Section 3


What is the name of the incision outlined above?

Modified Blair incision

For what operation is this most commonly used for?

Parotidectomy

Describe the main nerve at risk of the procedure and what are its main branches?

  • Facial nerve
  • Branches: temporal, zygomatic, buccal, marginal mandibular, cervical

Describe three methods of identifying this nerve intraoperatively.

  • Tragal pointer- triangular extension of cartilage inferiorly off the tragus and location of the facial nerve is approximately 1cm antero-inferiorly
  • Superior border of posterior belly of digastric, facial nerve runs superiorly and parallel
  • Root of styloid process: nerve lies laterally
  • Tympanomastoid suture 6-8mm deep to the nerve

What is Frey’s syndrome?

  • Gustatory sweating
  • Due to parasympathetic secretomotor fibres nerve being cut and healing onto the skin and controlling sweat glands due to common neurotransmitter (acetylcholine)

Name two other specific complications associated with this operation.

  • Ear numbness due to damage to greater auricular nerve
  • Seroma
  • Salivary fistula

Supporting Information

Parotid gland– surrounded by a layer of investing fascia (parotid sheath), mainly serous production but has some mucus acini. It has two poles (upper and lower) and 3 surfaces (lateral, anterior and deep).

Anatomical relations:

  • Anterior– masseter, mandibular ramus, medial pterygoid, stylomandibular ligament, superficial temporal and maxillary arteries, facial nerve
  • Deep– Sternocleidomastoid, posterior digastric, external carotid, mastoid process, styloid process with attached ligaments
  • Within gland– branches of facial nerve, retromandibular vein, external carotid (maxillary and superficial temporal artery), auriculotemporal nerve. 

Parotid duct– runs along the masseter and pierces the buccinator to drain the opposite second molar tooth.

Blood supply + lymphatic drainage + nerve supply

  • Arterial– external carotid branches (facial artery)
  • Vein– retromandibular vein
  • Lymphatic drainage– deep cervical nodes
  • Nerve supply-
    • Parasympathetic– secretomotor fibres; reach parotid gland via the otic ganglion “hitch-hiking along 3 nerves:
    • Sympathetic– vasoconstrictors from superior cervical ganglion, travel via external carotid artery plexus
    • Sensory– auriculotemporal nerve from CN V3 (mandibular trigeminal)

Parotidectomy– modified blair or facelift incision. 

Anatomy landmarks for the facial nerve

  • Tragal pointer- triangular extension of cartilage inferiorly off the tragus and location of the facial nerve is approximately 1cm antero-inferiorly
  • Superior border of posterior belly of digastric, facial nerve runs superiorly and parallel
  • Root of styloid process: nerve lies laterally
  • Tympanomastoid suture 6-8mm deep to the nerve

Complications; bleeding, sensation loss around ear (greater auricular nerve), salivary fistula, facial palsy, Frey’s syndrome, seroma

Frey’s syndrome– gustatory sweating due to parasympathetic secretomotor fibres nerve being cut and healing onto the skin and controlling sweat glands due to common neurotransmitter (acetylcholine). 

Investigate regions with iodine starch test. 

Treatment:

  1. Aluminium based deodorant
  2. Topical glycopyrrolate
  3. Botox
  4. Jacobson nerve neurectomy
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