Parotid Salivary Gland Surgery
The parotid gland is the largest of the salivary glands. There are two parotid glands, one on each side of the face, just below and to the front of the ear. The Stenson’s duct through which saliva is secreted runs from each gland to the inside of the cheek. The extra temporal facial nerve and its branches pass through the parotid gland and supply motor innervations to the muscles of facial expression, as well as to the post auricular muscles, the posterior belly of the digastric muscle, and the stylohyoid muscles.
Parotidectomy is a major surgical procedure to remove the parotid gland .The most common reason to remove this gland is due to an abnormal mass contained within. The mass itself can be found anywhere within the parotid gland. It rarely causes any pain or discomfort. In fact, the only symptom a patient would complain of is that they feel a lump there.
Most masses that develop in the parotid gland are due to benign tumors such as a pleomorphic adenoma and warthin’s tumor. These are generally painless and move around easily when manipulated. Even if benign, these tumors should be removed cosmetic reasons.
Rarely cancerous growths like mucoepidermoid carcinoma and acinic cell carcinoma can occur. If there is pain, numbness over the face, or facial paralysis, the likelihood of being cancerous growth is there.
Pre Op Evaluation
After taking proper history, then complete physical examination is performed. Intra oral examination and bimanual palpation also done.
The diagnostic tests are done to help the surgeon better plan for the surgery.
Some tests that may be performed include computed tomography (CT) scan, magnetic resonance imaging (MRI), and fine-needle aspiration biopsy (using a thin needle to withdraw fluid and cells from the growth). The Facial nerve integrity is carefully assessed before surgery.
/>The surgery is done under general anesthesia. An incision is made directly to the front or back of the ear and down the jaw line. The skin is folded back to expose the parotid gland. The various facial nerves are identified and protected during the surgery so as to avoid permanent facial paralysis or numbness. A superficial or total parotidectomy is then performed, depending on the type and location of the tumor. If the tumor has spread to involve the facial nerve, the operation is expanded to include parts of the bone behind the ear (mastoid) to remove as much tumor as possible. Before the incision is closed, a drain is inserted into the area to collect any leaking saliva, if a superficial parotidectomy was performed. The procedure typically takes from two to three hours to complete, depending on the extent of surgery and the skill of the surgeon.
Using Operating Microscope and Facial Nerve Stimulation
This surgery requires both highly technical micro-dissection as well as facial nerve monitoring and as such, is not just simply cutting the skin and removing the mass without regard to surrounding structures. It will be much easier to identify the branches of facial nerves this way. Facial nerve identification is done by microscopic dissection with nerve monitoring. It is this facial nerve identification that takes so much time.
Closing the Wound
After placing a redivac drain, the wound is closed in layers. The surgical drain is placed in order to remove any blood accumulation that may occur.
Complications of Surgery
If facial nerve is damaged, the person will potentially be unable to close the eye, smile, close the lips, kiss, etc. In essence, it is like having a severe Bell’s palsy.
Temporary facial paralysis may occur and is not unusual which will recover in few days time.
Other complications include infection and bleeding/hematoma that exist with any type of surgery. To minimize infection, an antibiotic is always given for a few days after surgery. To minimize bleeding/hematoma formation, a surgical drain is placed for a few days prior to removal.
Frey’s Syndrome: After complete healing, another complication may develop called “Frey’s Syndrome.” This is a complication in which the facial skin over the parotid gland sweats whenever you eat. This complication can be reduced if the surgeon makes every attempt to make the skin flap over the parotid gland as thick as possible.
Rarely, 1-2 weeks after surgery, a salivary fistula may develop between the residual gland and the skin resulting in saliva coming out the skin, usually somewhere along the incision or at the drain site. This complication usually occurs due to infection and very thin skin flap.
Although not considered a complication, the patient should be forewarned that the ear very often is numb as the great auricular sensory nerves to the ear do get cut during surgery. Fortunately, the ear numbness does very slowly resolve over 9-12 months, though it may never go quite back to normal.
Post op Care
Depending on how the surgery goes and how healthy the patient is to begin with, the patient may be able to go home the same day or the next day. The surgical drain is removed usually within 3 days and the sutures 5-7 days after surgery. Pain is not that bad in the vast majority of patients after this surgery with most people requiring narcotics only during the first week.
The patient is able to eat whatever they want but is forbidden from any exercise or heavy lifting the first 1-2 weeks after surgery.
After everything heals up, the incision should be barely noticeable.
However, the left facial region will appear somewhat sunken in compared with the normal opposite side, especially behind the jawbone, below the ear. Furthermore, the bigger the parotid mass is to begin with, the more asymmetric the appearance will be after the surgery. To prevent this the digastric muscle flap can be mobilized during surgery and sutured over to cover the defect.