection? (4)
- wound dehiscence
- stenosis of horizontal canal
- persistent otitis externa
- hyperplastic proliferation of the remaining ear canal (don't do this sx in american cocker spaniels because they all end up needing TECA eventually)
Describe the parotid salivary gland.
- flat V-shaped gland caudal to the TMJ and lies over the ventral aspect of the vertical ear canal
- monostomatic gland
- serous secretion
- duct lies on ventral 1/3 of the masseter muscle and opens lateral to upper 4th premolar
Describe the mandibular salivary gland.
- compact encapsulated gland at the bifurcation of the external jugular vein
- mucoserous secretion
- duct courses medial to ramus and opens at the lateral base of the lingual frenulum
Describe the sublingual salivary gland.
- in close anatomical associated with the mandibular gland and they share a common capsule
- monostomatic and polystomatic
- mucoserous secretions
- drains to the major sublingual duct either caudal to mandibular orifice or in some dogs it shares an opening with the mandibular gland
Describe the zygomatic salivary gland.
- situated at the base of the orbit (deep and rostral to zygomatic arch)
What are potential locations of salivary mucocele? (4)
- cervical salivary mucocele (most common)
- base of tongue (lateral to frenulum)
- pharyngeal wall
- periorbital facial swelling
What are possible etiologies of salivary mucocele? (4)
- most unknown
- congenital malformation of duct or gland/ duct junction
- obstructive disease (inflammation, fibrosis, stenosis, sialoliths)
Salivary mucoceles almost always form from...
leakage of the polystomatic openings of the sublingual salivary gland (but we also remove the mandibular gland because they are associated in the same capsule)
What are clinical signs of salivary mucocele? (4)
- visible soft tissue swelling (fluid filled)
- may fluctuate in size
- recurs after drainage
What is rannula?
if ducts rupture under tongue
What is the treatment for salivary mucocele?
excision of the sublingual salivary gland (monostomatic and polystomatic) and the mandibular salivary gland (b/c they are associated in the same fibrous capsule)
Where do you make the incision for the lateral approach to salivary gland excision?
incise skin and SQ from the angle of the jaw over the bifurcation of the jugular vein
What is important when dissection out the mandibular/ sublingual salivary glands?
- remove as much polystomatic gland as possible (to prevent recurrence and rannula)
- dissect bluntly until you see the facial artery, vein, and lingual branch of the trigeminal nerve
- disrupt the salivary gland with traction (do not cut)
After salivary gland removal, it is important to...
bandage head and neck for 5-7 days to keep it compressed
What are potential complications wth salivary gland excision? (5)
- operated on the wrong side
- did not remove enough polystomatic portion of sublingual gland
- removal of mandibular lymph node instead of salivary gland