Parotid Gland Surgery
What is the parotid gland?
Parotid glands are paired major salivary glands overlying the jaw in front of the ear. They secrete saliva and digestive juices to help with chewing, swallowing and digestion. The facial nerve is the nerve that controls all the muscles of facial expression. Its branches run through the deep and superficial lobes of the parotid gland. There are also multiple lymph nodes lying in the parotid gland.
I have a lump in my parotid gland, is it worrying?
The majority of parotid tumours or neoplasms are non-cancerous (benign). The most common type of primary tumour in the parotid is a pleomorphic adenoma. In Australia, the most common cancerous parotid tumours are intra-parotid lymph node deposits from skin cancers. Dr Shaw will conduct a focused history and thorough head and neck examination for clues to the pathology. Fine needle aspiration biopsy under ultrasound guidance has a reasonable ability to differentiate benign from malignant tumours. However, the only definitive way to confirm the diagnosis is by performing a parotidectomy and sending the lesion to for formal histopathology.
Symptoms of parotid tumours:
A visible lump in front of the ear
A hard nodule in the gland
Facial asymmetry
Weakness of eye closure or muscles of facial expression such as those for smiling or frowning
Previous head and neck skin cancers on the same side
What is a parotidectomy?
There are multiple types of parotidectomy depending on the indications for surgery and the location of the tumour in the gland.
Superficial parotidectomy is where all the gland superficial to the branches of the facial nerve is removed. This is often performed for when cancers like squamous cell carcinoma or melanoma have metastasised or spread to the lymph nodes located within the gland.
A partial parotidectomy is removing a parotid tumour with a cuff of normal gland around it without performing more comprehensive surgery. A partial parotidectomy is often performed for benign tumours like pleomorphic adenomas and Warthin’s tumours.
A total parotidectomy is removing both the superficial and deep lobes of the parotid gland. Occasionally this is due to advanced tumours, and sometimes requires sacrifice of branches of the facial nerve.
How does Dr Shaw perform a parotidectomy?
An incision is placed in front of the ear wrapping down the neck similar to a mini facelift incision. It is often barely visible. A skin flap is raised on the parotid fascia towards the face. The key step is identifying and preserving the facial nerve trunk as it enters the gland from the tympanomastoid suture. Dr Shaw routinely uses intra-operative neuromuscular monitoring to help identify the facial nerve and preserve its branches.
Occasionally, in the setting of malignant tumours or advanced disease, a neck dissection may also be required. This is where draining of lymph nodes from the neck are removed.
What are the risks of a parotidectomy?
Like any other operation there are risks bleeding and infection. Some specific risks related to parotidectomy include facial palsy, salivary gland leak, and Frey’s syndrome. The most significant complication is a permanent facial palsy. This occurs in about 4% of patients and is often in cases where extensive surgery is required for aggressive tumours.
It is not uncommon to have a temporary weakness in a muscle of facial expression (called a facial paresis). The branches of the facial nerve are very small and sensitive to both mechanical and chemical injury related to surgery and the healing process. This occurs in about 20-40% of parotidectomy patients, but usually recovers within a few weeks.
Salivary leaks occur when some fluid or saliva from the remaining parotid gland tissue finds a path to and discharges on the skin. This happens when eating via a pinhole sized opening.
Frey’s syndrome (also called gustatory sweating) is where the nerves supplying the parotid gland connect with the sweat glands. This causes sweating on the overlying skin of the cheek when eating or salivating. It can be treated with botox if persistent and problematic. `
Will I have a contour defect after parotidectomy?
Dr Shaw often uses a dermofat graft taken from the upper thigh to reconstruct the parotid defect. This may also reduce the risk of developing a salivary leak and Frey’s syndrome. The donor site will be closed with dissolving sutures and be quite inconspicuous.