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PAROTIDECTOMY PRESENTER: DR PRASHANTH L MODERATOR: DR R M LALITHA

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PAROTIDECTOMY

PRESENTER: DR PRASHANTH L

MODERATOR: DR R M LALITHA

CONTENTS

1. INTRODUCTION

2. SURGICAL ANATOMY

3. TYPES OF PAROTIDECTOMY

4. PREOPERATIVE EVALUATION

5. SUPERFICIAL PAROTIDECTOMY

6. TOTAL PAROTIDECTOMY

7. EXTENDED TOTAL PAROTIDECTOMY

8. COMPLICATIONS

9. REFERENCES

INTRODUCTION

A parotidectomy is the surgical excision (removal) of

the parotid gland, the major and largest of the salivary

glands.

The procedure is most typically performed due to benign

or malignant tumors.

The majority of parotid gland tumors are benign,

however 20% of parotid tumors are found to be

malignant.

Rule of 80’s:

-80% of parotid tumors are benign

-80% of parotid tumors are pleomorphic adenomas

-80% of salivary gland pleomorphic adenomas

occur in the parotid

-80% of parotid pleomorphic adenomas occur in the

superficial lobe

-80% of untreated pleomorphic adenomas remain

benign

SURGICAL ANATOMY

Parotid gland

The paired parotid glands

are the largest of the major

salivary glands

weigh, on average, 15–30

g.

Preauricular region

Boundaries

The parotid duct

Parotid gland is divided

by the facial nerve into

i. a superficial lobe

ii. a deep lobe

An accessory parotid gland

Superficial Muscular Aponeurotic

System (SMAS)

SMAS is a fibrous network that

invests the facial muscles, and

connects them with the dermis.

Platysma inferiorly;

Zygomatic arch superiorly

Facial nerve courses deep to the

SMAS and the platysma.

Parotid fascia

Facial nerve and

branches

Structures within the parotid gland

External carotid artery and its branches

Veins

Lymphatics:

Superficial nodes drains

auricle, anterior part of

scalp, upper part of face

Deeper nodes receives

lymph from external

acoustic meatus, middle

ear, auditory tube, nose,

palate and deep parts of

cheek.

Cervical lymphnodes

RELEVANT SURGICAL RELATIONS

Posterior: Cartilage of external auditory meatus;

tympanic bone, mastoid process,

sternocleidomastoid muscle

Deep: Styloid process, stylomandibular tunnel,

parapharyngeal space, posterior belly of digastric,

sternocleidomastoid muscle

Superior: Zygomatic arch, temporomandibular joint

TYPES OF PAROTIDECTOMY

Partial parotidectomy: Resection of parotid

pathology with a margin of normal parotid tissue.

This is the standard operation for benign pathology

and low grade malignancies

Superficial parotidectomy: Resection of the entire

superficial lobe of parotid and is generally used for

metastases to parotid lymph nodes e.g. from skin

cancers, and for high grade malignant parotid

tumors.

Total parotidectomy: This involves resection of the

entire parotid gland, usually with preservation of the

facial nerve

Extended Total Parotidectomy: Removal of the

superficial and deep parotid gland also may be

extended to involve adjacent structures.

PREOPERATIVE EVALUATION

A thorough history is obtained prior to consideration

for surgery.

Symptoms of sensory loss, trismus and facial

weakness are worrisome for local tumor invasion by

a malignant neoplasm.

The past medical history should include information

regarding any prior cutaneous lesions or

malignancies.

In addition, the patient should be queried about any

prior radiation exposure to the head and neck

including dental radiographs.

Smoking is associated with Warthin’s tumor and,

therefore, should be investigated.

This tumor can also occur bilaterally, thus any

history of a prior parotid tumor should be elicited.

Cranial nerve function should be examined and

facial nerve function should be evaluated carefully.

Facial nerve paralysis is usually an indication of

nerve invasion by a malignant tumor.

Fixation to the overlying skin, limited mobility of the

mass, and associated cervical lymphadenopathy

are other signs suggestive of malignancy.

FINE-NEEDLE ASPIRATION BIOPSY (FNAB)

It is an accurate and useful investigation for the

diagnosis of a parotid mass.

FNAB allows for improved patient selection for

surgery since it can identify conditions such as

reactive lymph nodes or cysts that might mimic

parotid neoplasms clinically.

The information gained by FNAB is useful for

patient counseling, surgical timing and planning,

and guiding the direction of preoperative

consultation

RADIOLOGY

Radiological investigation is not routinely required

with parotid tumors.

It is recommended for surgical planning with tumors

that are large, fixed, and are associated with facial

nerve involvement, trismus, and parapharyngeal

space involvement.

MRI is a valuable investigation with recurrence of

pleomorphic adenoma as it is often multifocal.

PREOPERATIVE CONSENT

Scar

Anesthesia in the greater auricular distribution

Facial nerve weakness

Facial contour

Prominence of auricle

Frey’s syndrome (gustatory sweating)

PREOPERATIVE CONSENT

Scar

Anesthesia in the greater auricular distribution

Facial nerve weakness

Facial contour

Prominence of auricle

Frey’s syndrome (gustatory sweating)

SUPERFICIAL PAROTIDECTOMY

Superficial lobe parotidectomy describes removal of all

or a portion of the parotid gland superficial to the facial

nerve.

The most common indications are:

1. Benign or low grade tumor of the superficial lobe of the

parotid gland

2. metastases to parotid lymph nodes from adjacent sites

of skin cancer or melanoma, or from cancer of the

external auditory meatus.

3. Access to the deep lobe of the gland or other

structures deep to the facial nerve.

4. Chronic inflammation of parotid gland, resistant to

conservative treatment.

ANAESTHESIA

General anaesthesia

Short-acting muscle relaxation for intubation only,

so that facial nerve may be stimulated and/or

monitored

No perioperative antibiotics unless specifically

indicated

Hyperextend the head, and turn to opposite side

Infiltrate with vasoconstrictor along planned skin

incision,

Keep corner of eye and mouth exposed so as to be

able to see facial movement when facial nerve

mechanically or electrically stimulated.

TECHNIQUE

A modified Blair incision

An alternative incision is

a modified face-lift

incision.

The ipsilateral face is

prepared with an antiseptic

solution and the surgical

field is draped with a

transparent adhesive

sterile drape.

Nerve electrodes are

placed in the ipsilateral

facial muscles and tested

for electrical integrity.

The skin incision is

made through the

subcutaneous tissues

and platysma muscle.

Greater auricular

nerve.

An anterior flap is

elevated superficial to

the greater auricular

nerve and the parotid

fascia.

Anterior flap- the

peripheral branches of

the facial nerve.

A posterior, inferior flap-

expose the tail of the

parotid gland.

The tail of the parotid gland is dissected

off of the sternocleidomastoid muscle

by dissecting deep to the posterior

branch of the greater auricular nerve.

Next, the posterior belly of the digastric

muscle is exposed with further

elevation of the tail of the parotid gland

The posterior belly of the digastric

muscle serves as a landmark for the

facial nerve.

During elevation of the tail of the

parotid, the integrity of the posterior

facial vein also is preserved if possible.

The preauricular space is

opened by division of the

attachments of the parotid

gland to the cartilaginous

external auditory canal

with blunt and sharp

dissection.

This plane of dissection

exposes the tragal

cartilage pointer which

serves as another

landmark for the facial

nerve.

A wide plane of

dissection from the

zygoma to the digastric

muscle is created to

facilitate exposure of the

facial nerve.

The gland is carefully

retracted anteriorly.

This exposes the

operative field for

identification of the facial

nerve.

The facial nerve is

identified using

anatomic landmarks:

1. Posterior belly of the

digastric muscle

2. Mastoid tip

3. Tragal cartilage pointer

4. Tympanomastoid

suture.

If the proximal segment

of the facial nerve is

obscured, retrograde

dissection of one or

more of the peripheral

facial nerve branches

may be necessary to

identify the main trunk.

When necessary, the

facial nerve can be

identified in the

mastoid bone by

mastoidectomy and

followed peripherally.

Once the facial nerve is

identified, the parotid

gland superficial to the

facial nerve is divided

carefully, preserving the

integrity of the nerve.

The exact location of the

facial nerve should

always be determined

prior to division of the

gland tissue.

The facial nerve is

followed peripherally,

the desired portion of

the gland is dissected

from facial nerve

branches and the

specimen removed.

The facial nerve is preserved except in cases when

confirmed malignancy is found invading the nerve.

In instances of facial nerve invasion by carcinoma,

facial nerve resection is performed.

Proximal and distal margins of the resected nerve are

examined histologically by frozen section to ensure

clear surgical margins.

If the tumor involves the stylomastoid foramen,

mastoidectomy is performed to identify the proximal

facial nerve in the fallopian canal to achieve a clear

margin.

Immediate nerve reconstruction by a nerve

interposition graft is usually indicated if facial nerve

resection is performed.

After the superficial

portion of the gland is

removed.

The wound is carefully

inspected and bleeding

sites are controlled with

bipolar electrocautery

or ligatures

The integrity of the

facial nerve is

confirmed visually and

by electrical stimulation

of the main trunk of the

facial nerve and all the

peripheral branches.

A neck dissection is performed for clinically positive

nodes.

For the clinically negative neck, the first echelon

nodes are inspected.

Enlarged or suspicious nodes are examined and a

neck dissection is performed if metastatic disease

is confirmed by frozen section.

The wound is irrigated,

realigned, and closed in

layers over a closed-

suction drain.

The drain is usually

removed on the first

postoperative day and

the skin sutures are

removed within one

week.

Adjuvant radiation therapy is recommended for

select malignancies including

i. metastatic cutaneous squamous cell carcinoma

ii. high-grade and advanced parotid malignancies

TOTAL PAROTIDECTOMY

Total parotidectomy is the total removal of the

superficial and deep parotid gland.

The operation may involve sparing or sacrifice of

the facial nerve branches or trunk depending on

tumor extent to the nerve.

INDICATIONS:

1. Metastasis to a superficial parotid node from a

primary parotid tumor or an extraparotid

malignancy

2. Parotid malignancy that indicates metastasis by

involvement of cervical lymph nodes

3. High-grade parotid malignancy with a high risk of

metastasis.

4. Primary parotid malignancies originating in the

deep lobe and for primary malignancies that

extend outside the parotid gland.

5. Multifocal tumors, such as oncocytomas, to

ensure complete removal

EXTENDED TOTAL PAROTIDECTOMY

Removal of the superficial and deep parotid gland

also may be extended to involve adjacent

structures such as the overlying skin, the underlying

mandible, the temporal bone and external auditory

canal, or the deep musculature of the

parapharyngeal space.

These extensions are dictated by tumor growth and

behavior.

SURGICAL TECHNIQUE:

1. Preparation

2. Incisions and flap elevation

3. Deeper dissection

4. Facial nerve mobilisation

5. Removal of superficial gland

6. Deep parotidectomy

7. Total Parotidectomy with Facial Nerve Sacrifice

8. Resection of Adjacent Structures and

Reconstruction

PREPARATION

The operation is performed with the patient under

general endotracheal anesthesia.

Endotracheal tube is positioned and taped to the

oral commissure and cheek opposite to the lesion.

The patient is placed in a 45° reverse-

trendelenburg position or lounge-chair position with

the head higher than the heart.

The head is turned to the opposite side of the

lesion, and the neck is extended by placement of a

rolled sheet under the shoulders.

The patient is prepared by sterile scrub and draped

so that the ear, lateral corner of the ipsilateral eye,

ipsilateral oral commissure, and entire ipsilateral

neck are visible in the field.

If facial nerve monitoring is to be used, the nerve

monitor is placed in the orbicularis oris and

orbicularis oculi muscles to ensure upper and lower

division monitoring.

The surgeon stands on the side of the patient

ipsilateral to the gland to be dissected, the assistant

stands at the head and opposite the surgeon, and

the scrub technician stands on the side of the

surgeon.

INCISIONS AND FLAP ELEVATION

INCISIONS AND FLAP ELEVATION

INCISIONS AND FLAP ELEVATION

DEEPER DISSECTION

FACIAL NERVE MOBILIZATION

A small curved clamp is oriented perpendicular to

the anticipated direction of the facial trunk to

elevate tissues layer by layer.

Scissors are never used for dissection down to the

nerve, and no tissue is cut in this area until the

nerve is seen.

Blunt dissection proceeds posterior to anterior until

the surgeon identifies the nerve as a white cord 2–3

mm wide.

REMOVAL OF THE SUPERFICIAL GLAND

The gland is separated at its edge, the temporal or

marginal branches being followed to the periphery.

The thickest fascia is encountered

posterosuperiorly; this must be divided sharply or

the surgeon will make tunnels into the gland along

the nerve.

Posteriorly- branches of the superficial temporal

vein may be encountered.

Vessels directly adjacent to the nerve branches should

not be cauterized until the superficial lobe is completely

mobilized.

After following a nerve branch to its peripheral

emergence from the parotid gland, the surgeon returns

to a proximal position along that nerve and searches

for another branch to follow.

Dissection progresses from posterior to anterior and

either superiorly or inferiorly until the superficial gland

has been completely separated from the facial nerve

and the deep parotid gland.

At this point, the surgeon should have a clear

impression of the relationship of the tumor to the

facial nerve, superficial gland, deep gland, and

surrounding structures.

It may be necessary to dissect along the tumor

capsule to separate it from the deep gland and

facial nerve.

Careful retraction and meticulous dissection can

prevent rupture of the tumor capsule, which is often

pivotal in the prevention of recurrence.

The gland is now left attached to only the parotid

duct.

The surgeon inspects this area to ensure that no

buccal branches are adherent to the duct.

The duct is divided and ligated, and the specimen is

sent for examination by the pathologist.

The wound should now be irrigated and the field

inspected for bleeding vessels, which are ligated.

DEEP PAROTIDECTOMY

The gland is completely freed from attachment to any

adjacent structures and sent for frozen-section

pathologic examination.

Small vessels around the deep gland adjacent to the

mastoid and trunk can be cauterized using the bipolar

forceps.

The wound is irrigated, and meticulous hemostasis is

achieved.

If necessary, the incision can be extended for neck

dissection at this time.

At the conclusion of the operation, a suction drain is

placed in the wound through a separate stab

incision in the postauricular skin and sewn into

place.

The wound is closed with interrupted absorbable

sutures

Dressing or antibiotic ointment can be applied.

Patient is awakened and extubated.

TOTAL PAROTIDECTOMY

WITH FACIAL NERVE SACRIFICE

If facial nerve function is normal preoperatively,

even in patients with malignancy, then the nerve

can be preserved with careful dissection of the

tumor off the nerve sheath.

If the nerve is paretic or fully paralyzed

preoperatively, then it is involved with tumor and is

normally resected during tumor resection.

Nerve that is clearly invaded by high-grade

malignant tumor should be resected with the

specimen to negative proximal and distal margins.

This may necessitate sacrificing peripheral

branches, divisions, or even the main trunk of the

facial nerve.

Intraoperatively, a nerve that is infiltrated with tumor

will appear swollen and usually darker than the

normal glistening white appearance of normal facial

nerve.

After negative proximal and distal facial nerve

margins are obtained, the nerve is reconstructed

with primary neurorraphy or grafting.

Mastoidectomy and nerve mobilization may be

necessary to attain proper length of the facial nerve

for tension-free anastomosis.

Appropriate grafts include:

i. ipsilateral greater auricular nerve if it is not

involved with tumor

ii. ipsilateral sural nerve graft.

Peripheral branches can be grafted

i. proximal facial nerve

ii. ipsilateral hypoglossal nerve

RESECTION OF ADJACENT STRUCTURES

AND RECONSTRUCTION

The operation may be extended to involve resection

of adjacent structures that are involved with tumor.

It may include

i. lateral or subtotal temporal bone resection,

ii. partial mandibular resection,

iii. resection of the overlying skin,

iv. resection of portions or all of the auditory canal,

and

v. resection of surrounding musculature.

Options for reconstruction include

i. primary closure,

ii. dermal fat grafting,

iii. muscle transposition with loco regional flaps of

the sternocleidomastoid or pectoralis muscles,

iv. micro vascular cutaneous, musculocutaneous,

and innervated muscular flaps.

Again, the reconstruction will be guided by the

functional and aesthetic goals of the surgeon and

patient.

COMPLICATIONS

1. Hematoma

2. Infection

3. Facial nerve palsy

4. Salivary fistula

5. Gustatory sweating/ Frey’s syndrome

6. Cosmetic deformity

Inadequate hemostasis before

closure.

Suction drain reduces

possibility of postoperative

hematoma.

Treatment:

i. Evacuation of hematoma

ii. Control of bleeding points

iii. Reinsertion of suction drain

and closure.

HEMATOMA

Infection is rare

Some tumors presents with obstructive symptoms if

infected.

Prophylactic antibiotics are given if operating on an

infected gland.

INFECTION

Temporary or permanent

Partial or total

Neuropraxia- due to

stretching of the nerve.

If the nerve is intact at the

end of procedure-

recovery within few weeks.

FACIAL NERVE PALSY

If the palsy is severe and recovery is prolonged-

transcutaneous nerve stimulation of facial muscles.

Problems with eye closure-

i. protective glasses or tape the eyelid to prevent

exposure keratitis.

ii. Temporary tarsorrhaphy or paralysis of eyelid

elevator with botulinum toxin to allow closure of

upper eyelid.

When palsy is due to partial or total loss of facial

nerve:

i. reconstruction

ii. rehabilitation of face

Presents after suture

removal at the suture

line and posterior to

ear lobule.

Pressure dressing.

Drains

Anticholinergic drugs-

to reduce salivary

secretion

SALIVARY FISTULA

Auriculotemporal

syndrome.

60% of all

parotidectomy cases.

Discomfort, localized

facial sweating and

flushing during

mastication.

FREY’S SYNDROME

Due to parasympathetic

and sympathetic

secretomotor stimuli

misdirected to

cholinergic receptors of

sweat glands during

healing after parotid

surgery.

The iodine test administered

by applying an alcohol–

iodine–oil solution (3 g

iodine, 20 mL castor oil, and

200 mL absolute alcohol)

described by Laage-Hellman

The solution was applied on

the lateral portion of the face

that had been surgically

treated and the upper region

of the neck.

The solution was allowed

to dry and was covered

lightly with starch

powder.

The patients received

lemon candy for a

gustatory stimuli for 10

minutes.

Discoloration of the

starch iodine mixture

was interpreted as a

There is no effective treatment, but various options

are described:

i. Injection of Botulinum Toxin

ii. Surgical transection of the nerve fibers

iii. Application of an ointment containing

an anticholinergic drug such as scopolamine

Incision mark

Sunken cheek due to

loss of parotid gland and

fat.

Rotation of

sternomastoid muscle

flap at the time of

surgery.

Free flaps.

COSMETIC DEFORMITY

REFERENCES

1. Salivary Gland Disorders: Eugene N. Myers, Robert

L. Ferris; Springer.

2. Parotidectomy : Johan Fagan : Open Access Atlas

Of Otolaryngology, Head & Neck Operative Surgery

3. Maxillofacial Surgery: Second Edition; Volume 1:

Peter Wardbooth.

4. Operative Maxillofacial Surgery; John D Langdon

and Mohan F Patel.

5. Internet

Thank You