Parotidectomy

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Continuing Education Activity

Parotidectomy is a common procedure in head and neck surgery. An appropriate incision and identification of multiple anatomical landmarks are necessary to accurately localize the facial nerve to avoid facial paralysis, a potentially devastating condition with a tremendous impact on the patient's quality of life. By far, the most common indication for parotid surgery is benign and malignant tumors of major salivary glands. This activity reviews the evaluation and treatment of parotid disease and highlights the role of the interprofessional team in evaluating and treating this condition.

Objectives:

  • Outline the presentation of a patient with a parotid tumor.
  • Describe the utility of preoperative imaging and cytology for parotidectomy.
  • Outline key surgical steps of parotidectomy.
  • Explain the importance of collaboration and communication among the interprofessional team to ensure the appropriate preoperative evaluation of the patient's disease-specific and general condition in an attempt to optimize postoperative outcomes of parotidectomy.

Introduction

Parotidectomy is the partial or complete removal of the parotid gland. Surgical candidates present for a variety of reasons that can include inflammatory conditions, certain infectious processes, congenital malformations, benign, or malignant neoplasms. Regardless of the indication for surgery, parotidectomy is a challenging procedure requiring experienced surgeons, due to the relationship of the gland to the facial nerve. Therefore identification and preservation of the facial nerve are the most crucial steps during the procedure (second only to oncologic safety in the case of known malignancy). Emphasis is on identification because, in the vast majority of cases, preoperative prediction of the relationship of the tumor to the nerve is not possible with much accuracy unless facial paralysis is already present prior to intervention.[1][2][3][4]

Anatomy and Physiology

The parotid gland is the largest major salivary gland. It is bounded by the masseter muscle anteriorly, zygomatic arch superiorly, anteromedial aspect of the sternocleidomastoid muscle inferiorly, and mandibular canal posteriorly. The gland is divided virtually into superficial and deep lobes by the facial nerve. The superficial lobe is lateral; the facial nerve and the deep lobe extend medially into the parapharyngeal space. However, this division is not anatomical since no dissectible plan exists between the pars superficialis and pars profunda. The parotid gland is encased by a prolongation of the deep cervical fascia, which divides into a deep and superficial layer to surround the gland. The superficial fascia extends from the masseter and SCM to the zygomatic arch. The superficial musculoaponeurotic system (SMAS) extends from the platysma to the superficial temporal fascia superiorly. It lies superficial to the parotid fascia and should not be confused with it.[1][4][5]

The duct of the parotid (Stenson's duct) exits the gland anteriorly and follows a course approximately 1 cm inferior to, and parallels, the zygomatic arch. After crossing the masseter, it pierces the buccinator muscle and enters the oral cavity facing the second maxillary molar. Salivary secretions of the parotid gland are more serous in contrast with the submandibular gland, which secretes a more mixed serous/mucous saliva. This is thought to explain the higher incidence of sialolithiasis within the submandibular gland.[6][5][7]

Relevant facial nerve anatomy is limited to its extemporal portion. After leaving the stylomastoid foramen, the main trunk of the facial nerve divides at the pes anserinus (figure 1) into two divisions: the temporofacial branching into frontal, zygomatic, and buccal branches, and the cervicofacial giving rise to the marginal mandibular and cervical branches. The course of the temporal branch can be predicted using surface landmarks as described by Pitanguy et al.: a line starting from a point 0.5 cm below the tragus in the direction of the eyebrow, passing 1.5 cm above the lateral extremity of the eyebrow (figure 2). The middle branch of the facial nerve (zygomatic/buccal) can be identified at Zuker's point, which lies midway on a line drawn from the root of the helix and the lateral commissure of the mouth with a 6 mm accuracy (figure 3). Note the buccal branch accompanies Stenson's duct over the masseter muscle. The marginal mandibular branch is located immediately in a plane deep to the platysma in close proximity to the inferior border of the mandible (figure 4). Along its course, it runs superficial to the facial vessels. The retromandibular vein travels through the parotid gland just deep to the facial nerve (figure 4). Since the facial nerve cannot be detected on a CT scan or MRI, the retromandibular vein serves as a useful radiologic landmark for the superficial and deep lobs of the gland. With the advent of 3 Tesla MRI, imaging of the intra-parotid facial nerve is sometimes possible; however, limitations remain, and there are concerns regarding accuracy and reproducibility, particularly in the setting of parotid neoplasms.[5][8][9][4][10][11]

Another structure worthy of mentioning is the greater auricular nerve (GAN), which travels parallel to the external jugular vein and splits into an anterior and posterior branch at the level of the gland. Injury to this nerve leads to loss of sensation in the skin at the angle of the mandible, the side of the upper neck, and the inferior half of the external ear. Of note, preservation of the anterior branch is often impossible as it frequently overlies the tail of the parotid and physically hampers exposure of the tail of the gland while raising the skin flap. The GAN can also be used as a nerve graft in the event of a facial nerve injury.[12]

The parotid gland contains lymph nodes in the superficial and deep lobes with a 90% to 10% distribution, respectively. The superficial group drains the pinna, scalp, eyelids, and lacrimal glands. The deep group drains the gland, middle ear, nasopharynx, and soft palate. The external auditory canal drains into both groups. This is important in the setting of sentinel lymph node biopsy, which may necessitate superficial or total parotidectomy for melanoma or other epithelial tumors of these regions.[5]

Indications

By far, the most common indication for parotidectomy is the removal of a neoplasm. In 75% to 80% of cases, these neoplasms are benign. Pleomorphic adenoma and Warthin tumors represent the majority of tumors. Of malignant tumors, mucoepidermoid and adenoid cystic carcinoma are the two most common, in that order. Chronic parotitis and recurrent sialadenitis can be served with a parotidectomy when medical treatment and sialoendoscopy fail or are unavailable. Other indications include caseating granulomas, toxoplasmosis, branchial cleft cyst, symptomatic lymphoepithelial cyst, or tuberculosis.[13][14][15][16][17]

Every patient should be evaluated properly before surgery. History and physical exam are essential for optimal decision making. Most patients are asymptomatic and present for an enlarging mass that was incidentally noted. Pain, if present, is not predictive of malignant histology.[1] A fixed mass could be malignant, inflammatory, or located in the deep lobe, though even benign masses can have limited mobility owing to the dense structure of the gland parenchyma, and so has more limited predictive utility. Examination of the oral cavity is useful to rule out the involvement of the parapharyngeal space. Facial nerve function is examined and documented with photographs, preferably. Worrisome signs include facial paralysis, trismus, and sensory loss.[1] The neck is palpated systematically; a parotid tail lesion might be confused with a jugulodigastric node. The British guidelines recommend US-guided fine-needle aspiration cytology (FNAC) for every patient.[18] It has an accuracy of 96% in distinguishing benign from malignant neoplasm.[19] It is important to correlate FNAC findings with clinical ones, for example, Warthin tumor on FNAC in a very young patient should necessarily reassure the surgeon into advising observation; this could represent a low-grade mucoepidermoid carcinoma since typically benign tumors present at more advanced ages. Each patient's entire clinical picture must be used to make decisions, rather than any single test.[20] Core biopsy is helpful when FNAC is not sufficient for diagnosis. It has a 96% sensitivity and 100% specificity for the diagnosis of malignancy.[21] The role of the frozen section is not clear; however, it may be able to differentiate malignancy from benign pathology with 99% specificity reported in some studies. Similarly, the determination of surgical margins may be possible with a notable exception of the tissue directly abutting the facial nerve. This is obviously variable subject to local pathologists' expertise, and for this reason, some authors prefer to forgo frozen sections and await permanent histology, counseling patients a second operation may be required. CT scan with contrast and MRI are helpful for the delineation of the extent of the lesion. Some clinicians prefer MRI. Most importantly, deep lobe lesions offer subtle findings on physical exam, making MRI potentially more helpful for diagnosis and preoperative planning. Static MRI parameters can help differentiate a benign from a malignant lesion with a diagnostic accuracy of 96% for dynamic contrast-enhanced MRI (DCE-MRI), and 95% when accounting for well-defined margins. MRI can also differentiate a malignant lesion from Warthin tumor and pleomorphic adenoma by studying the T-peak time, and this is especially useful since pleomorphic adenoma shows a 25% malignant transformation in contrast to Warthin tumor that shows only a 0.3% risk of malignant transformation.[22] MRI sialography proved to be a very useful technique replacing conventional sialography in most centers, it can also help with the evaluation of Sjogren disease by showing sialectasis clearly.[23] The availability of these more specialized MRI protocols may limit their utility in some centers. Neck dissection is always performed in the event of cervical metastasis. Levels I to V need to be dissected. For a node-negative neck, recommendations are less robust, with most authors suggesting dissection of levels I to III for high-grade lesions, T3/T4 tumors, and advanced ages, since these are risk factors for locoregional recurrence. Adjuvant radiotherapy is indicated for T3/T4 tumors, close or positive margins, and perineural/perivascular invasion. Nearly all adenoid cystic carcinoma can benefit from adjuvant radiotherapy. Therapeutic radiation is acceptable when surgery is not feasible. Conventional chemotherapy has demonstrated consistently poor outcomes as a primary treatment modality in salivary gland tumors, though it has been employed in ongoing trials in a palliative setting.[19]

The TNM staging system is frequently used for major salivary gland tumors. Aro et al. analyzed the data of 4520 patients from the United States National Cancer Database in an attempt the create an adapted lymph node staging system for salivary gland tumors. Mortality increased rapidly for every LN below 4 and at a slower pattern above 4. The staging system can also be criticized for encompassing all types of salivary gland tumors, while obviously, each histologic subtype behaves differently.[24]

Types of parotid surgery include[25]:

Extracapsular dissection: the facial nerve is not identified; the tumor is resected with the help of a facial nerve monitor (discussion beyond the scope of this chapter), used for benign lesions that are not pleomorphic adenoma.

Partial/superficial parotidectomy: the tumor is resected with a cuff of parotid tissue, used for benign lesions and lymph node metastasis into the superficial lobe.

Total parotidectomy: the entire gland is removed, used for aggressive malignant tumors, deep lobe tumors, sentinel lymph node excision when located in the deep lobe, vascular malformations, or in large tumors where the distinction between superficial and deep lobes is unclear.

Radical parotidectomy: the entire gland and the facial nerve is removed, mostly used when preoperative facial paralysis is well established, or circumferential involvement of the nerve by malignant tumor is encountered. Simultaneous nerve grafting or other facial reanimation procedures can be employed in this situation.

The patient needs to be counseled before surgery about the risk of temporary or permanent facial paralysis, the need for a suction drain, compressive dressing, and the possibility of an aesthetic contour deformity at the site of surgery.

Contraindications

There are no contraindications for parotidectomy as long as the patient is medically fit for general anesthesia. While there are reports of this procedure being performed under local anesthesia, this is very unusual and not routinely recommended. In certain cases, intubation might be challenging, for example, a tumor extending to the deep lobe/the parapharyngeal space or an extensive lesion invading the temporomandibular joint leading to trismus. In such situations, awake nasal fiberoptic intubation or a tracheostomy is necessary to secure the airway.

In certain conditions, parotidectomy might not be the optimal management. While most neoplasms are managed surgically, not all parotid masses are truly neoplastic. A patient with HIV and parotid swelling is more like to have intraparotid lymphoepithelial cysts and should have a detailed imaging and/or cytologic workup. Surgery is a last resort for this entity given the bilateral and progressive nature of the disease, and the higher risk of facial nerve injury. A more appropriate option in this scenario will be one of the following: observation, repeat aspiration, antiretroviral medication, sclerosing therapy, or radiation therapy.[26]

Equipment

Parotid surgery can be performed with the basic instruments set used in head and neck operations.

Bipolar is used for hemostasis.

Nerve monitoring can be done by asking a dedicated assistant to watch the face for twitches. Many surgeons use, in addition:

Intraoperative electrophysiological facial nerve monitor

and/or

Handheld nerve locator

Evidence in the literature suggests the following concerning electromyographic facial nerve monitoring[19]:

  • It decreases the rate of immediate facial weakness in primary surgeries
  • Help localize the facial nerve
  • Mandatory in extracapsular resection where by definition the facial nerve is not identified
  • Offers prognostic value regarding postoperative facial nerve function

Technique

The procedure is performed under general anesthesia with the endotracheal tube fixed to the contralateral side. Anesthesia team should be advised to avoid muscle relaxants because facial nerve function needs to be monitored. The neck is slightly extended, and the head turned away from the operated side. Half of the face is scrubbed with an antiseptic solution with care taken not to damage the eye. Drapes are placed with care to expose the hemiface and neck. If a nerve integrity monitor (NIM) is to be used, four electrodes are placed in the area of the temporal, zygomatic, buccal, and marginal mandibular branches of the facial nerve. Most surgeons prefer the modified Blair incision starting in a preauricular skin crease, around the lobule posteriorly, and extending inferiorly into a cervical skin crease. Some amount of skin should be left around the lobule to avoid pixie-ear (or satyr) deformity. An alternative is the modified facelift incision, which starts of similar to a modified Blair incision, however, after turning around the lobule, it extends posteriorly and superiorly into the retroauricular crease to continue within the occipital hairline.[27][28]

After incising the dermis and platysma, an anterior skin flap is raised in a plan between the SMAS and the superficial capsule of the parotid. A flap as thick as possible is advised to minimize the risk of Frey's syndrome as well as skin necrosis. Some surgeons advocate dissection in a plan just deep the superficial parotid fascia to further decrease the risk of Frey syndrome. Another option is to raise a supra-SMAS flap, taking care not to injure the subdermal plexus, and then raise a second, SMAS, flap in the style of a facelift. This SMAS flap can then be re-attached to minimize cosmetic deformity as well as Frey syndrome. Care is taken anteriorly not to damage branches of the facial nerve that become superficial at this level.[1]

Classically, the greater auricular nerve is sacrificed during the procedure; however, it is often possible to preserve its posterior branch. This is done by careful dissection along the nerve after its identification while raising the cervical subplatysmal flap; at the level of the bifurcation, the anterior branch is divided. If the entire nerve is to be sacrificed, this should be done as distal as possible to preserve a lengthy segment in case it is needed as a cable graft for facial nerve reconstruction (figure 4). The assistant plays a crucial role during the procedure by monitoring the face for muscle contractions even if a NIM is used, remembering the NIM and bipolar are good servants but bad masters (the surgeon should rely on direct observation before solely relying on electronic devices). Skin flaps are retracted and fixed with silk sutures or other retractive methods. Next, the tail of the parotid is dissected from the anterior border of the SCM muscle. The external jugular vein might be divided and ligated, though it can also frequently be preserved, as this might decrease bleeding during the procedure or provide a vessel for anastomosis for reconstructive flaps.[1]

The tail of the parotid is retracted superiorly, and the digastric muscle is identified. It serves as a landmark for the facial nerve, Saha, et al., measured the distance between the insertion of the posterior belly of the digastric over the mastoid and the facial nerve trunk and found it to be around 8 mm. The posterior belly of the digastric inserts into the mastoid tip, so tissue superficial to this structure can be divided with relative impunity once the distal marginal mandibular branch has been located. Dissection cephalad to the digastric muscle might injure the facial nerve as it exits the stylomastoid foramen between the mastoid and styloid processes. The attachments of the gland to the cartilage of the external auditory canal and the SCM muscle are divided to allow rotation and mobilization of the gland, a crucial step for identification of the facial nerve. A useful trick in adults is to palpate the mastoid tip and remove the non-salivary gland tissue overlying it and attached to the parotid. This can be done safely without concerns of facial nerve injury. Doing this in children is ill-advised since the mastoid tip is not well developed, placing the facial nerve at risk. The cartilage of the external auditory canal is dissected up to the level of the tragal pointer, another landmark for identification of the main trunk of the facial nerve, which is located roughly 1 cm inferior and anterior to it. Please note that the pointer is a cartilaginous structure that can be fractured or dislocated during the dissection; this factor needs to be taken into consideration when used as a landmark for the facial nerve. At this point, the surgeon can palpate the tympanomastoid suture. Emphasis is on palpation since it is often difficult to visualize the suture properly. It is considered the most consistent and reliable landmark for the main trunk of the facial nerve, which emerges a few millimeters deep to its lateral edge. Bushey et al. reported a mean distance between the facial nerve and the tympanomastoid suture of 4.9 mm.[29][30]

At this point the surgeon should have dissected the attachments of the gland from the external auditory canal, the SCM muscle, identified the digastric muscle, the tragal pointer, the tympanomastoid suture and is ready to begin the delicate and tedious task of identification of the facial nerve and the dissection along its branches (Figure 5). With a fine hemostat, the main trunk of the facial nerve is located and followed distally. It is important to dissect directly atop the nerve to visualize it the entire time directly. Divide the parotid tissue overlying the area of the facial nerve that has been dissected, never beyond that area. This can be done with fine scissors or an #12 blade while the glandular tissue is splayed with the hemostat. Hemostasis is ensured with bipolar diathermy and fine ties (when tightening the knots, care must be taken not to apply pressure on the facial nerve and its branches with the tightening finger). Once the pes anserinus is reached, it is advisable to visualize the entire portion of the facial nerve proximal to it to ensure that no early-branching occurred. Continue dissection along the branches of the facial nerve. Unless a complete superficial parotidectomy is planned, dissect only along branches proximal to the tumor. During the process, the retromandibular vein is often encountered deep to the facial nerve. When removing the superior part of the gland, the superficial temporal artery may need to be ligated; if so, this is performed just anterior to the auricle. When dissection continues anteriorly, the parotid duct is reached and divided if necessary. Remember that the buccal branch of the facial nerve is adjacent to the duct. Eventually, the tumor is removed with a cuff of parotid tissue or the entire superficial lobe.

When removing the deep lobe of the parotid, the surgeon can remove the superficial lobe completely or simply free it while keeping it attached anteriorly, reflecting it away and replacing it at the end of the procedure. Branches of the facial nerve are released from the tissue of the deep lobe with blunt and sharp dissection (figure 1). The tumor can be removed either through splayed branches of the facial nerve or by retracting it the mass inferiorly. If this proves to be difficult or inadequate, the transcervical approach with the division of the stylomandibular ligament provides excellent exposure of the parapharyngeal space, which includes the deep lobe of the parotid. Orabi et al. managed to removed 9 out of 9 benign tumors of the parapharyngeal space by dividing the stylomandibular ligament and retracting the mandible anteriorly. Vascular structures that need to be ligated and divided when necessary while maneuvering within the parapharyngeal space can include the external carotid, deep transverse facial and superficial temporal arteries, and the retromandibular and superficial temporal veins.[31]

Of note, when performing total parotidectomy for chronic parotitis, Stenson's duct needs to be followed up to the oral mucosa to avoid retention of any stones within a distal stump, which might lead to subsequent infection.

Benign tumors can almost always be dissected free from the facial nerve without problems. Even with pleomorphic adenoma where a certain margin is required to avoid recurrence, preservation of the facial nerve is always the rule and have a near-zero risk of recurrence when resected via true superficial parotidectomy. However, some malignant tumors might invade the nerve and raise the question of the sacrifice of the invaded branch. If preoperative facial paralysis exists, every attempt should be made to resect the tumor completely, even if it included resection of a segment of the facial nerve. When no preoperative paralysis is documented, it is acceptable to shave the tumor off the nerve (R1 resection), though many authors advocate resection of the affected branches and primary cable grafting. Isolated midfacial branches might not need to be repaired because the resulting deformity is often unnoticed.[14][32]

In the event of tumor spillage, when operating on a pleomorphic adenoma, the substance should be suctioned, and the site of capsule rupture closed. Some experts recommend against site irrigation since it might spread tumor cells all over the field. This spillage is believed to increase the risk of recurrence; however, there is no data to support this claim as of yet. The role of adjuvant radiotherapy in this setting is not clear.[19]

Before closure, the integrity of the facial nerve is checked, and function can be assessed with a nerve stimulator. Judicious nerve stimulation is advised since excessive electric stimulation might lead to neuropraxia. Sometimes mechanical trauma induces neuropraxia, and twitches are not observed. After meticulous hemostasis, a suction drain is inserted, and the wound closed in 2 layers.

In the recovery room, facial nerve function should be assessed as soon as possible. Some facial weakness is to be expected, particularly in total parotidectomy. This typically resolves with time so long as all branches were definitively identified and preserved, though full recovery can take many months.

The drain is left in place until the output is less than 15 to 50 cc in 24 hours. Duration of compressive dressing is variable, and some experts remove it when drain can be removed; others insist on the importance of a compressive dressing, especially after drain removal.

Coniglio et al. reported their experience with outpatient drainless parotidectomy. They established the viability of this approach in a properly selected patient[33]:

  • Extracapsular parotidectomy with identification of selected branches of the facial nerve when needed without identification of the main trunk
  • Minimal SMAS disruption and reconstruction at the end of the procedure primarily
  • When SMAS reconstruction is not possible, grafting material was used to fill the dead space
  • Jaw-bra for 48 hours and then overnight as tolerated

Complications

Hematoma: 0.9%. Meticulous hemostasis is the key to prevention, surgical reintervention to control bleeders.[34]

Facial paralysis: when anatomically identified and branches are known to be intact, the most probable cause of the paralysis is stretching. Incidence of transient paralysis is somewhere between 16.6% to 34%, and 90% will recover within 1 month; however, it could last as long as 18 months. Ability to close the eye without any corneal exposure needs be assessed and preventive measures should be taken to prevent exposure keratitis: ophthalmic drops and ointments, ophthalmologist consultation, gold weights, botulinum toxin are all potential treatment options in this interim.[35][36]

Seroma: managed by needle aspiration and compression dressing.[36]

Surgical site infection: prophylactic antibiotics are controversial. Extensive procedures with neck dissection +/- free flap reconstruction are at higher risk of infection and benefit from perioperative antibiotics. In more standard parotidectomy, intraoperative antibiotics are sufficient in most patients.

Frey’s syndrome: more accurately referred to as gustatory sweating. Patients report facial swelling and sweating at the site of the parotidectomy in occurrence with meals. Etiology is believed to be aberrant innervation of sweat gland with branches from the GAN after its division during surgery. This provides parasympathetic innervation to the normally sympathetic-innervated sweat glands. Diagnosis is made using the post-operative iodine-starch test (Minor test), where iodine starch placed on the affected area turns blue signaling sweat secretion. The incidence historically has been reported as high as 50 to 100%, though, with modern techniques and the use of SMAS flaps and thicker skin flaps at the time of initial elevation, this is greatly, greatly reduced. Should this develop, surgical treatment options can be disappointing, with the best results obtained using SMAS and superficial temporal artery flaps as a barrier between the surgical site and the skin. Gold standard treatment now is botulinum toxin injection. Relief of symptoms is obtained for 11 to 36 months. It works at the pre-synaptic level of the neuromuscular and neuroglandular junction by blocking the release of acetylcholine.[36][37]

First bite syndrome (FBS): painful spasm in the parotid region occurring at the first bite during mastication and decrease afterward. This pain accompanies each meal usually. It is a unique complication of surgeries targeting the deep lobe of the parotid gland, the parapharyngeal space, and the infratemporal fossa. Presumed etiology is the loss of sympathetic innervation of the parotid gland, which will lead to parasympathetic overshooting, resulting in contraction of parotid myoepithelial cells. This is supported by the fact that Linkov et al., only had one case of FBS when the entire parotid gland was removed. This case had ectopic parotid tissue left in place. Leaving the superficial lobe in place was found to carry a higher risk of FBS. Treatment is often challenging and begins with carbamazepine, which must be titrated. Most patients report improvement with time but never complete recovery. This is thankfully exceedingly rare, and really only encountered in extensive parotidectomy and extended neck dissections that violate the deep fascia of the floor of the neck, traumatizing the superior cervical ganglion.[38]

Loss of sensation around the ear, especially the lobule, occurs frequently. Significant but incomplete improvement is expected within one year. Preservation of the posterior branch of the great auricular nerve will hasten recovery.[36]

Amputation neuroma might occur when the GAN is transected; treatment is by simple excision.[36]

Surgical site depression occurs proportionally to the amount of tissue resected. Reconstruction with an SCM flap is helpful, but it has the drawback of creating a defect in the neck. An autologous fat graft can also be used.[36]

Trismus: inflammation of the master muscle, transient, and mild.[36]

Sialocele, or salivary fistula, is the result of the communication of a salivary duct or the gland with the skin. Saliva will be excreted through the wound. The incidence of this complication is between 4% and 14%. Treatment is by applying frequent drainage and compressive dressing. Sometimes decreasing oral intake is necessary; even completion parotidectomy has been suggested. Botulinum toxin injection offers a good therapeutic outcome by blocking salivary flow.[36]

Clinical Significance

Medical treatment plays a minor role when it comes to the treatment of most parotid diseases, therefore surgical intervention remains the cornerstone of treatment. Parotidectomy is an intricate procedure with functional, aesthetic, and potentially oncologic considerations. Knowledge of pertinent anatomy, preoperative optimization, techniques for identification of the facial nerve, and complications will allow the surgeon to safely and effectively care for patients requiring parotidectomy.

Enhancing Healthcare Team Outcomes

Parotid surgery is an emotionally intense experience for the patient and the family, with most fearing postoperative disfigurement. Fortunately, the results are frequently excellent for experienced surgeons. It is the physician’s duty to explain clearly to the patient what to expect, tailoring such discussions to the scenario of each individual patient. A small benign lesion may less likely result in permanent facial paralysis but is most dependent upon its location within the gland itself. An extensive malignant tumor poses a significant risk for facial nerve injury. An interdisciplinary approach is crucial to success. A free flap surgeon is consulted when significant resection is expected to discuss the pros and cons of vascularized tissue reconstruction versus local flap reconstruction. Nurses familiar with head and neck surgery are the keystone to an optimal postoperative outcome. They can recognize a hematoma that needs urgent drainage, a seroma, or a salivary fistula. The role of the radiologist and the pathologist cannot be overemphasized. Preoperative delineation of the tumor by an experienced radiologist can minimize surprises during surgery and help tremendously when counseling the patient since the surgeon had a clear idea of what type of parotidectomy he will be performing. A pathologist familiar with salivary glands is essential for accurate interpretation of FNAC, which allows appropriate patient counseling and might advise and wait a see approach in some cases like a Warthin tumor. When the diagnosis of malignancy is confirmed or in the event of spillage of pleomorphic adenoma during surgery, a radiation oncologist is consulted to discuss the need for adjuvant radiotherapy.[39][19][11][18]



(Click Image to Enlarge)
Total parotodectomy, main trunk of the facial nerve and its branches dissected free from the deep lobe before the excision of the latter. Asterisk on the Pes Anserinus.
Total parotodectomy, main trunk of the facial nerve and its branches dissected free from the deep lobe before the excision of the latter. Asterisk on the Pes Anserinus.
Contributed by Roger Moukarbel, MD

(Click Image to Enlarge)
The course of the temporal branch can be predicted using surface landmarks as described elegantly by Pitanguy et al: A line starting from a point 0.5 cm below the tragus in the direction of the eyebrow, passing 1.5 cm above the lateral extremity of the eyebrow
The course of the temporal branch can be predicted using surface landmarks as described elegantly by Pitanguy et al: A line starting from a point 0.5 cm below the tragus in the direction of the eyebrow, passing 1.5 cm above the lateral extremity of the eyebrow
Created and Contributed by Youssef El Sayed Ahmad, MD

(Click Image to Enlarge)
The middle branch of the facial nerve (zygomatic/buccal) can be identified at Zuker’s point that lies midway on a line drawn from the root of the helix and the lateral commissure of the mouth with a 6mm accuracy
The middle branch of the facial nerve (zygomatic/buccal) can be identified at Zuker’s point that lies midway on a line drawn from the root of the helix and the lateral commissure of the mouth with a 6mm accuracy
Contributed by Nabil Moukarzel, MD

(Click Image to Enlarge)
Superficial parotidectomy for a benign salivary gland tumor. 1: digastric muscle 2: main trunk of the facial nerve 3: cervical branch of the facial nerve 4: marginal mandibular branch of the facial nerve 5: great auricular nerve divided distally
Superficial parotidectomy for a benign salivary gland tumor. 1: digastric muscle 2: main trunk of the facial nerve 3: cervical branch of the facial nerve 4: marginal mandibular branch of the facial nerve 5: great auricular nerve divided distally
Contributed by Roger Moukarbel, MD

(Click Image to Enlarge)
Surgical landmarks for identification of the main trunk of the facial nerve
Surgical landmarks for identification of the main trunk of the facial nerve
Contributed by Johan Fagan, MD
Article Details

Article Author

Youssef El Sayed Ahmad

Article Editor:

Ryan Winters

Updated:

7/31/2021 3:26:46 PM

PubMed Link:

Parotidectomy

References

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