SlideShare a Scribd company logo
1 of 98
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
 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
 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
 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
 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
 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

More Related Content

What's hot

What's hot (20)

Carcinoma tongue
Carcinoma tongueCarcinoma tongue
Carcinoma tongue
 
Branchial Remnants and Branchial Cyst
Branchial Remnants and Branchial CystBranchial Remnants and Branchial Cyst
Branchial Remnants and Branchial Cyst
 
Thyroid surgical anatomy
Thyroid surgical anatomyThyroid surgical anatomy
Thyroid surgical anatomy
 
MAXILLECTOMY
MAXILLECTOMYMAXILLECTOMY
MAXILLECTOMY
 
Parotid gland swelling
Parotid gland swellingParotid gland swelling
Parotid gland swelling
 
Neck dissection
Neck dissectionNeck dissection
Neck dissection
 
Ranula
RanulaRanula
Ranula
 
Lymph node metastasis in neck (secondaries in cervical lymph nodes diagnosis...
Lymph node metastasis in neck (secondaries in cervical lymph nodes  diagnosis...Lymph node metastasis in neck (secondaries in cervical lymph nodes  diagnosis...
Lymph node metastasis in neck (secondaries in cervical lymph nodes diagnosis...
 
Pleomorphic adenoma
Pleomorphic adenomaPleomorphic adenoma
Pleomorphic adenoma
 
Thyroidectomy
Thyroidectomy Thyroidectomy
Thyroidectomy
 
Solitary Thyroid Nodule
Solitary Thyroid NoduleSolitary Thyroid Nodule
Solitary Thyroid Nodule
 
Local and regional flaps in head and neck reconstruction
Local and regional flaps in head and neck reconstructionLocal and regional flaps in head and neck reconstruction
Local and regional flaps in head and neck reconstruction
 
Thyroglossal duct cysts
Thyroglossal duct cystsThyroglossal duct cysts
Thyroglossal duct cysts
 
Weber ferguson incison (poster)
Weber ferguson incison (poster)Weber ferguson incison (poster)
Weber ferguson incison (poster)
 
Thyroidectomy- operative surgery
Thyroidectomy- operative surgeryThyroidectomy- operative surgery
Thyroidectomy- operative surgery
 
Salivary gland tumors
Salivary gland tumors Salivary gland tumors
Salivary gland tumors
 
Cystic hygroma
Cystic hygromaCystic hygroma
Cystic hygroma
 
Neck swelling
Neck swellingNeck swelling
Neck swelling
 
Radical neck dissection
Radical neck dissectionRadical neck dissection
Radical neck dissection
 
Thyroglossalcyst
ThyroglossalcystThyroglossalcyst
Thyroglossalcyst
 

Similar to Parotidectomy

CP ANGLE TUMORS MANAGEMENT
CP ANGLE TUMORS MANAGEMENT CP ANGLE TUMORS MANAGEMENT
CP ANGLE TUMORS MANAGEMENT Vamsi Reloaded
 
SALIVARY GLANDS, ANATOMY, DISEASE AND MANAGEMENT
SALIVARY GLANDS, ANATOMY, DISEASE AND MANAGEMENTSALIVARY GLANDS, ANATOMY, DISEASE AND MANAGEMENT
SALIVARY GLANDS, ANATOMY, DISEASE AND MANAGEMENTEdouardMudekereza
 
Phonosurgery and speech therapy
Phonosurgery and speech therapyPhonosurgery and speech therapy
Phonosurgery and speech therapyUtpal Sarmah
 
DISORDERS OF SALIVARY GLANDS.pptx
DISORDERS OF SALIVARY GLANDS.pptxDISORDERS OF SALIVARY GLANDS.pptx
DISORDERS OF SALIVARY GLANDS.pptxDeepshikhaKar1
 
Topic review spinal cord tumor new
Topic review  spinal cord tumor newTopic review  spinal cord tumor new
Topic review spinal cord tumor newTeerapong
 
CARCINOMA MAXILLARY SINUS MANAGEMENT RADIATION ONCOLOGY
CARCINOMA MAXILLARY SINUS MANAGEMENT RADIATION ONCOLOGYCARCINOMA MAXILLARY SINUS MANAGEMENT RADIATION ONCOLOGY
CARCINOMA MAXILLARY SINUS MANAGEMENT RADIATION ONCOLOGYPaul George
 
Metastasis of Neck Node with Unknown Primary
Metastasis of Neck Node with Unknown Primary Metastasis of Neck Node with Unknown Primary
Metastasis of Neck Node with Unknown Primary Himanshu Soni
 
Acs0205 Oral Cavity Procedures
Acs0205 Oral Cavity ProceduresAcs0205 Oral Cavity Procedures
Acs0205 Oral Cavity Proceduresmedbookonline
 
Acs0206 Parotidectomy
Acs0206 ParotidectomyAcs0206 Parotidectomy
Acs0206 Parotidectomymedbookonline
 
Ca external and middle ear staging to management1
Ca external and middle ear staging to management1Ca external and middle ear staging to management1
Ca external and middle ear staging to management1Dr Durgesh Kumar
 
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA Surgical approaches & newer treatment o...
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA  Surgical approaches & newer treatment o...JUVENILE NASOPHARYNGEAL ANGIOFIBROMA  Surgical approaches & newer treatment o...
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA Surgical approaches & newer treatment o...Utkal Mishra
 
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA Surgical approaches & Newer treatment o...
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA  Surgical approaches & Newer treatment o...JUVENILE NASOPHARYNGEAL ANGIOFIBROMA  Surgical approaches & Newer treatment o...
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA Surgical approaches & Newer treatment o...Dr Utkal Mishra
 
Anesthesia consideration for parotidectomy
Anesthesia  consideration for parotidectomyAnesthesia  consideration for parotidectomy
Anesthesia consideration for parotidectomyTayyab_khanoo9
 
The frontal sinus(osteoma, inverted papilloma, fibrous dysplasia)
The frontal sinus(osteoma, inverted papilloma, fibrous dysplasia)The frontal sinus(osteoma, inverted papilloma, fibrous dysplasia)
The frontal sinus(osteoma, inverted papilloma, fibrous dysplasia)Shekhar Krishna Debnath
 

Similar to Parotidectomy (20)

Parotidectomy
ParotidectomyParotidectomy
Parotidectomy
 
CP ANGLE TUMORS MANAGEMENT
CP ANGLE TUMORS MANAGEMENT CP ANGLE TUMORS MANAGEMENT
CP ANGLE TUMORS MANAGEMENT
 
SALIVARY GLANDS, ANATOMY, DISEASE AND MANAGEMENT
SALIVARY GLANDS, ANATOMY, DISEASE AND MANAGEMENTSALIVARY GLANDS, ANATOMY, DISEASE AND MANAGEMENT
SALIVARY GLANDS, ANATOMY, DISEASE AND MANAGEMENT
 
Phonosurgery and speech therapy
Phonosurgery and speech therapyPhonosurgery and speech therapy
Phonosurgery and speech therapy
 
Parotid gland tumours Conference Presentation
Parotid gland tumours Conference PresentationParotid gland tumours Conference Presentation
Parotid gland tumours Conference Presentation
 
DISORDERS OF SALIVARY GLANDS.pptx
DISORDERS OF SALIVARY GLANDS.pptxDISORDERS OF SALIVARY GLANDS.pptx
DISORDERS OF SALIVARY GLANDS.pptx
 
Topic review spinal cord tumor new
Topic review  spinal cord tumor newTopic review  spinal cord tumor new
Topic review spinal cord tumor new
 
Angiofibroma
AngiofibromaAngiofibroma
Angiofibroma
 
CARCINOMA MAXILLARY SINUS MANAGEMENT RADIATION ONCOLOGY
CARCINOMA MAXILLARY SINUS MANAGEMENT RADIATION ONCOLOGYCARCINOMA MAXILLARY SINUS MANAGEMENT RADIATION ONCOLOGY
CARCINOMA MAXILLARY SINUS MANAGEMENT RADIATION ONCOLOGY
 
Juvenile angiofibroma (sbo 2)
Juvenile angiofibroma (sbo 2)Juvenile angiofibroma (sbo 2)
Juvenile angiofibroma (sbo 2)
 
Metastasis of Neck Node with Unknown Primary
Metastasis of Neck Node with Unknown Primary Metastasis of Neck Node with Unknown Primary
Metastasis of Neck Node with Unknown Primary
 
Acs0205 Oral Cavity Procedures
Acs0205 Oral Cavity ProceduresAcs0205 Oral Cavity Procedures
Acs0205 Oral Cavity Procedures
 
Acs0206 Parotidectomy
Acs0206 ParotidectomyAcs0206 Parotidectomy
Acs0206 Parotidectomy
 
Ca external and middle ear staging to management1
Ca external and middle ear staging to management1Ca external and middle ear staging to management1
Ca external and middle ear staging to management1
 
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA Surgical approaches & newer treatment o...
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA  Surgical approaches & newer treatment o...JUVENILE NASOPHARYNGEAL ANGIOFIBROMA  Surgical approaches & newer treatment o...
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA Surgical approaches & newer treatment o...
 
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA Surgical approaches & Newer treatment o...
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA  Surgical approaches & Newer treatment o...JUVENILE NASOPHARYNGEAL ANGIOFIBROMA  Surgical approaches & Newer treatment o...
JUVENILE NASOPHARYNGEAL ANGIOFIBROMA Surgical approaches & Newer treatment o...
 
Anesthesia consideration for parotidectomy
Anesthesia  consideration for parotidectomyAnesthesia  consideration for parotidectomy
Anesthesia consideration for parotidectomy
 
The frontal sinus(osteoma, inverted papilloma, fibrous dysplasia)
The frontal sinus(osteoma, inverted papilloma, fibrous dysplasia)The frontal sinus(osteoma, inverted papilloma, fibrous dysplasia)
The frontal sinus(osteoma, inverted papilloma, fibrous dysplasia)
 
Tumours of the parapharyngeal space
Tumours of the parapharyngeal spaceTumours of the parapharyngeal space
Tumours of the parapharyngeal space
 
Surgical management of rhinosinusitis
Surgical management of rhinosinusitisSurgical management of rhinosinusitis
Surgical management of rhinosinusitis
 

Recently uploaded

Call Girls Hyderabad Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Hyderabad Just Call 9907093804 Top Class Call Girl Service AvailableCall Girls Hyderabad Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Hyderabad Just Call 9907093804 Top Class Call Girl Service AvailableDipal Arora
 
VIP Call Girls Noida Sia 9711199171 High Class Call Girl Near Me
VIP Call Girls Noida Sia 9711199171 High Class Call Girl Near MeVIP Call Girls Noida Sia 9711199171 High Class Call Girl Near Me
VIP Call Girls Noida Sia 9711199171 High Class Call Girl Near Memriyagarg453
 
VIP Call Girl Sector 10 Noida Call Me: 9711199171
VIP Call Girl Sector 10 Noida Call Me: 9711199171VIP Call Girl Sector 10 Noida Call Me: 9711199171
VIP Call Girl Sector 10 Noida Call Me: 9711199171Call Girls Service Gurgaon
 
Call Girl In Zirakpur ❤️♀️@ 9988299661 Zirakpur Call Girls Near Me ❤️♀️@ Sexy...
Call Girl In Zirakpur ❤️♀️@ 9988299661 Zirakpur Call Girls Near Me ❤️♀️@ Sexy...Call Girl In Zirakpur ❤️♀️@ 9988299661 Zirakpur Call Girls Near Me ❤️♀️@ Sexy...
Call Girl In Zirakpur ❤️♀️@ 9988299661 Zirakpur Call Girls Near Me ❤️♀️@ Sexy...Sheetaleventcompany
 
Call Girls Thane Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Thane Just Call 9907093804 Top Class Call Girl Service AvailableCall Girls Thane Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Thane Just Call 9907093804 Top Class Call Girl Service AvailableDipal Arora
 
Russian Call Girls in Noida Pallavi 9711199171 High Class Call Girl Near Me
Russian Call Girls in Noida Pallavi 9711199171 High Class Call Girl Near MeRussian Call Girls in Noida Pallavi 9711199171 High Class Call Girl Near Me
Russian Call Girls in Noida Pallavi 9711199171 High Class Call Girl Near Memriyagarg453
 
Call Girl Raipur 📲 9999965857 ヅ10k NiGhT Call Girls In Raipur
Call Girl Raipur 📲 9999965857 ヅ10k NiGhT Call Girls In RaipurCall Girl Raipur 📲 9999965857 ヅ10k NiGhT Call Girls In Raipur
Call Girl Raipur 📲 9999965857 ヅ10k NiGhT Call Girls In Raipurgragmanisha42
 
Jaipur Call Girls 9257276172 Call Girl in Jaipur Rajasthan
Jaipur Call Girls 9257276172 Call Girl in Jaipur RajasthanJaipur Call Girls 9257276172 Call Girl in Jaipur Rajasthan
Jaipur Call Girls 9257276172 Call Girl in Jaipur Rajasthanindiancallgirl4rent
 
Mangalore Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Mangalore Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real MeetMangalore Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Mangalore Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real MeetCall Girls Service
 
Ozhukarai Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Ozhukarai Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real MeetOzhukarai Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Ozhukarai Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real MeetCall Girls Service
 
Ernakulam Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Ernakulam Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real MeetErnakulam Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Ernakulam Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real MeetCall Girls Chandigarh
 
Call Girls Service Anantapur 📲 6297143586 Book Now VIP Call Girls in Anantapur
Call Girls Service Anantapur 📲 6297143586 Book Now VIP Call Girls in AnantapurCall Girls Service Anantapur 📲 6297143586 Book Now VIP Call Girls in Anantapur
Call Girls Service Anantapur 📲 6297143586 Book Now VIP Call Girls in Anantapurgragmanisha42
 
Call Girls Service Faridabad 📲 9999965857 ヅ10k NiGhT Call Girls In Faridabad
Call Girls Service Faridabad 📲 9999965857 ヅ10k NiGhT Call Girls In FaridabadCall Girls Service Faridabad 📲 9999965857 ヅ10k NiGhT Call Girls In Faridabad
Call Girls Service Faridabad 📲 9999965857 ヅ10k NiGhT Call Girls In Faridabadgragmanisha42
 
VIP Call Girl DLF Phase 2 Gurgaon (Noida) Just Meet Me@ 9711199012
VIP Call Girl DLF Phase 2 Gurgaon (Noida) Just Meet Me@ 9711199012VIP Call Girl DLF Phase 2 Gurgaon (Noida) Just Meet Me@ 9711199012
VIP Call Girl DLF Phase 2 Gurgaon (Noida) Just Meet Me@ 9711199012adityaroy0215
 
Call Girl Amritsar ❤️♀️@ 8725944379 Amritsar Call Girls Near Me ❤️♀️@ Sexy Ca...
Call Girl Amritsar ❤️♀️@ 8725944379 Amritsar Call Girls Near Me ❤️♀️@ Sexy Ca...Call Girl Amritsar ❤️♀️@ 8725944379 Amritsar Call Girls Near Me ❤️♀️@ Sexy Ca...
Call Girl Amritsar ❤️♀️@ 8725944379 Amritsar Call Girls Near Me ❤️♀️@ Sexy Ca...Sheetaleventcompany
 
Call Girls Patiala Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Patiala Just Call 9907093804 Top Class Call Girl Service AvailableCall Girls Patiala Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Patiala Just Call 9907093804 Top Class Call Girl Service AvailableDipal Arora
 
❤️♀️@ Jaipur Call Girls ❤️♀️@ Meghna Jaipur Call Girls Number CRTHNR Call G...
❤️♀️@ Jaipur Call Girls ❤️♀️@ Meghna Jaipur Call Girls Number CRTHNR   Call G...❤️♀️@ Jaipur Call Girls ❤️♀️@ Meghna Jaipur Call Girls Number CRTHNR   Call G...
❤️♀️@ Jaipur Call Girls ❤️♀️@ Meghna Jaipur Call Girls Number CRTHNR Call G...Gfnyt.com
 
dhanbad Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
dhanbad Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meetdhanbad Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
dhanbad Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real MeetCall Girls Service
 
❤️♀️@ Jaipur Call Girl Agency ❤️♀️@ Manjeet Russian Call Girls Service in Jai...
❤️♀️@ Jaipur Call Girl Agency ❤️♀️@ Manjeet Russian Call Girls Service in Jai...❤️♀️@ Jaipur Call Girl Agency ❤️♀️@ Manjeet Russian Call Girls Service in Jai...
❤️♀️@ Jaipur Call Girl Agency ❤️♀️@ Manjeet Russian Call Girls Service in Jai...Gfnyt.com
 
Call Girls Chandigarh 👙 7001035870 👙 Genuine WhatsApp Number for Real Meet
Call Girls Chandigarh 👙 7001035870 👙 Genuine WhatsApp Number for Real MeetCall Girls Chandigarh 👙 7001035870 👙 Genuine WhatsApp Number for Real Meet
Call Girls Chandigarh 👙 7001035870 👙 Genuine WhatsApp Number for Real Meetpriyashah722354
 

Recently uploaded (20)

Call Girls Hyderabad Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Hyderabad Just Call 9907093804 Top Class Call Girl Service AvailableCall Girls Hyderabad Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Hyderabad Just Call 9907093804 Top Class Call Girl Service Available
 
VIP Call Girls Noida Sia 9711199171 High Class Call Girl Near Me
VIP Call Girls Noida Sia 9711199171 High Class Call Girl Near MeVIP Call Girls Noida Sia 9711199171 High Class Call Girl Near Me
VIP Call Girls Noida Sia 9711199171 High Class Call Girl Near Me
 
VIP Call Girl Sector 10 Noida Call Me: 9711199171
VIP Call Girl Sector 10 Noida Call Me: 9711199171VIP Call Girl Sector 10 Noida Call Me: 9711199171
VIP Call Girl Sector 10 Noida Call Me: 9711199171
 
Call Girl In Zirakpur ❤️♀️@ 9988299661 Zirakpur Call Girls Near Me ❤️♀️@ Sexy...
Call Girl In Zirakpur ❤️♀️@ 9988299661 Zirakpur Call Girls Near Me ❤️♀️@ Sexy...Call Girl In Zirakpur ❤️♀️@ 9988299661 Zirakpur Call Girls Near Me ❤️♀️@ Sexy...
Call Girl In Zirakpur ❤️♀️@ 9988299661 Zirakpur Call Girls Near Me ❤️♀️@ Sexy...
 
Call Girls Thane Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Thane Just Call 9907093804 Top Class Call Girl Service AvailableCall Girls Thane Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Thane Just Call 9907093804 Top Class Call Girl Service Available
 
Russian Call Girls in Noida Pallavi 9711199171 High Class Call Girl Near Me
Russian Call Girls in Noida Pallavi 9711199171 High Class Call Girl Near MeRussian Call Girls in Noida Pallavi 9711199171 High Class Call Girl Near Me
Russian Call Girls in Noida Pallavi 9711199171 High Class Call Girl Near Me
 
Call Girl Raipur 📲 9999965857 ヅ10k NiGhT Call Girls In Raipur
Call Girl Raipur 📲 9999965857 ヅ10k NiGhT Call Girls In RaipurCall Girl Raipur 📲 9999965857 ヅ10k NiGhT Call Girls In Raipur
Call Girl Raipur 📲 9999965857 ヅ10k NiGhT Call Girls In Raipur
 
Jaipur Call Girls 9257276172 Call Girl in Jaipur Rajasthan
Jaipur Call Girls 9257276172 Call Girl in Jaipur RajasthanJaipur Call Girls 9257276172 Call Girl in Jaipur Rajasthan
Jaipur Call Girls 9257276172 Call Girl in Jaipur Rajasthan
 
Mangalore Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Mangalore Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real MeetMangalore Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Mangalore Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
 
Ozhukarai Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Ozhukarai Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real MeetOzhukarai Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Ozhukarai Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
 
Ernakulam Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Ernakulam Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real MeetErnakulam Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
Ernakulam Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
 
Call Girls Service Anantapur 📲 6297143586 Book Now VIP Call Girls in Anantapur
Call Girls Service Anantapur 📲 6297143586 Book Now VIP Call Girls in AnantapurCall Girls Service Anantapur 📲 6297143586 Book Now VIP Call Girls in Anantapur
Call Girls Service Anantapur 📲 6297143586 Book Now VIP Call Girls in Anantapur
 
Call Girls Service Faridabad 📲 9999965857 ヅ10k NiGhT Call Girls In Faridabad
Call Girls Service Faridabad 📲 9999965857 ヅ10k NiGhT Call Girls In FaridabadCall Girls Service Faridabad 📲 9999965857 ヅ10k NiGhT Call Girls In Faridabad
Call Girls Service Faridabad 📲 9999965857 ヅ10k NiGhT Call Girls In Faridabad
 
VIP Call Girl DLF Phase 2 Gurgaon (Noida) Just Meet Me@ 9711199012
VIP Call Girl DLF Phase 2 Gurgaon (Noida) Just Meet Me@ 9711199012VIP Call Girl DLF Phase 2 Gurgaon (Noida) Just Meet Me@ 9711199012
VIP Call Girl DLF Phase 2 Gurgaon (Noida) Just Meet Me@ 9711199012
 
Call Girl Amritsar ❤️♀️@ 8725944379 Amritsar Call Girls Near Me ❤️♀️@ Sexy Ca...
Call Girl Amritsar ❤️♀️@ 8725944379 Amritsar Call Girls Near Me ❤️♀️@ Sexy Ca...Call Girl Amritsar ❤️♀️@ 8725944379 Amritsar Call Girls Near Me ❤️♀️@ Sexy Ca...
Call Girl Amritsar ❤️♀️@ 8725944379 Amritsar Call Girls Near Me ❤️♀️@ Sexy Ca...
 
Call Girls Patiala Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Patiala Just Call 9907093804 Top Class Call Girl Service AvailableCall Girls Patiala Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Patiala Just Call 9907093804 Top Class Call Girl Service Available
 
❤️♀️@ Jaipur Call Girls ❤️♀️@ Meghna Jaipur Call Girls Number CRTHNR Call G...
❤️♀️@ Jaipur Call Girls ❤️♀️@ Meghna Jaipur Call Girls Number CRTHNR   Call G...❤️♀️@ Jaipur Call Girls ❤️♀️@ Meghna Jaipur Call Girls Number CRTHNR   Call G...
❤️♀️@ Jaipur Call Girls ❤️♀️@ Meghna Jaipur Call Girls Number CRTHNR Call G...
 
dhanbad Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
dhanbad Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meetdhanbad Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
dhanbad Call Girls 👙 6297143586 👙 Genuine WhatsApp Number for Real Meet
 
❤️♀️@ Jaipur Call Girl Agency ❤️♀️@ Manjeet Russian Call Girls Service in Jai...
❤️♀️@ Jaipur Call Girl Agency ❤️♀️@ Manjeet Russian Call Girls Service in Jai...❤️♀️@ Jaipur Call Girl Agency ❤️♀️@ Manjeet Russian Call Girls Service in Jai...
❤️♀️@ Jaipur Call Girl Agency ❤️♀️@ Manjeet Russian Call Girls Service in Jai...
 
Call Girls Chandigarh 👙 7001035870 👙 Genuine WhatsApp Number for Real Meet
Call Girls Chandigarh 👙 7001035870 👙 Genuine WhatsApp Number for Real MeetCall Girls Chandigarh 👙 7001035870 👙 Genuine WhatsApp Number for Real Meet
Call Girls Chandigarh 👙 7001035870 👙 Genuine WhatsApp Number for Real Meet
 

Parotidectomy

  • 1. PAROTIDECTOMY PRESENTER: DR PRASHANTH L MODERATOR: DR R M LALITHA
  • 2. 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
  • 3. 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.
  • 4. 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
  • 5. SURGICAL ANATOMY Parotid gland  The paired parotid glands are the largest of the major salivary glands  weigh, on average, 15–30 g.  Preauricular region
  • 6.  Boundaries  The parotid duct
  • 7.  Parotid gland is divided by the facial nerve into i. a superficial lobe ii. a deep lobe
  • 8.  An accessory parotid gland
  • 9. 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
  • 10.  Facial nerve and branches Structures within the parotid gland
  • 11.  External carotid artery and its branches
  • 13. 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
  • 14. 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
  • 15. 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.
  • 16.  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.
  • 17. 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.
  • 18.  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.
  • 19.  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.
  • 20. 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
  • 21. 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.
  • 22. PREOPERATIVE CONSENT  Scar  Anesthesia in the greater auricular distribution  Facial nerve weakness  Facial contour  Prominence of auricle  Frey’s syndrome (gustatory sweating)
  • 23. PREOPERATIVE CONSENT  Scar  Anesthesia in the greater auricular distribution  Facial nerve weakness  Facial contour  Prominence of auricle  Frey’s syndrome (gustatory sweating)
  • 24. 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.
  • 25. 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.
  • 26. 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
  • 27.  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.
  • 28. TECHNIQUE  A modified Blair incision  An alternative incision is a modified face-lift incision.
  • 29.  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.
  • 30.  The skin incision is made through the subcutaneous tissues and platysma muscle.  Greater auricular nerve.
  • 31.  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
  • 32.  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.
  • 33.  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
  • 34.  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
  • 35.  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.
  • 36.  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.
  • 37.  When necessary, the facial nerve can be identified in the mastoid bone by mastoidectomy and followed peripherally.
  • 38.  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.
  • 39.  The facial nerve is followed peripherally, the desired portion of the gland is dissected from facial nerve branches and the specimen removed.
  • 40.  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.
  • 41.  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.
  • 42.  After the superficial portion of the gland is removed.  The wound is carefully inspected and bleeding sites are controlled with bipolar electrocautery or ligatures
  • 43.  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.
  • 44.  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.
  • 45.  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.
  • 46.  Adjuvant radiation therapy is recommended for select malignancies including i. metastatic cutaneous squamous cell carcinoma ii. high-grade and advanced parotid malignancies
  • 47. 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.
  • 48.  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.
  • 49. 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
  • 50. 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.
  • 51.  SURGICAL TECHNIQUE: 1. Preparation 2. Incisions and flap elevation 3. Deeper dissection 4. Facial nerve mobilisation
  • 52. 5. Removal of superficial gland 6. Deep parotidectomy 7. Total Parotidectomy with Facial Nerve Sacrifice 8. Resection of Adjacent Structures and Reconstruction
  • 53. 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.
  • 54.  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.
  • 55.  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.
  • 56. INCISIONS AND FLAP ELEVATION
  • 57. INCISIONS AND FLAP ELEVATION
  • 58. INCISIONS AND FLAP ELEVATION
  • 59.
  • 60.
  • 62.
  • 63.
  • 65.
  • 66.  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.
  • 67.
  • 68. 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.
  • 69.  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.
  • 70.  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
  • 71.  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.
  • 73.
  • 74.
  • 75.  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.
  • 76.  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.
  • 77. 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.
  • 78.  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
  • 79.  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.
  • 80.  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
  • 81. 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.
  • 82.  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.
  • 83. COMPLICATIONS 1. Hematoma 2. Infection 3. Facial nerve palsy 4. Salivary fistula 5. Gustatory sweating/ Frey’s syndrome 6. Cosmetic deformity
  • 84.  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
  • 85.  Infection is rare  Some tumors presents with obstructive symptoms if infected.  Prophylactic antibiotics are given if operating on an infected gland. INFECTION
  • 86.  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
  • 87.  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.
  • 88.  When palsy is due to partial or total loss of facial nerve: i. reconstruction ii. rehabilitation of face
  • 89.  Presents after suture removal at the suture line and posterior to ear lobule.  Pressure dressing.  Drains  Anticholinergic drugs- to reduce salivary secretion SALIVARY FISTULA
  • 90.
  • 91.  Auriculotemporal syndrome.  60% of all parotidectomy cases.  Discomfort, localized facial sweating and flushing during mastication. FREY’S SYNDROME
  • 92.  Due to parasympathetic and sympathetic secretomotor stimuli misdirected to cholinergic receptors of sweat glands during healing after parotid surgery.
  • 93.  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.
  • 94.  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
  • 95.  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
  • 96.  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
  • 97. 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

Editor's Notes

  1. The paired parotid glands are the largest of the major salivary glands and weigh, on average, 15–30 g. Located in preauricular region and along the posterior surface of the mandible
  2. The parotid gland is bounded superiorly by the zygomatic arch. Inferiorly, the tail of the parotid gland extends down and abuts the anteromedial margin of the sternocleidomastoid muscle. This tail of the parotid gland extends posteriorly over the superior border of the sternocleidomastoid muscle toward the mastoid tip. The deep lobe of the parotid lies within the parapharyngeal space The parotid duct exits the gland anteriorly, crosses the masseter muscle, curves medially around its anterior margin, pierces the buccinator muscle, and enters the mouth opposite the 2nd upper molar tooth.
  3. The superficial lobe, overlying the lateral surface of the masseter. The deep lobe is medial to the facial nerve and located between the mastoid process of the temporal bone and the ramus of the mandible.
  4. An accessory parotid gland may also be present lying anteriorly over the masseter muscle between the parotid duct and zygoma. Its ducts empty directly into the parotid duct through one tributary
  5. SMAS is a fibrous network that invests the facial muscles, and connects them with the dermis. It is continuous with the platysma inferiorly; superiorly it attaches to the zygomatic arch. In the lower face, the facial nerve courses deep to the SMAS and the platysma. The parotid glands are contained within two layers of parotid fascia, which extend from the zygoma above and continue as cervical fascia below.
  6. Enters through posteromedial surface and exits through anteromedial surface of the parotid gland Main trunk divides into the upper temporofacial and lower cervicofacial divisions approximately 1.3 cm from the stylomastoid foramen. The upper temporofacial division forms the frontal, temporal, zygomatic, and buccal branches. The lower cervicofacial division forms the marginal mandibular and cervical branches.
  7. It gives off the transverse facial artery inside the gland before dividing into the internal maxillary and the superficial temporal arteries
  8. The maxillary and superficial temporal veins merge into the retro-mandibular vein within the parotid gland, but are not responsible for draining the gland. Venous drainage of the parotid itself is to tributaries of external and internal jugular veins.
  9. Parotid lymphnodes are embedded in the gland, especially near its superficial surface. Both groups drain to cervical lymphnodes.
  10. Scar: Usually very good healing ex-cept over the mastoid where some scarring may occur Anaesthesia in the greater auricular distribution: Skin of inferior part of auricle, and overlying the angle of the mandible Facial nerve weakness: Temporary weakness common (<50%); permanent weakness rare
  11. Facial contour: loss of parotid tissue leads to a more defined angle of mandible, and deepening of retromandibular sulcus Prominence of auricle: This is probably due to loss of innervation of the postauricular muscles and preauricular scarring Frey’s syndrome (gustatory sweating): Although common, it only very rarely is bad enough to require treatment with Botox injection
  12. A modified Blair incision is planned in a preauricular crease coursing around the ear lobule and then into an upper neck crease Methylene blue can be used to mark points along the proposed incision, which facilitates proper wound alignment and closure.
  13. The ipsilateral face is prepared with an antiseptic solution and the surgical field is draped with a transparent adhesive sterile drape to allow visualization of facial motion. If electrophysiologic facial nerve monitoring is to be used intraoperatively, nerve electrodes are placed in the ipsilateral facial muscles and tested for electrical integrity.
  14. The skin incision is made with a scalpel and carried down through the subcutaneous tissues and platysma muscle. Care is taken to avoid division of the greater auricular nerve.
  15. An anterior flap is elevated superficial to the greater auricular nerve and the parotid fascia (Fig. 14.4). Elevation of a thick flap is desirable to reduce the occurrence of Frey’s syndrome while carefully avoiding violation of any neoplasm at the surface of the gland. As the flap is elevated toward the anterior aspect of the gland, the peripheral branches of the facial nerve are carefully avoided. A posterior, inferior flap is also elevated to expose the tail of the parotid gland. After elevation, the flaps are retracted with silk sutures or selfretaining hooks.
  16. The facial nerve usually courses superficial to this vessel and division of this structure can contribute to increased venous bleeding during dissection of the gland. Occasionally some or all of the branches of the facial nerve will be found deep to the vein.
  17. Care must be taken to avoid pressure or traction injury of the facial nerve during retraction of the gland.
  18. Anatomic distortion by a neoplasm or operative manipulation must be considered.
  19. In cases of previous parotid surgery or recurrent tumor, the usual dissection described above is not always possible.
  20. If any injured facial nerve branches are identified, they are repaired immediately using a microscopic repair technique.
  21. The incision site is marked with a surgical marker. The incision begins in the preauricular crease at the superior root of the helix and curves gently below the lobule, and then turns anteriorly to run horizontally in a skin crease approximately two finger widths below the angle of the mandible
  22. The surgeon may crosshatch the incision lines superficially with a no. 10 or 15 blade to assist in precise realignment during closure. The incision is then made from superior to inferior through the skin into the subcutaneous tissue with the scalpel.
  23. Flap should be raised immediately over the parotid fascia, which is recognizable as a white fibrous layer deep to the subcutaneous fat and superficial musculoaponeurotic system layer. Care should be taken not to enter a superficial tumor or the substance of the gland during flap elevation.
  24. Flap elevation continues with Jones scissors spread open perpendicularly along the parotid fascia; the scissors opens tunnels along the parotid gland which are then connected with blunt and sharp dissection over the parotid fascia
  25. The anterior edge of the sternocleidomastoid muscle is identified, and the greater auricular nerve and external jugular vein, located just anterior to the nerve, are identi-
  26. The parotid gland is next separated from the anterior sternocleidomastoid muscle by sharp dissection. The gland is secured with Kocher clamps along its inferior border away from any tumor and retracted superomedially to assist in dissection. The gland also is separated bluntly from the tragal cartilage by spreading with Jones scissors parallel to the plane of the cartilage down to the level of the tragal cartilaginous pointer.
  27. After the parotid gland has been completely separated from the sternocleidomastoid muscle and the tragus, the posterior belly of the digastric muscle should be identified. The search for this muscle should not be too low in the surgical field, thereby putting the internal jugular vein or accessory nerve at unnecessary risk. too anterior in the field, puts the marginal branch of the facial nerve at risk.
  28. The mastoid tip and the posterior border of the angle of the mandible serve as landmarks for the posterior digastric muscle. Once the muscle belly is identified immediately deep to the angle of the mandible, the remainder of the parotid gland is freed with blunt dissection. At this point, entire inferior surface of the parotid gland, the posterior belly of the digastric muscle, mastoid tip and tragal cartilage is exposed.
  29. The main trunk of the facial nerve exits the stylomastoid foramen immediately posterior to the styloid process. The nerve gives off branches to the posterior belly of the digastric muscle and postauricular muscles before it turns anterolaterally and enters the parotid gland just anterior to the border where the digastric muscle inserts into the mastoid. Tumors may thin the nerve or displace the trunk, but the position where the nerve enters the gland is constant.
  30. Placing a finger on the mastoid tip, the surgeon uses the position of the cartilaginous tragal pointer and superior edge of the digastric muscle to identify the position of the facial nerve. It may be helpful to identify deeper structures such as the styloid process or tympanomastoid suture line to aid in nerve identification.
  31. Further mobilization is performed by separating gland from the nerve, proceeding anteriorly; often the assistant will notice some twitching of the face during this separation The surgeon should dissect distally along the nerve to identify the pes and confirm that the main trunk has been identified proximal to any significant branches.
  32. these veins can be cauterized with bipolar cautery or ligated depending on their size.
  33. The essence of deep parotidectomy is vascular control. Once the surgeon has made the decision to perform deep parotid gland removal, the intraglandular segments of the external carotid artery and deep veins are ligated and divided. The superficial temporal artery and vein are ligated at the superior periphery of the gland.
  34. The posterior facial vein is divided and ligated. The transverse facial artery is divided at the superior anterior periphery of the gland. The only vascular structures remaining at this point are the internal maxillary artery and venous tributaries to the pterygoid musculature located at the posterior border of the masseter muscle and mandibular ramus.
  35. After control of the intraglandular vessels is obtained, the facial nerve trunk and branches are mobilized off of the underlying tumor. After complete mobilization of the nerve, the gland can be bluntly dissected from the deep bed with retraction and separation of the fascial attachments with a small curved clamp. The gland is separated from the temporomandibular joint, bony ear canal, condyle of the mandible, and styloglossus and stylopharyngeus muscles.
  36. The graft should be harvested with meticulous technique, freshened, and approximated without tension or redundancy with minimal use of well-placed 9-0 nylon sutures. ipsilateral hypoglossal nerve by placement of an interpositional jump graft to preserve facial tone.
  37. Infection is rare if the gland is not chronically infected
  38. placement of an angiocatheter from behind the ear into the pocket of saliva. A scopolamine patch is also placed to decrease salivary gland flow.