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Lymph Node Excision Biopsy
https://t.me/med1917
VictoriaHarries andAshleyHay
8.1 Introduction
The head and neck region includes over 200 lymph nodes
[1]. Lymph nodes are a major constituent part of the lymphatic system and are formed from multiple types of lymphoid cells [2]. The lymphatic system functions to drain the
lymphatic uid in a one-way network of lymphatic vessels
[3] and allows the lymphatic cells to perform a vital and
complex immunological function [4]. Enlargement of one or
more lymph nodes is a common presentation that can indicate a vast number of benign or malignant conditions.
A cervical lymph node biopsy may be needed in some
instances to establish or conrm a diagnosis. In other situations, however, an open cervical biopsy is not recommended
and can be harmful. Therefore, a thorough understanding of
the differential diagnosis and appropriate investigational
strategy is essential before performing a surgical or open
lymph node biopsy.
A differential diagnosis is formed by assessing a full history and examination with appropriate workup, as indicated
by patient’s age, risk factors, and physical ndings. A broad
differential diagnosis includes reactive lymphadenopathy
from bacterial or viral causes, head and neck malignancies,
haematological malignancies, and metastatic deposits from
other primaries outside of the head and neck.
An open cervical biopsy in patients with metastatic squamous cell carcinoma or a diagnosis of tuberculosis (TB) in
the lymph node can lead to suboptimal outcomes. An open
biopsy of squamous cell carcinoma can lead to disease in the
cutaneous tissues, and biopsy of a TB lymph node can lead
to a chronic draining stula (Fig.8.1).
V. Harries
Department of Otolaryngology, University Hospitals Bristol NHS
Foundation Trust, Bristol, UK
A. Hay (*)
Department of Otolaryngology, University of Edinburgh, NHS
Lothian’s University Hospitals Division, Edinburgh, Scotland
e-mail: ashley.hay@nhs.net
8
Fig. 8.1 Cervical tuberculosis discharging through a neck wound
(scrofula)
Recent advances in ultrasound technology have made it
possible to assess the structure of cervical lymph nodes in
detail, enabling accurate diagnosis of even small lesions and
targeted sampling with ne-needle aspiration (FNA) or core
biopsies. Ultrasound and FNA are safe and inexpensive
investigations that reliably detect suspicious and malignant
cervical adenopathy, without risk of seeding the cutaneous
tissues. In the workup of any cervical lymphadenopathy, an
ultrasound and FNA cytology is a pivotal investigation [5].
In some instances, however, an open biopsy is required. In
the diagnosis of lymphoma, the architecture of the node is
often required for an accurate diagnosis. In nodes with
unequivocal or insufcient FNA cytology results, open
biopsy might be needed for diagnosis, and if non-squamous
malignant cells are found on cytology, further tissue may be
required to aid the search for a primary tumour by providing
more tissue to be interrogated with immunohistochemical
tests.
© 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_8
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V. Harries and A. Hay
Knowledge of the anatomy of the neck and cranial nerves
is fundamental to performing an open cervical biopsy. The
surgical approach and technique varies according to the location of the lymph node and the nerves potentially at risk. For
a diagnostic procedure, the risks of any negative sequelae
should be minimized. The nature of a lymph node biopsy is
often presumed to be straightforward, but this procedure can
be underestimated and may become difcult, involving small
incisions and lymph nodes that are often bigger, deeper, and
closer to major vessels or nerves than initially appreciated.
8.2 Preoperative Checklist
andConsiderations
8.2.1 History andExamination
A comprehensive ENT history and examination are essential
to ensure that the necessary investigations have been considered and to identify patients who require an excisional
biopsy. A detailed history of the neck swelling should be
taken to ascertain the duration, location, and any change in
size.
Associated symptoms and constitutional symptoms
should also be elicited in the history. Associated symptoms
related to the head and neck, such as dysphagia, hoarseness,
odynophagia, unilateral sore throat, and otalgia, are all signicant and require a detailed investigation of the upper
aerodigestive tract.
Constitutional symptoms such as fatigue, weight loss, and
tiredness may indicate a disseminated disease process. Type
B symptoms such as night sweats, pruritis, and loss of
appetite can indicate lymphoma. The patient’s smoking status and alcohol history should also be recorded, in addition
to any previous head and neck malignancies or radiation. A
recent travel history and social contacts with any unwell
family members or friends is also important, to identify
potential infective causes.
A physical examination should include palpation of the
neck to conrm the location, consistency, and mobility of the
enlarged lymph node. A hard, xed lymph node is suggestive
of carcinoma, whereas a mobile, rubbery node is typical of
lymphoma. A detailed examination includes inspection and
palpation of the oral cavity and a exible nasoendoscopy
(FNE) examination of the postnasal space, tongue base,
hypopharynx, and larynx, to assess for a cause in the upper
aerodigestive tract.
The location of the lymph node can suggest the potential
site of primary pathology, because the lymphatic system has
predictable drainage pathways. An enlarged lymph node in
the supraclavicular fossa should be evaluated with a high
index of suspicion and can often indicate intra-abdominal
malignancy [6].
8.2.2 Investigations
Appropriate investigations depend on the ndings from the
history and examination. The rst-line investigation for a
suspicious neck mass in most cases is ultrasound and FNA
(Fig.8.2). Further imaging that is tailored to the differential
diagnosis can include chest radiography, CT scans, MRI, or
positron emission tomography (PET).
An ultrasound scan assesses the nodal architecture, hilar
shape, and internal vascularity, to identify malignant lymph
nodes. Reactive lymph nodes usually appear enlarged but have
a well-dened and retained reniform shape and echogenic
hilum. Rounded nodes, nodes with central necrosis and loss of
hilar architecture, and nodes increasing in size are all features
indicating malignancy [7, 8]. Additional features can be specic
to a diagnosis, such as intranodal microcalcication, which is
suggestive of a metastatic papillary thyroid lymph node [9].
If malignancy is not high in the differential diagnosis,
blood tests should be considered to identify an infective
cause. Examples include a peripheral blood smear, full blood
count (FBC), erythrocyte sedimentation rate (ESR), lactate
dehydrogenase (LDH), Mantoux skin test, and serology testing for toxoplasmosis, cytomegalovirus (CMV), EpsteinBarr virus (EBV), Brucella, and Bartonella.
Fig. 8.2 Ultrasound-guided ne-needle aspiration (FNA) of a lymph
node
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8.2.3 Anatomy andAnatomical
Considerations
The lymphatic system of the head and neck can be divided
into the supercial and deep network by the deep cervical
fascia. The supercial lymphatics drain the skin of the head
and neck into the suboccipital, preauricular, postauricular,
and external jugular lymph nodes, and, ultimately, into the
deep jugular lymph nodes. The deep lymphatics drain the
mucous membranes of the upper aerodigestive tract, thyroid,
and larynx directly into the deep cervical lymph node chains.
The neck can be divided into the anterior and posterior
triangles, bounded by the layers of the deep cervical fascia
(Fig. 8.3). The boundaries of the anterior triangle are the
inferior border of the mandibular ramus superiorly, the anterior border of the sternocleidomastoid muscle laterally, and
the midline. The posterior triangle is bounded by the posterior border of the sternocleidomastoid medially, the clavicle
inferiorly, and the anterior border of the trapezius laterally.
The posterior triangle contains the cutaneous branches of the
cervical plexus, spinal accessory nerve, and the transverse
cervical and suprascapular vessels.
The American Academy of Otolaryngology and Head and
Neck Surgery (AAO-HNS) and the American Joint
Committee on Cancer (AJCC) have developed a widely
accepted classication of cervical lymph node levels [10, 11]
(Fig. 8.4), after the description of neck drainage from
Memorial Sloan Kettering Cancer Center [12].
8.2.4 Structures at Risk During Lymph Node
Biopsy
8.2.4.1 Accessory Nerve
The accessory nerve is a pure motor nerve that supplies the
sternocleidomastoid (SCM) and trapezius muscles. The spinal and cranial roots of the accessory nerve exit the cranium
through the jugular foramen. As the nerve exits the skull base
and enters the neck, it lies between the internal carotid artery
and internal jugular vein. It descends obliquely, usually running supercial to the internal jugular vein but in rare cases
running dorsal to it. The nerve travels along the levator scapulae before reaching the upper part of the SCM.It descends
obliquely to reach the upper part of the SCM and passes deep
to or through the SCM to enter the posterior triangle. It can
therefore be injured in the anterior triangle and in the posterior triangle during a lymph node biopsy.
In the anterior triangle, the transverse process of C1 can
be a useful landmark, as it is palpable in most people. The
internal jugular vein is found anterior to it. Careful dissection
of this area exposes the posterior belly of the digastric muscle and then allows safe identication of the internal jugular
vein and accessory nerve. In addition, deep to the posterior
border of the posterior belly of the digastric muscle lies the
hypoglossal nerve.
Erb’s point, at the junction between the upper third and
lower two thirds on the posterior border of the SCM muscle,
marks the point where the branches of the cervical plexus
Fig. 8.3 The different anatomical triangles in the neck
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Fig. 8.4 The American Joint Committee on
Cancer (AJCC) classication of cervical lymph
node levels
V. Harries and A. Hay
II
I
B
I
A
B
II
A
exit. The accessory nerve exits the SCM to enter the posterior triangle about 1cm behind Erb’s point.
In the posterior triangle, the nerve is supercial; it can be
found just beneath the subcutaneous fat and is at risk of
injury in this location. The accessory nerve ultimately
reaches the anterior border of the trapezius muscle, entering
the muscle on the undersurface. The nerve is at high risk of
injury in the posterior triangle, because it is supercial, it is
small, and there are no xed anatomical points. Lymph nodes
that are frequently the focus for biopsy run in a chain around
the nerve and often are in contact with it.
8.2.4.2 Marginal Mandibular Nerve
The marginal mandibular nerve is a branch of the facial
nerve, which provides motor innervation to the lower lip and
chin. The nerve exits the inferior portion of the parotid gland
and courses deep to the supercial layer of the cervical fascia. It runs across the mandible close to the the bony notch
made by the facial artery. It then ascends to the corner of the
mouth more anteriorly [13]. It is supercial to the facial
artery and vein, and to the submandibular gland. It can be
injured when raising the skin ap or if the skin incision is too
close to the mandible.
The marginal mandibular branch runs within 1.5cm of
the inferior border of the mandible, but can be found along or
above the border of the mandible. Common practice to avoid
injury to the nerve is for a skin incision to be at least two
VI
III
IV
V
A
V
B
ngerbreadths below the mandible. Injury to this nerve
results in an asymmetric smile due to loss of the angularis
depressor muscle and impaired lower lip movement
inferiorly.
8.2.4.3 Hypoglossal Nerve
It is rare for the hypoglossal nerve to be injured during a
lymph node biopsy. It exits the skull base through the hypoglossal canal posteriorly in the skull. It then travels inferiorly
adjacent to the vagus nerve and spinal division of the accessory nerve in the carotid sheath. It then passes behind the
vagus nerve and passes between the internal carotid artery
and internal jugular vein. It travels in a deep plane, beneath
the posterior belly of the digastric muscle. The gentle curve
in the nerve is created by the occipital artery looping over the
nerve. It then enters the tongue at the junction of the anterior
two thirds and posterior third of the tongue, between the
hypoglossus muscle deep and the stylohyoid muscle and lingual nerve supercially. It then supplies the motor innervation to the extrinsic and intrinsic muscles of the tongue.
8.2.4.4 Thoracic Duct andAccessory
ThoracicDuct
The thoracic duct on the left and the accessory thoracic duct
on the right are at risk of injury if a lymph node to be sampled is in Level IV or in the supraclavicular fossa. The thoracic duct is located deep behind the lymph nodes in this
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region, but it can become dilated in high-volume disease,
which can increase the risk of injury. It drains into the venous
circulation at the conuence of the internal jugular vein and
subclavian vein. Its passage is highly variable, with a looping
course superior before returning inferior to empty into the
internal jugular vein. It can be found in a triangle between
the phrenic nerve, internal jugular vein, and subclavian vein.
8.2.4.5 Major Cervical Vessels
Lymph nodes can be closely apposed to the major vessels,
particular the internal jugular vein. The carotid and its major
branches have a thick vascular wall and are usually resistant
to invasion. The internal jugular vein is more commonly
invaded or affected by brosis from pathological processes
in adjacent lymph nodes. It also has a thin wall and is at risk
during surgery.
8.2.4.6 Phrenic Nerves
These are found on the prevertebral muscles. They are usually protected by the prevertebral fascia overlying the cervical rootlets. They are identied as the only nerves to have a
lateral-to-medial direction.
8.3 Indications
A number of situations are indications for excisional lymph
node biopsy:
identication and location of the suspicious node, but this
technique is infrequently needed. Close study of preoperative imaging, such as a CT scan, also can be very helpful.
8.4.1 Anaesthetic Considerations
An excisional lymph node biopsy can be performed under
general or local anaesthetic. Local anaesthetic allows for a
shorter recovery period and avoids any individual risks associated with general anaesthetic. The procedure can be easily
underestimated, however, as all major structures in the neck
are in close proximity, and small incisions for a biopsy can
be inadequate to fully expose the anatomy. The threshold for
general anaesthetic should therefore be low, especially for
deep jugular chain lymph nodes. A general anaesthetic also
allows for nerve monitoring if an incisional parotid biopsy is
being performed.
8.4.2 Patient Positioning andDraping
Position the patient supine with a shoulder roll for neck
extension and the head on a doughnut or ring to support the
occiput (Fig.8.5). Putting the operating table with the head
up at approximately 30–45° helps reduce bleeding, improves
access, and can help ventilation (Fig.8.6). The neck can be
draped using a head drape, or the area can be squared draped.
• Non-diagnostic FNA and/or core biopsy results
• Suspected lymphoma (for architecture information or
diagnosis of low-grade lymphomas)
• Persistent paediatric cervical lymphadenopathy with suspicious features on imaging
• HIV cervical lymphadenopathy of unknown cause
• Non-squamous malignancy in which further tissue is
required for immunohistochemistry
8.4 Surgical Technique
The consent process involves a thorough explanation to the
patient of the need for the procedure and the likely effect if it
is not performed. The risks of the procedure should be
explained, with the explanation tailored to the patient and the
operation, taking reasonable care to ensure that the patient is
aware of all material risks [14].
The lymph node identied on ultrasound and subsequent
FNA should be targeted for evaluation, because if the FNA
suggested a malignant process, sampling adjacent nodes may
show only reactive changes. Lymph nodes that are small can
be identied preoperatively with ultrasound guidance to aid
8.4.3 Skin Incision
Determine the direction of Langer’s lines and mark a transverse skin crease incision. Use an existing skin crease where
possible, to improve the cosmesis of the scar (Fig.8.7). Take
into consideration whether the patient may need to undergo
a subsequent neck dissection.
Fig. 8.5 Position of a shoulder roll and head ring
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Fig. 8.6 Position of the bed, with bed broken in centre to allow head
up 30–45° and extension of the atlanto-occipital joint
Fig. 8.8 To expose the lymph
node, the sternocleidomastoid
muscle (SCM) is identied
after subplatysmal aps are
raised
V. Harries and A. Hay
Fig. 8.7 Skin crease incision used for Level II cervical lymph node
biopsy
subcutaneous
tissues
Platysma
muscles
Strap muscles
8.4.4 Elevation ofFlaps
Raise small subplatysmal aps and divide the cervical fascia
overlying the node. Careful dissection is required in the posterior triangle and at Level II in the anterior triangle to minimize the risk to the accessory and marginal mandibular
nerves, given their supercial locations.
Cervical
nodal mass
beneath deep
cervical fascia
Sternocleidomastoi
muscle
8.4.5 Exposing theLymph Node
Identifying the lymph node depends on its position and the
related structures. In most circumstances, the identication of the
sternocleidomastoid muscle allows for lymph node identication (Fig. 8.8). Once the capsule of the lymph node has been
identied, the plane above the capsule should be dissected in all
Digastric
d
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Fig. 8.9 Fully mobilized
lymph node at point of
excision
97
muscle
Strap muscles
Carotid artery
Vagus nerve
Internal jugular vein
Cervical nodal mass
Sternocleidomastoi
muscle
directions, gradually increasing the mobility of the node. A small
area of fascia can be left attached to the node so that it does not
need to be directly handled, which can cause the nodal capsule to
tear. A mixture of sharp and blunt dissection can be used, with
careful bipolar or monopolar cautery for haemostasis. The aim is
to completely excise an intact lymph node (Fig.8.9).
8.4.6 Haemostasis
Ligate or cauterize any visualized vessels. A Valsalva
manoeuvre can be used to check for haemostasis at the end
of the procedure. Drain insertion is not routinely required but
should be considered. Haemostatic agents such as Surgicel
can be used, especially if there is general low-pressure ooze
from divided lymphoid tissue.
8.4.7 Skin Closure
The platysmal layer is closed with interrupted 3-0 Vicryl
sutures. A continuous subcuticular absorbable suture to skin
with 4-0 Monocryl sutures can be used to create a satisfactory cosmetic outcome.
8.4.8 Specimen
Special consideration for the specimen should be taken in
close liaison with the pathology and microbiology depart-
ment. Specimens for microbiology examination need to be
fresh and sterile. Potential TB cultures should be examined
with specic stains, especially Ziehl–Neelsen (ZN) stain. In
lymphoma, the specimen may be required fresh so that ow
cytometry can be performed. For standard histological
examination, the xing agent preferred by the laboratory
should be used.
8.4.9 Specic Lymph Node Biopsy
Techniques
8.4.9.1 Parotid Biopsy
A mass in the parotid gland usually should be removed
with a formal superficial parotidectomy, in which the
facial nerve branches are identified so that they are protected from injury. Parotidectomy may be needed for
diagnostic purposes in cases of equivocal cytology or if a
low-grade lymphoma is considered. However, the parotid
gland has abundant lymphoid tissue, and patients can
present with large, rapidly growing masses (Fig.8.10). In
these situations, a formal parotidectomy or lymph node
biopsy is not possible. The potential for a high-grade
lymphoma needs to be ruled out and a biopsy is required.
In these instances, an incisional biopsy may be
performed.
To minimize injury, an incision should be marked out parallel to any nerve branches. Very slow and judicious dissection should be used to expose the lesion. A facial nerve
monitor may be benecial in these circumstances.
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V. Harries and A. Hay
Fig. 8.10 Patient with large and rapidly growing parotid mass
8.4.9.2 Jugular Digastric Nodes
The lymph node position in the anterior triangle can be either
anterior to the SCM or deep and adjacent to the carotid
sheath and jugular vein. For anterior nodes or large nodes,
exposure of the anterior border of the SCM with lateral
retraction will allow access for node removal. The SCM can
be retracted well with a Langenbeck retractor or Richardson
retractor to optimize access (Fig. 8.11). For deeper nodes,
the access required to allow for retraction of the SCM may
require a large incision, but another option is a musclesplitting approach. This works in large-volume disease that
has splayed the muscle and makes retraction through a
biopsy incision difcult. The muscle can be split in line with
its bres. To avoid injury, care must be taken to understand
the position of the accessory nerve. The use of a self- retaining
retractor (Fig.8.12) can be helpful for this approach.
8.4.9.3 Posterior Triangle Nodes
The lymph nodes in the posterior triangle are either part of
the chain running with the accessory nerve in the superior
aspect of the triangle or they are in the supraclavicular area.
The spinal accessory nerve is very supercial in the posterior
triangle, often just deep to skin, because there is no platysma
muscle in this area.
Supraclavicular nodes often can be large and xed below
the clavicle, with close involvement of the lymphatic vessels
and thoracic duct. These nodes often are sampled with an
incisional biopsy.
Fig. 8.11 Sternocleidomastoid muscle retracted laterally to give
access to Level II lymph node
Fig. 8.12 A self-retaining retractor
8.5 Postoperative Care
8.5.1 Complications
Damage to the marginal mandibular branch of the facial
nerve leads to reduced motor function of the ipsilateral side
of the lower lip, which can be associated with an asymmetric
smile.
Injury to the accessory nerve leads to shoulder pain
and weakness. These symptoms can be reduced with
physiotherapy.
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Damage to vessels can cause intraoperative and postoperative bleeding. If excessive bleeding has occurred or if
there has been extensive dissection, there should be a low
threshold for drain insertion at the end of the procedure and
inpatient admission.
Other nonspecic complications can include formation of
hypertrophic/keloid scars, numbness, and wound dehiscence
or infection.
8.5.2 Follow-Up
Patients should be sent home with wound care and suture
advice, analgesia, and a follow-up appointment for a review
of the histology results. Appropriate onward referral depending on the pathology or microbiology ndings should then be
made.
References
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2. Alex JC.The head and neck lymphatic system. Facial Plast Surg
Clin North Am. 2003;11:43–7.
3. Rouvière H, Valette G.Physiologie du système lymphatique. Paris:
Masson; 1937.
4. Willard-Mack CL. Normal structure, function, and histology of
lymph nodes. Toxicol Pathol. 2006;34:409–24.
5. McQueen AS, Bhatia KS. Head and neck ultrasound: technical
advances, novel applications and the role of elastography. Clin
Radiol. 2018;73:81–93.
6. Baumgart DC, Fischer A. Virchow’s node. Lancet.
2007;370(9598):1568.
7. Papakonstantinou O, Bakantaki A, Paspalaki P, Charoulakis N,
Gourtsoyiannis N. High-resolution and color Doppler ultrasonography of cervical lymphadenopathy in children. Acta Radiol.
2001;42:470–6.
8. Ying M, Bhatia KS, Lee YP, Yuen HY, Ahuja AT.Review of ultrasonography of malignant neck nodes: greyscale, Doppler, contrast
enhancement and elastography. Cancer Imaging. 2014;13:658–69.
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J. Ultrasonographic thyroid ndings suspicious for malignancy.
Diagn Cytopathol. 2013;41:1107–14.
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A, etal. Neck dissection classication update: revisions proposed by
the American Head and Neck Society and the American Academy
of Otolaryngology-Head and Neck Surgery. Arch Otolaryngol
Head Neck Surg. 2002;128:751–8.
11. Robbins KT, Medina JE, Wolfe GT, Levine PA, Sessions RB, Pruet
CW. Standardizing neck dissection terminology. Ofcial report
of the Academy’s Committee for Head and Neck Surgery and
Oncology. Arch Otolaryngol Head Neck Surg. 1991;117:601–5.
12. Spiro RH, Strong EW, Shah JP.Classication of neck dissection:
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2015;350:h2217.
Thyroglossal Duct Cyst
Foramen cecum
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KarticRajaram, JoelSmith, andOmarHilmi
9.1 Introduction
The thyroid gland appears in the embryo as a midline structure on approximately the 24th day of gestation; it projects
downwards from the oor of the pharynx at the point that
corresponds to the foramen cecum in adults [1]. It descends
early in foetal life towards its position in the lower neck, with
the isthmus lying over the second and third tracheal rings.
This tract, known as the thyroglossal duct, maintains its
attachment to the base of the tongue. At the time of its
descent, the hyoid bone is not yet formed. The hyoid bone
divides this tract into upper and lower segments (Fig.9.1).
Hence, the track of descent could be passing in front of,
through, or behind the eventual position of the hyoid body
[2]. During the second embryologic month, the thyroid gland
assumes its nal position anterior to the trachea, at which
time the tract is resorbed.
Thyroglossal duct cysts represent a persistence of this
tract and may be found anywhere in or adjacent to the midline from the tongue base to the thyroid isthmus. Rotation of
the hyoid bone during its development causes the thyroglossal duct to be drawn posteriorly and cranially at the inferior
margin of the bone (see Fig.9.1). Fusion of the second branchial arch in the midline may result in entrapment of the thyroglossal duct by the hyoid bone.
Failure of the resorption process or the presence of
retained epithelial nests along the tract forms the basis for
9
Hyoid bone
Thyroglossal
duct cyst
Pyramidal lobe
thyroid
Fig. 9.1 Sagittal view of a thyroglossal cyst, showing the relationship
between the tract and the thyroid
K. Rajaram
Department of Maxillofacial and Reconstructive Surgery,
Manchester University NHS Foundation Trust, Manchester, UK
J. Smith
Department of ENT, Head, Neck and Thyroid Surgery, Royal
Devon and Exeter Foundation Trust, Nufeld Health, Exeter
Hospital, Exeter, UK
O. Hilmi (*)
Department of Otolaryngology, Glasgow Royal Inrmary,
Glasgow, UK
e-mail: omar.hilmi@ggc.scot.nhs.uk
© 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_9
the development of a thyroglossal duct cyst. These cysts are
found (in order of frequency [3]) beneath the hyoid bone,
above the hyoid bone, or at the level of the hyoid bone.
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