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16 Partial Parotidectomy Including Deep Lobe andDumb Bell Tumours
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3. Inammatory disease . Occasionally, sialadenitis will not
settle with conservative measures and excision of the
gland becomes an option. These cases can be very challenging due to brosis and sepsis.
4. Malignant tumours. For small, low-grade supercial
tumours, a partial parotidectomy with a margin of at least
1.5 cm may sufce, but otherwise, a total conservative
parotidectomy is advocated.
Recently, there has been a proposal to use a categorization
of parotid tumours considering its size and its position inside
the gland [4]. They divided benign tumours of the parotid
gland into four categories:
Category I includes tumours up to 3cm, which are mobile
and close to outer surface and the parotid borders.
Category II comprises deeper tumours up to 3cm.
Category III includes tumours greater than 3cm involving 2
levels of the parotid gland, and Category IV comprises
tumours greater than 3 cm that involve more than 2
levels.
161
The main indication for supercial partial parotidectomy
is category I and in selected cases of category II.The main
indication for deep partial parotidectomy is benign tumours
limited to the levels III and/or IV with or without extension
to parapharyngeal space.
16.4 Surgical Technique withTips
16.4.1 Preparation andIncision
The anaesthetised patient should be placed supine in the
reverse Trendelenburg (head-up) position with a sandbag
under the contralateral shoulder and the head turned. It is
recommended that the skin be inltrated with 1in 100,000
adrenaline prior to draping, which will aid haemostasis. A
facial nerve monitor should be used with the nerve electrodes
placed in the ipsilateral facial muscles (Fig.16.2). The skin
drapes should be placed so that ipsilateral face can be seen in
its entirety. Cotton wool carefully placed in the external ear
canal is useful to help avoid blood trickling in and causing a
blockage post-operatively.
A Lazy S incision can be performed in a preauricular
crease coursing around the ear lobule and curving in the
neck. Rhytidectomy incision—also called “face lift incision”—leaves a more aesthetic wound given the superior
part of the incision hides under the sideburn and the inferior
part under the occipital hair. The incision is made with a
scalpel up to the subcutaneous plane (Fig.16.2). Skin elevation can be performed with scissors or scalpel, leaving underneath the supercial muscular aponeurotic system (SMAS),
Fig. 16.2 Facial nerve motorization electrodes are placed in ipsilateral
facial muscles. Usually, 4 electrodes are used to monitor the temporal,
zygomatic, buccal, and marginal branches. The incision can be classic
or a rhytidectomy incision
which represents a continuation of the supercial cervical
fascial into the face enfolding the supercial mimetic muscles [5].
16.4.2 Greater Auricular Nerve (GAN)
andSupercial Muscular Aponeurotic
System (SMAS)
The posterior branch of the GAN (the anterior usually has to
be cut due to its direction towards the parotid region) should
be preserved if possible, to reduce the sensory decit of the
pinna.
Once the posterior branch of the GAN has been dissected
from the sternocleidomastoid muscle until the pinna, a ap
of the SMAS can be designed and later used to reconstruct
the area and reduce the risk of Frey’s syndrome. The SMAS
ap is raised towards the antero-inferior aspect of the gland
leaving underneath the parotid gland (Fig.16.3).
16.4.3 Gland Delineation andFacial Nerve
Identication
The posterior and inferior border of the gland must be separated from the sternocleidomastoid muscle and the external
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N. Roland et al.
auditory canal. First, the anterior border of the sternocleidomastoid muscle is delineated. Dissection then progresses
with identication and exposure of the posterior belly of the
digastric muscle lying deep, below the inferior part of the
parotid gland and anterior to the sternocleidomastoid muscle
(Fig.16.4a and b) The digastric muscle is an important landmark for identication of the facial nerve trunk.
Superiorly the preauricular space is separated by dissect-
ing between the cartilaginous external auditory canal and the
Fig. 16.3 After skin elevation, the Greater Auricular Nerve (GAN) and
the Supercial Muscular Aponeurotic System (SMAS) are exposed.
The posterior branch of the GAN should be preserved. A ap of the
SMAS is then designed and raised towards de anteroinferior aspect of
the gland
parotid gland. Using sharp pointed scissors, it is possible to
operate in a bloodless plane just on the tragal perichondrium.
This plane of dissection exposes the cartilage pointer and the
tympanomastoid suture.
The main landmarks of the facial nerve trunk dissection
are as follows:
• The superior margin of the posterior belly of the digastric
muscle. The nerve will be found supercial to and bisect-
ing the angle of the digastric insertion into the digastric
ridge of the mastoid bone.
• The tympanomastoid suture. The facial nerve lies imme-
diately deep and inferior to this at its point of exit from the
skull. This groove is easy to feel, and this is a reliable
landmark.
• The deepest anterior part of cartilaginous external audi-
tory canal, also called pointer. It will be found lying one
cm inferior and one cm deep to the tragal pointer. The
pointer is mobile, and its position can be distorted, so it
should not be relied upon (Fig.16.4c).
The styloid should not be used as a landmark. Although it
is easy to palpate, it lies deep to the exit of the nerve from the
skull base, so dissection onto the styloid may increase the
risk of facial nerve damage. There are cases with large or soft
tumours immediately overlying the main trunk of the nerve
or in surgery for recurrent disease and it is neither possible
nor wise to try and identify the facial nerve trunk at the skull
base. In these cases, it is better to locate and identify one of
the major branches and dissect it in a retrograde manner
from there. The zygomatic and temporal branches of the
upper trunk cross the zygomatic arch anterior to, and within
1–2cm of, the supercial temporal artery. The mandibular
branch can be found at the angle of the mandible, as it lies
supercial to the facial vessels. In some cases, it may also be
necessary to identify the nerve in the mastoid bone itself and
trace it forwards.
a
Fig. 16.4 (a–c) Facial nerve trunk identication should start with
exposure of the main landmarks. First, the superior margin of the posterior belly of the digastric muscle has to be found to determine the
deepness. Later, the tympanomastoid suture and the deepest anterior
part of cartilaginous external auditory canal are dissected. Gently the
tissues between the cartilage and the parotid gland are separated until
the nerve is found
ab
16 Partial Parotidectomy Including Deep Lobe andDumb Bell Tumours
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163
Once the landmarks are localised, the surgical technique
to nd the facial nerve should be gentle and systematic. A
small mosquito is introduced inside the tissues between the
cartilage and the parotid gland, perpendicularly to the
expected facial nerve direction. Then the mosquito is raised
up and the tissues over it are cut. Vessels will be found overlying the nerve, and they should be identied and divided
after carful cautery with ne bipolar forceps. Fibrous tissue
often overlies the nerve and can cause confusion for the inexperienced surgeon, but gentle teasing of theses bres will
reveal the nerve which when found is obvious. Using optical
magnication with operating Loupes is invaluable for this
stage. Conrmation of the nerve can be made with use of a
facial nerve stimulator and the monitor. The nerve should not
be over-stimulated as this can lead to a neuropraxia and temporary weakness. Patience is pivotal.
Once the trunk is localized, one should proceed slowly,
elevating the tissue off the nerve with a mosquito clamp [5].
The tissue over the mosquito clamp should be divided,
always assessing with visual control of the nerve, until the
bifurcation is visualised. Bipolar electrocautery helps controlling bleeding during this part of the procedure and produces minimal lateral thermal injury. The harmonic scalpel
is an alternative and gives a bloodless eld.
16.4.4 Supercial (Lateral) Partial
Parotidectomy
If a level II (supercial inferior) parotidectomy is required,
the inferior (cervicofacial) division of the facial nerve is
traced inferiorly (Fig.16.5a).
Parotid tissue overlying the nerve is divided (Fig.16.5b).
Dissection of the branches of the inferior division continues
(cervical, marginal and some buccal branches). Usually, the
most lateral and inferior branches are traced rst. The specimen is reected medially and upward, exposing the successive branches of the inferior division. The posterior facial
vein usually runs deep to the nerve branches and can be preserved in many cases. The dissection continues until the
anterior border of the parotid gland and Stensen’s duct cranially are exposed. In this way, all the level I and the branches
of the superior division are not dissected or exposed.
In case of Level I parotidectomy (supercial superior) the
procedure is similar but tracing the superior (temporofacial)
division of the facial nerve and not dissecting the inferior
division.
16.4.5 Deep Partial Parotidectomy
If a deep lobe parotidectomy is indicated, the deep levels
III±IV should be removed. Once the facial trunk and bifurcation are exposed, the branches are traced anteriorly 2cm
more. The supercial lobe is reected anteriorly exposing
the nerve and the deep lobe under it (Fig.16.6a, b). Then, the
main trunk and the cervicofacial division are mobilized and
softly retracted superior-medially. In that moment, the deep
lobe tumour can be resected (level III). Removing the deep
lobe, the external carotid artery is exposed. If the tumour is
more superior (level IV), the temporofacial division has to be
mobilized and retracted inferior-medially in order to better
reach level IV. Once the tumour removed, the supercial
lobe is replaced in its original position.
Fig. 16.5 (a and b) To perform supercial partial parotidectomy, one
of the supercial lobes should be dissected from the facial nerve
branches until the anterior border of the parotid gland is exposed. In the
gure, level II (according to the anatomical classication proposed by a
Quer etal. in 2010 [1]) is removed and inferior branches are visible
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a
b
Fig. 16.6 (a and b) If a deep lobe parotidectomy is indicated, the facial
nerve branches are traced anteriorly 2cm more and the supercial lobe
is reected anteriorly. This way, the deep levels are exposed. Then, the
16.4.6 Dumb Bell Tumours
If the deep tumour extends to the parapharyngeal space
(Fig.16.7), the procedure is similar to the deep partial. Once
the tumour has been identied and the deep lobe released,
facial nerve trunk is retracted and the deep lobe is dissected and
removed. In the deep plane, the external carotid artery is exposed
the parapharyngeal part should be addressed. In order to
improve the access, the stylomandibular ligament has to be
identied and cut. This allows pulling supercially the
mandible and helps in releasing the tumour from the parapharyngeal space by blunt dissection.
16 Partial Parotidectomy Including Deep Lobe andDumb Bell Tumours
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Fig. 16.7 Magnetic resonance imaging that shows a Dumb bell
tumour, affecting the parotid deep lobe and extending towards the parapharyngeal space
16.4.7 Closure
Once the tumour is removed, bleeding points are carefully
controlled with bipolar electrocautery. In cases of partial
deep parotidectomy and dumb bell tumours, the supercial
lobe is repositioned carefully and sutured. Then the SMAS
ap is repositioned and sutured, with the intention to reduce
risk of Frey’s Syndrome. Usually, a drainage tube is placed
under the SMAS ap (Fig.16.8a). Additionally, if the dissection has been extended, a smaller drainage tube can be
placed between the ap and the skin. The subcutaneous
plane is approximated, with an intradermic suture. Tissue
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glue is nding popularity in reducing dead space and
encouraging the ap to remain adherent to the residual tissues. A dressing is performed to smoothly compress the
parotid gland.
16.4.8 Extracapsular Dissection
Mobile lesions in the parotid tail are most suitable for ECD,
or smaller tumours fairly supercial within the supercial
lobe. Inammatory lesions, large tumours, those extending
into the deep lobe, and those where malignancy is suspected
are unsuitable for ECD (Fig.16.8b).
A smaller incision depending on position and size of the
lesion can be used, but otherwise the same incision for a
standard parotidectomy. The tumour is then re-assessed for
suitability for ECD after raising of aps. Use of the facial
nerve monitor is essential.
A cruciate incision is made through the fascia over the
lesion and careful bloodless dissection is made down to the
region of the tumour. A plane is developed between the capsule of the tumour and normal parotid tissue. Traction and
counter-traction from an assistant are pivotal in this technique, and meticulous haemostasis is essential (Fig.16.8c).
Magnication with Loupes is recommended.
The tumour capsule and its fronds/pseudopodia are followed in the extracapsular plane. The tumour will then be
extirpated in toto. The cuff of parotid tissue retracted can
then be reapproximated to close the dead space (Fig.16.8d).
It is claimed with some support in the literature that this
approach has a lower risk of facial palsy, Frey’s syndrome
and is less likely to cause sensory loss. However, if there is
intraoperative doubt about the pathology or position of the
facial nerve, conversion to a partial parotidectomy with
formal nerve identication should be undertaken.
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a
b
c
Fig. 16.8 (a–d) The remaining parotid tissue is replaced. A drainage tube is positioned under the supercial Muscular Aponeurotic System
(SMAS) ap and it is replaced over the gland
16 Partial Parotidectomy Including Deep Lobe andDumb Bell Tumours
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d
167
Fig. 16.8 (continued)
16.5 Postoperative Care
Postoperative care of the patient after partial parotidectomy
includes analgesics and early start of oral intake. The drainage tube is usually removed on the rst 2 days when the
drainage is less than 20cc in 24h. The incision should be
cleaned and disinfected regularly, and after a week, the
sutures can be removed. Postoperative antibiotics are not
used.
Early complications should be kept in mind during post-
operative care [6].
Facial nerve paresis or paralysis can occur as an early
complication due to excessive manipulation and stretching,
inadvertent section, electrocautery burn, or excessive stimulation of the nerve during the procedure. Ocular protection
with articial teardrops and night occlusion of the eye is
mandatory in these cases.
Haemorrhage or haematoma can also occur with exteriorization of the haematoma or, in some cases, the development
of an asphyxiant hematoma. The treatment consists of emergency surgery under general anaesthesia to evacuate the hae-
matoma and identify any bleeding vessels. If the airway is
compromised, a tracheostomy may be required.
Infection is uncommon but should be suspected if fever
and inammation signs appear on the skin. In this situation,
antibiotics are indicated. Skin-ap necrosis can also occur,
usually in the distal part of the postauricular skin ap. The
treatment consists of conservative debridement of necrotic
tissue and local wound care.
Salivary stula or collection (sialocoele) tends to occur
within a few days of the surgery. A collection can be quite
tense and painful, especially when eating. Collections can
be aspirated in clinic, and this may need to be repeated on
several occasions. A leak will need appropriate dressing and
maintenance of wound hygiene. Antibiotics should be considered to prevent or treat secondary infection that can
occur. Both leaks and collections almost always settle, but it
can take 1–2weeks. If the stula does not settle conservatively, botulinum toxin injected into the residual gland can
be used [7].
Frey’s syndrome is more common than realised and many
patients have evidence of it if tested with Minor’s starch
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iodine test. It can be treated with subdermal injections of
botulinum toxin. The risk of Frey’s syndrome is decreased
by more partial parotidectomy and the restoration of integrity of the supercial muscular aponeurotic system (SMAS)
layer. The use of interpositional aps (e.g. sternomastoid)
can be effective but is not usually used routinely.
Neuroma of the greater auricular nerve presents as a very
localized tender nodule just anterior to the superior part of
the sternomastoid muscle, usually a year or so after parotidectomy. It can be managed by simple local excision and
burying of the fresh nerve end in the muscle. Preservation of
the posterior branch and diathermy of the cut end of the
nerve at the end of parotidectomy are manoeuvres used to
help avoid this problem.
Recurrent salivary gland tumours pose a difcult problem. The risk of malignant degeneration is increased, and
treatment should be offered. The recurrence is often multifocal. Cross-sectional imaging is mandatory to plan surgery and the patient will be at high risk of facial nerve
damage.
Occasionally, the denitive histopathology may be
unexpectedly malignant. Each case has to be assessed on its
own merits and should be discussed by a Multidisciplinary
Meeting. If there has been a reasonable surgical margin in
a low-grade tumour, then no further intervention may be
required. However, postoperative radiotherapy or further
surgery to the primary or a neck dissection may be
indicated.
References
1. Quer M, Pujol A, León X, López M, García J, Orús C, Sañudo JR.
Parotidectomías en tumores benignos: clasicación Sant Pau de la
extensión de la resección. Acta Otorrinolaringológica Espanola.
2010;61(1):1–5. https://doi.org/10.1016/j.otorri.2009.10.003.
2. Quer M, Marchal F, Vander Poorten V, Chevalier D, León X,
Eisele D, Dulguerov P. Classication of parotidectomies: a
proposal of the European Salivary Gland Society. Eur Arch
Otorhinolaryngol. 2016;273(10):3307–12. https://doi.org/10.1007/
s00405- 016- 3916- 6.
3. Mikaszewski B, Markiet K, Smugała A, Stodulski D, Szurowska
E, Stankiewicz C. Diffusion- and perfusion-weighted magnetic
resonance imaging—an alternative to ne needle biopsy or only an
adjunct test in preoperative differential diagnostics of malignant and
benign parotid tumors? J Oral Maxillofac Surg. 2017;75(10):2248–
53. https://doi.org/10.1016/j.joms.2017.03.018.
4. Quer M, Vander Poorten V, Takes RP, Silver CE, Boedeker C, De
Bree R.Surgical options in benign parotid tumors: a proposal for
classication. Eur Arch Otorhinolaryngol. 2017;274(11):3825–36.
https://doi.org/10.1007/s00405- 017- 4650- 4.
5. Mirapeix RM, Quer M, García J, León X, López M, Sañudo
JR.Hands-on training course on surgical anatomy of the neck, larynx and parotid gland. 2019.
6. Myers EN, Ferris RL. Salivary gland disorders. 2007. https://doi.
org/10.1007/978- 3- 540- 47072- 4.
7. Pantel M, Volk G, Guntinas-Lichius O, Wittekindt C.Botulinum
toxin type b for the treatment of a sialocele after parotidectomy.
Head Neck. 2013;35:1–2. https://doi.org/10.1002/HED.
Total Conservative andRadical
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Parotidectomy
VincentVanderPoorten andMichaelElliott
17
17.1 Introduction
The parotid gland, the main salivary gland in the head and
neck, is situated in the preauricular area and lls the space
between the temporal bone and the posterior aspect of the
mandible. It is divided into supercial and deep lobes by the
path of the facial nerve through the parotid gland. The bulk
of the gland is found in the supercial lobe (i.e., lateral to the
facial nerve), and it is in this location that most tumours in
the parotid gland are found.
Parotid gland surgery with the aim of identifying and preserving the facial nerve has a fairly short history [1, 2]. In the
1950s, surgeons developed a standardized approach, identi-
fying the facial nerve (CN VII) trunk at the stylomastoid
foramen and then proceeding distally from the facial nerve
trunk, following and preserving the peripheral branches
whilst dissecting the supercial parotid tissue off the nerve
(Fig.17.1).
Before this surgical revolution in the 1950s, surgeons
generally performed parotid tumour enucleation, out of a
fear of damaging CN VII [3, 4]. Needless to say, this approach
was associated with a high rate of tumour recurrence and a
high rate of facial nerve damage.
This chapter deals with the extent of various surgical
approaches to remove the entire parotid gland without (or
with) additional nonparotid tissues.
V. VanderPoorten (*)
Department of Oncology, section Head and Neck Oncology;
Otorhinolaryngology–Head and Neck Surgery, University
Hospitals Leuven, KU Leuven,
Leuven, Belgium
e-mail: Vincent.vanderpoorten@uzleuven.be
M. Elliott
Department of Otolaryngology, Head and Neck Surgery, Chris
O’Brien Lifehouse, Sydney, NSW, Australia
e-mail: Michael.elliott@lh.org.au
© Springer Nature Switzerland AG 2024
R. Simo et al. (eds.), Atlas of Head and Neck Surgery, Springer Surgery Atlas Series,
https://doi.org/10.1007/978-3-031-36593-5_17
169
170
to s
Auriculotemporal
in
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Cut cartilage of
external acoustic
meatus
Posterior
auricular nerve
Facial nerve
branch to posterior
digastric muscle
Cut edge of
Sternocleidomastoid
muscle
Accessory CN Xl
Facial nerve branch
tylohyoid muscle
Greater
auricular nerve
V. VanderPoorten and M. Elliott
nerve
Superficial
temporal artery
Capsule of
temporomandibular
joint
Transverse
facial artery
Deep lobe
Parotid duct
Masseter
muscle
Facial artery
Parotid gland
Retromandibular ve
External jugular
vein
Fig. 17.1 The parotid gland and facial nerve. Following identication
of the facial nerve at its exit point from the stylomastoid foramen, the
parotid tissue located supercially to it (supercial lobe) is removed.
This comprises about 80% of parotid tissue. After this “supercial
17.2 Indications forParotid Surgery
Parotid surgery is mainly performed for oncological reasons
(both benign and malignant tumours) and is much less commonly performed for inammatory and/or obstructive disease.
The aim of tumour surgery is to completely excise the tumour
with an adequate margin [5]. The extent of this resection is
usually tailored to the local extension and specic growth pattern of the tumour [6]. The European Salivary Gland Society
(ESGS) recently published a useful classication to uniformly
describe the extent of any parotid surgical procedure performed [7]. This classication sums up the resected parotid
levels, as well as the nonparotid structures that were resected.
Following this classication, this chapter deals with ESGS I–
IV parotidectomy with or without resection of additional
structures, listed on Table17.1 and shown on Fig.17.2.
parotidectomy,” about 20% of parotid tissue remains under the plane of
the nerve. Removing this tissue whilst preserving the facial nerve completes a “total conservative parotidectomy”
17.2.1 Indications foraPartial Parotidectomy
Most benign tumours can be removed with a partial parotidectomy sparing the facial nerve. The aim of this approach is
to remove the tumour with a cuff of normal parotid tissue for
a surgical margin. Often the tumour will abut one or more
branches of the facial nerve, and the limit of resection is the
tissue abutting the nerve. The benets of this approach are
limiting dissection of parotid tissue and identifying only
those branches of the facial nerve that are required to safely
excise the tumour. This approach has the advantages of
reducing facial nerve exposure and potential injury to
branches not intimately associated with the tumour, reducing
the incidence of Frey’s syndrome, and reducing the cosmetic
defect associated with more radical parotid surgical
procedures.
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