Parotidectomy

Superficial Parotidectomy

• Indication: diagnostic and therapeutic excision of benign or malignant tumors that involve the superficial lobe of the parotid only

• typically preserves facial nerve

• resects majority of parotid gland lateral to facial nerve (controversy on amount of parotid required for removal)

Facial Nerve Markers

1. Tragal pointer: the facial nerve may be located 1 cm medial, inferior, and deep from tragal cartilage

2. Tympanomastoid Suture Line: the facial nerve is 6—8 mm deep to the inferior end of the tympanomastoid suture line

3. Digastric Attachment to Digastric Ridge: identifies the plane of the facial nerve

4. Retrograde Dissection from Distal Branches: may be required in select cases

5. Styloid Foramen: may identify the main trunk

Total Parotidectomy

• Indications: high-grade malignancy or deep lobe or facial nerve involvement

• excision of facial nerve may be indicated for malignant tumors (encasement or invasion of facial nerve) and select cases of pleomorphic adenomas (recurrent)

• Radical Parotidectomy: includes possible mandibulectomy, petrosectomy, periglandular skin, or facial nerve, indicated for aggressive malignant disease

Parotidectomy Complications

• Facial Nerve Paresis/Paralysis: iatrogenic injury should be repaired immediately (see p. 360)

• Hypesthesia of Greater Auricular Nerve: usually resolves within 9 months

• Salivary Fistulas: uncommon, usually spontaneously resolve in 2—3 weeks; Rx: probe wound to release fluid (aspiration), pressure dressing, surgical closure for prolonged drainage (may consider tympanic neurectomy)

• also hematomas, infection, flap necrosis, trismus, seromas, and recurrence

Frey's Syndrome (Gustatory Sweating)

• Pathophysiology: injury to the auriculotemporal nerve (sympathetic fibers) results in aberrant innervation of cutaneous sweat glands (which share the same neurotransmitter) by postganglionic parasympathetic fibers

• may occur up to 5 years postoperatively

• less incidence with the use of "thick" skin flaps

• SSx: sweating and reddening of skin during meals

1. Medical Management: antiperspirant and anticholenergic preparations (scopolamine, glycopyrrolate, diphemanil methylsulfate)

2. Surgical Management: tympanic neuronectomy (chorda tympani nerve section via tympanotomy approach), interpose a sheet of fascia lata or dermis between skin and parotid gland

3. Radiation Therapy: reserved for failed management with severe symptoms

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