SA Oropharyngeal & Nasopharyngeal Surgery

Question 1

1. What is an oronasal fistula?
2. Breed disposition for oronasal fistulae?

Answer 1

1. Abnormal hole or orifice between the oral and nasal cavities.
   Can be either congenital or acquired.
2. Brachycephalic patients e.g. brachycephalic dogs, Persian cats.

Question 2

Congenital oronasal fistulae clinical signs.

Answer 2

Facial deformity.
Respiratory signs e.g. coughing, gagging when drinking (aspiration pneumonia).
Failure to thrive.
Can be no clinical signs at all.

Question 3

Congenital oronasal fistulae diagnosis?

Answer 3

Clinical exam.
- assess face.
- assess in mouth – hard and soft palate.
–> primary palate defect = front of palate / facial component.
–> secondary palate defect = hard palate and further back e.g. soft palate
–> combined defect = both 1’ and 2’.
Imaging only required if suspect 2’ problem e.g. aspiration pneumonia.

Question 4

Importance of a functional and normal palate.

Answer 4

Ability to suck to ingest milk.
- create vacuum.
Abnormality causes inability to create vacuum so inability to suck and ingest milk.
- milk out of nose or down trachea – get pneumonia.

Question 5

Congenital oronasal fistulae aetiology.

Answer 5

HEREDITARY.

nutritional
viral.
toxic.
trauma.

Question 6

Congenital oronasal fistulae Tx.

Answer 6

Timing is important.
- neonates need to obtain nutrients to develop and survive.
Not good surgical candidates due to small size. - try to delay until bigger – depends on breed.
Support while wait for surgery:
- bottle feeding, tube feeding.
Once big enough, reconstructive surgery to form a more normal barrier between nose and mouth to allow vacuum and suction to allow normal feeding.
- For primary, reconstruct w/ local skin flaps.
– complicated and prone to breakdown.
- For secondary, reconstruct w/ local mucosa flaps – also complicated.
– can do w/ single layers, double layers etc.
PTS is always a treatment option.

Question 7

Acquired oronasal fistulae aetiology.

Answer 7

Trauma:
- impact, malicious.
- iatrogenic e.g. dental procedures.
Severe periodontal disease - often seen in dachs.

Question 8

Acquired oronasal fistulae conservative Tx.

Answer 8

May heal on its own.
Supportive care - adjustments to feeding, foods that can be swallowed cleanly, analgesia, rinsing mouth e.g. w/ Hexarinse, may need an O-tube, avoid chew toys and treats.
Surgery - elevation of mucosa to close the hole, from the palate, or the lip.

Question 9

Oronasal fistulae outcomes.

Answer 9

Dehiscence - at least 50%.
Repeat surgery - have to navigate and debride unhealthy tissue, that is contaminated. Bone may also be infected – may need tissue samples for culture.

Question 10

Nasopharyngeal disorders.

Answer 10

Nasopharyngeal atresia / stenosis (rare).
BOAS.
Nasopharyngeal polyps.

Question 11

Clinical signs of nasopharyngeal disorders.

Answer 11

Upper respiratory tract obstruction.
Stertor.
Mouth breathing.
Sneezing.

Question 12

Nasopharyngeal atresia / stenosis aetiology.

Answer 12

Congenital.
Acquired:
- potential complication of prolonged anaesthesia.
– silently regurgitating and stomach acid stops and sits in nasopharynx –> severe inflammation –> stenosis.
- chronic rhinitis –> chronic inflammation –> stenosis.
- FB causing inflammation for prolonged period.

Question 13

Nasopharyngeal atresia / stenosis Tx.

Answer 13

Surgical resection (rhinotomy) - complex.
Balloon dilation alongside endoscopy.
- can cause more scarring and stenosis as causes inflammation.
Stenting.

Question 14

Nasopharyngeal inflammatory polyp aetiology.

Answer 14

Auditory tube:
- tissue lining auditory tube becomes inflamed, resulting in hyperplasia and secondary changes during mitosis. Growth is benign.

Question 15

1. Inflammatory polyp conservative Tx.
2. Inflammatory polyp surgical Tx.

Answer 15

1. Slow and steady traction w/ crocodile forceps to break polyp off at its base.
   Follow up w/ preds 1-2mg/kg PO.
2. Choice of surgery depends on where we think the polyp has come from.
   Ventral bulla osteotomy - may not remove all polyp as may have formed from auditory tube and recurrence possible.
   Ear canal surgery.

Question 16

Nasopharyngeal inflammatory polyp Px.

Answer 16

Complications:
- of retraction – may leave some behind, recurrence possible.
– bleeding –> usually self-limiting.
- neuro complications – Horner’s syndrome –> sympathetic fibres in the middle ear.
- infection – unusual –> may present w/ otitis externa to start.
90% response rate w/ retraction followed by steroids w/ polyps that pop into the mouth.
50% response rate w/ middle ear polyps.

Question 17

What tissue can be affected w/ oral masses.

Answer 17

Bone: - mandible, maxilla, hard palate, nasal bones.
Soft: - gingiva, mucosa, periodontal ligament, tongue, tonsils.

Higher turnover tissue = increased likelihood of masses - soft tissues more likely than bone.

Question 18

Oral masses clinical signs.

Answer 18

Mass visible in mouth.
Dysphagia, gagging, dropping food.
Irritation and rubbing at the mouth.
Halitosis - food gathers around mass and rots.
Bleeding - can be dramatic w/ involvement of large blood vessels if tumour is erosive.

Question 18

Investigation of oral masses.

Answer 18

Cytology - impression smear of accessible.
– SCC in cat can exfoliate easily, FNA.
Histopathology.
Early staging as can be highly malignant (thoracic radiography for mets).

Question 19

1. Benign oral mass aetiology.
2. Malignant oral masses

Answer 19

1. Inflammatory / immune-mediated / infectious.
   Benign neoplasia.
2. Fibrosarcoma (locally aggressive), melanoma (poor Px) (in dogs).
   Osteosarcoma, odontogenic tumours. Squamous cell carcinoma (in cats) - tend to be on tongue in dogs, and tonsils and further back in cats.

Question 20

Oral mass Tx options.

Answer 20

Surgery:
- local.
- wide - getting sufficient margins can be challenging.
- lymph nodectomy.
Other therapies:
- vac for melanoma in dogs – reasonable successful.
- radiation.
- photodynamic therapy.

Question 21

Complications of oral masses.

Answer 21

Intra-op:
- excessive bleeding.
- nerve damage e.g. facial nerve causing facial droop.
- jaw fracture.
- salivary duct damage causing mucocele.
Post-op:
- breakdown/dehiscence.
- swelling.
- acute or chronic anorexia.
- recurrence / mets.
- oronasal fistula.

Question 22

1. Types of oral cavity trauma.
2. Oral cavity trauma first principle Tx.

Answer 22

1. Bites, burns, FB, “high rise” falls, impaling, malicious injuries, RTA.
2. Hx, triage, post-stabilisation, primary/secondary repair.

Question 23

Glossectomy indications, technique, complications.

Answer 23

Masses, injury, infection etc.
Stay-sutures on part of tongue about to be removed to retract tongue from oral cavity, and stay-sutures on part of tongue that is staying as tongue is elastic and will spring back towards the larynx once free from rest of tongue.
May be full or may be partial.
Incise, remove, suture.
Ensure airway packed as fast bleeding.
- local pressure, electrosurgery, ice cold saline, suture quickly.
– sutures to close off incision, full-thickness sutures through tongue.
– monofilament absorbable suture material.
+/- feeding tube.
Complications = haemorrhage, failure to cure, failure to heal, tongue function (eating, grooming, panting).

Question 24

Tonsillectomy indications.
Tonsillectomy technique.
Tonsillectomy complications.

Answer 24

Tumour, BOAS.
Allis issue forceps, open up tonsillar fossa (may already be out of tonsillar fossa), pull tonsil out w/ as much tension as possible, snip tonsil out at the base. Expect some bleeding, sew over the tonsillar crypt as quickly as you can to reduce bleeding.
Intra-op and post-op complications involve bleeding, recurrence (if tumour).