Parotid Gland Surgery

Parotid gland surgery is one of the most important and technically demanding topics in ENT and Head-Neck surgery because it involves operating close to the facial nerve. Therefore, students must clearly understand the types of parotidectomy, indications, surgical steps, facial nerve landmarks, and postoperative complications such as Frey’s syndrome, facial palsy, and salivary fistula.

Applied Surgical Anatomy of Parotid Gland 

The parotid gland is the largest salivary gland. It lies in the parotid bed between the mandible and the mastoid region. Importantly, the facial nerve divides the gland into superficial and deep lobes, which becomes the foundation for planning surgery.

Key Anatomical Points

• The facial nerve exits the skull through the stylomastoid foramen and enters the parotid gland.
• It divides into the Temporofacial division & Cervicofacial division, and forms the pes anserinus.
• The facial nerve then gives 5 terminal branches: Temporal, Zygomatic, Buccal, Marginal mandibular & Cervical.

Parotid Duct (Stensen’s duct)

• Runs over the masseter, turns medially, and pierces the buccinator.
• Opens opposite the upper 2nd molar tooth.

Important Relations

• The posterior belly of the digastric muscle is a key landmark for the facial nerve trunk.
• The retromandibular vein lies deep.
• The external carotid artery lies deep and divides inside the gland.

Indications of Parotid Surgery

• Benign parotid tumours (Pleomorphic adenoma, Warthin tumour)
• Malignant tumours (Mucoepidermoid carcinoma, Adenoid cystic carcinoma)
• Deep lobe tumours
• Recurrent parotid tumours
• Parotid abscess (rarely surgical parotidectomy, mostly drainage)
• Vascular malformations
• Parotid fistula/sialocele (selected cases)

Classification of Parotid Gland Surgeries.

1. Extracapsular dissection (ECD)
2. Superficial parotidectomy
3. Total conservative parotidectomy.
4. Radical parotidectomy

1. Extracapsular dissection (ECD)

It is indicated for mobile lesions in the parotid tail and small, superficial tumours within the superficial lobe. It is not suitable for inflammatory lesions, large tumours, those extending into the deep lobe, or cases where malignancy is suspected. The procedure involves a similar incision and skin flap elevation as in standard parotidectomy. The tumour is removed by developing a plane between its capsule and normal parotid tissue, without identifying the facial nerve. A nerve stimulator is used during dissection. If the facial nerve position is unclear, partial parotidectomy with formal nerve identification is recommended.

2. Superficial Parotidectomy

The principle of surgery is to expose the facial nerve and then remove the superficial lobe of the parotid gland and the tumour around the facial nerve. Depending upon the extent of parotidectomy, it can be further divided into total superficial parotidectomy and partial superficial parotidectomy (the tumour and a cuff of normal tissue). Partial superficial parotidectomy is practised in the UK more commonly.

Steps of Superficial Parotidectomy:

1. Patient Positioning: Place the patient in the reverse Trendelenberg (head-up) position.

2. Incision: A Modified Blair incision in the preauricular crease extends inferiorly to the ear lobe, and then a circum-lobular incision is made around the ear lobule up to the mastoid tip. Then gently curving downwards from the mastoid tip along the sternocleidomastoid muscle and turning anteriorly into a natural neck crease, approximately two fingerbreadths below the angle of the mandible (at the hyoid bone level).

3. Haemostasis: Infiltrate the area with adrenaline (1:100,000) to reduce bleeding.

4. Raise Skin Flaps: Elevate skin flaps superficial to the parotid fascia, including the SMAS (superficial musculoaponeurotic system) layer. This thick flap reduces the risk of Frey’s syndrome in the postoperative period.

5. Mobilise Parotid Gland: Dissect the parotid gland from the tragal cartilage, sternocleidomastoid, and posterior belly of digastric muscles. At this time, section the greater auricular nerve if necessary, preserving the posterior branch (provides sensory supply to ear lobule) when possible. Judicious use of traction will aid in the identification of the facial nerve. Avoid excessive traction to prevent capsule rupture and tumour spillage. If spillage occurs, it should be contained and excised to reduce the risk of tumour seeding.

6. Facial Nerve Trunk Identification: Identify the facial nerve using anatomical landmarks:

• Cartilaginous pointer (tragal pointer). The facial nerve lies 1 cm deep and slightly anterior and inferior to the pointer. A cartilaginous pointer is a sharp triangular piece of cartilage of the pinna and “points” to the nerve. The tragal pointer is slightly mobile when retracted, so care must be taken when using this as a landmark.
• Tympanomastoid suture. The nerve lies 6–8 mm deep to this suture. The facial nerve lies 6–8 mm deep to this suture. This groove is very easy to feel, and this is an extremely reliable landmark. The surgeon can get a ‘feel’ for where the nerve is expected to be.
• Styloid process. The nerve crosses laterally to the styloid process. Whilst easy to palpate, it lies deep to the exit of the nerve from the stylomastoid foramen, so dissection onto the styloid may increase the risk of facial nerve damage
• Anterior border of the posterior belly of the digastric muscle. If the posterior belly of the digastric muscle is traced backwards along its upper border to its attachment to the digastric groove, the nerve is found to lie between it and the styloid process. The facial nerve leaves the stylomastoid foramen immediately anterior to the attachment of the muscle to the digastric groove.
  
• Tumour Removal: Dissect the superficial lobe or relevant part of the parotid gland and tumour from the branches of the facial nerve.
• Haemostasis & Wound Closure: Achieve haemostasis and place a drain before closing the wound.

Surgery For Recurrent, Soft or Large tumours. Identification of the facial nerve main trunk is difficult in such cases; it is better to locate a major branch of the facial nerve and do a retrograde dissection.

• Zygomatic and Temporal Branches: These cross the zygomatic arch anterior to, and within 1–2 cm of, the superficial temporal artery.
• Marginal Mandibular Branch: It can be located at the angle of the mandible, superficial to the facial vessels.
• Cervical Branch: It is located where it pierces the deep fascia below the body of the mandible.

3. Total conservative parotidectomy.

It is indicated for deep lobe tumours, malignant tumours, vascular malformations, or large tumours where involvement of the tumour between superficial and deep lobes is doubtful. It may also be necessary when tumour spillage occurs during superficial parotidectomy. Typically, the procedure begins with superficial parotidectomy, followed by mobilising the facial nerve and developing a plane deep to the main nerve trunk. The tumour and any remaining parotid tissue are removed, often through extracapsular dissection. All facial nerve branches are carefully identified and preserved during the procedure. Haemostasis is achieved, and a drain is placed before closing the wound.

4. Radical parotidectomy

It is indicated when preoperative facial paralysis is already present in the patient or when a malignant tumour circumferentially involves the nerve. The procedure involves the removal of the entire parotid gland, including the facial nerve. In such cases, simultaneous nerve grafting or other facial reanimation procedures are typically employed to address the resulting facial nerve deficit.

Complications of Parotid Surgery

Before undergoing superficial or total conservative parotidectomy, patients should be informed and written consent should be taken about the following potential complications:

1. Facial Weakness: Temporary or permanent facial weakness may occur. Neuropraxia typically recovers in 4-6 weeks, while more severe injuries may take 6-12 months or may not fully recover.

2. Sensory Loss: Sensory loss around the mandible and ear lobule (due to greater auricular nerve damage) is common but often improves after 12 months. Preservation of the nerve’s posterior branch can help reduce this effect.

3. Cosmetic Defects: Incisions rarely cause major cosmetic concerns, but loss of bulk behind the mandible may be visible, especially in thin patients. Fat transfer can help mitigate this.

4. Frey’s Syndrome (Gustatory sweating or flushing): There is abnormal innervation of the sweat glands present in the skin by parasympathetic secretomotor fibres that were originally supplying the parotid gland to produce saliva. After parotid surgery, these fibres mistakenly stimulate sweating instead of causing salivary secretion from the parotid during meals. It usually manifests several months after the parotid surgery. It is characterised by sweating and flushing of the preauricular skin area during mastication, causing social embarrassment to the person.
Treatment options.

• Tympanic neurectomy to intercept the parasympathetic fibres at the level of the middle ear.
• Placement of fascia lata between the skin and the underlying fat to prevent innervation of sweat glands.
• Anti-perspirant application can be used.
• Subcutaneous injections of botulinum toxin (repeated at 6–12 monthly intervals).
• The risk of Frey’s syndrome can be reduced by elevation of skin flaps superficial to the parotid fascia, including the SMAS (superficial musculoaponeurotic system) layer during the surgery. This thick flap prevents secretomotor fibres from reaching the sweat glands and reduces the risk of Frey’s syndrome in the postoperative period.
• Use of interpositional flaps (e.g. sternomastoid) .
• In many cases, simple reassurance is sufficient for treatment.

5. Sialocoele or Salivary Fistula: Except when we remove the complete gland in total conservative or radical parotidectomy, saliva leaks from the cut surface of the gland. It can also result from duct damage. The saliva can form a collection (sialocoele) or leak through the site of incision (fistula), typically within a few days post-surgery. Sialocoele can be quite tense and painful, especially during eating and may require repeated aspiration. Fistula need compressive dressing and strict wound hygiene. Antibiotics should be considered to prevent secondary infection. Both conditions usually resolve within 1–2 weeks. Hyoscine patches can reduce saliva production, and if conservative measures fail, ultrasound-guided botulinum toxin can be injected into the main/residual parotid gland, which stops saliva production and reverses within 2–3 months.

6. Stump Neuroma: Painful neuromas may form after greater auricular nerve injury. It presents as a tender nodule just anterior to the sternomastoid muscle. Local excision of the nodule and then burying the fresh nerve end in the muscle can prevent recurrence. Preservation of the posterior branch of the greater auricular nerve may also reduce the risk of stump neuroma.

7. First Bite Syndrome: Intense pain in the parotid gland may occur before eating and subsides quickly after beginning to eat. It occurs as a result of sympathetic denervation of the remaining parotid tissue. Treatment includes botulinum toxin injections into the parotid gland or medications like gabapentin or Pregabalin.

8. Trismus: Mild, transient inflammation of the masseter muscle is possible.

Table: Summary of Parotid Surgeries

Surgery	Facial nerve identification	Gland removed	Main indication
Extracapsular dissection (ECD)	No formal trunk identification	Only tumour + cuff	Small benign superficial tumours
Superficial parotidectomy	Yes (main trunk + branches)	Superficial lobe	Most benign superficial lobe tumours
Total conservative parotidectomy	Yes	Superficial + deep lobes	Deep lobe tumour / malignancy without nerve invasion
Radical parotidectomy	Facial nerve sacrificed	Entire gland + nerve	Malignancy involving facial nerve

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High-Yield Points for NEET PG and University Exams

• Facial nerve identification is the most critical step in parotid surgery, and the tympanomastoid suture is the most reliable landmark. The facial nerve lies 6-8 mm deep to the tympanomastoid suture and 1 cm deep to the tragal pointer.
• Extracapsular dissection does not require formal nerve identification, but a nerve stimulator is always used throughout the procedure.
• Superficial parotidectomy involves identifying the main trunk first and then dissecting distally, whereas retrograde dissection is used for recurrent or large tumours where the main trunk is difficult to locate.
• Total conservative parotidectomy preserves the facial nerve while removing the entire gland, hence the term “conservative.”
• Radical parotidectomy is indicated only when the facial nerve is already paralysed preoperatively or when the nerve is circumferentially involved by malignancy.
• Frey’s syndrome results from aberrant regeneration of parasympathetic fibres to sweat glands, and prevention is achieved by raising a thick SMAS flap.
• First bite syndrome is caused by sympathetic denervation of remaining parotid tissue and is treated with gabapentin or botulinum toxin.
• The greater auricular nerve posterior branch should be preserved whenever possible to maintain earlobe sensation and prevent stump neuroma.
• Tumour spillage during parotidectomy requires immediate containment, irrigation, and conversion to total conservative parotidectomy.
• The marginal mandibular branch is the most commonly injured branch during parotid surgery because of its superficial course over the mandible.

NEET PG-Style MCQ’s

1. 1: A 45-year-old woman presents with a 2 cm mobile, painless swelling in the tail of the right parotid gland. Ultrasound suggests pleomorphic adenoma. The most appropriate surgical procedure is: A. Superficial parotidectomy B. Extracapsular dissection C. Total conservative parotidectomy D. Radical parotidectomy.
2. 2: The most reliable surgical landmark for identifying the facial nerve trunk during superficial parotidectomy is: A. Tragal pointer B. Styloid process C. Tympanomastoid suture D. Posterior belly of digastric.
3. 3: A patient develops sweating over the preauricular region while eating, 8 months after superficial parotidectomy. The most likely diagnosis is: A. First bite syndrome B. Frey’s syndrome C. Sialocoele D. Stump neuroma.
4. 4: The most effective treatment for established Frey’s syndrome is: A. Tympanic neurectomy B. Topical antiperspirants C. Subcutaneous botulinum toxin D. SMAS flap.
5. 5: Which parotid procedure is indicated for a deep lobe pleomorphic adenoma without facial nerve involvement? A. Extracapsular dissection B. Superficial parotidectomy C. Total conservative parotidectomy D. Radical parotidectomy.
6. 6: A patient develops a painful, tense swelling under the parotid flap on postoperative day 4. The swelling increases during meals. The most appropriate initial management is: A. Reoperation B. Antibiotics alone C. Aspiration of the collection D. Botulinum toxin injection.
7. 7: During parotid surgery for a large recurrent pleomorphic adenoma, the main facial nerve trunk cannot be identified. The best alternative approach is: A. Convert to radical parotidectomy B. Identify a peripheral branch and perform retrograde dissection C. Abort the procedure D. Perform extracapsular dissection.
8. 8: A patient develops intense pain in the parotid region just before starting to eat, which subsides after the first few bites. This complication is called: A. Frey’s syndrome B. Stump neuroma C. First bite syndrome D. Sialocoele.
9. 9: The facial nerve lies approximately how deep to the tragal pointer? A. 2-3 mm B. 5-6 mm C. 1 cm D. 2 cm.
10. 10: Which branch of the facial nerve is most vulnerable during parotid surgery? A. Temporal branch B. Zygomatic branch C. Buccal branch D. Marginal mandibular branch.

MCQ Answers

1: B. 2: C. 3: B. 4: C. 5: C. 6: C. 7: B. 8: C. 9: C. 10: D.

Clinical Case Scenarios for Practical Exams and Viva

Case 1. A 52-year-old woman presents with a 3-year history of a slowly enlarging, painless swelling in the right preauricular region. The swelling is firm, mobile, and measures 3.5 cm in diameter. There is no facial weakness. Fine needle aspiration cytology suggests pleomorphic adenoma. Most likely diagnosis: Pleomorphic adenoma of the superficial lobe of the parotid. Best next step: Superficial parotidectomy with facial nerve preservation. What intraoperative landmark would you use to identify the facial nerve? The tympanomastoid suture is the most reliable landmark. What complication might she develop 6 months after surgery? Frey’s syndrome (gustatory sweating).

Case 2. A 65-year-old man presents with a fixed, hard mass in the left parotid region associated with complete left facial paralysis of 3 months duration. MRI shows a 4 cm infiltrative mass involving both parotid lobes and encasing the facial nerve. Most likely diagnosis: Malignant parotid tumour (likely adenoid cystic carcinoma or squamous cell carcinoma) with perineural invasion. Best next step: Radical parotidectomy with facial nerve sacrifice and simultaneous nerve grafting. What nerve graft is most commonly used? Greater auricular nerve or sural nerve. What static procedure may also be needed? Gold weight insertion in the upper eyelid for corneal protection.

Case 3. A 28-year-old woman undergoes superficial parotidectomy for a Warthin tumour. On postoperative day 3, she develops a soft, fluctuant swelling under the incision that increases in size when she eats. There is no fever or erythema. Most likely diagnosis: Postoperative sialocoele. Best next step: Aspiration of the collection and application of a compressive dressing. If this fails repeatedly, what is the next option? Ultrasound-guided botulinum toxin injection into the residual parotid gland. What medication can reduce salivary flow? Hyoscine patches.

Case 4. A 48-year-old man presents with a tender nodule just anterior to the sternocleidomastoid muscle, 18 months after superficial parotidectomy. The nodule is exquisitely tender to palpation, and he experiences shooting pain when he wears a shirt collar. Most likely diagnosis: Greater auricular nerve stump neuroma. Best next step: Surgical excision of the neuroma with burial of the fresh nerve end into the sternocleidomastoid muscle. How could this have been prevented? Preservation of the posterior branch of the greater auricular nerve during initial surgery.

Frequently Asked Questions in Viva

• What is the difference between superficial parotidectomy and total conservative parotidectomy? Superficial parotidectomy removes only the superficial lobe lateral to the facial nerve, whereas total conservative parotidectomy removes the entire gland while preserving the facial nerve, making it necessary for deep lobe tumours.
• When is extracapsular dissection preferred over superficial parotidectomy? Extracapsular dissection is preferred for small (less than 3 cm), mobile, superficial, benign tumours in the parotid tail where the risk of facial nerve injury is low and cosmetic outcome is important.
• How can Frey’s syndrome be prevented during parotid surgery? Frey’s syndrome is prevented by raising a thick skin flap that includes the SMAS (superficial musculoaponeurotic system) layer, which acts as a barrier preventing aberrant parasympathetic fibres from reaching sweat glands.
• What is the management of intraoperative tumour spillage during parotidectomy? If tumour spillage occurs, the surgeon should immediately contain the area, irrigate thoroughly, excise any contaminated deeper tissues, and convert to total conservative parotidectomy to reduce recurrence risk.
• Which facial nerve branch is most commonly injured and why? The marginal mandibular branch is most commonly injured because it courses superficially over the body of the mandible, making it vulnerable during flap elevation and inferior dissection.
• What is first bite syndrome and how is it treated? First bite syndrome is intense pain in the parotid region before the first bite of a meal that subsides with continued eating, caused by sympathetic denervation; it is treated with gabapentin, pregabalin, or botulinum toxin injections.
• How long does temporary facial nerve weakness typically take to recover? Temporary facial weakness due to neuropraxia typically recovers within 4-6 weeks, while more severe injuries may take 6-12 months and may not fully recover.

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Download the full PDF Link:
Parotid Gland Surgery Best Lecture Notes Dr Rahul Bagla ENT Textbook

Reference Textbooks.

• Scott-Brown, Textbook of Otorhinolaryngology-Head and Neck Surgery.
• Cummings, Otolaryngology-Head and Neck Surgery.
• Stell and Maran’s, Textbook of Head and Neck Surgery and Oncology.
• Ballenger’s, Otorhinolaryngology Head And Neck Surgery
• Susan Standring, Gray’s Anatomy.
• Frank H. Netter, Atlas of Human Anatomy.
• B.D. Chaurasiya, Human Anatomy.
• P L Dhingra, Textbook of Diseases of Ear, Nose and Throat.
• Hazarika P, Textbook of Ear Nose Throat And Head Neck Surgery Clinical Practical.
• Mohan Bansal, Textbook of Diseases of Ear, Nose and Throat Head and Neck Surgery.
• Hans Behrbohm, Textbook of Ear, Nose, and Throat Diseases With Head and Neck Surgery.
• Logan Turner, Textbook of Diseases of The Nose, Throat and Ear Head And Neck Surgery.
• Arnold, U. Ganzer, Textbook of  Otorhinolaryngology, Head and Neck Surgery.
• Ganong’s Review of Medical Physiology.

Author:

Dr. Rahul Bagla
MBBS (MAMC, Delhi) MS ENT (UCMS, Delhi)
Fellow Rhinoplasty & Facial Plastic Surgery.
Renowned Teaching Faculty
Mail: msrahulbagla@gmail.com
India

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